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Purpose: The bladder is normally impermeable to possible hostile environmental factors and toxic urinary wastes. Any disruption of the permeability barrier would permit the leakage of urine constituents into the underlying cells layers and subsequent inflammation. Protamine sulfate, which increases urothelial permeability, is used in experimental models of cystitis. We examined whether protamine sulfate alone could cause bladder inflammation or if the association of protamine sulfate and urine is needed for this condition. Materials and Methods: Female Wistar rats (Center for the Development of Experimental Models for Medicine and Biology, Federal University of Sao Paulo, Sao Paulo, Brazil) had the bladder catheterized and instilled with protamine sulfate (10 mg) or sterile saline for 30 minutes. To exclude urine other groups of rats underwent bilateral nephrectomy and the same procedure was used. One day after instillation the bladders were removed for histopathology. Edema and vascular congestion were graded from 0-none to 3-severe. Polymorphonuclear and mast cells were counted. The Kruskal-Wallis test was performed for statistical analysis. Results: Intravesical instillation of protamine sulfate in nonnephrectomized rats led to inflammation, in contrast to findings in rats instilled with saline. On the other hand, nephrectomized rats showed no inflammatory changes following the instillation of protamine sulfate or saline. The mast cell count was similar in all groups. Conclusions: Bladder inflammation in this experimental model of urothelial injury was not due to protamine sulfate alone. The association of protamine sulfate and urine was necessary to trigger the inflammatory cascade. Thus, urine indeed has an important role in the development of bladder inflammation in an environment of higher urothelial permeability.

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Liver transplantation was first performed at the University of Sao Paulo School of Medicine in 1968. Since then, the patient waiting list for liver transplantation has increased at a rate of 150 new cases per month. Liver transplantation itself rose 1.84-fold (from 160 to 295) from 1988 to 2004. However, the number of patients on the liver waiting list jumped 2.71-fold (from 553 to 1500). Consequently, the number of deaths on the liver waiting list moved to a higher level, from 321 to 671, increasing 2.09-fold. We have applied a mathematical model to analyze the potential impact of using a donation after cardiac death (DCD) policy on our liver transplantation program and on the waiting list. Five thousand one hundred people died because of accidents and other violent causes in our state in 2004; of these, only 295 were donors of liver grafts that were transplanted. The model assumed that 5% of these grafts would have been DCD. We found a relative reduction of 27% in the size of the liver transplantation waiting list if DCD had been used by assuming that 248 additional liver transplants would have been performed annually. In conclusion, the use of DCD in our transplantation program would reduce the pressure on our liver transplantation waiting list, reducing it by at least 27%. On the basis of this model, the projected number of averted deaths is about 41,487 in the next 20 years. Liver Transpl 14:1732-1736, 2008. (C) 2008 AASLD.

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O tamanho e a complexidade do desafio de combater a pobreza t??m criado a necessidade de se identificar novas maneiras de atacar o problema. Um importante elemento da atual discuss??o ?? o envolvimento dos stakeholders prim??rios nas atividades da interven????o de desenvolvimento. O presente trabalho revisa e sintetiza a literatura especializada para analisar as contribui????es da participa????o para a redu????o da pobreza. Ele identificou que participa????o aumenta o impacto das estrat??gias de redu????o da pobreza, por meio do empoderamento dos stakeholders prim??rios e de melhorias na efetividade, na efici??ncia e na sustentabilidade das interven????es. Os estudos de caso indicam, tamb??m, que altos n??veis de participa????o tendem a contribuir mais para o sucesso da estrat??gia. Contudo, garantir uma ???real??? participa????o dos benefici??rios n??o ?? f??cil. Como resultado desse estudo, s??o dadas algumas recomenda????es para futuras pol??ticas de combate ?? pobreza. Se adotadas, elas podem ajudar a vencer as dificuldades e desafios apontados e a maximizar as contribui????es da participa????o.

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A economia informal compõe o mundo do trabalho de todas as sociedades capitalistas, em menor ou em maior grau. No Brasil, historicamente observa-se que esse fenômeno tem sido sempre muito abrangente, sobretudo motivado pelo e resultante do contexto socioeconômico, jurídico e político. Devido às idiossincrasias nacionais, desde o surgimento do mercado de trabalho no país, esta situação persiste em diversos panoramas e com vários matizes, obstaculizando uma melhor performance global da economia brasileira e negando oportunidades de desenvolvimento individual e social ao longo do tempo. Sendo assim, e através do prisma da Economia Social e do Trabalho, o objetivo desta dissertação é analisar os principais fatores conjunturais e estruturais da informalidade observada no mercado nacional de trabalho no interregno 1980-2012, apresentando a dimensão desse problema e expondo suas raízes econômicas e institucionais, a fim de contribuir com novos elementos para o debate da informalidade em nível nacional. A hipótese central dessa pesquisa é de que o elevado GI no Brasil persiste essencialmente – mesmo que com diferentes especificidades históricas – ao nível das mentalidades dos diversos agentes, isto é, antes de ter-se um mercado nacional de trabalho com um alto GI, tem-se uma sociedade brasileira altamente informal. A instituição “trabalho informal” persiste como um hábito incrustado mesmo diante de mudanças de ordem socioeconômica, o que impede que grande parcela da população brasileira tenha acesso ao trabalho formalizado e decente (a là OIT). É mister que haja maior efetividade das leis e aprimoramentos institucionais acompanhados de coordenação e “vontade política”, alicerçados pela tomada de consciência crescente da sociedade civil no que se refere à importância da formalização e aos males da informalidade tanto para seus cidadãos quanto para a nação. Sugere-se como uma possível alternativa para diminuir o GI de forma mais consistente a consideração, para além dos aspectos econômicos e jurídicos, do arcabouço cultural, histórico, comportamental e dos hábitos sociais incrustados que os condicionam e os orientam. Isto porque são estes os eixos que norteiam o processo de desenvolvimento individual e social. Nesse sentido, o estudo (de caráter descritivo e analítico) é fundamentado pelas teorias sistêmicas e multidisciplinares desenvolvidas por Karl Paul Polanyi e Amartya Kumar Sen, interpretadas como artífices de uma vida digna, além de apregoarem o “reincrustamento” da economia na sociedade e, por analogia, o “desincrustamento” da informalidade institucionalmente enraizada na sociedade brasileira. Isso se dará à medida que forem expandidas as liberdades instrumentais e substantivas, em uma espécie de “causação circular cumulativa” aplicada à questão da informalidade, tendo como “efeito colateral altamente desejável” o desenvolvimento socioeconômico. As principais contribuições deste estudo emergiram justamente das concepções teóricas dos dois autores, combinadas aos nexos de convergência estabelecidos entre a economia brasileira, seus desdobramentos institucionais e a informalidade no mercado nacional de trabalho no período estudado.

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The main aims of this work are the development and the validation of one generic algorithm to provide the optimal control of small power wind generators. That means up to 40 kW and blades with fixed pitch angle. This algorithm allows the development of controllers to fetch the wind generators at the desired operational point in variable operating conditions. The problems posed by the variable wind intensity are solved using the proposed algorithm. This is done with no explicit measure of the wind velocity, and so no special equipment or anemometer is required to compute or measure the wind velocity.

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An accurate and sensitive method for determination of 18 polycyclic aromatic hydrocarbons (PAHs) (16 PAHs considered by USEPA as priority pollutants, dibenzo[a,l]pyrene and benzo[j]fluoranthene) in fish samples was validated. Analysis was performed by microwave-assisted extraction and liquid chromatography with photodiode array and fluorescence detection. Response surface methodology was used to find the optimal extraction parameters. Validation of the overall methodology was performed by spiking assays at four levels and using SRM 2977. Quantification limits ranging from 0.15–27.16 ng/g wet weight were obtained. The established method was applied in edible tissues of three commonly consumed and commercially valuable fish species (sardine, chub mackerel and horse mackerel) originated from Atlantic Ocean. Variable levels of naphthalene (1.03–2.95 ng/g wet weight), fluorene (0.34–1.09 ng/g wet weight) and phenanthrene (0.34–3.54 ng/g wet weight) were detected in the analysed samples. None of the samples contained detectable amounts of benzo[a]pyrene, the marker used for evaluating the occurrence and carcinogenic effects of PAHs in food.

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Nesta dissertação apresenta-se um motor em disco polifásico inovador bem como uma estratégia de controlo com base no método de variação de velocidade por comutação do número de pares de pólos. A configuração das bobinas aliada à escolha das correntes e tensões que se injectam nas bobinas dos estatores, permite comutar electronicamente o número de pólos do motor entre 2, 4 6 e 8 pólos, conseguindo-se controlar a característica binário/velocidade do motor. O motor em disco possui a bobinagem feita em cobre com dois semi-estatores, em que quando utiliza o rotor em alumínio (com condutividade diferente de zero) comporta-se como um motor de indução convencional. Quando se substitui o rotor em alumínio por um constituído por um supercondutor de alta temperatura (SAT), o dispositivo comporta-se como um motor de histerese. O princípio de funcionamento do motor em disco convencional é baseado na indução de força electromotrizes no rotor e, consequentemente, uma vez que o alumínio é bom condutor eléctrico, correntes eléctricas induzidas, originadas por haver um campo magnético variável que é criado pelos semi-estatores. O comportamento deste tipo de motores, no que diz respeito a principais características (como o binário/velocidade para os diferentes números de pares de pólos), circuito equivalente de Steinmetz, entre outras teorias associadas é já conhecido há bastante tempo. O princípio de funcionamento do motor SAT é diferente do apresentado anteriormente, funciona com base na dinâmica de vórtices e devido ao facto de aparecer o fenómeno de ancoragem de fluxo (flux pinning) nos supercondutores de alta temperatura. Como o campo magnético varia, então o disco roda. Este motor tem um princípio de funcionamento muito mais complexo que o motor de indução sendo a obtenção do modelo do motor SAT complicada. A obtenção do modelo do motor SAT não é abordado nesta dissertação. Os comportamentos e modos de operação do motor com disco de alumínio e em materiais SAT são simulados através de um programa comercial de elementos finitos, nesta dissertação, sendo a supercondutividade simulada com base na relação entre o campo eléctrico e a densidade de corrente pela lei da potenciação (E-J power law). Com as simulações pretende-se comparar o rendimento electromecânico de ambos os motores.

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OBJECTIVES: To investigate the development of the ureterovesical junction in rats. METHODS: A total of 110 albino rats (50 prenatal and 60 newborn) with a gestation of 21 days were studied at the age of 17 days after conception until 5 days after birth. The lower urinary tract was microdissected. Microphotography (110 animals), histologic examination (44 animals), and scanning electron microscopy (66 animals) of the ureterovesical junction were performed. Urea and creatinine from the amniotic fluid of 20 fetuses and from the urine of 10 neonates were measured. RESULTS: At day 17 after conception, separate penetration of the mesonephric duct and ureter into the wall of the urogenital sinus was observed. Continuity between the lumen of the ureter and the urogenital sinus was established on day 19 after conception. The straight passage of the intramural ureter into the urogenital sinus at day 17 after conception changed to the definitive L-shape with a vertical entry into the bladder on day 5 after birth. In the distal ureter, the change of the mesenchymal tissue into immature smooth muscle was first observed at birth, and the muscle became mature on the fifth postnatal day. At birth, Waldeyer's sheath was recognized. The creatinine and urea levels were stable prenatally (average 22.4 micromol/L and 6.88 mmol/L, respectively) and rose significantly postnatally (average 133 micromol/L and 32.65 mmol/L, respectively). CONCLUSIONS: The attachment of the ureter to the urogenital sinus and later to the bladder, the modification of its passage, and its mobility within Waldeyer's sheath may be essential in preventing vesicoureteral reflux. The production of urine and its flow does not seem to be the trigger of ureteral smooth muscle formation.

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Vaniprevir (MK-7009) is a macrocyclic hepatitis C virus (HCV) nonstructural protein 3/4A protease inhibitor. The aim of the present phase II study was to examine virologic response rates with vaniprevir in combination with pegylated interferon alpha-2a (Peg-IFN-α-2a) plus ribavirin (RBV). In this double-blind, placebo-controlled, dose-ranging study, treatment-naïve patients with HCV genotype 1 infection (n = 94) were randomized to receive open-label Peg-IFN-α-2a (180 μg/week) and RBV (1,000-1,200 mg/day) in combination with blinded placebo or vaniprevir (300 mg twice-daily [BID], 600 mg BID, 600 mg once-daily [QD], or 800 mg QD) for 28 days, then open-label Peg-IFN-α-2a and RBV for an additional 44 weeks. The primary efficacy endpoint was rapid viral response (RVR), defined as undetectable plasma HCV RNA at week 4. Across all doses, vaniprevir was associated with a rapid two-phase decline in viral load, with HCV RNA levels approximately 3 log(10) IU/mL lower in vaniprevir-treated patients, compared to placebo recipients. Rates of RVR were significantly higher in each of the vaniprevir dose groups, compared to the control regimen (68.8%-83.3% versus 5.6%; P < 0.001 for all comparisons). There were numerically higher, but not statistically significant, early and sustained virologic response rates with vaniprevir, as compared to placebo. Resistance profile was predictable, with variants at R155 and D168 detected in a small number of patients. No relationship between interleukin-28B genotype and treatment outcomes was demonstrated in this study. The incidence of adverse events was generally comparable between vaniprevir and placebo recipients; however, vomiting appeared to be more common at higher vaniprevir doses. CONCLUSION: Vaniprevir is a potent HCV protease inhibitor with a predictable resistance profile and favorable safety profile that is suitable for QD or BID administration.

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PURPOSE: Several studies observed a female advantage in the prognosis of cutaneous melanoma, for which behavioral factors or an underlying biologic mechanism might be responsible. Using complete and reliable follow-up data from four phase III trials of the European Organisation for Research and Treatment of Cancer (EORTC) Melanoma Group, we explored the female advantage across multiple end points and in relation to other important prognostic indicators. PATIENTS AND METHODS: Patients diagnosed with localized melanoma were included in EORTC adjuvant treatment trials 18832, 18871, 18952, and 18961 and randomly assigned during the period of 1984 to 2005. Cox proportional hazard models were used to calculate hazard ratios (HRs) and 95% CIs for women compared with men, adjusted for age, Breslow thickness, body site, ulceration, performed lymph node dissection, and treatment. RESULTS: A total of 2,672 patients with stage I/II melanoma were included. Women had a highly consistent and independent advantage in overall survival (adjusted HR, 0.70; 95% CI, 0.59 to 0.83), disease-specific survival (adjusted HR, 0.74; 95% CI, 0.62 to 0.88), time to lymph node metastasis (adjusted HR, 0.70; 95% CI, 0.51 to 0.96), and time to distant metastasis (adjusted HR, 0.69; 95% CI, 0.59 to 0.81). Subgroup analysis showed that the female advantage was consistent across all prognostic subgroups (with the possible exception of head and neck melanomas) and in pre- and postmenopausal age groups. CONCLUSION: Women have a consistent and independent relative advantage in all aspects of the progression of localized melanoma of approximately 30%, most likely caused by an underlying biologic sex difference.

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Purpose: Surgery remains the treatment of choice for localized renal neoplasms. While radical nephrectomy was long considered the gold standard, partial nephrectomy has equivalent oncological results for small tumors. The role of negative surgical margins continues to be debated. Intraoperative frozen section analysis is expensive and time-consuming. We assessed the feasibility of intraoperative ex vivo ultrasound of resection margins in patients undergoing partial nephrectomy and its correlation with margin status on definitive pathological evaluation.Materials and Methods: A study was done at 2 institutions from February 2008 to March 2011. Patients undergoing partial nephrectomy for T1-T2 renal tumors were included in analysis. Partial nephrectomy was done by a standardized minimal healthy tissue margin technique. After resection the specimen was kept in saline and tumor margin status was immediately determined by ex vivo ultrasound. Sequential images were obtained to evaluate the whole tumor pseudocapsule. Results were compared with margin status on definitive pathological evaluation.Results: A total of 19 men and 14 women with a mean +/- SD age of 62 +/- 11 years were included in analysis. Intraoperative ex vivo ultrasound revealed negative surgical margins in 30 cases and positive margins in 2 while it could not be done in 1. Final pathological results revealed negative margins in all except 1 case. Ultrasound sensitivity and specificity were 100% and 97%, respectively. Median ultrasound duration was 1 minute. Mean tumor and margin size was 3.6 +/- 2.2 cm and 1.5 +/- 0.7 mm, respectively.Conclusions: Intraoperative ex vivo ultrasound of resection margins in patients undergoing partial nephrectomy is feasible and efficient. Large sample studies are needed to confirm its promising accuracy to determine margin status.

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A 56-year-old man presented with a "nail" growing at the base of his glans penis. The tumor was locally excised, and microscopic examination revealed papillomatosis and hyperkeratosis of the malpighian epithelium, with a strong inflammatory reaction of the chorion and signs of local microinvasion, as well as the presence of well-differentiated squamous epithelial cells. The surgical margins were negative. The differential diagnosis was made between a benign papillomatous proliferation and verrucous carcinoma.