Popular Articles

Tufts Health Plan Foundation Grant Awarded To Hebrew SeniorLife
Hebrew SeniorLife has received a $105,000 grant from the Tufts Health Plan Foundation for the expansion and implementation of three evidence-based healthy aging programs designed to disseminate preventive health-related information to seniors in the community.
generic viagra
Health Information Technology And Health Care Reform Must Be Well-Aligned To Improve Health And Lower Costs
Dramatic improvements in health and reductions in cost growth are achievable if efforts to boost health information technology (IT) are aligned with broader health care reform, a group of three influential non-profit organizations said today.
News of the day
CEL-SCI Expands Testing Of Its Vaccine To Determine Efficacy Against More Virulent Strain Of H1N1 Swine And Other Influenza Viruses
CEL-SCI Corporation (NYSE Amex: CVM) announced that it is expanding the pre-clinical testing of its flu vaccine, utilizing its proprietary L.E.A.P.S. technology (Ligand Epitope Antigen Presentation System) to determine its efficacy against the more dangerous and virulent virus strains that may arise during the up coming winter flu season. The Company has begun pre-clinical formulation, evaluation and testing of a new application of its L.E.A.P.S vaccine, which will allow the targeting of "mutated" versions of H1N1 swine and other influenza viruses. It is believed that the influenza virus may mutate and evolve between now and the winter flu season. In conjunction with the testing, CEL-SCI has produced several L.E.A.P.S. flu vaccines that focus on the conserved, non changing epitopes of the different strains of Type A Influenza viruses (H1N1, H5N1, H3N1, etc.), including "swine", "avian or bird", and "Spanish Influenza", in order to minimize the chance of viral "escape by mutations" from immune recognition. CEL-SCI"s L.E.A.P.S. flu vaccine contains epitopes known to be associated with immune protection against influenza in animal models. The Company had previously announced that it had begun pre-clinical testing of swine and H1N1 flu viruses, which were non-mutated versions of the virus.
Cardiovascular

DNA Deletion Makes Swedish Chlamydia 'Invisible'

New sequencing and analysis of six strains of Chlamydia will result in improved diagnosis of the sexually transmitted infection. This study provides remarkable insights into a new strain of Chlamydia that was identified in Sweden in 2006 after spreading rapidly across the country by evading most established diagnostic tests. The results also reveal more about the evolution of the Chlamydia trachomatis bacterium, which is the most common cause of sexually transmitted infections (STIs) globally. The long-term effects of an undetected Chlamydia infection include infertility and ectopic pregnancy. Long-term eye infection by Chlamydia is also the leading cause of preventable blindness in the developing world. As part of a long-standing collaboration between the Wellcome Trust Sanger Institute and University of Southampton, the team of researchers focused on six strains of Chlamydia. Of particular interest to the team was the new Swedish strain provided by collaborators at Malmo University Hospital, Sweden. The genome of the Swedish strain features an evolutionary "hiccup" that allowed it to go undetected in Sweden for several months. Indeed, doctors thought that the numbers of cases of Chlamydia were falling, when the opposite was true. Through non-diagnosis, this version of Chlamydia spread silently. The reason: a deletion of the region of genetic information used to diagnose the presence of Chlamydia. "The medical and research communities need to heed this warning," says Dr Helena Seth-Smith, investigator at the Sanger Institute and lead author on the study. "Chlamydia infections appeared to be in decline in Sweden, but this could not have been further from the truth. The loss of a segment of genetic code made the tests completely powerless to detect this particular strain of Chlamydia. This type of evolution to evade diagnosis could occur in other infectious bacteria." "We have found more stable genetic targets - these should be the regions against which we design diagnostic tests." The deletion - 377 letters of genetic code - occurred on the plasmid of the bacterium. Plasmids are small, circular molecules of DNA that are located outside the chromosome. Chlamydial plasmids have been shown to vary little between different strains of Chlamydia, and are present in larger quantities than the chromosome. This makes them ideal candidate targets for diagnostic tools. Clinical tests have focused on one region of the bacterial plasmid - a gene of unknown function which is largely deleted in the new Swedish strain. "We have confidently placed great reliance on nucleic acid based diagnostic tests for many years," explains Professor Ian Clarke, University of Southampton, senior author on the study, "but we must always be alert to changes in the biology of this organism. Chlamydia are notoriously difficult to study in the laboratory and genomics can make a vital contribution to adding to our understanding of this insidious parasite." After careful analysis of the newly sequenced plasmids of these strains, the team have identified the regions of the plasmid that vary least between strains. "These are thought to be important in the stability of the plasmid, and so tests on these regions should prove more reliable," explained co author Dr. Pete Marsh from the Southampton Health Protection Agency." "This is a truly remarkable turn of events," explains Dr Nicholas Thomson, principal investigator at the Sanger Institute. "It is an example today of evolution in action: we believe that diagnostic tests that target one region of the Chlamydial plasmid have allowed the Swedish strain, very quickly, to become the dominant strain in that country." "Paradoxically, the efforts of humans to control the spread of the disease may well have been the cause that shaped the development and spread of this new strain." Chlamydia is a bacterial parasite that only grows within human cells: as a result there is not a great deal of exchange of genetic material between strains. The stability of the link between the bacterial chromosome and the plasmid DNA was also established in this study, reinforcing confidence in the plasmid as the target for diagnostic tests. Publication Details Seth-Smith H. et al. (2009) Co-evolution of genomes and plasmids within Chlamydia trachomatis and the emergence in Sweden of a new variant strain. BMC Genomics Published online before print as doi: Funding This work was supported by the Wellcome Trust and the MRC sexual health and HIV grant scheme. Participating Centres * Molecular Microbiology Group, University Medical School, Southampton General Hospital, Southampton, UK * The Pathogen Sequencing Unit, The Wellcome Trust Sanger Institute, Hinxton, Cambridge, UK * Department of Clinical Microbiology, Malmo University Hospital, Malmo, Sweden * Health Protection Agency South East, Southampton General Hospital, Southampton, UK * Department of Obstetrics and Gynaecology, Malmo University Hospital, malmo, Sweden * Viral Diseases Programme, Medical Research Council, Banjul, The Gambia/Clinical Research Unit, Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine London, UK Don Powell Wellcome Trust Sanger Institute


Add your comment:
Name:
Site address: http://
Your message:
Enter today\\\\'s date, 2 digits
(spam protection):