Monday, October 05, 2015
Sunday, October 04, 2015
Saturday, October 03, 2015
Additional research needed to validate the test accuracy
October 1, 2015
A new test that detects virtually any virus that infects people and animals has been developed at Washington University School of Medicine in St. Louis.
Current tests aren’t sensitive enough to detect low virus levels or are limited to detecting only those viruses suspected of being responsible for a patient’s illness.
“With this test, you don’t have to know what you’re looking for,” said the study’s senior author, Gregory Storch, MD, the Ruth L. Siteman Professor of Pediatrics. “It can efficiently detect viruses that are present at very low levels. We think the test will be especially useful in situations where a diagnosis remains elusive after standard testing or in situations in which the cause of a disease outbreak is unknown.”/.../
Scientists estimate there are more than a million viral species, but less than 4,900 viruses have been identified and sequenced
October 1, 2015
Viruses are actually living entities that share a long evolutionary history with cells, researchers report in a study that traces viral evolution back to a time when neither viruses nor cells existed in the forms recognized today.
The new findings appear in an open-access paper in the journal Science Advances.
The origin of viruses remains mysterious because of their diverse and patchy molecular and functional makeup. Although numerous hypotheses have attempted to explain viral origins, none is backed by substantive data. We take full advantage of the wealth of available protein structural and functional data to explore the evolution of the proteomic makeup of thousands of cells and viruses. Despite the extremely reduced nature of viral proteomes, we established an ancient origin of the “viral supergroup” and the existence of widespread episodes of horizontal transfer of genetic information. Viruses harboring different replicon types and infecting distantly related hosts shared many metabolic and informational protein structural domains of ancient origin that were also widespread in cellular proteomes. Phylogenomic analysis uncovered a universal tree of life and revealed that modern viruses reduced from multiple ancient cells that harbored segmented RNA genomes and coexisted with the ancestors of modern cells. The model for the origin and evolution of viruses and cells is backed by strong genomic and structural evidence and can be reconciled with existing models of viral evolution if one considers viruses to have originated from ancient cells and not from modern counterparts.