1000 resultados para 897.541
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PURPOSE: To investigate the involvement of the cornea during endotoxin-induced uveitis (EIU) in the rat and the effect of Ngamma-nitro-L-arginine methyl ester (L-NAME) as nitric oxide synthase (NOS) inhibitor, administered by iontophoresis. METHODS: EIU was induced in Lewis rats that were killed at 8 and 16 hours after lipopolysaccharide (LPS) injection. The severity of uveitis was evaluated clinically at 16 hours, and nitrite levels were evaluated in the aqueous humor at 8 hours. Corneal thickness was measured, 16 hours after LPS injection, on histologic sections using an image analyzer. Transmission electron microscopy (TEM) was used for fine analysis of the cornea. Transcorneoscleral iontophoresis of L-NAME (100 mM) was performed either at LPS injection or at 1 and 2 hours after LPS injection. RESULTS: At 16 hours after LPS injection, mean corneal thickness was 153.7+/-5.58 microm in the group of rats injected with LPS (n=8) compared with 126.89+/-11.11 microm in the saline-injected rats (n=8) (P < 0.01). TEM showed stromal edema and signs of damage in the endothelial and epithelial layers. In the group of rats treated by three successive iontophoreses of L-NAME (n=8), corneal thickness was 125.24+/-10.36 microm compared with 146.76+/-7.52 microm in the group of rats treated with iontophoresis of saline (n=8), (P=0.015). TEM observation showed a reduction of stromal edema and a normal endothelium. Nitrite levels in the aqueous humor were significantly reduced at 8 hours by L-NAME treatment (P=0.03). No effect on corneal edema was observed after a single iontophoresis of L-NAME at LPS injection (P=0.19). Iontophoresis of saline by itself induced no change in corneal thickness nor in TEM structure analysis compared with normal rats. CONCLUSIONS: Corneal edema is observed during EIU. This edema is significantly reduced by three successive iontophoreses of L-NAME, which partially inhibited the inflammation. A role of nitric oxide in the corneal endothelium functions may explain the antiedematous effect of L-NAME.
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PURPOSE: The aim of the study was to determine whether glucose uptake in viable myocardium of ischemic cardiomyopathy patients depends on rest myocardial blood flow (MBF) and the residual myocardial flow reserve (MFR). METHODS: Thirty-six patients with ischemic cardiomyopathy (left ventricular ejection fraction 25 ± 10 %) were studied with N-ammonia and F-fluorodeoxyglucose (FDG) positron emission tomography (PET). Twenty age-matched normals served as controls. Regional MBF was determined at rest and during dipyridamole hyperemia and regional FDG extraction was estimated from regional FDG to N-ammonia activity ratios. RESULTS: Rest MBF was reduced in viable (0.42 ± 0.18 ml/min per g) and nonviable regions (0.32 ± 0.09 ml/min per g) relative to remote regions (0.68 ± 0.23 ml/min per g, p < 0.001) and to normals (0.63 ± 0.13 ml/min per g). Dipyridamole raised MBFs in controls, remote, viable, and nonviable regions. MBFs at rest (p < 0.05) and stress (p < 0.05) in viable regions were significantly higher than that in nonviable regions, while MFRs did not differ significantly (p > 0.05). Compared to MFR in remote myocardium, MFRs in viable regions were similar (1.39 ± 0.56 vs 1.70 ± 0.45, p > 0.05) but were significantly lower in nonviable regions (1.23 ± 0.43, p < 0.001). Moreover, the FDG and thus glucose extraction was higher in viable than in remote (1.40 ± 0.14 vs 0.90 ± 0.20, p < 0.001) and in nonviable regions (1.13 ± 0.21, p < 0.001). The extraction of FDG in viable regions was independent of rest MBF but correlated inversely with MFRs (r =-0.424, p < 0.05). No correlation between the FDG extraction and MFR was observed in nonviable regions. CONCLUSION: As in the animal model, decreasing MFRs in viable myocardium are associated with increasing glucose extraction that likely reflects a metabolic adaptation of remodeling hibernating myocytes.
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BACKGROUND: Many factors affect survival in haemodialysis (HD) patients. Our aim was to study whether quality of clinical care may affect survival in this population, when adjusted for demographic characteristics and co-morbidities. METHODS: We studied survival in 553 patients treated by chronic HD during March 2001 in 21 dialysis facilities in western Switzerland. Indicators of quality of care were established for anaemia control, calcium and phosphate product, serum albumin, pre-dialysis blood pressure (BP), type of vascular access and dialysis adequacy (spKt/V) and their baseline values were related to 3-year survival. The modified Charlson co-morbidity index (including age) and transplantation status were also considered as a predictor of survival. RESULTS: Three-year survival was obtained for 96% of the patients; 39% (211/541) of these patients had died. The 3-year survival was 50, 62 and 69%, respectively, in patients who had 0-2, 3 and >or=4 fulfilled indicators of quality of care (test for linear trend, P < 0.001). In a Cox multivariate analysis model, the absence of transplantation, a higher modified Charlson's score, decreased fulfilment of indicators of good clinical care and low pre-dialysis systolic BP were independent predictors of death. CONCLUSION: Good clinical care improves survival in HD patients, even after adjustment for availability of transplantation and co-morbidities.
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We have developed a technetium labeling technology based on a new organometallic chemistry, which involves simple mixing of the novel reagent, a 99m Tc(I)-carbonyl compound, with a His-tagged recombinant protein. This method obviates the labeling of unpaired engineered cysteines, which frequently create problems in large-scale expression and storage of disulfide-containing proteins. In this study, we labeled antibody single-chain Fv fragments to high specific activities (90 mCi/mg), and the label was very stable to serum and all other challenges tested. The pharmacokinetic characteristics were indistinguishable from iodinated scFv fragments, and thus scFV fragments labeled by the new method will be suitable for biodistribution studies. This novel labeling method should be applicable not only to diagnostic imaging with 99mTc, but also to radioimmunotherapy approaches with 186/188 Re, and its use can be easily extended to almost any recombinant protein or synthetic peptide.
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Microtubule-associated protein 1B, MAP1B, is one of the major growth associated and cytoskeletal proteins in neuronal and glial cells. It is present as a full length protein or may be fragmented into a heavy chain and a light chain. It is essential to stabilize microtubules during the elongation of dendrites and neurites and is involved in the dynamics of morphological structures such as microtubules, microfilaments and growth cones. MAP1B function is modulated by phosphorylation and influences microtubule stability, microfilaments and growth cone motility. Considering its large size, several interactions with a variety of other proteins have been reported and there is increasing evidence that MAP1B plays a crucial role in the stability of the cytoskeleton and may have other cellular functions. Here we review molecular and functional aspects of this protein, evoke its role as a scaffold protein and have a look at several pathologies where the protein may be involved.
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OBJECTIVES: To determine the risk of hospital readmission, nursing home admission, and death, as well as health services utilization over a 6-month follow-up, in community-dwelling elderly persons hospitalized after a noninjurious fall. DESIGN: Prospective cohort study with 6-month follow-up. SETTING: Swiss academic medical center. PARTICIPANTS: Six hundred ninety persons aged 75 and older hospitalized through the emergency department. MEASUREMENTS: Data on demographics and medical, physical, social, and mental status were collected upon admission. Follow-up data were collected from the state centralized billing system (hospital and nursing home admission) and proxies (death). RESULTS: Seventy patients (10%) were hospitalized after a noninjurious fall. Fallers had shorter hospital stays (median 4 vs 8 days, P<.001) and were more frequently discharged to rehabilitation or respite care than nonfallers. During follow-up, fallers were more likely to be institutionalized (adjusted hazard ratio=1.82, 95% confidence interval=1.03-3.19, P=.04) independent of comorbidity and functional and mental status. Overall institutional costs (averaged per day of follow-up) were similar for both groups ($138.5 vs $148.7, P=.66), but fallers had lower hospital costs and significantly higher rehabilitation and long-term care costs ($55.5 vs $24.1, P<.001), even after adjustment for comorbidity, living situation, and functional and cognitive status. CONCLUSION: Elderly patients hospitalized after a noninjurious fall were twice as likely to be institutionalized as those admitted for other medical conditions and had higher intermediate and long-term care services utilization during follow-up, independent of functional and health status. These results provide direction for interventions needed to delay or prevent institutionalization and reduce subsequent costs.
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Oxygen consumption of collagenase-liberated rat adipocytes was measured by two different techniques: a microspectrophotometric method using hemoglobin as indicator of respiration and a technique using the oxygen electrode. These two completely different techniques gave similar values for oxygen consumption. With the spectrophotometric method, the oxygen consumption of single fat cells was determined. A close positive correlation (r = greater than 0.90) between oxygen consumption and fat cell size was observed in each tissue examined. With the oxygen electrode technique, oxygen consumption of adipocyte suspensions from young (40 days, 180 g) and old (90 days, 480 g) rats was examined. Fat cells of the suspensions were separated into classes of different size by a flotation technique. A significant positive correlation between fat cell size and oxygen consumption was observed in both young (r = 0.88) and old (r = 0.95) rats. However, the slope was much steeper in young rats. At a cell weight of 0.1 microgram the oxygen consumption was 0.364 and 0.086 microL O2/10(6) cells/min-1 in young and old rats, respectively. In the literature, a number of separate metabolic pathways have been found to be related positively to fat cell size and negatively to age. We conclude that these scattered metabolic observations are in agreement with integrated data on energy expenditure as evaluated from oxygen consumption. Estimations of the energy expenditure of adipose tissue indicates that this tissue is responsible for about 1% and 0.5% of the total energy expenditure in young and old rats, respectively.
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At mucosal surfaces, we must co-exist with a high density of diverse microorganisms; therefore, protection against these occurs on multiple levels. Leukocyte- and epithelial derived-antimicrobial peptides and proteins (AMPs) comprise an essential component of immune defense. These molecules possess antibacterial, antifungal and signalling properties and probably contribute to defence and maintenance of homeostasis between the host and commensal microorganisms. Among these AMPs is bactericidal/permeability-increasing protein (BPI), an antimicrobial protein with potent endotoxin-neutralising activity, and several homologs. This review explores the roles of BPI and and its homologs at the mucosal interface. Congeners of BPI are under biopharmaceutical development as novel anti-infective agents, highlighting the potential therapeutic relevance of this protein family.
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A oliveira é uma planta de clima temperado, cuja frutificação necessita de baixas temperaturas no período que antecede a floração. A produção de mudas de boa qualidade dessa cultura é fundamental na implantação do pomar e uma associação com fungos micorrízicos arbusculares (FMAs) pode ser muito importante nesse sentido. No Brasil, não há estudos relacionados à utilização de FMAs na produção de mudas de oliveira. O objetivo deste estudo foi avaliar o efeito da utilização de diferentes espécies de FMAs no desenvolvimento de mudas de cultivares de oliveira com potencial de cultivo na região sul de Minas Gerais. O experimento foi realizado em casa de vegetação avaliando-se três cultivares de oliveira (Arbequina, Grappolo 541- MGS GRAP541 e Maria da Fé - MGS MARIENSE) e quatro tratamentos de inoculação com FMAs (sem inóculo e com inóculo das espécies de FMAs Glomus clarum, Gigaspora rosea ou Acaulospora scrobiculata), de acordo com o fatorial (3 × 4). O delineamento experimental foi inteiramente casualizado, com três repetições. Os FMAs estudados proporcionaram maior massa de matéria seca da parte aérea e raiz das mudas, quando comparadas àquelas não inoculadas, principalmente para a Grappolo 541 (MGS GRAP 541) e Arbequina. A cultivar Maria da Fé (MGS MARIENSE) apresentou baixa dependência micorrízica e menor produção de matéria seca da parte aérea, comparada às outras cultivares.
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Decorrente dos sistemas de manejo empregados no solo, como o sistema de preparo convencional (SPC) versus o sistema de plantio direto de hortaliças (SPDH), modificações nos atributos edáficos ocorrem; por exemplo, nos índices de agregação do solo e seu teor de carbono orgânico total (COT). Objetivaram-se quantificar os teores de COT e avaliar os índices de agregação do solo e a distribuição dos agregados por classes de diâmetro sob cultivo de cebola em SPDH e SPC, comparados a uma área de mata adjacente em Ituporanga, SC. Os tratamentos constituíram-se da semeadura de plantas de cobertura, solteiras e consorciadas, em SPDH: vegetação espontânea (VE); 100 % aveia; 100 % centeio; 100 % nabo-forrageiro; consórcio de nabo-forrageiro (14 %) e centeio (86 %); e consórcio de nabo-forrageiro (14 %) e aveia (86 %). Adicionalmente, foram avaliadas uma área de cultivo de cebola em SPC por ±37 anos e uma área de mata (floresta secundária; ±30 anos), ambas adjacentes ao experimento. Em setembro de 2013, cinco anos após a implantação dos tratamentos com plantas de cobertura, foram coletadas amostras indeformadas do solo nas camadas de 0-5, 5-10 e 10-20 cm e separados os agregados para avaliar a estabilidade via úmida. Nos agregados, foi quantificado o COT; após a separação em classes de diâmetro (8,00 mm>Ø≥0,105 mm), calcularam-se o diâmetro médio ponderado (DMP) e o geométrico (DMG) dos agregados; a distribuição deles em macroagregados (Ø≥2,0 mm), mesoagregados (2,0>Ø≥0,25 mm) e microagregados (Ø<0,25 mm); e o seu índice de sensibilidade (IS). Os dados foram submetidos à análise de variância e de componentes principais (ACP). Os maiores teores de COT foram encontrados na área de mata (52,83; 37,77; e 26,70 g kg-1, respectivamente para 0-5, 5-10 e 10-20 cm); e os menores, no SPC (18,23 g kg-1, 0-5 cm). Os tratamentos com plantas de cobertura, solteiras ou consorciadas, não apresentaram diferenças entre si (p≤0,05) para o COT, nem em relação à área testemunha (VE). O SPC apresentou os menores índices de DMP (3,425; 3,573; e 3,401 mm), DMG (2,438; 2,682; e 2,541 mm) e IS (0,77; 0,79; e 0,81), nas três camadas avaliadas. Para o DMP e DMG, não foram verificadas diferenças (p≤0,05) entre tratamentos no SPDH; porém, esses índices foram superiores aos do SPC; os de DMP, iguais aos da área de mata; e os de DMG, maiores na camada de 0-5 e 5-10 cm. Na camada de 10-20 cm, no SPDH, o tratamento com nabo-forrageiro apresentou maiores valores de DMP (4,520 mm), DMG (4,284 mm) e IS (1,07). Em relação à distribuição dos agregados por classes de diâmetro, o SPC evidenciou, respectivamente, os menores (14,22; 14,75; e 13,86 g) e maiores (4,94; 3,44; e 3,52 g/3,0; 3,0; e 3,76 g) valores para macro e meso/microagregados, enquanto o SPDH demonstrou maiores valores de macroagregados (médias de 19,90; 20,48; e 18,56 g) em comparação à mata (16,0; 16,31; e 15,47 g) e ao SPC (14,22; 14,75; e 13,86 g) nas três camadas avaliadas. O uso de plantas de cobertura, solteiras ou consorciadas, em SPD de cebola foi eficiente para recuperar e aumentar os teores de COT e os índices de DMP, DMG e IS em relação ao SPC; e, em comparação à área de mata, aumentou o DMG (0-5 e 5-10 cm). O nabo-forrageiro aumentou a agregação do solo (DMG e IS) na camada de 10-20 cm em relação aos demais tratamentos com plantas de cobertura. A ACP evidenciou a perda de COT e o aumento dos meso e microagregados no SPC, assim como a substituição do SPC por SPDH com plantas de cobertura elevou a formação de macroagregados estáveis em água, com posterior aumento do DMP, DMG e IS.
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OBJECTIVE: Cultures have limited sensitivity in the diagnosis of prosthetic joint infection (PJI), especially in low-grade infections. We assessed the value of multiplex PCR in differentiating PJI from aseptic failure (AF). METHODS: Included were patients in whom the joint prosthesis was removed and submitted for sonication. The resulting sonication fluid was cultured and investigated by multiplex PCR, and compared with periprosthetic tissue culture. RESULTS: Among 86 explanted prostheses (56 knee, 25 hip, 3 elbow and 2 shoulder prostheses), AF was diagnosed in 62 cases (72%) and PJI in 24 cases (28%). PJI was more common detected by multiplex PCR (n=23, 96%) than by periprosthetic tissue (n=17, 71%, p=0.031) or sonication fluid culture (n=16, 67%, p=0.016). Among 12 patients with PJI who previously received antibiotics, periprosthetic tissue cultures were positive in 8 cases (67%), sonication fluid cultures in 6 cases (50%) and multiplex PCR in 11 cases (92%). In AF cases, periprosthetic tissue grew organisms in 11% and sonication fluid in 10%, whereas multiplex PCR detected no organisms. CONCLUSIONS: Multiplex PCR of sonication fluid demonstrated high sensitivity (96%) and specificity (100%) for diagnosing PJI, providing good discriminative power towards AF, especially in patients previously receiving antibiotics.