Accordingly, we tested the ability of a-clostripain to hydrolyse human hemoglobin since other bacterial proteases can catalyze the release of heme from hemoglobin. Although some hemoglobin degradation was observed, there was no significant difference between the wild-type strain and the ccp mutant, suggesting that a-clostripain does not play a major role in hemoglobin hydrolysis. The clostridial mouse myonecrosis model used in this study, and many other studies, is the only animal model currently available that allows the consistent reproduction of virulent disease. However, since the model involves injection of anaerobic bacteria into healthy oxygenated tissue, an infectious dose of 109 cells is required to establish reproducible disease. This process may mask any role that extracellular enzymes such as a-clostripain, sialidase or collagenase may have during the early stages of the disease process. Therefore, we cannot rule out the possibility that a-clostripain has a role in disease pathogenesis in a natural C. perfringens infection, where a traumatic injury usually leads to the establishment of ischemic conditions, enabling the Dabrafenib proliferation of small numbers of contaminating cells in the muscle tissues leading to a major infection and fulminant gas gangrene. In the past two decades, advances in antiretroviral treatment have resulted in dramatic declines in death rates in countries where treatment is available, transforming a once-fatal disease into a manageable chronic illness. Despite this remarkable achievement, there remain major questions about whether treatment outcomes differ for women and men and what factors may drive such variation. Although a number of studies have examined gender differences in HIV disease progression and in the response to ART, using survival, HIV-1 RNA levels, and lymphocyte subset levels to assess response to treatment, the findings have differed with regard to the association of gender with these measures. Early studies showed a more rapid clinical progression in women, which was attributed to the delay in starting ART and to other gender-related conditions such as discrimination, violence, and stigma. More recently, natural history cohorts observed that early in infection, women have significantly lower amounts of the virus in their blood than do men but suffer the loss of immune cells and develop AIDS just as swiftly as men. A cohort study of 2196 HIV infected treatmentnaive adults conducted in South Africa reported that gender was not significantly associated with survival.