9 resultados para 60-455
em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo
Resumo:
The spatial and temporal variation of microphytobenthic biomass in the nearshore zone of Martel Inlet (King George Island, Antarctica) was estimated at several sites and depths (10-60 m), during three summer periods (1996/1997, 1997/1998, 2004/2005). The mean values were inversely related to the bathymetric gradient: higher ones at 10-20 m depth (136.2 +/- A 112.5 mg Chl a m(-2), 261.7 +/- A 455.9 mg Phaeo m(-2)), intermediate at 20-30 m (55.6 +/- A 39.5 mg Chl a m(-2), 108.8 +/- A 73.0 mg Phaeo m(-2)) and lower ones at 40-60 m (22.7 +/- A 23.7 mg Chl a m(-2), 58.3 +/- A 38.9 mg Phaeo m(-2)). There was also a reduction in the Chl a/Phaeo ratio with depth, from 3.2 +/- A 3.2 (10-20 m) to 0.7 +/- A 1.0 (40-60 m), showing a higher contribution of senescent phytoplankton and/or macroalgae debris at the deeper sites and the limited light flux reaching the bottom. Horizontal differences found in the biomass throughout the inlet could not be clearly related to hydrodynamics or proximity to glaciers, but with sediment characteristics. An inter-summer variation was observed: the first summer presented the highest microphytobenthic biomass apparently related to more hydrodynamic conditions, which causes the deposition of allochthonous material.
Resumo:
Novel water-soluble decacationically armed C-60 and C-70 decaiodide monoadducts, C-60- and C-70[>M(C3N6+C3)(2)], were synthesized, characterized, and applied as photosensitizers and potential nano-PDT agents against pathogenic bacteria and cancer cells. A high number of cationic charges per fullerene cage and H-bonding moieties were designed for rapid binding to the anionic residues displayed on the outer parts of bacterial cell walls. In the presence of a high number of electron-donating iodide anions as parts of quaternary ammonium salts in the arm region, we found that C-70[>M(C3N6+C3)(2)] produced more HO center dot than C-60[>M(C3N6+C3)(2)], in addition to O-1(2). This finding offers an explanation of the preferential killing of Gram-positive and Gram-negative bacteria by C-60[>M(C3N6+C3)(2)] and C-70[>M(C3N6+C3)(2)], respectively. The hypothesis is that O-1(2) can diffuse more easily into porous cell walls of Gram-positive bacteria to reach sensitive sites, while the less permeable Gram-negative bacterial cell wall needs the more reactive HO center dot to cause real damage.
Resumo:
The aim of this study was to investigate the effects of beta-alanine supplementation on exercise capacity and the muscle carnosine content in elderly subjects. Eighteen healthy elderly subjects (60-80 years, 10 female and 4 male) were randomly assigned to receive either beta-alanine (BA, n = 12) or placebo (PL, n = 6) for 12 weeks. The BA group received 3.2 g of beta-alanine per day (2 x 800 mg sustained-release Carnosyn (TM) tablets, given 2 times per day). The PL group received 2 x (2 x 800 mg) of a matched placebo. At baseline (PRE) and after 12 weeks (POST-12) of supplementation, assessments were made of the muscle carnosine content, anaerobic exercise capacity, muscle function, quality of life, physical activity and food intake. A significant increase in the muscle carnosine content of the gastrocnemius muscle was shown in the BA group (+85.4%) when compared with the PL group (+7.2%) (p = 0.004; ES: 1.21). The time-to-exhaustion in the constant-load submaximal test (i.e., TLIM) was significantly improved (p = 0.05; ES: 1.71) in the BA group (+36.5%) versus the PL group (+8.6%). Similarly, time-to-exhaustion in the incremental test was also significantly increased (p = 0.04; ES 1.03) following beta-alanine supplementation (+12.2%) when compared with placebo (+0.1%). Significant positive correlations were also shown between the relative change in the muscle carnosine content and the relative change in the time-to-exhaustion in the TLIM test (r = 0.62; p = 0.01) and in the incremental test (r = 0.48; p = 0.02). In summary, the current data indicate for the first time, that beta-alanine supplementation is effective in increasing the muscle carnosine content in healthy elderly subjects, with subsequent improvement in their exercise capacity.
Resumo:
Background: Candidemia affects patient populations from neonates to the elderly. Despite this, little information is available about the epidemiology of candidemia in elderly patients. Methods: We performed a retrospective analysis of 987 episodes of candidemia in adults (>14 years of age) from the databases of three laboratory-based surveys of candidemia performed at 14 tertiary care hospitals. Patients aged >= 60 years were considered elderly (group 1, n = 455, 46%) and were compared to younger patients (group 2, n = 532, 54%) regarding demographics, underlying diseases, comorbidities, exposure to medical procedures, species, treatment, and outcome. Results: The median APACHE II score was significantly higher in the elderly patients (19 vs. 15, p = 0.03). Variables that were observed significantly more frequently in elderly patients included admission to an intensive care unit, diabetes mellitus, renal failure, cardiac disease, lung disease, receipt of antibiotics or H2 blockers, insertion of a central venous catheter, mechanical ventilation, and candidemia due to Candida tropicalis. The 30-day mortality of elderly patients was significantly higher than that of younger patients (70% vs. 45%, p < 0.001). Factors associated with higher mortality by multivariate analysis included APACHE II score and being in group 1 (elderly). Factors associated with mortality in elderly patients were lung disease and the receipt of mechanical ventilation. Conclusions: Elderly patients account for a substantial proportion of patients with candidemia and have a higher mortality compared to younger patients. (C) 2012 International Society for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.
Resumo:
In this work the proton irradiation influence on Multiple Gate MOSFETs (MuGFETs) performance is investigated. This analysis was performed through basic and analog parameters considering four different splits (unstrained, uniaxial, biaxial, uniaxial+biaxial). Although the influence of radiation is more pronounced for p-channel devices, in pMuGFETs devices, the radiation promotes a higher immunity to the back interface conduction resulting in the analog performance improvement. On the other hand, the proton irradiation results in a degradation of the post-irradiated n-channel transistors behavior. The unit gain frequency showed to be strongly dependent on stress efficiency and the radiation results in an increase of the unit gain frequency for splits with high stress effectiveness for both cases p- and nMuGFETs.
Resumo:
Clin Microbiol Infect 2012; 18: E380E388 Abstract In this randomized clinical trial, the clinical and mycological efficacy of Photodynamic Therapy (PDT) was compared with that of topical antifungal therapy for the treatment of denture stomatitis (DS) and the prevalence of Candida species was identified. Patients were randomly assigned to one of two groups (n = 20 each); in the nystatin (NYT) group patients received topical treatment with nystatin (100 000 IU) four times daily for 15 days and in the PDT group the denture and palate of patients were sprayed with 500 mg/L of Photogem (R), and after 30 min of incubation, were illuminated by light emitting-diode light at 455 nm (37.5 and 122 J/cm2, respectively) three times a week for 15 days. Mycological cultures taken from dentures and palates and standard photographs of the palates were taken at baseline (day 0), at the end of the treatment (day 15) and at the follow-up time intervals (days 30, 60 and 90). Colonies were quantified (CFU/mL) and identified by biochemical tests. Data were analysed by Fishers exact test, analysis of variance and Tukey tests and ? test (a = 0.05). Both treatments significantly reduced the CFU/mL at the end of the treatments and on day 30 of the follow-up period (p <0.05). The NYT and PDT groups showed clinical success rates of 53% and 45%, respectively. Candida albicans was the most prevalent species identified. PDT was as effective as topical nystatin in the treatment of DS.
Resumo:
OBJETIVO: Investigar a prevalência da desnutrição e fatores associados em crianças menores de 60 meses em dois municípios do Estado do Acre. MÉTODOS: Estudo transversal de base populacional realizado com 667 crianças da área urbana dos municípios de Acrelândia e Assis Brasil. A prevalência da desnutrição foi calculada pelo padrão de crescimento da Organização Mundial da Saúde de 2006, com o ponto de corte -2 escores Z. Informações sobre condições socioeconômicas, acesso aos serviços e cuidado da criança, peso ao nascer e morbidade foram obtidas por questionário estruturado. A regressão de Poisson foi utilizada para identificar os fatores associados à desnutrição de crianças. RESULTADOS: A prevalência do déficit estatura para idade e déficit peso para estatura foi de 9,9% e 4,1%, respectivamente. Os fatores associados ao déficit estatura para idade foram o baixo índice de riqueza (razão de prevalência [RP]: 1,74; intervalo de confiança em 95% [IC95%]: 0,95 - 3,18), analfabetismo do pai ou padrasto (RP: 1,82; IC95%: 1,01 - 3,27), ter 2 ou mais irmãos menores (RP: 2,88; IC95%: 1,45 - 5,72), ausência da mãe biológica no domicílio (RP: 2,63; IC95%: 1,32 - 5,24) e exposição ao esgoto a céu aberto no âmbito domiciliar (RP: 2,46; IC95%: 1,51 - 4,00). Somente o baixo peso ao nascer mostrou-se como fator associado ao déficit peso para estatura (RP: 2,91; IC95%: 1,16 - 7,24). CONCLUSÕES: Nos municípios estudados, a desnutrição em crianças menores de 60 meses apresenta-se como um importante problema de saúde pública, associado aos indicadores de iniquidades sociais, acesso aos serviços de saúde e ausência da mãe no domicílio.
Resumo:
BACKGROUND: Porphyria cutanea tarda is the most common form of porphyria, characterized by the decreased activity of the uroporphyrinogen decarboxylase enzyme. Several reports associated HFE gene mutations of hereditary hemochromatosis with porphyria cutanea tarda worldwide, although up to date only one study has been conducted in Brazil. OBJECTIVES: Investigation of porphyria cutanea tarda association with C282Y and H63D mutations in the HFE gene. Identification of precipitating factors (hepatitis C, HIV, alcoholism and estrogen) and their link with HFE mutations. METHODS: An ambispective study of 60 patients with PCT was conducted during the period from 2003 to 2012. Serological tests for hepatitis C and HIV were performed and histories of alcohol abuse and estrogen intake were investigated. HFE mutations were identified with real-time PCR. RESULTS: Porphyria cutanea tarda predominated in males and alcohol abuse was the main precipitating factor. Estrogen intake was the sole precipitating factor present in 25% of female patients. Hepatitis C was present in 41.7%. All HIV-positive patients (15.3%) had a history of alcohol abuse. Allele frequency for HFE mutations, i.e., C282Y (p = 0.0001) and H63D (p = 0.0004), were significantly higher in porphyria cutanea tarda patients, compared to control group. HFE mutations had no association with the other precipitating factors. CONCLUSIONS: Alcohol abuse, hepatitis C and estrogen intake are prevalent precipitating factors in our porphyria cutanea tarda population; however, hemochromatosis in itself can also contribute to the outbreak of porphyria cutanea tarda, which makes the research for HFE mutations necessary in these patients