In this study, the milk samples of 1 021 cows in eight dairy farms in Eastern Hebei Province were collected and detected with LMT reagent and somatic cell count for subclinical mastitis. Pathogenic bacteria in subclin...In this study, the milk samples of 1 021 cows in eight dairy farms in Eastern Hebei Province were collected and detected with LMT reagent and somatic cell count for subclinical mastitis. Pathogenic bacteria in subclinical mastitis positive milk samples were isolated and identified.The results showed that 60.63%（619/1 021） of the sampled cows were diagnosed with subclinical mastitis, and mixed infections accounted for 88.21%（546/619） of the cases. In addition, 82 strains of 14 species were isolated from the subclinical mastitis positive milk samples, including 36 strains of Staphylococcus（43.90%）, 33 strains of Streptococcus（40.24%）, 8 strains of Enterobacteriaceae（9.76%） and 5 strains of Corynebacterium（6.10%）, respectively. The results proved that Staphylococcus aureus and Streptococcus agalactiae are the main pathogenic bacteria causing bovine subclinical mastitis in Eastern Hebei Province.展开更多
In order to explore moldy mechanism of chestnut from Luotian County in storage process,the strains of pathogenic fungi were isolated from chestnuts after storage at room temperature for 70d.Six genera of fungi were fo...In order to explore moldy mechanism of chestnut from Luotian County in storage process,the strains of pathogenic fungi were isolated from chestnuts after storage at room temperature for 70d.Six genera of fungi were found in chestnut through experimental identification,which were Ozoniumsp.,Fusarium sp.,Aspergillus sp.,Penicilliumsp.,Rhiopus sp.and Stachybotrys sp.,respectively.The re-inoculation tests had been conducted on pathogenic fungi whose isolating rate was greater than 10%.The result showed that the rest genera of fungi generally had no pathogenicity except Penicilliumsp.could infect non-injured chestnut with a lower moldy rate and lighter symptoms;but the moldy rate of strains was above 60% in injured inoculation and they showed heavy symptoms,among which the moldy rate of Ozoniumsp.and Aspergillus sp.were higher than 80%.The experimental results showed that injured chestnut were more likely to decay.Ozoniumsp.and Aspergillus sp.were important pathogenic fungi causing decay during storage process of chestnut.展开更多
This study was conducted in order to determine the fungi and bacteria associated with tomato plants at Cameron Highlands Malaysia. The fungi which have been isolated and detected from tomato plants were: Fusarium oxys...This study was conducted in order to determine the fungi and bacteria associated with tomato plants at Cameron Highlands Malaysia. The fungi which have been isolated and detected from tomato plants were: Fusarium oxysporum, F. solani, F. acuminatum, Rhizoctonia solani, Colletotrichum boninense, C. acutatum and Phoma destructiva. The bacteria which have been isolated and detected from tomato plants were: Ralstonia solanacearum, Xanthomonas vesicatoria, X. gardneri and Pseudomonas syringae. While the most pathogenic fungi were C. boninense, P. destructive and F. oxysporum with the disease incidence (89.6%, 86.6%, 85.6%) respectively, the most pathogenic bacteria were X. vesicatoria and R. solanacearum with the disease incidence (96.6% and 87.6%) respectively.展开更多
The highly pathogenic avian influenza （HPAI） H5N1 virus has caused several outbreaks in domestic poultry. Despite great efforts to control the spread of this virus, it continues to evolve and poses a substantial thr...The highly pathogenic avian influenza （HPAI） H5N1 virus has caused several outbreaks in domestic poultry. Despite great efforts to control the spread of this virus, it continues to evolve and poses a substantial threat to public health because of a high mortality rate. In this study, we sequenced whole genomes of eight H5N1 avian influenza viruses isolated from domestic poultry in eastern China and compared them with those of typical influenza virus strains. Phylogenetic analyses showed that all eight genomes belonged to clade 2.3.2.1 and clade 7.2, the two main circulating clades in China. Viruses that clustered in clade 2.3.2.1 shared a high degree of homology with H5N1 isolates located in eastern Asian. Isolates that clustered in clade 7.2 were found to circulate throughout China, with an east-to-west density gradient. Pathogenicity studies in mice showed that these isolates replicate in the lungs, and clade 2.3.2.1 viruses exhibit a notably higher degree of virulence compared to clade 7.2 viruses. Our results contribute to the elucidation of the biological characterization and pathogenicity of HPAI H5N1 viruses.展开更多
Introduction:The hypervirulent communityassociated methicillin-resistant Staphylococcus aureus(S.aureus,CA-MRSA)sequence type 8(ST8)clone has disseminated globally yet remains only sporadically documented in Chinese c...Introduction:The hypervirulent communityassociated methicillin-resistant Staphylococcus aureus(S.aureus,CA-MRSA)sequence type 8(ST8)clone has disseminated globally yet remains only sporadically documented in Chinese clinical settings.To date,staphylococcal food poisoning outbreaks attributable to ST8 strains have not been reported in China.Methods:Comprehensive epidemiological and laboratory investigations were conducted,encompassing the isolation of pathogenic microorganisms from food samples,environmental swabs,and patient anal swabs.Recovered isolates underwent antimicrobial susceptibility testing,enterotoxin detection,whole-genome sequencing,and phylogenetic and prophage characterization.Results:Five S.aureus isolates were successfully recovered from seven specimens.All isolates were identified as ST8(CC8)-spa t024,harbored enterotoxin genes(sea,seq,and sek),and demonstrated penicillin resistance.Rice balls contaminated with the pathogen were identified as the outbreak source.Phylogenetic analysis revealed that the outbreak ST8 strains clustered within a distinct evolutionary subclade(Clade II.1)and exhibited close genetic relatedness to European lineages.The sea,seq,and sek genes were localized on a prophage carrying a type D immune evasion cluster that also encoded the sak and scn genes.Conclusions:This represents the first documented ST8-spa t024 methicillin-susceptible S.aureus food poisoning outbreak in China,involving a toxigenic clone with characteristics associated with hypervirulent lineages,thereby highlighting an emerging public health threat.Enhanced surveillance of ST8 strains among food products and food handlers is urgently needed.展开更多
基金Supported by Beef Cattle Disease Prevention and Control Project of Agricultural Industry Technology System of Hebei ProvinceThe Fund of Qinhuangdao Science and Technology Bureau(200901A070)China Spark Program(2012GA620002)
文摘In this study, the milk samples of 1 021 cows in eight dairy farms in Eastern Hebei Province were collected and detected with LMT reagent and somatic cell count for subclinical mastitis. Pathogenic bacteria in subclinical mastitis positive milk samples were isolated and identified.The results showed that 60.63%（619/1 021） of the sampled cows were diagnosed with subclinical mastitis, and mixed infections accounted for 88.21%（546/619） of the cases. In addition, 82 strains of 14 species were isolated from the subclinical mastitis positive milk samples, including 36 strains of Staphylococcus（43.90%）, 33 strains of Streptococcus（40.24%）, 8 strains of Enterobacteriaceae（9.76%） and 5 strains of Corynebacterium（6.10%）, respectively. The results proved that Staphylococcus aureus and Streptococcus agalactiae are the main pathogenic bacteria causing bovine subclinical mastitis in Eastern Hebei Province.
基金Supported by Key Project of Natural Science Foundation of Hubei Province(2010CBB03901)Key Project of Production-study-research Cooperation Fund for University by Hubei Education Department(C2010060)Forestry Science Technique Extension and Demonstration Project of Central Budget in 2011(2011BH0032)
文摘In order to explore moldy mechanism of chestnut from Luotian County in storage process,the strains of pathogenic fungi were isolated from chestnuts after storage at room temperature for 70d.Six genera of fungi were found in chestnut through experimental identification,which were Ozoniumsp.,Fusarium sp.,Aspergillus sp.,Penicilliumsp.,Rhiopus sp.and Stachybotrys sp.,respectively.The re-inoculation tests had been conducted on pathogenic fungi whose isolating rate was greater than 10%.The result showed that the rest genera of fungi generally had no pathogenicity except Penicilliumsp.could infect non-injured chestnut with a lower moldy rate and lighter symptoms;but the moldy rate of strains was above 60% in injured inoculation and they showed heavy symptoms,among which the moldy rate of Ozoniumsp.and Aspergillus sp.were higher than 80%.The experimental results showed that injured chestnut were more likely to decay.Ozoniumsp.and Aspergillus sp.were important pathogenic fungi causing decay during storage process of chestnut.
文摘This study was conducted in order to determine the fungi and bacteria associated with tomato plants at Cameron Highlands Malaysia. The fungi which have been isolated and detected from tomato plants were: Fusarium oxysporum, F. solani, F. acuminatum, Rhizoctonia solani, Colletotrichum boninense, C. acutatum and Phoma destructiva. The bacteria which have been isolated and detected from tomato plants were: Ralstonia solanacearum, Xanthomonas vesicatoria, X. gardneri and Pseudomonas syringae. While the most pathogenic fungi were C. boninense, P. destructive and F. oxysporum with the disease incidence (89.6%, 86.6%, 85.6%) respectively, the most pathogenic bacteria were X. vesicatoria and R. solanacearum with the disease incidence (96.6% and 87.6%) respectively.
基金supported in part by the funding from the National Natural Scientific Foundation(81370518)the National High Technology Research and Development Program of China(2015AA020924 and 2013ZX10004003)supported by a grant from the Beijing Nova Program(No.Z141107001814054)
文摘The highly pathogenic avian influenza （HPAI） H5N1 virus has caused several outbreaks in domestic poultry. Despite great efforts to control the spread of this virus, it continues to evolve and poses a substantial threat to public health because of a high mortality rate. In this study, we sequenced whole genomes of eight H5N1 avian influenza viruses isolated from domestic poultry in eastern China and compared them with those of typical influenza virus strains. Phylogenetic analyses showed that all eight genomes belonged to clade 2.3.2.1 and clade 7.2, the two main circulating clades in China. Viruses that clustered in clade 2.3.2.1 shared a high degree of homology with H5N1 isolates located in eastern Asian. Isolates that clustered in clade 7.2 were found to circulate throughout China, with an east-to-west density gradient. Pathogenicity studies in mice showed that these isolates replicate in the lungs, and clade 2.3.2.1 viruses exhibit a notably higher degree of virulence compared to clade 7.2 viruses. Our results contribute to the elucidation of the biological characterization and pathogenicity of HPAI H5N1 viruses.
基金Supported by the Health Commission of Zhejiang Province Medical Science and Technology Program Project(No.2025HY1485)the Planned Science and Technology Project of Traditional Chinese Medicine of Zhejiang Province of China(No.2023ZL352)the Capital’s Funds for Health Improvement and Research(No.2024-2G-4363).
文摘Introduction:The hypervirulent communityassociated methicillin-resistant Staphylococcus aureus(S.aureus,CA-MRSA)sequence type 8(ST8)clone has disseminated globally yet remains only sporadically documented in Chinese clinical settings.To date,staphylococcal food poisoning outbreaks attributable to ST8 strains have not been reported in China.Methods:Comprehensive epidemiological and laboratory investigations were conducted,encompassing the isolation of pathogenic microorganisms from food samples,environmental swabs,and patient anal swabs.Recovered isolates underwent antimicrobial susceptibility testing,enterotoxin detection,whole-genome sequencing,and phylogenetic and prophage characterization.Results:Five S.aureus isolates were successfully recovered from seven specimens.All isolates were identified as ST8(CC8)-spa t024,harbored enterotoxin genes(sea,seq,and sek),and demonstrated penicillin resistance.Rice balls contaminated with the pathogen were identified as the outbreak source.Phylogenetic analysis revealed that the outbreak ST8 strains clustered within a distinct evolutionary subclade(Clade II.1)and exhibited close genetic relatedness to European lineages.The sea,seq,and sek genes were localized on a prophage carrying a type D immune evasion cluster that also encoded the sak and scn genes.Conclusions:This represents the first documented ST8-spa t024 methicillin-susceptible S.aureus food poisoning outbreak in China,involving a toxigenic clone with characteristics associated with hypervirulent lineages,thereby highlighting an emerging public health threat.Enhanced surveillance of ST8 strains among food products and food handlers is urgently needed.
