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1.
Mice treated with a single injection of formalin-fixed Coxiella burnetii showed a significant increase in resistance to vaccinia virus (VV) infection compared to untreated mice. C. burnetii stimulated dramatically high levels of nitric oxide (NO) in the serum of treated mice, suggesting that NO might play a role in resistance to virus infection. To test this hypothesis, the effect of C. burnetii treatment on VV replication was examined in NOS2-/- and wild-type mice. C. burnetii treatment inhibited VV replication in both the knockout and wild-type mice but the effect was significantly greater in the NOS2-/- mice. Experiments in IFNgamma receptor knockout mice indicated that the nonspecific antiviral immunity induced by C. burnetii was dependent on IFNgamma and not NO. In the absence of NO, indoleamine 2,3-dioxygenase (IDO) was increased in C. burnetii-treated mice and this may contribute to the accelerated virus clearance in NOS2-/- mice.  相似文献   
2.
The DNA sequence of the simian varicella virus genome   总被引:5,自引:0,他引:5  
Gray WL  Starnes B  White MW  Mahalingam R 《Virology》2001,284(1):123-130
In nonhuman primates, simian varicella virus (SVV) causes a natural disease which is clinically similar to human varicella-zoster virus (VZV) infections. The SVV and VZV genomes are similar in size and structure and share extensive DNA homology. This report presents the complete DNA sequence of the SVV genome. SVV DNA is 124,138 bp in size, 746 bp shorter than VZV DNA, and 40.4% G + C. The viral genome includes a 104,104-bp unique long component bracketed by 8-bp inverted repeat sequences and a short component composed of a 4904-bp unique short region bracketed by 7557-bp inverted repeat sequences. A total of 69 distinct SVV open reading frames (ORFs) were identified, including three that are duplicated within the inverted repeats of the short component. Each of the SVV ORFs shares extensive homology to a corresponding VZV gene. The only major difference between SVV and VZV DNA occurs at the leftward terminus. SVV lacks a VZV ORF 2 homolog. In addition, SVV encodes an 882-bp ORF A that is absent in VZV, but has homology to the SVV and VZV ORF 4. The results of this study confirm the relatedness of SVV and VZV and provide further support for simian varicella as a model to investigate VZV pathogenesis and latency.  相似文献   
3.
Microcystic adnexal carcinoma: an immunohistochemical reappraisal.   总被引:1,自引:0,他引:1  
Even though immunohistochemical comparisons of microcystic adnexal carcinoma vs infiltrative basal cell carcinoma and desmoplastic trichoepithelioma exist, they are mostly restricted to the use of a single stain. In addition, a comparison with squamous cell carcinoma has not been reported previously. In this study, we compare the expression of cytokeratin (CK) 15, CK7, CK20, CK903, carcinoembryonic antigen (CEA), CD10, CD15 and BerEP4 in 13 microcystic adnexal carcinoma, eight desmoplastic trichoepithelioma, 10 infiltrative basal cell carcinoma, and eight squamous cell carcinoma of which five exhibited ductal differentiation. We found that the majority of microcystic adnexal carcinoma (92%) and desmoplastic trichoepithelioma (100%) cases expressed CK15 while the infiltrative basal cell carcinoma and squamous cell carcinoma cases were all negative. Forty percent of infiltrative basal cell carcinoma expressed CK7; while only two microcystic adnexal carcinoma cases (15%) and one squamous cell carcinoma with ductal differentiation (12%) expressed CK7 in the remaining three tumor categories. None of the desmoplastic trichoepithelioma expressed CK7. All tumors were strongly positive for CK903. While the neoplastic cells were negative, luminal staining of ductal structures was noted for CK7, CD15 and CEA in some of the microcystic adnexal carcinoma, desmoplastic trichoepithelioma and squamous cell carcinoma with ductal differentiation cases. Sixty percent of infiltrative basal cell carcinoma, 31% of microcystic adnexal carcinoma, and 25% of squamous cell carcinoma express CD10. BerEP4 expression was noted in 38% of microcystic adnexal carcinoma, 57% of desmoplastic trichoepithelioma, 100% of infiltrative basal cell carcinoma, and 38% of squamous cell carcinoma. In conclusion, we found CK15 to be a useful marker in distinguishing microcystic adnexal carcinoma from infiltrative basal cell carcinoma and squamous cell carcinoma with ductal differentiation. Our experience indicates that microcystic adnexal carcinoma and desmoplastic trichoepithelioma have a similar immunohistochemical profile that is, CK15+ and BerEP4+/-; thus, additional studies are needed to separate these two entities.  相似文献   
4.
We used polymerase chain reaction to analyze the prevalence and distribution of latent simian varicella virus (SVV) in ganglionic and nonganglionic tissues from nine African green monkeys experimentally infected with SVV. Primers specific for three different regions of the SVV genome were used for amplification. SVV DNA sequences were detected in trigeminal ganglia from seven of nine monkeys and in thoracic ganglia from seven of nine monkeys. Analysis of DNA from nonneuronal tissues of three monkeys and from adrenal glands of nine monkeys revealed the presence of SVV-specific sequences in the adrenal gland of one monkey. The results indicate that, like human varicella, SVV becomes latent primarily in ganglia at multiple levels of the neuraxis, and more than one region of the SVV genome is present in latently infected ganglia. SVV latency in primates may be a useful model for varicella latency in humans.  相似文献   
5.
T cell activation and disease severity in HIV infection.   总被引:14,自引:3,他引:14       下载免费PDF全文
In vitro studies have indicated that T lymphocyte activation may be of importance in the pathogenesis of HIV infection. In order to define the role of immune activation in vivo, we assessed the expression of the T cell activation markers HLA-DR and CD25 by flow cytometry in peripheral blood in relation to disease severity and the surrogate markers CD4 and beta 2-microglobulin in 157 patients with HIV infection and 53 healthy seronegative blood donors. Percentage levels of CD3+HLA-DR+ T lymphocytes were significantly higher (P < 0.0001) and percentage levels of CD3+CD25+ T lymphocytes significantly lower (P < 0.0001) in all HIV+ patients compared with controls. A significant correlation was observed between increasing percentage levels of CD3+HLA-DR+ T lymphocytes and both declining CD4 counts (r = 0.52; P < 0.001) and increasing beta 2-microglobulin levels (r = 0.56; P < 0.001). Percentage levels of CD4+HLA-DR+ and CD4+ CD25+ lymphocytes were significantly higher in all HIV+ patients compared with controls (P < 0.001). Levels of activated (HLA-DR+ and CD25+) CD4+ lymphocytes showed a significant step-wise linear increase with increasing disease severity (P < 0.001). High levels of CD3+HLA-DR+ T lymphocytes were found in a greater proportion (81.8%) of asymptomatic HIV+ patients (Centres for Disease Control (CDC) group II) than low CD4 counts (51.5%) (P < 0.001). Compared with controls, HIV+ patients had higher percentage levels of CD8+HLA-DR+ lymphocytes (P < 0.001), but similar levels of CD8+CD25+ lymphocytes. These results indicate that T cell activation is not only a consistent but also an early feature in HIV infection. Monitoring levels of activated T cells and their subsets is of value in assessing progression of HIV-related disease.  相似文献   
6.
The pathogenesis of human asthma and the development of key features of pulmonary allergy in mouse models has been critically linked to IL-13. Analyses of the receptor components employed by IL-13 have shown that delivery of this cytokine to the airways of naive IL-4Ralpha gene targeted (IL-4Ralpha(-/-)) mice fails to induce disease, suggesting that this membrane protein is critical for transducing IL-13-mediated responses. The current study demonstrates that, in contrast to naive mice, T helper 2 bias, airways hyperreactivity (AHR) and tissue eosinophilia develop in Ovalbumin-sensitized IL-4Ralpha(-/-) mice and that these responses can be inhibited by the IL-13 antagonist sIL-13Ralpha2Fc. Therefore, antigen stimulation induces an IL-13-regulated response that is independent of IL-4Ralpha. To determine the role of IL-5 and eosinophils in the development of disease in antigen-exposed IL-4Ralpha(-/-) mice, pulmonary allergy was examined in mice deficient in both factors. IL-4Ralpha/IL-5(-/-) mice were significantly defective in their ability to produce IL-13 and failed to develop AHR, suggesting that IL-5 indirectly regulates AHR in allergic IL-4Ralpha(-/-) mice by an IL-13-dependent mechanism. Collectively, these results demonstrate that IL-13-dependent processes regulating the development of AHR and T helper bias persist in the in the lungs of allergic IL-4Ralpha(-/-) mice.  相似文献   
7.
8.
A 45-year-old man with a long-standing history of duodenal ulcer presented with symptoms and signs of perforation peritonitis. He also had lesions of pemphigus vulgaris throughout the body, involving both skin and mucous membranes. Care was taken to avoid pressure and friction during placement of monitoring devices, intravenous and arterial lines. Since the patient had to undergo exploratory laparotomy, intubation was performed in an atraumatic manner after rapid sequence induction. However, there was minor bleeding from the mucous lesions of the oral cavity, which was controlled by a saline adrenaline throat pack. The patient was extubated at the end of the surgery and steroids were continued in the peri-operative period.  相似文献   
9.
10.
Mitochondria play a critical role in the cardiomyocyte physiology by generating majority of the ATP required for the contraction/relaxation through oxidative phosphorylation (OXPHOS). Aging is a major risk factor for cardiovascular diseases (CVD) and mitochondrial dysfunction has been proposed as potential cause of aging. Recent technological innovations in Seahorse XFe24 Analyzer enhanced the detection sensitivity of oxygen consumption rate and proton flux to advance our ability study mitochondrial function. Studies of the respiratory function tests in the isolated mitochondria have the advantages to detect specific defects in the mitochondrial protein function and evaluate the direct mitochondrial effects of therapeutic/pharmacological agents. Here, we provide the protocols for studying the respiratory function of isolated murine cardiac mitochondria by measuring oxygen consumption rate using Seahorse XFe24 Analyzer. In addition, we provide details about experimental design, measurement of various respiratory parameters along with interpretation and analysis of data.  相似文献   
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