132 resultados para Effective focal length


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Prompt and specific identification of fungemia agents is important in order to define clinical treatment. However, in most cases conventional culture identification can be considered to be time-consuming and not without errors. The aim of the present study was to identify the following fungemia agents: Candida albicans, Candida parapsilosis, Candida tropicalis, Candida glabrata, Cryptococcus neoformans, Cryptococcus gattii, and Histoplasma capsulatum using the polymerase chain reaction and restriction fragment length polymorphism analysis (PCR/RFLP). More specifically: a) to evaluate 3 different amplification regions, b) to investigate 3 different restriction enzymes, and c) to use the best PCR/RFLP procedure to indentify 60 fungemia agents from a culture collection. All 3 pairs of primers (ITS1/ITS4, NL4/ITS5 and Primer1/Primer2) were able to amplify DNA from the reference strains. However, the size of these PCR products did not permit the identification of all the species studied. Three restriction enzymes were used to digest the PCR products: HaeIII, Ddel and Bfal. Among the combinations of pairs of primers and restriction enzymes, only one (primer pair NL4/ITS5 and restriction enzyme Ddel) produced a specific RFLP pattern for each microorganism studied. Sixty cultures of fungemia agents (selected from the culture collection of Fundação de Medicina Tropical do Amazonas - FMTAM) were correctly identified by PCR/RFLP using the prime pair NL4/ITS5 and Ddel. We conclude that the method proved to be both simple and reproducible, and may offer potential advantages over phenotyping methods.

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A recent assessment of 4400 postgraduate courses in Brazil by CAPES (a federal government agency dedicated to the improvement of the quality of and research at the postgraduate level) stimulated a large amount of manifestations in the press, scientific journals and scientific congresses. This gigantic effort to classify 16,400 scientific journals in order to provide indicators for assessment proved to be puzzling and methodologically erroneous in terms of gauging the institutions from a metric point of view. A simple algorithm is proposed here to weigh the scientometric indicators that should be considered in the assessment of a scientific institution. I conclude here that the simple gauge of the total number of citations accounts for both the productivity of scientists and the impact of articles. The effort spent in this exercise is relatively small, and the sources of information are fully accessible. As an exercise to estimate the value of the methodology, 12 institutions of physics (10 from Brazil, one from the USA and one from Italy) have been evaluated.

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The objective of this study is to retrospectively report the results of interventions for controlling a vancomycin-resistant enterococcus (VRE) outbreak in a tertiary-care pediatric intensive care unit (PICU) of a University Hospital. After identification of the outbreak, interventions were made at the following levels: patient care, microbiological surveillance, and medical and nursing staff training. Data were collected from computer-based databases and from the electronic prescription system. Vancomycin use progressively increased after March 2008, peaking in August 2009. Five cases of VRE infection were identified, with 3 deaths. After the interventions, we noted a significant reduction in vancomycin prescription and use (75% reduction), and the last case of VRE infection was identified 4 months later. The survivors remained colonized until hospital discharge. After interventions there was a transient increase in PICU length-of-stay and mortality. Since then, the use of vancomycin has remained relatively constant and strict, no other cases of VRE infection or colonization have been identified and length-of-stay and mortality returned to baseline. In conclusion, we showed that a bundle intervention aiming at a strict control of vancomycin use and full compliance with the Hospital Infection Control Practices Advisory Committee guidelines, along with contact precautions and hand-hygiene promotion, can be effective in reducing vancomycin use and the emergence and spread of vancomycin-resistant bacteria in a tertiary-care PICU.

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Effective statin therapy is associated with a marked reduction of cardiovascular events. However, the explanation for full benefits obtained for LDL cholesterol targets by combined lipid-lowering therapy is controversial. Our study compared the effects of two equally effective lipid-lowering strategies on markers of cholesterol synthesis and absorption. A prospective, open label, randomized, parallel design study, with blinded endpoints, included 116 subjects. We compared the effects of a 12-week treatment with 40 mg rosuvastatin or the combination of 40 mg simvastatin/10 mg ezetimibe on markers of cholesterol absorption (campesterol and β-sitosterol), synthesis (desmosterol), and their ratios to cholesterol. Both therapies similarly decreased total and LDL cholesterol, triglycerides and apolipoprotein B, and increased apolipoprotein A1 (P < 0.05 vs baseline for all). Simvastatin/ezetimibe increased plasma desmosterol (P = 0.012 vs baseline), and decreased campesterol and β-sitosterol (P < 0.0001 vs baseline for both), with higher desmosterol (P = 0.007) and lower campesterol and β-sitosterol compared to rosuvastatin, (P < 0.0001, for both). In addition, rosuvastatin increased the ratios of these markers to cholesterol (P < 0.002 vs baseline for all), whereas simvastatin/ezetimibe significantly decreased the campesterol/cholesterol ratio (P = 0.008 vs baseline) and tripled the desmosterol/cholesterol ratio (P < 0.0001 vs baseline). The campesterol/cholesterol and β-sitosterol/cholesterol ratios were lower, whereas the desmosterol/cholesterol ratio was higher in patients receiving simvastatin/ezetimibe (P < 0.0001 vs rosuvastatin, for all). Pronounced differences in markers of cholesterol absorption and synthesis were observed between two equally effective lipid-lowering strategies.

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Cardiac contusion is a potentially fatal complication of blunt chest trauma. The effects of a combination of quercetin and methylprednisolone against trauma-induced cardiac contusion were studied. Thirty-five female Sprague-Dawley rats were divided into five groups (n=7) as follows: sham, cardiac contusion with no therapy, treated with methylprednisolone (30 mg/kg on the first day, and 3 mg/kg on the following days), treated with quercetin (50 mg·kg−1·day−1), and treated with a combination of methylprednisolone and quercetin. Serum troponin I (Tn-I) and tumor necrosis factor-alpha (TNF-α) levels and cardiac histopathological findings were evaluated. Tn-I and TNF-α levels were elevated after contusion (P=0.001 and P=0.001). Seven days later, Tn-I and TNF-α levels decreased in the rats treated with methylprednisolone, quercetin, and the combination of methylprednisolone and quercetin compared to the rats without therapy, but a statistical significance was found only with the combination therapy (P=0.001 and P=0.011, respectively). Histopathological degeneration and necrosis scores were statistically lower in the methylprednisolone and quercetin combination group compared to the group treated only with methylprednisolone (P=0.017 and P=0.007, respectively). However, only degeneration scores were lower in the combination therapy group compared to the group treated only with quercetin (P=0.017). Inducible nitric oxide synthase positivity scores were decreased in all treatment groups compared to the untreated groups (P=0.097, P=0.026, and P=0.004, respectively). We conclude that a combination of quercetin and methylprednisolone can be used for the specific treatment of cardiac contusion.

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DNA hypomethylation may activate oncogene transcription, thus promoting carcinogenesis and tumor development. S-adenosylmethionine (SAM) is a methyl donor in numerous methylation reactions and acts as an inhibitor of intracellular demethylase activity, which results in hypermethylation of DNA. The main objectives of this study were to determine whether DNA hypomethylation correlated with vascular endothelial growth factor-C (VEGF-C) expression, and the effect of SAM on VEGF-C methylation and gastric cancer growth inhibition. VEGF-C expression was assayed by Western blotting and RT-qPCR in gastric cancer cells, and by immunohistochemistry in tumor xenografts. VEGF-C methylation was assayed by bisulfite DNA sequencing. The effect of SAM on cell apoptosis was assayed by flow cytometry analyses and its effect on cancer growth was assessed in nude mice. The VEGF-C promoters of MGC-803, BGC-823, and SGC-7901 gastric cancer cells, which normally express VEGF-C, were nearly unmethylated. After SAM treatment, the VEGF-C promoters in these cells were highly methylated and VEGF-C expression was downregulated. SAM also significantly inhibited tumor growthin vitro and in vivo. DNA methylation regulates expression of VEGF-C. SAM can effectively induce VEGF-C methylation, reduce the expression of VEGF-C, and inhibit tumor growth. SAM has potential as a drug therapy to silence oncogenes and block the progression of gastric cancer.

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The effective diffusivity of clove essential oil in subcritical liquid CO2 was estimated. The experimental apparatus employed was a fixed-bed extractor. The fixed bed was formed with grounded (mesh -32 + 65) and compacted clove buds which were considered a solid element. The effective diffusion coefficient was evaluated by fitting the experimental concentration profile to the unsteady state mass balance equation for unidirectional diffusion in a finite solid medium. The diffusion coefficient was related to the concentration of oil in the solid by an exponential function. The estimated values of the effective diffusion coefficient varied from 3.64 to 5.22x10-10 m2/s. The average relative errors were lower than 3.1%.

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Celery (Apium graveolens L. var. secalinum Alef) leaves with 50±0.07 g weight and 91.75±0.15% humidity (~11.21 db) were dried using 8 different microwave power densities ranging between 1.8-20 W g-1, until the humidity fell down to 8.95±0.23% (~0.1 db). Microwave drying processes were completed between 5.5 and 77 min depending on the microwave power densities. In this study, measured values were compared with predicted values obtained from twenty thin layer drying theoretical, semi-empirical and empirical equations with a new thin layer drying equation. Within applied microwave power density; models whose coefficient and correlation (R²) values are highest were chosen as the best models. Weibull distribution model gave the most suitable predictions at all power density. At increasing microwave power densities, the effective moisture diffusivity values ranged from 1.595 10-10 to 6.377 10-12 m2 s-1. The activation energy was calculated using an exponential expression based on Arrhenius equation. The linear relationship between the drying rate constant and effective moisture diffusivity gave the best fit.

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Pseudomonas oleovorans were grown on sugary cassava extracts supplemented with andiroba oil for the synthesis of a mediumchain- length polyhydroxyalkanoate (PHA MCL). The concentration of total sugars in the extract was approximately: 40 g/L in culture 1, 15 g/L in cultures 2 and 3, and 10 g/L in culture 4. Supplementation with 1% andiroba oil and 0.2 g/L of (NH4)2HPO4 was performed 6.5 hours after growth in culture 3, and supplementation with the same amount of andiroba oil and 2.4 g/L of (NH4)2HPO4 was performed at the beginning of growth in culture 4. The synthesis resulted mainly in 3-hydroxy-decanoate and 3-hydroxy-dodecanoate units; 3-hydroxy-butyrate, 3-hydroxy-hexanoate; and 3-hydroxy-octanoate monomers were also produced but in smaller proportions. P. oleovorans significantly accumulated PHA MCL in the deceleration phase of growth with an oxygen limitation but with sufficient nitrogen concentration to maintain cell growth. The sugary cassava extract supplemented with andiroba oil proved to be a potential substrate for PHA MCL production.

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INTRODUÇÃO: O significado clínico das variantes histológicas da glomeruloesclerose segmentar e focal primária (GESF) ainda é pouco claro. Com o objetivo de determinar a frequência das variantes da GESF e sua evolução clínica em uma população hispânica, analisamos nossos casos desta glomerulopatia. MÉTODOS: Neste estudo retrospectivo, biópsias renais com diagnóstico de GESF (de 1998 a 2009) foram analisadas e classificadas acordo com os critérios da classificação de Columbia. Os dados clínico-evolutivos foram analisados e comparados entre as variantes. RESULTADOS: Do total de 291 casos, 224 (77,0%) corresponderam a variante sem especificação (NOS), 40 casos (13,7%) a forma com lesão no polo urinário (TIP), 14 casos (4,8%) a lesão perihiliar (PH), 10 casos (3,4%) ao tipo colapsante (COLL) e três casos (1,0%) a variante celular (CEL). A idade média de apresentação foi de 26 anos (intervalo de 1 a 79), sendo 74 pacientes (25,4%) com idade inferior a 15 anos. Hipertensão arterial e disfunção renal foram os achados mais frequentes nos casos de PH e COLL. A variante PH apresentou-se, frequentemente, com proteinúria não nefrótica. Notou-se menos lesões histológicas de cronicidade em casos TIP. Houve remissão clínica em 57% dos pacientes com TIP, 23,5% dos pacientes com NOS, 22,2% dos pacientes com COLL e em nenhum paciente com PH (p < 0,01). Doença renal crônica (DRC) foi menos frequente no grupo TIP comparativamente as outras variantes (p = 0,03). Não houve diferença estatística na evolução para estágio final da doença renal entre as variantes. CONCLUSÕES: A aparência histológica não parece ser um bom marcador clínico de prognóstico na GESF. A forma COLL é uma doença com muitas diferenças para as outras variantes e pior prognóstico. A variante PH ocorre principalmente de adultos, com evolução frequente para DRC. A lesão do tipo TIP parece ser menos agressiva que as outras variantes, embora sua evolução não seja benigna.

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Objetivo: Descrever quadro clínico-laboratorial de glomeruloesclerose segmentar e focal (GESF) subtipo colapsante em associação com infecção por parvovírus B19 (PVB19). Relato do caso: Paciente feminino, 37 anos, parda, iniciou quadro de faringoalgia e febre aferida com melhora parcial após penicilina. Com uma semana, observou redução de débito urinário e edema de membros inferiores. Tabagista, com histórico familiar e pessoal negativos para hipertensão, diabetes ou nefropatias. À admissão, apresentava-se com oliguria, hipertensão e edema, associados à anemia microcítica e hipocrômica hipoproliferativa, proteinúria nefrótica, hematúria microscópica e alteração da função renal. A investigação reumatológica e sorologias para hepatites e HIV foram negativas. Ultrassonografia de rins e vias urinárias sem alterações. PCR foi positivo para PVB19 em aspirado de medula óssea e sangue. A biópsia renal conclusiva de GESF subtipo colapsante. Ocorreu remissão espontânea com duas semanas do quadro. Em retorno ambulatorial, o PCR em sangue periférico foi negativo para PVB19, sugerindo associação de GESF colapsante a fase aguda ou reativação da infecção viral. Conclusão : Este relato registra a associação temporal entre GESF colapsante e viremia pelo PVB19, seja por infecção aguda ou reativação de infecção latente. A associação GESF colapsante e PVB19 é descrita na literatura, com demonstração da presença do vírus em tecido renal, porém, a real relação do vírus na patogênese dessa glomerulopatia permanece indefinida.

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Resumo Introdução: O perfil clínico de pacientes brasileiros adultos com síndrome nefrótica por doença de lesões mínimas (LM) e glomeruloesclerose segmentar e focal (GESF) é pouco conhecido. Objetivo: Avaliamos as características clínico-laboratoriais e resposta a tratamento em pacientes adultos com síndrome nefrótica e diagnósticos histológicos de LM ou GESF. Métodos: Fez-se a análise retrospectiva de 50 pacientes adultos com LM e 120 com GESF. Todos os pacientes foram inicialmente tratados com corticosteroide. Os desfechos do estudo foram: resposta a corticosteroide, prevalência de remissão total, progressão para doença renal crônica estágio 5 (DRC5) e necessidade de terapia de substituição renal por DRC5. Resultados: Níveis iniciais de creatinina sérica foram 24% mais elevados entre pacientes com GESF (p = 0,02) e os de proteinúria foram 36% mais altos em LM (p < 0,001). Pacientes com LM foram córtico-sensíveis em 80% dos casos, com remissão total em 74%, e os pacientes com GESF em 58% (p = 0,01), com remissão total em 30% (p = 0,002). A prevalência de insuficiência renal aguda em pacientes com GESF foi de 39% (vs. 12%, p = 0,013) e DRC5 de 10% (vs. 0%, p < 0,001). Remissão completa ou parcial com o uso de corticosteroide reduziu em 83% o risco de DRC5 (p < 0,001) e remissão total associou-se a redução no risco de DRC5 de 89% (p < 0,001). Conclusão: A resposta positiva à corticoterapia foi o fator mais importante relacionado à preservação da função renal ao longo de mais de uma década de seguimento, e GESF relacionou-se a menor índice de resposta a corticosteroide.