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81.
The performance of two DNA line probe assays, a new version of INNO-LiPA Mycobacteria (Innogenetics, Ghent, Belgium) and the GenoType Mycobacterium (Hain Diagnostika, Nehren, Germany), were evaluated for identification of mycobacterial species isolated from liquid cultures. Both tests are based on a PCR technique and designed for simultaneous identification of different mycobacterial species by reverse hybridization and line probe technology. The INNO-LiPA Mycobacteria v2 targeting the 16S-23S rRNA gene spacer region was developed for the simultaneous identification of 16 different mycobacterial species. The GenoType Mycobacterium, which targets the 23S rRNA gene, allows simultaneous identification of 13 mycobacterial species. Both tests were evaluated on 110 mycobacterial strains belonging to 22 different mycobacterial species (20 reference strains, 83 clinical strains, and 4 Mycobacterium kansasii strains isolated from tap water) that were previously inoculated into MB/BacT bottles. The sensitivity of both methods, defined as the number of positive results obtained with the Mycobacterium genus probe together with an interpretable result on the number of samples tested was 110 of 110 (100%) for INNO-LiPA and 102 of 110 (92.7%) for GenoType. For samples with interpretable results, INNO-LiPA was able to correctly identify 109 of 110 samples (99.1%), whereas the GenoType correctly identified 100 of 102 samples (98.0%). Both tests were easy to perform, rapid, and reliable when applied to mycobacterial identification directly from MB/BacT bottles.  相似文献   
82.
The FHIT gene, located at human chromosome 3p14.2, is frequently deleted in a number of human cancers, and interstitial deletions at this site were recently described in a significant proportion (41%) of testicular germ cell tumors. We studied the expression of Fhit protein in the progression and differentiation of testicular germ cell tumors to further elucidate its role in this type of malignancy. Forty-five patients with testicular germ cell tumors and intratubular germ cell neoplasia (identified in 42/45 cases) were included in the study. Immunohistochemical staining with polyclonal rabbit IgG antibody to Fhit (ZR44, Zymed Laboratories) on formalin-fixed, paraffin-embedded tissues was used. Fhit was constitutively expressed in germ cells, Sertoli cells, and Leydig cells. All 42 cases of intratubular germ cell neoplasia revealed no expression of this protein. No expression of Fhit was observed in any case of pure seminoma or in the seminomatous component of mixed germ cell tumors. Unexpectedly, Fhit expression was frequently (16/18) observed in the glandular tissue of mature teratomatous component of mixed germ cell tumors, despite the absence of Fhit in the intratubular germ cell neoplasia, the presumed precursor lesion. The loss of Fhit expression is a consistent characteristic of intratubular germ cell neoplasia, which suggests a potential role in a maturation/differentiation defect early in the development of testicular germ cell tumors. Likewise, the lack of expression in seminomas is supportive of this view. However, re-expression of Fhit in well-differentiated glandular epithelium of teratomatous component of mixed germ cell tumors suggests that there is no loss of FHIT gene in this subset of neoplasia but rather that Fhit protein expression is differently regulated through the phases of germ cell tumor progression.  相似文献   
83.
Background: The exposure of human neutrophils to uniform concentrations of chemoattractants, such as N-formyl peptides, induces morphological cell polarization. In this study we report the temporal sequence of changes in cell shape, F-actin, and cell surface morphology during cellular polarization induced by N-formylmethionyl-leucyl-phenyl-alanine (fMLP) in human neutrophils in suspension. Methods: Neutrophil shape changes induced by 10?8 M fMLP were observed with DIC microscopy. Size and Cellular granularity were analyzed by flow cytometry measuring their forward and side scattered light. To visualize F-actin distribution, neutrophils were labeled with the fluorescence probe FITC-phalloidin, and were examined with fluorescence and confocal laser scanning microscopy. Cell surface morphology was assessed with scanning electron microscopy (SEM). Results: The stimulation of round-smooth neutrophils with nanomolar concentrations (10?8 M) of fMLP in suspension induced a temporal sequence of morphological changes during cell polarization, characterized by 1) increase in size as determined by forward angle scattered light, 2) rapid redistribution of F-actin from a diffuse cytoplasmic localization to the cell periphery, and 3) rapid reorganization of cell surface morphological features, with accumulation of plasma membrane in the front of polar cells. Four cell shapes were identified with SEM after stimulation of round-smooth neutrophils: round-ridged, round-ruffled, nonpolar ruffled, and polar cells. These cell shapes were correlated with a cortical localization, focal aggregates, and multipolar distribution of F-actin. In polar neutrophils, F-actin became concentrated in the front of the cell. Conclusions: These findings show the relation between reorganization of the microfilamentous cytoskeleton and modifications in cell shape and surface features during cell polarization induced after fMLP activation in neutrophils. This approach offers a powerful tool for further analysis of receptor distribution in polarized, motile neutrophils. © 1995 Wiley-Liss, Inc.  相似文献   
84.
The powerful genetic polymorphism of the HLA system has been used to identify individuals and populations. Ethnic groups may be characterized by specific HLA allele frequencies and particular extended HLA haplotypes; also, genetic relationships among these groups may be deduced. In the present study, serology and DNA typing were used to detect HLA-A, -B, -C, -DR, and -DQ alleles in each individual and to calculae characteristic haplotypes in Algerians. These results were compared to those previously obtained in other populations, particularly northern Mediterraneans; genetic distances and their respective dendrograms place Basques and Spaniards closer to Algerians than to other Europeans. Also, characteristic Basque and/or Spanish haplotypes are found in Algerians; i.e., A30-B18-Cw3-DR3-DQ2 and Al-B57-Ctv7-DR7-DQ2. This supports the evidence that the Algerian population, mainly its paleo-North African component (Berbers), has a common descent with Basques and Spaniards, probably reflecting a preneolithic relationship between Iberians and paleo-North Africans.  相似文献   
85.
Mutations in Bruton’s tyrosine kinase (BTK) gene result in X linked agammaglobulinemia (XLA). Using Single Strand Conformation Polymorphism (SSCP) followed by direct sequencing 21 mutations were found in 27 patients with an XLA phenotype from 21 unrelated families. We identified 13 novel and 8 known mutations: seven missense (R288W, R544G, P566S, K430E; K374N, L512P, R544S), 5 nonsense (Q196X, Y361X, L249X, Q612X, Q466X), 2 deletions of one nucleotide (A207fsX216, Q612fsX648), 2 deletion‐insertions (V219fsX227, K218fsX228), one insertion of two nucleotides (S572fsX587) and 4 point mutations in donor/acceptor splice sites (g.IVS1+1G>C, g.IVS6+5G>A, g.IVS10+1G>T, g.IVS13‐1GG>CT). Carrier detection was performed in 18 mothers. Only in one case the mutation was found to be de novo. Additionally, BTK mutations were not found in four patients without family history, but with XLA‐compatible phenotype. Hum Mutat 18:84, 2001. © 2001 Wiley‐Liss, Inc.  相似文献   
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Probiotics and immune response   总被引:1,自引:0,他引:1  
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Co-infection by human immunodeficiency virus and hepatitis B and C viruses is quite common because they share similar routes of transmission. The introduction of highly active antiretroviral therapy has significantly improved the life expectancy of HIV-infected patients in the last few years. However, chronic viral hepatitis represents an emerging cause of morbidity and mortality in this population, either as a result of end-stage liver disease or as a consequence of hepatotoxicity induced by antiretroviral drugs. The main goal of the Consensus Conference was to establish specific recommendations for the management of chronic viral hepatitis B and C in HIV-infected patients. The role of orthotopic liver transplantation for co-infected individuals with end-stage liver disease was also assessed.  相似文献   
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