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121.

Background

Heart valve surgery outcomes are unknown in middle-income countries and thus cannot be used in health system decision making processes. This study estimated in-hospital mortality and medium and long-term survival.

Methods

This was a retrospective study of 78,806 patients who underwent heart valve surgery between 2001 and 2007 in Brazil. Two national databases were used, the Hospital Information System and the Mortality Information System. Kaplan-Meier survival analysis and log-rank tests were performed. Maximum and median follow-up was 7.7 and 2.8 years, respectively (0.002–7.707).

Results

Valve replacement accounted for 69.1% of procedures performed. Mitral stenosis, the most common valve injury, represented 38.9% of the total. In 94.7% of mitral stenosis patients, aetiology was rheumatic heart disease. In-hospital mortality was 7.6% and was higher for women, for patients who had undergone concomitant coronary artery bypass grafting (CABG) and for the elderly. Overall survival was 69.9% at the end of follow-up. Survival was worst among elderly, male and concomitant CABG patients (P<0.001).

Conclusions

Rheumatic heart disease is still a major public health problem in Brazil. In-hospital mortality and global survival rates of patients who have undergone heart valve surgery were less satisfactory than those reported in high-income countries. The findings of this study can contribute to guiding decision making processes in middle-income countries similar to Brazil and others concerned with improving the quality of care.
  相似文献   
122.
BackgroundPreviously, we demonstrated that OVA-loaded macrophages (OVA-Mφ) partially suppress OVA-induced airway manifestations of asthma in BALB/c mice. In vitro studies showed that OVA-Mφ start to produce IL-10 upon interaction with allergen-specific T cells, which might mediate their immunosuppressive effects. Herein, we examined whether IL-10 is essential for the immunosuppressive effects of OVA-Mφ in vivo, and whether ex vivo stimulation of the IL-10 production by OVA-Mφ could enhance these effects.MethodsPeritoneal Mφ were loaded with OVA and stimulated with LPS or immunostimulatory sequence oligodeoxynucleotide (ISS-ODN) in vitro. The increase of IL-10 production was examined and, subsequently, ex vivo stimulated OVA-Mφ were used to treat (i.v.) OVA-sensitized mice. To further explore whether Mφ-derived IL-10 mediates the immunosuppressive effects, Mφ isolated from IL-10-/- mice were used for treatment.ResultsWe found that stimulation with LPS or ISS-ODN highly increased the IL-10 production by OVA-Mφ (2.5-fold and 4.5-fold increase, respectively). ISS-ODN stimulation of OVA-Mφ significantly potentiated the suppressive effects on allergic airway inflammation. Compared to sham-treatment, ISS-ODN-stimulated OVA-Mφ suppressed the airway eosinophilia by 85% (vs. 30% by unstimulated OVA-Mφ), IL-5 levels in bronchoalveolar lavage fluid by 80% (vs. 50%) and serum OVA-specific IgE levels by 60% (vs. 30%). Importantly, IL-10-/-Mφ that were loaded with OVA and stimulated with ISS-ODN ex vivo, failed to suppress OVA-induced airway inflammation.ConclusionsThese results demonstrate that Mφ-derived IL-10 mediates anti-inflammatory responses in a mouse model of allergic asthma, which both can be potentiated by stimulation with ISS-ODN.  相似文献   
123.
Natural Killer (NK) cell activation is dynamically regulated by numerous activating and inhibitory surface receptors that accumulate at the immune synapse. Quantitative analysis of receptor dynamics has been limited by methodologies that rely on indirect measurements such as fluorescence recovery after photobleaching. Here, we report an apparently novel approach to study how proteins traffic to and from the immune synapse using NK cell receptors tagged with the photoswitchable fluorescent protein tdEosFP, which can be irreversibly photoswitched from a green to red fluorescent state by ultraviolet light. Thus, after a localized switching event, the movement of the photoswitched molecules can be temporally and spatially resolved by monitoring fluorescence in two regions of interest. By comparing images with mathematical models, we evaluated the diffusion coefficient of the receptor KIR2DL1 (0.23 ± 0.06 μm2 s−1) and assessed how synapse formation affects receptor dynamics. Our data conclude that the inhibitory NK cell receptor KIR2DL1 is continually trafficked into the synapse, and remains surprisingly stable there. Unexpectedly, however, in NK cells forming synapses with multiple target cells simultaneously, KIR2DL1 at one synapse can relocate to another synapse. Thus, our results reveal a previously undetected intersynaptic exchange of protein.  相似文献   
124.
Football-related violence (hooliganism) is a global problem. Previous work has proposed that hooliganism is an expression of social maladjustment. Here we test an alternative hypothesis, that hooliganism is typically motivated by a parochial form of prosociality, the evolutionary origins of which may lie in intergroup raiding and warfare. In a survey of Brazilian football fans (N?=?465), results suggest that fan violence is fostered by intense social cohesion (identity fusion) combined with perceptions of chronic outgroup threats. In contrast, maladjustment is unrelated to indices of past acts of football-related violence or endorsement of future violence. Our results suggest that to reduce hooliganism and other forms of inter-group violence, efforts could be made to harness the extreme pro-group sentiments associated with identity fusion in more peaceful ways.  相似文献   
125.
The kinetics of growth and alginate production from glucose in a nitrogen and phosphate-rich medium by Azotobacter vinelandii DSM576 were studied in a laboratory fermenter at pH 7 and 35°C. Batch fermentations were carried out both without control of dissolved oxygen concentration (DO) and at 1, 2, 5 and 10% DO. Although growth was faster at higher DO, maximum biomass concentration was lower. No alginate was produced at 10% DO. Alginate production was faster at 5 and 2% DO but higher alginate concentrations and yields were obtained without DO control. Alginate production was growth-associated at 5% DO, but significant amounts of alginate were produced after growth had stopped at lower DO values. In fermentations without DO control the molecular weight of the polymer reached a maximum (11–17.6 × 104) when specific growth rate was between 0.02 and 0.04 h−1 and residual concentration of ammoniacal nitrogen was between 0.01 and 0.02 g L−1 and then sharply decreased. Received 15 August 1997/ Accepted in revised form 08 January 1998  相似文献   
126.
Summary Studies conducted at the International Rice Research Institute (IRRI) during 1980 and 1981 have shown up to 73% heterosis, 59% heterobeltiosis and 34% standard heterosis for yield in rice. The latter was estimated in comparison to commercial varieties: IR36 and IR42 (yield 4–5 t/ha in wet season trials and 7–8 t/ha in dry season trials). Generally speaking, absolute yield was lower and extent of standard heterosis was higher in wet season than in dry season with some exception. Yields up to 5.9 t/ha (22% standard heterosis) in the wet season and 10.4 t/ha (34% standard heterosis) in the dry season were obtained. Most of the hybrids performed better in some season while some performed better in both seasons. Hybrids showed better lodging resistance although they were 5–10 cm taller. F1 hybrids had significant positive correlations with the parental traits viz., yield (r = 0.446), tillering (r = 0.746), height (r = 0.810) and flowering (r = 0.843). Selection of parents among elite breeding lines on the basis of their per se yield performance, diverse origin and resistance to insects and diseases should give heterotic combination. Yield advantage of hybrids was due primarily to increase in number of spikelets per unit area even though tiller number was reduced. Grain weight was either the same or slightly higher. High yielding hybrids also showed significant heterosis and heterobeltiosis for total dry matter and harvest index. For commercial utilization of heterosis in rice, effective male sterility and fertility restoration systems are available and up to 45% natural outcrossing on male sterile lines has been observed. Consequently, F1 rice hybrid have been successfully developed and used in China. Prospects of developing hybrid rice varieties elsewhere appear bright especially in countries that have organized seed production, certification and distribution programs and where hybrid seed can be produced at a reasonable cost.  相似文献   
127.
Quantitative aspects of reactive gliosis: A review   总被引:27,自引:0,他引:27  
Recent studies of gliosis in a variety of animal models are reviewed. The models include brain injury, neurotoxic damage, genetic diseases and inflammatory demyelination. These studies show that reactive gliosis is not a stereotypic response, but varies widely in duration, degree of hyperplasia, and time course of expression of GFAP immunostaining, content and mRNA. We conclude that there are different biological mechanisms for induction and maintenance of reactive gliosis, which, depending on the kind of tissue damage, result in different expressions of the gliotic response.Special issue dedicated to Dr. Alan N. Davison.  相似文献   
128.
Summary The present study was designed to test whether immunomodulating doses of human beta-interferon would affect the natural cell-mediated cytotoxic function in untreated breast cancer patients or in those subjected to antitumor therapy. Analyses were performed on 11 breast cancer patients, 3 at stage 1 and 8 at stage 2, the latter being subjected to cyclophosphamide, methotrexate, 5-Fluorouracil (CMF) adjuvant chemotherapy. Five patients treated with CMF and 3 patients not subjected to adjuvant chemotherapy, received human beta-interferon (IF, 2×106 IU/patient, i.m.), on days 0,7, and 15 for 6 cycles of 31 days each. The natural killer (NK) activity (NKA) of peripheral blood mononuclear cells (MNC) was tested 24 and 48 h after low-dose IF administration. The results of NKA determinations carried out for the 6 cycles of treatment show that (1) chemotherapy alone depressed NKA; (2) IF alone increased NKA in stage 1 patients not treated with CMF; (3) IF antagonized the depressive activity of CMF on NK function and significantly augumented NKA in the case of low basal cytotoxic activity detectable in MNC collected before IF administration.Parallel in vitro studies showed that the inhibitory effect on NKA provoked by CMF is due to cyclophosphamide present in the association and is effectively antagonized by IF. These data provide rational bases for using IF in immunochemotherapy regimens, when tumor cells are supposed to be susceptible to host control by the natural resistance function.  相似文献   
129.
The deficiency of oleic acid as one of the fatty acids in glucocerebrosides that accumulate (31--77 mg/g dry weight) in the spleen in patients with Gaucher's disease was confirmed in 9 cases. In an effort to account for the 10-fold difference between the oleoyl glycocerebroside content of glucocerebrosides in spleen from controls and patients with Gaucher's disease, we compared the ability of extracts of spleen and fibroblasts from individuals with various forms of Gaucher's disease and controls to hydrolyze [14C]stearoyl and [3H]oleoyl glucocerebroside. The residual glucosylceramidase activity in patients with Gaucher's disease hydrolyzes the glucose moiety of oleoyl glucocerebroside at approximately the same rate as that of stearoyl glucocerebroside. Similarly, the more active glucosylceramidase of control tissue acts upon both oleoyl and stearoyl glucocerebrosides with equal efficiency. These observations indicate that a mutation affecting the substrate specificity of glucosylceramidase cannot account for the lack of oleic acid-containing glucocerebrosides in patients with Gaucher's disease. Thus, the hypothesis that the difference in fatty acid composition found in glucocerebroside is obtained as a result of a mutation affecting the specificity of the residual glucosylceramidase must be rejected.  相似文献   
130.
The objective of this study was to identify possible predisposing factors for candiduria in intensive care unit (ICU) patients from Hospital das Clínicas, Universidade Federal de Goiás, Goiania, Brazil, during one year. Urine samples from 153 ICU patients were obtained by catheterization on admission day and every seven days. Data such as sex, age, antifungal therapy, and variables as antibiotics, underlying diseases or comorbid conditions and stay in the hospital, were collected from patients who had at least one urine culture that yielded > 10(3) yeast colonies/ml. Candiduria was recovered in 68 patients and the commonest predisposing factors were antibiotic therapy (100%) and indwelling urinary catheter (92.6%). The percentage of Candida spp. isolation increased during the extended periods in which patients remained in the ICU. C. albicans was isolated in 69.1%, and the other species non-albicans as C. glabrata, C. kefyr, C. parapsilosis, C. famata, C. guilliermondii, C. krusei, and C. tropicalis were isolated in lower percentage. The high frequency of candiduria and the possible predisposing factors found in ICU patients show that candiduria surveillance should be performed to help reducing nosocomial infections.  相似文献   
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