Characterization of Listeria monocytogenes isolates of food and human origins from Brazil using molecular typing procedures and in vitro cell culture assays.

The spreading of diseases through foods is a worldwide concern. Here, molecular and in vitro cell-culture assays were employed to characterize 63 Brazilian Listeria monocytogenes isolates (food, 47; clinical, 16). Serotype 4b was the most predominant (49%) followed by (1/2)b (30%), (1/2)a (10%), (1/2)c (6%), 3c (3%) and 3b (2%). Ribotyping yielded 17 ribopatterns, which were grouped into four phylogenetic clusters. Cluster A comprised of 39/63 isolates primarily of food origin, and clusters B, C and D contained both food and clinical isolates. Isolates were positive for virulence determinants prfA, hlyA and inlA: clinical isolates were more invasive to Caco-2 cells and expressed high levels of inlA transcripts than the food isolates. Highly invasive isolates also provoked more Ped-2E9 cells to die by apoptosis than the weakly-invasive strains. These data demonstrate a strong genetic relatedness among clinical and food isolates and suggest transmission of a subset of L. monocytogenes strains from food to humans.

Salmonella sp. in normal and condemned heart and liver from broiler slaughtered in Goias state and identification of susceptibility to antimicrobial agents / Salmonella sp. em corações e fígados normais e condenados de frangos de corte abatidos no estado de Goiás e identificação da suscetibilidade a antimicrobianos

Salmonella is hazard to food safety. This study investigated the presence of Salmonella sp in normal and condemned heart and liver samples from broilers. These specimens were subdivided into pools of five samples, which were processed according to the recommend procedure by Brazilian legislation. A total of 9.24% of these pools were Salmonella positive, which corresponded to 5.41% of normal hearts and 25.00% of condemned livers. Salmonella Enteritidis was isolated from two normal heart pools and seven condemned livers pools. Of these positive samples, Salmonella Typhimurium was isolated from two pools. The isolated strains were tested for antimicrobial susceptibility profile to thirteen antimicrobial agents. Of two Salmonella Enteritidis strains isolated from normal hearts, one showed resistance to one of the tested antimicrobial drugs. The other strain was susceptible to all the tested antimicrobial drugs. This bacterium sorovar isolated from condemned livers was susceptible to all of the evaluated antimicrobial drugs. Salmonella Typhimurium was isolated from two pools, which showed concomitant resistance to four antimicrobials agents. The other strain showed to be sensitive to all of the tested drugs. These data show that chicken giblets, which are commonly available in markets, could be a source for Salmonella sp transmission. It might represent a risk to public health as th

Salmonella sp. constitui ameaça à segurança do alimento. Este estudo verificou a ocorrência de Salmonella sp. em amostras de corações e fígados normais e condenados. As amostras em análise foram subdivididas em pools de cinco e processadas pelo método bacteriano convencional, preconizado pela legislação. Do total de pools, 9,24% foram Salmonella positivos, correspondendo a 5,41% de corações normais e 25% de fígados condenados. Salmonella Enteritidis foi isolada em dois pools de corações normais e em sete pools de fígados condenados. Nesta categoria de amostras, houve o isolamento de Salmonella Typhimurium em dois pools, porém negativo em amostras de corações normais e condenados e fígados normais. As cepas isoladas foram avaliadas quanto ao perfil de suscetibilidade a treze agentes antimicrobianos. Das duas cepas de Salmonella Enteritidis isoladas de amostras de corações normais, uma apresentou resistência a um princípio ativo. A outra cepa foi sensível a todos os antimicrobianos. As cepas do sorovar isolado de fígados condenados apresentaram sensibilidade para todos os antimicrobianos avaliados. SalmonellaTyphimurium foi isolada em dois pools, em que uma cepa apresentou resistência concomitantemente a quatro drogas antimicrobianas. A outra cepa mostrou-se sensível a todos os antimicrobianos testados. Os miúdos de frangos, comumente comercializados, podem representar risco à sa