Type I and II interferons (IFNs) exert opposing effects on the progression of multiple sclerosis, even though both IFNs use the signal transducer and activator of transcription 1 (STAT1) as a ...signaling mediator. Here we report that STAT1-deficient mice expressing a transgenic T cell receptor against myelin basic protein spontaneously develop experimental autoimmune encephalomyelitis with dramatically increased frequency. The heightened susceptibility to this autoimmune disease appears to be triggered by a reduced number as well as a functional impairment of the CD4+ CD25+ regulatory T cells in STAT1-deficient animals. Adoptive transfer of wild-type regulatory T cells into STAT1-deficient hosts is sufficient to prevent the development of autoimmune disease. These results demonstrate an essential role of STAT1 in the maintenance of immunological self-tolerance.
We studied the relationships between plasma and saliva concentrations of antiretroviral drugs to explore whether saliva can be used for therapeutic drug monitoring (TDM).
Abacavir (ABC), tenofovir ...(TFV), darunavir (DRV), and raltegravir (RAL) in plasma and saliva from 30 HIV-1-infected patients were quantified using liquid chromatography-tandem mass spectrometry.
Mean saliva-to-plasma concentration ratios were 0.623 (ABC), 0.024 (TFV), 0.065 (DRV), and 0.0135 (RAL), which agree with the plasma protein binding rates except TFV. Significant correlations were evident between saliva and plasma concentrations of ABC, DRV, and RAL.
This study suggests that plasma concentrations of ABC, DRV, and RAL can be estimated from their saliva concentrations and that the saliva concentration of some antiretroviral drugs reflects the unbound drug concentration in plasma. .
Abstract Continuous ambulatory peritoneal dialysis (CAPD) peritonitis is a common problem in patients on peritoneal dialysis, and the bacteriological diagnosis is important for the treatment of this ...condition. We used Hybrizep (a method for detecting the genes of bacteria ingested in phagocytes), to detect the causative bacterium in a 50-year-old woman receiving peritoneal dialysis who was admitted our hospital with bacterial peritonitis. The test, using peritoneal dialysis fluid, was positive for Streptococcus epidermidis . Vancomycin administration led to a good outcome for this patient. The Hybrizep method (which is available on the Japanese National Health system only for the diagnosis of septicemia) was a useful diagnostic approach for a patient on peritoneal dialysis who had peritonitis.
We report five cases of community- and hospital-acquired infections with oseltamivir- and peramivir-resistant A(H1N1)pdm09 viruses possessing the neuraminidase (NA) H275Y mutation during ...January–February 2016 in Japan. One case was hospitalized and was receiving oseltamivir for prophylaxis. The remaining four cases were not taking antiviral drugs at the time of sampling. These cases were geographically distant and epidemiologically unrelated. The five viruses showed ~300-fold rise in IC
50
values against oseltamivir and peramivir, defined as highly reduced inhibition according to the WHO definition. Overall, the prevalence of the H275Y A(H1N1)pdm09 viruses was 1.8 % (5/282). The resistant viruses possessed the V241I, N369 K, and N386 K substitutions in the NA that have been previously reported among A(H1N1)pdm09 to alter transmission fitness. Analysis of Michaelis constant (Km) revealed that two of the isolates had reduced NA affinity to MUNANA, while the other three isolates displayed a slightly decreased affinity compared to the sensitive viruses. Further studies are needed to monitor the community spread of resistant viruses and to assess their transmissibility.
Engagement of the IFN-alphabeta receptor initiates multiple signaling cascades, including activation of the STAT. In this study, we demonstrate that IFN-alphabeta, although antiproliferative in ...wild-type CD4(+) or CD8(+) T cells, act as strong mitogens on their STAT1(-/-) counterparts. Furthermore, IFN-alphabeta exert little effect on apoptosis in wild-type cells, but are potent survival factors in the absence of STAT1. The antiapoptotic response in the absence of STAT1 is predominantly mediated by STAT3, and to a lesser extent by STAT5A/B. In contrast, the mitogenic IFN-alphabeta response gained through the absence of STAT1 is only marginally affected when STAT5A/B expression is also abrogated, but is completely dependent on STAT3 activation. These findings provide the first evidence for a function of STAT3 and STAT5A/B in the IFN-alphabeta response, and support a model in which the IFN-alphabeta receptor initiates both pro- and antiapoptotic responses through STAT1, and STAT3 and STAT5A/B, respectively.
A 23-year-old man was admitted to our hospital with severe thrombocytopaenia. He had unprotected sexual contact 6 weeks earlier. He was diagnosed with acute HIV infection by means of HIV RNA viral ...load testing and HIV-associated thrombocytopaenia. Although his thrombocytopaenia improved immediately with short-term dexamethasone therapy, this effect was not sustained after cessation of therapy. Antiretroviral therapy including raltegravir was initiated, and the patient recovered from severe thrombocytopaenia within several days. The findings from this case suggest that acute HIV infection should be suspected with unexplained thrombocytopaenia, and that antiretroviral therapy is the treatment of choice for severe HIV-associated thrombocytopaenia, even when in the early period following acquisition of the virus.
We treated a case of adult-onset severe-form anaphylactoid purpura. This case had been diagnosed as anaphylactoid purpura pathologically by skin biopsy. However, his clinical manifestations were ...atypical in view of complicated massive gastrointestinal hemorrhage. Intensive therapy including corticosteroid and cyclophosphamide transiently improved his condition. Nevertheless, the beta-D-glucan value in peripheral blood was gradually elevated. Prophylactic use of fluconazole failed to prevent contraction of invasive mycosis. Finally, he suddenly suffered from diffuse cerebral hemorrhage. Postmortem examination revealed systemic invasive aspergillosis as the cause of death. (Internal Medicine 42: 436-442, 2003)
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