A continuidade do uso de anfetaminas por motoristas de caminhão no Estado de São Paulo, Brasil, a despeito da proibição de sua produção, prescrição e uso

O uso de anfetaminas por motoristas de caminhão com fins ocupacionais é amplamente reconhecido, entretanto, no mês de outubro de 2011, sua produção e uso foram proibidos através de uma resolução da Agência Nacional de Vigilância Sanitária (ANVISA). O objetivo deste estudo foi identificar o uso de anfetaminas entre motoristas de caminhão após a implementação da referida resolução. Uma amostra de conveniência de 427 motoristas de caminhão foi abordada em rodovias do Estado de São Paulo, Brasil, durante o ano de 2012. Os participantes foram solicitados a responder um instrumento de pesquisa estruturado, assim como fornecer uma amostra de urina para avaliar o uso recente de anfetaminas através de análise toxicológica. Entre os motoristas avaliados, 7% fizeram uso recente de alguma substância ilícita, dos quais 2,7% usaram anfetaminas. Aparte a periculosidade associada ao uso de anfetaminas, assim como a despeito da resolução que o regulamenta, esse uso continua entre os motoristas de caminhão. Assim, sugere-se que as autoridades competentes fiscalizem a posse, assim como o uso de anfetaminas no contexto do trânsito

Binding of lac repressor-GFP fusion protein to lac operator sites inserted in the tobacco chloroplast genome examined by chromatin immunoprecipitation

Chromatin immunoprecipitation (ChIP) has been used to detect binding of DNA-binding proteins to sites in nuclear and mitochondrial genomes. Here, we describe a method for detecting protein-binding sites on chloroplast DNA, using modifications to the nuclear ChIP procedures. The method was developed using the lac operator (lacO)/lac repressor (LacI) system from Escherichia coli. The lacO sequences were integrated into a single site between the rbcL and accD genes in tobacco plastid DNA and homoplasmic transplastomic plants were crossed with transgenic tobacco plants expressing a nuclear-encoded plastid-targeted GFP-LacI fusion protein. In the progeny, the GFP-LacI fusion protein could be visualized in living tissues using confocal microscopy, and was found to co-localize with plastid nucleoids. Isolated chloroplasts from the lacO/GFP-LacI plants were lysed, treated with micrococcal nuclease to digest the DNA to fragments of ∼600 bp and incubated with antibodies to GFP and protein A-Sepharose. PCR analysis on DNA extracted from the immunoprecipitate demonstrated IPTG (isopropylthiogalactoside)-sensitive binding of GFP-LacI to lacO. Binding of GFP-LacI to endogenous sites in plastid DNA showing sequence similarity to lacO was also detected, but required reversible cross-linking with formaldehyde. This may provide a general method for the detection of binding sites on plastid DNA for specific proteins

Allergenicity assessment of genetically modified crops—what makes sense?

GM crops have great potential to improve food quality, increase harvest yields and decrease dependency on certain chemical pesticides. Before entering the market their safety needs to be scrutinized. This includes a detailed analysis of allergenic risks, as the safety of allergic consumers has high priority. However, not all tests currently being applied to assessing allergenicity have a sound scientific basis. Recent events with transgenic crops reveal the fallacy of applying such tests to GM crops

Mexican oregano essential oils as alternatives to butylated hydroxytoluene to improve the shelf life of ground beef

Oregano essential oils from Lippia berlandieri Schauer (Lb) and Poliomintha longiflora Gray (Pl) were tested against the antioxidant butylated hydroxytoluene (Bht) to evaluate effects on the shelf life of ground beef (GB) over 7 days of storage at 4°C. The treatments were GB1 = GB control, GB2 = GB +100 mg/kg of Bht, GB3 = GB +100 mg/kg of Lb, and GB4 = GB +100 mg/kg of Pl. Lightness, redness, hardness, and springiness showed differences (p < .05) between treatments and days interaction, which serve as indicators of ground beef preserved quality and consumer acceptance. Mesophilic, psychrophilic, and lactic acid bacteria numbers and antioxidant activity showed differences (p < .05) for treatments and days. Sensory attributes showed no differences between treatments. The oregano oils may provide extended shelf life for packaged meat products treated with these natural additives and hence may be used for ground beef preservation