1.Colonization, drug resistance, and molecular epidemiological characteristics of methicillin-resistant Staphylococcus aureus among dairy farm workers in Xinjiang
Jiguo JIN ; Zhaojie WANG ; Yanggui CHEN ; Xixiao MA ; Wanting XU ; Xingyu WANG ; Xiangnan WEI ; Fan WU ; Xintao DANG ; Xueying XIANG ; Jianyong WU ; Fuye LI
Journal of Environmental and Occupational Medicine 2026;43(2):201-207
Background Methicillin-resistant Staphylococcus aureus (MRSA) is an important pathogen for both human bloodstream infections and mastitis in cows. However, little attention has been paid to the cross-host transmission of MRSA from cows to high-risk groups in China. Objective To determine the MRSA colonization rates among dairy cows and dairy farm workers in Xinjiang, identify the antibiotic resistance profiles and molecular characteristics of the isolates, and provide scientific evidence for the formulation of targeted infection control strategies. Method A cross-sectional survey combined with laboratory pathogen analysis was conducted. From June to August 2024, large-scale dairy farms in Xinjiang region were selected as study sites. Nasal swabs (n=96) and skin swabs (n=39) were collected from workers, and bovine nasal swab samples (n=109) were collected simultaneously. All samples were subjected to MRSA isolation, cultivation, and identification, followed by antibiotic susceptibility testing to characterize resistance phenotypes. Staphylococcus aureus protein A (Spa) typing was performed to determine strain genotypes and elucidate MRSA colonization rates and molecular epidemiological patterns. Results A total of 35 MRSA strains was successfully isolated from 244 samples. The MRSA colonization rates among dairy farm workers and dairy cows were 20.83% (20/96) and 12.84% (14/109), respectively, with an overall isolation rate of 14.34% (35/244). Among the workers, the nasal colonization rate was 16.67% (16/96), and the skin colonization rate was 12.82% (5/39). One worker exhibited MRSA colonization at multiple body sites. All MRSA strains were resistant to cefoxitin (100%, 35/35). The resistance rates to erythromycin and clindamycin were 42.86% (15/35) and 34.29% (12/35), respectively. Thirteen strains showed a multidrug-resistant phenotype, whereas all strains were susceptible to vancomycin. The MRSA isolates exhibited high genetic diversity, with 13 Spa types identified, among which t441 was the most prevalent (8 strains). Both t441 and t034 types were detected in samples from both the dairy cows and their handlers. These two Spa types also carried and stably inherited specific resistance combinations, including erythromycin–clindamycin–cefoxitin and ciprofloxacin–erythromycin–clindamycin–gentamicin–cefoxitin–tetracycline, and a statistically significant association was also observed between the two resistance profiles and the bacterial types (P < 0.001). In addition, one novel Spa type strain was identified. Conclusion MRSA colonization rates among dairy cows and dairy farm workers in Xinjiang are relatively high, with evidence of multi-site colonization. The isolates exhibit high levels of multidrug resistance and genetic diversity, indicating a potential risk of cross-host transmission.
2.Genotypic diversity and antibiotic resistance of Enterococcus in dairy farming workplaces
Xiangnan WEI ; Yanggui CHEN ; Jia HUANG ; Fulong WANG ; Jiguo JIN ; Fan WU ; Xixiao MA ; Zhaojie WANG ; Xingyu WANG ; Wanting XU ; Jianyong WU ; Fuye LI
Journal of Environmental and Occupational Medicine 2026;43(5):582-590
Background Under intensive dairy farming conditions, Enterococcus spp. can be transmitted between animals, farm workers, and the environment via multiple vectors such as feces, soil, water, air, and farming equipment, posing a potential threat to public health. Objective To elucidate the prevalence, distribution, and antimicrobial resistance profiles of Enterococcus faecalis (E. faecalis) and Enterococcus faecium (E. faecium) among farm workers, dairy cattle, and the farm environment in Xinjiang, and to assess the risk of their cross-host transmission. Methods From May 2024 to January 2025, a total of 317 samples were collected from 11 large-scale dairy farms in Xinjiang, China, including feces from farm workers (n=130) and dairy cattle (n=154), and environmental samples (n=33). E. faecalis and E. faecium were isolated and identified, followed by antimicrobial susceptibility testing and multilocus sequence typing (MLST) to analyze their molecular characteristics. Results A total of 183 Enterococcus isolates were obtained (66 E. faecalis and 117 E. faecium isolated). The isolation rates of both species showed statistically significant differences among the three sources (χ2=29.21, P=0.003). Antimicrobial resistance analysis revealed that E. faecalis generally exhibited higher resistance rates across multiple antibiotic classes than E. faecium. High resistance to rifampicin was observed across all sources (50.00%–81.25%), with statistical variation among origins (χ2=8.03, P=0.024). Multidrug-resistant strains accounted for 69.10% of the isolates. Multidrug resistance patterns in E. faecium varied significantly by source (χ2=27.19, P=0.014), and one isolate displayed resistance to eight antibiotic classes. MLST indicated high genetic diversity; E. faecalis was dominated by ST472 and ST227 of which the distrubution was significantly different among sources, while E. faecium primarily clustered into clonal complexes CC94 (centered on ST94) and CC17 (centered on ST22). Conclusion Resistant Enterococcus strains exhibit cross-transmission among farm workers, animals, and the environment. Under the "One Health" framework, standardized farming protocols and prudent antimicrobial use are essential to disrupt the transmission chain of resistant clones and mitigate the spread of antimicrobial resistance at its source.
3.Genotypic diversity and antibiotic resistance of Enterococcus in dairy farming workplaces
Xiangnan WEI ; Yanggui CHEN ; Jia HUANG ; Fulong WANG ; Jiguo JIN ; Fan WU ; Xixiao MA ; Zhaojie WANG ; Xingyu WANG ; Wanting XU ; Jianyong WU ; Fuye LI
Journal of Environmental and Occupational Medicine 2026;43(5):582-590
Background Under intensive dairy farming conditions, Enterococcus spp. can be transmitted between animals, farm workers, and the environment via multiple vectors such as feces, soil, water, air, and farming equipment, posing a potential threat to public health. Objective To elucidate the prevalence, distribution, and antimicrobial resistance profiles of Enterococcus faecalis (E. faecalis) and Enterococcus faecium (E. faecium) among farm workers, dairy cattle, and the farm environment in Xinjiang, and to assess the risk of their cross-host transmission. Methods From May 2024 to January 2025, a total of 317 samples were collected from 11 large-scale dairy farms in Xinjiang, China, including feces from farm workers (n=130) and dairy cattle (n=154), and environmental samples (n=33). E. faecalis and E. faecium were isolated and identified, followed by antimicrobial susceptibility testing and multilocus sequence typing (MLST) to analyze their molecular characteristics. Results A total of 183 Enterococcus isolates were obtained (66 E. faecalis and 117 E. faecium isolated). The isolation rates of both species showed statistically significant differences among the three sources (χ2=29.21, P=0.003). Antimicrobial resistance analysis revealed that E. faecalis generally exhibited higher resistance rates across multiple antibiotic classes than E. faecium. High resistance to rifampicin was observed across all sources (50.00%–81.25%), with statistical variation among origins (χ2=8.03, P=0.024). Multidrug-resistant strains accounted for 69.10% of the isolates. Multidrug resistance patterns in E. faecium varied significantly by source (χ2=27.19, P=0.014), and one isolate displayed resistance to eight antibiotic classes. MLST indicated high genetic diversity; E. faecalis was dominated by ST472 and ST227 of which the distrubution was significantly different among sources, while E. faecium primarily clustered into clonal complexes CC94 (centered on ST94) and CC17 (centered on ST22). Conclusion Resistant Enterococcus strains exhibit cross-transmission among farm workers, animals, and the environment. Under the "One Health" framework, standardized farming protocols and prudent antimicrobial use are essential to disrupt the transmission chain of resistant clones and mitigate the spread of antimicrobial resistance at its source.
4.Personal protection and influencing factors of livestock workers in Xinjiang
Xixiao MA ; Xueying XIANG ; Zhaojie WANG ; Wanting XU ; Jiguo JIN ; Fan WU ; Xiangnan WEI ; Jianyong WU ; Fuye LI
Journal of Environmental and Occupational Medicine 2025;42(5):578-585
Background Personal protection is crucial for reducing the risk of zoonotic pathogen infection among livestock workers. Investigating the current status of its implementation and associated influencing factors can provide empirical evidence for developing more effective intervention measures. Objective To investigate the current status of personal protection implementation among livestock workers in Xinjiang, China and its influencing factors, providing a reference for formulating targeted intervention measures. Methods This study was conducted in Bayingolin Mongol Autonomous Prefecture, Kashgar region, and the First and Eighth Divisions of Xinjiang Production and Construction Corps. We selected large-scale cattle and sheep farms, cooperatives, individual livestock households, livestock trading markets, slaughterhouses, and retail markets. Using cluster sampling, we recruited all livestock workers (
5.Construction and identification of a sizeable naive human Fab phage display antibody library
Yakun ZHAO ; Xiaoyue WEI ; Fanliang MENG ; Wentao LIU ; Jiaming FAN ; Lijin LONG ; Wanting WANG ; Jianling CHEN ; Jianzhong ZHANG ; Lihua HE ; Liyong LIU ; Rui ZHAO ; Di SUN ; Xuezhen YUAN ; Xiaomei YAN
Chinese Journal of Epidemiology 2025;46(2):288-295
Objective:To construct a sizeable naive human Fab phage display antibody library to screen high-affinity specific antibodies in vitro. Methods:Total RNA was extracted from peripheral blood mononuclear cells (PBMCs) of 126 healthy individuals, subsequently reverse-transcribed into cDNA, and used as a template. PCR amplification was performed to obtain the V H from IgG, IgM and light chain κ, λ, separately, with the initial PCR products serving as templates for a second round of PCR. Overlap extension PCR was employed to generate fragments of the κ and λ light chains. These fragments were ligated with the phage vector pNC3, which harbors the variable region 1 of the heavy chain, to construct a recombinant phage plasmid. This plasmid was then electroporated into competent Escherichia Coli TG1 cells to establish a naive human Fab phage display antibody library. One hundred clones were randomly selected for identification and sequencing, and antibody gene polymorphisms were analyzed using the IMGT database and MAFFT software. Recombinant α-hemolysin from Staphylococcus aureus was utilized to screen Fab antibody fragments through biopanning of the antibody library, followed by random selection of phage ELISA-identified clones. The positive clones (antigen A450∶blank control A450≥2.1) were sequenced. Results:Two large naive Fab phage display antibody libraries were successfully constructed, in which the capacity of κ and λ chain antibody libraries were 1.25×10 11 and 1.54×10 11, respectively. The titers for two antibody libraries were 6.04×10 13 CFU/ml and 3.50×10 13 CFU/ml. The positive transformation insertion rates for κ and λ chain antibody libraries were 96% (96/100) and 100% (100/100), respectively. Sequence analysis revealed that all antibody sequences were unique. The amino acid sequences in the skeletal region were relatively conserved. In contrast, significant variations in the length of the complementarity determining region (CDR) were found, and the diversity of amino acid sequence of the complementary determining region was high, especially the CDR3. Analysis using the IMGT database indicated that the sequences exhibited a broad distribution across variable-diversity-joining gene families. After six rounds of panning, specific phage antibodies enrichment targeting α-hemolysin were achieved. A total of 142 monoclonal antibodies were sequenced, yielding 8 distinct Fab antibody sequences. Conclusion:This study successfully constructed two naive human Fab phage display antibody libraries with large capacity and good diversity, which can be used for screening human antibodies for serum epidemiology.
6.Impact of dairy farming on gut microbiota structure and diversity of practitioners
Zhaojie WANG ; Xixiao MA ; Xianxia LIU ; Yanggui CHEN ; Xueying XIANG ; Wanting XU ; Jiguo JIN ; Fan WU ; Xiangnan WEI ; Jianyong WU ; Fuye LI
Journal of Environmental and Occupational Medicine 2025;42(6):668-673
Background Animal farming may affect the structure and diversity of gut microbiota of farm workers, but it needs more studies to provide solid evidence. Objective To analyze the diversity characteristics of gut microbiota in dairy farm workers, dairy cows, and the control population (non-animal contact occupational group), and to assess the impact of dairy farming on the gut microbiota of workers. Methods The 16S rRNA full-length amplicon sequencing technology was used to sequence 60 fecal samples from dairy farm workers, 89 from dairy cows, and 50 from the general population. The gut microbiota structure characteristics, including operational taxonomic units (OTUs), alpha diversity, beta diversity, and the composition of species at the phylum, family, and genus levels were analyzed. The differences in gut microbiota among the three groups of samples were compared to explore the impact of occupational exposure on the gut microbiota structure of dairy farm workers. Results A total of
7.Construction and identification of a sizeable naive human Fab phage display antibody library
Yakun ZHAO ; Xiaoyue WEI ; Fanliang MENG ; Wentao LIU ; Jiaming FAN ; Lijin LONG ; Wanting WANG ; Jianling CHEN ; Jianzhong ZHANG ; Lihua HE ; Liyong LIU ; Rui ZHAO ; Di SUN ; Xuezhen YUAN ; Xiaomei YAN
Chinese Journal of Epidemiology 2025;46(2):288-295
Objective:To construct a sizeable naive human Fab phage display antibody library to screen high-affinity specific antibodies in vitro. Methods:Total RNA was extracted from peripheral blood mononuclear cells (PBMCs) of 126 healthy individuals, subsequently reverse-transcribed into cDNA, and used as a template. PCR amplification was performed to obtain the V H from IgG, IgM and light chain κ, λ, separately, with the initial PCR products serving as templates for a second round of PCR. Overlap extension PCR was employed to generate fragments of the κ and λ light chains. These fragments were ligated with the phage vector pNC3, which harbors the variable region 1 of the heavy chain, to construct a recombinant phage plasmid. This plasmid was then electroporated into competent Escherichia Coli TG1 cells to establish a naive human Fab phage display antibody library. One hundred clones were randomly selected for identification and sequencing, and antibody gene polymorphisms were analyzed using the IMGT database and MAFFT software. Recombinant α-hemolysin from Staphylococcus aureus was utilized to screen Fab antibody fragments through biopanning of the antibody library, followed by random selection of phage ELISA-identified clones. The positive clones (antigen A450∶blank control A450≥2.1) were sequenced. Results:Two large naive Fab phage display antibody libraries were successfully constructed, in which the capacity of κ and λ chain antibody libraries were 1.25×10 11 and 1.54×10 11, respectively. The titers for two antibody libraries were 6.04×10 13 CFU/ml and 3.50×10 13 CFU/ml. The positive transformation insertion rates for κ and λ chain antibody libraries were 96% (96/100) and 100% (100/100), respectively. Sequence analysis revealed that all antibody sequences were unique. The amino acid sequences in the skeletal region were relatively conserved. In contrast, significant variations in the length of the complementarity determining region (CDR) were found, and the diversity of amino acid sequence of the complementary determining region was high, especially the CDR3. Analysis using the IMGT database indicated that the sequences exhibited a broad distribution across variable-diversity-joining gene families. After six rounds of panning, specific phage antibodies enrichment targeting α-hemolysin were achieved. A total of 142 monoclonal antibodies were sequenced, yielding 8 distinct Fab antibody sequences. Conclusion:This study successfully constructed two naive human Fab phage display antibody libraries with large capacity and good diversity, which can be used for screening human antibodies for serum epidemiology.
8.The effective components of Chinese medicine combined with scaffold materials promote bone tissue regeneration
Xinyu DONG ; Xinyue DONG ; Wanting WANG ; Haixia FAN ; Huanzhi CHENG
Chinese Journal of Tissue Engineering Research 2024;28(20):3240-3245
BACKGROUND:With the proven ability of traditional Chinese medicine such as icariin and berberine to promote bone regeneration by regulating various mechanisms and targets,researchers have combined active ingredients of traditional Chinese medicine with bone tissue engineering and found that they have unique advantages in treating bone defects. OBJECTIVE:Starting from the active ingredients of traditional Chinese medicines that promote bone formation,to screen cases of their effective combination with different drug-carrying scaffold materials,and summarize the active ingredients of traditional Chinese medicines that have the potential to be applied to bone tissue engineering. METHODS:CNKI,WanFang,PubMed,and Web of Science were searched for relevant literature published from 2000 to 2023,using the keywords of"bone tissue engineering,bone tissue-engineered scaffold materials,bone defect,bone repair,bone regeneration,traditional Chinese medicine"in Chinese and English.According to the inclusion and exclusion criteria,87 papers were finally included for review. RESULTS AND CONCLUSION:There are various kinds of active ingredients of traditional Chinese medicine to promote bone regeneration,mainly including flavonoids,non-flavonoid polyphenols,alkaloids,glycosides.These active ingredients have anti-inflammatory and analgesic effects,promote osteoblasts,inhibit osteoclasts and promote early angiogenesis.The combination of active ingredients of traditional Chinese medicine with bone tissue engineering is effective in anti-inflammation,accelerating collagen and bone formation,and promoting the expression of osteogenic genes,which provides a theoretical basis for the application of traditional Chinese medicine in bone tissue regeneration,and at the same time provides a new idea for the repair of bone defects.
9.Investigation and analysis of the status quo of knowledge and attitude of cardiopulmonary resuscitation among 714 community residents in Shanghai
Li FENG ; Xiaohua XU ; Piaoyu YANG ; Ji CAI ; Jiayu ZHUANG ; Wanting ZHOU ; Fan XU ; Yuxia ZHANG
Chinese Journal of Modern Nursing 2020;26(14):1850-1856
Objective:To explore the knowledge and attitude of cardiopulmonary resuscitation (CPR) in community residents in Shanghai and analyze the influencing factors.Methods:The residents in 16 communities in Shanghai were selected by convenient sampling and investigated from November 2018 to June 2019, and a total of 714 valid questionnaires were recovered. The residents' CPR knowledge and attitude were analyzed descriptively, and multiple linear regression was used to analyze the influencing factors.Results:The total score of CPR knowledge among the 714 community residents in Shanghai was (24.58±7.80) , with a passing rate of 36.13% (258/714) , and the passing rate of "artificial respiration knowledge" was the lowest, which was 38.66% (276/714) . The total score of the residents' CPR attitude was (40.95±5.18) , and the average scores of "attitude to learning CPR" and "attitude to implementing CPR" were (3.60±0.45) and (3.22±0.50) , respectively. Analysis of the influencing factors showed that gender, age, education level, conscious health status, whether they have heard of CPR, whether they have received CPR training, and whether they have encountered emergency rescue communities were the influencing factors to the community residents' CPR knowledge and attitude ( P < 0.05) . Conclusions:The overall CPR knowledge level of the community residents in Shanghai is relatively low, and the residents prefer to learn CPR and implement CPR for their relatives and friends, rather than strangers. Younger, better conscious health status, and having heard of CPR can help the residents improve their CPR knowledge and attitude, while women, higher education level, and residents who have encountered emergency rescue communities have better CPR knowledge. The CPR training has a positive effect on the residents' attitude to learning and implementing CPR. Future CPR training needs to increase the training intensity and duration, and help the residents to improve the level of CPR knowledge and attitude.
10.Effects of Simulated Microgravity on Function of SOC Channels in Osteocytes MLO-Y4
Wanting DU ; Xiao YANG ; Yubo FAN ; Lianwen SUN
Journal of Medical Biomechanics 2019;34(3):E277-E282
Objective To study the effect of simulated microgravity on activity of the store-operated calcium (SOC) channels in osteocytes and its possible mechanism, so as to elucidate the potential mechanism of weightlessness bone loss. Methods Osteocytes (MLO-Y4) as the experimental subjects were divided into simulated microgravity (SM) group and normal gravity group (CON). After rotating for 24 h and 48 h, confocal microscope was used to detect the intracellular calcium ion concentration level to reflect activity of the SOC channels after thapsigargin (TG)-induced endoplasmic reticulum (ER) depletion. Immunofluorescence staining was used to observe the distribution of ER membrane protein IP3R and spectrin membrane skeleton, in order to preliminarily explore the possible mechanism of functional changes of SOC channels. Results During the period of calcium release from ER, [Ca2+]i had no significant difference between SM group and CON group for 24 h and 48 h; while during the period of extracellular calcium influx by SOC channels, [Ca2+]i of SM group had significant differences in the first 4 minutes for 24 h, as well as in the whole time for 48 h. Compared with CON group, the spectrin membrane skeleton of SM group was gathered at the rim of membrane, while ER membrane protein IP3R of SM group was gathered at the nuclear envelope of ER. These two tendencies were more obvious for 48 h. Conclusions The stimulated microgravity could inhibit activity of SOC channels in osteocytes. Changes in the distribution of the spectrin membrane skeleton and ER membrane protein IP3R under the simulated microgravity might reduce the activity of SOC channels by affecting the conformation coupling process between the membrane and ER.

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