期刊：
COMPARATIVE IMMUNOLOGY MICROBIOLOGY AND INFECTIOUS DISEASES,2024年109:102179 ISSN：0147-9571
通讯作者：
Li, MX;Ma, Zhiyong;Liu, K
作者机构：
[Li, MX; Li, Manxiang; Xie, Fengyu] Hunan Agr Univ, Coll Vet Med, Changsha 410128, Hunan Province, Peoples R China.;[Li, Zongjie; Kang, Lei; Shao, Donghua; Liu, K; Li, Beibei; Ma, Zhiyong; Liu, Ke; Wei, Jianchao; Xie, Fengyu; Qiu, Yafeng; Ma, ZY; Zhang, Tong; Chen, Mengli] Chinese Acad Agr Sci, Shanghai Vet Res Inst, 518 Ziyue Rd, Shanghai 200241, Peoples R China.;[Kang, Lei; Chen, Mengli] Nanjing Agr Univ, Coll Vet Med, Nanjing, Peoples R China.
通讯机构：
[Li, MX ] H;[Ma, ZY; Liu, K ] C;Hunan Agr Univ, Coll Vet Med, Changsha 410128, Hunan Province, Peoples R China.;Chinese Acad Agr Sci, Shanghai Vet Res Inst, 518 Ziyue Rd, Shanghai 200241, Peoples R China.
关键词：
Heat shock protein 71;Mutation;Porcine reproductive and respiratory syndrome virus nsp2
摘要：
porcine reproductive and respiratory syndrome (PRRS), caused by porcine reproductive and respiratory syndrome virus (PRRSV) infection, is an important swine infectious disease that causes substantial losses worldwide each year. PRRSV is a positive-sense single-stranded RNA virus that is highly susceptible to mutation and recombination, making vaccine and drug research for the disease extremely difficult. In this study, the binding of PRRSV nsp2 to HSP71 protein was detected by using the IP/MS technique. And the inhibitory effect of HSP71 on nsp2 antagonistic activity was validated by measuring NF-kB luciferase reporter. According to stress from inhibitory effects, the amino acid variation profile of PRRSV nsp2 under HSP71 stress was further analyzed using second-generation sequencing. Surprisingly, the results indicated that HSP71 pressure limits the random mutations of PRRSV nsp2 and maintains the dominant PRRSV strain within the population. Mutant strain showed weaker antagonistic activity and replication capability in cell. These results imply the binding of HSP71 with PRRSV nsp2 may lead to maintain the stability of highly virulent strains of PRRSV.
作者机构：
[Li, Manxiang; Ning, Keming] Hunan Agr Univ, Coll Vet Med, Changsha, Hunan, Peoples R China.;[Zhou, Rushun] Hunan Prov Inst Vet Drugs & Feed Control, Changsha, Hunan, Peoples R China.
通讯机构：
[Li, MX ] H;Hunan Agr Univ, Coll Vet Med, Changsha, Hunan, Peoples R China.
关键词：
aminoglycoside;amoxicillin plus clavulanic acid;beta lactam;cefoxitin;ceftiofur;chloramphenicol;clindamycin;doxycycline;enrofloxacin;erythromycin;gentamicin;linezolid;macrolide;ofloxacin;penicillin derivative;polysaccharide;quinolone;sulfafurazole;tetracycline;vancomycin;antibiotic resistance;Article;bacterium isolate;cluster analysis;matrix assisted laser desorption ionization time of flight mass spectrometry;milk;minimum inhibitory concentration;molecular typing;multidrug resistance;nonhuman;polymerase chain reaction;Staphylococcus aureus
摘要：
Background. Staphylococcus aureus is one of the most important foodborne pathogens in the world and the main cause of dairy cow mastitis. Few studies have investigated the epidemic pedigree of S. aureus of bovine origin in Hunan, China. Therefore, we aimed to analyze the capsular polysaccharides (CP), molecular typing, and antibiotic resistance characteristics of S. aureus isolated from raw milk of dairy farms in Hunan Province. Methods. Between 2018 and 2022, 681 raw milk samples were collected from dairy cows from farms in Changsha, Changde, Shaoyang, Yongzhou, and Chenzhou in Hunan Province. S. aureus was isolated from these samples, and the isolates were subjected to molecular typing, CP typing, and determination of antibiotic resistance through broth dilution and polymerase chain reaction (PCR). Results. From 681 raw milk samples, 76 strains of S. aureus were isolated. The pathogenicity of 76 isolates was determined preliminarily by detecting cp5 and cp8 CP genes. Eighteen types of antimicrobial resistance phenotypes of 76 S. aureus strains were detected by the broth dilution method, and 11 kinds of related resistance genes were amplified by PCR. The S. aureus isolates had CP5 (42.10%) and CP8 (57.89%). S. aureus had a multiple antimicrobial resistance rate of 26.75%. The isolated strains had the highest resistance rate to penicillin (82.89%) and showed varying degrees of resistance to other drugs, but no isolate showed resistance to doxycycline. The 76 isolates all carried two or more antibiotic resistance genes, with a maximum of eight antibiotics resistance genes. FemB was detected in all isolates, but none of isolates carried vanA, ermA, or glrA. The 76 isolates were divided into 22 sequence types (ST) and 20 spa types by MLST and spa typing, and the number of t796-ST7 (n = 15) isolates was the highest, which may be the major epidemic strain of multidrug-resistant S. aureus. Conclusion. The present findings indicate the need to increase production of the CP8 S. aureus vaccine in Hunan Province and strengthen resistance monitoring of t796-ST7 isolates with the prevalent molecular type of multi-drug resistant strains. The use of β-lactam, macrolides, and lincosamides should be reduced; doxycycline, sulfonamides, and glycopeptides could be appropriately added to veterinary antibiotics to treat infectious diseases in dairy cows. Copyright 2023 Ning et al.
期刊：
Frontiers in Veterinary Science,2021年8:773912 ISSN：2297-1769
通讯作者：
Li, Man-Xiang;Xiao, Chao-Ting
作者机构：
[Ren, Jie; Fan, Fang-Cheng; Li, Man-Xiang; Ge, Meng; Zhao, Dun; Xie, Yi-Lin; Song, Xiao-Qin] Hunan Agr Univ, Coll Vet Med, Changsha, Peoples R China.;[Li, Man-Xiang; Ge, Meng] Hunan Agr Univ, Coll Vet Med, Hunan Engn Technol Res Ctr Vet Drugs, Changsha, Peoples R China.;[Xiao, Chao-Ting] Hunan Univ, Inst Pathogen Biol & Immunol, Coll Biol, Changsha, Peoples R China.
通讯机构：
[Li, Man-Xiang; Xiao, Chao-Ting] H;Hunan Agr Univ, Coll Vet Med, Changsha, Peoples R China.;Hunan Agr Univ, Coll Vet Med, Hunan Engn Technol Res Ctr Vet Drugs, Changsha, Peoples R China.;Hunan Univ, Inst Pathogen Biol & Immunol, Coll Biol, Changsha, Peoples R China.
关键词：
only plain text;China;complete genome;genetic divergence;PCV3;Prevalence
摘要：
Porcine circovirus type 3 (PCV3), a virus belonging to the Circoviridae family, is considered to be associated with respiratory and neurological signs, cardiac and multisystemic inflammation, reproductive failure, and porcine dermatitis and nephropathy syndrome-like disease in pigs (Sus scrofa). In this study, epidemiological and serological investigations of PCV3 in clinically healthy pigs from different regions of China were performed. Overall, 42.87% (1,101/2,568) of pigs were positive for PCV3 Cap antibody via indirect enzyme-linked immunosorbent assay, with a higher prevalence of PCV3 in multiparous sows (62.22%, 881/1,416) and fattening pigs (28.96%, 159/549) than in suckling piglets (8.96%, 32/357) and nursery pigs (11.79%, 29/246). Of the 2,568 samples, 255 were further tested for PCV3 DNA using real-time polymerase chain reaction, and 63.14% of these were positive, with nearly half having <10 virus copies. The PCV3 DNA and antibody positivity rates were high in the pig serum samples; however, the virus titers and antibody levels were both low, indicating that the humoral immune response of PCV3-infected pigs was weak or lagging, and persistent or repeated infections could occur. Additionally, the complete genomes of 23 PCV3 strains were sequenced and analyzed, which showed nucleotide identities of 98.5~100.0%, 98.6~100.0%, and 99.2~100.0% in the complete genome, open reading frame (ORF)2, and ORF1 sequences, respectively, and amino acid identities of 96.7~100.0% and 99.3~100.0% in the capsid and replicase proteins, respectively. Phylogenetic analysis based on ORF2 nucleotide sequences indicated that the PCV3 strains obtained in the present study could be classified into three sub-clades, with most strains clustered into clade 3c, indicating that PCV3c is the dominant subtype in the regions of China investigated. In general, the present study revealed a high prevalence and high genetic divergence of PCV3 among Chinese pig herds, and indicated that the potential effect of PCV3 on the pig industry may be a concern.
摘要：
为了解湖南省猪源粪肠球菌临床分离株的耐药性及各耐药基因的分布情况,使用K-B法检测了42株猪源粪肠球菌对11种抗生素的敏感性,采用PCR方法检测了粪肠球菌中8种耐药基因的分布情况。结果显示,湖南省临床分离的42株粪肠球菌对大部分的抗生素高度耐药,对四环素、氯霉素、苯唑青霉素、红霉素、米诺霉素、左氧氟沙星、高浓度庆大霉、高浓度链霉素、环丙沙星、万古霉素、青霉素G的耐药率依次为100%、92.9%、88.1%、83.3%、81%、57.1%、52.4%、47.6%、45.2%、31%、11.9%;耐药基因的检出率为Aac（6）’/aph（2’’）97.6%、ant（6）’-Ⅰ90%、aph（3）’-Ⅲ76.2%、tet M 90.5%、erm B 73.8%、Van A 4.8%、Van B 54.8%、Van C 88.1%。从表型与基因型共同分析粪肠球菌的耐药性,发现粪肠球菌的多耐药性严重,其耐药表型与耐药基因并不完全一致。
