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This page shows you the most recent publications within this specialty of the MedWorm directory. This is page number 9.

Dexmedetomidine Controls Systemic Cytokine Levels through the Cholinergic Anti-inflammatory Pathway
This study intends to elucidate the anti-inflammatory mechanism of dexmedetomidine through the cholinergic anti-inflammatory pathway. To investigate this therapeutic potential of dexmedetomidine, a murine model of endotoxemia was established induced by lipopolysaccharide (LPS). Animals were assigned to one of four protocols. Protocol one: animals were randomly assigned to control group, dexmedetomidine group, and sterile saline group (n = 20 each), and these animals were used for survival analysis. The survival rate was assessed up to 120 h after endotoxin injection. Protocol two: animals were randomly assigned to one...
Source: Inflammation - September 29, 2014 Category: Biomedical Science Source Type: research

Protective Effects of Lactobacillus plantarum NDC 75017 Against Lipopolysaccharide-Induced Liver Injury in Mice
This study investigated the protective effect of Lactobacillus plantarum NDC 75017 (L. plantarum NDC 75017) against acute liver injury induced by lipopolysaccharide (LPS). Thirty male mice were randomly divided into the control, LPS, and LPS + L. plantarum NDC 75017 groups. In the LPS + L. plantarum group, the mice were orally pretreated with L. plantarum NDC 75017 for 15 days. At 16 days, the mice in the LPS and LPS + L. plantarum NDC 75017 groups were intraperitoneally injected with LPS at 4 mg/kg body weight, whereas the control mice were treated with an equal amount of saline. After 8 h, the serum alanine transamin...
Source: Inflammation - September 29, 2014 Category: Biomedical Science Source Type: research

The Link Between Unpredictable Chronic Mild Stress Model for Depression and Vascular Inflammation?
In this study, we investigated the effects of infliximab (a TNF-α inhibitor) on endothelium-dependent vascular reactivity, systemic blood pressure, and endothelial nitric oxide synthase (eNOS) immunoreactivity in the unpredictable chronic mild stress (UCMS) model of depression in rats. There was no significant change between all groups in the systemic blood pressure. In UCMS, endothelium-dependent relaxation of the smooth muscle in response to carbachol was significantly decreased with 50 % maximal response (E max) and pD2 values compared with the controls. Infliximab was able to reverse this UCMS effect. Rela...
Source: Inflammation - September 29, 2014 Category: Biomedical Science Source Type: research

Clinical Significance of Myeloid-Derived Suppressor Cells in Human Renal Transplantation with Acute T Cell-Mediated Rejection
In conclusion, we demonstrated a potential role for MDSCs in prolonging allograft survival after ATCMR, and this was associated with higher CD4+Foxp3+/CD4+IL-17+ ratio in PBMC. (Source: Inflammation)
Source: Inflammation - September 29, 2014 Category: Biomedical Science Source Type: research

Serum-Soluble HLA-G Is Associated with Specific IgE in Patients with Allergic Rhinitis and Asthma
Abstract Allergic rhinitis (AR) and allergic asthma (AA) are characterized by T helper (Th)2-polarized immune response. Soluble human leukocyte antigen G (sHLA-G) molecule plays an immunomodulatory activity. Previously, it has been reported that children with AR or AA had higher sHLA-G levels in comparison with normal subjects. Thus, the present study aimed at confirming these data in adults and investigating whether there was a relationship between serum sHLA-G levels and serum IgE levels, in patients with AR or AA. One hundred twenty symptomatic patients, suffering from respiratory symptoms, were enrolled: 45 n...
Source: Inflammation - September 29, 2014 Category: Biomedical Science Source Type: research

A mechanistic theory to explain the efficacy of antiretroviral therapy
Nature Reviews Microbiology 12, 772 (2014). doi:10.1038/nrmicro3351 Authors: Sarah B. Laskey & Robert F. Siliciano In the early years of the AIDS epidemic, a diagnosis of HIV-1 infection was equivalent to a death sentence. The development of combination antiretroviral therapy (cART) in the 1990s to combat HIV-1 infection was one of the most impressive achievements of medical science. Today, patients (Source: Nature Reviews Microbiology)
Source: Nature Reviews Microbiology - September 29, 2014 Category: Microbiology Authors: Sarah B. LaskeyRobert F. Siliciano Tags: Perspectives Source Type: research

Bicuspid aortic valves are associated with increased wall and turbulence shear stress levels compared to trileaflet aortic valves.
Abstract Congenital bicuspid aortic valves (BAVs) are associated with accelerated disease progression, such as leaflet calcification and ascending aorta dilatation. Although common underlying genetic factors have been implicated in accelerated disease in BAV patients, several studies have suggested that altered hemodynamics also play a role in this disease process. The present study compares turbulence and wall shear stress (WSS) measurements between various BAV and trileaflet aortic valve (TAV) models to provide information for mechanobiological models of BAV disease. BAV and TAV models were constructed from excis...
Source: Biomechanics and Modeling in Mechanobiology - September 28, 2014 Category: Biomedical Science Authors: Saikrishnan N, Mirabella L, Yoganathan AP Tags: Biomech Model Mechanobiol Source Type: research

Nano graphene oxide: A novel carrier for oral delivery of flavonoids.
Abstract The interesting physical and chemical properties of graphene oxide (GO) have led to much excitement among biomedical scientists in recent years. It is known that many potent, often aromatic medicines are water insoluble, and this has hindered their administration to treat diseases. Nano GO was synthesized and investigated for its biological application as a carrier for quercetin, a focused bioactive flavonoid widely used as a health supplement and a drug candidate. Different techniques were used to fully evaluate the synthesis, cytotoxicity, and quercetin loading capacity of nano GO. AFM and TEM results co...
Source: Colloids and Surfaces - September 28, 2014 Category: Biotechnology Authors: Rahmanian N, Hamishehkar H, Dolatabadi JE, Arsalani N Tags: Colloids Surf B Biointerfaces Source Type: research

Signaling mechanisms of the epithelial-mesenchymal transition.
Abstract The epithelial-mesenchymal transition (EMT) is an essential mechanism in embryonic development and tissue repair. EMT also contributes to the progression of disease, including organ fibrosis and cancer. EMT, as well as a similar transition occurring in vascular endothelial cells called endothelial-mesenchymal transition (EndMT), results from the induction of transcription factors that alter gene expression to promote loss of cell-cell adhesion, leading to a shift in cytoskeletal dynamics and a change from epithelial morphology and physiology to the mesenchymal phenotype. Transcription program switching in ...
Source: Science Signaling - September 27, 2014 Category: Biomedical Science Authors: Gonzalez DM, Medici D Tags: Sci Signal Source Type: research

Fibroblast growth factor receptor 1 is a key inhibitor of TGFβ signaling in the endothelium.
We reported that endothelial cell-specific knockout of fibroblast growth factor receptor 1 (FGFR1) led to activation of TGFβ signaling and development of EndMT in vitro and in vivo. Furthermore, EndMT in human diseased vasculature correlated with decreased abundance of FGFR1. These findings identify FGFR1 as the key regulator of TGFβ signaling and EndMT development. PMID: 25249657 [PubMed - in process] (Source: Science Signaling)
Source: Science Signaling - September 27, 2014 Category: Biomedical Science Authors: Chen PY, Qin L, Tellides G, Simons M Tags: Sci Signal Source Type: research

Response to comment on "Controlling long-term signaling: Receptor dynamics determine attenuation and refractory behavior of the TGF-β pathway"-Smad2/3 activity does not predict the dynamics of transcription.
Abstract Using an integrative experimental and computational modeling approach to dissect the signaling dynamics of the transforming growth factor-β to Smad (TGF-β/Smad) pathway, we discovered that previous exposure to ligand desensitizes cells, rendering them refractory to further acute TGF-β stimulation. We demonstrated that this refractory behavior, which also explains signal attenuation, is caused by the fast depletion from the cell surface of signaling-competent receptors upon TGF-β binding and their slow replenishment, which is the rate-limiting step for regaining full competence for acute ligand inductio...
Source: Science Signaling - September 27, 2014 Category: Biomedical Science Authors: Vizán P, J Miller DS, Schmierer B, Hill CS Tags: Sci Signal Source Type: research

Comment on "Controlling long-term signaling: Receptor dynamics determine attenuation and refractory behavior of the TGF-β pathway"-Smad2/3 activity does not predict the dynamics of transcription.
Abstract The transforming growth factor-β (TGF-β) pathway plays a fundamental role in development and disease. Despite its importance, the dynamics of signaling activity downstream of ligand stimulation have remained largely unexplored. The recent study by Vizán et al. demonstrates that loss of signaling-capable receptors from the cell surface leads to a refractory period during which cells are incapable of responding to additional signals. In this letter and in our previous work, we show that although receptor dynamics determine Smad2/3 activity, signaling activity at the level of transcription terminates far e...
Source: Science Signaling - September 27, 2014 Category: Biomedical Science Authors: Warmflash A, Zhang Q, Brivanlou AH, Siggia ED Tags: Sci Signal Source Type: research

Primary cutaneous Cryptococcus neoformans serotype D presenting as painful ulcer and nodules on elbow of an immunocompetent patient
(Source: Irish Journal of Medical Science)
Source: Irish Journal of Medical Science - September 27, 2014 Category: Journals (General) Source Type: research

Excessive daytime sleepiness and metabolic syndrome: a cross-sectional study
Excessive daytime sleepiness (EDS) has been associated with singular independent symptoms of metabolic syndrome, such as insulin resistance and diabetes. The aim of this study was to assess whether this relationship is sustained among individuals who meet criteria for the whole syndrome. (Source: Metabolism - Clinical and Experimental)
Source: Metabolism - Clinical and Experimental - September 27, 2014 Category: Biomedical Science Authors: Amie C. Hayley, Lana J. Williams, Gerard A. Kennedy, Michael Berk, Sharon L. Brennan, Julie A. Pasco Source Type: research

2nd International WALED Congress (World Academy for Laser Education in Dentistry) for graduates and alumni of Master of Science (M.Sc.) and Mastership / Fellowship programs of RWTH Aachen University in the field of lasers in dentistry
(Source: Lasers in Medical Science)
Source: Lasers in Medical Science - September 26, 2014 Category: Laser Surgery Source Type: research

Antibodies for immunolabeling by light and electron microscopy: not for the faint hearted
Abstract Reliable antibodies represent crucial tools in the arsenal of the cell biologist and using them to localize antigens for immunocytochemistry is one of their most important applications. However, antibody–antigen interactions are much more complex and unpredictable than suggested by the old ‘lock and key’ analogy, and the goal of trying to prove that an antibody is specific is far more difficult than is generally appreciated. Here, we discuss the problems associated with the very complicated issue of trying to establish that an antibody (and the results obtained with it) is specific for the immu...
Source: Histochemistry and Cell Biology - September 26, 2014 Category: Biomedical Science Source Type: research

High-fat diet alters the oligosaccharide chains of colon mucins in mice
In conclusion, our findings confirm that a fatty-rich diet (Western-style diet) induces alteration of mucins and may be associated with colon diseases. Our investigation corroborates the usefulness of lectins histochemistry in the early diagnosis of prepathological states of the colon. (Source: Histochemistry and Cell Biology)
Source: Histochemistry and Cell Biology - September 26, 2014 Category: Biomedical Science Source Type: research

Expression pattern of estrogen receptors α and β and G-protein-coupled estrogen receptor 1 in the human testis
Abstract Estrogen signaling is considered to play an important role in spermatogenesis, spermiogenesis and male fertility. Estrogens can act via the two nuclear estrogen receptors ESR1 (ERα) and ESR2 (ERβ) or via the intracellular G-protein-coupled estrogen receptor 1 (GPER, formerly GPR30). Several reports on the localization and expression of all three receptors in the human testis have been published but are controversial particularly in case of ERα. Contrary to previous studies, we decided therefore to evaluate expression of all three receptors in the testis by a number of different methods and in comparis...
Source: Histochemistry and Cell Biology - September 26, 2014 Category: Biomedical Science Source Type: research

Sensory innervation of the dorsal longitudinal ligament and the meninges in the lumbar spine of the dog
Abstract Although intervertebral disc herniation is a well-known disease in dogs, pain management for this condition has remained a challenge. The goal of the present study is to address the lack of information regarding the innervation of anatomical structures within the canine vertebral canal. Immunolabeling was performed with antibodies against protein gene product 9.5, Tuj-1 (neuron-specific class III β-tubulin), calcitonin gene-related peptide, and neuropeptide Y in combination with the lectin from Lycopersicon esculentum as a marker for blood vessels. Staining was indicative of both sensory and sympathetic...
Source: Histochemistry and Cell Biology - September 26, 2014 Category: Biomedical Science Source Type: research

Human osteoarthritic knee cartilage: fingerprinting of adhesion/growth-regulatory galectins in vitro and in situ indicates differential upregulation in severe degeneration
Abstract The apparent connection of galectin-3 to chondrocyte survival and osteoarthritis-like cartilage modifications in animal models provided incentive for the mapping of seven members of this family of adhesion/growth-regulatory proteins in human cartilage specimens. Starting with work in vitro, RT-qPCR analyses and immunocytochemistry revealed gene transcription and protein presence in cultured OA chondrocytes, especially for galectin-1, galectin-3 and galectin-8. Immunohistochemistry in clinical specimens with mild and severe cartilage degeneration detected galectins in chondrocytes—with upregulation, esp...
Source: Histochemistry and Cell Biology - September 26, 2014 Category: Biomedical Science Source Type: research

IL-7 splicing variant IL-7δ5 induces EMT and metastasis of human breast cancer cell lines MCF-7 and BT-20 through activation of PI3K/Akt pathway
In conclusion, our findings demonstrate that IL-7δ5 induces human breast cancer cell lines EMT and metastasis via activation of PI3K/Akt pathway. Thus, IL-7δ5 may be a potential target against human breast cancer. (Source: Histochemistry and Cell Biology)
Source: Histochemistry and Cell Biology - September 26, 2014 Category: Biomedical Science Source Type: research

A rapid ex vivo tissue model for optimising drug detection and ionisation in MALDI imaging studies
Abstract The aim of this study was to establish an ex vivo model for a faster optimisation of sample preparation procedures, for example matrix choice, in matrix-assisted laser desorption/ionisation (MALDI) drug imaging studies. The ionisation properties of four drugs, afatinib, erlotinib, irinotecan and pirfenidone, were determined in an ex vivo tissue experiment by spotting decreasing dilution series onto liver sections. Hereby, the drug signals were distinctly detectable using different matrix compounds, which allowed the selection of the optimal matrix for each drug. The analysis of afatinib and erlotinib yie...
Source: Histochemistry and Cell Biology - September 26, 2014 Category: Biomedical Science Source Type: research

Phosphatase and actin regulator 4 is associated with intermediate filaments in adult neural stem cells and their progenitor astrocytes
Abstract Phosphatase and actin regulator 4 (Phactr4) is a newly discovered protein that inhibits protein phosphatase 1 and shows actin-binding activity. We previously found that Phactr4 is expressed in the neurogenic niche in adult mice, although its precise subcellular localization and possible function in neural stem cells (NSCs) is not yet understood. Here, we show that Phactr4 formed punctiform clusters in the cytosol of subventricular zone-derived adult NSCs and their progeny in vitro. These Phactr4 signals were not associated with F-actin fibers but were closely associated with intermediate filaments such a...
Source: Histochemistry and Cell Biology - September 26, 2014 Category: Biomedical Science Source Type: research

Inhibition of JNK in HaCaT cells induced tight junction formation with decreased expression of cytokeratin 5, cytokeratin 17 and desmoglein 3
Abstract Epidermal keratinocytes proliferate in the basal layer, differentiate, migrate through the spinous layer, granular layer and cornified layer, and finally are peeled off from the surface of skin with layer-specific expression of differentiation markers, including cytokeratins and cell–cell junction proteins such as desmogleins. Basal cells express CK5, CK14 and Ki67. In contrast, the suprabasal cells in the spinous and granular layers express CK1 and CK10 without Ki67. Inhibition of c-Jun NH2-terminal protein kinase (JNK) in HaCaT cells, a human epidermal keratinocyte cell line, induced the formation of...
Source: Histochemistry and Cell Biology - September 26, 2014 Category: Biomedical Science Source Type: research

In vitro characterization of self-assembled anterior cruciate ligament cell spheroids for ligament tissue engineering
Abstract Tissue engineering of an anterior cruciate ligament (ACL) implant with functional enthesis requires site-directed seeding of different cell types on the same scaffold. Therefore, we studied the suitability of self-assembled three-dimensional spheroids generated by lapine ACL ligament fibroblasts for directed scaffold colonization. The spheroids were characterized in vitro during 14 days in static and 7 days in dynamic culture. Size maintenance of self-assembled spheroids, the vitality, the morphology and the expression pattern of the cells were monitored. Additionally, we analyzed the total sulfated gly...
Source: Histochemistry and Cell Biology - September 26, 2014 Category: Biomedical Science Source Type: research

Low-level laser therapy for orthodontic pain: a systematic review
Abstract This review aimed to evaluate the clinical outcome of different lasers management on orthodontic pain. Cochrane Library (Issue 7, 2014) and MEDLINE (1966–2014.7) were searched to collect randomized controlled trials on lasers for orthodontic pain. Studies meeting the inclusion criteria were systematically evaluated. The Cochrane Collaboration tools RevMan5.1.7 and GRADEpro 3.6 were used in this systematic review and meta-analysis. As a result, 11 randomized controlled trials (RCTs) studying on low-level laser therapy (LLLT) for orthodontic pain control were included. Meta-analysis and risk of bias asses...
Source: Lasers in Medical Science - September 26, 2014 Category: Laser Surgery Source Type: research

Modeling of plant in vitro cultures: Overview and estimation of biotechnological processes
ABSTRACT Plant cell and tissue cultivations are of growing interest for the production of structurally complex and expensive plant‐derived products, especially in pharmaceutical production. Problems with up‐scaling, low yields, and high‐priced process conditions result in an increased demand for models to provide comprehension, simulation, and optimization of production processes. In the last 25 years, many models have evolved in plant biotechnology; the majority of them are specialized models for a few selected products or nutritional conditions. In this article we review, delineate, and discuss the concepts and cha...
Source: Biotechnology and Bioengineering - September 26, 2014 Category: Biomedical Science Authors: Rüdiger W. Maschke, Katja Geipel, Thomas Bley Tags: Review Source Type: research

Protein-ligand structure guided by backbone and side-chain proton chemical shift perturbations.
Abstract The fragment-based drug design approach consists of screening libraries of fragment-like ligands, to identify hits that typically bind the protein target with weak affinity ([Formula: see text]-5 mM). The determination of the protein-fragment complex 3D structure constitutes a crucial step for uncovering the key interactions responsible for the protein-ligand recognition, and for growing the initial fragment into potent active compounds. The vast majority of fragments are aromatic compounds that induce chemical shift perturbations (CSP) on protein NMR spectra. These experimental CSPs can be quantitatively...
Source: Journal of Bimolecular NMR - September 26, 2014 Category: Biomedical Science Authors: Aguirre C, Ten Brink T, Cala O, Guichou JF, Krimm I Tags: J Biomol NMR Source Type: research

Structure, production and signaling of leptin
The cloning of leptin in 1994 was an important milestone in obesity research. In those days obesity was stigmatized as a condition caused by lack of character and self-control. Mutations in either leptin or its receptor were the first single gene mutations found to cause morbid obesity, and it is now appreciated that obesity is caused by a dysregulation of central neuronal circuits. From the first discovery of the leptin deficient obese mouse (ob/ob), to the cloning of leptin (ob aka lep) and leptin receptor (db aka lepr) genes, much has been learned about leptin and its action in the central nervous system. (Source: Metab...
Source: Metabolism - Clinical and Experimental - September 26, 2014 Category: Biomedical Science Authors: Heike Münzberg, Christopher D. Morrison Tags: Review Source Type: research

Comparison of bolus injection and constant infusion methods for measuring muscle protein fractional synthesis rate in humans
In this study, we compared calf (gastrocnemius) muscle protein FSR measured using these two different methods — CI and BI. (Source: Metabolism - Clinical and Experimental)
Source: Metabolism - Clinical and Experimental - September 26, 2014 Category: Biomedical Science Authors: Demidmaa Tuvdendorj, David L. Chinkes, John Bahadorani, Xiao-jun Zhang, Melinda Sheffield-Moore, Lois A. Killewich, Robert R. Wolfe Source Type: research

Risk of diabetes in patients treated with HMG-CoA reductase inhibitors
3-Hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors (statins) are used to control blood cholesterol levels and reduce cardiovascular disease. It has been repeatedly reported that statins may cause new-onset diabetes mellitus (DM). However, limited evidence exists from direct head to head comparisons of statins on whether the risk of DM differs among statins. We investigated the risk of development of new-onset diabetes in subjects treated with different statins. (Source: Metabolism - Clinical and Experimental)
Source: Metabolism - Clinical and Experimental - September 26, 2014 Category: Biomedical Science Authors: Yongin Cho, EunYeong Choe, Yong-ho Lee, Ji Won Seo, Younjeong Choi, Yujung Yun, Hye Jin Wang, Chul Woo Ahn, Bong Soo Cha, Hyun Chul Lee, Eun Seok Kang Source Type: research

Increased glycemic variability and decrease of the postprandial glucose contribution to HbA1c in obese subjects across the glycemic continuum from normal glycemia to first time diagnosed diabetes
This study aimed at examining, in a series of overweight/obese patients without known glycemic disorder, the contribution of PPG to a “relative” hyperglycemia (glucose values ≥5.5mmol/L) and the presence of glycemic variability according to HbA1c levels. (Source: Metabolism - Clinical and Experimental)
Source: Metabolism - Clinical and Experimental - September 26, 2014 Category: Biomedical Science Authors: Marinos Fysekidis, Emmanuel Cosson, Isabela Banu, Régine Duteil, Chantal Cyrille, Paul Valensi Source Type: research

Modulation of neuroimmunity by adenosine and its receptors: Metabolism to mental illness
Adenosine is a pleiotropic bioactive with potent neuromodulatory properties. Due to its ability to easily cross the blood–brain barrier, it can act as a signaling molecule between the periphery and the brain. It functions through four (A1, A2A, A2B, and A3) cell surface G protein-coupled adenosine receptors (ARs) that are expressed in some combination on nearly all cells types within the CNS. By regulating the activity of adenylyl cyclase and changing the intracellular concentration of cAMP, adenosine can alter neuronal function and neurotransmission. (Source: Metabolism - Clinical and Experimental)
Source: Metabolism - Clinical and Experimental - September 26, 2014 Category: Biomedical Science Authors: Gabriel S. Chiu, Gregory G. Freund Source Type: research

Electrophysiology
(Source: Irish Journal of Medical Science)
Source: Irish Journal of Medical Science - September 25, 2014 Category: Journals (General) Source Type: research

The top 50 science stars of Twitter according to AAAS/Science. What does it mean?
It's nice to be on the list of The top 50 science stars of Twitter according to AAAS/Science. However, the list is based on somewhat arbitrary criteria and is meant to provoke discussion rather than to be taken seriously. What is valuable, however, are some of the quotes by scientists interviewed for the story. A selection of the quotes is posted below. The skeptic view on TwitterFact of life: Most high-performing scientists have not embraced Twitter. Why? "Highest ranking chemist considers Twitter a waste of time that he’d much prefer spending on reading, writing papers".Twitter proponents win this argumentHowever, this...
Source: Clinical Cases and Images - September 25, 2014 Category: Journals (General) Tags: Twitter Source Type: news

X‐ray phase contrast imaging of calcified tissue and biomaterial structure in bioreactor engineered tissues
Abstract Tissues engineered in bioreactor systems have been used clinically to replace damaged tissues and organs. In addition, these systems are under continued development for many tissue engineering applications. The ability to quantitatively assess material structure and tissue formation is critical for evaluating bioreactor efficacy and for pre‐implantation assessment of tissue quality. Techniques that allow for the non‐destructive and longitudinal monitoring of large engineered tissues within the bioreactor systems will be essential for the translation of these strategies to viable clinical therapies. X‐ray Pha...
Source: Biotechnology and Bioengineering - September 25, 2014 Category: Biomedical Science Authors: Alyssa A. Appel, Jeffery C. Larson, Alfred B. Garson, Huifeng Guan, Zhong Zhong, Bao‐Ngoc B. Nguyen, John Fisher, Mark A. Anastasio, Eric M. Brey Tags: Tissue Engineering and Delivery Systems Source Type: research

Amplified Chemiluminescence Detection of DNA by Strand-Displacement Polymerization Target Recycling and G-quadruplexes/Hemin DNAzyme Catalysis
Abstract A new strategy based on strand-displacement polymerization target recycling and G-quadruplex DNAzyme catalysis was developed for amplified chemiluminescence detection of DNA. The amplified detection was achieved by using the system consisted of hairpin DNA probe, G-rich DNA, primer, and polymerase Klenow fragment exo−. When the target DNA was introduced the system, the hairpin structure of DNA probe was opened by the hybridizing of target DNA with its complementary sequence, the primer hybridized then with DNA probe and initiated polymerase-aided strand-displacement polymerization reaction, resulting i...
Source: Plasmonics - September 25, 2014 Category: Biomedical Science Source Type: research

Generation of Multiple Fano Resonances in Plasmonic Split Nanoring Dimer
We present a computational study of the plasmonic response of a split nanoring dimer resonator which supports multiple plasmonic Fano-like resonances that arises by the coupling and interference of the dimer plasmon modes. For the generation of Fano resonances with large modulation depths, numerous configurations of the dimer resonator are analyzed which are observed to be highly dependent on the polarization of incident light. Moreover, the influence of dimension of the split nanoring structure on the spectral positions and intensities of the higher order Fano resonances are also investigated, and it is found that the asy...
Source: Plasmonics - September 25, 2014 Category: Biomedical Science Source Type: research

On the Performance of Highly Sensitive and Accurate Graphene-on-Aluminum and Silicon-Based SPR Biosensor for Visible and Near Infrared
Abstract We demonstrate the numerical analysis of surface plasmon resonance biosensor based on graphene on aluminum and silicon. Employing matrix method, it is found that the proposed sensor exhibits high imaging sensitivity ∼400 RIU−1 to 550 RIU−1 in a large dynamic range from visible to near IR region. It is observed that the application of monolayer or bilayer graphene over aluminum not only protects it from oxidation but also enhances the adsorption of biomolecules, which results in the detection of large refractive indices ranging from aqueous solution to biomolecules (refractive index 1.330 to 1.480) ...
Source: Plasmonics - September 25, 2014 Category: Biomedical Science Source Type: research

Modification of a Silver Substrate for Advanced Spectro-Electrochemical Applications of SERR Spectroscopy
Abstract A substrate for surface-enhanced resonance Raman spectroscopy (SERRS) in the near-ultraviolet (UV) range is presented, extending the potential window for electrochemical applications. Silver nanoparticles were synthesized exhibiting a localized surface plasmon resonance at the excitation wavelength and adsorbed onto a template-stripped silver substrate, whereby the number of particles per unit area was controlled by the adsorption time. Any attempt to employ spectro-electrochemistry on these surfaces, however, was hampered by the anodic dissolution of silver at potentials higher than 300 mV vs. standard...
Source: Plasmonics - September 25, 2014 Category: Biomedical Science Source Type: research

Adaptive Neuro-Fuzzy Appraisal of Plasmonic Studies on Morphology of Deposited Silver Thin Films Having Different Thicknesses
Abstract This work presents an experimental analysis on the tunable localized surface plasmon resonance (LSPR), obtained from deposited silver (Ag) thin films of various thicknesses. Silver thin films are prepared using electron beam deposition and undergo an annealing process at different temperatures to produce distinctive sizes of Ag metal nanoparticles (MNPs). The variability of structure sizes and shapes provides an effective means of tuning the position of the LSPR within a wide wavelength range. This paper provides an estimation of LSPR over a broad wavelength range by a process in which the resonance spec...
Source: Plasmonics - September 25, 2014 Category: Biomedical Science Source Type: research

Ultracompact Slow Surface Plasmon Polaritons Superlattice with Broad Bandwidth and Super-High Normalized Delay-Bandwidth Product
Abstract In this paper, we propose an ultracompact low-loss plasmonic superlattice for slow surface plasmon polaritons. The superlattice consists of a two-dimensional metal gap waveguide (Ag-SiO2-Ag) inserted with thin metal films working as coupled reflectors. Theoretical calculations indicate that the device is working on a broad bandwidth of 37 THz including the two telecom wavelengths of 1,310 and 1,550 nm and with mean group refractive index of 3.5 and mean transmission of 60 %. As the total geometric thickness is only 1.6 μm, the normalized delay-bandwidth product of the superlattice is as high as 0.44...
Source: Plasmonics - September 25, 2014 Category: Biomedical Science Source Type: research

Complicated Wavefront Shaping of Surface Plasmon Polaritons on Metal Surface by Holographic Groove Patterns
Abstract Surface plasmon polaritons (SPPs) manipulation on metal surfaces is important for constructing ultracompact integrated micro/nano-optical devices and systems. We employ the methodology of surface electromagnetic wave holography (SWH) to design holographic groove patterns for controlling SPPs with complicated wavefronts traveling on metal surface. SPPs are scattered by these deli groove patterns and interfere with each other to form desired SPP wavefronts. Several devices are demonstrated to control the intensities and phases of SPPs, such as focusing a plane SPP or diverging SPPs to two points with diffe...
Source: Plasmonics - September 25, 2014 Category: Biomedical Science Source Type: research

Ag and Sn Nanoparticles to Enhance the Near-Infrared Absorbance of a-Si:H Thin Films
Abstract Silver (Ag) and tin (Sn) nanoparticles (NPs) were deposited by thermal evaporation onto heated glass substrates with a good control of size, shape and surface coverage. This process has the advantage of allowing the fabrication of thin-film solar cells with incorporated NPs without vacuum break, since it does not require chemical processes or post-deposition annealing. The X-ray diffraction, TEM and SEM properties are correlated with optical measurements and amorphous silicon hydrogenated (a-Si:H) films deposited on top of both types of NPs show enhanced absorbance in the near-infrared. The results are i...
Source: Plasmonics - September 25, 2014 Category: Biomedical Science Source Type: research

Characterization of Grating Coupled Surface Plasmon Polaritons Using Diffracted Rays Transmittance
Abstract A method to sense the excitation of surface plasmon polariton (SPP) on metallic grating device using the transmitted signal will be presented. The grating transmittance signal will be fully characterized varying the light incident angle and azimuthal grating orientation by means of the SPP vector model and rigorous coupled-wave analysis simulation. Simulation results will be compared with experimental measurements obtained with a 635 nm wavelength laser in the transverse magnetic polarization mode. The laser will light grating devices in contact with either air or water through a customized microfluidic...
Source: Plasmonics - September 25, 2014 Category: Biomedical Science Source Type: research

Localized Surface Plasmon Enhanced Organic Light-Emitting Diodes
Abstract Current work demonstrates enhanced efficiencies in organic light-emitting diodes by using the localized surface plasmons originated from Au nanoclusters deposited using thermal evaporation technique. The effect of localized surface plasmons on organic emitter was studied using UV–vis absorption spectra, steady state and time-resolved photoluminescence spectra. These studies have revealed that the optical properties like absorption, emission have been greatly modified by the localized surface plasmon. These effects were found to be dependent on the distance between the emitter and Au layer. Further, eff...
Source: Plasmonics - September 25, 2014 Category: Biomedical Science Source Type: research

Tunable Nonreciprocal Tunneling Based on Nonsymmetric Magnetoplasmonic Resonance Structure
Abstract In order to achieve nonreciprocal transmission, we design an optical system composed of a sandwiched structure (magneto-optical media/metal/magneto-optical media) and a pair of coupling prisms. Using the developed transfer matrix method for magnetic materials, we study the transmission properties of the system in detail. The unusual result is that a tunable nonreciprocal resonance tunneling can be achieved through a nonsymmetric configuration of the system. The nonreciprocal resonance tunneling results from the nonsymmetric coupling of magnetoplasmonic coupled resonances. The results are verified through...
Source: Plasmonics - September 25, 2014 Category: Biomedical Science Source Type: research

InGaN/GaN MQW Photoluminescence Enhancement by Localized Surface Plasmon Resonance on Isolated Ag Nanoparticles
Abstract Spectroscopic study of photoluminescence (PL) enhancement due to the coupling of the light emitters in InGaN/GaN multiple quantum wells (MQWs) with the localized surface plasmon (LSP) resonance on silver (Ag) nanoparticles (NPs) is performed using the confocal microscopy and scanning near-field optical microscopy (SNOM) techniques. The paper is focused on revealing the emission enhancement due to coupling with a single metal nanoparticle. The enhancement is confirmed by time-resolved study of differential transmission (DT). The enhancement suppression caused by potential fluctuations due to the variation...
Source: Plasmonics - September 25, 2014 Category: Biomedical Science Source Type: research

Effect of Interparticle Field Enhancement in Self-Assembled Silver Aggregates on Surface-Enhanced Raman Scattering
Abstract The presence of so-called hot spots, regions with strongly enhanced electromagnetic field, is a critical property of a substrate enabling detection of surface-enhanced Raman scattering (SERS) signals at high enhancement levels. In this work, the effect of interparticle field enhancement on SERS signals was investigated comparing SERS spectra of ethylenediaminetetraacetic-disodium salt in the chemically produced colloids with isolated and aggregated silver nanoparticles using 473 and 532-nm wavelength excitation. The presence of aggregates in the colloidal solution resulted in SERS spectra that were insen...
Source: Plasmonics - September 25, 2014 Category: Biomedical Science Source Type: research

Tunable Extraordinary THz Transmission Using Liquid Metal-Based Devices
Abstract In this paper, we report novel designs of tunable THz plasmonic devices based on liquid metals. The designed devices will be able to dynamically control and change the spectrum responses of extraordinary THz wave transmissions. Different THz device configurations are investigated, and numerical simulations have been conducted to theoretically verify the performance of the proposed structures. Moreover, an equivalent circuit model has been developed to describe the operating principle of the proposed THz devices. Good agreement has been achieved between the theoretical models and the numerical results. Th...
Source: Plasmonics - September 25, 2014 Category: Biomedical Science Source Type: research