Comparação de configurações para leitura de potássio em ICP-OES.

O objetivo do trabalho foi comparar diferentes configurações do ICP-OES na determinação da concentração de K, em amostras de tecido vegetal, buscando reduzir o tempo de leitura das amostras e, consequentemente, o custo operacional do equipamento

Primary Effusion Lymphoma in a HIV Infected Patient

O linfoma primário das cavidades é um subtipo de linfoma não-Hodgkin (LNH), de ocorrência rara, prognóstico muito reservado, mais frequentemente descrito em indivíduos imunodeprimidos, em particular no contexto de infecção pelo vírus da imunodeficiência humana (VIH), no qual as células malignas proliferam exclusivamente nas cavidades serosas e que está associado ao vírus herpes humano tipo 8 (VHH8). Os autores apresentam o caso de um doente com infecção VIH, internado por febre e queixas constitucionais e que desenvolveu, enquanto decorria estudo etiológico da síndrome febril, ascite volumosa e, ainda, derrame pleural direito e derrame pericárdico. O líquido ascítico mostrou a presença de células grandes linfóides com fenótipo não B e não T. Não foram evidenciadas massas tumorais, linfadenopatias ou envolvimento da medula óssea. O doente morreu 41 dias após o diagnóstico, sem ter iniciado quimioterapia. Ainda que não tenha sido possível a demonstração de infecção pelo VHH-8 nas células linfóides, os dados clínicos, citológicos e imunofenotípicos apontam para um diagnóstico altamente provável de linfoma primário das cavidades

Monte Carlo simulation of uncoupled continuous-time random walks yielding a stochastic solution of the space-time fractional diffusion equation

We present a numerical method for the Monte Carlo simulation of uncoupled continuous-time random walks with a Levy alpha-stable distribution of jumps in space and a Mittag-Leffler distribution of waiting times, and apply it to the stochastic solution of the Cauchy problem for a partial differential equation with fractional derivatives both in space and in time. The one-parameter Mittag-Leffler function is the natural survival probability leading to time-fractional diffusion equations. Transformation methods for Mittag-Leffler random variables were found later than the well-known transformation method by Chambers, Mallows, and Stuck for Levy alpha-stable random variables and so far have not received as much attention; nor have they been used together with the latter in spite of their mathematical relationship due to the geometric stability of the Mittag-Leffler distribution. Combining the two methods, we obtain an accurate approximation of space- and time-fractional diffusion processes almost as easy and fast to compute as for standard diffusion processes.Comment: 7 pages, 5 figures, 1 table. Presented at the Conference on Computing in Economics and Finance in Montreal, 14-16 June 2007; at the conference "Modelling anomalous diffusion and relaxation" in Jerusalem, 23-28 March 2008; et

Evaluating adherence to highly active antiretroviral therapy with use of pill counts and viral load measurement in the drug resources enhancement against AIDS and malnutrition program in Mozambique

Background. Maintaining treatment adherence among the growing number of patients receiving antiretroviral treatment in Africa is a dramatic challenge. The objective of our study was to explore the results of a computerized pill count method and to test the validity, sensitivity, and specificity of this method with respect to viral load measurement in an African setting. Methods. We performed a prospective, observational study involving patients who received first-line highly active antiretroviral therapy in Mozambique from 1 April 2005 through 31 March 2006. Enrolled patients had received treatment for at least 3 months before the study. For defining treatment adherence levels, pill counts were used, and the results were analyzed with viral load measurements at the end of the observation period. Results. The study involved 531 participants. During the 12 months of observation, 137 patients left the program or discontinued first-line therapy. Of the remaining 394 patients, 284 (72.1%) had >95% treatment adherence; of those 284 patients, 274 (96.5%) had a final viral load <1000 copies/mL. A Cox proportional hazards analysis revealed that the relationship between >95% treatment adherence and the final viral load was closer than that between >90% treatment adherence and viral load. Conclusions. Treatment adherence >95% maximizes the results of the nonnucleoside reverse-transcriptase inhibitor-based regimen. The pill count method appears to be a reliable and economic tool for monitoring treatment adherence in resource-limited settings

Evaluating adherence to highly active antiretroviral therapy with use of pill counts and viral load measurement in the drug resources enhancement against AIDS and malnutrition program in Mozambique

Background. Maintaining treatment adherence among the growing number of patients receiving antiretroviral treatment in Africa is a dramatic challenge. The objective of our study was to explore the results of a computerized pill count method and to test the validity, sensitivity, and specificity of this method with respect to viral load measurement in an African setting. Methods. We performed a prospective, observational study involving patients who received first-line highly active antiretroviral therapy in Mozambique from 1 April 2005 through 31 March 2006. Enrolled patients had received treatment for at least 3 months before the study. For defining treatment adherence levels, pill counts were used, and the results were analyzed with viral load measurements at the end of the observation period. Results. The study involved 531 participants. During the 12 months of observation, 137 patients left the program or discontinued first-line therapy. Of the remaining 394 patients, 284 (72.1%) had >95% treatment adherence; of those 284 patients, 274 (96.5%) had a final viral load <1000 copies/mL. A Cox proportional hazards analysis revealed that the relationship between >95% treatment adherence and the final viral load was closer than that between >90% treatment adherence and viral load. Conclusions. Treatment adherence >95% maximizes the results of the nonnucleoside reverse-transcriptase inhibitor-based regimen. The pill count method appears to be a reliable and economic tool for monitoring treatment adherence in resource-limited settings