MedWorm.com provides a medical RSS filtering service. Over 6000 RSS medical sources are combined and output via different filters. This feed contains the latest items from the 'Biometals' source. Mon, 06 Feb 2012 13:31:34 +0100 http://www.medworm.com/index.php?rid=5654089&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22297381%26dopt%3DAbstract Authors: Olivares M, Pizarro F, Ruz M, López de Romaña D Abstract Iron (Fe) and zinc (Zn) deficiencies constitute two of the most important nutritional and public health problems affecting developing countries. Combined supplementation or fortification with Zn and Fe are strategies that can be used to improve the Zn and Fe status of a population. However, there is concern about potential negative interactions between these two micronutrients due to a competitive binding to DMT1 and Zip14 transporter. Studies performed in humans have shown an inhibitory effect of Zn on Fe absorption when both minerals are given together as a solution in fasting conditions. We found that at low doses of iron (0.5 mg) the threshold for the inhibition of iron bioavailability was at a Zn:Fe wt/wt rat... Biometals journals http://www.medworm.com/rss/comments.php?id=5654089 Thu, 02 Feb 2012 05:00:00 +0100 5654089 http://www.medworm.com/index.php?rid=5654091&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22294463%26dopt%3DAbstract Authors: Bartnikas TB Abstract Transferrin is an abundant serum metal-binding protein best known for its role in iron delivery. The human disease congenital atransferrinemia and animal models of this disease highlight the essential role of transferrin in erythropoiesis and iron metabolism. Patients and mice deficient in transferrin exhibit anemia and a paradoxical iron overload attributed to deficiency in hepcidin, a peptide hormone synthesized largely by the liver that inhibits dietary iron absorption and macrophage iron efflux. Studies of inherited human disease and model organisms indicate that transferrin is an essential regulator of hepcidin expression. In this paper, we review current literature on transferrin deficiency and present our recent findings, including potential ov... Biometals journals http://www.medworm.com/rss/comments.php?id=5654091 Wed, 01 Feb 2012 05:00:00 +0100 5654091 http://www.medworm.com/index.php?rid=5654090&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22294464%26dopt%3DAbstract Authors: Prohaska JR, Broderius M Abstract Interactions between copper and iron homeostasis have been known since the nineteenth century when anemia in humans was first described due to copper limitation. However, the mechanism remains unknown. Intestinal and liver iron concentrations are usually higher following copper deficiency (CuD). This may be due to impaired function of the multicopper oxidases hephaestin or ceruloplasmin (Cp), respectively. However, iron retention could be due to altered ferroportin (Fpn), the essential iron efflux transporter in enterocytes and macrophages. Fpn mRNA is controlled partially by intracellular iron and IRE dependence. CuD should augment Fpn based on iron level. Some argue that Fpn stability is controlled partially by membrane ferroxidase (GPI-... Biometals journals http://www.medworm.com/rss/comments.php?id=5654090 Wed, 01 Feb 2012 05:00:00 +0100 5654090 http://www.medworm.com/index.php?rid=5594775&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22234495%26dopt%3DAbstract Authors: Li JL, Li HX, Li S, Gao XJ, Xu SW, Tang ZX Abstract Selenium (Se) and Selenoprotein W (SelW) plays a pivotal role in the brain development, function, and degeneration and that SelW expression in the brain may be affected by Se. However, the mechanism which Se regulates the SelW gene expression in neurons remains to be unclear. To investigate the effects of the SelW gene expression and mRNA stability induced by Se, primary cultured chicken embryos neurons derived from 8-day-old chick embryo cerebral hemispheres were treated with 10(-9)-10(-5) mol/l Se as selenite for 3, 6, 12, 24 or 48 h, respectively. The morphology and viability of Neurons was detected. The SelW mRNA expression level and mRNA half-life was examined in Se-treated neurons. The relative low concentrations ... Biometals journals http://www.medworm.com/rss/comments.php?id=5594775 Thu, 12 Jan 2012 05:00:00 +0100 5594775 http://www.medworm.com/index.php?rid=5594774&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22234496%26dopt%3DAbstract Authors: Valdivia-González M, Pérez-Donoso JM, Vásquez CC Abstract To unveil the metabolic impact of tellurite in the bacterial cell, the effect of this toxicant on the expression and activity of key enzymes of the Escherichia coli glycolytic pathway was analyzed. E. coli exposure to tellurite results in: (i) increased glucose consumption, which was paralleled by an increased expression of the glucose transporter-encoding gene ptsG, (ii) augmented phosphoglucoisomerase activity and pgi transcription, (iii) decreased activity of the enzymatic regulators phosphofructokinase and pyruvate kinase. In spite of these observations, increased intracellular pyruvate, phosphoenol pyruvate and phosphorylated sugars was observed. E. coli lacking key glycolytic enzymes was considerably more s... Biometals journals http://www.medworm.com/rss/comments.php?id=5594774 Thu, 12 Jan 2012 05:00:00 +0100 5594774 http://www.medworm.com/index.php?rid=5594772&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22237941%26dopt%3DAbstract Authors: Artini M, Scoarughi GL, Cellini A, Papa R, Barbato G, Selan L Abstract Staphylococcus aureus and Staphylococcus epidermidis are the major cause of infections associated with implanted medical devices. Colonization on abiotic and biotic surfaces is often sustained by biofilm forming strains. Human natural defenses can interfere with this virulence factor. We investigated the effect of human apo-transferrin (apo-Tf, the iron-free form of transferrin, Tf) and holo-transferrin (holo-Tf, the iron-saturated form) on biofilm formation by CA-MRSA S. aureus USA300 type (ST8-IV) and S. epidermidis (a clinical isolate and ATCC 35984 strain). Furthermore S. aureus adhesion and invasion assays were performed in a eukaryotic cell line. A strong reduction in biofilm formation with both T... Biometals journals http://www.medworm.com/rss/comments.php?id=5594772 Thu, 12 Jan 2012 05:00:00 +0100 5594772 http://www.medworm.com/index.php?rid=5594773&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22234497%26dopt%3DAbstract In this report, we investigated the role of divalent cations in adiponectin assembly. Purified adiponectin 18mers, the largest HMW species, did not collapse to smaller oligomers after treatment with high concentrations of EDTA. However, treatment with EDTA or another chelator DTPA inhibited the oligomerization of 18mers from trimers in vitro. Zn(2+) specifically increased the formation of 18mers when compared with Cu(2+), Mg(2+), and Ca(2+). Distribution of adiponectin oligomers secreted from zinc chelator TPEN-treated rat adipocytes skewed toward increased proportions of hexamers and trimers. While we observed presence of zinc in adiponectin purified from calf serum, the role of zinc in disulfide bonding between oligomers was examined because the process is critical for 18mer assembly. Su... Biometals journals http://www.medworm.com/rss/comments.php?id=5594773 Wed, 11 Jan 2012 05:00:00 +0100 5594773 http://www.medworm.com/index.php?rid=5557716&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22205111%26dopt%3DAbstract This report demonstrates the negative effect of a bivalent metal upon the DNA binding property of CHR, which otherwise binds to DNA in presence of metals like Mg(2+)and Zn(2+). The results also indicate that CHR has a potential for chelation therapy in Cu(2+) accumulation diseases. However cytotoxicity of the antibiotic might restrict the use. PMID: 22205111 [PubMed - as supplied by publisher] (Source: Biometals) Biometals journals http://www.medworm.com/rss/comments.php?id=5557716 Thu, 29 Dec 2011 05:00:00 +0100 5557716 http://www.medworm.com/index.php?rid=5557717&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22203404%26dopt%3DAbstract Authors: Boughammoura A, Expert D, Franza T Abstract During infection, the phytopathogenic enterobacterium Dickeya dadantii has to cope with iron-limiting conditions and the production of reactive oxygen species by plant cells. A tight control of the bacterial intracellular iron content is necessary for full virulence of D. dadantii: previous studies have shown that the ferritin FtnA and the bacterioferrtin Bfr, devoted to iron storage, contribute differentially to the virulence of this species. In this work, we investigated the role of the Dps miniferritin in iron homeostasis in D. dadantii. We constructed a Dps-deficient mutant by reverse genetics. This mutant grew like the wild-type stain under iron starvation and showed no decreased iron content. However, the dps mutant display... Biometals journals http://www.medworm.com/rss/comments.php?id=5557717 Wed, 28 Dec 2011 05:00:00 +0100 5557717 http://www.medworm.com/index.php?rid=5544092&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22187125%26dopt%3DAbstract In this study, we probe the solution chemistry of protochelin and its complexes with environmentally relevant trace metals to better understand its effect on metal uptake and cycling. Protochelin exhibits low solubility below pH 7.5 and degrades gradually in solution. Electrochemical measurements of protochelin and metal-protochelin complexes reveal a ligand half-wave potential of 200 mV. The Fe(III)Proto(3-) complex exhibits a salicylate shift in coordination mode at circumneutral to acidic pH. Coordination of Mn(II) by protochelin above pH 8.0 promotes gradual air oxidation of the metal center to Mn(III), which accelerates at higher pH values. The Mn(III)Proto(3-) complex was found to have a stability constant of log β(110) = 41.6. Structural parameters derived from spectroscopic mea... Biometals journals http://www.medworm.com/rss/comments.php?id=5544092 Wed, 21 Dec 2011 05:00:00 +0100 5544092 http://www.medworm.com/index.php?rid=5524579&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22127376%26dopt%3DAbstract Authors: Ge R, Sun X Abstract Helicobacter pylori infections are closely associated with peptic ulcers, gastric malignancy and iron deficiency anemia. Iron is essential for almost all living organisms and the investigation of iron uptake and trafficking system is thus important to understand the pathological roles of H. pylori. Up to now, the iron trafficking system of H. pylori is not yet fully clear and merits further efforts in this regards. The available information about iron uptake and regulation has been discussed in this concise review, such as FeoB in ferrous transportation, FrpB2 in hemoglobin uptake, HugZ in heme processing, virulence factors (VacA and CagA) in transferrin utilization, Pfr and NapA in iron storage and Fur in iron regulation. The identified iron trafficki... Biometals journals http://www.medworm.com/rss/comments.php?id=5524579 Wed, 30 Nov 2011 05:00:00 +0100 5524579 http://www.medworm.com/index.php?rid=5524580&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22124795%26dopt%3DAbstract Authors: Araya M, Andrews M, Pizarro F, Arredondo M Abstract Assessment of proteins in blood and other tissues has failed to identify markers of early copper effects on health. Studies in animal models show that chaperone of SOD (CCS) respond to changes of copper status. Evidence about other copper chaperones (COXIV, ATOX) is not clear. The aim of this study was to assess by means of an in vitro challenge the mRNA relative abundance of ccs, sod1, coxIV, mtIIa and atox in peripheral mononuclear cells (PMNCs) obtained from healthy individuals, acutely and chronically supplemented with small-to-moderate amounts of copper. Healthy participants received 8 mg Cu/d (supplemented group, SG) or placebo, (placebo group, PG) for 2 months. Biochemical indicators were assessed at basal (T0) a... Biometals journals http://www.medworm.com/rss/comments.php?id=5524580 Tue, 29 Nov 2011 05:00:00 +0100 5524580 http://www.medworm.com/index.php?rid=5524581&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22113231%26dopt%3DAbstract Authors: Weaver BP, Andrews GK Abstract Translation of the basolateral zinc transporter ZIP5 is repressed during zinc deficiency but Zip5 mRNA remains associated with polysomes and can be rapidly translated when zinc is repleted. Herein, we examined the mechanisms regulating translation of Zip5. The 3'-untranslated region (UTR) of Zip5 mRNA is well conserved among mammals and is predicted by mFOLD to form a very stable stem-loop structure. Three algorithms predict this structure to be flanked by repeated seed sites for miR-328 and miR-193a. RNAse footprinting supports the notion that a stable stem-loop structure exists in this 3'-UTR and electrophoretic mobility shift assays detect polysomal protein(s) binding specifically to the stem-loop structure in the Zip5 3'-UTR. miR-328 and ... Biometals journals http://www.medworm.com/rss/comments.php?id=5524581 Thu, 24 Nov 2011 05:00:00 +0100 5524581 http://www.medworm.com/index.php?rid=5435916&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22089858%26dopt%3DAbstract Authors: Gorbunov NV, Atkins JL, Gurusamy N, Pitt BR Abstract Although iron is known to be a component of the pathogenesis and/or maintenance of acute lung injury (ALI) in experimental animals and human subjects, the majority of these studies have focused on disturbances in iron homeostasis in the airways resulting from exposure to noxious gases and particles. Considerably less is known about the effect of increased plasma levels of redox-reactive non-transferrin bound iron (NTBI) and its impact on pulmonary endothelium. Plasma levels of NTBI can increase under various pathophysiological conditions, including those associated with ALI, and multiple mechanisms are in place to affect the [Fe(2+)]/[Fe(3+)] redox steady state. It is well accepted, however, that intracellular transport ... Biometals journals http://www.medworm.com/rss/comments.php?id=5435916 Thu, 17 Nov 2011 05:00:00 +0100 5435916 http://www.medworm.com/index.php?rid=5435915&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22089859%26dopt%3DAbstract Authors: Mermod M, Magnani D, Solioz M, Stoyanov JV Abstract The pathway of copper entry into Escherichia coli is still unknown. In an attempt to shed light on this process, a lux-based biosensor was utilized to monitor intracellular copper levels in situ. From a transposon-mutagenized library, strains were selected in which copper entry into cells was reduced, apparent as clones with reduced luminescence when grown in the presence of copper (low-glowers). One low-glower had a transposon insertion in the comR gene, which encodes a TetR-like transcriptional regulator. The mutant strain could be complemented by the comR gene on a plasmid, restoring luminescence to wild-type levels. ComR did not regulate its own expression, but was required for copper-induction of the neighboring, div... Biometals journals http://www.medworm.com/rss/comments.php?id=5435915 Thu, 17 Nov 2011 05:00:00 +0100 5435915 http://www.medworm.com/index.php?rid=5410626&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22083130%26dopt%3DAbstract This study demonstrates that the Alzheimer's tau fragment R2, corresponding to the second repeat of the microtubule-binding domain, can bind to Zn(II), Cd(II) and Hg(II). Isothermal titration calorimetry experiments suggest that the most likely coordination site is the thiol group of Cys291, and this is further confirmed by a control experiment using a C291A mutant peptide. Circular dichroism spectrum reveals that the coordination of group IIB cations, especially Hg(II), can induce pronounced conformational conversions in natively unfolded R2, from random coil to other ordered structures. ThS fluorescence assays and electron microscopy indicate that the group IIB cations promote heparin-induced aggregation of R2, giving relatively small R2 filaments. The efficiency in promoting aggregation... Biometals journals http://www.medworm.com/rss/comments.php?id=5410626 Tue, 15 Nov 2011 05:00:00 +0100 5410626 http://www.medworm.com/index.php?rid=5410628&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22080200%26dopt%3DAbstract Authors: Lupescu A, Jilani K, Zelenak C, Zbidah M, Qadri SM, Lang F Abstract Hexavalent (VI) chromium is a global contaminant with cytotoxic activity. Chromium (VI) induces oxidative stress, inflammation, cell proliferation, malignant transformation and may trigger carcinogenesis and at the same time apoptosis. The toxic effects of chromium (VI) at least partially result from mitochondrial injury and DNA damage. Erythrocytes lack mitochondria and nuclei but may experience an apoptosis-like suicidal cell death, i.e. eryptosis, which is characterized by cell shrinkage and cell membrane scrambling with phosphatidylserine exposure at the cell surface. Eryptosis may result from increase of cytosolic Ca(2+) activity, ATP depletion and/or ceramide formation. The present study explored, wh... Biometals journals http://www.medworm.com/rss/comments.php?id=5410628 Sun, 13 Nov 2011 05:00:00 +0100 5410628 http://www.medworm.com/index.php?rid=5410627&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22080201%26dopt%3DAbstract Authors: Chu YL, Sauble EN, Cabrera A, Roth A, Leigh Ackland M, Mercer JF, Linder MC Abstract Copper transport and accumulation were studied in virgin and lactating C57BL/6 mice, with and without expression of ceruloplasmin (Cp), to assess the importance of Cp to these processes. One hour after i.p. injection of tracer (64)Cu, liver and kidney accounted for 80% of the radioactivity, and mammary gland 1%, while in lactating Cp+/+ mice 2-4 days post partum, uptake by mammary gland was 9-fold higher and that of liver and other organs was decreased, with (64)Cu rapidly appearing in milk. Parallel studies in Cp-/- mice (siblings from same colony) gave virtually identical results. However, their milk contained less (64)Cu, and actual copper contents determined by furnace atomic absorpt... Biometals journals http://www.medworm.com/rss/comments.php?id=5410627 Sun, 13 Nov 2011 05:00:00 +0100 5410627 http://www.medworm.com/index.php?rid=5410629&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22080191%26dopt%3DAbstract Authors: Akatsu H, Hori A, Yamamoto T, Yoshida M, Mimuro M, Hashizume Y, Tooyama I, Yezdimer EM Abstract Abnormal distributions of transition metals inside the brain are potential diagnostic markers for several central nervous system diseases, including Alzheimer's disease (AD), Parkinson's disease, dementia with Lewy bodies (DLB), bipolar disorders and depression. To further explore this possibility, the total concentrations of iron, zinc, copper, manganese, aluminum, chromium and cadmium were measured in post-mortem hippocampus and amygdala tissues taken from AD, DLB and Control patients. A statistically significant near fifty percent reduction in the total copper levels of AD patients was observed in both the hippocampus and amygdala. The statistical power of the hippocampus and... Biometals journals http://www.medworm.com/rss/comments.php?id=5410629 Sat, 12 Nov 2011 05:00:00 +0100 5410629 http://www.medworm.com/index.php?rid=5410630&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22069027%26dopt%3DAbstract Authors: Sadhasivam S, Shanmugam P, Veerapandian M, Subbiah R, Yun K Abstract The fabrication of reliable, green chemistry processes for nanomaterial synthesis is an important aspect of nanotechnology. The biosynthesis of single-pot room-temperature reduction of aqueous chloroaurate ions by Streptomyces hygroscopicus cells has been reported to facilitate the development of an industrially viable greener methodology for the synthesis of technologically important gold nanoparticles (AuNPs). Multidimensional AuNPs are generated via the manipulation of key growth parameters, including solution pH and reaction time. The synthesized nanostructures are characterized by UV/Vis and energy dispersive X-ray analysis studies. Particle morphology is characterized by HRTEM, FE-SEM and BioAFM. Ad... Biometals journals http://www.medworm.com/rss/comments.php?id=5410630 Wed, 09 Nov 2011 05:00:00 +0100 5410630 http://www.medworm.com/index.php?rid=5375841&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22045056%26dopt%3DAbstract Authors: Zhang JL, Li JL, Huang XD, Bo S, Rihua W, Li S, Xu SW Abstract Selenium (Se), selenoprotein N (SelN) and selenoprotein W (SelW) play a crucial role in muscle disorders. Se status highly regulates selenoprotein mRNA levels. However, few attempts have been performed on the effect of dietary Se supplementation on muscle SelN and SelW mRNA levels in birds. To investigate the effects of Se on the regulation of SelN and SelW mRNA levels in muscle tissues, one-day-old male chickens were fed either a commercial diet or a Se-supplemented diet containing 1.0, 2.0, 3.0 or 5.0 mg/kg sodium selenite for 90 days. Muscle tissues (breast, flight, thigh, shank and cardiac muscles) were collected and examined for Se content and mRNA levels of SelN and SelW. Moreover, Selenophosphate synth... Biometals journals http://www.medworm.com/rss/comments.php?id=5375841 Wed, 02 Nov 2011 04:00:00 +0100 5375841 http://www.medworm.com/index.php?rid=5375842&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22038645%26dopt%3DAbstract Authors: Lee J, Postmaster A, Soon HP, Keast D, Carson KC Abstract The actinomycetes are metabolically flexible soil micro-organisms capable of producing a range of compounds of interest, including siderophores. Siderophore production by actinomycetes sampled from two distinct and separate geographical sites in Western Australia were investigated and found to be generally similar in the total percentage of siderophore producers found. The only notable difference was the proportion of isolates producing catechol siderophores with only 3% found in site 1 (from the north-west of Western Australia and reportedly containing 40% magnetite) and 17% in site 2 (a commercial stone fruit orchard in the hills east of Perth with a soil base ranging from sandy loam to laterite). Further detailed... Biometals journals http://www.medworm.com/rss/comments.php?id=5375842 Sat, 29 Oct 2011 04:00:00 +0100 5375842 http://www.medworm.com/index.php?rid=5357909&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22020807%26dopt%3DAbstract In this study, we systematically investigated the mineral composition, crystallinity, and particle size of human H-ferritin (HuHF) reconstituted at four different temperatures (25, 30, 37, and 42°C) by integrated magnetic and transmission electron microscopy analyses. Our results showed that the particle size of reconstituted ferrihydrite cores (~5 nm) in HuHF was temperature-independent. However, the significant changes of the induced magnetization at 5 T field (M(5T)) and remanent magnetization (M(r)) at 5 K clearly showed that the crystallinity of reconstituted cores increased with increasing temperature, indicating that the reaction temperature deeply affects the structural order of reconstituted ferrihydrite cores rather than the particle size, and the reconstituted cores become m... Biometals journals http://www.medworm.com/rss/comments.php?id=5357909 Sat, 22 Oct 2011 04:00:00 +0100 5357909 http://www.medworm.com/index.php?rid=5357910&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22015545%26dopt%3DAbstract We report here the identification of an additional TonB-dependent hemin receptor HvtA, that is needed in conjunction with the HupA protein for optimal hemin utilization. The HvtA protein is significantly homologous to other outer membrane hemin receptors and its expression in trans restored the uptake of hemin and hemoglobin, the latter to a weaker extent, in a mutant strain that was defective in both receptors. Quantitative RT-PCR suggested that transcription of the hvtA gene was iron regulated. The operon containing the hvtA gene is homologous to the operon in V. cholerae containing the hemin receptor gene hutR suggesting a vertical transmission of the hvtA cluster from V. cholerae to V. vulnificus. PMID: 22015545 [PubMed - as supplied by publisher] (Source: Biometals) Biometals journals http://www.medworm.com/rss/comments.php?id=5357910 Fri, 21 Oct 2011 04:00:00 +0100 5357910 http://www.medworm.com/index.php?rid=5357911&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22012445%26dopt%3DAbstract Authors: Hilton RJ, David Andros N, Watt RK Abstract Ferritin iron loading was studied in the presence of physiological serum phosphate concentrations (1 mM), elevated serum concentrations (2-5 mM), and intracellular phosphate concentrations (10 mM). Experiments compared iron loading into homopolymers of H and L ferritin with horse spleen ferritin. Prior to studying the reactions with ferritin, a series of control reactions were performed to study the solution chemistry of Fe(2+) and phosphate. In the absence of ferritin, phosphate catalyzed Fe(2+) oxidation and formed soluble polymeric Fe(III)-phosphate complexes. The Fe(III)-phosphate complexes were characterized by electron microscopy and atomic force microscopy, which revealed spherical nanoparticles with diameters of 10-20�... Biometals journals http://www.medworm.com/rss/comments.php?id=5357911 Thu, 20 Oct 2011 04:00:00 +0100 5357911 http://www.medworm.com/index.php?rid=5357912&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22002344%26dopt%3DAbstract Authors: Keter FK, Darkwa J Abstract Pyrazoles are widely used as core motifs for a large number of compounds for various applications such as catalysis, agro-chemicals, building blocks of other compounds and in medicine. The attractiveness of pyrazole and its derivatives is their versatility that allows for synthesis of a series of analogues with different moieties in them, thus affecting the electronics and by extension the properties of the resultant compounds. In medicine pyrazole is found as a pharmacophore in some of the active biological molecules. While pyrazole derivatives have been extensively studied for many applications including anticancer, antimicrobial, anti-inflammatory, antiglycemic, anti-allergy and antiviral, much less has been reported on their metal counterpar... Biometals journals http://www.medworm.com/rss/comments.php?id=5357912 Sat, 15 Oct 2011 04:00:00 +0100 5357912 http://www.medworm.com/index.php?rid=5323585&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21989767%26dopt%3DAbstract Authors: Chi Z, Wang XX, Ma ZC, Buzdar MA, Chi ZM Abstract The L: -ornithine-N (5)-monooxygenase structural gene (SidA gene, accession number: FJ769160) was isolated from both the genomic DNA and cDNA of the marine yeast Aureobasidium pullulans HN6.2 by inverse PCR and RT-PCR. An open reading frame of 1,461 bp encoding a 486 amino acid protein (isoelectric point: 7.79) with calculated molecular weight of 55.4 kDa was characterized. The promoter of the gene (intronless) was located from -1 to -824 and had three HGATAR boxes which were putative binding motifs for the respective DNA-binding motifs and one CATA box. The SidA gene in A. pullulans HN6.2 was disrupted by integrating the hygromycin B phosphotransferase (HPT) gene into Open Reading Frame of the SidA gene using h... Biometals journals http://www.medworm.com/rss/comments.php?id=5323585 Wed, 12 Oct 2011 04:00:00 +0100 5323585 http://www.medworm.com/index.php?rid=5272541&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21947502%26dopt%3DAbstract Authors: Cambier S, Gonzalez P, Mesmer-Dudons N, Brèthes D, Fujimura M, Bourdineaud JP Abstract The neurotoxic compound methylmercury (MeHg) is a commonly encountered pollutant in the environment, and constitutes a hazard for wildlife and human health through fish consumption. To study the neurotoxic impact of MeHg on piscivorous fish, we contaminated the model fish species Danio rerio for 25 and 50 days with food containing 13.5 μg/g dry weight (dw) of MeHg (0.6 μg MeHg/fish/day), an environmentally relevant dose leading to brain mercury concentrations of 30 ± 4 μg of Hg g(-1) (dw) after 25 days of exposure and 46 ± 7 μg of Hg g(-1) (dw) after 50 days. Brain mitochondrial respiration was not modified by exposure to MeHg, contrary to what happens in skeletal mus... Biometals journals http://www.medworm.com/rss/comments.php?id=5272541 Sun, 25 Sep 2011 04:00:00 +0100 5272541 http://www.medworm.com/index.php?rid=5272542&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21947474%26dopt%3DAbstract Authors: Amin SA, Green DH, Gärdes A, Romano A, Trimble L, Carrano CJ Abstract Iron is an essential element for oceanic microbial life but its low bioavailability limits microorganisms in large areas of the oceans. To acquire this metal many marine bacteria produce organic chelates that bind and transport iron (siderophores). We have previously shown that algal-associated heterotrophic bacteria belonging to the γ-proteobacterial Marinobacter genus release the siderophore vibrioferrin (VF). The iron-VF complex was shown to be both far more photolabile than all previously examined photolabile siderophores and to generate a photoproduct incapable of re-chelating the released iron. Thus, the photo-generated iron was shown to be highly bioavailable both to the producing bacterium and ... Biometals journals http://www.medworm.com/rss/comments.php?id=5272542 Sat, 24 Sep 2011 04:00:00 +0100 5272542 http://www.medworm.com/index.php?rid=5224571&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21915630%26dopt%3DAbstract Authors: Ganguly A, Chakraborty P, Banerjee K, Chatterjee S, Basu S, Sarkar A, Chatterjee M, Choudhuri SK Abstract Multidrug resistance-associated protein 1 (MRP1) reduces intracellular anticancer drug accumulation either by co transporting them with glutathione (GSH) or extruding drug-GSH conjugates outside of the cell. Thus, MRP1 confers multidrug resistance (MDR) and worsen successful chemotherapeutic treatment against cancer. Although the exact mechanism of MRP1 involved in MDR remains unknown, the elevated level of intracellular GSH is considered as a key factor responsible for MDR in cancer. Hence the quest for non-toxic molecules that are able to deplete intracellular GSH has profound importance to subdue MDR. The present preclinical study depicts the resistance reversal pot... Biometals journals http://www.medworm.com/rss/comments.php?id=5224571 Wed, 14 Sep 2011 04:00:00 +0100 5224571 http://www.medworm.com/index.php?rid=5215099&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21901551%26dopt%3DAbstract Authors: Zwang TJ, Gormally MV, Johal MS, Sazinsky MH Abstract Serum proteins exist in a state of higher glycation among individuals with poor glycemic control, notably diabetics. These non-enzymatic modifications via the Maillard reaction have far reaching effects on metabolism and regulation, and may be responsible for increased infection rates within this population. Here we explore the effects of glycation on iron metabolism and innate immunity by investigating the interaction between siderophores and bovine serum albumin (BSA). Using a quartz crystal microbalance with dissipation monitoring to quantify association rates, glycated BSA exhibited a significantly reduced affinity for apo and holo enterobactin compared to a non-glycated BSA standard. Bacterial growth assays in the ... Biometals journals http://www.medworm.com/rss/comments.php?id=5215099 Thu, 08 Sep 2011 04:00:00 +0100 5215099 http://www.medworm.com/index.php?rid=5215100&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21894542%26dopt%3DAbstract Authors: Amin SA, Green DH, Al Waheeb D, Gärdes A, Carrano CJ Abstract Marinobacter belong to the class of Gammaproteobacteria and these motile, halophilic or halotolerent bacteria are widely distributed throughout the world's oceans having been isolated from a wide variety of marine environments. They have also been identified as members of the bacterial flora associated with other marine organisms. Here, using a combination of natural products chemistry and genomic analysis, we assess the nature of the siderophores produced by this genus and their potential relationship to phylogeny and lifestyle/ecological niche of this diverse group of organisms. Our analysis shows a wide level of diversity in siderophore based iron uptake systems among this genus with three general strategies... Biometals journals http://www.medworm.com/rss/comments.php?id=5215100 Tue, 06 Sep 2011 04:00:00 +0100 5215100 http://www.medworm.com/index.php?rid=5185801&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21874527%26dopt%3DAbstract Authors: Slejkovec Z, Falnoga I, van Elteren JT Abstract This work presents an analytical chemist's view on the sometimes unconscious use of arsenic trioxide in (bio)medical research. Arsenic trioxide is a frequently used chemical in cancer treatment research and its action to various malignant cells has been extensively studied and published. Unfortunately some research articles show trivial errors with regards to background knowledge of the chemical, handling the chemical, experimental design and interpretation of results like e.g. in a range of articles comparing advantages of tetraarsenic oxide over arsenic trioxide (dimeric/monomeric) although the dissolution of both yields the same active compound (HAsO(2)). To fully understand the implications of these errors we will highlig... Biometals journals http://www.medworm.com/rss/comments.php?id=5185801 Sat, 27 Aug 2011 23:00:00 +0100 5185801 http://www.medworm.com/index.php?rid=5170451&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21866305%26dopt%3DAbstract Authors: Smidt K, Rungby J Abstract The review collects the emerging information about zinc transporter 3 (ZnT3). ZnT3 has been associated with Alzheimer's disease, airway diseases and diabetes. ZnT3 was discovered and cloned in 1996. Since then, the major interest in the protein has been in its ability to transport zinc into pre-synaptic vesicles of glutamatergic neurones and its role during the development of amyloid β plaques in Alzheimer's disease. Increasing evidence suggests that ZnT3 is present in various cell types like different cell types in the brain, cells from adipose tissue, beta-cells from pancreatic islets, epithelial cells, cells from testis, prostate cancer cells and cells from retina. The expression of ZnT3 is regulated by age, hormones, fatty acids, zinc chelat... Biometals journals http://www.medworm.com/rss/comments.php?id=5170451 Wed, 24 Aug 2011 23:00:00 +0100 5170451 http://www.medworm.com/index.php?rid=5138256&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21842211%26dopt%3DAbstract Authors: Naka H, Crosa JH In this work we demonstrate the existence in Vibrio anguillarum 775 (pJM1) of two chromosomal genes encoding outer membrane proteins that operate in the transport of ferric enterobactin. One of them is a novel receptor that we named FetA and the other is the already characterized FvtA that functions in the uptake of iron complexes of both enterobactin and vanchrobactin. Ferric enterobactin transport proficiency was resumed in double mutants for these two genes when they were complemented with either fetA or fvtA, whereas only the cloned fvtA could complement for ferric vanchrobactin transport. Quantitative RT-PCR assays demonstrated that transcription of the fetA gene is regulated by FetR, that is encoded upstream and in reverse orientation from fetA. This gen... Biometals journals http://www.medworm.com/rss/comments.php?id=5138256 Fri, 12 Aug 2011 23:00:00 +0100 5138256 http://www.medworm.com/index.php?rid=5138257&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21830017%26dopt%3DAbstract Authors: Hödar C, Moreno P, di Genova A, Latorre M, Reyes-Jara A, Maass A, González M, Cambiazo V Acidithiobacillus ferrooxidans is a chemolithoautotrophic acidophilic bacterium that obtains its energy from the oxidation of ferrous iron, elemental sulfur, or reduced sulfur minerals. This capability makes it of great industrial importance due to its applications in biomining. During the industrial processes, A. ferrooxidans survives to stressing circumstances in its environment, such as an extremely acidic pH and high concentration of transition metals. In order to gain insight into the organization of A. ferrooxidans regulatory networks and to provide a framework for further studies in bacterial growth under extreme conditions, we applied a genome-wide annotation procedure to identif... Biometals journals http://www.medworm.com/rss/comments.php?id=5138257 Tue, 09 Aug 2011 23:00:00 +0100 5138257 http://www.medworm.com/index.php?rid=5138258&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21826460%26dopt%3DAbstract Authors: Nam H, Knutson MD The mammalian ZIP (Zrt-, Irt-like Protein) family of transmembrane transport proteins consists of 14 members that share considerable homology. ZIP proteins have been shown to mediate the cellular uptake of the essential trace elements zinc, iron, and manganese. The aim of the present study was to determine the effect of dietary iron deficiency and overload on the expression of all 14 ZIP transporters in the liver, the main site of iron storage. Weanling male rats (n = 6/group) were fed iron-deficient (FeD), iron-adequate (FeA), or iron-overloaded (FeO) diets in two independent feeding studies. In study 1, diets were based on the TestDiet 5755 formulation and contained iron at 9 ppm (FeD), 215 ppm (FeA), and 27,974 ppm (3% FeO). In study 2, diets were bas... Biometals journals http://www.medworm.com/rss/comments.php?id=5138258 Mon, 08 Aug 2011 23:00:00 +0100 5138258 http://www.medworm.com/index.php?rid=5138259&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21822952%26dopt%3DAbstract In this study the chemical stability of As(2)O(3) (As(III)) in cell-free growth media with various compositions was studied (MEM with different amount of amino acids and DMEM). Special attention was given to evaluate the influence of serum (FBS; fetal bovine serum) absence and vitamin C addition on the oxidation of As(III) to As(V) in cell-free growth media. FBS is an important source of antioxidants and vitamin C (ascorbic acid) is acting as a prooxidant in millimolar concentrations. Media were incubated with As(III) (0.6, 2 and 7 μmol l(-1)) up to 72 h. Experiments were performed at 37°C in light or/and in the dark, with or without added serum (10%) or vitamin C (1.4, 0.14 mM). Metabolites were followed with high-performance liquid chromatography directly coupled to a hydride gener... Biometals journals http://www.medworm.com/rss/comments.php?id=5138259 Sat, 06 Aug 2011 23:00:00 +0100 5138259 http://www.medworm.com/index.php?rid=5138260&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21822673%26dopt%3DAbstract Authors: Parrilha GL, Vieira RP, Campos PP, Silva GD, Duarte LP, Andrade SP, Beraldo H Complex [Bi(Lp)(2)]Cl was obtained with 4-hydroxy-3-(3-methylbut-2-enyl)naphthalene-1,2-dione, "lapachol" (HLp). Lapachol, [Bi(Lp)(2)]Cl and BiCl(3) were evaluated in a murine model of inflammatory angiogenesis induced by subcutaneous implantation of polyether polyurethane sponge discs. Intraperitoneal (i.p.) administration of lapachol or [Bi(Lp)(2)]Cl reduced the hemoglobin content in the implants suggesting that reduction of neo-vascularization was caused by lapachol. In the per os treatment only [Bi(Lp)(2)]Cl decreased the hemoglobin content in the implants. Likewise, N-acetylglucosaminidase (NAG) activity decreased in the implants of the groups i.p. treated with lapachol and [Bi(Lp)(2)]Cl while i... Biometals journals http://www.medworm.com/rss/comments.php?id=5138260 Fri, 05 Aug 2011 23:00:00 +0100 5138260 http://www.medworm.com/index.php?rid=5138261&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21818585%26dopt%3DAbstract Authors: Chen Z, Zhou Q, Ge R Helicobacter pylori causes various gastric diseases, such as gastritis, peptic ulcerations and gastric cancer. Triple therapy combining bismuth compounds with two antibiotics is the cornerstone of the treatment of H. pylori infections. Up to now, the molecular mechanisms by which bismuth inhibits the growth of H. pylori are far from clear. In the bacterial tricarboxylic acid (TCA) cycle, fumarase catalyses the reversible hydration of fumarate to malic acid. Our previous proteomic work indicated that fumarase was capable of bismuth-binding. The interactions as well as the inhibitory effects of bismuth to fumarase have been characterized in this study. The titration of bismuth showed that each fumarase monomer binds one mol equiv of Bi(3+), with negligible s... Biometals journals http://www.medworm.com/rss/comments.php?id=5138261 Thu, 04 Aug 2011 23:00:00 +0100 5138261 http://www.medworm.com/index.php?rid=5087598&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21805351%26dopt%3DAbstract In this study, the conditions and mechanism of antibacterial activity of hydrophilic polymer coated silver nanoparticles (AgNPs) against E. coli O157:H7 (CMCC44828) as model pathogen was studied. The AgNPs were coated with amphiphilic polymer that introduced carboxyl groups on the surface to make it water-soluble. The AgNPs were exposed to various treatment conditions of pH and temperature before these were combined with the E. coli. The mechanism of the antibacterial activity was studied through the formation of reactive oxygen species (ROS) that was later suppressed with antioxidant to establish correlation with the AgNPs antimicrobial activity. Studies were carried out at both anaerobic and aerobic conditions. The results indicated that 5 mg/L AgNPs inhibited ~50% of the growth of 10(6... Biometals journals http://www.medworm.com/rss/comments.php?id=5087598 Sat, 30 Jul 2011 23:00:00 +0100 5087598 http://www.medworm.com/index.php?rid=5087599&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21796402%26dopt%3DAbstract Authors: Sarchielli E, Pacini S, Morucci G, Punzi T, Marini M, Vannelli GB, Gulisano M The effects of cadmium on the central nervous system are still relatively poorly understood and its role in neurodegenerative diseases has been debated. In our research, cultured explants from 25 human foetal spinal cords (10-11 weeks gestational age) were incubated with 10 and 100 μM cadmium chloride (CdCl(2)) for 24 h. After treatment, an immunohistochemical study [for Sglial fibrillary acidic protein (GFAP) and choline acetyltransferase (ChAT)], a Western blot analysis (for GFAP, β-Tubulin III, nerve growth factor receptor, Caspase 8 and poly (ADP-ribose) polymerase), and a terminal deoxynucleotidyl transferase biotin-dUTP nick end labelling (TUNEL) assay (for detection of apoptotic bodies) we... Biometals journals http://www.medworm.com/rss/comments.php?id=5087599 Wed, 27 Jul 2011 23:00:00 +0100 5087599 http://www.medworm.com/index.php?rid=5087600&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21779809%26dopt%3DAbstract Authors: López-Rodríguez A, Cárabez-Trejo A, Rosas-Sánchez F, Mejía C, Ruiz-Azuara L, Miledi R, Martínez-Torres A The Casiopeínas(®) are mixed chelate copper (II) complexes and promising antineoplastics agents against cancer cells and tumors in vitro and in vivo. However, the action mode of these compounds is poorly characterized. In this work the effect of the antineoplastic Casiopeína IIIEa on the metabolism and ultrastructure of the yeast Saccharomyces cerevisiae was investigated. Exposure of cells growing in rich or in low-iron medium to 5 μM of the compound decreased duplication time and reduced oxygen consumption. Those cells formed smaller colonies when growing in a non-fermentable carbon source and low-iron medium, and under the light microscope, multiple folds were ... Biometals journals http://www.medworm.com/rss/comments.php?id=5087600 Wed, 20 Jul 2011 23:00:00 +0100 5087600 http://www.medworm.com/index.php?rid=5087602&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21769608%26dopt%3DAbstract Authors: Tonazzi A, Indiveri C The effect of heavy metal cations on the mitochondrial ornithine/citrulline transporter was tested in proteoliposomes reconstituted with the protein purified from rat liver. The transport activity was measured as [(3)H]ornithine uptake in proteoliposomes containing internal ornithine (ornithine/ornithine antiport mode) or as [(3)H]ornithine efflux in the absence of external substrate (ornithine/H(+) transport mode). 0.1 mM Cu(2+), Pb(2+), Hg(2+), Cd(2+) and Zn(2+) strongly inhibited (more than 85%) the antiport; whereas Mn(2+), Co(2+) and Ni(2+) inhibited less efficiently (25, 47 and 69%, respectively). The IC(50) values of the transporter for the different metal ions ranged from 0.71 to 350 μM. Co(2+) and Ni(2+) also inhibited the [(3)H]ornithine effl... Biometals journals http://www.medworm.com/rss/comments.php?id=5087602 Sat, 16 Jul 2011 23:00:00 +0100 5087602 http://www.medworm.com/index.php?rid=5087601&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21769609%26dopt%3DAbstract We report for the first time the affinity constant for the glutathione-iron(II) interaction and use this value to study the cytoplasmic speciation of iron(II). The formation of this complex is a major determinant of the electrode potential of the cytoplasmic ferrous iron pool, a means of selecting between iron(II) and manganese(II) and it provides a substrate for glutaredoxin/iron clusters at the dimer interface of glutaredoxins involved in the synthesis of Fe-S cluster proteins. PMID: 21769609 [PubMed - as supplied by publisher] (Source: Biometals) Biometals journals http://www.medworm.com/rss/comments.php?id=5087601 Sat, 16 Jul 2011 23:00:00 +0100 5087601 http://www.medworm.com/index.php?rid=5038430&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21766174%26dopt%3DAbstract In conclusion, our findings suggest that GSH content and its related enzymes are involved in the Bradyrhizobium sp. tolerance to Cd contributing to the cellular redox balance. PMID: 21766174 [PubMed - as supplied by publisher] (Source: Biometals) Biometals journals http://www.medworm.com/rss/comments.php?id=5038430 Fri, 15 Jul 2011 23:00:00 +0100 5038430 http://www.medworm.com/index.php?rid=5038432&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21755302%26dopt%3DAbstract Authors: Viehweger K, Geipel G, Bernhard G Uranium (U) as a redox-active heavy metal can cause various redox imbalances in plant cells. Measurements of the cellular glutathione/glutathione disulfide (GSH/GSSG) by HPLC after cellular U contact revealed an interference with this essential redox couple. The GSH content remained unaffected by 10 μM U whereas the GSSG level immediately increased. In contrast, higher U concentrations (50 μM) drastically raised both forms. Using the Nernst equation, it was possible to calculate the half-cell reduction potential of 2GSH/GSSG. In case of lower U contents the cellular redox environment shifted towards more oxidizing conditions whereas the opposite effect was obtained by higher U contents. This indicates that U contact causes a consumption of... Biometals journals http://www.medworm.com/rss/comments.php?id=5038432 Wed, 13 Jul 2011 23:00:00 +0100 5038432 http://www.medworm.com/index.php?rid=5038431&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21755303%26dopt%3DAbstract Authors: Di Virgilio AL, Rivadeneira J, Muglia CI, Reigosa MA, Butenko N, Cavaco I, Etcheverry SB The complex of vanadyl(IV) cation with oxodiacetate, VO(oda) caused an inhibitory effect on the proliferation of the human colon adenocarcinoma cell line Caco-2 in the range of 25-100 μM (P < 0.001). This inhibition was partially reversed by scavengers of free radicals. The difference in cell proliferation in the presence and the absence of scavengers was statistically significant in the range of 50-100 μM (P < 0.05). VO(oda) altered lysosomal and mitochondria metabolisms (neutral red and MTT bioassays) in a dose-response manner from 10 μM (P < 0.001). Morphological studies showed important transformations that correlated with the disassembly of actin filaments and a d... Biometals journals http://www.medworm.com/rss/comments.php?id=5038431 Wed, 13 Jul 2011 23:00:00 +0100 5038431 http://www.medworm.com/index.php?rid=5038433&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21732136%26dopt%3DAbstract In this study, we found that the binding of α-casein to bovine spleen ferritin in vitro was blocked by hemin, but not by iron-free hemin (protoporphyrin IX) or zinc-protoporphyrin IX, suggesting that the presence of iron in heme play a key role in this interaction. Indeed, the binding of α-casein to ferritin and biotinylated hemin was inhibited by adding excess ferrous ammonium sulfate (FAS). To further elucidate the binding mechanism of α-casein to biotinylated hemin, Ferrozine and nitrilotriacetic acid (NTA) were used as ferrous and ferric iron chelators, respectively. FAS-mediated inhibition of α-casein to biotinylated hemin was neutralized with Ferrozine, but not NTA, while FAS- as well as ferric chloride-mediated inhibition in their interaction was neutralized by NTA. The followin... Biometals journals http://www.medworm.com/rss/comments.php?id=5038433 Tue, 05 Jul 2011 23:00:00 +0100 5038433 http://www.medworm.com/index.php?rid=5038434&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21717118%26dopt%3DAbstract Authors: Khan HY, Zubair H, Ullah MF, Ahmad A, Hadi SM To account for the observed anticancer properties of plant polyphenols, we have earlier proposed a mechanism which involves the mobilization of endogenous copper ions by polyphenols leading to the generation of reactive oxygen species (ROS) that serve as proximal DNA cleaving agents and lead to cell death. Over the last decade we have proceeded to validate our hypothesis with considerable success. As a further confirmation of our hypothesis, in this paper we first show that oral administration of copper to rats leads to elevated copper levels in lymphocytes. When such lymphocytes with a copper overload were isolated and treated with polyphenols EGCG, genistein and resveratrol, an increased level of DNA breakage was observed. Furthe... Biometals journals http://www.medworm.com/rss/comments.php?id=5038434 Wed, 29 Jun 2011 23:00:00 +0100 5038434 http://www.medworm.com/index.php?rid=5038435&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21706166%26dopt%3DAbstract In this study the transcriptional response of strain CH34 was measured when challenged to sub-lethal concentrations of various essential or toxic metals. Based on the global transcriptional responses for each challenge and the overlap in upregulated genes between different metal responses, the sixteen metals were clustered in three groups. In addition, the transcriptional response of already known metal resistance genes was assessed, and new metal response gene clusters were identified. The majority of the studied metal response loci showed similar expression profiles when cells were exposed to different metals, suggesting complex interplay at transcriptional level between the different metal responses. The pronounced redundancy of these metal resistant regions-as illustrated by the large ... Biometals journals http://www.medworm.com/rss/comments.php?id=5038435 Fri, 24 Jun 2011 23:00:00 +0100 5038435 http://www.medworm.com/index.php?rid=5038437&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21698371%26dopt%3DAbstract Authors: Gradinaru R, Ionas A, Pui A, Zbancioc G, Drochioiu G Sulfur containing biomolecules are involved in complexes with mercury. CoA is an important cofactor for many enzymes involved in metabolic processes. Fatty acyl-CoA-thioesters, substrates of mitochondrial ß-oxidation, are sulfur containing compounds and potential mercury ligands. The CoA-Hg(2+) complex can be easily assessed by UV-Vis spectroscopy or indirectly by antibacterial tests that reconfirmed the protective role of CoA on E. coli. The characteristics of these complexes were determined by means of FTIR spectroscopy. The reverse phase liquid chromatography combined with electrospray ionization tandem mass spectrometry was used for detection of the side-product that resulted through the cleavage of thioesters in the pr... Biometals journals http://www.medworm.com/rss/comments.php?id=5038437 Wed, 22 Jun 2011 23:00:00 +0100 5038437 http://www.medworm.com/index.php?rid=5038436&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21698372%26dopt%3DAbstract Authors: Higuchi M, Yoshikawa Y, Orino K, Watanabe K Diquat toxicity causes iron-mediated oxidative stress; however, it remains unclear how diquat affects iron metabolism. Here, we examined the effect of diquat-induced oxidative stress on iron metabolism in male Fischer-344 rats, with particular focus on gene expression. Hepatic nonheme iron content was unchanged until 20 h after diquat treatment. Hepatic free iron levels increased markedly in the early stages following treatment and remained elevated for at least 6 h, resulting in severe hepatotoxicity, until returning to control levels at 20 h. The level of hepatic ferritin, especially the H-subunit, increased 20 h after diquat treatment due to elevated hepatic ferritin-H mRNA expression. These results indicate that early elevate... Biometals journals http://www.medworm.com/rss/comments.php?id=5038436 Wed, 22 Jun 2011 23:00:00 +0100 5038436 http://www.medworm.com/index.php?rid=5038438&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21691834%26dopt%3DAbstract Authors: Zhu Y, Xu J, Sun H, Hu C, Zhao H, Shao B, Bah AA, Li Y PMID: 21691834 [PubMed - as supplied by publisher] (Source: Biometals) Biometals journals http://www.medworm.com/rss/comments.php?id=5038438 Mon, 20 Jun 2011 23:00:00 +0100 5038438 http://www.medworm.com/index.php?rid=5038439&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21691833%26dopt%3DAbstract Authors: Hedberg Y, Hedberg J, Liu Y, Wallinder IO Iron, chromium, nickel, and manganese released from gas-atomized AISI 316L stainless steel powders (sized <45 and <4 μm) were investigated in artificial lysosomal fluid (ALF, pH 4.5) and in solutions of its individual inorganic and organic components to determine its most aggressive component, elucidate synergistic effects, and assess release mechanisms, in dependence of surface changes using atomic absorption spectroscopy, Raman, XPS, and voltammetry. Complexation is the main reason for metal release from 316L particles immersed in ALF. Iron was mainly released, while manganese was preferentially released as a consequence of the reduction of manganese oxide on the surface. These processes resulted in highly complexing media in... Biometals journals http://www.medworm.com/rss/comments.php?id=5038439 Fri, 17 Jun 2011 23:00:00 +0100 5038439 http://www.medworm.com/index.php?rid=4945575&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21655943%26dopt%3DAbstract We report here the case of a patient affected by heavy metal intoxication, who had developed an autoimmune disease. There was evidence of aluminium, cadmium and lead intoxication in a 63-year old Italian woman affected by rheumatoid arthritis (RA). We treated the patient with calcium disodium edetate (EDTA) once a week for a year in order to remove traces of heavy metal intoxication. Oxidative status profile was carried out at the beginning and after 6 months' EDTA chelation. At the end of the treatment, the patient did not show any signs of metal intoxication, RA symptoms and oxidative status improved. PMID: 21655943 [PubMed - as supplied by publisher] (Source: Biometals) Biometals journals http://www.medworm.com/rss/comments.php?id=4945575 Tue, 07 Jun 2011 23:00:00 +0100 4945575 http://www.medworm.com/index.php?rid=4945576&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21643731%26dopt%3DAbstract Authors: Martin LW, Reid DW, Sharples KJ, Lamont IL The lungs of patients with cystic fibrosis become chronically infected with the bacterium Pseudomonas aeruginosa, which heralds progressive lung damage and a decline in health. Iron is a crucial micronutrient for bacteria and its acquisition is a key factor in infection. P. aeruginosa can acquire this element by secreting pyoverdine and pyochelin, iron-chelating compounds (siderophores) that scavenge iron and deliver it to the bacteria. Siderophore-mediated iron uptake is generally considered a key factor in the ability of P. aeruginosa to cause infection. We have investigated the amounts of pyoverdine in 148 sputum samples from 36 cystic fibrosis patients (30 infected with P. aeruginosa and 6 as negative controls). Pyoverdine was pre... Biometals journals http://www.medworm.com/rss/comments.php?id=4945576 Fri, 03 Jun 2011 23:00:00 +0100 4945576 http://www.medworm.com/index.php?rid=4896028&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21625890%26dopt%3DAbstract Authors: Höckner M, Stefanon K, de Vaufleury A, Monteiro F, Pérez-Rafael S, Palacios O, Capdevila M, Atrian S, Dallinger R Variable environmental availability of metal ions represents a constant challenge for most organisms, so that during evolution, they have optimised physiological and molecular mechanisms to cope with this particular requirement. Metallothioneins (MTs) are proteins that play a major role in metal homeostasis and as a reservoir. The MT gene/protein systems of terrestrial helicid snails are an invaluable model for the study of metal-binding features and MT isoform-specific functionality of these proteins. In the present study, we characterised three paralogous MT isogenes and their expressed products in the escargot (Cantareus aspersus). The metal-dependent transcri... Biometals journals http://www.medworm.com/rss/comments.php?id=4896028 Mon, 30 May 2011 23:00:00 +0100 4896028 http://www.medworm.com/index.php?rid=4896029&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21618062%26dopt%3DAbstract Authors: Li Y, Lu L, Zhu M, Wang Q, Yuan C, Xing S, Fu X, Mei Y A series of copper complexes with multi-benzimidazole derivatives, including mono- and di-nuclear, were synthesized and characterized by Fourier transform IR spectroscopy, UV-Vis spectroscopy, elemental analysis, electrospray ionization mass spectrometry. The speciation of Cu/NTB in aqueous solution was investigated by potentiometric pH titrations. Their inhibitory effects against human protein tyrosine phosphatase 1B (PTP1B), T-cell protein tyrosine phosphatase (TCPTP), megakaryocyte protein tyrosine phosphatase 2 (PTP-MEG2), srchomology phosphatase 1 (SHP-1) and srchomology phosphatase 2 (SHP-2) were evaluated in vitro. The five copper complexes exhibit potent inhibition against PTP1B, TCPTP and PTP-MEG2 with almost same... Biometals journals http://www.medworm.com/rss/comments.php?id=4896029 Thu, 26 May 2011 23:00:00 +0100 4896029 http://www.medworm.com/index.php?rid=4896030&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21607695%26dopt%3DAbstract Authors: Liu Y, Han F, Xie Y, Wang Y Lactoferricin B (LfcinB), a 25 residue peptide derived from the N-terminal of bovine lactoferrin (bLF), causes depolarization of the cytoplasmic membrane in susceptible bacteria. Its mechanism of action, however, still needs to be elucidated. In the present study, synthetic LfcinB (without a disulfide bridge) and LfcinB (C-C; with a disulfide bridge) as well as three derivatives with 15-, 11- and 9-residue peptides were prepared to investigate their antimicrobial nature and mechanisms. The antimicrobial properties were measured via minimum inhibitory concentration (MIC) determinations, killing kinetics assays and synergy testing, and hemolytic activities were assessed by hemoglobin release. Finally, the morphology of peptide-treated bacteria was det... Biometals journals http://www.medworm.com/rss/comments.php?id=4896030 Mon, 23 May 2011 23:00:00 +0100 4896030 http://www.medworm.com/index.php?rid=4896031&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21604169%26dopt%3DAbstract Authors: Veeramani S, Baskaralingam V Artemia is a tiny marine crustacean, serves as an excellent tool in both basic and applied aspects of stress biology research. In the current manuscript, we report that Artemia parthenogenetica embryos (cysts), in diapause stage, undergo iron transition changes when exposed to chemical diapause deactivation stimulus (hydrogen peroxide). X-ray surface analysis of A. parthenogenetica embryos exposed to H(2)O(2) showed significant transitional changes in iron, as seen in cyst cross-sections. Electron paramagnetic resonance study revealed that upon H(2)O(2) exposure, increased nitric oxide (NO) production was observed in non-decapsulated cysts (ND), but not in decapsulated cysts (DC) (shell-removed cysts). Spin trapping studies also showed an increase ... Biometals journals http://www.medworm.com/rss/comments.php?id=4896031 Sat, 21 May 2011 23:00:00 +0100 4896031 http://www.medworm.com/index.php?rid=4850715&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21594680%26dopt%3DAbstract Authors: Bonilla-Ramirez L, Jimenez-Del-Rio M, Velez-Pardo C The biometals iron (Fe), manganese (Mn) and copper (Cu) have been associated to Parkinson's disease (PD) and Parkinsonism. In this work, we report for the first time that acute (15 mM for up to 5 days) or chronic (0.5 mM for up to 15 days) Fe, Mn and Cu exposure significantly reduced life span and locomotor activity (i.e. climbing capabilities) in Drosophila melanogaster. It is shown that the concentration of those biometals dramatically increase in Drosophila's brain acutely or chronically fed with metal. We demonstrate that the metal accumulation in the fly's head is associated with the neurodegeneration of several dopaminergic neuronal clusters. Interestingly, it is found that the PPL2ab DAergic neuronal cluster was er... Biometals journals http://www.medworm.com/rss/comments.php?id=4850715 Wed, 18 May 2011 23:00:00 +0100 4850715 http://www.medworm.com/index.php?rid=4850717&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21584710%26dopt%3DAbstract Authors: Pathak A, Sharma V, Kumar S, Dhawan DK Diabetes is a life threatening disease and its onset is linked with both environmental and genetic factors. Zinc metabolism gets altered during diabetes and results in many complications. The present study was designed to elucidate the effects of zinc supplementation on the biokinetics of (65)Zn in whole body, liver and its biodistribution in diabetic rats. The animals were divided into four groups viz; normal control; diabetic (single intraperitoneal injection of alloxan 150 mg/kg body weight); zinc treated (227 mg/l in drinking water); and diabetic + zinc treated. To carry out biokinetics study, each rat was injected intraperitoneally with 0.74 MBq radioactivity of (65)Zn following 4 weeks of different treatments and the radioacti... Biometals journals http://www.medworm.com/rss/comments.php?id=4850717 Mon, 16 May 2011 23:00:00 +0100 4850717 http://www.medworm.com/index.php?rid=4850716&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21584711%26dopt%3DAbstract Authors: Schreiber HD, Jones AH, Lariviere CM, Mayhew KM, Cain JB Red, purple, and blue sepals on selected cultivars of Hydrangea macrophylla were analyzed for their aluminum content. This content was determined to be a function of the sepal color with red sepals possessing 0-10 μg Al/g fresh sepal, purple sepals having 10-40 μg Al/g fresh sepal, and blue sepals containing greater than 40 μg Al/g fresh sepal. Accordingly, the threshold aluminum content needed to change H. macrophylla sepals from red to blue was about 40 μg Al/g fresh sepal. Higher aluminum concentrations were incorporated into the sepals, but this additional aluminum did not affect the intensity or hue of the blue color. These observations agreed with a chemical model proposing that the concentration of the blu... Biometals journals http://www.medworm.com/rss/comments.php?id=4850716 Mon, 16 May 2011 23:00:00 +0100 4850716 http://www.medworm.com/index.php?rid=4850718&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21562773%26dopt%3DAbstract Authors: Mangabeira PA, Ferreira AS, de Almeida AA, Fernandes VF, Lucena E, Souza VL, Dos Santos Júnior AJ, Oliveira AH, Grenier-Loustalot MF, Barbier F, Silva DC The aim of the present study was to identify the sites of accumulation of Cr in the species of macrophytes that are abundant in the Cachoeira river, namely, Alternanthera philoxeroides, Borreria scabiosoides, Polygonum ferrugineum and Eichhornia crassipes. Plants were grown in nutritive solution supplemented with 0.25 and 50 mg l(-1) of CrCl(3)·6H(2)O. Samples of plant tissues were digested with HNO(3)/HCl in a closed-vessel microwave system and the concentrations of Cr determined using inductively-coupled plasma mass spectrometry (ICP-MS). The ultrastructure of root, stem and leaf tissue was examined using transmission e... Biometals journals http://www.medworm.com/rss/comments.php?id=4850718 Wed, 11 May 2011 23:00:00 +0100 4850718 http://www.medworm.com/index.php?rid=4850719&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21553242%26dopt%3DAbstract In conclusion, the presence of Zn in the substrate caused a significant reduction in the oxidative stress induced by Hg. PMID: 21553242 [PubMed - as supplied by publisher] (Source: Biometals) Biometals journals http://www.medworm.com/rss/comments.php?id=4850719 Sat, 07 May 2011 23:00:00 +0100 4850719 http://www.medworm.com/index.php?rid=4797284&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21538067%26dopt%3DAbstract Authors: Barton LL PMID: 21538067 [PubMed - as supplied by publisher] (Source: Biometals) Biometals journals http://www.medworm.com/rss/comments.php?id=4797284 Mon, 02 May 2011 23:00:00 +0100 4797284 http://www.medworm.com/index.php?rid=4797286&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21533671%26dopt%3DAbstract Authors: Rivera-Mancía S, Ríos C, Montes S Manganese (Mn) is an essential metal for life. It is a key constituent of clue enzymes in the central nervous system, contributing to antioxidant defenses, energetic metabolism, ammonia detoxification, among other important functions. Until now, Mn transport mechanisms are partially understood; however, it is known that it shares some mechanisms of transport with iron. CNS is susceptible to Mn toxicity because it possesses mechanisms that allow Mn entry and favor its accumulation. Cases of occupational Mn exposure have been extensively reported in the literature; however, there are other ways of exposure, such as long-term parental nutrition and liver failure. Manganism and hepatic encephalopathy are the most common pathologies associated wi... Biometals journals http://www.medworm.com/rss/comments.php?id=4797286 Sat, 30 Apr 2011 23:00:00 +0100 4797286 http://www.medworm.com/index.php?rid=4797285&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21533903%26dopt%3DAbstract Authors: Banni M, Chouchene L, Said K, Kerkeni A, Messaoudi I The present study was designed to elucidate the protective effect mechanism of Zinc (Zn) and Selenium (Se) on cadmium (Cd)-induced oxidative stress in zebrafish. For this purpose we investigate the response of oxidative stress markers, metallothionein accumulation and gene expression in liver and ovary of female zebrafish exposed to 0,4 mg/l Cd in water and supplemented with Zn (5 mg kg(-1)) and/or Se (2 mg kg(-1)) for 21 days in their diet. Liver and ovary Cd uptake was evaluated after the exposure period. Cd exposure significantly inhibited the antioxidant enzyme activities termed as catalase (CAT), superoxide dismutase (SOD) and glutathione peroxydase (GPx) and caused a pronounced malondialdehyde (MDA) accumulation in... Biometals journals http://www.medworm.com/rss/comments.php?id=4797285 Sat, 30 Apr 2011 23:00:00 +0100 4797285 http://www.medworm.com/index.php?rid=4797287&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21503682%26dopt%3DAbstract Authors: Hernández-Franco P, Silva M, Valverde M, Rojas E Even though the molecular mechanisms by which lead induces toxicity and cancer have been intensely studied for many years, its carcinogenic mechanisms are not well understood yet. Several possible mechanisms have been examined to gain understanding on the carcinogenic properties of lead, which include mitogenesis, alteration of gene expression, and oxidative damage, among others. The aim of the present study was to explore the induction of oxidative damage at low lead concentrations using human embryonic hepatic cells WRL-68. Our results showed induction of reactive oxygen species, changes in the superoxide dismutase and catalase activity, as well as an induction of lipidperoxidation and DNA damage. However, after 5 weeks of e... Biometals journals http://www.medworm.com/rss/comments.php?id=4797287 Mon, 18 Apr 2011 23:00:00 +0100 4797287 http://www.medworm.com/index.php?rid=4797289&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21479831%26dopt%3DAbstract Authors: Kurt O, Ozden TY, Ozsoy N, Tunali S, Can A, Akev N, Yanardag R In recent years, the role of free radical damage consequent to oxidative stress is widely discussed in diabetic complications. In this aspect, the protection of cell integrity by trace elements is a topic to be investigated. Vanadium is a trace element believed to be important for normal cell function and development. The aim of the present study was to investigate the effect of vanadyl sulfate supplementation on the antioxidant system in the muscle tissue of diabetic rats. Diabetes was induced by intraperitoneal injection of streptozotocin (STZ, 65 mg/kg body weight) to male Swiss albino rats. The rats were randomly divided into 4 groups: Group I, control; Group II, vanadyl sulfate control; Group III, STZ-diabeti... Biometals journals http://www.medworm.com/rss/comments.php?id=4797289 Sat, 09 Apr 2011 23:00:00 +0100 4797289 http://www.medworm.com/index.php?rid=4797288&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21479832%26dopt%3DAbstract Authors: Bleackley MR, Macgillivray RT Transition metal ions are essential nutrients to all forms of life. Iron, copper, zinc, manganese, cobalt and nickel all have unique chemical and physical properties that make them attractive molecules for use in biological systems. Many of these same properties that allow these metals to provide essential biochemical activities and structural motifs to a multitude of proteins including enzymes and other cellular constituents also lead to a potential for cytotoxicity. Organisms have been required to evolve a number of systems for the efficient uptake, intracellular transport, protein loading and storage of metal ions to ensure that the needs of the cells can be met while minimizing the associated toxic effects. Disruptions in the cellular systems ... Biometals journals http://www.medworm.com/rss/comments.php?id=4797288 Sat, 09 Apr 2011 23:00:00 +0100 4797288 http://www.medworm.com/index.php?rid=4797290&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21476019%26dopt%3DAbstract In this study, α-methyl trans cinnamaldehyde, a less irritating derivative, have been self coupled and complexed with Co(II) and Ni(II) to generate N, N'-Bis (α-methyl trans cinnamadehyde) ethylenediimine [C(22)H(24)N(2)], [Co(C(44)H(48)N(4))Cl(2)] and [Ni(C(44)H(48)N(4))Cl(2)]. Ligand and complexes were characterized on the basis of FTIR, ESI-MS, IR and (1)HNMR techniques. Synthesized ligand [L] and complexes were investigated for their MICs, inhibition of ergosterol biosynthesis and H(+) extrusion against three strains of Candida: C. albicans 44829, C. tropicalis 750 and C. krusei 6258. Average of three species MIC of methyl cinnamaldehyde is 317 μg/ml (2168 μM). Compared to methyl cinnamaldehyde ligand [L], Co(II) and Ni(II) complex are found to be 4.48, 17.78 and 21.46 times more... Biometals journals http://www.medworm.com/rss/comments.php?id=4797290 Thu, 07 Apr 2011 23:00:00 +0100 4797290 http://www.medworm.com/index.php?rid=4687578&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21472415%26dopt%3DAbstract Authors: Tuccari G, Barresi G Lactoferrin (LF) is an iron-binding glycoprotein of the transferrin family, today known to have multifunctional physiological activities. In humans, under normal conditions, LF has been found in blood, mucosal secretions, gastrointestinal fluids, urine and mostly in milk and colostrum. The first pioneering immunohistochemical report about LF distribution in human tissues dated in 1978; successively, many studies have been performed to analyze the LF immunohistochemical pattern in different normal and neoplastic tissues. In this review, we present data from literature concerning the evidence of LF in tumors together with those by us obtained during more than 25 years; the immunohistochemical applications to human neoplastic tissues have been done to investi... Biometals journals http://www.medworm.com/rss/comments.php?id=4687578 Wed, 06 Apr 2011 23:00:00 +0100 4687578 http://www.medworm.com/index.php?rid=4687577&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21472416%26dopt%3DAbstract Authors: Morais PV, Branco R, Francisco R Large-scale industrial use of chromium (Cr) resulted in widespread environmental contamination with hexavalent chromium (Cr(VI)). The ability of microorganisms to survive in these environments and detoxify chromate requires the presence of specific resistance systems. Several Cr(VI) resistant species, belonging to a variety of genera, have been isolated in recent years. Ochrobactrum tritici strain 5bvl1 is a model for a highly Cr(VI)-resistant and reducing microorganism, with different strategies to cope with chromium. The strain contains the transposon-located (TnOtChr) chromate resistance genes chrB, chrA, chrC, chrF. The chrB and chrA genes were found to be essential for the establishment of high resistance but not chrC or chrF genes. Other ... Biometals journals http://www.medworm.com/rss/comments.php?id=4687577 Wed, 06 Apr 2011 23:00:00 +0100 4687577 http://www.medworm.com/index.php?rid=4687580&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21468620%26dopt%3DAbstract Authors: Robic C, Catoen S, De Goltstein MC, Idée JM, Port M PMID: 21468620 [PubMed - as supplied by publisher] (Source: Biometals) Biometals journals http://www.medworm.com/rss/comments.php?id=4687580 Tue, 05 Apr 2011 23:00:00 +0100 4687580 http://www.medworm.com/index.php?rid=4687579&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21468621%26dopt%3DAbstract In this report, we evaluated the in vivo metal ions release of three alloys (stainless steel, titanium and nickel-free) usually used in the orthodontics treatments and its genotoxicity. We applied to 15 patients, between 12 and 16 years, 4 tubes and 20 brackets. Samples from oral mucosa were taken before the treatment and 30 days later. The concentration of the titanium, chromium, manganese, cobalt, nickel, molybdenum and iron were detected using inductively coupled plasma mass spectrometry (ICP-MS). The genotoxicity was measured with a comet assay (Olive moment). The oral mucosa cells in contact with the stainless steel alloy displayed the greatest titanium and manganese concentrations and those in contact with the nickel-free alloy presented the greatest concentration of chromium and i... Biometals journals http://www.medworm.com/rss/comments.php?id=4687579 Tue, 05 Apr 2011 23:00:00 +0100 4687579 http://www.medworm.com/index.php?rid=4687581&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21465178%26dopt%3DAbstract Authors: Hua H, Günther V, Georgiev O, Schaffner W Copper is an integral part of a number of proteins and thus an essential trace metal. However, free copper ions can be highly toxic and every organism has to carefully control its bioavailability. Eukaryotes contain three copper chaperones; Atx1p/Atox1 which delivers copper to ATP7 transporters located in the trans-Golgi network, Cox17 which provides copper to the mitochondrial cytochrome c oxidase, and CCS which is a copper chaperone for superoxide dismutase 1. Here we describe the knockout phenotype of the Drosophila homolog of mammalian Atox1 (ATX1 in yeast). Atox1-/- flies develop normally, though at reduced numbers, and the eclosing flies are fertile. However, the mutants are unable to develop on low-copper food. Furthermore, the... Biometals journals http://www.medworm.com/rss/comments.php?id=4687581 Mon, 04 Apr 2011 23:00:00 +0100 4687581 http://www.medworm.com/index.php?rid=4687582&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21461949%26dopt%3DAbstract Authors: Gagoś M, Czernel G, Kamiński DM, Kostro K The aim of this research is to investigate amphotericin B (AmB)-Cu(2+) complexes in aqueous solution at different pH values. Electronic absorption, circular dichroism (CD), Raman and FTIR spectroscopies were used in this study. We found that different concentrations of AmB and Cu(2+) ions in solution leads to formation of complexes with stoichiometry of 2:1 and 1:1. The formation of AmB-Cu(2+) complexes at physiological pH values is accompanied by changes of the molecular organization of AmB especially disaggregation. These observed effects might be significant from a medical point of view. PMID: 21461949 [PubMed - as supplied by publisher] (Source: Biometals) Biometals journals http://www.medworm.com/rss/comments.php?id=4687582 Sat, 02 Apr 2011 23:00:00 +0100 4687582 http://www.medworm.com/index.php?rid=4687583&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21455662%26dopt%3DAbstract Authors: Kawanai T, Fujinaga M, Koizumi K, Kurotani I, Hashimoto E, Satoh M, Imai S, Miyoshi N, Oyama Y Although cadmium-induced apoptosis of lymphocytes is one of common features in the immunotoxicity of cadmium, the membrane pathway for intracellular cadmium accumulation is not fully elucidated. To characterize membrane Cd(2+) transport of rat thymocytes, the change in intracellular Cd(2+) concentration under various conditions was examined by the use of Fluo-3, a fluorescent probe for monitoring the change in intracellular concentration of divalent metal cations. The membrane Cd(2+) transport was estimated by the augmentation of Fluo-3 fluorescence induced by bath application of CdCl(2). Lowering temperature strongly suppressed the augmentation of Fluo-3 fluorescence by CdCl(2), sug... Biometals journals http://www.medworm.com/rss/comments.php?id=4687583 Thu, 31 Mar 2011 23:00:00 +0100 4687583 http://www.medworm.com/index.php?rid=4631955&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21432624%26dopt%3DAbstract Authors: Ferroni FM, Rivas MG, Rizzi AC, Lucca ME, Perotti NI, Brondino CD The purification and biochemical characterization of the respiratory membrane-bound nitrate reductase from Sinorhizobium meliloti 2011 (Sm NR) is reported together with the optimal conditions for cell growth and enzyme production. The best biomass yield was obtained under aerobic conditions in a fed-batch system using Luria-Bertani medium with glucose as carbon source. The highest level of Sm NR production was achieved using microaerobic conditions with the medium supplemented with both nitrate and nitrite. Sm NR is a mononuclear Mo-protein belonging to the DMSO reductase family isolated as a heterodimeric enzyme containing two subunits of 118 and 45 kDa. Protein characterization by mass spectrometry showed hom... Biometals journals http://www.medworm.com/rss/comments.php?id=4631955 Thu, 24 Mar 2011 00:00:00 +0100 4631955 http://www.medworm.com/index.php?rid=4631956&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21431358%26dopt%3DAbstract This study was conducted to assess effects of aluminum (Al) exposure on allergic responsive reactions and humoral immune function in rats. Forty male Wistar rats (5 weeks old) weighed 110-120 g were randomly allocated into four groups and were orally exposed to 0, 64.18, 128.36, and 256.72 mg/kg body weight aluminum trichloride in drinking water for 120 days. The levels of immunoglobulin (Ig) G, IgA, IgM, IgE, Complement factor (C)3, and C4 in serum were determined by ELISA and nephelometric assays at the end of experiment. The results showed that the levels of IgM, C3, and C4 were lowered, and the levels of IgG, IgA, and IgE were increased in an Al-dose dependent manner. The increased in IgE level and the decreased in C3 and C4 levels indicate that Al induces allergic responses in rat... Biometals journals http://www.medworm.com/rss/comments.php?id=4631956 Wed, 23 Mar 2011 00:00:00 +0100 4631956 http://www.medworm.com/index.php?rid=4631957&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21424779%26dopt%3DAbstract Authors: Lamore SD, Wondrak GT Zinc ion homeostasis plays an important role in human cutaneous biology where it is involved in epidermal differentiation and barrier function, inflammatory and antimicrobial regulation, and wound healing. Zinc-based compounds designed for topical delivery therefore represent an important class of cutaneous therapeutics. Zinc pyrithione (ZnPT) is an FDA-approved microbicidal agent used worldwide in over-the-counter topical antimicrobials, and has also been examined as an investigational therapeutic targeting psoriasis and UVB-induced epidermal hyperplasia. Recently, we have demonstrated that cultured primary human skin keratinocytes display an exquisite sensitivity to nanomolar ZnPT concentrations causing induction of heat shock response gene expression a... Biometals journals http://www.medworm.com/rss/comments.php?id=4631957 Tue, 22 Mar 2011 00:00:00 +0100 4631957 http://www.medworm.com/index.php?rid=4631958&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21424617%26dopt%3DAbstract Authors: Carrière P, Mantha M, Champagne-Paradis S, Jumarie C Cadmium (Cd) is a toxic metal with an extremely long half-life in humans. The intestinal absorption of Cd has been extensively studied but the role the intestinal epithelium may play in metal excretion has never been considered. The basolateral (BL)-to-apical (AP) transepithelial transport of Cd was characterized in TC7 human intestinal cells. Both AP and BL uptakes varied with days in culture, and BL uptake was twofold higher compared to AP in differentiated cultures. A 50% increase in the BL uptake of 0.5 μM (109)Cd was observed at pH 8.5 in a chloride but not nitrate medium, suggesting the involvement of a pH-sensitive mechanism of transport for chloro-complexes. Fe and Zn inhibited the BL uptake of Cd whereas complexa... Biometals journals http://www.medworm.com/rss/comments.php?id=4631958 Sun, 20 Mar 2011 00:00:00 +0100 4631958 http://www.medworm.com/index.php?rid=4631959&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21404021%26dopt%3DAbstract Authors: Nakajima KI, Kanno Y, Nakamura M, Gao XD, Kawamura A, Itoh F, Ishisaki A Lactoferrin (LF) belongs to the transferrin family and is present in several physiological fluids, including milk and colostrum. LF has recently been identified as an anabolic factor for bone. Here we investigated whether bovine LF (bLF) induces synthesis of angiogenic factors by osteoblasts. If so, we examined the underlying mechanism. We found that bLF purified from milk increased the mRNA expression of vascular endothelial growth factor (VEGF) and fibroblast growth factor-2 (FGF2) in murine osteoblast-like MC3T3-E1 cells and primary murine osteoblasts in a time- and dose-dependent manner. Furthermore, bLF increased VEGF and FGF2 protein levels in MC3T3-E1 cells. In addition, treatment of MC3T3-E1 cells... Biometals journals http://www.medworm.com/rss/comments.php?id=4631959 Tue, 15 Mar 2011 00:00:00 +0100 4631959 http://www.medworm.com/index.php?rid=4631960&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21399939%26dopt%3DAbstract Authors: Nevitt T Iron acquisition is a bona fide virulence determinant. The successful colonization of the mammalian host requires that microorganisms overcome the Fe aridity of this milieu in which the levels of circulating Fe are maintained exceedingly low both through the compartmentalization of this nutrient within cells as well as the tight binding of Fe to host circulating proteins and ligands. Microbes notoriously employ multiple strategies for high affinity Fe acquisition from the host that rely either on the expression of receptors for host Fe-binding proteins and ligands, its reduction by cell surface reductases or the utilization of siderophores, small organic molecules with very high affinity for Fe(3+). This review will discuss the multiple mechanisms deployed by fungal p... Biometals journals http://www.medworm.com/rss/comments.php?id=4631960 Sun, 13 Mar 2011 00:00:00 +0100 4631960 http://www.medworm.com/index.php?rid=4631961&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21399938%26dopt%3DAbstract Authors: Kustusch RJ, Kuehl CJ, Crosa JH The Vibrios are a unique group of bacteria inhabiting a vast array of aquatic environments. Many Vibrio species are capable of infecting a wide assortment of hosts. Some of these species include V. parahaemolyticus, V. alginolyticus, V. vulnificus, V. anguillarum, and V. cholerae. The ability of these organisms to utilize iron is essential in establishing both an infection in their hosts as well as surviving in the environment. Bacteria are able to sequester iron through the secretion of low molecular weight iron chelators termed siderophores. The iron-siderophore complexes are bound by specific outer membrane receptors and are brought through both the outer and inner membranes of the cell. The energy needed to drive this active transport is ach... Biometals journals http://www.medworm.com/rss/comments.php?id=4631961 Sat, 12 Mar 2011 00:00:00 +0100 4631961 http://www.medworm.com/index.php?rid=4631964&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21390523%26dopt%3DAbstract Authors: Volentini SI, Farías RN, Rodríguez-Montelongo L, Rapisarda VA Copper is both an essential nutrient and a toxic element able to catalyze free radicals formation which damage lipids and proteins. Although the available copper redox species in aerobic environment is Cu(II), proteins that participate in metal homeostasis use Cu(I). With isolated Escherichia coli membranes, we have previously shown that electron flow through the respiratory chain promotes cupric ions reduction by NADH dehydrogenase-2 and quinones. Here, we determined Cu(II)-reductase activity by whole cells using strains deficient in these respiratory chain components. Measurements were done by the appearance of Cu(I) in the supernatants of cells exposed to sub-lethal Cu(II) concentrations. In the absence of quin... Biometals journals http://www.medworm.com/rss/comments.php?id=4631964 Thu, 10 Mar 2011 00:00:00 +0100 4631964 http://www.medworm.com/index.php?rid=4631962&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21390525%26dopt%3DAbstract This study investigated the possible ligand exchange role played by phosphate in the dechelation mechanism. Omniscan(®) dechelation was monitored in vitro by relaxivity measurements performed at physiological pH with different concentrations of phosphate buffer and in the presence of endogenous cations. Dechelation experiments performed on phosphate buffer alone showed that phosphate may induce gadolinium release by ligand exchange when the phosphate concentration in the buffer is higher than 130 mM for an Omniscan(®) concentration of 1.25 mM. This corresponds to a Gd/phosphate ratio of 10(-2). This ratio could be reached in vivo, especially in deep compartments such as bone. The presence of endogenous cations (Zn(2+), Cu(2+) or Ca(2+)) has also been demonstrated to accelerate the kine... Biometals journals http://www.medworm.com/rss/comments.php?id=4631962 Thu, 10 Mar 2011 00:00:00 +0100 4631962 http://www.medworm.com/index.php?rid=4631963&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21390524%26dopt%3DAbstract Authors: Borovička J, Kubrová J, Rohovec J, Randa Z, Dunn CE Concentrations of uranium, thorium and rare earth elements (REE) in 36 species of ectomycorrhizal (26 samples) and saprobic (25 samples) macrofungi from unpolluted sites with differing bedrock geochemistry were analyzed by inductively coupled plasma mass spectrometry (ICP-MS). Analytical results are supported by use of certified reference materials (BCR-670, BCR-667, NIST-1575a) and the reliability of the determination of uranium was verified by epithermal neutron activation analysis (ENAA). It appears that data recently published on these elements are erroneous, in part because of use of an inappropriate analytical method; and in part because of apparent contamination by soil particles resulting in elevated levels of thori... Biometals journals http://www.medworm.com/rss/comments.php?id=4631963 Wed, 09 Mar 2011 00:00:00 +0100 4631963 http://www.medworm.com/index.php?rid=4570354&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21387113%26dopt%3DAbstract Authors: McEvoy MM, Rensing C PMID: 21387113 [PubMed - as supplied by publisher] (Source: Biometals) Biometals journals http://www.medworm.com/rss/comments.php?id=4570354 Wed, 09 Mar 2011 00:00:00 +0100 4570354 http://www.medworm.com/index.php?rid=4570355&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21384090%26dopt%3DAbstract Authors: Nandakumar R, Espirito Santo C, Madayiputhiya N, Grass G Metallic copper surfaces have strong antimicrobial properties and kill bacteria, such as Escherichia coli, within minutes in a process called contact killing. These bacteria are exposed to acute copper stress under dry conditions which is different from chronic copper stress in growing liquid cultures. Currently, the physiological changes of E. coli during the acute contact killing process are largely unknown. Here, a label-free, quantitative proteomic approach was employed to identify the differential proteome profiles of E. coli cells after sub-lethal and lethal exposure to dry metallic copper. Of the 509 proteins identified, 110 proteins were differentially expressed after sub-lethal exposure, whereas 136 proteins ha... Biometals journals http://www.medworm.com/rss/comments.php?id=4570355 Tue, 08 Mar 2011 00:00:00 +0100 4570355 http://www.medworm.com/index.php?rid=4570356&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21380607%26dopt%3DAbstract Authors: Burkhead JL, Gray LW, Lutsenko S Wilson's disease (WD) is a severe disorder of copper misbalance, which manifests with a wide spectrum of liver pathology and/or neurologic and psychiatric symptoms. WD is caused by mutations in a gene encoding a copper-transporting ATPase ATP7B and is accompanied by accumulation of copper in tissues, especially in the liver. Copper-chelation therapy is available for treatment of WD symptoms and is often successful, however, significant challenges remain with respect to timely diagnostics and treatment of the disease. The lack of genotype-phenotype correlation remains unexplained, the causes of fulminant liver failure are not known, and the treatment of neurologic symptoms is only partially successful, underscoring the need for better understand... Biometals journals http://www.medworm.com/rss/comments.php?id=4570356 Sat, 05 Mar 2011 00:00:00 +0100 4570356 http://www.medworm.com/index.php?rid=4570357&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21373826%26dopt%3DAbstract Authors: Riadh N, Allagui MS, Bourogaa E, Vincent C, Croute F, Elfeki A Since the worldwide approval of lithium therapy in 1970, lithium has been used for its anti-manic, antidepressant, and anti-suicidal effects. The last decade has witnessed the following discoveries about its neuroprotective and neurotrophic properties, yet the therapeutic mechanisms at the cellular level remain not-fully defined. We have undertaken the present study to determine if chronic lithium treatment, at therapeutically relevant concentrations, exerts neurotrophic/neuroprotective effects in the mouse brain in vivo. For this purpose, 10 months aged mice were fed for 3 months on food pellets contained 1 g (L1 group) or 2 g (L2 group) lithium carbonate/kg, resulting in serum concentrations of 0.4 and 0.8 m... Biometals journals http://www.medworm.com/rss/comments.php?id=4570357 Fri, 04 Mar 2011 00:00:00 +0100 4570357 http://www.medworm.com/index.php?rid=4570358&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21359534%26dopt%3DAbstract Authors: Frazer DM, Darshan D, Anderson GJ The maintenance of appropriate iron levels is important for mammalian health, particularly during the rapid growth period following birth. Too little iron can lead to irreversible damage to the developing central nervous system and too much iron at this point can have adverse long term consequences, possibly due to excessive free radical production. In order to maintain iron levels, intestinal iron absorption is very efficient in young mammals, such that almost all of the iron in breast milk is utilized. However this high level of absorption is unable to be down regulated in response to excess iron as it can be in adults, implying that different regulatory processes are involved during suckling. Various mechanisms have been proposed to explain... Biometals journals http://www.medworm.com/rss/comments.php?id=4570358 Sat, 26 Feb 2011 00:00:00 +0100 4570358 http://www.medworm.com/index.php?rid=4570360&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21350949%26dopt%3DAbstract Authors: Oshtrakh MI, Berkovsky AL, Kumar A, Kundu S, Vinogradov AV, Konstantinova TS, Semionkin VA A comparative study of oxyhemoglobins from pig, rabbit, normal human and patients with blood system malignant diseases was performed using Mössbauer spectroscopy with a high velocity resolution at 90 K. Mössbauer spectra were fitted with the help of two models: using one quadrupole doublet (model of equivalent iron electronic structure in α- and β-subunits of hemoglobins) and superposition of two quadrupole doublets (model of non-equivalent iron electronic structure in α- and β-subunits of hemoglobins). The results obtained using both models demonstrated small variations of hyperfine parameters that were related to the heme iron state variation in different hemoglobins. These resu... Biometals journals http://www.medworm.com/rss/comments.php?id=4570360 Fri, 25 Feb 2011 00:00:00 +0100 4570360 http://www.medworm.com/index.php?rid=4570359&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21350950%26dopt%3DAbstract Authors: Yoshimura E, Kohdr H, Mori S, Hider RC The phytosiderophores, mugineic acid (MA) and epi-hydroxymugineic acid (HMA), together with a related compound, nicotianamine (NA), were investigated for their ability to bind Al(III). Potentiometric titration analysis demonstrated that MA and HMA bind Al(III), in contrast to NA which does not under normal physiological conditions. With MA and HMA, in addition to the Al complex (AlL), the protonated (AlLH) and deprotonated (AlLH(-1)) complexes were identified from an analysis of titration curves, where L denotes the phytosiderophore form in which all the carboxylate functions are ionized. The equilibrium formation constants of the Al(III) phytosiderophore complexes are much smaller than those of the corresponding Fe(III) complexes. The hi... Biometals journals http://www.medworm.com/rss/comments.php?id=4570359 Fri, 25 Feb 2011 00:00:00 +0100 4570359 http://www.medworm.com/index.php?rid=4570362&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21347851%26dopt%3DAbstract Authors: St Denis M, Sonier B, Robinson R, Scott FW, Cameron DW, Lee BC Haemophilus ducreyi, a gram-negative and heme-dependent bacterium, is the causative agent of chancroid, a genital ulcer sexually transmitted infection. Heme acquisition in H. ducreyi proceeds via a receptor mediated process in which the initial event involves binding of hemoglobin and heme to their cognate outer membrane proteins, HgbA and TdhA, respectively. Following this specific interaction, the fate of the periplasmic deposited heme is unclear. Using protein expression profiling of the H. ducreyi periplasmic proteome, a periplasmic-binding protein, termed hHbp, was identified whose expression was enhanced under heme-limited conditions. The gene encoding this protein was situated in a locus displaying genetic c... Biometals journals http://www.medworm.com/rss/comments.php?id=4570362 Thu, 24 Feb 2011 00:00:00 +0100 4570362 http://www.medworm.com/index.php?rid=4570361&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21347852%26dopt%3DAbstract Authors: Lu J, Wang W, Tan G, Landry AP, Yi P, Si F, Ren Y, Ding H Escherichia coli topoisomerase I (TopA) cleaves and rejoins one strand of double-stranded DNA to relax the negatively supercoiled DNA. Structurally, TopA contains an N-terminal catalytic fragment and a C-terminal zinc-binding region that is required for relaxation of the negatively supercoiled DNA. Here we report that E. coli TopA is an iron and zinc binding protein. The UV-Vis absorption measurements and metal content analyses reveal that TopA purified from E. coli cells grown in the rich LB medium contains both iron and zinc. However, TopA purified from E. coli cells grown in the M9 minimal medium has negligible amounts of zinc or iron and no topoisomerase activity. Nevertheless, supplement of exogenous zinc or iron i... Biometals journals http://www.medworm.com/rss/comments.php?id=4570361 Thu, 24 Feb 2011 00:00:00 +0100 4570361 http://www.medworm.com/index.php?rid=4515779&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21344194%26dopt%3DAbstract Authors: Yang Z, Wang Y, Yang G Copper (II) complex of formulation [Cu-Phen-Tyr](H(2)O)](ClO(4)) (Phen = 1,10-phenanthroline, L: -Tyr = L: -tyrosine), has been prepared, and their induced DNA oxidative cleavage activity studied. The complex binds to DNA by intercalation, as deduced from the absorption and fluorescence spectral data. Scatchard plots constructed from the absorption titration data gave binding constant 2.44 × 10(4) M(-1) of base pairs. Extensive hypochromism, broadening, and red shifts in the absorption spectra were observed. Upon binding to DNA, the fluorescence from the DNA-ethidium bromide system was efficiently quenched by the copper (II) complex. Stern-Volmer quenching constant 0.61 × 10(3) M(-1) obtained from the linear quenching plots. [Cu-Phen-Tyr] com... Biometals journals http://www.medworm.com/rss/comments.php?id=4515779 Wed, 23 Feb 2011 00:00:00 +0100 4515779 http://www.medworm.com/index.php?rid=4515780&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21327478%26dopt%3DAbstract Authors: Yen CC, Shen CJ, Hsu WH, Chang YH, Lin HT, Chen HL, Chen CM Escherichia coli (E. coli) are the most common aerobic gram-negative bacilli in a normal intestinal tract. They cause most of the intra-abdominal infections, wound infections associated with abdominal surgery, and septicemia. Most of these infections are of endogenous intestinal origin. Lactoferrin (LF) is an iron-binding glycoprotein found in milk and various external secretions. This protein has been found to have a number of biological functions, including antimicrobial, anti-cancer, antioxidant, and immunomodulatory effects. Partial degradation of LF by pepsin can give rise to peptides termed lactoferricin (LFcin) with more potent antimicrobial activity. LF and LFcin have been shown to inhibit the growth of a numb... Biometals journals http://www.medworm.com/rss/comments.php?id=4515780 Wed, 16 Feb 2011 00:00:00 +0100 4515780 http://www.medworm.com/index.php?rid=4456672&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21301930%26dopt%3DAbstract This article reviews the properties of different bacterial (and archaeal) transporters for sulfate, molybdate, and related oxyanions. Sulfate uptake is carried out by sulfate permeases that belong to the SulT (CysPTWA), SulP, CysP/(PiT), and CysZ families. The oxyanions molybdate, tungstate, selenate and chromate are structurally related to sulfate. Molybdate is transported mainly by the high-affinity ModABC system and tungstate by the TupABC and WtpABC systems. CysPTWA, ModABC, TupABC, and WtpABC are homologous ATP-binding cassette (ABC)-type transporters with similar organization and properties. Uptake of selenate and chromate oxyanions occurs mainly through sulfate permeases. PMID: 21301930 [PubMed - as supplied by publisher] (Source: Biometals) Biometals journals http://www.medworm.com/rss/comments.php?id=4456672 Tue, 08 Feb 2011 00:00:00 +0100 4456672 http://www.medworm.com/index.php?rid=4456674&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21293906%26dopt%3DAbstract Authors: Sadraie M, Missirlis F Mutations in single Drosophila melanogaster genes can alter total body metal accumulation. We therefore asked whether evolutionary constraints maintain biologically abundant metal ions (iron, copper, manganese and zinc) to similar concentrations in different species of Drosophilidae, or whether metal homeostasis is a highly adaptable trait as shown previously for triglyceride and glycogen storage. To avoid dietary influences, only species able to grow and reproduce on a standard laboratory medium were selected for analysis. Flame atomic absorption spectrometry was used to determine metal content in 5-days-old adult flies. Overall, the data suggest that the metallome of the nine species tested is well conserved. Meaningful average values for the Drosophil... Biometals journals http://www.medworm.com/rss/comments.php?id=4456674 Fri, 04 Feb 2011 00:00:00 +0100 4456674 http://www.medworm.com/index.php?rid=4456673&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21293907%26dopt%3DAbstract Authors: Long XH, Yang PY, Liu Q, Yao J, Wang Y, He GH, Hong GY, Ni JZ Lanthanides (Lns) compounds have been reported to possess contrary effects on cell activity, i.e., promoting cell cycle progression and cell growth by lower concentration treatment, but suppressing cell proliferation and inducing cell apoptosis at higher dosing. However, the cellular processes during the intervention and the possible underlying mechanisms are still not well clarified. Using a combination of high-throughput liquid chromatography (LC) with mass spectrometry (MS), we have investigated the metabolomic profiles of Hela cells following gadolinium chloride (GdCl(3)) treatment in time- and concentration- dependent manners. A total of 48 metabolites released by Hela cells are identified to be differentially ... Biometals journals http://www.medworm.com/rss/comments.php?id=4456673 Fri, 04 Feb 2011 00:00:00 +0100 4456673 http://www.medworm.com/index.php?rid=4456675&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21286786%26dopt%3DAbstract Authors: Di Lorenzo M, Stork M, Crosa JH Anguibactin, the siderophore produced by Vibrio anguillarum 775 is synthesized from 2,3-dihydroxybenzoic acid (DHBA), cysteine and hydroxyhistamine via a nonribosomal peptide synthetase (NRPS) mechanism. Most of the genes encoding anguibactin biosynthetic proteins are harbored by the pJM1 plasmid. In this work we report the identification of a homologue of the plasmid-encoded angB on the chromosome of strain 775. The product of both genes harbor an isochorismate lyase (ICL) domain that converts isochorismic acid to 2,3-dihydro-2,3-dihydroxybenzoic acid, one of the steps of DHBA synthesis. We show in this work that both ICL domains are functional in the production of DHBA in V. anguillarum as well as in E. coli. Substitution by alanine of the asp... Biometals journals http://www.medworm.com/rss/comments.php?id=4456675 Tue, 01 Feb 2011 00:00:00 +0100 4456675 http://www.medworm.com/index.php?rid=4456676&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21279732%26dopt%3DAbstract Authors: Silver S Understanding of BioMetals developed basically from a starting point about 60 years ago to current mechanistic understanding of the biological behavior of many metal ions from protein structural and functional studies. Figure 1 shows a Biochemical Periodic Table, element by element, with requirements, roles and biochemistry of the specific ions indicated. With few exceptions, the biology is of the ions formed and not of the elemental state of each. Early BioMetals efforts defined nutritional growth needs for animals, plants and microbes for inorganic "macro-nutrients" such as magnesium, calcium, potassium, sodium, and phosphate and of "micronutrients" such as copper, iron, manganese and zinc. Surprises came early with regard to microbes, for example the finding that ... Biometals journals http://www.medworm.com/rss/comments.php?id=4456676 Sun, 30 Jan 2011 00:00:00 +0100 4456676 http://www.medworm.com/index.php?rid=4456677&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21274738%26dopt%3DAbstract Authors: Bieda R, Kitanovic I, Alborzinia H, Meyer A, Ott I, Wölfl S, Sheldrick WS The cytostatic properties of novel rhodium(III) thiacrown ether complexes [RhCl(LL)([9]aneS(3))](n+) with either aromatic κ(2) N ligands (n = 2) or anionic chelate ligands (n = 1) have been investigated for the human cancer cell lines HT-29 and MCF-7 and for immortalized HEK-293 cells. Taken together with literature IC(50) values for analogous complexes with polypyridyl ligands or 1,4-dithiane, the in vitro assays indicate that dicationic complexes with soft κ(2) N (imino) or κ(2) S (thiaether) ligands exhibit significantly higher antiproliferative effects than those with hard κ(2) N (amino) ligands. Dicationic complexes are more active than monocationic complexes with similar ligands. Pronounce... Biometals journals http://www.medworm.com/rss/comments.php?id=4456677 Fri, 28 Jan 2011 00:00:00 +0100 4456677 http://www.medworm.com/index.php?rid=4456678&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21267633%26dopt%3DAbstract Authors: Watt RK Iron is an essential trace nutrient required for the active sites of many enzymes, electron transfer and oxygen transport proteins. In contrast, to its important biological roles, iron is a catalyst for reactive oxygen species (ROS). Organisms must acquire iron but must protect against oxidative damage. Biology has evolved siderophores, hormones, membrane transporters, and iron transport and storage proteins to acquire sufficient iron but maintain iron levels at safe concentrations that prevent iron from catalyzing the formation of ROS. Ferritin is an important hub for iron metabolism because it sequesters iron during times of iron excess and releases iron during iron paucity. Ferritin is expressed in response to oxidative stress and is secreted into the extracellular ... Biometals journals http://www.medworm.com/rss/comments.php?id=4456678 Wed, 26 Jan 2011 00:00:00 +0100 4456678 http://www.medworm.com/index.php?rid=4456680&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21258843%26dopt%3DAbstract Authors: Honsa ES, Maresso AW During an infection, bacterial pathogens must acquire iron from the host to survive. However, free iron is sequestered in host proteins, which presents a barrier to iron-dependent bacterial replication. In response, pathogens have developed mechanisms to acquire iron from the host during infection. Interestingly, a significant portion of the iron pool is sequestered within heme, which is further bound to host proteins such as hemoglobin. The copious amount of heme-iron makes hemoglobin an ideal molecule for targeted iron uptake during infection. While the study of heme acquisition is well represented in Gram-negative bacteria, the systems and mechanism of heme uptake in Gram-positive bacteria has only recently been investigated. Bacillus anthracis, the cau... Biometals journals http://www.medworm.com/rss/comments.php?id=4456680 Sat, 22 Jan 2011 00:00:00 +0100 4456680 http://www.medworm.com/index.php?rid=4456679&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21258844%26dopt%3DAbstract Authors: Veldhuis NA, Kuiper MJ, Dobson RC, Pearson RB, Camakaris J The Menkes (ATP7A) P(1B)-type ATPase is a transmembrane copper-translocating protein. It contains six similar high-affinity metal-binding domains (MBDs) in the N-terminal cytoplasmic tail that are important for sensing intracellular copper and regulating ATPase function through the transfer of copper between domains. Molecular characterization of copper-binding and transfer is predominantly dependent on NMR structures derived from E. coli expression systems. A limitation of these models is the exclusion of post-translational modifications. We have previously shown that the third copper-binding domain, MBD3, uniquely contains two phosphorylated residues: Thr-327, which is phosphorylated only in the presence of elevated ... Biometals journals http://www.medworm.com/rss/comments.php?id=4456679 Sat, 22 Jan 2011 00:00:00 +0100 4456679 http://www.medworm.com/index.php?rid=4390547&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21243404%26dopt%3DAbstract Authors: Flora SJ, Pachauri V, Mittal M, Kumar D Epidemiological evidence demonstrates positive correlation between environmental and occupational arsenic or fluoride exposure and risk to various cardio-respiratory disorders. Arsenic-exposure has been associated with atherosclerosis, hypertension, cerebrovascular diseases, ischemic heart disease, and peripheral vascular disorders, whereas Fluoride-exposure manifests cardiac irregularities and low blood pressure (BP). Present study aims to study the combined effects of these toxicants on various cardio-respiratory variables in male rats. Single intravenous (i.v.) dose of arsenic (1, 5, 10 mg/kg) or fluoride (5, 10, 20, 36.5 mg/kg) either alone or in combination were administered. Individual exposure to arsenic or fluoride led to a sig... Biometals journals http://www.medworm.com/rss/comments.php?id=4390547 Tue, 18 Jan 2011 00:00:00 +0100 4390547 http://www.medworm.com/index.php?rid=4390548&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21240540%26dopt%3DAbstract Authors: Bishop YM, Barton LL, Johnson GV Iron metabolism in plants is essential to maintain optimal growth and iron nutrition is dependent on uptake of iron from the environment and movement of iron in the plant tissues. We have examined the translocation of iron in plant leaves following foliar application of FeEDTA to Vicia faba and Zea mays. Using radiolabeled iron, we observed that iron translocation is stimulated by products of Methylobacterium mesophylicum and by the cytokinin, kinetin. When cytokinins were applied to leaves along with (55)FeEDTA, the rate of iron translocation was greater than in controls without cytokinin addition. Since recent studies indicate that M. mesophylicum is widely distributed in the environment as a pyllospheric bacterium, this organism may have an ... Biometals journals http://www.medworm.com/rss/comments.php?id=4390548 Sat, 15 Jan 2011 00:00:00 +0100 4390548 http://www.medworm.com/index.php?rid=4390550&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21229380%26dopt%3DAbstract Authors: Pai AB, Conner T, McQuade CR, Olp J, Hicks P Intravenous (IV) iron supplementation is widely used to support erythropoeisis in hemodialysis patients. IV iron products are associated with oxidative stress that has been measured principally by circulating biomarkers such as products of lipid peroxidation. The pro-oxidant effects of IV iron are presumed to be due at least in part, by free or non-transferrin bound iron (NTBI). However, the effects of IV iron on intracellular redox status and downstream effectors is not known. This prospective, crossover study compared cytokine activation, reactive oxygen species generation and oxidative stress after single IV doses of iron sucrose and iron dextran. This was a prospective, open-label, crossover study. Ten patients with end-stage re... Biometals journals http://www.medworm.com/rss/comments.php?id=4390550 Thu, 13 Jan 2011 00:00:00 +0100 4390550 http://www.medworm.com/index.php?rid=4390549&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21229381%26dopt%3DAbstract Authors: Atkins JL, Gorbunov NV, Trabosh V, Van Duyne R, Kashanchi F, Komarov AM Extracellular iron has been implicated in the pathogenesis of post-injury organ failure. However, the source(s) and biochemical species of this iron have not been identified. Based upon evidence that distant organ injury results from an increase in intestinal permeability, we looked for ferrous iron in mesenteric lymph in anesthetized rats undergoing hemorrhage and fluid resuscitation (H/R). Ferrous iron increased in lymph from 4.7 nmol/mg of protein prior to hemorrhage to 86.6 nmol/mg during resuscitation. Utilizing immuno-spin trapping in protein fractions that were rich in iron, we tentatively indentified protein carrier(s) of ferrous iron by MALDI-TOF MS. One of the identified proteins was the metall... Biometals journals http://www.medworm.com/rss/comments.php?id=4390549 Thu, 13 Jan 2011 00:00:00 +0100 4390549 http://www.medworm.com/index.php?rid=4390552&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21221719%26dopt%3DAbstract Authors: Maret W Homeostatic control maintains essential transition metal ions at characteristic cellular concentrations to support their physiological functions and to avoid adverse effects. Zinc is especially widely used as a catalytic or structural cofactor in about 3000 human zinc proteins. In addition, the homeostatic control of zinc in eukaryotic cells permits functions of zinc(II) ions in regulation and in paracrine and intracrine signaling. Zinc ions are released from proteins through ligand-centered reactions in zinc/thiolate coordination environments, and from stores in cellular organelles, where zinc transporters participate in zinc loading and release. Muffling reactions allow zinc ions to serve as signaling ions (second messengers) in the cytosol that is buffered to picomo... Biometals journals http://www.medworm.com/rss/comments.php?id=4390552 Tue, 11 Jan 2011 00:00:00 +0100 4390552 http://www.medworm.com/index.php?rid=4390553&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21221718%26dopt%3DAbstract Authors: Reis DC, Pinto MC, Souza-Fagundes EM, Rocha LF, Pereira VR, Melo CM, Beraldo H Complexes [Sb(QN)(2)Cl] (1), [Sb(QC)(2)Cl] (2) and [Sb(QI)(2)Cl] (3) were obtained with 8-hydroxyquinoline (HQN), 5-chloro-8-hydroxyquinoline (HQC) and 5-chloro-7-iodo-8-hydroxyquinoline (clioquinol, HQI). The quinoline derivatives and their antimony(III) complexes were evaluated for their anti-trypanosomal activity as well as for their cytotoxicity against HL-60 and Jurkat human leukemia cell lines. Upon coordination to antimony(III) the anti-trypanosomal activity of HQC and HQI increases, the highest improvement being observed for complex (3), which was the most active among all studied compounds against both epimastigote and trypomastigote forms of Trypanosoma cruzi. All quinoline derivatives pro... Biometals journals http://www.medworm.com/rss/comments.php?id=4390553 Sun, 09 Jan 2011 00:00:00 +0100 4390553 http://www.medworm.com/index.php?rid=4390551&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21221720%26dopt%3DAbstract Authors: Sato J, Takeda K, Nishiyama R, Watanabe T, Abo M, Yoshimura E, Nakagawa J, Abe A, Kawasaki S, Niimura Y We purified free flavin-independent NADPH oxidoreductase from Synechocystis sp. PCC6803 based on NADPH oxidation activity elicited during reduction of t-butyl hydroperoxide in the presence of Fe(III)-EDTA. The N-terminal sequencing of the purified enzyme revealed it to be ferredoxin-NADP(+) oxidoreductase (FNR( S )). The purified enzyme reacted with cytochrome c, ferricyanide and 2,6-dichloroindophenol (DCIP). The substrate specificity of the enzyme was similar to the known FNR. DNA degradation occurring in the presence of NADPH, Fe(III)-EDTA and hydrogen peroxide was potently enhanced by the purified enzyme, indicating that Synechocystis FNR( S ) may drive the Fenton reacti... Biometals journals http://www.medworm.com/rss/comments.php?id=4390551 Sat, 08 Jan 2011 00:00:00 +0100 4390551 http://www.medworm.com/index.php?rid=4390554&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21213119%26dopt%3DAbstract Authors: Boserup MW, Lichota J, Haile D, Moos T Iron is crucial for a variety of cellular functions in neuronal cells. Neuronal iron uptake is reflected in a robust and consistent expression of transferrin receptors and divalent metal transporter 1 (DMT 1). Conversely, the mechanisms by which neurons neutralize and possibly excrete iron are less clear. Studies indicate that neurons express ferroportin which could reflect a mechanism for iron export. We mapped the distribution of ferroportin in the adult mouse brain using an antibody prepared from a peptide representing amino acid sequences 223-303 of mouse ferroportin. The antibody specifically detected ferroportin in brain homogenates, whereas homogenates of cultured endothelial cells were devoid of immunoreactivity. In brain sections... Biometals journals http://www.medworm.com/rss/comments.php?id=4390554 Fri, 07 Jan 2011 00:00:00 +0100 4390554 http://www.medworm.com/index.php?rid=4390555&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21210186%26dopt%3DAbstract Authors: Raimunda D, González-Guerrero M, Leeber BW, Argüello JM Cu(+)-ATPases play a key role in bacterial Cu(+) homeostasis by participating in Cu(+) detoxification and cuproprotein assembly. Characterization of Archaeoglobus fulgidus CopA, a model protein within the subfamily of P(1B-1) type ATPases, has provided structural and mechanistic details on this group of transporters. Atomic resolution structures of cytoplasmic regulatory metal binding domains (MBDs) and catalytic actuator, phosphorylation, and nucleotide binding domains are available. These, in combination with whole protein structures resulting from cryo-electron microscopy analyses, have enabled the initial modeling of these transporters. Invariant residues in helixes 6, 7 and 8 form two transmembrane metal binding si... Biometals journals http://www.medworm.com/rss/comments.php?id=4390555 Thu, 06 Jan 2011 00:00:00 +0100 4390555 http://www.medworm.com/index.php?rid=4390558&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21207115%26dopt%3DAbstract Authors: Vinckx T, Wei Q, Matthijs S, Noben JP, Daniels R, Cornelis P In Pseudomonas aeruginosa the response to oxidative stress is orchestrated by the LysR regulator OxyR by activation of the transcription of two catalase genes (katA and katB), of the alkyl-hydroxyperoxidases ahpCF and ahpB. Next to the expected high sensitivity to oxidative stress generated by reactive oxygen species (ROS: H(2)O(2), O(2) (-)), the oxyR mutant shows a defective growth under conditions of iron limitation (Vinckx et al. 2008). Although production and uptake of the siderophore pyoverdine is not affected by the absence of oxyR, the mutant is unable to satisfy its need for iron when grown under iron limiting conditions. In order to get a better insight into the effects caused by iron limitation on the phys... Biometals journals http://www.medworm.com/rss/comments.php?id=4390558 Wed, 05 Jan 2011 00:00:00 +0100 4390558 http://www.medworm.com/index.php?rid=4390557&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21207116%26dopt%3DAbstract This study was aimed to evaluate the effect of aqueous seed extract of Sc (ASc) on MeHg-induced toxicity in rats. Two-day-old rats (P2) received a single dose of MeHg (10 mg/kg) and two doses of ASc (0.9 mg/kg) per os. After two days, the effects of the treatment were investigated in the cerebral cortex, hippocampus, kidney, liver and urine samples. Our results demonstrated that N-acetyl-β-D: -glucosaminidase (NAG) activity in the kidney and urine, the lipid peroxidation levels in the liver and kidney samples, as well as the adenosine deaminase (ADA) activity in the hippocampus, kidney and liver were higher in MeHg-group when compared to the control group. The administration of ASc reverted the toxic effects of MeHg. It is noteworthy to observe that the main compounds present in the ASc... Biometals journals http://www.medworm.com/rss/comments.php?id=4390557 Wed, 05 Jan 2011 00:00:00 +0100 4390557 http://www.medworm.com/index.php?rid=4390556&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21207117%26dopt%3DAbstract Authors: Ou BR, Jiang MJ, Lin CH, Liang YC, Lee KJ, Yeh JY As an essential trace element, selenium (Se) deficiency results in White Muscle Disease in livestock and Keshan disease in humans. The main objectives of this study were to clone and characterize the chicken selenoprotein W (SeW) gene and investigate SeW mRNA expression in chicken tissues. The deduced amino acid (AA) sequence of chicken SeW contains 85 AAs with UAG as the stop codon. Like all SeW genes identified in different species, chicken SeW contains one well-conserved selenocysteine (Sec) at the 13th position encoded by the UGA codon. The proposed glutathione (GSH)-binding site at the Cys(37) of SeW is not conserved in the chicken, but Cys(9) and Sec(13), with possible GSH binding, are conserved in SeWs identified from al... Biometals journals http://www.medworm.com/rss/comments.php?id=4390556 Wed, 05 Jan 2011 00:00:00 +0100 4390556 http://www.medworm.com/index.php?rid=4303036&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21188474%26dopt%3DAbstract Authors: Youard ZA, Wenner N, Reimmann C The bacterial siderophore pyochelin is composed of salicylate and two cysteine-derived heterocycles, the second of which is modified by reduction and N-methylation during biosynthesis. In Pseudomonas aeruginosa, the first cysteine residue is converted to its D-isoform during thiazoline ring formation, whereas the second cysteine remains in its L-configuration. Stereochemistry is opposite in the Pseudomonas fluorescens siderophore enantio-pyochelin, in which the first ring originates from L-cysteine and the second ring from D-cysteine. Both siderophores promote growth of the producer organism during iron limitation and induce the expression of their biosynthesis genes by activating the transcriptional AraC-type regulator PchR. However, neither si... Biometals journals http://www.medworm.com/rss/comments.php?id=4303036 Sat, 25 Dec 2010 00:00:00 +0100 4303036 http://www.medworm.com/index.php?rid=4303035&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21188475%26dopt%3DAbstract Authors: Abdul Ajees A, Yang J, Rosen BP Arsenic, a toxic metalloid widely existing in the environment, causes a variety of health problems. The ars operon encoded by Escherichia coli plasmid R773 has arsD and arsA genes, where ArsA is an ATPase that is the catalytic subunit of the ArsAB As(III) extrusion pump, and ArsD is an arsenic chaperone for ArsA. ArsD transfers As(III) to ArsA and increases the affinity of ArsA for As(III), allowing resistance to environmental concentrations of arsenic. Cys12, Cys13 and Cys18 in ArsD form a three sulfur-coordinated As(III) binding site that is essential for metallochaperone activity. ATP hydrolysis by ArsA is required for transfer of As(III) from ArsD to ArsA, suggesting that transfer occurs with a conformation of ArsA that transiently forms dur... Biometals journals http://www.medworm.com/rss/comments.php?id=4303035 Sat, 25 Dec 2010 00:00:00 +0100 4303035 http://www.medworm.com/index.php?rid=4303037&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21184140%26dopt%3DAbstract Authors: Majtan T, Frerman FE, Kraus JP Toxicity in Escherichia coli resulting from high concentrations of cobalt has been explained by competition of cobalt with iron in various metabolic processes including Fe-S cluster assembly, sulfur assimilation, production of free radicals and reduction of free thiol pool. Here we present another aspect of increased cobalt concentrations in the culture medium resulting in the production of cobalt protoporphyrin IX (CoPPIX), which was incorporated into heme proteins including membrane-bound cytochromes and an expressed human cystathionine beta-synthase (CBS). The presence of CoPPIX in cytochromes inhibited their electron transport capacity and resulted in a substantially decreased respiration. Bacterial cells adapted to the increased cobalt conce... Biometals journals http://www.medworm.com/rss/comments.php?id=4303037 Fri, 24 Dec 2010 00:00:00 +0100 4303037 http://www.medworm.com/index.php?rid=4303038&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21181488%26dopt%3DAbstract Authors: Bafana A Mercuric reductase (MerA) enzyme plays an important role in biogeochemical cycling and detoxification of Hg and recently, has also been shown to be useful in clean up of Hg-contaminated effluents. Present study describes isolation of a heavy metal-resistant isolate of Sporosarcina, which could tolerate up to 40, 525, 210, 2900 and 370 μM of Cd, Co, Zn, Cr and Hg respectively. It was found to reduce and detoxify redox-active metals like Cr and Hg. The chromate reductase and MerA activities in the crude cell extract of the culture were 1.5 and 0.044 units/mg protein respectively. The study also describes designing of a new set of highly degenerate primers based on a dataset of 23 Firmicute merA genes. As the primers encompass the known diversity of merA genes within ... Biometals journals http://www.medworm.com/rss/comments.php?id=4303038 Thu, 23 Dec 2010 00:00:00 +0100 4303038 http://www.medworm.com/index.php?rid=4303039&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21170571%26dopt%3DAbstract Authors: Li JL, Li HX, Li S, Jiang ZH, Xu SW, Tang ZX Selenoprotein W (SelW) and selenium (Se) plays important roles in gastrointestinal function and that SelW expression in the gastrointestinal system of mammals is sensitive to Se levels. However, little is known about the pattern of SelW expression in the bird gastrointestinal tract. To investigate the distribution of SelW and effects of dietary Se levels on the SelW mRNA expression in the gastrointestinal tract tissues of birds, 1-day-old male chickens were fed either a commercial diet or a Se-supplemented diet containing 1.0, 2.0, 3.0 or 5.0 mg/kg sodium selenite for 90 days. The gastrointestinal tract tissues (tongue, esophagus, crop, proventriculus, gizzard, duodenum, small intestine, cecum and rectum) were collected and examin... Biometals journals http://www.medworm.com/rss/comments.php?id=4303039 Sat, 18 Dec 2010 00:00:00 +0100 4303039 http://www.medworm.com/index.php?rid=4303040&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21153861%26dopt%3DAbstract Authors: Checa SK, Soncini FC Gold ions are mobilized and disseminated through the environment and enter into the cells by non-specific intake. To avoid deleterious effect that occurs even at very low concentrations, bacteria such as Salmonella enterica and Cupriavidus metallidurans use Au-specific MerR-type transcriptional regulators to detect the presence of these toxic ions, and control the expression of specific resistance factors. In contrast to the related copper sensor CueR, the Au-selective metalloregulatory proteins are able to distinguish Au(I) from Cu(I) or Ag(I). This is achieved by finely tuning a single dithiolate metal coordination with conserved cysteine residues at the metal binding site of the proteins to lower the affinity for Cu(I) in comparison to the Cu-sensors, w... Biometals journals http://www.medworm.com/rss/comments.php?id=4303040 Tue, 14 Dec 2010 00:00:00 +0100 4303040 http://www.medworm.com/index.php?rid=4245731&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21140194%26dopt%3DAbstract Authors: Arciello M, Capo CR, D'Annibale S, Cozzolino M, Ferri A, Carrì MT, Rossi L The role of copper in the toxicity of mutant copper-dependent enzyme superoxide dismutase (SOD1) found in patients affected with the familial form of amyotrophic lateral sclerosis (fALS) is widely debated. Here we report that treatment of human neuroblastoma cells SH-SY5Y with a specific copper chelator, triethylene tetramine (Trien) induces the decrease of intracellular copper level, paralleled by decreased activity of SOD1. A comparable effect is observed in mouse NSC-34-derived cells, a motoneuronal model, transfected for the inducible expression of either wild-type or G93A mutant human SOD1, one of the mutations associated with fALS. In both cell types, the drop of SOD1 activity is not paralleled b... Biometals journals http://www.medworm.com/rss/comments.php?id=4245731 Wed, 08 Dec 2010 00:00:00 +0100 4245731 http://www.medworm.com/index.php?rid=4213353&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21110220%26dopt%3DAbstract This study is conducted to find any correlation between serum iron level and low bone mass in sickle cell anemia (SCA). Patients ≥18 years of age with sickle cell anemia, who attended outpatient clinics or admitted to King Fahd University Hospital, Al Khobar, Saudi Arabia,between 1st September 2006 and August 2007 were the subjects of this study. Patients age and sex were documented and body mass index was calculated. Apart from routine hematological tests, serum ferritin, serum Iron level, total estradiol, testosterone level was done. Bone mineral density measurement was done using dual energy X-ray absorptiometry (DEXA) at upper femur and lumbar spine. The data of 100 patients was analyzed, 48 males and 52 females. The mean age was 27.5 ± 6.1 years. In 64 patients (32 males and 32 ... Biometals journals http://www.medworm.com/rss/comments.php?id=4213353 Fri, 26 Nov 2010 00:00:00 +0100 4213353 http://www.medworm.com/index.php?rid=4213354&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21103911%26dopt%3DAbstract Authors: Bergeron RJ, Wiegand J, Bharti N, McManis JS, Singh S The current solution to iron-mediated damage in transfusional iron overload disorders is decorporation of excess unmanaged metal, chelation therapy. The clinical development of the tridentate chelator deferitrin (1, Table 1) was halted due to nephrotoxicity. It was then shown by replacing the 4'-(HO) of 1 with a 3,6,9-trioxadecyloxy group, the nephrotoxicity could be ameliorated. Further structure-activity relationship studies have established that the length and the position of the polyether backbone controlled: (1) the ligand's iron clearing efficiency (ICE), (2) chelator tissue distribution, (3) biliary ferrokinetics, and (4) tissue iron reduction. The current investigation compares the ICE and tissue distribution of a ... Biometals journals http://www.medworm.com/rss/comments.php?id=4213354 Sat, 20 Nov 2010 00:00:00 +0100 4213354 http://www.medworm.com/index.php?rid=4198131&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21088870%26dopt%3DAbstract Authors: Daidone I, Magliano A, Di Nola A, Mignogna G, Clarkson MM, Lizzi AR, Oratore A, Mazza F Lactoferricins are potent antimicrobial peptides released by pepsin cleavage of Lactoferrins. Bovine Lactoferricin (LfcinB) has higher activity than the intact bovine Lactoferrin, and is the most active among the other Lactoferricins of human, murine and caprine origin. In the intact protein the fragment corresponding to LfcinB is in an helical conformation, while in water LfcinB adopts an amphipathic β-hairpin structure. However, whether any of these structural motifs is the antibacterial active conformation, i.e., the one interacting with bacterial membrane components, remains to be seen. Here we present Circular Dichroism (CD) spectra and Molecular Dynamics (MD) simulations indicating t... Biometals journals http://www.medworm.com/rss/comments.php?id=4198131 Fri, 19 Nov 2010 00:00:00 +0100 4198131 http://www.medworm.com/index.php?rid=4181363&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21080032%26dopt%3DAbstract Authors: Hartney SL, Mazurier S, Kidarsa TA, Quecine MC, Lemanceau P, Loper JE The soil bacterium Pseudomonas fluorescens Pf-5 produces two siderophores, a pyoverdine and enantio-pyochelin, and its proteome includes 45 TonB-dependent outer-membrane proteins, which commonly function in uptake of siderophores and other substrates from the environment. The 45 proteins share the conserved β-barrel and plug domains of TonB-dependent proteins but only 18 of them have an N-terminal signaling domain characteristic of TonB-dependent transducers (TBDTs), which participate in cell-surface signaling systems. Phylogenetic analyses of the 18 TBDTs and 27 TonB-dependent receptors (TBDRs), which lack the N-terminal signaling domain, suggest a complex evolutionary history including horizontal transfer... Biometals journals http://www.medworm.com/rss/comments.php?id=4181363 Tue, 16 Nov 2010 00:00:00 +0100 4181363 http://www.medworm.com/index.php?rid=4163957&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21053054%26dopt%3DAbstract In conclusion, our study, in contrast to the no-effect results published from the parent study, further establishes the sensitivity and specificity of specific urinary porphyrins as a biomarker for low-level Hg body-burden, and also reveals that dental amalgams are a significant chronic contributor to Hg body-burden. PMID: 21053054 [PubMed - as supplied by publisher] (Source: Biometals) Biometals journals http://www.medworm.com/rss/comments.php?id=4163957 Fri, 05 Nov 2010 00:00:00 +0100 4163957 http://www.medworm.com/index.php?rid=4134798&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21046200%26dopt%3DAbstract In this study, Coffea arabica L. cell suspension cultures were exposed to excess Fe (60 and 240 μM) to investigate changes in the gene expression of ferritin and antioxidant enzymes. Iron content accumulated during cell growth, and Western blot analysis showed an increase of ferritin in cells treated with Fe. The expression of two ferritin genes retrieved from the Brazilian coffee EST database was studied. CaFER1, but not CaFER2, transcripts were induced by Fe exposure. Phylogenetic analysis revealed that CaFER1 is not similar to CaFER2 or to any ferritin that has been characterised in detail. The increase in ferritin gene expression was accompanied by an increase in the activity of antioxidant enzymes. Superoxide dismutase, guaiacol peroxidase, catalase, and glutathione reductase activi... Biometals journals http://www.medworm.com/rss/comments.php?id=4134798 Wed, 03 Nov 2010 00:00:00 +0100 4134798 http://www.medworm.com/index.php?rid=4121413&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D20981470%26dopt%3DAbstract In this study, we evaluated a potential role in Mn(2+) detoxification by the Secretory Pathway Ca(2+), Mn(2+)-ATPase in rat liver and a liver-derived cell model WIF-B that polarizes to distinct bile canalicular and sinusoidal domains in culture. Of two known isoforms, only secretory pathway Ca(2+)-ATPase isoform 1 (SPCA1) was expressed in liver and WIF-B cells. As previously observed in non-polarized cells, SPCA1 showed overlapping distribution with TGN38, consistent with Golgi/TGN localization. However, a prominent novel localization of SPCA1 to an endosomal population close to, but not on the basolateral membrane was also observed. This was confirmed by fractionation of rat liver homogenates which revealed dual distribution of SPCA1 to the Golgi/TGN and a fraction that included the early... Biometals journals http://www.medworm.com/rss/comments.php?id=4121413 Thu, 28 Oct 2010 00:00:00 +0100 4121413 http://www.medworm.com/index.php?rid=4121412&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D20981471%26dopt%3DAbstract Authors: Haselwandter K, Häninger G, Ganzera M Despite indications that S. granulatus and S. luteus release iron-chelating compounds, the exact spectrum of ferric hydroxamates synthesized by these two Suillus species remained unclear. Hence the aim of this study was to identify all of the main siderophores produced by these two ectomycorrhizal fungal species under pure culture conditions. By means of HPLC and LC-MS analyses we show that S. granulatus releases cyclic and linear fusigen, ferrichrome, coprogen and triacetylfusarinine C into the nutrient medium, while S. luteus culture filtrates contain cyclic and linear fusigen, ferricrocin and coprogen. All of the different siderophores were identified on basis of reference compounds and their specific MS spectra which were recorded on ... Biometals journals http://www.medworm.com/rss/comments.php?id=4121412 Thu, 28 Oct 2010 00:00:00 +0100 4121412 http://www.medworm.com/index.php?rid=4121411&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D20981472%26dopt%3DAbstract Authors: Sawyer RT, Maier LA During the last decade, there have been concerted efforts to reduce beryllium (Be) exposure in the workplace and thereby reduce potential cases of this occupational lung disorder. Despite these efforts, it is estimated that there are at least one million Be-exposed individuals in the U.S. who are potentially at risk for developing chronic beryllium disease (CBD). Previously, we reviewed the current CBD literature and proposed that CBD represents a model interaction between innate and acquired immunity (Sawyer et al., Int Immunopharmacol 2:249-261, 2002). We closed this review with a section on "future directions" that identified key gaps in our understanding of the pathogenesis of CBD. In the intervening period, progress has been made to fill in some of the... Biometals journals http://www.medworm.com/rss/comments.php?id=4121411 Thu, 28 Oct 2010 00:00:00 +0100 4121411 http://www.medworm.com/index.php?rid=4121414&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D20978927%26dopt%3DAbstract Authors: Xu S, Zhang B, Cao ZY, Ling TF, Shen WB In animals, heme oxygenase (HO), a rate-limiting enzyme responsible for carbon monoxide (CO) production, was regarded as a protective system maintaining cellular homeostasis. It was also established that metal ions are powerful HO-inducing agents and cobalt chloride (CoCl(2)) was the first metal ion identified with an inducing property. Previous study suggests that CoCl(2) stimulates adventitious root formation in tomato and cucumber cuttings. In this test, we discover that both CoCl(2) and an inducer of HO-1, hemin, could lead to the promotion of lateral root development, as well as the induction of HO-1 protein expression, HO activity, or LeHO-1/2 transcripts, in lateral root initiation zone of tomato seedlings. The effect is specific ... Biometals journals http://www.medworm.com/rss/comments.php?id=4121414 Wed, 27 Oct 2010 00:00:00 +0100 4121414 http://www.medworm.com/index.php?rid=4106839&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D20957409%26dopt%3DAbstract Authors: Gurusamy KS, Farooqui N, Loizidou M, Dijk S, Taanman JW, Whiting S, Farquharson MJ, Fuller BJ, Davidson BR Trace elements are involved in many key pathways involving cell cycle control. The influence of zinc and zinc chelator (TPEN) on transcription levels of the main zinc transporters (ZnT1 and ZIP1) in the HT-29 colorectal cell line has not been reported. Proliferation of HT-29 cells was measured using the methylene blue assay after exposure to zinc (two concentrations), TPEN (two concentrations), or a combination of zinc and TPEN (simultaneously and sequentially) for 4 h, 8 h, and 24 h. The transcription levels of ZnT1, ZIP1, vascular endothelial growth factor (VEGF), and caspase-3 were determined using reverse transcriptase real-time polymerase chain reaction (RT-PCR) a... Biometals journals http://www.medworm.com/rss/comments.php?id=4106839 Mon, 18 Oct 2010 23:00:00 +0100 4106839 http://www.medworm.com/index.php?rid=4075046&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D20938718%26dopt%3DAbstract Authors: Li WR, Xie XB, Shi QS, Duan SS, Ouyang YS, Chen YB The antibacterial activity and mechanism of silver nanoparticles (Ag-NPs) on Staphylococcus aureus ATCC 6538P were investigated in this study. The experiment results showed the minimum bactericidal concentration (MBC) of Ag-NPs to S. aureus was 20 μg/ml. Moreover, when bacteria cells were exposed to 50 μg/ml Ag-NPs for 6 h, the cell DNA was condensed to a tension state and could have lost their replicating abilities. When S. aureus cells were exposed to 50 μg/ml Ag-NPs for 12 h, the cell wall was breakdown, resulting in the release of the cellular contents into the surrounding environments, and finally became collapsed. And Ag-NPs could reduce the enzymatic activity of respiratory chain dehydrogenase. Furthermore, the ... Biometals journals http://www.medworm.com/rss/comments.php?id=4075046 Mon, 11 Oct 2010 23:00:00 +0100 4075046 http://www.medworm.com/index.php?rid=4060112&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D20931265%26dopt%3DAbstract Authors: Bica L, Meyerowitz J, Parker SJ, Caragounis A, Du T, Paterson BM, Barnham KJ, Crouch PJ, White AR, Donnelly PS Brain tumors such as neuroblastomas and gliomas are often refractory to current treatments. Development of metal-based drugs may offer an alternative approach due to the ability to deliver radionuclides or cytotoxic metals to the tumor. Previous studies have shown that diacetyl-bis(N(4)-methylthiosemicarbazonato)-copper(II) (Cu(II)(atsm)) can selectively target hypoxic tumors and this feature has been utilized for development of imaging and radiotherapy. However, we have recently shown that glyoxal-bis(N(4)-methylthiosemicarbazonato)-copper(II) (Cu(II)(gtsm)) can target the brain in animal models of neurodegeneration. Unlike Cu(II)(atsm), Cu(II)(gtsm) is able to relea... Biometals journals http://www.medworm.com/rss/comments.php?id=4060112 Thu, 07 Oct 2010 23:00:00 +0100 4060112 http://www.medworm.com/index.php?rid=4024954&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D20872046%26dopt%3DAbstract Authors: Donpunha W, Kukongviriyapan U, Sompamit K, Pakdeechote P, Kukongviriyapan V, Pannangpetch P Cadmium (Cd) is one of the most important environmental pollutants that cause a number of adverse health effects in humans and animals. Recent studies have shown that Cd-induced oxidative damage within the vascular tissues results in vascular dysfunction. The current study was aimed to investigate whether ascorbic acid could protect against Cd-induced vascular dysfunction in mice. Male ICR mice were received CdCl(2) (100 mg/l) via drinking water for 8 weeks alone or received ascorbic acid supplementation at doses of 50 and 100 mg/kg/day for every other day. Results showed that Cd administration increased arterial blood pressure and blunted the vascular responses to vasoactive a... Biometals journals http://www.medworm.com/rss/comments.php?id=4024954 Fri, 24 Sep 2010 23:00:00 +0100 4024954 http://www.medworm.com/index.php?rid=4024957&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D20853137%26dopt%3DAbstract Authors: Vraspir JM, Holt PD, Butler A Marine bacterial isolates Vibrio sp. HC0601C5 and Halomonas meridiana str. HC4321C1 were isolated off the coast of southern California and were found to produce an expanded suite of previously identified amphiphilic siderophores. Specifically two new members of the amphibactin family, amphibactins S and T, which have a C14:1 ω-7 fatty acid and a saturated C12 fatty acid, respectively, were produced by Vibrio sp. HC0601C5. These siderophores are produced in addition to a number of previously described amphibactins and are excreted into the culture supernatant. Two new members of the aquachelin family of siderophores, aquachelins I and J, which have an hydroxylated C12 fatty acid and a saturated C10 fatty acid, respectively, were produced by Halo... Biometals journals http://www.medworm.com/rss/comments.php?id=4024957 Sat, 18 Sep 2010 23:00:00 +0100 4024957 http://www.medworm.com/index.php?rid=4024956&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D20853138%26dopt%3DAbstract The objective of the present study was to analyze the effects of aluminum on the activity of antioxidant enzymes such as catalase (CAT), superoxide dismutase (SOD), and ascorbate peroxidase (APX). Also was evaluated the lipid peroxidation, H(2)O(2) content, levels of ascorbic acid (ASA), non-protein thiols (NPSH) and Al content in three genotypes of oat, Avena sativa L. (UFRGS 930598, UFRGS 17, and UFRGS 280). The genotypes were grown in different concentrations of Al ranging from 90 to 555 μM for 5 days. The antioxidant system was unable to overcome toxicity resulting in negative effects such as lipid peroxidation and H(2)O(2) content in UFRGS 930598. The results showed that UFRGS 930598 was the most sensitive genotype. UFRGS 17 and UFRGS 280 were more resistant to Al toxicity. T... Biometals journals http://www.medworm.com/rss/comments.php?id=4024956 Sat, 18 Sep 2010 23:00:00 +0100 4024956 http://www.medworm.com/index.php?rid=4024955&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D20862522%26dopt%3DAbstract Authors: Stephens BW, Cook DR, Grusak MA To understand how plants from the Fabaceae family maintain zinc (Zn) homeostasis, we have characterized the kinetics of three Zn transporting proteins from the ZIP family of divalent metal transporters in the model legume Medicago truncatula. Of six ZIP's studied, MtZIP1, MtZIP5 and MtZIP6 were the only members from this family determined to transport Zn and were further characterized. MtZIP1 has a low affinity for Zn with a K(m) of 1 μM as compared to MtZIP5 and MtZIP6 that have a higher affinity for Zn with K(m) of 0.4 μM and 0.3 μM, respectively. Zn transport by MtZIP1 was more sensitive to inhibition by copper (Cu) concentrations than MtZIP5 and MtZIP6, because 3 μM Cu inhibited Zn transport by 80% in MtZIP1 while 5Â... Biometals journals http://www.medworm.com/rss/comments.php?id=4024955 Wed, 15 Sep 2010 23:00:00 +0100 4024955 http://www.medworm.com/index.php?rid=3981254&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D20844928%26dopt%3DAbstract Authors: Cui W, Fu G, Wu H, Shen W Following previous findings that cadmium (Cd) induces heme oxygenase-1 (HO1) gene expression in alfalfa seedling roots, we now show that the decreased glutathione (GSH) and ascorbic acid (AsA) contents, induction of HO-1 gene expression and its protein level by Cd was mimicked by a GSH depletor diethylmaleate (DEM). Meanwhile, above Cd- or DEM-induced decreased GSH content followed by HO-1 up-regulation could be strengthened or reversed differentially by the application of a selective inhibitor of GSH biosynthesis L: -buthionine-sulfoximine (BSO), or exogenous GSH and AsA, respectively. The antioxidative behavior of HO-1 induction was further confirmed by histochemical staining for the detection of loss of membrane integrity in a short period of treat... Biometals journals http://www.medworm.com/rss/comments.php?id=3981254 Wed, 15 Sep 2010 23:00:00 +0100 3981254 http://www.medworm.com/index.php?rid=3969918&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D20838856%26dopt%3DAbstract Authors: Souza VL, de Almeida AA, Lima SG, de M Cascardo JC, da C Silva D, Mangabeira PA, Gomes FP Cadmium (Cd) originating from atmospheric deposits, from industrial residues and from the application of phosphate fertilizers may accumulate in high concentrations in soil, water and food, thus becoming highly toxic to plants, animals and human beings. Once accumulated in an organism, Cd discharges and sets off a sequence of biochemical reactions and morphophysiological changes which may cause cell death in several tissues and organs. In order to test the hypothesis that Cd interferes in the metabolism of G. americana, a greenhouse experiment was conducted to measure eventual morphophysiological responses and cell death induced by Cd in this species. The plants were exposed to Cd concent... Biometals journals http://www.medworm.com/rss/comments.php?id=3969918 Mon, 13 Sep 2010 23:00:00 +0100 3969918 http://www.medworm.com/index.php?rid=3969919&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D20835752%26dopt%3DAbstract Authors: Pękal A, Biesaga M, Pyrzynska K Quercetin, one of the most common dietary flavonols, was investigated in the presence of Cu(II) ions in methanolic solution in order to obtain some explanation on the mechanism interaction and its action against free radical-mediated damage. The spectroscopic studies (UV-VIS, IR, ESI-MS) were used to assess the extent to which it undergo complex formation through chelation or modification through oxidation. The reaction of quercetin with Cu(II) resulted in the formation of 1:1 metal-ligand complex (λ(max) = 436 nm) through the carbonyl oxygen and 3-OH group in C ring. Then quercetin is oxidized to the benzoquinone type products. The addition of EDTA destroyed the complex but did not regenerate the whole original spectrum of querce... Biometals journals http://www.medworm.com/rss/comments.php?id=3969919 Fri, 10 Sep 2010 23:00:00 +0100 3969919 http://www.medworm.com/index.php?rid=3933665&cid=s_37611_60_f&fid=37611&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D20809125%26dopt%3DAbstract In this study, we found that zinc-induced ErbB2 protein expression and Akt activation are required for preventing reperfusion injury. Neonatal rat cardiac myocytes subjected to 8 h of hypoxia, followed by 16 h of reoxygenation induced cardiomyocyte apoptosis, as assessed by increased caspase-3 activity, annexin V staining and lowered MTT reduction and ATP levels. However, addition of zinc-pyrithione (ZPT) before onset of reoxygenation effectively lowered the apoptotic indices and restored the ATP levels. ZPT induced a significant increase in ErbB2 protein expression and Akt activation. Pretreatment with Hsp 90 inhibitor, geldanamycin or PI3-kinase inhibitor, wortmannin prevented the increase in ATP levels and abrogated the protective effect of zinc-pyrithione. Taken together, these data su... Biometals journals http://www.medworm.com/rss/comments.php?id=3933665 Mon, 30 Aug 2010 23:00:00 +0100 3933665