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71.
Telomerase Repeat Amplification Protocol (TRAP) in situ was performed on cytospin preparations from 65 effusions from the serous cavities (45 pleural and 19 ascitic fluids and one pericardial fluid) submitted for routine diagnosis and the results were correlated to cytological morphology. Three types of cells with nuclear fluorescence were identified: malignant cells, hyperplastic mesothelial cell and lymphocytes. Of 38 cytologically malignant effusions, 12 showed strong reactivity in all malignant cells, three strong reactivity in part of the malignant population, whereas 12 showed moderate reactivity in the whole and five in part of the malignant population, respectively. In five malignant effusions weak reactivity was found in all (one case) and in scattered (four cases) malignant cells. Two effusions contained telomerase-negative malignant cells. Two pleural and two ascitic fluids contained proliferative mesothelial cells with weak or, in one case, moderate reactivity. Lymphocytes usually showed weak telomerase activity. Telomerase was expressed in almost all malignant tumours metastatic to serous cavities. Heterogeneity in tumour populations was demonstrated, which may have diagnostic implications, especially in cytology. Weak or moderate reactivity was found in lymphocytes and in some mesothelial proliferations and may explain the low specificity for malignancy sometimes obtained with the TRAP extract method. The weak reactivity found in lymphocytes may reduce the specificity when the extract method is used but causes no diagnostic problem with the TRAP in situ method. 相似文献
72.
Vilse, a conserved Rac/Cdc42 GAP mediating Robo repulsion in tracheal cells and axons 总被引:3,自引:0,他引:3
Lundström A Gallio M Englund C Steneberg P Hemphälä J Aspenström P Keleman K Falileeva L Dickson BJ Samakovlis C 《Genes & development》2004,18(17):2161-2171
Slit proteins steer the migration of many cell types through their binding to Robo receptors, but how Robo controls cell motility is not clear. We describe the functional analysis of vilse, a Drosophila gene required for Robo repulsion in epithelial cells and axons. Vilse defines a conserved family of RhoGAPs (Rho GTPase-activating proteins), with representatives in flies and vertebrates. The phenotypes of vilse mutants resemble the tracheal and axonal phenotypes of Slit and Robo mutants at the CNS midline. Dosage-sensitive genetic interactions between vilse, slit, and robo mutants suggest that vilse is a component of robo signaling. Moreover, overexpression of Vilse in the trachea of robo mutants ameliorates the phenotypes of robo, indicating that Vilse acts downstream of Robo to mediate midline repulsion. Vilse and its human homolog bind directly to the intracellular domains of the corresponding Robo receptors and promote the hydrolysis of RacGTP and, less efficiently, of Cdc42GTP. These results together with genetic interaction experiments with robo, vilse, and rac mutants suggest a mechanism whereby Robo repulsion is mediated by the localized inactivation of Rac through Vilse. 相似文献
73.
Elevated levels of IgG and IgG4 to Malassezia allergens in atopic eczema patients with IgE reactivity to Malassezia 总被引:2,自引:0,他引:2
Johansson C Tengvall Linder M Aalberse RC Scheynius A 《International archives of allergy and immunology》2004,135(2):93-100
BACKGROUND: The opportunistic yeast Malassezia is considered to be one of the factors that can contribute to atopic eczema (AE). Elevated serum IgE levels, T-cell proliferation and positive skin prick test (SPT) and atopy patch test (APT) reactions to Malassezia are found among AE patients. METHODS: Sera from 127 AE patients, 14 patients with seborrheic dermatitis (SD) and 33 healthy controls were investigated for IgE and IgG4 to M. sympodialis extract and four recombinant Malassezia allergens; rMala s 1, rMala s 5, rMala s 6, and rMala s 9. In addition, IgG to the recombinant allergens was analyzed. The IgG and IgG4 levels were compared to IgE levels and in vivo reactions (SPT and APT) to Malassezia. RESULTS: AE patients with serum IgE levels >0.35 kU/l to M. sympodialis extract had significantly higher IgG4 levels to M. sympodialis extract than AE patients without detectable serum IgE to M. sympodialis extract, SD patients and healthy controls. Among the AE patients with and without detectable serum IgE to M. sympodialis extract, respectively, there were no differences in IgG4 levels between patients with positive or negative in vivo reactions to M. sympodialis extract. IgG4 to the rMala s allergens was almost exclusively found among patients with IgE to the same allergen. Within the four tested rMala s allergens, most IgG4 reactions were found to rMala s 6, an allergen with homology to cyclophilin. CONCLUSIONS: Elevated serum IgG4 to M. sympodialis extract accompanies elevated serum IgE to the extract. This is further confirmed by the association between IgG/IgG4 and IgE to recombinant Malassezia allergens. 相似文献
74.
Objective
To investigate women's expectations of routine ultrasound and experiences when soft markers were discovered: what the disclosure meant, how it affected them, how they experienced the information given and why they did or did not choose amniocentesis.Design
Semi-structured, in-depth interviews were conducted with 11 women 25-30 weeks into the pregnancy, 7-13 weeks after the discovery of a soft marker.Findings
Women lacked knowledge about the potential of the scan and detection of soft markers created strong emotional reactions that women thought could have been alleviated by prior information about potential findings. Information in connection with the scan was perceived as insufficient. Decision about amniocentesis was affected by attitudes to disability, anxiety about fetal loss due to the procedure, need for certainty by a diagnostic test, and partner's opinion.Conclusions
Women were shocked by the unexpected and sometimes unwanted information on elevated risk for a chromosomal aberration for which they lacked any preparation. Because this event often has long-lasting effects on the pregnancy, models of information that are efficient in promoting informed decisions are imperative.Practice implications
Both women and their partners need relevant information before and in connection with ultrasound scan to be able to make informed choices. 相似文献75.
von Wattenwyl R Blumenthal B Heilmann C Golsong P Poppe A Beyersdorf F Siepe M 《ASAIO journal (American Society for Artificial Internal Organs : 1992)》2012,58(3):268-274
The transplantation of skeletal myoblasts (SkM) might improve cardiac function after myocardial infarction via paracrine action. We used scaffold-based cell transfer by using vascular endothelial growth factor (VEGF)-overexpressing myoblasts. Skeletal myoblasts were isolated and expanded from newborn Lewis rats. Cells were transfected with pCINeo-VEGF(121) and seeded on polyurethane (PU) scaffolds. The seeded scaffolds were epicardially implanted in rats 2 weeks after myocardial infarction (group: PU-VEGF-SkM). Before this intervention and 6 weeks later, pressure/volume loops were analyzed followed by histology. Additional study groups (n = 10 per group) were injected with VEGF-overexpressing myoblasts (Inj-VEGF-SkM) or unmodified myoblasts (Inj-SkM) or underwent a sham operation. Overexpression of VEGF was verified in vitro. The transplantation of growth factor producing myoblast-seeded scaffolds resulted in enhanced angiogenesis of ischemically damaged myocardium in vivo. However, the infarction size was not reduced. In group Inj-SkM, hemodynamics remained unchanged. Systolic function as measured by dP/dt(max) was not significantly altered in PU-VEGF-SkM (preinterventionally 2,156 ± 1,222 mmHg vs. postinterventionally 2,134 ± 850 mmHg). Other systolic function and diastolic function parameters as measured by dP/dt(min), tau, and pressure half-time were not restored in groups PU-VEGF-SkM and Inj-VEGF-SkM either. Transplantation of VEGF-overexpressing skeletal myoblasts leads to neovascularization in infarcted hearts. No functional myocardial recovery was observed. Scaffold-based transfer of genetically-modified cells remains a useful tool to study paracrine stem cell action. 相似文献
76.
Haagsman A Reuter G Duizer E Nagy G Herremans T Koopmans M Szücs G 《Journal of medical virology》2007,79(7):927-930
Many cases of acute hepatitis remain undiagnosed and the hepatitis E virus (HEV) is emerging in industrialized countries. The aim of this study was to assess the role HEV as causative agent in acute non-A, non-B, and non-C hepatitis patients in Hungary. 10.5% of the 264 acute non-A, non-B, and non-C hepatitis patients tested had anti-HEV IgG and 1.9% had anti-HEV IgM as tested by ELISA. After confirmation by Western blot 6.1% of the acute non-A, non-B, and non-C hepatitis patients had anti-HEV IgG antibodies only and 1.1% of the patients had both IgG and IgM. All 19 patients that were positive for anti-HEV IgG and/or IgM tested negative for HEV RNA by PCR. Only a small proportion of the acute hepatitis cases in the southwest of Hungary are assumed to be attributed to HEV infection, however, hepatitis E should be considered along with hepatitis A, B, and C in the diagnosis of acute hepatitis. 相似文献
77.
Dejmek A Naucler P Smedjeback A Kato H Maeda M Yashima K Maeda J Hirano T 《Diagnostic cytopathology》2007,35(8):493-497
The purpose of this study was to test napsin A as a diagnostic marker of metastatic lung adenocarcinoma in pleural effusions, and to compare its performance with TTF-1. Napsin A and TTF-1 reactivities were determined immunohistochemically on formalin-fixed paraffin embedded cell blocks from 50 pleural effusion (5 mesotheliomas, 10 mesothelial proliferations, 12 pulmonary, and 23 nonpulmonary metastases). The results were evaluated separately, and correlated to the final diagnoses. Concordant results were obtained in 48/50 cases. TTF-1 and Napsin A were positive in 8/12 and 10/12 pulmonary adenocarcinomas, respectively. Both markers were negative in 42 cases, including two lung carcinomas. Napsin reactivity was found in more than 75% of the tumor cells in 9/10 positive cases, whereas TTF-1 reactivity was seen in more than 75% of the tumor cells in 2/8 positive cases only (P < 0.05). This makes napsin A an alternative to TTF-1 in cytological diagnosis of effusions in which tumor cells may be scanty. 相似文献
78.
Bergman A Karlsson P Berggren J Martinsson T Björck K Nilsson S Wahlström J Wallgren A Nordling M 《Genes, chromosomes & cancer》2007,46(3):302-309
The two breast cancer genes BRCA1 and BRCA2 were identified more than 10 years ago and, depending on population, mutations in these genes are responsible for a varying percentage of familial breast cancer. In more than half the families, the increased risk of breast cancer cannot be explained by mutations in these genes, and the goal of this study was to locate novel susceptibility genes. One of the main difficulties in identifying the cause of hereditary non-BRCA1/BRCA2 breast cancer is genetic heterogeneity, possibly due to multiple, incompletely penetrant susceptibility genes, along with ethnic and geographic differences. In this study, one large family and 13 small to medium-sized families with multiple cases of breast cancer were analyzed by genome-wide linkage analysis. The genome scan was performed by genotype analysis of 10,000 SNP markers on microarrays. The strongest evidence of linkage (HLOD 2.34) was obtained on chromosome region 10q23.32-q25.3. A further two regions were identified, with LOD scores above 2.10 on 12q14-q21 and 19p13.3-q12. In a subset of families of western Swedish origin, two regions generated LOD scores exceeding 1.8: 10q23.32-q25.3 and 19q13.12-q13.32. The large family in the study exceeded LOD 1.5 in three regions: 10q23.32-q25.3, 19q13.12-q13.32, and 17p13. Our results indicate that one or more of the suggested regions may harbor genes that are involved in the development of breast cancer. 相似文献
79.
Lindau D Rönnefarth V Erbacher A Rammensee HG Decker P 《European journal of immunology》2011,41(3):669-681
The nucleosome is a major autoantigen known to activate PMN in systemic lupus erythematosus (SLE). TLR9 recognizes bacterial and even mammalian DNA under certain circumstances. Nevertheless, the role of TLR9 in SLE development is still unclear. Since nucleosomes are composed of DNA, we investigated whether TLR9 is required for nucleosome-induced PMN activation. Isolated neutrophils were cultured with nucleosomes, plasma from lupus patients and other stimuli in the presence/absence of various inhibitors. Cells were analyzed by flow cytometry, ELISA and confocal microscopy. We found that nucleosomes circulating in lupus plasma induce the secretion of pro-inflammatory cytokines by PMN. Nucleosomes activate human PMN independently of unmethylated CpG sequences in nucleosomal DNA, leading to IL-8/IL-6/TNF secretion and CD11b up-regulation. Nucleosomes accumulate in the cytoplasm of PMN upon endocytosis, induce TLR9 up-regulation and act synergistically with TLR9 ligands. Nucleosome-induced activation was not inhibited by polymyxin B (PB), chloroquine (CQ), ammonium chloride (AC) or a TLR9 antagonist. Moreover, both PMN isolated from WT and TLR9-KO mice were activated by nucleosomes, as detected by MIP-2 secretion and CD11b up-regulation. Activation occurred therefore independently of endotoxins, endosomal acidification, TLR9 and CpG motifs. TLR9 may thus be differently required in the triggering of nucleosome-induced innate immunity and anti-nucleosome B-cell autoimmunity. 相似文献
80.