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Ready‐to‐eat (RTE) foods are widely marketed in China and are important components of everyday diet. In this study, a total of 2000 RTE food samples were analyzed, 252 (12.60%) of which were positive for Enterobacteriaceae, and 48 were identified as containing extended‐spectrum β‐lactamase (ESBL)‐producing Escherichia coli isolates. Furthermore, the antimicrobial resistance patterns of these isolates to 14 antimicrobial agents revealed that most isolates were resistant to aminoglycosides and β‐lactam antibiotics. The TEM‐type gene was prevalent in our isolates (79.17%). The isolates (n = 48) were classified into three clusters based on the ERIC‐PCR results. Forty‐eight sequence types were found without duplicates, revealing genetic variation and relatedness among isolates. Thus, the results demonstrated the presence of ESBL‐producing Enterobacteriaceae in Chinese RTE foods. The results of this study provide insights into the spread of antibiotic‐resistant strains and improve understanding of microbial risks. [ABSTRACT FROM AUTHOR]

With the increase in mining depth, the problem of the floor heave of a roadway is becoming increasingly prominent. Solving this problem for a deep high-stress roadway is the key to ensure safe supply and utilization of coal resources in China. This study investigates the floor heave of a horizontal transportation rock roadway at the depth of 960 m at the Xieyi Mine. A four-way loading simulation test frame similar to the Xieyi Mine was used to reproduce the high-stress environment of a deep roadway by loading different pressures on the roof, floor, and two sides of the roadway. The experimental results show that after the tunnel had been excavated, the surrounding rock failure could be divided into three stages: the initial deformation stage, fissure development stage, and mild deformation stage. The destruction time periods of these stages were 0–0.5 h, 0.5–2 h, and 2–6 h, and the destruction ranges were 0.4 m, 1 m, and 1.5 m, respectively. The amount of roof subsidence, the displacement of the two sides, and the floor heave influence each other, and the range of the bearing ring (5.6 m) of the floor is larger than that of the roof (3.4 m) after the surrounding rock has been damaged. The findings suggest that the floor should be supported first, before the two sides and the roof; then, the support of the key parts (roof and floor corners) should be strengthened. The roof, floor, and two sides are considered for controlling the deformation of the surrounding rock in a coupled trinity support mode. Because of the unfavorable conditions in the area, overexcavation backfill technology was used. The new support was successfully applied during the subsequent construction of the rock tunnel. Based on the long-term monitoring results of the surrounding rock deformation, the floor heave control yielded satisfactory results and maintained the long-term stability of the roadway. Therefore, this study can serve as a reference for preventing floor heave in similar high-stress roadways in the future. [ABSTRACT FROM AUTHOR]

Vibrio parahaemolyticus is a marine and estuarine bacterium that poses a major threat to human health worldwide. In this study, from 2017 to 2019, we evaluated 900 food samples collected from China in 2017, with the aim of determining the incidence and features of V. parahaemolyticus in ready-to-eat (RTE) foods, shrimp and fish in China. The contamination rates in these were 3.67, 19.33 and 10.67%, respectively, and the prevalence of V. parahaemolyticus was higher in summer than in winter. In addition, 101  V. parahaemolyticus strains were isolated. Our results suggested that most of the isolates were resistant to aminoglycosides based on the antimicrobial resistance patterns of these aquatic product isolates against 14 antimicrobial agents. Furthermore, most of the isolates were multidrug-resistant. Serotyping showed that the isolates of the O2 serotype comprised the maximum proportion. Enterobacterial repetitive intergenic consensus sequence (ERIC)-PCR results indicated that the isolates (n  = 101) could be classified into 12 clusters. There were 82 STs suggesting genetic variation and relatedness among these isolates. Our findings demonstrated the presence of V. parahaemolyticus in foods from Chinese retail markets and show that this methodology can be used for microbiological risk assessment in China. [ABSTRACT FROM AUTHOR]

Vibrio parahaemolyticus is a marine and estuarine bacterium that leads to damage of aquatic industry by foodborne outbreaks and possesses an enormous threat to food safety as well as human health worldwide. In the current study, we investigated 905 food samples (ready-to-eat foods, fish, and shrimp) from 15 provinces in China, and aimed to determine prevalence, biological characteristics and genetic diversity of presumptive V. parahaemolyticus isolates. Firstly, 14.17% of 240 fish samples, 15.34% of 365 shrimp samples and 3.67% of 300 RTE food samples were positive for potential V. parahaemolyticus. Secondly, 69 food samples (14.87%) collected in summer were positive for target isolates, while the rate of positive sample of 441 food samples in winter reached 7.26%. Thirdly, we purified 202 V. parahaemolyticus strains for further research. And antimicrobial susceptibility results of strains tested revealed that the highest resistance rate was observed for ampicillin (79.20%). At the same time, 148 (73.27%) of all isolates were classified and defined as multi-drug resistant foodborne bacteria. The results of PCR assay showed that the isolates being positive for the tdh , trh or both genes, were up to 9.90%, 19.80% or 3.96%. Besides, multiplex PCR test showed that the isolates carrying O2 serogroup were the most prevalent. Furthermore, sequence types (STs) of 108 isolates were obtained via multi-locus sequence typing. Not only 82 STs were detected, but also 41 of which were updated in the MLST database. Thus, our findings significantly demonstrated the high contamination rates of V. parahaemolyticus in fish and shrimp and it may possess potential threat for consumer health. We also provided up-to-date dissemination of antibiotic-resistant V. parahaemolyticus which is important to ensure the high efficacy in the treatment of human and aquatic products infections. Lastly, with the identification of 82 STs including 41 novel STs, this study significantly revealed the high genetic diversity among V. parahaemolyticus. All of our research improved our understanding on microbiological risk assessment in ready-to-eat foods, fish, and shrimp. [ABSTRACT FROM AUTHOR]

Spring water is an important direct drinking water resource. Enterococcus faecalis is a significant opportunistic pathogen from environment that causes human neonatal sepsis and urinary tract infections. Our study investigated the prevalence, virulence genes, antimicrobial resistance, and molecular characterization of E. faecalis from spring water in Guangdong, China. A total of 285 spring water samples were collected from January 2017 to January 2018, in which 47 (16.49%) samples were contaminated by E. faecalis. Antimicrobial susceptibility result showed that many isolates were resistant to tetracycline (93.6%), gentamicin (29.8%), and ciprofloxacin (25.5%). The virulence gene test revealed the positive rate of gelE, asa1, ace, and cylA were 100, 82.3, 76.6, and 70.2%, respectively. Enterobacterial repetitive intergenic consensus‐polymerase chain reaction and multilocus sequence typing classified 47 isolates into 12 and 5 clusters, respectively, which revealed the genetic relatedness and diversity. This finding illustrated the presence of virulence genes and provided understanding on the spread of antibiotic‐resistant and genetic diversity isolates. It can help us gradually increase our knowledge of microbiological risk management in E. faecalis from spring water. Practical applications: Investigating the prevalence of Enterococcus faecalis isolates from spring water could increase this microbial safety ondrinking water. In our research, antibiotic susceptibility, virulence genes, serotypingand molecular characteristic were selected to thorough comparison among Enterococcus faecalis isolates. Spring water is common in China as drinking water, then understanding the dissemination and monitoring the prevalence of this microorganism is necessary to improve the drinking water safety. [ABSTRACT FROM AUTHOR]

Terbium doped gadolinium oxysulfide (GOS:Tb) ceramics were successfully fabricated by pre-sintering in vacuum and HIP post-treatment in Ar atmosphere. Ceramic densification in vacuum and HIP was discussed in the detail mainly by relative density and FESEM characterizations. The fabricated GOS:Tb ceramics were translucent with 0.5 mm thickness after HIP post-treatment. Optical and scintillation properties of GOS:Tb ceramics were also investigated. Temperature-dependent X-ray excited spectra were recorded using a homemade XEL spectrometer. Neutron scintillation light output was also measured in China Spallation Neutron Source (CSNS). The light output was measured to be about 284 photons per neutron with different thicknesses of GOS:Tb ceramics. • Highly dense GOS:Tb ceramics were prepared by vacuum sintering combined with HIP post-treatment. • The light output of GOS:Tb ceramic scintillator screen is increased by 23% compared with powder form. • The fabricated GOS:Tb ceramic is very promising for using as scintillator in neutron imaging technology. [ABSTRACT FROM AUTHOR]

Consumption of contaminated salmon in China has led to pathogenic Vibrio parahaemolyticus infections in humans. In this study, 420 salmon samples were collected from supermarkets and restaurants in China that showed a contamination rate of 9.05 and 15.24%, respectively. Eighteen antibiotics were used to test the antibiotic susceptibility of all 51 isolates. The most common resistance was observed to β-lactam antibiotics and aminoglycosides, including ampicillin (92.16%), streptomycin (88.24%), kanamycin (45.10%) and cephazolin (45.10%). Meanwhile, many strains were resistant to more than two antibiotics (48/51, 94.12%). Only two and five isolates were positive for tdh and trh, respectively. Serotyping results demonstrated that O2 was most prevalence serotype (15/51, 29.41%). Molecular typing (enterobacterial repetitive intergenic consensus sequence polymerase chain reaction and multilocus sequence typing) allowed classification of all the isolates into 5 clusters and 44 sequence types, highlighting genetic variation and relatedness. In general, the high antibiotic resistance is alarming and raises public health concerns. Frequent monitoring of salmon for V. parahaemolyticus contamination, genetic diversity and antibiotic susceptibility is essential to improve seafood safety., (© FEMS 2019.)

Background: Vibrio parahaemolyticus is a major foodborne pathogen, particularly in Asian countries. Increased occurrence of outbreaks of V. parahaemolyticus gastroenteritis in China indicates the need to evaluation of the prevalence of this pathogenic species. V. parahaemolyticus distribution in shellfish from the eastern coast of China has been reported previously. However, to date, the prevalence of V. parahaemolyticus in retail aquatic products in North China has not been determined. To investigate the prevalence of V. parahaemolyticus in aquatic products in North China, 260 aquatic product samples were obtained from retail markets in 6 provinces of North China from November to December in 2012 and July to August in 2013., Results: V. parahaemolyticus was detected in 94 (36.2%) of the samples by the most probable number method. The density of V. parahaemolyticus ranged from 1.50 to 1100 MPN/g. V. parahaemolyticus was detected at a rate of 50.0% and 22.7% in summer and in winter, respectively. The density of V. parahaemolyticus was significantly higher in summer than in winter, with mean levels of 16.5 MPN/g and 5.0 MPN/g, respectively. Among 145 V. parahaemolyticus isolates examined, none of the isolates possessed tdh and trh. In multiplex PCR-based O-antigen serotyping of these 145 isolates, all serotypes, other than O6, O7, and O9, were detected, and serotype O2 was found to be the most prevalent (detected in 54 isolates). The 145 isolates were grouped into 7 clusters by enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) at a similarity coefficient of 0.66. The antimicrobial resistance patterns of these 145 isolates to 12 antimicrobial agents revealed that most of the isolates were resistant to streptomycin (86.2%), while fewer were resistant to ampicillin (49.6%), cefazolin (43.5%), cephalothin (35.9%), and kanamycin (22.1%). All of the examined isolates were susceptible to azithromycin and chloramphenicol., Conclusions: The findings of this study will help in defining appropriate monitoring programs, understanding of the dissemination of antibiotic resistant strains, and providing information for the assessment of exposure to this microorganism at the consumption level.

Vibrio parahaemolyticus is a common foodborne pathogen in aquatic products. To investigate the prevalence of Vibrio parahaemolyticus in aquatic products in South China, 224 samples were collected from markets in four provinces (11 cities) from May 2013 to January 2014. One hundred and fifty isolates were isolated from 98 samples. All isolates were analyzed for the presence of thermostable direct haemolysin (TDH) and TDH-related haemolysin (TRH) by PCR, antibiotic susceptibility analysis by disk diffusion method, serotyping by multiplex PCR and molecular typing by enterobacterial repetitive intergenic consensus sequence PCR (ERIC-PCR) typing. Although all 150 isolates were negative for tdh, 61 strains were trh positive (40.67%). Antimicrobial susceptibility results indicated that most strains were resistant to streptomycin (88.67%), cefazolin (66.00%) and ampicillin (62.67%). All strains were susceptible to chloramphenicol. Forty percent of all isolates were O2 type. The 150 isolates were grouped into three clusters by ERIC-PCR typing. The results demonstrated the presence of V. parahaemolyticus in aquatic products from the retail market and this methodology can be used for microbiological risk assessment in China., (© FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)