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This study analyzed macrophage inflammatory protein-2 (MIP-2) production and neutrophil recruitment in urinary tract in response to Pseudomonas aeruginosa in an ascending model of urinary tract infection (UTI) in mice. Both planktonic and biofilm cells of P. aeruginosa were used for inducing UTI in mice. MIP-2 levels determined in urine, bladder and kidney showed maximum MIP-2 production 6 h postinfection, which correlated with neutrophil recruitment. Biofilm cells showed significantly more MIP-2 production and neutrophil recruitment. However, no correlation between bacterial numbers and neutrophil recruitment was observed in urine and kidney tissue. The role of MIP-2 and neutrophils in relation to the persistence of P. aeruginosa in the urinary tract of mice is discussed.  相似文献   
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Stand-replacing fires influence soil nitrogen availability and microbial community composition, which may in turn mediate post-fire successional dynamics and nutrient cycling. However, fires create patchiness at both local and landscape scales and do not result in consistent patterns of ecological dynamics. The objectives of this study were to (1) quantify the spatial structure of microbial communities in forest stands recently affected by stand-replacing fire and (2) determine whether microbial variables aid predictions of in situ net nitrogen mineralization rates in recently burned stands. The study was conducted in lodgepole pine (Pinus contorta var. latifolia) and Engelmann spruce/subalpine fir (Picea engelmannii/Abies lasiocarpa) forest stands that burned during summer 2000 in Greater Yellowstone (Wyoming, USA). Using a fully probabilistic spatial process model and Bayesian kriging, the spatial structure of microbial lipid abundance and fungi-to-bacteria ratios were found to be spatially structured within plots two years following fire (for most plots, autocorrelation range varied from 1.5 to 10.5 m). Congruence of spatial patterns among microbial variables, in situ net N mineralization, and cover variables was evident. Stepwise regression resulted in significant models of in situ net N mineralization and included variables describing fungal and bacterial abundance, although explained variance was low (R2<0.29). Unraveling complex spatial patterns of nutrient cycling and the biotic factors that regulate it remains challenging but is critical for explaining post-fire ecosystem function, especially in Greater Yellowstone, which is projected to experience increased fire frequencies by mid 21st Century.  相似文献   
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Iron-limiting conditions have been reported to be prevalent in the milieu of urinary tract. In the present investigation, effect of iron on virulence of uropathogenic Pseudomonas aeruginosa in planktonic and biofilm cell mode was studied. Significant enhancement in elaboration of all the virulence traits along with increased adherence to uroepithelial cells and decreased phagocytosis of P. aeruginosa was observed following growth in iron-deplete medium. On the contrary, decrease in all these parameters except phagocytosis was observed when P. aeruginosa was grown in iron-rich medium. In vivo, P. aeruginosa grown in iron-deplete medium showed increased renal bacterial load and tissue pathology in a mouse model of ascending urinary tract infection compared with organisms grown in iron-replete medium. The results of the present study may help in understanding host–parasite interaction and in developing alternative preventive approach against P. aeruginosa induced urinary tract infections.  相似文献   
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Cytomorphological spectrum in gynaecomastia: a study of 389 cases The objective of this study was to document the spectrum of cytomorphological features in aspirates from gynaecomastia. During a 22-year period (July 1979 to June 2001) fine needle aspirations (FNA) were conducted on 651 males with a breast lesion. Fine needle aspirate slides from 529 benign cases were reviewed along with the histological sections of 54 cases where available. Of the 529 FNA, 140 were excluded (105 unsatisfactory, five cystic fluid aspirated, 30 inflammatory lesions). In 134 of 389 cases reviewed florid gynaecomastia was observed while the remainder showed benign ductal cells (BDC) in varying quantities from less than five to more than 25 groups. Of the 134 cases with florid gynaecomastia, 49 had a fibroadenoma-like picture (FLP), where a large number of BDC fragments with a staghorn configuration, prominent stromal fragments with contoured stroma and bare bipolar nuclei were seen abundantly in all cases. In 85 cases the features resembled fibroadenomatoid hyperplasia (FH), with only an occasional staghorn configuration of BDC seen in 82% of the cases. In 83% of cases stromal fragments of varying proportions were seen but a contoured stroma was seen in only 3.5% of cases. Both stromal and epithelial atypia were seen in 41% and 86% cases, respectively, of FLP, and in 7% and 69% cases of FH. Columnar cells, apocrine cells and foam cells were seen in approximately similar quantities in both the lesions. Vascularized stroma was seen in 22% of the cases with FLP but in only 4.5% of cases those with FH. Cytohistological correlation performed in 54 cases showed marked variation. Fine needle aspirates showed florid changes in 13 of the 41 cases of simple gynaecomastia and two of the eight cases with florid gynaecomastia on tissue sections. In conclusion, a wide spectrum of morphological features are encountered in FNA from benign male breast lesions. It is important to recognize these to avoid a false-positive diagnosis.  相似文献   
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Inhibition of hepatitis B virus in mice by RNA interference   总被引:137,自引:0,他引:137  
Hepatitis B virus (HBV) infection substantially increases the risk of chronic liver disease and hepatocellular carcinoma in humans. RNA interference (RNAi) of virus-specific genes has emerged as a potential antiviral mechanism. Here we show that RNAi can be applied to inhibit production of HBV replicative intermediates in cell culture and in immunocompetent and immunodeficient mice transfected with an HBV plasmid. Cotransfection with plasmids expressing short hairpin RNAs (shRNAs) homologous to HBV mRNAs induced an RNAi response. Northern and Southern analyses of mouse liver RNA and DNA showed substantially reduced levels of HBV RNAs and replicated HBV genomes upon RNAi treatment. Secreted HBV surface antigen (HBsAg) was reduced by 94.2% in cell culture and 84.5% in mouse serum, whereas immunohistochemical detection of HBV core antigen (HBcAg) revealed >99% reduction in stained hepatocytes upon RNAi treatment. Thus, RNAi effectively inhibited replication initiation in cultured cells and mammalian liver, showing that such an approach could be useful in the treatment of viral diseases.  相似文献   
58.
Bioprocess and Biosystems Engineering - The study investigated an integrated bioprocessing of raw and by-products from sugarcane and dairy industries for production of non-digestible prebiotic and...  相似文献   
59.
Mathur S  Verm K 《Acta cytologica》2005,49(4):373-377
OBJECTIVE: To study the morphologic features of peripheral T-cell lymphoma, not otherwise specified (PTCL, NOS) on fine needle aspiration cytology (FNAC) smears and to identify cytomorphologic features that would delineate them from features of cases of Hodgkin's lymphoma (HL). CONCLUSION: Fourteen cases each of PTCL, NOS, and HL with adequate FNAC smears were retrieved. These cases were analyzed for 12 cytomorphologic features: presence of atypical lymphoid cells, percentage of large lymphoid cells, lymphoid cells with cleaved/indented nuclei, typical Reed-Sternberg (RS) cells, mononuclear cells with prominent eosinophilic macronucleoli, mononuclear cells with prominent nucleoli, histiocytes, eosinophils, plasma cells, polymorphonuclear leukocytes, vessels and perivascular clustering of atypical mononuclear/atypical lymphoid cells. Each of these features was evaluated for its presence or absence and was semiquantitated on a scale from 0 to +3. RESULTS: The presence of atypical lymphoid cells with a spectrum ranging from small to intermediate and large was seen exclusively in cases of PTCL. Lymphoid cells with cleaved or indented nuclei, endothelium-lined vessels with perivascular clustering of tumor cells and absence of typical RS cells, and mononuclear cells with prominent eosinophilic macronucleoli emerged as the parameters significant in not only diagnosing cases of PTCL, NOS, but also in their delineation from cases of HL. CONCLUSION: A careful analysis of cytomorphologic features can be useful in at least suggesting a diagnosis of PTCL and help to distinguish that diagnosis from HL, which the features may mimic. Immunophenotyping and molecular studies are important in arriving at a definitive diagnosis.  相似文献   
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