Search results
Results from the WOW.Com Content Network
Robert Hermann Koch (11 December 1843 – 27 May 1910) was a German physician who developed Koch's postulates. [1] Koch's postulates (/ k ɒ x / KOKH) [2] are four criteria designed to establish a causal relationship between a microbe and a disease. The postulates were formulated by Robert Koch and Friedrich Loeffler in 1884, based on earlier ...
Diabetes mellitus type 1 is associated with viral species from the enterovirus genus, [53] [54] specifically echovirus 4 [55] and Coxsackie B virus (the latter it is thought may infect and destroy the insulin producing beta-cells in the pancreas and also damage these cells via indirect autoimmune mechanisms).
Although Koch's postulates are often inapplicable, they remain heuristic, and the authority of "fulfilling Koch's postulates" is still invoked in medical science, though often in modified form, [38] as in the identification of HIV-1 as the cause of AIDS or the identification of SARS coronavirus as the cause of SARS. [39] [40] [41]
In 1996, Fredricks and Relman suggested the following postulates for the novel field of microbial pathogenesis. [2] [3](i) A nucleic acid sequence belonging to a putative pathogen should be present in most cases of an infectious disease.
Based on these experiments, he devised criteria for establishing a causal link between a microorganism and a disease and these are now known as Koch's postulates. [18] Although these postulates cannot be applied in all cases, they do retain historical importance to the development of scientific thought and are still being used today. [19]
HIV found in tissue samples from a Norwegian sailor who died around 1976. [40] Two species of HIV infect humans: HIV-1 and HIV-2. More virulent and more easily transmitted, HIV-1 is the source of the majority of HIV infections throughout the world, while HIV-2 is not as easily transmitted and is largely confined to West Africa. [41]
The genome and proteins of HIV (human immunodeficiency virus) have been the subject of extensive research since the discovery of the virus in 1983. [1] [2] "In the search for the causative agent, it was initially believed that the virus was a form of the Human T-cell leukemia virus (HTLV), which was known at the time to affect the human immune system and cause certain leukemias.
These studies found that >95% of CD4 T cells die because of abortive HIV infection. [9] These dying cells are resting and thus are nonpermissive for productive HIV infection. Full viral replication was limited to the ~5% of activated CD4 T cells present in these tissues; these cells die by apoptosis. [10] Abortive HIV infection occurs due to ...