MedWorm provides a medical RSS filtering service. Over 6000 RSS medical sources are combined and output via different filters. This feed contains the latest medical blog items that have been tagged with 'assay'. Sat, 03 Sep 2011 02:24:58 +0100 http://www.medworm.com/index.php?rid=5158895&cid=t_287798_87_f&fid=34902&url=http%3A%2F%2Fwww.futurepundit.com%2Farchives%2F008247.html Direct-to-consumer genetic testing company 23andMe used customer data and volunteered health information from customers to confirm over 180 known genetic associations with diseases and human characteristics. As the number of people who have gotten themselves genetically tested goes up by orders of magnitude so too will the ability of genetic testing services provides to find more associations between genes and assorted diseases and attributes of humans. MOUNTAIN VIEW, CA – (August 17, 2011) – 23andMe, Inc., a leading personal genetics company has replicated over 180 genetic associations from a list of associations curated by the National Human Genome Research Institute’s Office of Population Genomics ("GWAS Catalog") demonstrating that self-reported medical data is effective and reliabl... FuturePundit blogs http://www.medworm.com/rss/comments.php?id=5158895 Thu, 18 Aug 2011 23:00:00 +0100 5158895 http://www.medworm.com/index.php?rid=5086124&cid=t_287798_87_f&fid=34902&url=http%3A%2F%2Fwww.futurepundit.com%2Farchives%2F008212.html Of course it will work in a suburban tract home too. New York, NY—July 31, 2011—Samuel K. Sia, assistant professor of biomedical engineering at Columbia Engineering, has developed an innovative strategy for an integrated microfluidic-based diagnostic device—in effect, a lab-on-a-chip—that can perform complex laboratory assays, and do so with such simplicity that these tests can be carried out in the most remote regions of the world. In a paper published in Nature Medicine online on July 31, Sia presents the first published field results on how microfluidics—the manipulation of small amounts of fluids—and nanoparticles can be successfully leveraged to produce a functional low-cost diagnostic device in extreme resource-limited settings. Sia and his team performed testing in Rwanda over... FuturePundit blogs http://www.medworm.com/rss/comments.php?id=5086124 Sun, 31 Jul 2011 23:00:00 +0100 5086124 http://www.medworm.com/index.php?rid=5050470&cid=t_287798_87_f&fid=34902&url=http%3A%2F%2Fwww.futurepundit.com%2Farchives%2F008192.html A fluorescent dye injected into the skin will change its fluorescence based on concentrations of a target chemical in the blood (e.g. sodium or sugar) and then a smart phone add-on can read the dye to measure blood levels of a the chemical of interest. Using a nanosensor "tattoo" and a modified iPhone, cyclists could closely monitor sodium levels to prevent dehydration, and anemic patients could track their blood oxygen levels. Heather Clark, a professor in the Department of Pharmaceutical Sciences at Northeastern University, is leading a team working to make this possible. The team begins by injecting a solution containing carefully chosen nanoparticles into the skin. You can imagine a series of small bars of dyes added to the... (Source: FuturePundit) FuturePundit blogs http://www.medworm.com/rss/comments.php?id=5050470 Thu, 21 Jul 2011 23:00:00 +0100 5050470 http://www.medworm.com/index.php?rid=4622213&cid=t_287798_87_f&fid=34902&url=http%3A%2F%2Fwww.futurepundit.com%2Farchives%2F007980.html The field of microfluidics holds the promise of orders of magnitude cheaper biological assays of blood and other samples. Plus, it will enable fast testing without sending off to a lab. Well, an international group of researchers has developed an autonomous lab-on-a-chip. BERKELEY — A major milestone in microfluidics could soon lead to stand-alone, self-powered chips that can diagnose diseases within minutes. The device, developed by an international team of researchers from the University of California, Berkeley, Dublin City University in Ireland and Universidad de Valparaíso Chile, is able to process whole blood samples without the use of external tubing and extra components. The researchers have dubbed the device SIMBAS, which stands for Self-powered Integrated Microfluidic Blood Anal... FuturePundit blogs http://www.medworm.com/rss/comments.php?id=4622213 Tue, 22 Mar 2011 00:00:00 +0100 4622213 http://www.medworm.com/index.php?rid=4450257&cid=t_287798_87_f&fid=34902&url=http%3A%2F%2Fwww.futurepundit.com%2Farchives%2F007884.html A female black lab named "Marine" who excelled at using her nose to detect bowel cancer is not alone. A Belgian Malinois in Paris shows a knack for detecting prostate cancer by sniffing urine. Given that dogs are going to sniff urine anyway might as well as make this instinctive desire useful. Arnhem, The Netherlands, 7 February 2011 -- In the February 2011 issue of European Urology, Jean-Nicolas Cornu and colleagues reported the evaluation of the efficacy of prostate cancer (PCa) detection by trained dogs on human urine samples. A reminder on why this matters: Dogs show the potential to detect cancers at earlier stages. If cancer can be caught before metastasis then the odds of death go way down.... (Source: FuturePundit) FuturePundit blogs http://www.medworm.com/rss/comments.php?id=4450257 Sun, 06 Feb 2011 00:00:00 +0100 4450257 http://www.medworm.com/index.php?rid=4424205&cid=t_287798_87_f&fid=34902&url=http%3A%2F%2Fwww.futurepundit.com%2Farchives%2F007861.html Have you gone too long since you last saw a dog for a check-up? Don't worry, he'll still be happy to see you. A specially trained Labrador retriever completed 74 sniff tests, each comprising five breath (100 to 200 ml) or stool samples (50 ml) at a time, only one of which was cancerous, over a period of several months. The samples came from 48 people with confirmed bowel cancer and 258 volunteers with no bowel cancer or who had had cancer in the past. Around half of the volunteer samples came from people with bowel polyps, which although benign, are considered to be a precursor of bowel cancer. And 6% of the breath samples and one in 10 of... (Source: FuturePundit) FuturePundit blogs http://www.medworm.com/rss/comments.php?id=4424205 Mon, 31 Jan 2011 00:00:00 +0100 4424205 http://www.medworm.com/index.php?rid=4405736&cid=t_287798_87_f&fid=34902&url=http%3A%2F%2Fwww.futurepundit.com%2Farchives%2F007856.html Paper strips will perform a wider variety of medical tests. WEST LAFAYETTE, Ind. - Researchers have invented a technique that uses inexpensive paper to make "microfluidic" devices for rapid medical diagnostics and chemical analysis. The innovation represents a way to enhance commercially available diagnostic devices that use paper-strip assays like those that test for diabetes and pregnancy. Advances that lower medical testing costs while also provide immediate results without a big lab will accelerate the trend direct-to-consumer medical testing. People will do medical testing at home and more frequently. They'll upload their test results to servers running medical expert systems that will provide diagnostic results and monitor your conditions. Paper test strips will do more complex chemi... FuturePundit blogs http://www.medworm.com/rss/comments.php?id=4405736 Thu, 27 Jan 2011 00:00:00 +0100 4405736 http://www.medworm.com/index.php?rid=4342737&cid=t_287798_139_f&fid=38879&url=http%3A%2F%2Ffeedproxy.google.com%2F%7Er%2FVirologyBlog%2F%7E3%2FuLm1tCudeRQ%2F (MOI) is a frequently used term in virology which refers to the number of virions that are added per cell during infection. If one million virions are added to one million cells, the MOI is one. If ten million virions are added, the MOI is ten. Add 100,000 virions, and the MOI is 0.1. The concept is straightforward. But here is the tricky part. If you infect cells at a MOI of one, does that mean that each cell in the cutlure receives one virion? The answer is no. Here is another way to look at this problem: imagine a room containing 100 buckets. If you threw 100 tennis balls into that room – all at the same time – would each bucket get one ball? Most likely not. How many tennis balls end up in each bucket, or the number of virions that each cell receives at different MOI, is d... virology blog blogs http://www.medworm.com/rss/comments.php?id=4342737 Thu, 13 Jan 2011 14:57:25 +0100 4342737 http://www.medworm.com/index.php?rid=4337884&cid=t_287798_87_f&fid=34902&url=http%3A%2F%2Fwww.futurepundit.com%2Farchives%2F007822.html This article has useful... (Source: FuturePundit) FuturePundit blogs http://www.medworm.com/rss/comments.php?id=4337884 Tue, 11 Jan 2011 00:00:00 +0100 4337884 http://www.medworm.com/index.php?rid=4330976&cid=t_287798_87_f&fid=34902&url=http%3A%2F%2Fwww.futurepundit.com%2Farchives%2F007817.html Microfluidic devices will eliminate the need to return to a doctor's office to get test results. The testing will be done while you wait. KINGSTON, R.I. – January 10, 2011 -- While most blood tests require shipping a vial of blood to a laboratory for analysis and waiting several days for the results, a new device invented by a team of engineers and students at the University of Rhode Island uses just a pinprick of blood in a portable device that provides results in less than 30 minutes. Microfluidic devices will enable point-of-care diagnostics. But they will also enable drug stores to offer a wide range of blood testing services at a lower cost, at more convenient locations, and over... (Source: FuturePundit) FuturePundit blogs http://www.medworm.com/rss/comments.php?id=4330976 Mon, 10 Jan 2011 00:00:00 +0100 4330976 http://www.medworm.com/index.php?rid=4313973&cid=t_287798_87_f&fid=34902&url=http%3A%2F%2Fwww.futurepundit.com%2Farchives%2F007801.html Smaller and cheaper. Dr. Rothberg is the founder of Ion Torrent, which last month began selling a sequencer it calls the Personal Genome Machine. While most sequencers cost hundreds of thousands of dollars and are at least the size of small refrigerators, this machine sells for just under $50,000 and is the size of a largish desktop printer. While not intended for the general public, the machine could expand the use of DNA sequencing from specialized centers to smaller university and industrial labs, and into hospitals and doctors’ offices, helping make DNA sequencing a standard part of medical practice. It is not as cheap as it sounds because it sequences only smaller genomes and consumes a $250 chip for each... (Source: FuturePundit) FuturePundit blogs http://www.medworm.com/rss/comments.php?id=4313973 Tue, 04 Jan 2011 00:00:00 +0100 4313973 http://www.medworm.com/index.php?rid=4275295&cid=t_287798_87_f&fid=34902&url=http%3A%2F%2Fwww.futurepundit.com%2Farchives%2F007765.html A small chip will some day sequence your entire genetic sequence in minutes. Of course, small and fast also means very cheap too. Scientists from Imperial College London are developing technology that could ultimately sequence a person’s genome in mere minutes, at a fraction of the cost of current commercial techniques. Couples on dates or sizing up each other in bars will some day surreptitiously take DNA samples of each other and do sequencing to find out of the romantic interest has desired attributes. How smart? How likely to be faithful? How driven? Genetic sequences will provide clues. The researchers have patented an early prototype technology that they believe could lead to an ultrafast commercial DNA sequencing tool within ten... (Source: FuturePundit) FuturePundit blogs http://www.medworm.com/rss/comments.php?id=4275295 Tue, 21 Dec 2010 00:00:00 +0100 4275295 http://www.medworm.com/index.php?rid=4214046&cid=t_287798_87_f&fid=34902&url=http%3A%2F%2Fwww.futurepundit.com%2Farchives%2F007709.html 20 years from now microfluidic chips will plug into our smart phones (or maybe into our virtual reality goggles). When we need to do a fast genetic test (either in a bar with a potential mate or at the pound when choosing a dog to adopt) pluggable microfluidic chips will come in handy. Biomedical engineers at UC Davis have developed a plug-in interface for the microfluidic chips that will form the basis of the next generation of compact medical devices. They hope that the "fit to flow" interface will become as ubiquitous as the USB interface for computer peripherals. UC Davis filed a provisional patent on the invention Nov. 1. A paper describing the devices was published online Nov. 25... (Source: FuturePundit) FuturePundit blogs http://www.medworm.com/rss/comments.php?id=4214046 Tue, 30 Nov 2010 00:00:00 +0100 4214046 http://www.medworm.com/index.php?rid=4200543&cid=t_287798_87_f&fid=34902&url=http%3A%2F%2Fwww.futurepundit.com%2Farchives%2F007681.html Razib Khan and Ray Sawhill both alerted me to a special personal DNA testing deal from 23andme.com for $99 plus $60 for a year of data analysis updates (where new research tells more about the half million DNA letters they test). Razib says to get the discount the discount codes are LOYALFAN, HHY6P4, GIZMODO99. 23andme does what is called SNP testing. SNP stands for single nucleotide polymorphism. Sounds fancy, right? Not really. SNPs are places in your 2.9 billion DNA letters where people differ from each other. The half million that 23andme test are so far known to be more interesting from a medical or genealogical standpoint than some millions of other known SNPs. So do they offer practical useful... (Source: FuturePundit) FuturePundit blogs http://www.medworm.com/rss/comments.php?id=4200543 Thu, 25 Nov 2010 00:00:00 +0100 4200543 http://www.medworm.com/index.php?rid=4027146&cid=t_287798_87_f&fid=34902&url=http%3A%2F%2Fwww.futurepundit.com%2Farchives%2F007539.html DENVER — Scientists may have discovered a way to diagnose bladder cancer at its earliest and, therefore, most treatable stages by measuring the presence or absence of microRNA using already available laboratory tests. They found these microRNA fingerprints for bladder cancer in blood, not urine. This suggests the same can be done for other cancers. If so, early stage cancer diagnosis for just about all cancers could some day be done with blood tests for patterns of microRNAs. To state the obvious: The earlier the diagnosis the easier a cancer is to cure. Get it before it metastasizes, remove it, and then avoid losing your hair, pucking up your guts, becoming extremely emaciated, and dying with cancer in your... (Source: FuturePundit) FuturePundit blogs http://www.medworm.com/rss/comments.php?id=4027146 Sun, 03 Oct 2010 23:00:00 +0100 4027146 http://www.medworm.com/index.php?rid=3880804&cid=t_287798_87_f&fid=34902&url=http%3A%2F%2Fwww.futurepundit.com%2Farchives%2F007419.html One breath alcohol analyzer company takes a critical look at its competition. DENVER – August 18, 2010 – Lifeloc Technologies, Inc., a leading manufacturer of professional breathalyzers has released the industry's first independent report on the accuracy and reliability of popular semiconductor (silicone oxide) breath testers sold in mass retail, pharmacy, specialty stores and on the Internet. "Anecdotal reports and experiences of consumers, law enforcement and other industry players have centered on the inaccuracy of semiconductor alcohol testers," said Barry Knott, president of Lifeloc. "New third party research has confirmed that popular semiconductor personal breathalyzers are notoriously inaccurate and should not be trusted for accurate BAC measurement. What we didn't know, until th... FuturePundit blogs http://www.medworm.com/rss/comments.php?id=3880804 Wed, 18 Aug 2010 23:00:00 +0100 3880804 http://www.medworm.com/index.php?rid=3858333&cid=t_287798_136_f&fid=37846&url=http%3A%2F%2Fhealthinfoispower.wordpress.com%2F2010%2F08%2F11%2Fgeorgia-techs-ovarian-cancer-early-detection-blood-test-exhibits-high-accuracy-in-small-study-larger-study-planned%2F Scientists at the Georgia Institute of Technology have attained very promising results on their initial investigations of a new test for ovarian cancer. Using a new technique involving mass spectrometry of a single drop of blood serum, the test correctly identified women with ovarian cancer in 100 percent of the 94 patients tested. Because of the extremely [...] (Source: Libby's H*O*P*E*) Libby's H*O*P*E* blogs http://www.medworm.com/rss/comments.php?id=3858333 Thu, 12 Aug 2010 02:50:07 +0100 3858333 http://www.medworm.com/index.php?rid=3633417&cid=t_287798_83_f&fid=34856&url=http%3A%2F%2Finsidesurgery.com%2F2010%2F06%2Fvon-willebrands-disease%2F Pathophysiology 1) type of bleeding disorder (can be inherited or acquired) due to a defect in, or reduction of, von Willebrand factor 2) four inherited forms exist – type I, type IIb, type IIN, and type III 3) type I – most common with mild to moderate symptoms; vWF is 50% decreased 4) types IIb and IIN – amount of vWF is near normal but activity is decreased 5) type III – defect in both amount and activity of vWF; a rare and severely hemorrhagic condition Signs and Symptoms 1) severity of symptoms is highly variable -from bleeding only after surgery or trauma to spontaneous 2) epistaxis 3) gastrointestinal bleeding 4) genitourinary tract bleeding 5) petechiae 6) ecchymosis 7) hemarthrosis Characteristic Test Findings Laboratory – 1) prolonged bleeding time ... Inside Surgery blogs http://www.medworm.com/rss/comments.php?id=3633417 Sun, 06 Jun 2010 06:59:32 +0100 3633417 http://www.medworm.com/index.php?rid=3424806&cid=t_287798_87_f&fid=34902&url=http%3A%2F%2Fwww.futurepundit.com%2Farchives%2F007063.html Having your blood sent to a lab for testing is so 20th century. In an office park in Woburn, MA, a volunteer presents his fingertip for a quick finger stick. A phlebotomist wicks up the small drop of blood with a specially made square of plastic, then snaps the plastic into a credit-card sized microfluidics cartridge and feeds it into a special reader. Fifteen minutes later, the device spits out the volunteer's prostate specific antigen (PSA) level, a protein used to monitor the return of prostate cancer after treatment. Microfluidics will move many lab tests to doctors' offices. The rapid results are possible because of a novel microfluidics technology developed by startup Claros Diagnostics, which hopes to make quick PSA... (Source: FuturePundit) FuturePundit blogs http://www.medworm.com/rss/comments.php?id=3424806 Mon, 29 Mar 2010 23:00:00 +0100 3424806 http://www.medworm.com/index.php?rid=3386874&cid=t_287798_87_f&fid=34902&url=http%3A%2F%2Fwww.futurepundit.com%2Farchives%2F007034.html Why make a second visit to your doctor to discuss test results when the tests can be completed during your first visit? In a joint project, researchers from seven Fraunhofer institutes have developed a modular platform for in vitro diagnosis which enables various types of bioanalysis – of blood and saliva for example – to be conducted in the doctor’s surgery. Thanks to its modular design our IVD platform is so flexible that it can be used for all possible bioanalytical tasks, states Dr. Eva Ehrentreich-Förster from the Fraunhofer Institute for Biomedical Engineering (IBMT) in Potsdam-Golm. The core element of the mini-laboratory is a disposable cartridge made of plastic which can be fitted with various types of sensor. For an... (Source: FuturePundit) FuturePundit blogs http://www.medworm.com/rss/comments.php?id=3386874 Sat, 20 Mar 2010 00:00:00 +0100 3386874 http://www.medworm.com/index.php?rid=3275766&cid=t_287798_87_f&fid=34902&url=http%3A%2F%2Fwww.futurepundit.com%2Farchives%2F006949.html The ultimate DNA sequencing devices will process individual strands of DNA, one letter at a time, thru measuring gates. Arizona State University researcher Stuart Lindsay leads a team using nanotech to read strands of DNA. Lindsay's team relies on the eyes of nanotechnology, scanning tunneling- (STM) and atomic force- (ATM) microscopes, to make their measurements. The microscopes have a delicate electrode tip that is held very close to the DNA sample. In their latest innovation, Lindsay's team made two electrodes, one on the end of microscope probe, and another on the surface, that had their tiny ends chemically modified to attract and catch the DNA between a gap like a pair of chemical tweezers. The gap between these functionalized electrodes... (Source: FuturePundit) FuturePundit blogs http://www.medworm.com/rss/comments.php?id=3275766 Mon, 15 Feb 2010 00:00:00 +0100 3275766 http://www.medworm.com/index.php?rid=3259189&cid=t_287798_136_f&fid=37846&url=http%3A%2F%2Fhealthinfoispower.wordpress.com%2F2010%2F02%2F09%2Fabbott-labs-seeks-fda-510k-clearance-for-new-automated-ovarian-cancer-detection-test%2F A new diagnostic tool physicians can use to monitor patients for the most common form of ovarian cancer may soon be available in the United States. A new diagnostic tool physicians can use to monitor patients for the most common form of ovarian cancer may soon be available in the United States.  Abbott Laboratories’ (Abbott’s) ARCHITECT [...] (Source: Libby's H*O*P*E*) Libby's H*O*P*E* blogs http://www.medworm.com/rss/comments.php?id=3259189 Tue, 09 Feb 2010 22:24:31 +0100 3259189 http://www.medworm.com/index.php?rid=3235515&cid=t_287798_139_f&fid=38879&url=http%3A%2F%2Ffeedproxy.google.com%2F%7Er%2FVirologyBlog%2F%7E3%2FeVxKn1VOhbM%2F One of the most important procedures in virology is measuring the virus titer – the concentration of viruses in a sample. A widely used approach for determining the quantity of infectious virus is the plaque assay. In this technique, the spread of progeny viruses released by individually infected cells is restricted to neighboring cells by a semisolid medium. Consequently, each infectious particle produces a circular zone of infected cells called a plaque. By imagining live, virus-infected cells using a microscope, beautiful movies have been made which show how a plaque develops in real time. To produce the movies, cells were infected with vaccinia virus, covered with a semi-solid medium, and placed in an incubator. The monolayers were examined periodically until a small plaque became vi... virology blog blogs http://www.medworm.com/rss/comments.php?id=3235515 Wed, 03 Feb 2010 11:59:48 +0100 3235515 http://www.medworm.com/index.php?rid=3236046&cid=t_287798_136_f&fid=36162&url=http%3A%2F%2Fwww.myelomablog.com%2F2010%2F02%2F02%2Fmyeloma-treatment-test-results%2F Here are my latest results. Specific Proteins Test Name Result AB Normal Range Units IGG 466 L 600-1700 MG/DL IGM 31 L 35-290 MG/DL IGA 408 H 40-400 MG/DL Electrophoresis The SPE pattern demonstrates two bands of restricted mobility in the gamma region. Immunofix, Serum Monoclonal component typed as IgA Lambda. Concentration of monoclonal protein determined by serum protein electrophoresis is 0.4 g/dL. Monoclonal component typed as IgA Lambda. Concentration of monoclonal protein determined by serum protein electrophoresis is 0.3 g/dL. *Suggestive of a monoclonal component typed as IgG Kappa. Concentration of monoclonal protein is too low to accurately quantify. * This is new! Previously, I’ve only ever had just two m-spikes. That’... beth's myeloma blog blogs http://www.medworm.com/rss/comments.php?id=3236046 Tue, 02 Feb 2010 20:43:21 +0100 3236046 http://www.medworm.com/index.php?rid=3139016&cid=t_287798_87_f&fid=34902&url=http%3A%2F%2Fwww.futurepundit.com%2Farchives%2F006840.html Carbon nanotubes can measure electrical fields of individual DNA letters. Faster sequencing of DNA holds enormous potential for biology and medicine, particularly for personalized diagnosis and customized treatment based on each individual's genomic makeup. At present however, sequencing technology remains cumbersome and cost prohibitive for most clinical applications, though this may be changing, thanks to a range of innovative new techniques. In the current issue of Science, Stuart Lindsay, director of Arizona State University's Center for Single Molecule Biophysics at the Biodesign Institute, along with his colleagues, demonstrates the potential of one such method in which a single-stranded ribbon of DNA is threaded through a carbon nanotube, producing voltage spikes that provide inform... FuturePundit blogs http://www.medworm.com/rss/comments.php?id=3139016 Sun, 03 Jan 2010 00:00:00 +0100 3139016 http://www.medworm.com/index.php?rid=3139015&cid=t_287798_87_f&fid=34902&url=http%3A%2F%2Fwww.futurepundit.com%2Farchives%2F006841.html Caveman DNA to reveal all. DNA that is left in the remains of long-dead plants, animals, or humans allows a direct look into the history of evolution. So far, studies of this kind on ancestral members of our own species have been hampered by scientists' inability to distinguish the ancient DNA from modern-day human DNA contamination. Now, research by Svante Pääbo from The Max-Planck Institute for Evolutionary Anthropology in Leipzig, published online on December 31st in Current Biology — a Cell Press publication — overcomes this hurdle and shows how it is possible to directly analyze DNA from a member of our own species who lived around 30,000 years ago. The ability to sequence individual DNA strands allows the scientists... (Source: FuturePundit) FuturePundit blogs http://www.medworm.com/rss/comments.php?id=3139015 Sun, 03 Jan 2010 00:00:00 +0100 3139015 http://www.medworm.com/index.php?rid=3096386&cid=t_287798_139_f&fid=38879&url=http%3A%2F%2Ffeedproxy.google.com%2F%7Er%2FVirologyBlog%2F%7E3%2Fka6DQ1O67f8%2F If you have been following the results of my experiments on inhibition of rhinovirus replication by ZnCl2, you know that I’ve been trying to determine why concentrations of the salt higher than 0.1 mM are toxic to HeLa cells. I have found that 0.1 mM ZnCl2 does inhibit rhinovirus plaque formation but not sufficiently to be able to select resistant mutants. In today’s set of experiments I asked whether the presence of MgCl2 in the agar overlay potentiates zinc toxicity. We always include MgCl2 (40 mM) in the agar overlay when assaying rhinoviruses, because it significantly improves plaque size. The following monolayers of HeLa cells were inoculated with 200 plaque-forming units of rhinovirus type 1a, then incubated at 32°C for 5 days. The effect of MgCl2 is remarkable. The use... virology blog blogs http://www.medworm.com/rss/comments.php?id=3096386 Wed, 16 Dec 2009 17:36:08 +0100 3096386 http://www.medworm.com/index.php?rid=3052107&cid=t_287798_87_f&fid=34902&url=http%3A%2F%2Fwww.futurepundit.com%2Farchives%2F006759.html A start-up is aiming a genetic testing machine at hospitals and doctors offices. A desktop instrument recently approved by the U.S. Food and Drug Administration might finally bring pharmacogenomic testing--the use of a patient's genetic information for drug prescription decisions--to the mainstream. The device, made by Nanosphere, a startup based in Northbrook, IL, can, in a matter of hours, detect genetic variations in blood that modulate the effectiveness of some drugs. Dubbed Verigene, the technology employs a combination of microfluidics and nanotechnology, housed in a single plastic cartridge, to pull DNA from a blood sample and then screen it for the relevant sequences. Microfluidics and nanotechnology moving into the marketplace. Genetic variations affect how we respond to drugs in ... FuturePundit blogs http://www.medworm.com/rss/comments.php?id=3052107 Thu, 03 Dec 2009 00:00:00 +0100 3052107 http://www.medworm.com/index.php?rid=3022729&cid=t_287798_139_f&fid=38879&url=http%3A%2F%2Ffeedproxy.google.com%2F%7Er%2FVirologyBlog%2F%7E3%2F1LdQplUyGXQ%2F Recently I began experiments to understand how zinc inhibits rhinovirus replication, and I promised to document my findings on the pages of this blog. Here are the results of the second plaque assay. In the last experiment I confirmed the finding that 0.1 mM ZnCl2 inhibits plaque formation by rhinovirus type 1A. Based on the results of that plaque assay, shown in the figure at left, I’ve decided that this concentration of zinc isn’t sufficient to completely inhibit viral replication. Although 0.1 mM ZnCl2 blocked plaque formation when 20 or 200 pfu were inoculated on cells, many plaques arose on plates inoculated with 2000 pfu. These cannot be viral mutants resistant to zinc – there are too many of them. If there are 2000 plaques on the untreated plate, and 200 on the pla... virology blog blogs http://www.medworm.com/rss/comments.php?id=3022729 Mon, 23 Nov 2009 17:27:58 +0100 3022729 http://www.medworm.com/index.php?rid=3016927&cid=t_287798_139_f&fid=38879&url=http%3A%2F%2Ffeedproxy.google.com%2F%7Er%2FVirologyBlog%2F%7E3%2F5meqJhkqthM%2F The title of this post should not come as a surprise to readers of virology blog – it was shown in 1974 that zinc could interfere with replication of rhinoviruses (see “Zinc and the common cold“). I am referring to the result of my first experiment to study the mechanism of zinc inhibition – something I promised I would document on these pages. I am interested in understanding how zinc inhibits rhinovirus replication. Answering this question could lead to new ways to prevent common colds caused by these viruses. The first step was to reproduce the effect of zinc in my laboratory with my stocks of rhinovirus. I selected rhinovirus type 1a for my initial experiments because we’ve worked with this serotype in the past: we know the genome sequence and how the viru... virology blog blogs http://www.medworm.com/rss/comments.php?id=3016927 Wed, 04 Nov 2009 15:35:42 +0100 3016927 http://www.medworm.com/index.php?rid=2782282&cid=t_287798_136_f&fid=35294&url=http%3A%2F%2Fwww.psa-rising.com%2Fblog%2F2009%2F09%2Fprostate-test-going-ahead-scientist-says%2F Dr. Robert Getzenberg, research director at Johns Hopkins Brady Urological Institute, said this morning that the EPCA-2 prostate cancer blood test is moving ahead and the law suit filed against him and the University of Pittsburgh is “for money.” “The science remains the same,” Getzenberg said about the progress of the EPCA-2 prostate cancer diagnositic [...] (Source: psa-rising.com/blog) psa-rising.com/blog blogs http://www.medworm.com/rss/comments.php?id=2782282 Thu, 10 Sep 2009 14:53:43 +0100 2782282 http://www.medworm.com/index.php?rid=2757703&cid=t_287798_87_f&fid=34902&url=http%3A%2F%2Fwww.futurepundit.com%2Farchives%2F006502.html Higher levels of volatile organic compounds in the breath serve as markers for lung cancer. Lung cancer is a brutal disease, often not caught until it's too late for treatment... (Source: FuturePundit) FuturePundit blogs http://www.medworm.com/rss/comments.php?id=2757703 Tue, 01 Sep 2009 23:00:00 +0100 2757703 http://www.medworm.com/index.php?rid=2741093&cid=t_287798_139_f&fid=38879&url=http%3A%2F%2Ffeedproxy.google.com%2F%7Er%2FVirologyBlog%2F%7E3%2FIYoK34TUQgw%2F The plaque assay is a terrific method for determining virus titers, but it doesn’t work for all viruses. Fortunately there are several alternative methods available, including the end-point dilution assay. The end-point dilution assay was used to measure virus titer before the development of the plaque assay, and is still used for viruses that do not form plaques. Serial dilutions of a virus stock are prepared and inoculated onto replicate cell cultures, often in multi-well formats (e.g. 96 well plastic plates). The number of cell cultures that are infected is then determined for each virus dilution, usually by looking for cytopathic effect. In this example of an end-point dilution assay, 10 monolayer cell cultures were infected with each virus dilution. After an incubation period, p... virology blog blogs http://www.medworm.com/rss/comments.php?id=2741093 Mon, 13 Jul 2009 13:00:40 +0100 2741093 http://www.medworm.com/index.php?rid=2741096&cid=t_287798_139_f&fid=38879&url=http%3A%2F%2Ffeedproxy.google.com%2F%7Er%2FVirologyBlog%2F%7E3%2FCe3400KRagc%2F The plaque assay is an essential tool for determining virus titers. The concept is simple: virus infection is restricted to neighboring cells by a semisolid overlay. By counting the number of plaques, the virus titer can be calculated in PFU per ml. A key question is: how many viruses are needed to form a single plaque? For most animal viruses, one infectious particle is sufficient to initiate infection. This conclusion can be reached by studying the relationship between the number of infectious virus particles and the plaque count. A linear relationship means that one infectious particle can form a plaque. In this case the virus is said to infect cells with one-hit kinetics. This concept is illustrated below. In this figure, the number of plaques produced by a virus with one-hit kinetics ... virology blog blogs http://www.medworm.com/rss/comments.php?id=2741096 Wed, 08 Jul 2009 13:00:57 +0100 2741096 http://www.medworm.com/index.php?rid=2741097&cid=t_287798_139_f&fid=38879&url=http%3A%2F%2Ffeedproxy.google.com%2F%7Er%2FVirologyBlog%2F%7E3%2FyTPmx8_-zog%2F One of the most important procedures in virology is measuring the virus titer – the concentration of viruses in a sample. A widely used approach for determining the quantity of infectious virus is the plaque assay. This technique was first developed to calculate the titers of bacteriophage stocks. Renato Dulbecco modified this procedure in 1952 for use in animal virology, and it has since been used for reliable determination of the titers of many different viruses. To perform a plaque assay, 10-fold dilutions of a virus stock are prepared, and 0.1 ml aliquots are inoculated onto susceptible cell monolayers. After an incubation period, to allow virus to attach to cells, the monolayers are covered with a nutrient medium containing a substance, usually agar, that causes the formation of... virology blog blogs http://www.medworm.com/rss/comments.php?id=2741097 Tue, 07 Jul 2009 03:32:18 +0100 2741097 http://www.medworm.com/index.php?rid=2097912&cid=t_287798_87_f&fid=34902&url=http%3A%2F%2Fwww.futurepundit.com%2Farchives%2F005871.html Noted Harvard psychologist and author Steven Pinker has an article in the New York Times Magazine entitled My Genome, My Self. He explores the relationship between your DNA sequence and... (Source: FuturePundit) FuturePundit blogs http://www.medworm.com/rss/comments.php?id=2097912 Sun, 11 Jan 2009 05:00:00 +0100 2097912 http://www.medworm.com/index.php?rid=1908779&cid=t_287798_87_f&fid=34902&url=http%3A%2F%2Fwww.futurepundit.com%2Farchives%2F005657.html Here's an example of scientific questions biologists can now ask due to advances in assaying tools. Scientists can watch the effects of a rhinovirus (one of the several families of... (Source: FuturePundit) FuturePundit blogs http://www.medworm.com/rss/comments.php?id=1908779 Mon, 27 Oct 2008 04:00:00 +0100 1908779 http://www.medworm.com/index.php?rid=1802932&cid=t_287798_150_f&fid=35777&url=http%3A%2F%2Ffeeds.feedburner.com%2F%7Er%2FPharmalot%2F%7E3%2F394542437%2F Where does a researcher turn when toxicology services are in short supply? In a new twist on the outsourcing craze, a new service hopes to fill that void with Assay Depot, an online marketplace that allows bench scientists to buy varying drug discovery services, according to Out-SourcingPharma. An example: a researcher looking for rodent toxicology services can log onto the site and find the relevant section listing various service providers, with prices and turnaround times. The user can also ask for quotes from Assay Depot’s registered providers, and either send samples directly to the provider, or make use of Assay Depot as an intermediary if anonymity is required, OutSourcing writes. The idea is to appeal to small drugmakers and biotechs, universities and virtual drug discovery firm... Pharmalot blogs http://www.medworm.com/rss/comments.php?id=1802932 Tue, 16 Sep 2008 20:31:45 +0100 1802932 http://www.medworm.com/index.php?rid=1770472&cid=t_287798_87_f&fid=34902&url=http%3A%2F%2Fwww.futurepundit.com%2Farchives%2F005516.html A group of researchers in Nanjing China have demonstrated that each type of cancer shows a unique fingerprint of types of microRNA in the blood. This opens up the possibility... (Source: FuturePundit) FuturePundit blogs http://www.medworm.com/rss/comments.php?id=1770472 Sat, 06 Sep 2008 04:00:00 +0100 1770472 http://www.medworm.com/index.php?rid=1664279&cid=t_287798_87_f&fid=34902&url=http%3A%2F%2Fwww.futurepundit.com%2Farchives%2F005399.html Smaller and cheaper is the future of biotechnology. PASADENA, Calif.--Researchers at the California Institute of Technology have turned science fiction into reality with their development of a super-compact high-resolution microscope,... (Source: FuturePundit) FuturePundit blogs http://www.medworm.com/rss/comments.php?id=1664279 Wed, 30 Jul 2008 04:00:00 +0100 1664279 http://www.medworm.com/index.php?rid=1358557&cid=t_287798_87_f&fid=34902&url=http%3A%2F%2Fwww.futurepundit.com%2Farchives%2F005122.html Up until now DNA sequencing has been done using many copies of each section of DNA. The older style sequencing machines do not have the sensitivity needed to measure the... (Source: FuturePundit) FuturePundit blogs http://www.medworm.com/rss/comments.php?id=1358557 Wed, 09 Apr 2008 04:00:00 +0100 1358557 http://www.medworm.com/index.php?rid=479443&cid=t_287798_87_f&fid=34902&url=http%3A%2F%2Fwww.futurepundit.com%2Farchives%2F004112.html Computers that cost tens of millions of dollars in the 1970s were much slower that computers of today that cost a few hundred dollars in hand-held personal digital assistants (PDAs).... (Source: FuturePundit) FuturePundit blogs http://www.medworm.com/rss/comments.php?id=479443 Sat, 10 Mar 2007 05:00:00 +0100 479443