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551.
ICP0 is a multi-functional herpes simplex virus type 1 (HSV-1) immediate-early (IE) gene product that contributes to efficient virus growth and reactivation from latency. Here we show that HSV-1-induced cell-cycle arrest at the G2/M border requires ICP0 and Chk2 kinase and that ICP0 expression by transfection or infection induces ATM-dependent phosphorylation of Chk2 and Cdc25C. Infection of cells with a replication-defective mutant virus deleted for all the regulatory IE genes except ICP0 (TOZ22R) induced G2/M arrest whereas a mutant virus deleted in addition for ICP0 (QOZ22R) failed to do so. Chk2-deficient cells and cells expressing a kinase-deficient Chk2 did not undergo cell-cycle arrest in response to TOZ22R infection. Chk2 deficiency diminished the growth of wild-type HSV-1, but not the growth of an ICP0-deleted recombinant virus. Together, these results are consistent with the interpretation that ICP0 activates a DNA damage response pathway to arrest cells in G2/M phase and promote virus growth.  相似文献   
552.

Objective

The incidence of non-alcoholic fatty liver disease (NAFLD) is increasing dramatically affecting up to 30% of the population worldwide. At present, treatment options are limited and pharmacological management of NAFLD has had disappointing results. Some of the best available evidence to improve NAFLD concerns lifestyle modification.

Objective

To detect the degree of weight reduction needed to improve the markers of hepatic function and insulin resistance in type-2 diabetics with NAFLD.

Methods

One hundred type-2 diabetic male patients with NAFLD were included into this study and divided into two equal groups. Group (A) received aerobic exercise training in addition to diet regimen. Group (B) received no treatment intervention.

Results

There was a 26.99%, 40.8%, 33.81%, 32.73%, 37.8% and 15 % reduction in mean values of Alkaline Phosphatase (ALP), Alanine Aminotransferase (ALT), Aspartate Aminotransferase (AST), Gamma - Glutamyltransferase (GGT) and Homeostasis Model Assessment-Insulin Resistance-index (HOMA-IR) and BMI respectively in group (A) at the end of the study. While there were significant differences between mean levels of the investigated parameters in group (A) and group (B) after treatment.

Conclusion

About 15 % reduction in BMI is effective to improve the liver condition and insulin resistance in type-2 diabetics with NAFLD.  相似文献   
553.
Immunoglobulin E (IgE) reactivity to self antigens is well established in vitro by ELISA, inhibition ELISA, Western blot analyses and T cell proliferation experiments. In vivo, IgE-binding self antigens are able to elicit strong type I reactions in sensitized individuals and, in the case of human manganese superoxide dismutase, to elicit eczematous reactions on healthy skin areas of patients suffering from atopic eczema. The reactions against self antigens sharing structural homology with environmental allergens can be plausibly explained by molecular mimicry between common B cell epitopes. For the second class of IgE-binding self antigens without sequence homology to known allergens, it is still unclear if the structures are able to induce a B cell switch to IgE production, or if the reactivity is due to sequence similarity shared with not yet detected environmental allergens. However, in all cases, cross-reactivity is never complete, indicating either a lower affinity of IgE antibodies to self allergens than to the homologous environmental allergens or the presence of additional B cell epitopes on the surface of the environmental allergens, or both. Increasing evidence shows that self allergens could play a decisive role in the exacerbation of long-lasting atopic diseases. However, the only observation supporting a clinical role of IgE-mediated autoreactivity is confined to the fact that IgE levels against self antigens correlate with disease severity.  相似文献   
554.
Rapid immune plaque assays have been developed to quantify biohazard level 4 agents Hendra and Nipah viruses and detect neutralising antibodies to both viruses. The methods rely on the fact that both viruses rapidly generate large syncytia in monolayers of Vero cells within 24 h and that monospecific antiserum to the Hendra virus phosphoprotein (P) detects that protein in both Hendra and Nipah virus-induced syncytia after methanol fixation of virus-infected cells. The P protein is a constituent of the ribonucleoprotein core of the viruses and a component of the viral RNA-dependent RNA polymerase and is made in significant amounts in infected cells. In the immune plaque assay, anti-P antibody is localised by an alkaline phosphatase-linked second antibody and the Western blot substrates 5-bromo-4-chloro-3-indolyl phosphate and p-nitro blue tetrazolium. A modification of the rapid immune plaque assay was also used to detect antibodies to Nipah virus in a panel of porcine field sera from Malaysia and the results showed good agreement between the immune plaque assay and a traditional serum neutralisation test. After methanol fixation, plates can be stored for up to 7 months and may be used in the immune plaque assay to complement the enzyme-linked immunosorbent assay screening of sera for antibodies to Nipah virus. At present, all enzyme-linked immunosorbent assay positive sera are subject to confirmatory serum neutralisation tests. Use of the immune plaque assay may reduce the number of sera requiring confirmatory neutralisation testing for Nipah virus antibodies under biohazard level 4 conditions by identifying those that generate false positive in the enzyme-linked immunosorbent assay.  相似文献   
555.
Regeneration of injured tubular cells occurs after acute tubular necrosis primarily from intrinsic renal cells. This may occur from a pre‐existing intratubular stem/progenitor cell population or from any surviving proximal tubular cell. In this study, we characterize a CD24‐, CD133‐, and vimentin‐positive subpopulation of cells scattered throughout the proximal tubule in normal human kidney. Compared to adjacent ‘normal’ proximal tubular cells, these CD24‐positive cells contained less cytoplasm, fewer mitochondria, and no brush border. In addition, 49 marker proteins are described that are expressed within the proximal tubules in a similar scattered pattern. For eight of these markers, we confirmed co‐localization with CD24. In human biopsies of patients with acute tubular necrosis (ATN), the number of CD24‐positive tubular cells was increased. In both normal human kidneys and the ATN biopsies, around 85% of proliferating cells were CD24‐positive – indicating that this cell population participates in tubular regeneration. In healthy rat kidneys, the novel cell subpopulation was absent. However, upon unilateral ureteral obstruction (UUO), the novel cell population was detected in significant amounts in the injured kidney. In summary, in human renal biopsies, the CD24‐positive cells represent tubular cells with a deviant phenotype, characterized by a distinct morphology and marker expression. After acute tubular injury, these cells become more numerous. In healthy rat kidneys, these cells are not detectable, whereas after UUO, they appeared de novo – arguing against the notion that these cells represent a pre‐existing progenitor cell population. Our data indicate rather that these cells represent transiently dedifferentiated tubular cells involved in regeneration. Copyright © 2012 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.  相似文献   
556.
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