Investigation of Extended-Spectrum and AmpC ß-Lactamase-Producing Enterobacteriaceae from Retail Seafood in Berlin, Germany.

Retail seafood in Berlin, Germany, was investigated to detect the prevalence and quantitative load of Enterobacteriaceae that produce extended-spectrum ß-lactamase (ESBL) and AmpC ß-lactamase (AmpC). A total of 160 raw seafood samples were screened for the presence of these bacteria using MacConkey agar supplemented with 1 mg/L cefotaxime after nonselective enrichment. Isolated species were subsequently identified using matrix-assisted laser desorption-ionization time-of-flight analysis. ESBL and AmpC production was tested by the disk diffusion method, and ESBL and AmpC genes were characterized using real-time and conventional PCR assays with DNA sequencing. Spread plating was used for quantification of ESBL- and AmpC-producing Enterobacteriaceae. Overall, these bacteria were detected in 21.3% of seafood samples (34 of 160 samples) with prevalences of 22.5 and 20% for shrimp and bivalves, respectively. Of the positive samples, 91.2% contained an ESBL- or AmpC-producing Enterobacteriaceae load of <100 CFU/g (lower detection limit), and 8.8% contained 100 to 1,000 CFU/g. Among the 45 Enterobacteriaceae isolates, Klebsiella pneumoniae (13 isolates) and Escherichia coli (12 isolates) were the predominant species. ESBL and AmpC genes were detected in 33 isolates, with the majority of isolates harboring blaCTX-M (27.3%), blaCMY (21.2%), or blaDHA (21.2%). Our study highlights the hazard associated with seafood containing ESBL- and AmpC-producing Enterobacteriaceae in Germany. Even though the contamination levels were low, the high prevalence of ESBL- and AmpC-producing Enterobacteriaceae in seafood might be of concern to public health because of the potential transmission of these bacteria from seafood to humans through the food chain.

In Vivo Degradation Performance of High-Purity Magnesium Subjected to Quantitative Mechanical Load / 医用生物力学

Objective To study the effects of mechanical load on in vivo degradation performance of high-purity magnesium (HP Mg, 99.99 wt.%) quantitatively. Methods Cylindrical Mg specimens, with a 2 mm diameter and a 14 mm length, were mounted in polyetheretherketone (PEEK) rings to bear compressive stresses ［（6.2±0.6） MPa］, tensile stresses ［（4.6±0.1） MPa］ or no stress (as control). The specimens under different stress states were implanted subcutaneously in dorsal abdominal regions of SD rats for 4 weeks. The mass loss, residual volume and surface morphology of the specimens and staining of surrounding soft tissues were used to analyze the degradation rate of HP Mg. Results Specimens and rings were completely encapsulated by membranous tissues after implantation for 4 weeks. No significant differences in the degradation rates were noted between specimens bearing stress and the control. The corrosion layers of specimens under each stress state were uniform. Conclusions The compressive and tensile stresses (4-6 MPa) could not affect significantly HP Mg degradation performance in vivo. The research findings provide theoretical references for the design and clinical application of Mg-based degradable implants.

Multidirectional lip-closing force in adult females after short-term lip training.

The purpose of this study was to investigate the multidirectional lip-closing force in adult females before and after short-term lip training. Sixty-six Japanese females participated in this study. The subjects performed lip training that involved maintaining 200 or 400 g of bottled water in the oral vestibule. The signals of directional lip-closing force were investigated in eight directions before training and 5 and 7 days after the lip training. The differences in the closing force between pre- and post-training were then analysed statistically. The lip-closing force increased in the following order: pre-training, 5 days post-training and 7 days post-training in every direction (P < 0·05). The patterns of the increase in the lip-closing force in the upper, lower, right and left directions as a result of the repetitions were similar. No significant differences were noted between the training effects with loads of 200 and 400 g. Our findings demonstrated that the lip-closing force was influenced by the short-term lip training.

Distribution, quantitative load and characterization of Salmonella associated with swine farms in upper-northern Thailand.

This study was conducted to analyze the prevalence and quantitative loads of Salmonella spp. on pig farms in Chiang Mai, Lamphun, Thailand to assess loading levels before slaughtering. The serotype diversity, antimicrobial-resistance pattern and pulse-field type of Salmonella spp. were also characterized to assess the dynamic propagation of the pathogen. The Salmonella-positive prevalence was 246/805 (30.56%), and the quantitative loads varied from 1.48 ˜ 4.04 Log10MPN/g, with a mean ± standard deviation of 2.11 ± 0.57. AMP/S/TE (ampicillin/streptomycin/tetracycline) was the highest frequency antimicrobial resistance pattern found in this study. In addition, Salmonella Rissen was the primary serotype in this region. PFGE results indicated the occurrence of infection by cross contamination among pig farms. Our study showed that pork is easily contaminated with this pathogen. Farm control programs must be based on strict biosecurity and hygienic measures, which could further reduce the contamination pressure at slaughterhouses or retail shops.

Distribution, quantitative load and characterization of Salmonella associated with swine farms in upper-northern Thailand

This study was conducted to analyze the prevalence and quantitative loads of Salmonella spp. on pig farms in Chiang Mai, Lamphun, Thailand to assess loading levels before slaughtering. The serotype diversity, antimicrobial-resistance pattern and pulse-field type of Salmonella spp. were also characterized to assess the dynamic propagation of the pathogen. The Salmonella-positive prevalence was 246/805 (30.56%), and the quantitative loads varied from 1.48~4.04 Log10MPN/g, with a mean +/- standard deviation of 2.11 +/- 0.57. AMP/S/TE (ampicillin/streptomycin/tetracycline) was the highest frequency antimicrobial resistance pattern found in this study. In addition, Salmonella Rissen was the primary serotype in this region. PFGE results indicated the occurrence of infection by cross contamination among pig farms. Our study showed that pork is easily contaminated with this pathogen. Farm control programs must be based on strict biosecurity and hygienic measures, which could further reduce the contamination pressure at slaughterhouses or retail shops.