Construction and validation of metagenomic DNA libraries from landfarm soil microorganisms.

Landfarming biodegradation is a strategy used by the petrochemical industry to reduce pollutants in petroleum-contaminated soil. We constructed 2 metagenomic libraries from landfarming soil in order to determine the pathway used for mineralization of benzene and to examine protein expression of the bacteria in these soils. The DNA of landfarm soil, collected from Ilhéus, BA, Brazil, was extracted and a metagenomic library was constructed with the Copy Control(TM) Fosmid Library Production Kit, which clones 25-45-kb DNA fragments. The clones were selected for their ability to express enzymes capable of cleaving aromatic compounds. These clones were grown in Luria-Bertani broth plus L-arabinose, benzene, and chloramphenicol as induction substances; they were tested for activity in the catechol cleavage pathway, an intermediate step in benzene degradation. Nine clones were positive for ortho-cleavage and one was positive for meta-cleavage. Protein band patterns determined by SDS-polyacrylamide gel electrophoresis differed in bacteria grown on induced versus non-induced media (Luria-Bertani broth). We concluded that the DNA of landfarm soil is an important source of genes involved in mineralization of xenobiotic compounds, which are common in gasoline and oil spills. Metagenomic library allows identification of non-culturable microorganisms that have potential in the bioremediation of contaminated sites.

Rapid sample preparation procedure for As speciation in food samples by LC-ICP-MS.

This paper describes a rapid method for arsenic (As) speciation by LC-ICP-MS in several types of food samples. Prior to analysis, samples were milled and the As species extracted from biological tissues by sonication in only 2 min with a solution containing MeOH (10%, v/v) plus HNO3 (2%, v/v). As species were separated by LC using an anion exchange column. Method detection limits for AsB, As³âº, DMA, MMA and As5⁺ were 1.3, 0.9, 0.6, 0.7 and 0.8 ng g⁻¹, respectively. Method accuracy and precision were traceable to Certified Reference Materials SRM1577 bovine liver from the National Institute of Standards and Technology, CE278 mussel tissue from the Institute of Reference Materials and Measurements and DOLT-3 dogfish liver tissue and DORM-3 fish protein from the National Research Council of Canada. Finally, the method was applied to speciate As in food samples (egg, fish muscle, beef and chicken) purchased in Brazilian markets.

[Malaria in the region of Campinas, São Paulo, Brazil, 1980 to 1994]. / Malária na região de Campinas, São Paulo, Brasil, 1980 a 1994.

According to epidemiological data, from 1980 to 1994, 2,781 cases of malaria were registered as follows: DIR XII-Campinas (49.3%), DIR XV-Piracicaba (41.3%) and DIR XX-São João da Boa Vista (9.4%). The Plasmodium vivax was found in 70.6% of the patients; Plasmodium falciparum in 25.4% and 4% of the patients presented a mixed infection. The epidemiological classification showed that 95% of the cases came from the States of Rondônia, Mato Grosso and Par. The masculine sex, between the age of 20 to 39 years old, was responsible for 84.3% of the confirmed cases. During the study period, 9 cases of induced malaria were registered: 5 of which through blood transfusion, 3 through the sharing of syringes and infected needles among drug users and one occurrence of congenital malaria. 5 deaths were registered in patients prime-infected by Plasmodium falciparum with late diagnosis. The set of variables studied enabled a greater understanding of the epidemiology of malaria in the region and to subsidize and indicate the process of decentralization of attendance, diagnosis and treatment of the patient, as well as the control and epidemiological surveillance of the endemic disease in Campinas region and in the State of São Paulo.

[The teaching of primary health care: diagnostic and educational evaluation by microcomputers]. / O ensino de atenção primária à saúde: avaliação diagnóstica e formativa através de microcomputadores.

The study aims to explore the utilization of the Formative Evaluation by the microcomputer in the teaching of primary attention to the health. The experiment is composed of eight modules, programmed in Basic software "Formative Evaluation". For each module, a "Question Bank" with three sorts of feedbacks was organized. The sample includes 16 subjects. The results show that the Formative Evaluation by Microcomputer proportioned to the students a cognitive domain significantly higher than the traditional instruction. However, it didn't provide a significantly superior performance to the students who experienced this system.