Avaliação da Dispersão de o3 Troposférico na RMSP Utilizando CIT e mm5

Avaliação da dispersão de O3 troposférico na RMSPutilizando CIT e MM

Valor nutricional da silagem pré-secada de capim Tifton - 85

A conservação de volumosos é estratégia que visa manter a qualidade nutricional das forrageiras e diminuir suas perdas, para que essas possam ser fornecidas aos animais em épocas desfavoráveis, onde geralmente existe baixa quantidade ou qualidade dos alimentos disponíveis nas propriedades. Nessa pesquisa foi avaliado se a silagem pré-secada de capim Tifton-85 (Cynodon spp.) com 60% de matéria seca mantém o valor nutricional durante o armazenamento. Os tratamentos avaliados consistiram nos tempos de armazenamento 1, 3, 7, 14, 28 e 56 dias. O delineamento utilizado foi blocos ao acaso. Não foram observadas diferenças (p>0,05) para as variáveis: matéria pré-seca, proteína bruta, extrato etéreo, fibra em detergente neutro, lignina e digestibilidade in vitro da matéria seca. Houve variação (p<0,05) no teor de fibra em detergente ácido que aumentou aos 28 dias. A hemicelulose apresentou comportamento contrário, reduzindo (p<0,05) suas concentrações 14 dias após a ensilagem. Foram observadas diferenças (p<0,05) para pH que decresceu enquanto o nitrogênio amoniacal apresentou aumento (p<0,05) até o último tempo de armazenamento avaliado. Não foram verificadas diferenças nos teores de micotoxinas entre planta e silagem aos 56 dias. Conclui-se que a silagem pré-secada de capim Tifton-85 (Cynodon spp.) mantem seus valores nutricionais durante o tempo de armazenamento avaliado, tendo seus melhores índices nutritivos a partir dos 28 dias de produção

Identification of Mycobacterium tuberculosis complex based on amplification and sequencing of the oxyR pseudogene from stored Ziehl-Neelsen-stained sputum smears in Brazil

A cross-sectional analysis of stored Ziehl-Neelsen (ZN)-stained sputum smear slides (SSS) obtained from two public tuberculosis referral laboratories located in Juiz de Fora, Minas Gerais, was carried out to distinguish Mycobacterium bovis from other members of the Mycobacterium tuberculosis complex (MTC). A two-step approach was used to distinguish M. bovis from other members of MTC: (i) oxyR pseudogene amplification to detect MTC and, subsequently, (ii) allele-specific sequencing based on the polymorphism at position 285 of this gene. The oxyR pseudogene was successfully amplified in 100 of 177 (56.5%) SSS available from 99 individuals. No molecular profile of M. bovis was found. Multivariate analysis indicated that acid-fast bacilli (AFB) results and the source laboratory were associated (p < 0.05) with oxyR pseudogene amplification. SSS that were AFB++ SSS showed more oxyR pseudogene amplification than those with AFB0, possibly due to the amount of DNA. One of the two source laboratories presented a greater chance of oxyR pseudogene amplification, suggesting that differences in sputum conservation between laboratories could have influenced the preservation of DNA. This study provides evidence that stored ZN-SSS can be used for the molecular detection of MTC

A comparison of mycolic acid analysis for nontuberculous mycobacteria identification by thin-layer chromatography and molecular methods

The development of fast, inexpensive, and reliable tests to identify nontuberculous mycobacteria (NTM) is needed. Studies have indicated that the conventional identification procedures, including biochemical assays, are imprecise. This study evaluated a proposed alternative identification method in which 83 NTM isolates, previously identified by conventional biochemical testing and in-house M. avium IS1245-PCR amplification, were submitted to the following tests: thin-layer chromatography (TLC) of mycolic acids and PCR-restriction enzyme analysis of hsp65 (PRA). High-performance liquid chromatography (HPLC) analysis of mycolic acids and Southern blot analysis for M. avium IS1245 were performed on the strains that evidenced discrepancies on either of the above tests. Sixty-eight out of 83 (82%) isolates were concordantly identified by the presence of IS1245 and PRA and by TLC mycolic acid analysis. Discrepant results were found between the phenotypic and molecular tests in 12/83 (14.4%) isolates. Most of these strains were isolated from non-sterile body sites and were most probably colonizing in the host tissue. While TLC patterns suggested the presence of polymycobacterial infection in 3/83 (3.6%) cultures, this was the case in only one HPLC-tested culture and in none of those tested by PRA. The results of this study indicated that, as a phenotypic identification procedure, TLC mycolic acid determination could be considered a relatively simple and cost-effective method for routine screening of NTM isolates in mycobacteriology laboratory practice with a potential for use in developing countries. Further positive evidence was that this method demonstrated general agreement on MAC and M. simiae identification, including in the mixed cultures that predominated in the isolates of the disseminated infections in the AIDS patients under study. In view of the fact that the same treatment regimen is recommended for infections caused by these two species, TLC mycolic acid analysis may be a useful identification tool wherever molecular methods are unaffordable