Application of the bacteriophage Mu-driven system for the integration/amplification of target genes in the chromosomes of engineered Gram-negative bacteria—mini review

The advantages of phage Mu transposition-based systems for the chromosomal editing of plasmid-less strains are reviewed. The cis and trans requirements for Mu phage-mediated transposition, which include the L/R ends of the Mu DNA, the transposition factors MuA and MuB, and the cis/trans functioning of the E element as an enhancer, are presented. Mini-Mu(LR)/(LER) units are Mu derivatives that lack most of the Mu genes but contain the L/R ends or a properly arranged E element in cis to the L/R ends. The dual-component system, which consists of an integrative plasmid with a mini-Mu and an easily eliminated helper plasmid encoding inducible transposition factors, is described in detail as a tool for the integration/amplification of recombinant DNAs. This chromosomal editing method is based on replicative transposition through the formation of a cointegrate that can be resolved in a recombination-dependent manner. (E-plus)- or (E-minus)-helpers that differ in the presence of the trans-acting E element are used to achieve the proper mini-Mu transposition intensity. The systems that have been developed for the construction of stably maintained mini-Mu multi-integrant strains of Escherichia coli and Methylophilus methylotrophus are described. A novel integration/amplification/fixation strategy is proposed for consecutive independent replicative transpositions of different mini-Mu(LER) units with “excisable” E elements in methylotrophic cells

Infecção pelo HIV durante a gestação: estudo-Sentinela Parturiente, Brasil, 2002 HIV infection during pregnancy: the Sentinel Surveillance Project, Brazil, 2002

OBJETIVO: Avaliar a cobertura efetiva da detecção da infecção pelo HIV durante a gestação, em âmbito nacional. MÉTODOS: A cobertura efetiva do teste de HIV na gestação foi definida como a proporção de gestantes que teve atendimento pré-natal (pelo menos uma consulta), pedido de teste de HIV e conhecimento do resultado antes do parto, sendo estimada por processo de amostragem, utilizando-se as informações coletadas no Estudo-Sentinela Parturiente, 2002. As desigualdades da cobertura efetiva foram analisadas por: grande região; tamanho populacional do município de ocorrência do parto; e grau de instrução da mãe. RESULTADOS: A cobertura efetiva do teste de HIV durante a gestação foi estimada em 52%. As enormes desigualdades socioespaciais ficaram evidenciadas na comparação entre as regiões Nordeste (24%) e Sul (72%); entre parturientes analfabetas (19%) com as que têm o ensino fundamental completo (64%); entre as que realizaram o parto em municípios pequenos (36%) com as que o realizaram em municípios com mais de 500 mil habitantes (66%). As recomendações do Ministério da Saúde foram atendidas, completamente, por somente 27% parturientes. CONCLUSÕES: Os resultados estabelecem a necessidade de haver medidas voltadas para maior cobertura da detecção do HIV na gestação, e indicam que os programas do Programa Nacional de DST e Aids e os programas de saúde da mulher devem ser intensificados, com estratégias conjuntas entre eles.<br>OBJECTIVE: To evaluate the actual coverage of HIV infection detection during pregnancy at national level. METHODS: The actual coverage of HIV testing during pregnancy was defined as the proportion of women who attended prenatal care visits (at least one visit), ordering HIV testing and knowledge of test result before delivery. The coverage was estimated by sampling procedures based on the 2002 Sentinel Surveillance Study data. Actual coverage Inequalities were assessed by: country regions; population size of the municipality where delivery took place; and mother's schooling. RESULTS: The actual coverage of HIV testing during pregnancy was 52%. Huge sociogeographic inequalities are seen between the Northeastern (24%) and Southern regions (72%); illiterate mothers (19%) and those with complete basic education (64%); mothers who delivered in small municipalities (36%) and those who delivered in municipalities with more than 500,000 inhabitants (66%). Ministry of Health recommendations were fully followed by only 27% pregnant women. CONCLUSIONS: The study results show a need for actions aiming at increasing HIV detection coverage during pregnancy, and indicate that HIV/STD programs should be intensified with joint strategies between the National AIDS Program and infant-maternal programs