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1.
PLoS One ; 16(10): e0257920, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34618810

RESUMO

Tuberculosis (TB), a contagious disease mainly caused by Mycobacterium tuberculosis (M. tb), Mycobacterium bovis (M. bovis), and Mycobacterium caprae (M. caprae), poses a major global threat to the health of humans and many species of animals. Developing an ante-mortem detection technique for different species would be of significance in improving the surveillance employing a One Health strategy. To achieve this goal, a universal indirect ELISA was established for serologically detecting Mycobacterium tuberculosis complex infection for multiple live hosts by using a fusion protein of MPB70, MPB83, ESAT6, and CFP10 common in M. tb, M. bovis, and M. caprae as the coating antigen (MMEC) and HRP-labeled fusion protein A and G as a secondary antibody. After testing the known positive and negative sera, the receiver operating characteristic curves were constructed to decide the cut-off values. Then, the diagnostic sensitivity and specificity of MMEC/AG-iELISA were determined as 100.00% (95% CI: 96.90%, 100.00%) and 100.00% (95% CI: 98.44%, 100.00%) for M. bovis infection of cattle, 100.00% (95% CI: 95.00%, 100.00%) and 100.0% (95% CI: 96.80%, 100.00%) for M. bovis infection of sheep, 90.74% (95% CI: 80.09%, 95.98%) and 98.63% (95% CI: 95.14%, 99.76%) for M. bovis infection of cervids, 100.00% (95% CI: 15.81%, 100.00%) and 98.81% (95% CI: 93.54%, 99.97%) for M. bovis infection of monkeys, 100.00% (95% CI: 86.82%, 100.00%) and 94.85% (95% CI: 91.22%, 97.03%) for M. tb infection of humans. Furthermore, this MMEC/AG-iELISA likely detects M. caprae infection in roe deer. Thus this method has a promising application in serological TB surveillance for multiple animal species thereby providing evidence for taking further action in TB control.

2.
Int J Mol Sci ; 22(18)2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34575880

RESUMO

Escherichia coli and Staphylococcus aureus are two common pathogenic microorganisms that cause mastitis in dairy cows. They can cause clinical mastitis and subclinical mastitis. In recent studies, lncRNAs have been found to play an important role in the immune responses triggered by microbial inducers. However, the actions of lncRNAs in bovine mastitis remain unclear. The purpose of this study was to investigate the effects of bovine mammary epithelial cell injuries induced by treatment with E. coli and S. aureus, and to explore the lncRNA profile on cell injuries. The lncRNA transcriptome analysis showed a total of 2597 lncRNAs. There were 2234 lncRNAs differentially expressed in the E. coli group and 2334 in the S. aureus group. Moreover, we found that the E. coli and S. aureus groups of maternal genes targeted signaling pathways with similar functions according to KEGG and GO analyses. Two lncRNA-miRNA-mRNA interaction networks were constructed in order to predict the potential molecular mechanisms of regulation in the cell injuries. We believe that this is the first report demonstrating the dysregulation of lncRNAs in cells upon E. coli and S. aureus infections, suggesting that they have the potential to become important diagnostic markers and to provide novel insights into controlling and preventing mastitis.

3.
Prev Vet Med ; 196: 105477, 2021 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-34482152

RESUMO

Abattoir surveillance is an integral component of a bovine tuberculosis (bTB) eradication programme. The objective of this study was to determine the prevalence of bTB among culled adult dairy cows in Wuhan, China and to further assess two diagnostic procedures as an adjunct to the confirmation of M. bovis in animals with TB-like lesions. The study was conducted in an abattoir located in Wuhan, China over a period of 41 days from June to July 2019. A total of 171 culled adult dairy cows were sampled and inspected, and blood samples collected from 134 of these. The viscera and lymph nodes of the carcasses were visually inspected and palpated for TB-like lesions. A total of 28.1 % (48/171) of the carcasses had gross TB-like lesions. 89.6 % (43/48) of the animals with TB-like lesions were positive to a PCR procedure for bTB. The sensitivity and specificity for post-mortem examination for TB-like lesions using a Bayesian latent class analysis model was estimated to be 60.8 % and 86.6 %, respectively. A seroprevalence of 20.9 % (28/134) was recorded for antibody response to M. bovis antigens MPB70 and MPB83 based on an ELISA procedure. There was a low-moderate agreement between the ELISA and PCR results in the detection of bTB (Kappa = 0.46, 95 % CI: 0.24-0.67). The study confirms a high prevalence of bTB among culled adult dairy cows in the abattoir and highlights the need to implement surveillance for bTB based on post-mortem examination and ELISA and PCR methods in association with backward tracing of infected dairy herds.

4.
J Gen Virol ; 102(8)2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34424158

RESUMO

Bovine astrovirus (BoAstV) belongs to genus Mamastravirus (MAstV). It can be detected in the faeces of both diarrhoeal and healthy calves. However, its prevalence, genetic diversity, and association with cattle diarrhoea are poorly understood. In this study, faecal samples of 87 diarrhoeal and 77 asymptomatic calves from 20 farms in 12 provinces were collected, and BoAstV was detected with reverse transcription-polymerase chain reaction (RT-PCR). The overall prevalence rate of this virus in diarrhoeal and asymptomatic calves was 55.17 % (95 % CI: 44.13, 65.85 %) and 36.36 % (95 % CI: 25.70, 48.12 %), respectively, indicating a correlation between BoAstV infection and calf diarrhoea (OR=2.15, P=0.024). BoAstV existed mainly in the form of co-infection (85.53 %) with one to five of nine viruses, and there was a strong positive correlation between BoAstV co-infection and calf diarrhoea (OR=2.83, P=0.004). Binary logistic regression analysis confirmed this correlation between BoAstV co-infection and calf diarrhoea (OR=2.41, P=0.038). The co-infection of BoAstV and bovine rotavirus (BRV) with or without other viruses accounted for 70.77 % of all the co-infection cases. The diarrhoea risk for the calves co-infected with BoAstV and BRV was 8.14-fold higher than that for the calves co-infected with BoAstV and other viruses (OR=8.14, P=0.001). Further, the co-infection of BoAstV/BRV/bovine kobuvirus (BKoV) might increase the risk of calf diarrhoea by 14.82-fold, compared with that of BoAstV and other viruses (OR=14.82, P <0.001). Then, nearly complete genomic sequences of nine BoAstV strains were assembled by using next-generation sequencing (NGS) method. Sequence alignment against known astrovirus (AstV) strains at the levels of both amino acids and nucleotides showed a high genetic diversity. Four genotypes were identified, including two known genotypes MAstV-28 (n=3) and MAstV-33 (n=2) and two novel genotypes designated tentatively as MAstV-34 (n=1) and MAstV-35 (n=3). In addition, seven out of nine BoAstV strains showed possible inter-genotype recombination and cross-species recombination. Therefore, our results increase the knowledge about the prevalence and the genetic evolution of BoAstV and provide evidence for the association between BoAstV infection and calf diarrhoea.


Assuntos
Infecções por Astroviridae , Doenças dos Bovinos , Coinfecção , Diarreia , Animais , Animais Recém-Nascidos/virologia , Infecções por Astroviridae/epidemiologia , Infecções por Astroviridae/veterinária , Infecções por Astroviridae/virologia , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/virologia , China/epidemiologia , Coinfecção/epidemiologia , Coinfecção/veterinária , Coinfecção/virologia , Diarreia/epidemiologia , Diarreia/veterinária , Diarreia/virologia , Fezes/virologia , Prevalência
5.
Int J Mol Sci ; 22(12)2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-34200743

RESUMO

Mastitis is a common disease in dairy cows that is mostly caused by E. coli, and it brings massive losses to the dairy industry. N6-Methyladenosine (m6A), a methylation at the N6 position of RNA adenine, is a type of modification strongly associated with many diseases. However, the role of m6A in mastitis has not been investigated. In this study, we used MeRIP-seq to sequence the RNA of bovine mammary epithelial cells treated with inactivated E. coli for 24 h. In this in vitro infection model, there were 16,691 m6A peaks within 7066 mRNA transcripts in the Con group and 10,029 peaks within 4891 transcripts in the E. coli group. Compared with the Con group, 474 mRNAs were hypermethylated and 2101 mRNAs were hypomethylated in the E. coli group. Biological function analyses revealed differential m6A-modified genes mainly enriched in the MAPK, NF-κB, and TGF-ß signaling pathways. In order to explore the relationship between m6A and mRNA expression, combined MeRIP-seq and mRNA-seq analyses revealed 212 genes with concomitant changes in the mRNA expression and m6A modification. This study is the first to present a map of RNA m6A modification in mastitis treated with E. coli, providing a basis for future research.


Assuntos
Adenosina/análogos & derivados , Metilação de DNA , Células Epiteliais/metabolismo , Infecções por Escherichia coli/veterinária , Regulação da Expressão Gênica , Glândulas Mamárias Animais/metabolismo , Mastite Bovina/genética , Adenosina/química , Animais , Bovinos , Células Epiteliais/imunologia , Células Epiteliais/microbiologia , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/genética , Infecções por Escherichia coli/imunologia , Feminino , Perfilação da Expressão Gênica , Glândulas Mamárias Animais/imunologia , Glândulas Mamárias Animais/microbiologia , Mastite Bovina/imunologia , Mastite Bovina/microbiologia
6.
ACS Sens ; 6(7): 2574-2583, 2021 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-34156832

RESUMO

The use of color-encoded microspheres for a bead-based assay has attracted increasing attention for high-throughput multiplexed bioassays. A fluorescent PCC 6803@ZIF-8 composite was prepared as a bead-based assay platform by a self-assembled zeolitic imidazolate framework (ZIF-8) on the surface of inactivated PCC 6803 cells. The composite fluorescence owing to the presence of pigment proteins in PCC 6803 could be gradually bleached with the prolongation of the ultraviolet light irradiation time. The composites with different fluorescence intensities were therefore obtained as encoded microspheres for the multiplexed assay. ZIF-8 provides a stable, rigid shell and a large specific surface area for composites, which prevent the composites from breakage during use and storage, simplify the protein immobilization procedure, reduce non-specific adsorption, and enhance the detection sensitivity. The encoded composites were successfully used to detect multiple DNA insertion sequences of Mycobacterium tuberculosis. The presented strategy offers an innovative color-encoding method for high-throughput multiplexed bioassays without the need of using chemically synthesized fluorescent materials.


Assuntos
Zeolitas , Adsorção , Bioensaio , Biomarcadores , Microesferas
7.
Vaccine ; 39(30): 4184-4189, 2021 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-34127292

RESUMO

Infectious diseases can have a major impact on the profitability of the cattle industry. To determine the occurrence of bovine infectious diseases in China and the adoption of vaccination to control them, a national-wide questionnaire and focus group meeting were performed. The questionnaire was administered to 189 farmers including 93 dairy farmers, 80 beef cattle farmers and 16 yak farmers. Since it is compulsory to vaccinate cattle against foot and mouth disease, the coverage of vaccination to this disease was the highest (100% of dairy and yak farms and 92.5% of beef farms). However, the implementation of vaccination against other diseases was vastly different between cattle types with less than 50% of farms adopting vaccination (except brucellosis vaccine in yak farms). In a focus group meeting of 36 cattle experts on the key issues affecting the frequency of infectious diseases in cattle and the vaccination practices adopted on Chinese cattle farms, the lack of effective vaccines against single or multiple pathogens, a lack of tools for the early and correct diagnosis of disease, difficulties in licensing novel vaccines and diagnostic agents, low efficiency in disseminating knowledge on diseases and control products to producers were identified as key issues. In conclusion, except for FMD, the control of most infectious diseases of cattle in China requires improving. Development of improved control measures and diagnostic tests along with the development and implementation of educational material for producers on cattle diseases should be given priority.


Assuntos
Doenças dos Bovinos , Doenças Transmissíveis , Febre Aftosa , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/prevenção & controle , China/epidemiologia , Fazendas , Febre Aftosa/epidemiologia , Febre Aftosa/prevenção & controle , Vacinação/veterinária
8.
Front Immunol ; 12: 619362, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33659004

RESUMO

Mycoplasma bovis causes important diseases and great losses on feedlots and dairy farms. However, there are only a few measures to control M. bovis-related diseases. As in other mycoplasma species, this is predominantly because the virulence related factors of this pathogen are largely unknown. Therefore, in this study, we aimed to identify novel virulence-related factors among the secreted proteins of M. bovis. Using bioinformatic tools to analyze its secreted proteins, we preliminarily predicted 39 secreted lipoproteins, and then selected 11 of them for confirmation based on SignalP scores >0.6 or SceP scores >0.8 and conserved domains. These 11 genes were cloned after gene modification based on the codon bias of Escherichia coli and expressed. Mouse antiserum to each recombinant protein was developed. A western blotting assay with these antisera confirmed that MbovP280 and MbovP475 are strongly expressed and secreted proteins, but only MbovP280 significantly reduced the viability of bovine macrophages (BoMac). In further experiments, MbovP280 induced the apoptosis of BoMac treated with both live M. bovis and MbovP280 protein. The conserved coiled-coil domain of MbovP280 at amino acids 210-269 is essential for its induction of apoptosis. Further, immunoprecipitation, mass spectrometry, and coimmunoprecipitation assays identified the anti-apoptosis regulator αB-crystallin (CRYAB) as an MbovP280-binding ligand. An αß-crystallin knockout cell line BoMac-cryab-, Mbov0280-knockout M. bovis strain T9.297, and its complemented M. bovis strain CT9.297 were constructed and the apoptosis of BoMac-cryab- induced by these strains was compared. The results confirmed that CRYAB is critical for MbovP280 function as an apoptosis inducer in BoMac. In conclusion, in this study, we identified MbovP280 as a novel secreted protein of M. bovis that induces the apoptosis of BoMac via its coiled-coil domain and cellular ligand CRYAB. These findings extend our understanding of the virulence mechanism of mycoplasmal species.


Assuntos
Apoptose , Proteínas de Bactérias/metabolismo , Macrófagos/metabolismo , Infecções por Mycoplasma/genética , Infecções por Mycoplasma/microbiologia , Mycoplasma bovis/fisiologia , Animais , Apoptose/imunologia , Proteínas de Bactérias/imunologia , Proteínas de Bactérias/farmacologia , Bovinos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Genoma Bacteriano , Humanos , Ligantes , Macrófagos/imunologia , Camundongos , Modelos Biológicos , Infecções por Mycoplasma/imunologia , Infecções por Mycoplasma/metabolismo
9.
ACS Infect Dis ; 7(4): 800-810, 2021 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-33705114

RESUMO

The modulation of the interaction between macrophages and Mycobacterium tuberculosis (M.tb) through microRNA during M.tb infection is increasingly capturing the attention of researchers. However, the potential role of microRNA-18b-5p (miR-18b) is not elucidated yet. In this study, miR-18b was found to be downregulated in M.tb-infected macrophage cell lines (THP-1 and RAW264.7) in time- and dose-dependent manners. Furthermore, when the miR-18b mimic and inhibitor and small interfering RNA hypoxia-inducible factor 1α (si-HIF-1α) were transfected into the macrophages separately or in combination, it was found that miR-18b targeted hypoxia-inducible factor 1α (HIF-1α). During M.tb infection, the decrease in the expression of miR-18b facilitated HIF-1α expression, which led to the increased production of pro-inflammatory cytokines, such as IL-6, resulting in decreased bacterial survival in the host cells. Moreover, the phosphorylation of p38 MAPK and NF-κB p65 was activated by the miR-18b inhibitor. Our findings expand the current understanding of the M.tb-cell interaction mechanism and provide a potential target to control M.tb infection.


Assuntos
Macrófagos , MicroRNAs , Mycobacterium tuberculosis , Animais , Citocinas/genética , Citocinas/metabolismo , Regulação para Baixo , Humanos , Macrófagos/metabolismo , Macrófagos/microbiologia , Camundongos , MicroRNAs/genética , Células RAW 264.7 , Células THP-1
10.
Infect Genet Evol ; 89: 104715, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33434703

RESUMO

Rotaviruses (RVs) account for severe diarrhea in children and young animals globally. In the current study, the fecal samples of diarrheic calves from a beef farm in Inner Mongolia were screened for RVA by ELISA and RT-PCR, followed by culture of three positive RVA samples in the MA-104 cell line. After 10 blind passages, cytopathic effects (CPE) appeared as detachment, granulation, and clustering of the inoculated cells. The virus isolates were identified by RT-PCR (VP6 gene RVA) and ESI-LC-MS/MS for whole protein sequencing. The protein sequences demonstrated the presence of two strains from species A rotavirus and one RVB strain; RVA/Cow-tc/CHN/35333/2019/G6P[5] was mixed with one RVB strain (RVB/Cow-tc/CHN/35334/2019/G5P[3]) in two samples, and RVA/Cow-tc/CHN/10927/2019/G8P[7] was found in one sample. They are of genotype constellations (G6-P[5]-I2-R2-C2-M2-A3-N2-T6-E2-H3), (G8-P[7]-I5-R1-C1- M2-A1-N1-T1-E1-H1), and (G5-P[3]-I3-R5-C5-A5-N4-H5), respectively. Besides, phylogenetic analysis of the obtained sequences demonstrated viral evolution.

11.
Transbound Emerg Dis ; 2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33406306

RESUMO

Cryptosporidium parvum is a major zoonotic pathogen responsible for outbreaks of severe diarrhoea in humans and calves. Almost all investigations of cryptosporidiosis outbreaks caused by C. parvum have focused on its IIa subtype family in industrialized nations. From December 2018 to April 2019, approximately 200 neonatal calves on a large cattle farm in Hebei Province, China, were diagnosed with watery diarrhoea and over 40 died. To investigate the cause of the outbreak, faecal samples were taken during and after the outbreak from neonatal calves of ≤4 weeks of age (n = 40 and n = 56) and older calves of 4-24 weeks of age (n = 79 and n = 38). A total of 18 faecal samples collected from ill calves at the peak of the outbreak were analysed for four common enteric pathogens using an enzymatic immunoassay (EIA). In addition, 75 samples from neonatal calves were tested for rotavirus by EIA. All samples were analysed for Cryptosporidium spp. using PCR and sequencing techniques. Of the initial 18 samples from sick calves, ten were positive for C. parvum, five for rotavirus, and one for coronavirus. The overall prevalence of rotavirus in neonatal calves was 20.0% (15/75), with no significant differences during and after the outbreak. In contrast, Cryptosporidium parvum infections were significantly higher during the outbreak (60.0%, 24/40) than after the outbreak (30.4%, 17/56; p = .004). Cryptosporidium parvum infection was associated with the presence of watery diarrhoea in neonatal calves (OR = 11.19), while no association was observed between C. bovis infection and diarrhoea. All C. parvum isolates were identified as subtype IIdA20G1. This is one of the few reports of outbreaks of severe diarrhoea caused by C. parvum IId subtypes in calves. More attention should be directed towards the dissemination of C. parvum in China.

12.
Transbound Emerg Dis ; 68(3): 1216-1228, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32767733

RESUMO

Eliminating rabies is challenging in many developing countries, especially in rural areas. In contrast to the annual decline of human cases in China in last decade, the incidence of rabies in livestock has been increasingly reported. This paper reports the rabies outbreaks in beef cattle (Angus) in Shaanxi Province, China, which caused 31 and 5 deaths at an attack rate of 19.4% (95% CI: 13.6%-26.4%) and 0.25% (95% CI: 0.1%-0.6%) in a satellite cow farm (farm A) and a core intensive farm (farm B), respectively. The rabies infection was confirmed by several laboratory tests, and rabies virus (RABV) strains SXBJ15 and SXYL15 were isolated and characterized from farm A and B, respectively. The two strains were found to have a high genomic sequence similarity to the dog-associated China clade I strains previously identified in the neighbouring area. SXBJ15 was shown to have a higher mouse pathogenicity (1.07) than SXYL15 (0.45). RABV was also detected in the saliva and salivary glands from the affected cattle. The potential causes were investigated on the farm, and the biosecurity scores were 20 and 64 (a full score of 82) for farms A and B, respectively. The rabies infection is likely to result from rabid free-roaming dogs (FRDs). On farm A with more cow deaths, the rabies transmission between animals can be attributed to the improper disposal of aborted foetuses and placental materials as a food source for rabid FRDs, high stocking density and drinking water sharing. Additionally, vaccinating cattle with a canine vaccine was shown to help stop the spread of rabies in herds. These results indicate that the occurrence of RABV on cattle farms can be prevented by improving biosecurity measures to control the entry of rural FRDs on the farm and immunizing farm cattle against rabies.


Assuntos
Doenças dos Bovinos/epidemiologia , Surtos de Doenças/veterinária , Fazendas , Vírus da Raiva/genética , Vírus da Raiva/isolamento & purificação , Raiva/veterinária , Animais , Bovinos/virologia , Doenças dos Bovinos/prevenção & controle , Doenças dos Bovinos/transmissão , Doenças dos Bovinos/virologia , China/epidemiologia , Doenças do Cão/epidemiologia , Cães , Feminino , Genoma Viral , Humanos , Gado , Camundongos , Placenta , Gravidez , Raiva/epidemiologia , Raiva/transmissão , Raiva/virologia , Vacinas Antirrábicas , Vírus da Raiva/patogenicidade
13.
Biochem Biophys Res Commun ; 534: 822-829, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33239173

RESUMO

Bovine lactoferrin peptide has been shown to be a broad-spectrum antimicrobial peptide. Based on the relationship between the structure and function of antimicrobial peptides, the antimicrobial peptide databases and protein analysis software were used to optimize the design of bovine lactoferricin peptide (LfcinB). The designed bovine lactoferricin-derived peptide (LfcinBD) gene fragment was inserted into a pPIC9K-His plasmid to construct a recombinant expression vector. After linearization of the Recombinant plasmid, Pichia pastoris GS115 cells were transfected with linearized recombinant plasmid by using electroporation and LfcinBD gene expression was induced with methanol. After the fermentation, supernatant was separated by low-temperature high-speed centrifugation. Ultrafiltration and freeze drying of the fermentation supernatant were performed, purified. Experimental results showed that the LfcinBD had stronger bacteriostatic activity against Staphylococcus aureus than the natural bovine lactoferrin peptide (LfcinB) produced under the same fermentation conditions. The effective expression of the optimized bovine lactoferricin-derived peptide was detected using SDS-PAGE electrophoresis. This study lays the foundation for further exploration to improve the biological activities of antimicrobial peptides.


Assuntos
Lactoferrina/química , Peptídeos/genética , Peptídeos/metabolismo , Peptídeos/farmacologia , Pichia/genética , Oxirredutases do Álcool/genética , Antibacterianos/química , Antibacterianos/farmacologia , Eletroporação , Fermentação , Testes de Sensibilidade Microbiana , Peptídeos/química , Plasmídeos/genética , Reação em Cadeia da Polimerase , Proteínas Citotóxicas Formadoras de Poros/genética , Proteínas Citotóxicas Formadoras de Poros/farmacologia , Regiões Promotoras Genéticas , Engenharia de Proteínas/métodos , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacologia , Transfecção
14.
Transbound Emerg Dis ; 2020 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-33118288

RESUMO

Brucellosis has re-emerged in China in recent years, resulting in an increasing health burden and economic losses for humans and the livestock industries. This study integrated data from human and livestock brucellosis surveillance systems to explore the changing epidemiology of brucellosis from 2004 to 2018 in China. A total of 524,980 human cases of brucellosis were reported, with the average annual incidence in humans being significantly higher for the period 2012-2018 than for 2004-2011 (3.3 vs. 1.9 per 100,000 residents). An autoregressive integrated moving average (ARIMA) model predicted an upward trend in the monthly incidence of brucellosis in humans in 2019 and 2020. Characteristics including being male, aged 45-54 years, working in the livestock industries, and residing in the northern provinces of China increased the risk of people contracting brucellosis. The percentage of provinces with infected people increased from 67.7% (21/31) in 2004 to all provinces in 2018. A total of 29,115 outbreaks were reported in livestock from 2004 to 2018, with 443,883 seropositive animals although only 381,224 (85.9%) of these were culled. The monthly incidence of brucellosis in humans was strongly positively correlated (r = .539, p < .001) with the number of outbreaks of brucellosis in livestock reported 3 months prior to the human cases. At the provincial level, the annual incidence of brucellosis in humans was significantly positively correlated with the sheep population (r = .786, p < .01). In conclusion, brucellosis in humans and livestock has been spreading in mainland China in the past decade. A more active surveillance of brucellosis in both livestock and humans in China should be coordinated and adjusted by adopting an evidence-based 'One Health' approach, particularly in high-risk regions and livestock industries.

15.
Pathogens ; 9(10)2020 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-33086687

RESUMO

The objective of this study was to estimate the fecal carriage of Salmonella spp. among culled adult dairy cows presented to an abattoir in Wuhan, China and to evaluate their antimicrobial resistance profiles. Rectal swabs from 138 culled cows were cultured. Laboratory analysis involved the identification of Salmonella, the susceptibility assessment and the presence of Extended Spectrum ß-lactamases and mcr genes in the isolates. An overall prevalence of Salmonella of 29.0% was recorded with 63.4% (26/41) and 2.4% (1/41) of the isolates identified as S. Typhimurium and S. Dublin, respectively. The occurrence of Salmonella was higher (odd ratios: 3.3) in culled cows originating from the northeast zone of China than cows originating from the central and north zones. Twenty multi-drug resistant strains (resistant to three or more antimicrobial agents) were detected (48.8%) and overall, a high resistance to ampicillin (36/41) and tetracycline (15/41) was observed. Extended Spectrum ß-lactamases phenotypes were found in 7/41 isolates, of which all contained the blaCTX-M resistance gene, and no mcr genes were found by polymerase chain reaction. The high prevalence of Salmonella fecal carriage and antimicrobial resistance may contribute to an increased risk of Salmonella transmission to food.

16.
Pathogens ; 9(9)2020 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-32967149

RESUMO

Mycoplasma bovis is a major pathogen, responsible for bovine respiratory diseases worldwide. The present lack of effective control measures leaves cattle owners at considerable perpetual risk of M. bovis outbreaks. In this study, we identified M. bovis secreted immunogenic proteins in silico as potential candidates for novel diagnostic agents and vaccines. We used immunoinformatics to analyze 438 M. bovis proteins previously identified with a label-free proteomics analysis of virulent M. bovis HB0801 (P1) and its attenuated P150 strains. The subcellular localization of these proteins was preliminarily screened and 59 proteins were found to be secreted extracellular proteins. Twenty-seven of these proteins contained a large number of predictive T-cell epitopes presented by major histocompatibility complex (MHC) class I and II molecules. Twenty-two of these 27 proteins had a high number of conformational B-cell epitopes, predicted from the corresponding 3D structural templates, including one unique to P1, two unique to P150, and 19 common to both strains. Five proteins were selected for further validation, and two of these, MbovP274 and MbovP570, were successfully expressed and purified. Both were confirmed to be secretory and highly immunogenic proteins that induced a mouse antibody response, reacted with cattle serum positive for M. bovis infection, and significantly increased the production of interleukin 8 (IL-8), IL-12 and interferon γ (IFN-γ) during the secretion of these three cytokines by both M. bovis mutants of these genes. These results should be useful in the development of novel immunological agents against M. bovis infection.

17.
Microb Pathog ; 148: 104456, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32810556

RESUMO

Tripartite motif 25 (TRIM25) is a TRIM family member which is involved in innate immunity. However, its role in the modulation of host defense against Mycobacterium tuberculosis (M.tb) infection has not been investigated. Therefore, this study aimed to demonstrate the significance of TRIM25 in the regulation of macrophage responses to M.tb infection. TRIM25 was found to be significantly overexpressed (3.476-fold) in peripheral blood mononuclear cells (PBMCs) of 67 patients with pulmonary tuberculosis compared with 48 healthy controls. TRIM25 expression was enhanced following M.tb infection of RAW264.7 cells, a macrophage cell line. Overexpression of TRIM25 in M.tb-infected RAW264.7 cells led to a significant increase in phosphorylated p38 levels; however, the production of IL-6, IL-1ß, and TNF-α were significantly reduced. Finally, M.tb intracellular survival increased by 90% at 12 h post-infection (PI) (p < 0.01). To validate the previous results, TRIM25 levels in M.tb-infected RAW264.7 macrophages were down-regulated using small interfering RNA (siRNA). Therefore, it was concluded that TRIM25 promotes intracellular survival of M.tb in RAW264.7 cells, likely by enhancing p38 pathways and thereby inhibiting the production of proinflammatory cytokines. These results contribute to the further understanding of the host defense against M.tb infection.


Assuntos
Mycobacterium tuberculosis , Tuberculose , Humanos , Leucócitos Mononucleares , Transdução de Sinais , Fatores de Transcrição/genética , Proteínas com Motivo Tripartido/genética , Ubiquitina-Proteína Ligases , Regulação para Cima
18.
Prev Vet Med ; 182: 105086, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32673936

RESUMO

This study was designed to compare a milk I-ELISA with a serum ELISA for the diagnosis of brucellosis in dairy cattle and then to use the milk I-ELISA to determine the prevalence and incidence of brucellosis in dairy herds in Hubei Province, China. The two tests were shown to have good agreement with a Cohen's kappa statistic of 0.747 (p < 0.001) when 147 animals originating from 4 dairy herds in the province were tested. The results of Bayesian Latent Class Analysis estimated that the sensitivity and specificity of the milk I-ELISA under field conditions were 87.2 % and 92.0 %, respectively. An epidemiological survey based on the milk I-ELISA was then conducted in 3091 cows from 15 commercial dairy herds from January to July 2018 in Hubei Province. The animal level real prevalence varied from 34.9 % (95 % CI: 28.5, 41.8) to 51.4 % (95 % CI: 48.2, 54.6) in the 15 herds tested. Most farms (93.3 %) tested contained at least one test-positive animal. As only ten farms met the inclusion criteria for the calculation of incidence risk, the overall real incidence risk in 10 of these farms was 0.4 % (95 % CI: 0.1, 1.2) per 3 months, which highlights the potential for spread of the disease within infected herds. It is concluded that the milk I-ELISA test could be used as a rapid screening test for brucellosis in unvaccinated dairy cows and, given the high occurrence of bovine brucellosis in this study, an effective prevention and control program needs to be developed and implemented in Hubei Province, China.


Assuntos
Brucelose Bovina/epidemiologia , Testes Diagnósticos de Rotina/veterinária , Ensaio de Imunoadsorção Enzimática/veterinária , Leite/química , Soro/química , Animais , Brucelose Bovina/diagnóstico , Bovinos , China/epidemiologia , Indústria de Laticínios , Testes Diagnósticos de Rotina/instrumentação , Ensaio de Imunoadsorção Enzimática/instrumentação , Incidência , Prevalência
19.
Int Immunopharmacol ; 86: 106697, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32585608

RESUMO

Mastitis is one of the most common diseases among dairy cows. There is still much debate worldwide as to whether antibiotic therapy should be given to dairy cows, or if natural products should be taken as a substitute for antibacterial therapy. As the antibiotic treatment leads to the bacterial resistance and drug residue in milk, introducing natural products for mastitis is becoming a trend. This study investigates the mechanisms of the protective effects of the natural product gambogic acid (GA) in lipopolysaccharide (LPS)-induced mastitis. For in vitro treatments, it was found that GA reduced IL-6, TNF-α, and IL-1ß levels by inhibiting the phosphorylation of proteins in the nuclear factor κB (NF-κB) and the mitogen-activated protein kinase (MAPK) pathway. GA also maintained a stable membrane mitochondrial potential and inhibited the overproduction of reactive oxygen species, which protected the cells from apoptosis. On the other hand, in vivo treatments with GA were found to reduce pathological symptoms markedly, and protected the blood-milk barrier from damage induced by LPS. The results demonstrate that GA plays a vital role in suppressing inflammation, alleviating the apoptosis effect, and protecting the blood-milk barrier in mastitis induced by LPS. Thus, these results suggest that the natural product GA plays a potential role in mastitis treatment.


Assuntos
Anti-Inflamatórios/farmacologia , Apoptose/efeitos dos fármacos , Glândulas Mamárias Animais/efeitos dos fármacos , Mastite/tratamento farmacológico , Xantonas/farmacologia , Animais , Anti-Inflamatórios/uso terapêutico , Caspase 3/metabolismo , Caspase 9/metabolismo , Linhagem Celular , Citocinas/metabolismo , Modelos Animais de Doenças , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/imunologia , Feminino , Inflamação/tratamento farmacológico , Lipopolissacarídeos/toxicidade , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Glândulas Mamárias Animais/imunologia , Glândulas Mamárias Animais/patologia , Glândulas Mamárias Animais/ultraestrutura , Mastite/induzido quimicamente , Mastite/imunologia , Mastite/patologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Subunidade p50 de NF-kappa B/metabolismo , Fosforilação/efeitos dos fármacos , Gravidez , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Xantonas/uso terapêutico
20.
PLoS Pathog ; 16(6): e1008661, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32598377

RESUMO

Mycoplasmas are host-restricted prokaryotes with a nearly minimal genome. To overcome their metabolic limitations, these wall-less bacteria establish intimate interactions with epithelial cells at mucosal surfaces. The alarming rate of antimicrobial resistance among pathogenic species is of particular concern in the medical and veterinary fields. Taking advantage of the reduced mycoplasma genome, random transposon mutagenesis was combined with high-throughput screening in order to identify key determinants of mycoplasma survival in the host-cell environment and potential targets for drug development. With the use of the ruminant pathogen Mycoplasma bovis as a model, three phosphodiesterases of the DHH superfamily were identified as essential for the proliferation of this species under cell culture conditions, while dispensable for axenic growth. Despite a similar domain architecture, recombinant Mbov_0327 and Mbov_0328 products displayed different substrate specificities. While rMbovP328 protein exhibited activity towards cyclic dinucleotides and nanoRNAs, rMbovP327 protein was only able to degrade nanoRNAs. The Mbov_0276 product was identified as a member of the membrane-associated GdpP family of phosphodiesterases that was found to participate in cyclic dinucleotide and nanoRNA degradation, an activity which might therefore be redundant in the genome-reduced M. bovis. Remarkably, all these enzymes were able to convert their substrates into mononucleotides, and medium supplementation with nucleoside monophosphates or nucleosides fully restored the capacity of a Mbov_0328/0327 knock-out mutant to grow under cell culture conditions. Since mycoplasmas are unable to synthesize DNA/RNA precursors de novo, cyclic dinucleotide and nanoRNA degradation are likely contributing to the survival of M. bovis by securing the recycling of purines and pyrimidines. These results point toward proteins of the DHH superfamily as promising targets for the development of new antimicrobials against multidrug-resistant pathogenic mycoplasma species.


Assuntos
Proteínas de Bactérias/metabolismo , Mycoplasma bovis/enzimologia , Pirofosfatases/metabolismo , Ribonucleases/metabolismo , Animais , Proteínas de Bactérias/genética , Linhagem Celular , Camundongos , Camundongos Endogâmicos BALB C , Mycoplasma bovis/genética , Pirofosfatases/genética , Ribonucleases/genética
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