RESUMO
UNLABELLED: This study aimed to assess the microbiological contamination of lettuces commercialized in Rio de Janeiro, Brazil, in order to investigate detection of norovirus genogroup II (NoV GII), Salmonella spp., total and fecal coliforms, such as Escherichia coli. For NoV detection samples were processed using the adsorption-elution concentration method associated to real-time quantitative polymerase chain reaction (qPCR). A total of 90 samples of lettuce including 30 whole fresh lettuces, 30 minimally processed (MP) lettuces, and 30 raw ready-to-eat (RTE) lettuce salads were randomly collected from different supermarkets (fresh and MP lettuce samples), food services, and self-service restaurants (RTE lettuce salads), all located in Rio de Janeiro, Brazil, from October 2010 to December 2011. NoV GII was not detected and PP7 bacteriophage used as internal control process (ICP) was recovered in 40.0%, 86.7%, and 76.7% of those samples, respectively. Salmonella spp. was not detected although fecal contamination has been observed by fecal coliform concentrations higher than 10(2) most probable number/g. E. coli was detected in 70.0%, 6.7%, and 30.0% of fresh, MP, and RTE samples, respectively. This study highlights the need to improve hygiene procedures at all stages of vegetable production and to show PP7 bacteriophage as an ICP for recovering RNA viruses' methods from MP and RTE lettuce samples, encouraging the evaluation of new protocols that facilitate the establishment of methodologies for NoV detection in a greater number of food microbiology laboratories. PRACTICAL APPLICATION: The PP7 bacteriophage can be used as an internal control process in methods for recovering RNA viruses from minimally processed and ready-to-eat lettuce samples.
Assuntos
Escherichia coli/crescimento & desenvolvimento , Fezes/microbiologia , Microbiologia de Alimentos , Lactuca/microbiologia , Norovirus/crescimento & desenvolvimento , Salmonella/crescimento & desenvolvimento , Animais , Brasil , Comércio , Fast Foods , Contaminação de Alimentos/análise , Manipulação de Alimentos/normas , Microbiologia de Alimentos/métodos , Humanos , Levivirus , Restaurantes , Verduras/microbiologiaRESUMO
AIM: The aim of this systematic review and meta-analysis was to assess and compare peri-implant marginal bone loss in cement- and screw-retained prostheses. MATERIAL AND METHODS: Electronic database and manual searches were undertaken to identify trials, prospective or retrospective studies reporting on radiographic marginal bone loss around dental implants restored with cement- and/or screw-retained prostheses. Two reviewers independently conducted the article selection and data extraction. Random-effects models were used to obtain estimates of peri-implant marginal bone loss [mean, 95% confidence intervals (CI)]. RESULTS: Of the 1217 identified studies, nine finally met the inclusion criteria. Only two studies included both cement- and screw-retained prostheses, three assessed only screw-retained prostheses, and four evaluated only cement-retained prostheses. Pooled mean marginal bone loss was 0.53 mm (CI 95%, 0.31-0.76 mm) for cement-retained prostheses and 0.89 mm (CI 95%, 0.45-1.33 mm) for screw-retained prostheses. CONCLUSION: There is no evidence to support differences in the marginal bone loss through indirect comparison between cement and screw-retained restorations.
Assuntos
Perda do Osso Alveolar/etiologia , Cimentação/métodos , Implantes Dentários , Retenção em Prótese Dentária/instrumentação , Prótese Dentária Fixada por Implante , Peri-Implantite/etiologia , Cimentos Dentários/química , Projeto do Implante Dentário-Pivô , Retenção em Prótese Dentária/métodos , HumanosRESUMO
BACKGROUND: The role of mitochondrial lesions in the pathogenesis of irreversible cellular ischemia is controversial. The inability to restore mitochondrial function is correlated with the inability to reverse cell damage in various tissues. The objective of the present study was to compare parameters associated with oxidative phosphorylation and the inner mitochondrial membrane potential of skeletal muscle of rats submitted to total ischemia in order to determine which mitochondrial alterations are mainly affected in this condition. MATERIAL AND METHODS: Wistar rats were submitted to 5 h total ischemia using the tourniquet method (ischemic limb group). The contralateral limb of each rat was used as control (control limb group). After the ischemic period, muscle biopsies were obtained for the isolation of the mitochondrial fractions, which were submitted to polarographic analysis for the determination of ADP-activated oxygen consumption (state 3), basal respiration (state 4), and the ratio of the two respiratory activities: the respiratory control ratio (RCR). The potential of the inner mitochondrial membrane was determined by measuring the fluorescence difference between coupled and uncoupled mitochondria using safranine O as indicator. RESULTS: After 5 h of ischemia, a significant reduction of all parameters studied was observed in skeletal muscle submitted to ischemia compared to the control limbs. CONCLUSIONS: Five-hour total ischemia applied to rat skeletal muscle led to the inhibition of the mitochondrial respiratory chain (represented by decreased state 3 and state 4 respiration rates). The percentage decrease in the electrical potential of the inner membrane was similar to the percentage reductions observed for state 4 respiration and the RCR. The parameter mostly affected by ischemia was ADP-activated respiration (state 3).