Publications by authors named "Tamaki Okabayashi"

71 Publications

Development and validation of indirect ELISA for antibody detection against different protein antigens of porcine epidemic diarrhea virus in the colostrum and milk of sows.

J Immunol Methods 2021 Mar 26:113045. Epub 2021 Mar 26.

Department of Veterinary Microbiology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok 10330, Thailand. Electronic address:

The objectives of this study are to develop and optimize indirect ELISA based on three coating antigens of porcine epidemic diarrhea virus (PEDV), recombinant spike (S12), nucleocapsid (N), and whole viral (WV) proteins, for the detection of IgG and IgA antibodies in colostrum and milk and to evaluate the diagnostic sensitivity (DSe) and diagnostic specificity (DSp) of the assay as a diagnostic method. Colostrum (n = 347) and milk (n = 272) samples from sows were employed in this assay. Indirect ELISA based on three coating antigens was assessed by receiver operating characteristic (ROC) curve analysis with a virus neutralization (VN) test as a reference method, and the cutoff value for calculating DSe and DSp was determined. S12-ELISA showed higher DSe and DSp of IgG and IgA detection compared to N- and WV-ELISA in both colostrum and milk samples. Moreover, S12-ELISA showed perfect agreement and a high correlation with the VN test, which was better than the N- and WV-ELISA for both IgG and IgA detection in colostrum and milk. In contrast, N-ELISA showed lower DSe and DSp compared to S12- and WV-ELISA, along with a correlation with VN and substantial agreement with the VN test. Nevertheless, our developed ELISAs have accuracy for repeatability in both inter- and intra-assay variation. Overall, this research demonstrates that S12-ELISA is more suitable than WV- and N-ELISA to detect IgG and IgA antibodies against PEDV from both colostrum and milk samples.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jim.2021.113045DOI Listing
March 2021

Identification of and Related Enterobacteriaceae and Examination of Their Phenotypic Antimicrobial Resistance Patterns: A Pilot Study at A Wildlife-Livestock Interface in Lusaka, Zambia.

Antibiotics (Basel) 2021 Feb 26;10(3). Epub 2021 Feb 26.

Department of Veterinary Science, Faculty of Agriculture, University of Miyazaki, Miyazaki 889-2192, Japan.

A cross-sectional study was used to identify and assess prevalence and phenotypic antimicrobial resistance (AMR) profiles of and other enterobacteria isolated from healthy wildlife and livestock cohabiting at a 10,000 acres game ranch near Lusaka, Zambia. Purposive sampling was used to select wildlife and livestock based on similarities in behavior, grazing habits and close interactions with humans. Isolates ( = 66) from fecal samples collected between April and August 2018 ( = 84) were examined following modified protocols for bacteria isolation, biochemical identification, molecular detection, phylogenetic analysis, and antimicrobial susceptibility testing by disc diffusion method. Data were analyzed using R software, Genetyx ver.12 and Mega 6. Using Applied Profile Index 20E kit for biochemical identification, polymerase chain reaction assay and sequencing, sixty-six isolates were identified to species level, of which (72.7%, 48/66), (1.5%, 1/66), (22.7%, 14/66), (1.5%, 1/66) and (1.5%, 1/66), and their relationships were illustrated in a phylogenetic tree. Phenotypic antimicrobial resistance or intermediate sensitivity expression to at least one antimicrobial agent was detected in 89.6% of the , and 73.3% of the isolates. The isolates exhibited the highest resistance rates to ampicillin (27%), ceftazidime (14.3%), cefotaxime (9.5%), and kanamycin (9.5%). Multidrug resistance (MDR) was detected in 18.8% of isolates while only 13.3% isolates showed MDR. The MDR was detected among isolates from impala and ostrich (wild animals in which no antimicrobial treatment was used), and in isolates from cattle, pigs, and goats (domesticated animals). This study indicates the possible transmission of drug-resistant microorganisms between animals cohabiting at the wildlife-livestock interface. It emphasizes the need for further investigation of the role of wildlife in the development and transmission of AMR, which is an issue of global concern.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/antibiotics10030238DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7996741PMC
February 2021

Bovine respiratory coronavirus enhances bacterial adherence by upregulating expression of cellular receptors on bovine respiratory epithelial cells.

Vet Microbiol 2021 Apr 17;255:109017. Epub 2021 Feb 17.

Department of Veterinary Science, Faculty of Agriculture, University of Miyazaki, Miyazaki, 889-2192, Japan; Graduate School of Medicine and Veterinary Medicine, University of Miyazaki, Miyazaki, 889-2192, Japan; Center for Animal Disease Control, University of Miyazaki, Miyazaki, 889-2192, Japan. Electronic address:

Bovine coronavirus (BCoV) is one of the agents causing bovine respiratory disease complex (BRDC), with single infection tending to be mild to moderate; the probability of developing pneumonia in BRDC may be affected by viral and bacterial combinations. Previously, we reported that bovine respiratory syncytial virus (BRSV) infection enhances adherence of Pasteurella multocida (PM) to cells derived from the bovine lower respiratory tract but that BRSV infection in cells derived from the upper respiratory tract reduces PM adherence. In this study, we sought to clarify whether the modulation of bacterial adherence to cells derived from the bovine upper and lower respiratory tract is shared by other BRDC-related viruses by infecting bovine epithelial cells from the trachea, bronchus and lung with BCoV and/or PM. The results showed that cells derived from both the upper and lower respiratory tract were susceptible to BCoV infection. Furthermore, all cells infected with BCoV exhibited increased PM adherence via upregulation of two major bacterial adhesion molecules, intercellular adhesion molecule-1 (ICAM-1) and platelet-activating factor receptor (PAF-R), suggesting that compared with BRSV infection, BCoV infection differentially modulates bacterial adherence. In summary, we identified distinct interaction between bovine respiratory viruses and bacterial infections.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.vetmic.2021.109017DOI Listing
April 2021

Pseudorabies virus infection in hunting dogs in Oita, Japan: Report from a prefecture free from Aujeszky's disease in domestic pigs.

J Vet Med Sci 2021 Apr 15;83(4):680-684. Epub 2021 Feb 15.

Centre for Animal Disease Control, University of Miyazaki, 1-1 Gakuen Kibanadai-nishi, Miyazaki 889-2192, Japan.

We isolated two pseudorabies virus (PRV) isolates (designated OT-1 and OT-2) from two hunting dogs exhibiting neurological manifestations after eating the flesh of wild boar hunted in Oita prefecture, Kyushu Island, Japan. The isolates corresponded to a previously reported PRV (MY-1 strain) isolated from a hunting dog in neighboring Miyazaki prefecture, and it clustered into genotype II based on the glycoprotein C sequence. Our results suggest that this common PRV strain may have been maintained in wild boars on Kyushu Island even though domestic pigs in this area have attained an Aujeszky's disease-free status.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1292/jvms.20-0450DOI Listing
April 2021

Seroprevalence of Severe Fever with Thrombocytopenia Syndrome Virus in Small-Animal Veterinarians and Nurses in the Japanese Prefecture with the Highest Case Load.

Viruses 2021 02 2;13(2). Epub 2021 Feb 2.

Center for Animal Disease Control, University of Miyazaki, Miyazaki 889-2192, Japan.

Severe fever with thrombocytopenia syndrome virus (SFTSV) is the causative agent of SFTS, an emerging tick-borne disease in East Asia, and is maintained in enzootic cycles involving ticks and a range of wild animal hosts. Direct transmission of SFTSV from cats and dogs to humans has been identified in Japan, suggesting that veterinarians and veterinary nurses involved in small-animal practice are at occupational risk of SFTSV infection. To characterize this risk, we performed a sero-epidemiological survey in small-animal-practice workers and healthy blood donors in Miyazaki prefecture, which is the prefecture with the highest per capita number of recorded cases of SFTS in Japan. Three small-animal-practice workers were identified as seropositive by ELISA, but one had a negative neutralization-test result and so was finally determined to be seronegative, giving a seropositive rate of 2.2% (2 of 90), which was significantly higher than that in healthy blood donors (0%, 0 of 1000; < 0.05). The seroprevalence identified here in small-animal-practice workers was slightly higher than that previously reported in other high-risk workers engaged in agriculture and forestry in Japan. Thus, enhancement of small-animal-practice workers' awareness of biosafety at animal hospitals is necessary for control of SFTSV.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/v13020229DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7912989PMC
February 2021

Isolation of Severe Fever with Thrombocytopenia Syndrome Virus from Various Tick Species in Area with Human Severe Fever with Thrombocytopenia Syndrome Cases.

Vector Borne Zoonotic Dis 2021 Feb 3. Epub 2021 Feb 3.

Department of Veterinary Sciences, Faculty of Agriculture, University of Miyazaki, Miyazaki, Japan.

Severe fever with thrombocytopenia syndrome (SFTS), caused by , generally called SFTS virus (SFTSV), is an emerging zoonosis in East Asia. In Japan, 50-100 cases of SFTS have been reported each year since the first case was reported in 2013. SFTS is a tick-borne infectious disease, and SFTSV has been isolated from ticks in China and South Korea. and are considered the primary vectors in Japan. However, the other tick species seldom feeding on humans might also play an important role in maintaining the virus in nature. In this study, we collected ticks on vegetation around the location where two SFTS patients were estimated to have been infected in Miyazaki Prefecture, Japan, isolated live SFTSV, and performed a phylogenetic analysis. A total of 257 ticks were collected, and SFTSV RNA was detected in 19.5% (9/46) of tick pools. A total of 10 infectious SFTSVs were successfully isolated from , , , , and . Furthermore, the whole viral sequences isolated from ticks were highly homologous to sequences isolated from SFTS patients in the same sampling area in the past. These results suggest that SFTSVs are maintained in these tick species in the sampling area and sporadically transmitted to humans. Surveillance of SFTSV in ticks provides important information about the risk of incidental transmission to humans.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1089/vbz.2020.2720DOI Listing
February 2021

Metagenomic identification, sequencing, and genome analysis of porcine hepe-astroviruses (bastroviruses) in porcine feces in Japan.

Infect Genet Evol 2021 Mar 14;88:104664. Epub 2020 Dec 14.

Graduate School of Medicine and Veterinary Medicine, University of Miyazaki, Miyazaki, Japan; Department of Veterinary Science, Faculty of Agriculture, University of Miyazaki, Miyazaki, Japan; Center for Animal Disease Control, University of Miyazaki, Miyazaki, Japan. Electronic address:

Recently, hepe-astrovirus-like RNA viruses named bastroviruses (BastVs), have been found in human, pig, bat, and rat fecal samples. In this study, we determined nearly complete genome sequences of four BastVs in the feces of healthy pigs. Genetic characterization revealed that these porcine BastVs (PBastVs) and BastVs from other animals including humans, had the same genome organization, that is, they contained three predicted conserved domains of viral methyltransferase, RNA helicase, and RdRp in the nonstructural ORF1 and the astrovirus capsid domain in the structural ORF2. Phylogenetic analyses using RNA-dependent RNA polymerase and the capsid region revealed that PBastVs branched with bat and rat BastVs; however, the groups formed by each host were distantly related to human BastVs. Pairwise amino acid sequence comparison demonstrated that PBastVs shared 95.2-98.6% and 76.1-95.5% sequence identity among each other in the ORF1 and ORF2 regions, respectively; the sequence identities between PBastVs and BastVs from other animals were 21.4-42.5% and 9.1-20.6% in the ORF1 and ORF2 regions, respectively. This suggested that BastVs were derived from a common ancestor but evolved independently in each host population during a prolonged period. Putative recombination events were identified in the PBastV genome, suggesting that PBastVs gain sequence diversity and flexibility through recombination events. In an analysis of previously obtained metagenomic data, PBastV sequence reads were detected in 7.3% (23/315) of fecal samples from pigs indicating that PBastVs are distributed among pig populations in Japan.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.meegid.2020.104664DOI Listing
March 2021

Suppurative necrotizing bronchopneumonia caused by Nocardia cyriacigeorgica infection in a stranded striped dolphin (Stenella coeruleoalba) in Japan.

J Vet Med Sci 2021 Jan 11;83(1):146-150. Epub 2020 Dec 11.

Laboratory of Veterinary Pathology, Faculty of Agriculture, University of Miyazaki, Nishi 1-1, Gakuen-Kibana, Miyazaki 889-2192, Japan.

On a coastline in Miyazaki Prefecture, Japan, a wild subadult female striped dolphin was found dead. Necropsy revealed poor nutritional status and bilateral pneumonia, which was histologically diagnosed as severe suppurative necrotizing bronchopneumonia. Special staining detected numerous intralesional filamentous, branching bacteria, which was identified as Nocardia cyriacigeorgica by sequencing of 16S ribosomal RNA and gyrB genes. Other main histological findings included lymphoid depletion in the spleen and superficial cervical and pulmonary lymph nodes. Suppurative nocardiosis without a granulomatous reaction is uncommon, and it is assumed its pathogenesis was related to the host's immune status. This paper discusses the variable inflammatory response to nocardiosis and describes the first case of N. cyriacigeorgica infection in a wild striped dolphin in Japan.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1292/jvms.20-0234DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7870406PMC
January 2021

Direct Transmission of Severe Fever with Thrombocytopenia Syndrome Virus from Domestic Cat to Veterinary Personnel.

Emerg Infect Dis 2020 12;26(12):2994-2998

Two veterinary personnel in Japan were infected with severe fever with thrombocytopenia syndrome virus (SFTSV) while handling a sick cat. Whole-genome sequences of SFTSV isolated from the personnel and the cat were 100% identical. These results identified a nosocomial outbreak of SFTSV infection in an animal hospital without a tick as a vector.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3201/eid2612.191513DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7706950PMC
December 2020

Multiple genotypes of enterovirus G carrying a papain-like cysteine protease (PL-CP) sequence circulating on two pig farms in Japan: first identification of enterovirus G10 carrying a PL-CP sequence.

Arch Virol 2020 Dec 19;165(12):2909-2914. Epub 2020 Sep 19.

School of Veterinary Medicine, Azabu University, Sagamihara, Kanagawa, 252-5201, Japan.

Two and three genotypes of enterovirus G (EV-G) carrying a papain-like cysteine protease (PL-CP) sequence were detected on two pig farms and classified into genotypes G1 and G10, and G1, G8, and G17, respectively, based on VP1 sequences. A G10 EV-G virus bearing a PL-CP sequence was detected for the first time. Phylogenetic analysis of the P2 and P3 regions grouped the viruses by farm with high sequence similarity. Furthermore, clear recombination break points were detected in the 2A region, suggesting that PL-CP EV-G-containing strains gained sequence diversity through recombination events among the multiple circulating EV-G genotypes on the farms.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00705-020-04816-yDOI Listing
December 2020

Bovine Respiratory Syncytial Virus Enhances the Adherence of to Bovine Lower Respiratory Tract Epithelial Cells by Upregulating the Platelet-Activating Factor Receptor.

Front Microbiol 2020 31;11:1676. Epub 2020 Jul 31.

Graduate School of Medicine and Veterinary Medicine, University of Miyazaki, Miyazaki, Japan.

Coinfection by bovine respiratory syncytial virus (BRSV) and (PM) frequently has been observed in cattle that develop severe pneumonia. We recently reported that BRSV infection significantly increased PM adherence to bovine lower respiratory tract epithelial cells. However, the molecular mechanisms of enhanced PM adherence are not completely understood. To investigate whether BRSV infection regulates any cellular adherence receptors on bovine bronchus- and lung-epithelial cells, we performed proteomic and functional analyses. The proteomic analysis showed that BRSV infection increased the accumulation of the platelet-activating factor receptor (PAFR) in both cell types. Molecular experiments, including specific blockade, knockdown, and overexpression of PAFR, indicated that PM adherence to these cell types depended on PAFR expression. These findings highlight the role, in cattle with severe pneumonia, of the synergistic effect of coinfection by BRSV and PM in the lower respiratory tract.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fmicb.2020.01676DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7411089PMC
July 2020

Rapid inactivation of SARS-CoV-2 with deep-UV LED irradiation.

Emerg Microbes Infect 2020 Dec;9(1):1744-1747

Department of Hemovascular Medicine and Artificial Organs, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan.

The spread of novel coronavirus disease 2019 (COVID-19) infections worldwide has raised concerns about the prevention and control of SARS-CoV-2. Devices that rapidly inactivate viruses can reduce the chance of infection through aerosols and contact transmission. This study demonstrated that irradiation with a deep ultraviolet light-emitting diode (DUV-LED) of 280 ± 5 nm wavelength rapidly inactivates SARS-CoV-2 obtained from a COVID-19 patient. Development of devices equipped with DUV-LED is expected to prevent virus invasion through the air and after touching contaminated objects.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/22221751.2020.1796529DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7473214PMC
December 2020

Bovine Respiratory Syncytial Virus Decreased Pasteurella multocida Adherence by Downregulating the Expression of Intercellular Adhesion Molecule-1 on the Surface of Upper Respiratory Epithelial Cells.

Vet Microbiol 2020 Jul 2;246:108748. Epub 2020 Jun 2.

Graduate School of Medicine and Veterinary Medicine, University of Miyazaki, Miyazaki, Japan; Department of Veterinary Science, Faculty of Agriculture, University of Miyazaki, Miyazaki, Japan; Center for Animal Disease Control, University of Miyazaki, Miyazaki, Japan. Electronic address:

The synergistic infection of bovine respiratory syncytial virus (BRSV) and Pasteurella multocida (PM) may predispose cattle to develop severe pneumonia. Previously, we reported that BRSV infection significantly decreased PM adherence to the upper respiratory epithelial cells. It may allow bacteria to invade into the lower respiratory tract and lead to severe pneumonia. To investigate whether BRSV infection regulates the cell surface adherence receptor on bovine trachea epithelial cells (bTECs), we performed proteomic and functional analyses. BRSV infection decreased the expression of intercellular adhesion molecule-1 (ICAM1) on bTECs. Inhibition and knockdown experiments using anti-ICAM1 antibody and siRNAs targeting ICAM1 indicated that PM adherence to bTECs was dependent on ICAM1 expression. These data suggest that under normal conditions bTECs may capture PM in the upper respiratory tract, while BRSV infection reverses this mechanism. The proposed gateway function of bTECs is disrupted by BRSV infection that may facilitate bacterial invasion into the lower respiratory tract and lead to secondary or more severe respiratory infection.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.vetmic.2020.108748DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7265823PMC
July 2020

Genetic diversity of enterovirus G detected in faecal samples of wild boars in Japan: identification of novel genotypes carrying a papain-like cysteine protease sequence.

J Gen Virol 2020 08 16;101(8):840-852. Epub 2020 Jun 16.

Research and Education Center for Prevention of Global Infectious Diseases of Animals, Tokyo University of Agriculture and Technology, Fuchu, Tokyo 183-8509, Japan.

The genetic diversity of enterovirus G (EV-G) was investigated in the wild-boar population in Japan. EV-G-specific reverse transcription PCR demonstrated 30 (37.5 %) positives out of 80 faecal samples. Of these, viral protein 1 (VP1) fragments of 20 samples were classified into G1 (3 samples), G4 (1 sample), G6 (2 samples), G8 (4 samples), G11 (1 sample), G12 (7 samples), G14 (1 sample) and G17 (1 sample), among which 11 samples had a papain-like cysteine protease (PL-CP) sequence, believed to be the first discoveries in G1 (2 samples) or G17 (1 sample) wild-boar EV-Gs, and in G8 (2 samples) or G12 (6 samples) EV-Gs from any animals. Sequences of the non-structural protein regions were similar among EV-Gs possessing the PL-CP sequence (PL-CP EV-Gs) regardless of genotype or origin, suggesting the existence of a common ancestor for these strains. Interestingly, for the two G8 and two G12 samples, the genome sequences contained two versions, with or without the PL-CP sequence, together with the homologous 2C/PL-CP and PL-CP/3A junction sequences, which may explain how the recombination and deletion of the PL-CP sequences occured in the PL-CP EV-G genomes. These findings shed light on the genetic plasticity and evolution of EV-G.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1099/jgv.0.001446DOI Listing
August 2020

Molecular epidemiological survey and phylogenetic analysis of bovine respiratory coronavirus in Japan from 2016 to 2018.

J Vet Med Sci 2020 Jun 9;82(6):726-730. Epub 2020 Apr 9.

Center for Animal Disease Control, University of Miyazaki, Miyazaki 889-2192, Japan.

Bovine coronavirus (BCoV) is an etiological agent of bovine respiratory disease (BRD). BRD is a costly illness worldwide; thus, epidemiological surveys of BCoV are important. Here, we conducted a molecular epidemiological survey of BCoV in respiratory-diseased and healthy cattle in Japan from 2016 to 2018. We found that 21.2% (58/273) of the respiratory-diseased cattle were infected with BCoV. The respiratory-diseased cattle had virus amounts 4.7 times higher than those in the asymptomatic cattle. Phylogenetic analyses showed that the BCoV identified in Japan after 2005 formed an individual lineage that was distinct from the strains found in other countries. These results suggest that BCoV is epidemic and has evolved uniquely in Japan.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1292/jvms.19-0587DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7324836PMC
June 2020

Slaughterhouse survey for detection of bovine viral diarrhea infection among beef cattle in Kyushu, Japan.

J Vet Med Sci 2019 Oct 5;81(10):1450-1454. Epub 2019 Aug 5.

Department of Veterinary Science, Faculty of Agriculture, University of Miyazaki, Miyazaki 889-2192, Japan.

Bovine viral diarrhea virus (BVDV) footprint has spread across the globe and is responsible for one of the most economically important diseases in cattle. In Japan, some regional surveillance and preventive measures to control bovine viral diarrhea (BVD) have been implemented. However, BVDV infection is poorly understood in cattle industries, and there is no systematic BVD surveillance system and control program. Kyushu is the center for raising beef cattle in Japan. Therefore, this study aimed to determine the BVDV infection using a slaughterhouse survey among beef cattle in Kyushu, Japan. A total of 1,075 blood samples were collected at two regional slaughterhouses in Miyazaki prefecture from December 2015 to June 2016. Antigen ELISA was used for detection of BVDV antigen in blood samples. Two samples showed positive results (2/1,075; 0.18%). BVDV RNA was extracted from positive blood samples; the sequence was determined and analyzed by the neighbor-joining method for construction of the phylogenetic tree. Phylogenetic analysis based on the 5'-UTR revealed that the two positive samples were grouped into the same subtype BVDV-1b in the BVDV-1 genotype, but the infected cattle belonged to two different farms. In conclusion, this is the first study to identify the presence of BVDV in a slaughterhouse survey in Kyushu. These findings suggest that a slaughterhouse survey is a useful tool for developing a surveillance system for monitoring infectious diseases in cattle.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1292/jvms.19-0045DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6863731PMC
October 2019

Co-infection of epithelial cells established from the upper and lower bovine respiratory tract with bovine respiratory syncytial virus and bacteria.

Vet Microbiol 2019 Aug 12;235:80-85. Epub 2019 Jun 12.

Department of Veterinary Science, Faculty of Agriculture, University of Miyazaki, Miyazaki, Japan; Center for Animal Disease Control, University of Miyazaki, Miyazaki, Japan. Electronic address:

Bovine respiratory disease complex is a major disease affecting the global cattle industry. Multiple infections by viruses and bacteria increase disease severity. Previously, we reported that bovine respiratory syncytial virus (BRSV) infection increases adherence of Pasteurella multocida to human respiratory and bovine kidney epithelial cells. To examine the interaction between the virus and bacteria in bovine respiratory cells, we generated respiratory epithelial cell lines from bovine trachea (bTEC), bronchus (bBEC), and lung (bLEC). Although all established cell lines were infected by BRSV and P. multocida susceptibility differed according to site of origin. The cells derived from the lower respiratory tract (bBEC and bLEC) were significantly more susceptible to BRSV than those derived from the upper respiratory tract (bTEC). Pre-infection of bBEC and bLEC with BRSV increased adherence of P. multocida; this was not the case for bTEC. These results indicate that BRSV may reproduce better in the lower respiratory tract and encourage adherence of bacteria. Thus, we identify one possible mechanism underlying severe pneumonia.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.vetmic.2019.06.010DOI Listing
August 2019

Genotyping of swine Mycobacterium avium subsp. hominissuis isolates from Kyushu, Japan.

J Vet Med Sci 2019 Aug 3;81(8):1074-1079. Epub 2019 Jun 3.

Laboratory of Veterinary Microbiology, Department of Veterinary Science, Faculty of Agriculture, University of Miyazaki, 1-1 Gakuenkibanadai Nishi, Miyazaki, Miyazaki 889-2192, Japan.

The incidence of diseases caused by nontuberculous mycobacteria (NTM) is increasing annually worldwide, including Japan. Mycobacterium avium subsp. hoiminissuis (MAH) is one of the most common NTM species responsible for chronic lung diseases in animals and humans. In the current study, mycobacterial interspersed repetitive unit-variable number tandem repeat (MIRU-VNTR) typing was employed to characterize the genetic diversity of swine MAH isolates from Kyushu, Japan. In total, 309 isolates were obtained from the lymph nodes of 107 pigs not displaying any clinical signs of disease, of which 307 were identified as MAH, comprising 173 strains. Based on eight established MIRU-VNTR loci, the MAH strains represented 50 genotypes constituting three lineages, and 29 had not been described in the Mac French National Institute for Agricultural Research Nouzilly MIRU-VNTR (Mac-INMV) database. MAH was the dominant M. avium complex (MAC) in pigs from Kyushu, and there was high genetic diversity among genotype profiles of MAH from Kyushu. We identified three predominant genotype profiles in the tested area sharing high relatedness with genotype profiles of strains isolated in European countries. MAH was the most common NTM in pigs from Kyushu and exhibited high diversity, with new strain-derived genotypes.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1292/jvms.19-0048DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6715914PMC
August 2019

Mass spectrometry-based identification and whole-genome characterisation of the first pteropine orthoreovirus isolated from monkey faeces in Thailand.

BMC Microbiol 2018 10 17;18(1):135. Epub 2018 Oct 17.

Department of Microbiology and Immunology, Faculty of Tropical Medicine, Mahidol University, 420/6 Ratchawithi Road, Ratchathewi, Bangkok, 10400, Thailand.

Background: The pteropine orthoreovirus (PRV) was isolated from monkey (Macaca fascicularis) faecal samples collected from human-inhabited areas in Lopburi Province, Thailand. These samples were initially obtained to survey for the presence of hepatitis E virus (HEV).

Results: Two virus isolates were retrieved by virus culture of 55 monkey faecal samples. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was successfully used to identify the viruses as the segmented dsRNA orthoreovirus. Phylogenetic analysis of the Lopburi orthoreovirus whole-genomes revealed relationships with the well-characterised PRVs Pulau (segment L1), Cangyuan (segments L2, M3 and S3), Melaka (segments L3 and M2), Kampar (segments M1 and S2) and Sikamat (segments S1 and S4) of Southeast Asia and China with nucleotide sequence identities of 93.5-98.9%. RT-PCR showed that PRV was detected in 10.9% (6/55) and HEV was detected in 25.5% (14/55) of the monkey faecal samples.

Conclusions: PRV was isolated from monkey faeces for the first time in Thailand via viral culture and LC-MS/MS. The genetic diversity of the virus genome segments suggested a re-assortment within the PRV species group. The overall findings emphasise that monkey faeces can be sources of zoonotic viruses, including PRV and HEV, and suggest the need for active virus surveillance in areas of human and monkey co-habitation to prevent and control emerging zoonotic diseases in the future.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s12866-018-1302-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6192116PMC
October 2018

Detection of neutralizing antibody against porcine epidemic diarrhea virus in subclinically infected finishing pigs.

J Vet Med Sci 2018 Nov 2;80(11):1782-1786. Epub 2018 Oct 2.

Department of Veterinary Science, Faculty of Agriculture, University of Miyazaki, Miyazaki 889-2192, Japan.

The purpose of this study was to detect porcine epidemic diarrhea virus (PEDV) subclinically infected pigs shipped from non-case farms to slaughterhouses. Systematic sampling was conducted at two slaughterhouses. A total of 1,556 blood samples were collected from 80 case and non-case farms from pigs over 6 months old. Blood samples were centrifuged to obtain sera. Serial serum dilutions were subjected to serological examination for PEDV presence using Neutralization test (NT). The cut-off titer was set at titer of 1:2 dilution and farms with at least one positive sample in duplicate were classified as PED-positive farms. Several non-case farms (9.4%, 6/64) and 100% (16/16) of the case farms were indeed positive for PEDV. The proportion of seropositive animals from case farms was 63.7%, significantly different from that of non-case farms (4.3%, P<0.05). In both case and non-case farms, the proportion of seropositive animals in farrow-to-finish farms was significantly higher than in wean-to-finish farms (P<0.05). Seropositive animals in non-case farms were detected by NT in a sero-survey by sampling at slaughterhouses. Therefore, subclinically infected pigs should be considered prior to shipment.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1292/jvms.18-0132DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6261828PMC
November 2018

Bovine respiratory syncytial virus infection enhances Pasteurella multocida adherence on respiratory epithelial cells.

Vet Microbiol 2018 Jul 30;220:33-38. Epub 2018 Apr 30.

Department of Veterinary Science, Faculty of Agriculture, University of Miyazaki, Miyazaki, Japan; Center for Animal Disease Control, University of Miyazaki, Miyazaki, Japan. Electronic address:

Primary infection with bovine respiratory syncytial virus (BRSV) predisposes cattle to secondary infection with bacteria that cause bovine respiratory disease complex (BRDC). However, the interaction between BRSV and bacteria is unclear. This in vitro study examined the adherence of Pasteurella multocida (PM) to BRSV-infected cells was assessed in colony forming unit assays, by flow cytometry analysis, and by indirect immunofluorescence analysis (IFA) of epithelial cells (A549, HEp-2, and MDBK). An in vitro model based on infection of BRSV-infected epithelial cells revealed that PM adherence to BRSV-infected cells was 2- to 8-fold higher than uninfected cells. This was confirmed by flow cytometry analysis and IFA. Epithelial cell expression of mRNA encoding cytokines and chemokines increased after exposure to PM, but increased further after co-infection with BRSV and PM. BRSV-mediated adherence of PM to epithelial cells may underlie the serious symptoms of BRDC.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.vetmic.2018.04.031DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7117154PMC
July 2018

Development of pooled testing system for porcine epidemic diarrhoea using real-time fluorescent reverse-transcription loop-mediated isothermal amplification assay.

BMC Vet Res 2018 May 29;14(1):172. Epub 2018 May 29.

Animal Infectious Disease and Prevention, Department of Veterinary Sciences, Faculty of Agriculture, University of Miyazaki, Miyazaki, Japan.

Background: Porcine epidemic diarrhoea (PED) is an emerging disease in pigs that causes massive economic losses in the swine industry, with high mortality in suckling piglets. Early identification of PED virus (PEDV)-infected herd through surveillance or monitoring strategies is necessary for mass control of PED. However, a common working diagnosis system involves identifying PEDV-infected animals individually, which is a costly and time-consuming approach. Given the above information, the thrusts of this study were to develop a real-time fluorescent reverse transcription loop-mediated isothermal amplification (RtF-RT-LAMP) assay and establish a pooled testing system using faecal sample to identify PEDV-infected herd.

Results: In this study, we developed an accurate, rapid, cost-effective, and simple RtF- RT-LAMP assay for detecting the PEDV genome targeting M gene. The pooled testing system using the RtF-RT-LAMP assay was optimized such that a pool of at least 15 individual faecal samples could be analysed.

Conclusions: The developed RtF-RT-LAMP assay in our study could support the design and implementation of large-scaled epidemiological surveys as well as active surveillance and monitoring programs for effective control of PED.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s12917-018-1498-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5975689PMC
May 2018

Evaluation of an immunochromatography rapid diagnosis kit for detection of chikungunya virus antigen in India, a dengue-endemic country.

Virol J 2018 05 11;15(1):84. Epub 2018 May 11.

Vector Borne Disease Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, India.

Background: Chikungunya virus (CHIKV) and dengue virus (DENV) are arboviruses that share the same Aedes mosquito vector, and there is much overlap in endemic areas. In India, co-infection with both viruses is often reported. Clinical manifestations of Chikungunya fever is often confused with dengue fever because clinical symptoms of both infections are similar. It is, therefore, difficult to differentiate from those of other febrile illnesses, especially dengue fever. We previously developed a CHIKV antigen detection immunochromatography (IC) rapid diagnosis kit [1]. The current study examined the efficacy of previously mentioned IC kit in India, a dengue-endemic country.

Methods: Sera from 104 CHIKV-positive (by qRT-PCR) and/or IgM-positive (ELISA) subjects collected in 2016, were examined. Fifteen samples from individuals with CHIKV-negative/DENV-positive and 4 samples from healthy individuals were also examined. Of the 104 CHIKV-positive sera, 20 were co-infected with DENV.

Results: The sensitivity, specificity and overall agreement of the IC assay were 93.7, 95.5 and 94.3%, respectively, using qRT-PCR as a gold standard. Also, there was a strong, statistically significant positive correlation between the IC kit device score and the CHIKV RNA copy number. The IC kit detected CHIKV antigen even in DENV-co-infected patient sera and did not cross-react with DENV NS1-positive/CHIKV-negative samples.

Conclusions: The results suggest that the IC kit is useful for rapid diagnosis of CHIKV in endemic areas in which both CHIKV and DENV are circulating.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s12985-018-1000-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5948817PMC
May 2018

Dembo polymerase chain reaction technique for detection of bovine abortion, diarrhea, and respiratory disease complex infectious agents in potential vectors and reservoirs.

J Vet Sci 2018 May;19(3):350-357

Research and Education Center for Prevention of Global Infectious Diseases of Animals, Faculty of Agriculture, Tokyo University of Agriculture and Technology, Tokyo 183-0045, Japan.

Bovine abortion, diarrhea, and respiratory disease complexes, caused by infectious agents, result in high and significant economic losses for the cattle industry. These pathogens are likely transmitted by various vectors and reservoirs including insects, birds, and rodents. However, experimental data supporting this possibility are scarce. We collected 117 samples and screened them for 44 bovine abortive, diarrheal, and respiratory disease complex pathogens by using Dembo polymerase chain reaction (PCR), which is based on TaqMan real-time PCR. Fifty-seven samples were positive for at least one pathogen, including bovine viral diarrhea virus, bovine enterovirus, ser. Dublin, ser. Typhimurium, and ; some samples were positive for multiple pathogens. Bovine viral diarrhea virus and bovine enterovirus were the most frequently detected pathogens, especially in flies, suggesting an important role of flies in the transmission of these viruses. Additionally, we detected the genome from a cockroach sample for the first time. Our data suggest that insects (particularly flies), birds, and rodents are potential vectors and reservoirs of abortion, diarrhea, and respiratory infectious agents, and that they may transmit more than one pathogen at the same time.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.4142/jvs.2018.19.3.350DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5974516PMC
May 2018

Dengue Virus-Induced Reactive Oxygen Species Production in Rat Microglial Cells.

Jpn J Infect Dis 2017 07 22;70(4):383-387. Epub 2016 Dec 22.

Department of Medical Entomology, Faculty of Tropical Medicine, Mahidol University.

Encephalitis has been described worldwide as a severe complication in patients infected by dengue virus. Reactive oxygen species (ROS) production is a key mechanism involved in the neuronal damage caused by viral encephalitis. In the present study, the capability of dengue virus serotypes 2 (DENV2) and DENV4 to induce ROS production was investigated in a rat microglial cell line, HAPI cells. The cells were infected with DENV2 and DENV4 at a multiplicity of infection of 0.1 for a 2-h adsorption period. Japanese encephalitis virus (JEV) was used as the reference. DENV2- and DENV4-induced microglial activation and significantly increased ROS production corresponded to decreased cell viability. The activity of DENV4 was significantly higher than the activities of DENV2 and JEV at 48 and 72 h post infection. DENV4 partly induced ROS production via an iron-induced Fenton reaction, as demonstrated by the treatment with an iron chelator, deferiprone. Despite the induction of increased inducible nitric oxide synthase expression and nitric oxide (NO) production by JEV, DENV2, and DENV4 did not induce NO production, suggesting the activation of different pathways in response to infections by different viruses. In conclusion, DENV2 and DENV4 have the capability to induce ROS production and activate microglia, which have been reported as the key components of neuronal damage.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.7883/yoken.JJID.2016.236DOI Listing
July 2017

Use of Direct LAMP Screening of Broiler Fecal Samples for and in the Positive Flock Identification Strategy.

Front Microbiol 2016 30;7:1582. Epub 2016 Sep 30.

Department of Veterinary Sciences, Faculty of Agriculture, University of MiyazakiMiyazaki, Japan; Center for Animal Disease Control, University of MiyazakiMiyazaki, Japan.

Rapid identification of -positive flocks before slaughter, following freezing and heat treatment for the -positive carcasses at the slaughterhouses is an effective control strategy against foodborne campylobacteriosis. We evaluated a loop-mediated isothermal amplification (LAMP) assay for the direct screening of naturally contaminated chicken cloacal swabs for / to compare this assay with conventional quantitative culture methods. In a comparison study of 165 broilers, the LAMP assay showed 82.8% (48/58 by conventional culture) sensitivity, 100% (107/107) specificity, 100% (48/48) positive predictive value (PPV), and 91.5% (107/117) negative predictive value (NPV). In a comparison of 55 flocks, LAMP showed 90.5% (19/21) sensitivity, 100% (34/34) specificity, 100% (19/19) PPV, and 94.4% (34/36) NPV. In the cumulative total of 28 farm-level comparisons, LAMP showed 100% (12/12) sensitivity, 100% (16/16) specificity, 100% (12/12) PPV, and 100% (16/16) NPV. The LAMP assay required less than 90 min from the arrival of the fecal samples to final results in the laboratory. This suggests that the LAMP assay will facilitate the identification of /-positive broiler flocks at the farm level or in slaughterhouses before slaughtering, which would make it an effective tool in preventing the spread of contamination.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fmicb.2016.01582DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5043150PMC
September 2016

Dengue virus infection-enhancing antibody activities against Indonesian strains in inhabitants of central Thailand.

Microbes Infect 2016 Apr 1;18(4):277-84. Epub 2015 Dec 1.

BIKEN Endowed Department of Dengue Vaccine Development, Faculty of Tropical Medicine, Mahidol University, Bangkok 10400, Thailand; BIKEN Endowed Department of Dengue Vaccine Development, Research Institute for Microbial Diseases, Osaka University, Osaka 565-0871, Japan.

Dengue virus (DENV) infection-enhancing antibodies are a hypothetic factor to increase the dengue disease severity. In this study, we investigated the enhancing antibodies against Indonesian strains of DENV-1-4 in 50 healthy inhabitants of central Thailand (Bangkok and Uthai Thani). Indonesia and Thailand have seen the highest dengue incidence in Southeast Asia. The infection history of each subject was estimated by comparing his/her neutralizing antibody titers against prototype DENV-1-4 strains. To resolve the difficulty in obtaining foreign live viruses for use as assay antigens, we used a recombinant system to prepare single-round infectious dengue viral particles based on viral sequence information. Irrespective of the previously infecting serotype(s), most serum samples showed significantly higher enhancement titers against Indonesian DENV-2 strains than against Thai DENV-2 strains, whereas the opposite effect was observed for the DENV-3 strains. Equivalent enhancing activities were observed against both DENV-1 and DENV-4. These results suggest that the genotype has an impact on enhancing antibody activities against DENV-2 and DENV-3, because the predominant circulating genotypes of each serotype differ between Indonesia and Thailand.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.micinf.2015.11.002DOI Listing
April 2016

Detection of chikungunya virus antigen by a novel rapid immunochromatographic test.

J Clin Microbiol 2015 Feb 19;53(2):382-8. Epub 2014 Nov 19.

Department of Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan.

Chikungunya fever is a mosquito-borne disease of key public health importance in tropical and subtropical countries. Although severe joint pain is the most distinguishing feature of chikungunya fever, diagnosis remains difficult because the symptoms of chikungunya fever are shared by many pathogens, including dengue fever. The present study aimed to develop a new immunochromatographic diagnosis test for the detection of chikungunya virus antigen in serum. Mice were immunized with isolates from patients with Thai chikungunya fever, East/Central/South African genotype, to produce mouse monoclonal antibodies against chikungunya virus. Using these monoclonal antibodies, a new diagnostic test was developed and evaluated for the detection of chikungunya virus. The newly developed diagnostic test reacted with not only the East/Central/South African genotype but also with the Asian and West African genotypes of chikungunya virus. Testing of sera from patients suspected to have chikungunya fever in Thailand (n = 50), Laos (n = 54), Indonesia (n = 2), and Senegal (n = 6) revealed sensitivity, specificity, and real-time PCR (RT-PCR) agreement values of 89.4%, 94.4%, and 91.1%, respectively. In our study using serial samples, a new diagnostic test showed high agreement with the RT-PCR within the first 5 days after onset. A rapid diagnostic test was developed using mouse monoclonal antibodies that react with chikungunya virus envelope proteins. The diagnostic accuracy of our test is clinically acceptable for chikungunya fever in the acute phase.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1128/JCM.02033-14DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4298496PMC
February 2015

Chikungunya virus was isolated in Thailand, 2010.

Virus Genes 2014 Dec 12;49(3):485-9. Epub 2014 Aug 12.

Mahidol-Osaka Center for Infectious Diseases, Ratchathewi, Bangkok, 10400, Thailand.

Chikungunya fever (CHIKF) is an acute febrile illness caused by a mosquito-borne alphavirus, chikungunya virus (CHIKV). This disease re-emerged in Kenya in 2004, and spread to the countries in and around the Indian Ocean. The re-emerging epidemics rapidly spread to regions like India and Southeast Asia, and it was subsequently identified in Europe in 2007, probably as a result of importation of chikungunya cases. On the one hand, chikungunya is one of the neglected diseases and has only attracted strong attention during large outbreaks. In 2008-2009, there was a major outbreak of chikungunya fever in Thailand, resulting in the highest number of infections in any country in the region. However, no update of CHIKV circulating in Thailand has been published since 2009. In this study, we examined the viral growth kinetics and sequences of the structural genes derived from CHIKV clinical isolates obtained from the serum specimens of CHIKF-suspected patients in Central Thailand in 2010. We identified the CHIKV harboring two mutations E1-A226V and E2-I211T, indicating that the East, Central, and South African lineage of CHIKV was continuously circulating as an indigenous population in Thailand.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s11262-014-1105-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4232745PMC
December 2014