326 research outputs found
Analysis of MHC class I and II expression in relation to presence of HPV genotypes in premalignant and malignant cervical lesions.
Cervical intraepithelial neoplasia (CIN) grades I to III lesions (n = 94) and squamous cell carcinomas of the uterine cervix (n = 27) were analysed for MHC class I and II expression and presence of HPV genotypes. MHC class I and II expression was studied by immunohistochemistry and HPV typing was performed by general primer- and type-specific primer mediated PCR (GP/TS PCR). Both techniques were performed on paraffin embedded tissue sections. Results show disturbed MHC class I heavy chain expression in CIN I to CIN III, as well as in cervical carcinomas. Upregulated MHC class II expression on dysplastic epithelial cells was also found in the different CIN groups and carcinomas. Prevalence of HPV genotypes increased with the severity of the lesion, mainly due to the contribution of the HPV types 16 and 18. No correlation could be established between the presence of specific HPV genotypes and any MHC expression pattern in the different CIN groups or cervical carcinomas. In some cases these data were confirmed by RNA in situ hybridisation showing HPV 16 E7 transcripts in the same dysplastic/neoplastic cells from which MHC status was determined. The results indicate that local differences may exist in the type of cellular immune response to HPV induced lesions
Single-tube multiplex PCR using type-specific E6/E7 primers and capillary electrophoresis genotypes 21 human papillomaviruses in neoplasia
<p>Abstract</p> <p>Background</p> <p>Human papillomavirus (HPV) <it>E6/E7 </it>type-specific oncogenes are required for cervical carcinogenesis. Current PCR protocols for genotyping high-risk HPV in cervical screening are not standardized and usually use consensus primers targeting HPV capsid genes, which are often deleted in neoplasia. PCR fragments are detected using specialized equipment and extra steps, including probe hybridization or primer extension. In published papers, analytical sensitivity is typically compared with a different protocol on the same sample set.</p> <p>A single-tube multiplex PCR containing type-specific primers was developed to target the <it>E6/E7 </it>genes of two low-risk and 19 high-risk genotypes (HPV6, 11 and 16, 18, 26, 31, 33, 35, 39, 45, 51, 52, 53, 56, 58, 59, 66, 68, 70, 73 and 82) and the resulting short fragments were directly genotyped by high-resolution fluorescence capillary electrophoresis.</p> <p>Results</p> <p>The method was validated using long oligonucleotide templates, plasmid clones and 207 clinical samples of DNA from liquid-based cytology, fresh and formalin-fixed specimens and FTA Microcards<sup>® </sup>imprinted with cut tumor surfaces, swabbed cervical cancers or ejected aspirates from nodal metastases of head and neck carcinomas. Between one and five long oligonucleotide targets per sample were detected without false calls. Each of the 21 genotypes was detected in the clinical sample set with up to five types simultaneously detected in individual specimens. All 101 significant cervical neoplasias (CIN 2 and above), except one adenocarcinoma, contained <it>E6/E7 </it>genes. The resulting genotype distribution accorded with the national pattern with HPV16 and 18 accounting for 69% of tumors. Rare HPV types 70 and 73 were present as the sole genotype in one carcinoma each. One cervical SCC contained DNA from HPV6 and 11 only. Six of twelve oropharyngeal cancer metastases and three neck metastases of unknown origin bore <it>E6/E7 </it>DNA; all but one were HPV16. One neck aspirate contained atypical squames with HPV26.</p> <p>Analytical sensitivity in dilute plasmid mixes was variable.</p> <p>Conclusions</p> <p>A primer-rich PCR readily detects the <it>E6/E7 </it>oncogenes of 21 HPV types in cellular and fixed tissue specimens. The method is straightforward, robust and reproducible and avoids post-PCR enzymatic and hybridization steps while detecting HPV with high clinical sensitivity in significant HPV-related neoplasia regardless of specimen type.</p
Micro-computed tomography of pulmonary fibrosis in mice induced by adenoviral gene transfer of biologically active transforming growth factor-β1
<p>Abstract</p> <p>Background</p> <p>Micro-computed tomography (micro-CT) is a novel tool for monitoring acute and chronic disease states in small laboratory animals. Its value for assessing progressive lung fibrosis in mice has not been reported so far. Here we examined the importance of in vivo micro-CT as non-invasive tool to assess progression of pulmonary fibrosis in mice over time.</p> <p>Methods</p> <p>Pulmonary fibrosis was induced in mice by intratracheal delivery of an adenoviral gene vector encoding biologically active TGF-ß1 (AdTGF-ß1). Respiratory gated and ungated micro-CT scans were performed at 1, 2, 3, and 4 weeks post pulmonary adenoviral gene or control vector delivery, and were then correlated with respective histopathology-based Ashcroft scoring of pulmonary fibrosis in mice. Visual assessment of image quality and consolidation was performed by 3 observers and a semi-automated quantification algorithm was applied to quantify aerated pulmonary volume as an inverse surrogate marker for pulmonary fibrosis.</p> <p>Results</p> <p>We found a significant correlation between classical Ashcroft scoring and micro-CT assessment using both visual assessment and the semi-automated quantification algorithm. Pulmonary fibrosis could be clearly detected in micro-CT, image quality values were higher for respiratory gated exams, although differences were not significant. For assessment of fibrosis no significant difference between respiratory gated and ungated exams was observed.</p> <p>Conclusions</p> <p>Together, we show that micro-CT is a powerful tool to assess pulmonary fibrosis in mice, using both visual assessment and semi-automated quantification algorithms. These data may be important in view of pre-clinical pharmacologic interventions for the treatment of lung fibrosis in small laboratory animals.</p
HPV type concordance in sexual couples determines the effect of condoms on regression of flat penile lesions
We earlier demonstrated, in a randomised clinical trial, that the regression time of flat penile lsions in male sexual partners of women with cervical intraepithelial neoplasia (CIN) was shorter in men who used condoms compared to those who did not. To further evaluate this finding, we examined whether the effect of condom use on the regression of flat penile lesions depends on the presence of human papillomavirus (HPV) type concordance in sexual couples, as determined in cervical and penile scrapes by GP5+/6+ PCR testing. A Cox model with time-dependent covariates showed a beneficial effect of condoms on regression of flat penile lesions in concordant couples (hazard ratio 2.63, 95% CI 1.07–6.48) but not in those who were nonconcordant. When both partners harboured different HPV types, no effect of condoms was found (hazard ratio 0.90, 95% CI 0.27–2.96). Delayed regression of flat penile lesions was associated with either stable lesions or with new penile lesions developing at sites surrounding pre-existing lesions suggesting reinfection of the penile epithelium. We conclude that condom use blocks sexual HPV transmission by preventing reinfection and development of new penile lesions in men who are susceptible to the same type as present in the female partner
Compatible solutes determine the heat resistance of conidia
NWOAF-15507Microbial Biotechnolog
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