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21.
In a multicenter study, 407 strains of coryneform bacteria were tested with the updated and extended API (RAPID) Coryne system with database 2.0 (bioMérieux, La-Balme-les-Grottes, France) in order to evaluate the system's capability of identifying these bacteria. The design of the system was exactly the same as for the previous API (RAPID) Coryne strip with database 1.0, i.e., the 20 biochemical reactions covered were identical, but database 2.0 included both more taxa and additional differential tests. Three hundred ninety strains tested belonged to the 49 taxa covered by database 2.0, and 17 strains belonged to taxa not covered. Overall, the system correctly identified 90.5% of the strains belonging to taxa included, with additional tests needed for correct identification for 55.1% of all strains tested. Only 5.6% of all strains were not identified, and 3.8% were misidentified. Identification problems were observed in particular for Corynebacterium coyleae, Propionibacterium acnes, and Aureobacterium spp. The numerical profiles and corresponding identification results for the taxa not covered by the new database 2.0 were also given. In comparison to the results from published previous evaluations of the API (RAPID) Coryne database 1.0, more additional tests had to be performed with version 2.0 in order to completely identify the strains. This was the result of current changes in taxonomy and to provide for organisms described since the appearance of version 1.0. We conclude that the new API (RAPID) Coryne system 2.0 is a useful tool for identifying the diverse group of coryneform bacteria encountered in the routine clinical laboratory.  相似文献   
22.
Mammary gland adenomyoepitheliomas are benign complex mammary gland tumors composed of neoplastic cells of epithelial and myoepithelial origins, described in many species (humans, dogs, cats, rats) and rarely in mice. We report here an adenomyoepithelioma in a C57BL/6 female mouse. Histologically, tubes and cords formed by neoplastic epithelial cells were separated by bundles of neoplastic myoepithelial cells in a clear and partially mucinous matrix. The tumor displayed characteristics of a benign neoplastic proliferation with a compressive growth pattern, and moderate cellular pleomorphism and mitotic index. At immunohistochemistry, the epithelial cells were strongly cytokeratin positive; the myoepithelial cells were weakly cytokeratin positive and strongly smooth muscle actin positive. This is to our knowledge, the first report of a mammary gland adenomyoepithelioma in a C57BL/6 mouse.  相似文献   
23.
The genetic diversity of two samples of Cestoda (Bothriocephalus funiculus, Renaud and Gabrion, 1984) parasitizing two sympatric teleostean species was assessed using random amplified polymorphic DNA (RAPD). A total of 72Bothriocephalus were analyzed individually, and electrophoretic analysis of the amplification products of 65 primers among the 68 tested revealed monomorphic patterns, reflecting the close genetic relatedness within and between the parasites of the two samples. However, 3 primers showed polymorphic patterns at 6 RAPD sites. Analysis of the distribution of these genomic fragments, assuming random mating, showed strong linkage disequilibria (only 8 genetic combinations were observed among the 32 expected). Two genetic entities displaying a high degree of host specificity were evidence within our two samples ofB. funiculus. This powerful molecular technique can be used as a diagnostic tool in studies concerning the biodiversity of related genetic entities and could have broad applications in parasitology.  相似文献   
24.
In a double-blind, randomized, and placebo-controlled previous trial, the efficacy of Vi-rEPA for typhoid fever in 2- to 5-year-olds was 89.0% for 46 months. Vi-rEPA contained 25 microg of Vi and induced a greater-than-eightfold rise in immunoglobulin G (IgG) anti-Vi in all of the vaccinees tested. In this investigation, we conducted a dosage-immunogenicity study of 5, 12.5, and 25 microg of Vi-rEPA in this age group. Two doses of Vi-rEPA were injected 6 weeks apart. Blood samples were taken before and at 10 weeks (4 weeks after the second injection) and 1 year later. All postimmunization geometric mean (GM) levels were higher than the preimmune levels (P < 0.0001). At 10 weeks, the GM IgG anti-Vi level elicited by 25 microg (102 EU/ml) was higher than those elicited by 12.5 microg (74.7 EU/ml) and 5 microg (43 EU/ml) (P < 0.004): all of the children had > or = 3.52 EU/ml (estimated minimum protective level). One year later, the levels declined about sevenfold (13.3 and 11.3 versus 6.43 EU/ml, P < 0.0001) but remained significantly higher than the preimmune levels (P < 0.0001), and >96% of the children had a greater-than-eightfold rise. This study also confirmed the safety and consistent immunogenicity of the four lots of Vi-rEPA used in this and previous trials.  相似文献   
25.
Subpopulations of lymphoid cells were compared with respect to their ability to migrate into peripheral lymphoid organs of nonobese diabetic (NOD) mice and various strains of control mice. In short-term, in vivo homing studies, no major differences in the pattern of homing of B and T cells were observed among all mouse strains studied. On the other hand, CD4 cells localized consistently more efficiently than CD8 cells in both PP and LN of adult NOD and BALB/c mice, whereas both populations migrated roughly equivalently in LN of adult DBA/2, CBA, and C57BL/6 mice. No age-dependent differences in the homing of CD4 and CD8 cells were observed in BALB/c mice. On the contrary, in 2-week-old NOD mice, CD4 and CD8 cells migrated equally well. The preferential entry of CD4 cells in adult NOD and BALB/c did not result from increased blood transit time of CD8 cells. On the other hand, the preferential migration of CD8 cells was observed in the liver, whereas the two T-cell subsets migrated equally well in the lungs. The differences in the homing characteristics of CD4 and CD8 cells among NOD, BALB/c, and C57BL/6 mice were not related to modifications in the level of expression of adhesion molecules such as MEL-14, LFA-1, and Pgp-1.  相似文献   
26.
A novel naturally occurring antiangiogenic agent isolated from cartilage, referred to as Neovastat (AE-941), was examined for its efficacy against tumor neovascularization and progression. Exposure to Neovastat results in ex ovo antiangiogenic properties in the chorioallantoid membrane of chicken embryo (71% decrease in the angiogenic index as compared to the basic fibroblast growth factor (bFGF) treated control embryos, P < 0.0001). Oral administration of Neovastat inhibits bFGF-induced angiogenesis in the Matrigel mouse model (87.5% decrease in hemoglobin as compared to the bFGF-treated control implants, P < 0.0001). Neovastat also induces a dose response decrease of lung metastases in the Lewis lung carcinoma model (oral administration; 69.1% of inhibition obtained at the maximal dose of 0.5 ml/day, P < 0.0001). Combined with a sub-optimal dose of cisplatinum (2 mg/kg, i.p.), Neovastat (0.5 ml/day) improved the therapeutic index by increasing the antimetastatic efficacy and by exerting a protective activity against cisplatinum-induced body weight loss and myelosuppression. In summary, our experimental data provide evidence of antiangiogenic and antimetastatic properties of Neovastat, following oral administration.  相似文献   
27.
28.
Two patients with Ph-positive chronic myelocytic leukemia in erythroblastic transformation and rearrangement of the short arm of chromosome 18 are reported. Fluorescence in situ hybridization studies showed that the 18p rearrangement resulted from translocation of the main part of chromosome 22 long arm to 18p, including BCR-ABL1 fusion. The 18p abnormality resulted, thus, in loss of 18p and duplication of BCR-ABL1 in both patients. The possible relation to the erythroblastic type of blastic phase is briefly discussed. In addition an apparently intact germline ABL1 gene was duplicated and inserted into chromosome 6 at band p21 in one of these patients.  相似文献   
29.
Peroxisome proliferator-activated receptors (PPARs) are nuclear hormone receptors, initially described as molecular targets for synthetic compounds that induce peroxisome proliferation. PPARgamma is the best characterized of the PPARs. The heterodimer of PPARgamma with the retinoid X receptor (RXR) plays a crucial role in adipogenesis and insulin sensitization. The RXR/PPARgamma heterodimer furthermore has been reported to have important immunomodulatory activities and to affect cell proliferation/differentiation pathways in various malignancies. PPARgamma is activated by a number of naturally occurring fatty acid derivatives and by several synthetic compounds, including the thiazolidinediones and L-tyrosine-based insulin sensitizers. This review gives an overview of the pleiotropic functions of PPARgamma and discusses the wide-ranging medical implications that modulation of PPARgamma activity might have for various diseases, ranging from obesity and type 2 diabetes to cancer and inflammation.  相似文献   
30.
The aim of this study was to determine, by transmission electron microscopy, the differentiation features of 21 human malignant mesothelioma cell lines (HMCLs) established from 13 specimens of 12 confirmed human malignant mesotheliomas, and of tumours induced in nude mice injected with 16 HMCLs. Fifty per cent of HMCLs showed typical mesothelial differentiation (long and slender microvilli, desmosomes, perinuclear intermediate filaments); 29 per cent did not show differentiation; and the remainder were poorly differentiated. Three human tumour specimens gave several different HMCLs; the cell lines obtained from a given tumour exhibited variable mesothelial differentiation. Eleven HMCLs were compared with the native tumour. Four were similar to the tumour and seven were less well differentiated, in most cases in relation to their microvilli. With six HMCLs, tumours induced in nude mice were less well differentiated than the corresponding cell lines, whereas with four HMCLs, tumours were equally or better differentiated. However, in most nude mice tumours, typical mesothelial microvilli were present. These results show that cell lines established from malignant mesothelioma may exhibit dedifferentiated features. However, while the variability in ultrastructural differentiation may result from the culture microenvironment, it could also be related to the state of differentiation, of the native tumour sample and to tumour cell heterogeneity.  相似文献   
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