Growth and mortality estimates of Sardinella brasiliensis in the southeastern Brazilian Bight

Length frequency analisys were applied for sardine data collected from commercial catches throughout the southeastern Brazilian coast in 1977-1987. Age/length keys were obtained by otolith ring countings and utilized to transform length into age composition. Growth parameters were estimated by the von Bertalanffy growth equation using age and length data for each year and for all the period of investigation. The mean growth parameters for the entire period were estimated as L∞ = 271 mm and K= 0.59 year-1. Instantaneous total mortality (Z) coefficients per year were estimated using catch curves and methods based on the mean length of the fish caught. Total mortality rate for the entire period was obtained through the average of the annual values. Natural mortality (M) was estimated using the Paul/s empirical equation (1980a), and fishing mortality (F) by the difference between total and natural mortality values.The results were Z = 3.6 year-1; M = 0.96 year-1; and F= 2.6 year-1.Estudo sobre o crescimento e a mortalidade de Sardinella brasiliensis, da costa sudeste do Brasil, foi realizado para o período 1977 a 1987. As análises foram efetuadas a partir de dados existentes sobre distribuições de freqüência de comprimento de amostras da captura comercial. Chaves idade/comprimento, construidas a partir de leitura de anéis de crescimento em otólitos, dentro do Programa Integrado de Estudos Biológicos sobre a Sardinha - PIEBS, foram utilizadas para transformar as distribuiçes de comprimento em idade. Os parâmetros de crescimento da equação de von Bertalanffy foram estimados, anualmente e para o período como um todo, a partir de métodos que utilizam dados de idade e comprimento. Os parâmetros médios encontrados para o período foram: L∞ = 271 mm e K= 0,59 ano-1. Os coeficientes instantâneos de mortalidade total (Z) anuais foram calculados pelas curvas de captura e por métodos baseados no comprimento médio dos indivíduos nas capturas. A mortalidade total para todo o período foi obtida pela média dos valores anuais. O coeficiente instantâneo de mortalidade natural (M) foi estimado pela equação empírica de Pauly (1980a), usando um fator de correção de 0,8 para clupeoides, e o coeficiente instantâneo de mortalidade por pesca (F), pela diferença entre a mortalidade total e a natural. Os valores encontrados foram: Z= 3,6 ano-1, M = 0,96 ano-1 e F= 2,6 ano-1

Detection of multidrug-resistant tuberculosis from stored DNA samples : a multicenter study

Background: In low-income countries, rapid detection of tuberculosis (TB) drug resistance is often restricted by the difficulties of transporting and storing sputum samples from remote health centers to the reference laboratories where molecular tests are available. The aim of this study was to evaluate the performance of four transport and storage systems for molecular detection of rifampicin (RIF) and isoniazid (INH) resistance. Methods: This was a multicenter study. Molecular detection of RIF and INH resistance was performed directly from smear-positive TB sputa spotted on a slide, FTA card, GenoCard, and ethanol using the Genotype MTBDRplus assay. The performance of the DNA extraction method from each storage support to detect drug resistance was assessed by calculating their sensitivity and specificity compared to the phenotypic method. Results: From all sites, the overall sensitivity and specificity for RIF-resistance detection was 88% and 85%, respectively, for slides, 86% and 92%, respectively, for GenoCard, 87% and 89%, respectively, for FTA card, and 88% and 92%, respectively, for ethanol. For INH-resistance detection, the overall sensitivity and specificity was 82% and 90%, respectively, for slides, 85% and 96%, respectively, for GenoCard, 86% and 92%, respectively, for FTA card, and 86% and 94%, respectively, for ethanol. Conclusion: Smear slides and filter cards showed to be very useful tools to facilitate DNA extraction from sputum samples with the potential to accelerate the detection of drug resistance in remote areas

Nosocomial Bloodstream Infections in Brazilian Hospitals: Analysis of 2,563 Cases from a Prospective Nationwide Surveillance Study▿

Nosocomial bloodstream infections (nBSIs) are an important cause of morbidity and mortality. Data from a nationwide, concurrent surveillance study, Brazilian SCOPE (Surveillance and Control of Pathogens of Epidemiological Importance), were used to examine the epidemiology and microbiology of nBSIs at 16 Brazilian hospitals. In our study 2,563 patients with nBSIs were included from 12 June 2007 to 31 March 2010. Ninety-five percent of BSIs were monomicrobial. Gram-negative organisms caused 58.5% of these BSIs, Gram-positive organisms caused 35.4%, and fungi caused 6.1%. The most common pathogens (monomicrobial) were Staphylococcus aureus (14.0%), coagulase-negative staphylococci (CoNS) (12.6%), Klebsiella spp. (12.0%), and Acinetobacter spp. (11.4%). The crude mortality was 40.0%. Forty-nine percent of nBSIs occurred in the intensive-care unit (ICU). The most frequent underlying conditions were malignancy, in 622 patients (24.3%). Among the potential factors predisposing patients to BSI, central venous catheters were the most frequent (70.3%). Methicillin resistance was detected in 157 S. aureus isolates (43.7%). Of the Klebsiella sp. isolates, 54.9% were resistant to third-generation cephalosporins. Of the Acinetobacter spp. and Pseudomonas aeruginosa isolates, 55.9% and 36.8%, respectively, were resistant to imipenem. In our multicenter study, we found high crude mortality and a high proportion of nBSIs due to antibiotic-resistant organisms