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21.
Ischemic stroke occurs in 0.2-0.4% of patients undergoing left heart catheterization, and is responsible for 5-10% of the mortality associated with the procedure. The main predisposing factors for this complication are female gender, complex atherosclerotic plaques in the ascending aorta, and peripheral arterial disease. The possibility of timely intervention with reperfusion therapy supports close clinical monitoring during the immediate post-catheterization period. The cardiologist should be familiar with the various types of stroke reperfusion therapy and its indications according to the time interval between catheterization and the stroke. The decision should be discussed with neurology and neuroradiology.  相似文献   
22.
Ninety-four Olmsted County, Minnesota residents with temporal arteritis (TA) initially diagnosed between 1950 and 1985 (incidence cohort) were identified. The age- and sex-adjusted incidence of TA per 100,000 population age 50 years or older was 17.0 (95% confidence interval [CI] 13.6-20.5), with a marked increase in incidence with age and a threefold greater incidence in women (23.4, 95% CI 18.2-28.7) than in men (7.4, 95% CI 3.7-11.0). The previously described secular increase in TA incidence in Olmsted County women continued from 1970 through 1985, while TA incidence in men declined in this latter time period. Although the frequency of classic clinical manifestations of TA declined over time, the percentage of patients undergoing biopsy who have positive specimens remained relatively constant (women 41%, men 26%). The incidence rate of temporal artery biopsy also increased for women during this period, but declined for men, suggesting that the differing trends in TA incidence by sex may be partially attributable to a detection bias. Future research in TA etiology and epidemiology should focus on possible causal factors linked to the differential TA incidence by sex.  相似文献   
23.
The apparently dormant breast cancer micrometastases in haemopoietic marrow are correlated with distant metastatic carcinoma dissemination. We studied in vitro interactions of carcinoma cells with adjacent stromata, using connective tissue cell cultures from breast and bone marrow samples of normal donors, comparing them to the pericancerous breast tissue and bone marrows of 12 selected patients with invasive breast carcinomas. Cancer cells were detected by immunocytochemistry and RT-PCR in all the bone marrows and in most blood samples of the studied patients. We monitored the growth and interaction of carcinoma MCF-7 cells with the stromata. The normal breast stroma sustained typical massive cancer growth. The pericancerous breast stroma induced the invasive mesenchymal pattern of growth. Normal bone marrow stroma induced the same conversion and was highly adhesive, retaining the cells in the stroma, but carcinoma patients' bone marrow stromata underwent low adhesive interactions with cancer cells, releasing them potentially into the circulation. The semi-quantitative RT-PCR indicated an enhanced expression of the hepatocyte growth factor and its receptor c-met in breast and bone marrow stromata of cancer patients. The input of cancer cells into the normal bone marrow may induce modifications of the local microenvironment, favourable for growth and release of carcinoma cells into the systemic circulation, which correlate with the poor prognosis of patients with bone marrow micrometastases. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
24.
In Corte de Pedra (CP), northeastern Brazil, Leishmania braziliensis causes three distinct forms of American tegumentary leishmaniasis (ATL). To test the hypothesis that strain polymorphism may be involved in this disease spectrum and accurately characterize the parasite population structure in CP, we compared one L. major, two non-CP L. braziliensis, one CP L. amazonensis, and 45 CP L. braziliensis isolates, obtained over a 10-year period from localized cutaneous, mucosal, and disseminated leishmaniasis patients, with randomly amplified polymorphic DNA (RAPD). Electrophoretic profiles were mostly unique across species. All typing protocols revealed polymorphism among the 45 CP L. braziliensis isolates, which displayed eight different RAPD patterns and greater than 80% overall fingerprint identity, attesting to the adequacy of the tools to assess strain variability in CP's geographically limited population of parasites. The dendrogram based on the sum of RAPD profiles of each isolate unveiled nine discrete typing units clustered into five clades. Global positioning showed extensive overlap of these clades in CP, precluding geographic sequestration as the mechanism of the observed structuralization. Finally, all forms of ATL presented a statistically significant difference in their frequencies among the clades, suggesting that L. braziliensis genotypes may be accompanied by specific disease manifestation after infection.  相似文献   
25.
Hematopoietic stem cell transplant recipients lose immune memory of exposure to infectious agents and vaccines accumulated through a lifetime, and therefore need to be revaccinated. Reimmunization protocols vary greatly among hematopoietic stem cell transplant centers. Diphtheria and tetanus toxoids, pertussis vaccine, Haemophilus influenza type B conjugate, 23-valent pneumococcal polysaccharide, inactivated influenza and polio vaccine and live attenuated measles-mumps-rubella vaccine are the currently recommended vaccines to be included in a vaccination program after hematopoietic stem cell transplant. Other variables, such as stem cell source, new adjuvants, T-cell depleted transplants, nonmyeloablative conditioning and donor immunization have recently been introduced and a constant update of current recommendations are needed. Studies recently published, the use of other vaccines and the perspectives for different vaccination protocols are discussed in this review.  相似文献   
26.
The immunological basis for the production of autoantibodies characteristic of systemic lupus erythematosus (SLE) against a wide range of antigens remains obscure. The specificity of (NZB x NZW)F1 (BWF1) or MRL/Mp-lpr/lpr (MRL/lpr) mouse monoclonal antibodies (mAb) was examined by immunofluorescence, immunoblotting and immunoprecipitation techniques. Using non-synchronized HEp-2 cells as substrate, the murine mAb were classified by indirect immunofluorescence into five groups on the basis of their staining patterns of subcellular components in interphase and mitotic stages of the cell cycle. The nature of the antigens recognized by the murine lupus was assessed by immunoblotting experiments in total, cytoplasmic and nuclear cell extracts from HEp-2 cells. The six antibodies used recognized in total cell extracts a range of polypeptides with apparent molecular weights from 25,000 to 210,000. Three polypeptides of 130,000, 110,000 and 45,000 MW were recognized by all six antibodies in both nuclear and cytoplasmic extracts. Immunoprecipitation of total cellular extracts labelled with [35S]methionine showed almost the same pattern as obtained in the immunoblotting assay. The labelling in vivo of HEp-2 cells with [32P], followed by the immunoprecipitation of the [32P]cell lysate showed that these mAb recognized phosphorylated proteins. The progressive decrease in reactivity of these mAb following treatment with higher concentrations of alkaline phosphatase in both [32P]cell lysate or nitrocellulose membranes indicates that these mAb recognize phosphorylated epitopes.  相似文献   
27.
The present experiment aimed at investigating electrophysiologic changes observed as beta band asymmetry, by Quantitative Electroencephalography (qEEG), when individuals performed a reaching motor task (catching a ball in free fall). The sample was composed of 23 healthy individuals, of both sexes, with ages varying between 25 and 40 years old. All the subjects were right handed. A two-way ANOVA was applied for the statistical analysis, to verify the interaction between task moment (i.e., 2 s before and 2 s after ball's fall) and electrode (i.e., frontal, central and temporal regions). The first analysis compared electrodes placed over the somatosensory cortex. Central sites (C3–C4) were compared with temporal regions (T3–T4). The results showed a main effect for moment and position. The second analysis was focused over the premotor cortex, which was represented by the electrodes placed on the frontal sites (F3–F4 versus F7–F8), and a main effect was observed for position. Taken together, these results show a pattern of asymmetry in the somatosensory cortex, associated with a preparatory mechanism when individuals have to catch an object during free fall. With respect to task moment, after the ball's fall, the asymmetry was reduced. Moreover, the difference in asymmetry between the observed regions were related to a supposed specialization of areas (i.e., temporal and central). The temporal region was associated with cognitive processes involved in the motor action (i.e., explicit knowledge). On the other hand, the central sites were related to the motor control mechanisms per se (i.e., implicit knowledge). The premotor cortex, represented by two frontal regions (i.e., F3–F4 versus F7–F8), showed a decrease on neural activity in the contralateral hemisphere (i.e., to the right hand). This result is in agreement with other experiments suggesting a participation of the frontal cortex in the planning of the apprehension task. This sensorimotor paradigm may contribute to the repertoire of tasks used to study clinical conditions such as depression, alzheimer and Parkinson diseases.  相似文献   
28.
In order to determine the prevalence and risk factors for Chlamydia trachomatis infection in adolescent females and young women in central Brazil, 296 subjects attending two public health services were evaluated. The overall prevalence of C. trachomatis infection, as determined using polymerase chain reaction, was 19.6% (95% confidence interval [CI], 15.3–24.7). In multivariate analysis, young age (odds ratio [OR]adjusted 2.32, 95%CI 1.1–4.8, p<0.05) and having 2–3 (ORadjusted 3.41, 95%CI 1.6–6.3, p<0.05) or ≥4 sexual partners in life (ORadjusted 3.10, 95%CI 1.1–6.3, p<0.05) were factors significantly associated with chlamydial infection. In conclusion, the prevalence of C. trachomatis infection was high in the studied population and risk factors were related to age and sexual behavior.  相似文献   
29.
In Hereditary Diffuse Gastric Cancer syndrome, E-cadherin germline mutations of the missense type harbour significant functional consequences. In this study, we have characterised the effect of T340A, A617T, A634V and V832M E-cadherin germline missense mutations on cell morphology, motility and proliferation. Wild-type E-cadherin and A617T expressing cells have an epithelial-like morphology, with polarised cells migrating unidirectionally. T340A and A634V expressing cells, fibroblast-like, have a high motile phenotype. We show that this phenotype is dependent on an increased level of active RhoA. V832M expressing cells grow in piled-up structure of round cells, as an effect of the disturbance of the binding between alpha-catenin and beta-catenin. The destabilisation of the adhesion complex is shown to hamper the motile capabilities of these cells. We did not observe any effect of the E-cadherin mutations on cell proliferation. We show the existence of a genotype-phenotype correlation between different E-cadherin mutations and cell behaviour. However, we demonstrate that the ability of cells expressing the different E-cadherin mutations to invade is independent on their motile capabilities, providing evidence that motility is neither necessary nor sufficient for cells to invade. Our data give new insights into the understanding of the mechanisms linking invasion and E-cadherin mutations in diffuse gastric cancer.  相似文献   
30.
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