RESUMO
A combined molecular and cultural method for the detection of the Mycobacterium tuberculosis complex (MTBC) and Mycobacterium avium subsp. paratuberculosis was developed and tested with artificially contaminated milk and dairy products. Results indicate that the method can be used for a reliable detection as a basis for first risk assessments.
Assuntos
Laticínios/microbiologia , Microbiologia de Alimentos/métodos , Mycobacterium avium subsp. paratuberculosis/isolamento & purificação , Mycobacterium tuberculosis/isolamento & purificação , Animais , Técnicas Bacteriológicas , Técnicas de Cultura de Células , DNA Bacteriano/análise , Leite/microbiologia , Mycobacterium avium subsp. paratuberculosis/genética , Mycobacterium tuberculosis/genética , Reação em Cadeia da Polimerase , Medição de RiscoRESUMO
In this study, 809 samples of ice cream from different sources were investigated by using cultural methods for the presence of presumptive Bacillus cereus. Isolates from culture-positive samples were examined with a real-time PCR assay targeting a region of the cereulide synthetase gene (ces) that is highly specific for emetic B. cereus strains. The samples were collected from ice cream parlors and restaurants that produced their own ice cream and from international commercial ice cream companies in different regions of Bavaria during the summer of 2008. Presumptive B. cereus was found in 508 (62.7%) ice cream samples investigated, and 24 (4.7%) of the isolates had the genetic background for cereulide toxin production. The level of emetic B. cereus in the positive samples ranged from 0.1 to 20 CFU/g of ice cream.
Assuntos
Bacillus cereus/isolamento & purificação , Eméticos/metabolismo , Contaminação de Alimentos/análise , Sorvetes/microbiologia , Contagem de Colônia Microbiana , Depsipeptídeos/metabolismo , Microbiologia de Alimentos , Alemanha , Ligases/genética , Reação em Cadeia da Polimerase , Prevalência , Especificidade da EspécieRESUMO
BACKGROUND: Leptin has been shown to regulate food intake and energy expenditure. Very recently, associations of elevated leptin plasma levels during alcohol withdrawal with alcohol craving have been observed in humans. Therefore, we tested the hypothesis that the application of exogenous leptin modulates voluntary alcohol consumption in mice. METHODS: Sixteen mice (129/Sv x C57BL/6J) were habituated to ethanol consumption over a time period of 3 months. After a basal 2-week free-choice drinking phase, mice were separated into two groups (n = 8) according to weight and alcohol consumption. They received recombinant leptin (1 mg/kg) versus saline intraperitoneally daily for 10 days. After 4 days of free-choice consumption of ethanol (16% v/v) versus water, ethanol was withdrawn at day 4 and replaced at day 6 to test the occurrence of an alcohol deprivation effects. Fluid intake was evaluated by controlling the weight of the drinking tubes daily. RESULTS: Free-choice ethanol consumption after withdrawal was significantly elevated in mice after intraperitoneal injection of 1 mg/kg leptin (alcohol deprivation effect), but not during basal drinking. CONCLUSION: We suggest that leptin may enhance motivation for alcohol consumption in habituated mice after alcohol withdrawal.