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61.
Evaluation of Granada agar plate for detection of Streptococcus agalactiae in urine specimens from pregnant women 总被引:1,自引:0,他引:1 下载免费PDF全文
The Granada agar plate (GAP; Biomedics SL, Madrid, Spain) was evaluated for the detection of group B streptococci (GBS) in urine specimens from pregnant women submitted for testing for asymptomatic bacteriuria and was compared with blood agar (BA [Columbia agar with 5% sheep blood]; bioMérieux, Marcy l'Etoile, France). The GAP detected 103 out of 105 GBS, whereas BA detected only 50. Use of the GAP could be a good method for the detection of GBS in urine specimens from pregnant women. 相似文献
62.
We constructed two-dimensional representations of profiles of gene conservation across different genomes using the genome of Escherichia coli as a model. These profiles permit both the visualization at the genome level of different traits in the organism studied and, at the same time, reveal features related to the genomes analyzed (such as defective genomes or genomes that lack a particular system). Conserved genes are not uniformly distributed along the E. coli genome but tend to cluster together. The study of gene distribution patterns across genomes is important for the understanding of how sets of genes seem to be dependent on each other, probably having some functional link. This provides additional evidence that can be used for the elucidation of the function of unannotated genes. Clustering these patterns produces families of genes which can be arranged in a hierarchy of closeness. In this way, functions can be defined at different levels of generality depending on the level of the hierarchy that is studied. The combined study of conservation and phenotypic traits opens up the possibility of defining phenotype/genotype associations, and ultimately inferring the gene or genes responsible for a particular trait. 相似文献
63.
Zalba G San José G Moreno MU Fortuño A Díez J 《Antioxidants & redox signaling》2005,7(9-10):1327-1336
Increased vascular production of reactive oxygen species, especially superoxide anion, significantly contributes to the oxidative stress associated with hypertension. An enhanced superoxide production causes an increased inactivation of nitric oxide that diminishes nitric oxide bioavailability, thus contributing to endothelial dysfunction and hypertrophy of vascular cells. It has been shown that NADPH oxidases play a major role as the most important sources of superoxide anion in phagocytic and vascular cells. Several experimental observations have described an enhanced superoxide generation as a result of NADPH oxidase activation in hypertension. Although these enzymes respond to stimuli such as vasoactive factors, growth factors, and cytokines, recent data suggest a significant role of the genetic background in the modulation of the expression of its different components. Several polymorphisms have been identified in the promoter and in the coding region of CYBA, the gene that encodes the essential subunit of the NADPH oxidase p22phox, some of which seem to influence significantly the activity of these enzymes in the context of cardiovascular diseases. Among CYBA polymorphisms, genetic investigations have provided a novel marker, the -930(A/G) polymorphism, which determines the genetic susceptibility of hypertensive patients to oxidative stress. 相似文献
64.
Gómez-Román JJ Del Valle CE Zarrabeitia MT Martínez JC Goñi FZ Lera RM Cuevas J Val-Bernal JF 《Pathology international》2005,55(9):580-584
Bronchioloalveolar carcinoma is a distinctive subtype of pulmonary adenocarcinoma, without effective therapy, although there have recently been some attempts to use lung transplantation. However, a high post-transplantation local recurrence rate is described with some controversy regarding the possible involved mechanisms, the main possibilities being the lymphatic spread and aerosolization. Presented herein is a case of a bilateral lung transplantation for a bilateral and pneumonic form of non-mucinous bronchioloalveolar carcinoma in a 43-year-old woman. The histological analysis of mediastinal lymph nodes during surgery did not show neoplastic cells. Thirty-five months after transplantation several nodular opacities in donor lungs were detected. Three pulmonary wedge resections were performed showing a non-mucinous bronchioloalveolar carcinoma with the same histological characteristics as the primary. Again, the mediastinal lymph nodes were tumor free. A complete microsatellites molecular analysis was performed to compare the primary and recurrent carcinoma using capillary electrophoresis, showing that the recurrent tumor was generated in a recipient cellular clone. The absence of lymph node metastasis and the molecular evidence of the recipient origin of the neoplasm supports the contamination of the new lungs at the time of implantation as being the reason for the high incidence of recurrence after lung transplantation in this kind of disease. 相似文献
65.
Summary We have analyzed the expression and function of the intron-encoded bI4 maturase when frame-shift mutations in the upstream exon alter the translational process. By constructing secondary cis-acting mutations within the b14 intron, we observed (1) that the bI4 maturase is still translated in the presence of the upstream mutation, albeit in very low amounts, and (2) that the limited amounts of bI4 maturase made under these conditions is no longer able to promote the splicing process of the aI4 intron. These observations, which further strengthen the maturase model, strongly suggest that bI4 maturase acts sequentially on the bI4 intron and then on the aI4 intron. 相似文献
66.
Montano SM Sanchez JL Laguna-Torres A Cuchi P Avila MM Weissenbacher M Serra M Viñoles J Russi JC Aguayo N Galeano AH Gianella A Andrade R Arredondo A Ramirez E Acosta ME Alava A Montoya O Guevara A Manrique H Sanchez JL Lama JR de la Hoz F Sanchez GI Ayala C Pacheco ME Carrion G Chauca G Perez JJ Negrete M Russell KL Bautista CT Olson JG Watts DM Birx DL Carr JK;South American HIV Molecular Surveillance Working Group 《Journal of acquired immune deficiency syndromes (1999)》2005,40(1):57-64
HIV cross-sectional studies were conducted among high-risk populations in 9 countries of South America. Enzyme-linked immunosorbent assay screening and Western blot confirmatory testing were performed, and env heteroduplex mobility assay genotyping and DNA sequencing were performed on a subset of HIV-positive subjects. HIV prevalences were highest among men who have sex with men (MSM; 2.0%-27.8%) and were found to be associated with multiple partners, noninjection drug use (non-IDU), and sexually transmitted infections (STIs). By comparison, much lower prevalences were noted among female commercial sex workers (FCSWs; 0%-6.3%) and were associated mainly with a prior IDU and STI history. Env subtype B predominated among MSM throughout the region (more than 90% of strains), whereas env subtype F predominated among FCSWs in Argentina and male commercial sex workers in Uruguay (more than 50% of strains). A renewed effort in controlling STIs, especially among MSM groups, could significantly lessen the impact of the HIV epidemic in South America. 相似文献
67.
A novel role for shuttling SR proteins in mRNA translation 总被引:15,自引:1,他引:15
68.
Enteroadherent Escherichia coli as a cause of diarrhea among children in Mexico. 总被引:10,自引:7,他引:10 下载免费PDF全文
J J Mathewson R A Oberhelman H L Dupont F Javier de la Cabada E V Garibay 《Journal of clinical microbiology》1987,25(10):1917-1919
Enteropathogenic Escherichia coli (EPEC) often exhibits localized adherence or diffuse adherence to HEp-2 cells. We recently provided evidence that HEp-2 cell-adherent or enteroadherent E. coli (EAEC) not belonging to EPEC serogroups was the cause of diarrhea among U.S. travelers to Mexico. In the present study, we looked for EAEC and EPEC in stool specimens from 154 children with acute diarrhea and 137 well children seen at several outpatient clinics in Guadalajara, Mexico. EAEC showing localized adherence (EAEC-L) was isolated from 13.0% of the patients and 0.7% of the controls (P less than 0.0001). EAEC showing diffuse adherence (EAEC-D) was recovered from 20.8% of the patients and 7.3% of the controls (P less than 0.001). EPEC was isolated from 4.5 and 6.7% of the patients and controls, respectively. Among all enteropathogens, only enterotoxigenic E. coli occurred as commonly (21.4%) as EAEC-D and EAEC-L did in children with diarrhea. Of the EAEC-L strains isolated from children with diarrhea, 20% belonged to recognized EPEC serogroups, and 3.1% of EAEC-D strains belonged to recognized EPEC serogroups. This study suggests that EAEC may be an important pediatric enteropathogen in Mexican children with diarrhea and further supports the observation that adherence to HEp-2 cells may be a marker of virulence independent of EPEC serogroup among E. coli strains. 相似文献
69.
Azorín D Rodríguez-Peralto JL García-García E Salamanca J 《Virchows Archiv : an international journal of pathology》2003,442(3):298-301
Squamous cell carcinoma is one of the most common malignant cutaneous tumors. Several histological variants have been described; the papillary subtype is one of the most infrequent, with only four cases having being reported previously. We report three new cases of this unusual variant of cutaneous squamous cell carcinoma, review the literature and consider the main differential diagnoses. Polymerase chain reaction performed in our three cases did not demonstrate human papilloma virus infection. 相似文献
70.
Javier Domínguez María del Mar Lorenzo Rafael Blasco 《Journal of immunological methods》1998,220(1-2):115-121
We have tested Green Fluorescent Protein (GFP) expressed by a vaccinia virus recombinant as a marker for viral infection. Virus recombinants expressing either wild-type GFP, or a Ser65 to Thr mutated version (GFP-S65T) were used to infect cultured cells, and the appearance of fluorescence was followed during infection by flow cytometry. Although both versions were detectable in infected cells, GFP-S65T gave up to 26-fold brighter fluorescence than wild-type GFP when excited by an argon laser beam (488 nm). In addition, GFP-S65T fluorescence appeared earlier, and infected cells could be detected above background as soon as 1 h after infection. We have used this construct to infect porcine peripheral blood lymphocytes, and show its usefulness to study virus tropism when used in combination with cell-type specific markers. Thus, GFP provides a direct, fast and convenient way to monitor infection by flow cytometry. 相似文献