Consulta: creatorFacets:"横山, 直明"
Registros recuperados: 39
Data/hora: 07/06/2024 15:08:15

Adjuvant Effect of Oligomannose-Coated Liposome-Based Platform for veccine against African Trypanosomosis
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: Kuboki, Noritaka; Yokoyama, Naoaki; Namangala, B; Okamura, Masashi; Inoue, Noboru; Takagi, Hideaki; Nakayama, Tomoko; Nishikawa, Yoshifumi; Ikehara, Yuzuru; Kojima, Naoya; 横山, 直明; 井上, 昇; 西川, 義文.
Palavras-chave: Adjuvant; African trypanosome; Immunization; Oligomannose-coated liposome(OML).
Ano: 2008
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2222

The Babesia bovis BvP36 gene is expressed at least in the asexual stage of Babesia merozoite
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: Khukhuu, A; Sivakumar, T; Alhassan, A; Ota, N; Yokoyama, N; Igarashi, I; 横山, 直明; 五十嵐, 郁男.
Recently, Babesia bovis genome project identified a novel gene, which is homologous to the gene encoding sporozoite P36 antigen in Plasmodium parasites. In the present study, we isolated the P36 homologous gene from the genomic DNA of B. bovis and designated it as the BvP36 gene. The sequence of the BvP36 gene was identical to that reported previously. This gene was expressed in an Escherichia coli system to produce a recombinant protein (rBvP36). The rBvP36 protein was produced as a highly soluble form in E. coli and was detected by western blot analyses of sera collected from cattle experimentally infected with B. bovis and B. bigemina merozoites. In indirect immunofluorescence tests, sera collected from mice immunized with rBvP36 showed strong reactions...
Ano: 2009
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2385

A Clinical Case of Severe Anemia in a Sheep Coinfected with Mycoplasma ovis and 'Candidatus Mycoplasma haemovis' in Hokkaido, Japan
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: TAGAWA, Michihito; TAKEUCHI, Toshihiko; FUJISAWA, Tetsuro; KONNO, Yasuhiro; YAMAMOTO, Shinji; MATSUMOTO, Kotaro; YOKOYAMA, Naoaki; INOKUMA, Hisashi; 松本, 高太郎; 横山, 直明; 猪熊, 壽.
A 2-year-old East Friesian sheep imported from Australia exhibited severe anemia after contagious pustular dermatitis in Hokkaido, Japan. Hemoplasma infection was confirmed in blood smears. Both Mycoplasma ovis and ‘Candidatus Mycoplasma haemovis’ were detected by PCR and sequence analyses. In the epidemiological analysis, dual pathogens were detected in 6 of 12 (50.0%) sheep imported from Australia with the infected ewe at the same time, 1 of 5 (20.0%) sheep introduced from a domestic farm in Hokkaido, and in 1 of 16 (6.3%) sheep from an epidemiologically unrelated ranch. It is the first clinical case of sheep to confirm coinfection of these pathogens in Japan.
Palavras-chave: 'Candidatus Mycoplasma haemovis'; Case report; Japan; Mycoplasma ovis; Sheep.
Ano: 2012
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/3582

TRANSIENT EXPRESSION OF A GREEN FLUORESCENT PROTEIN GENE IN BABESIA BOVIS
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: Fujii, Kei; Yokoyama, Naoaki; Takabatake, Noriyuki; Suzuki, Hiroshi; Xuan, Xuenan; Igarashi, Ikuo; 横山, 直明; 鈴木, 宏志; 玄, 学南; 五十嵐, 郁男.
In hemoprotozoa，gene transfer technology provides an important tool to aid in the functional study of parasite genes. In this study，a transfer vector containing the enhanced green fluorescent protein (EGFP) gene laid between the Toxoplasma gondii GRAI promoter region and the GRA2 polyA signal region was constructed and transfected into the in vitro culture of Babesia boνis by the electroporation method.On the first and second days post-transfection，clear positive fluorescences were detected in some parasite bodies， indicating the successful expression of the EGFP gene controlled by the GRA-1 promoter in B. bovis. However， the positive parasites were not ubiquitous and finally disappeared until the forth day post-transfection. This is the first time that...
Ano: 2003
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/631

IN VITRO GROWTH INHIBITORY EFFECTS OF COMBINED APPLICATIONS OF CLOTRIMAZOLE, KETOCONAZOLE, AND CLODINAFOP-PROPARGYL ON EQUINE BABESIA PARASITES
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: Bork, Sabine; Yokoyama, Naoaki; Okamura, Masashi; Igarashi, Ikuo; 横山, 直明; 五十嵐, 郁男.
Recently，we reported the in vitro growth inhibitory effects of the imidazole derivatives，clotrimazole(CLT) and ketoconazole (KC)，and the herbicide，clodinafop-propargyl(CP)，against bovine and equine Babesia parasites. Additionally，in the bovine species，several combined applications of the CLT，KC，and CP were reported to significantly increase the inhibitory effects. In this study，similar combination tests were carried out in order to confirm possible synergistic effects in the equine species，Babesia caballi and Babesia equi. Combinations of CLT/KC， CLT/CP，and CLT/KC/CP exerted a significantly enhanced growth inhibitory efficacy in B. caballi，in contrast to B. equi，where no synergistic effects were observed in any of the combinations. Our results suggest that...
Palavras-chave: In vitro; Babesia; Clotrimazole; Ketoconazole; Clodinafop-propargyl.
Ano: 2003
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/637

Dual Presence of Anaplasma phagocytophilum and Its Closely Related Anaplasma sp. in Ixodid Ticks in Hokkaido, Japan, and Their Specific Molecular Detection
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: YBAÑEZ, Adrian Patalinghug; MATSUMOTO, Kotaro; KISHIMOTO, Toshio; YOKOYAMA, Naoaki; INOKUMA, Hisashi; 松本, 高太郎; 横山, 直明; 猪熊, 壽.
Anaplasma phagocytophilum causes human granulocytic anaplasmosis (HGA) and tick-borne fever in ruminants. A closely related and potentially novel Anaplasma sp. in Japan was recently characterized. The aims of the study were to provide molecular evidence for the presence of these 2 species in Japan, and to develop a reliable PCR method based on the nucleotide differences within the citrate synthase (gltA) gene. DNA samples from 182 ixodid ticks (134 Ixodes persulcatus, 35 Haemaphysalis douglasii and 13 I. ovatus) collected from 2 sites in Hokkaido, Japan, were screened for A. phagocytophilum and its closely related Anaplasma sp. (herein designated as Anaplasma sp. Japan) using 16S rRNA PCR, revealing a combined prevalence rate of 27.5% (50 samples). The...
Palavras-chave: 16S rRNA; Anaplasma phagocytophilum; Anaplasma sp.; GltA; GroEL.
Ano: 2012
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/3839

Molecular Prevalence of Different Genotypes of Theileria orientalis Detected from Cattle and Water Buffaloes In Thailand
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: Altangerel, Khukhuu; Sivakumar, Thillaiampalam; Inpankaew, Tawin; Jittapalapong, Sathaporn; Terkawi, Mohamad Alaa; Ueno, Akio; Xuan, Xuenan; Igarashi, Ikuo; Yokoyama, Naoaki; 玄, 学南; 五十嵐, 郁男; 横山, 直明.
Here we report on an epidemiological study regarding the molecular prevalence of different genotypes of Theileria orientalis present among domestic cattle and water buffalo populations bred in Thailand. A phylogenetic analysis based on the parasitic gene encoding a major piroplasm surface protein revealed the presence of 5 genotypes (Types 1, 3, 5, 7, and N-3) in cattle and 7 genotypes (Types 1, 3, 4, 5, 7, N-2, and N-3) in water buffaloes. Types 4, 7, and N-3 of T. orientalis were reported for the first time in water buffaloes. The previously reported C and Thai types from Thailand clustered as types 7 and 6, respectively, in the present analysis. Great similarities were observed among nucleotide sequences of isolates of the same genotype from cattle and...
Ano: 2011
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/3592

The Genetic Diversity of Merozoite Surface Antigen 1 (MSA-1) among Babesia bovis Detected from Cattle Populations in Thailand, Brazil and Ghana
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: NAGANO, Daisuke; SIVAKUMAR, Thillaiampalam; DE DE MACEDO, Alane Caine Costa; INPANKAEW, Tawin; ALHASSAN, Andy; IGARASHI, Ikuo; YOKOYAMA, Naoaki; 五十嵐, 郁男; 横山, 直明.
In the present study, we screened blood DNA samples obtained from cattle bred in Brazil (n=164) and Ghana (n=80) for Babesia bovis using a diagnostic PCR assay and found prevalences of 14.6% and 46.3%, respectively. Subsequently, the genetic diversity of B. bovis in Thailand, Brazil and Ghana was analyzed, based on the DNA sequence of merozoite surface antigen-1 (MSA-1). In Thailand, MSA-1 sequences were relatively conserved and found in a single clade of the phylogram, while Brazilian MSA-1 sequences showed high genetic diversity and were dispersed across three different clades. In contrast, the sequences from Ghanaian samples were detected in two different clades, one of which contained only a single Ghanaian sequence. The identities among the MSA-1...
Palavras-chave: Babesia bovis; Brazil; Ghana; MSA-1; Thailand.
Ano: 2013
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/4014

原虫病診断技術の開発
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: 五十嵐, 郁男; 横山, 直明; 井上, 昇; 玄, 学南.
発行年は推定
Ano: 2007
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/3515

Prevalence and Risk Factor Analysis of Bovine Hemoplasma Infection by Direct PCR in Eastern Hokkaido, Japan
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: TAGAWA, Michihito; YBANEZ, Adrian P.; MATSUMOTO, Kotaro; YOKOYAMA, Naoaki; INOKUMA, Hisashi; 松本, 高太郎; 横山, 直明; 猪熊, 壽.
The prevalence and risk factors of 2 bovine hemoplasma species—Mycoplasma wenyonii (Mw) and “Candidatus Mycoplasma haemobos” (CMh)—were examined by direct PCR using whole blood samples collected from 343 cattle in Eastern Hokkaido, Japan. The sensitivity of the direct PCR assay was 10-fold higher than the standard PCR assay, detecting 5 copies of bovine hemoplasma DNA per reaction. An epidemiological survey of sampling location, living conditions, age and bovine leukemia virus antibody was performed to assess infection risk factors. The prevalence rates were 38.5% for Mw and 39.1% for CMh, respectively, with an overall prevalence rate of 64.7% for all bovine hemoplasma infections. Significant differences were found in sampling location, living conditions...
Palavras-chave: Bovine hemoplasma; Direct PCR; Japan; Risk factor.
Ano: 2012
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/3838

In vitro inhibitory effect of fosmidomycin on the asexual growth of Babesia bovis and Babesia bigemina
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: Sivakumar, T; Aboulaila, M. R. A.; Khukhuu, A; Iseki, H; Alhassan, A; Yokoyama, Naoaki; Igarashi, Ikuo; 横山, 直明; 五十嵐, 郁男.
The in vitro inhibitory effect of fosmidomycin was evaluated against the asexual growth of bovine Babesia parasites (Babesia bovis and Babesia bigemina). In the cultures with these parasites, severe reduction of parasite growth was observed by the addition of 1.25 μg/ml of the final drug concentration. Under these conditions, B. bigemina was completely cleared until the third day of cultivation. On the other hand, B. bovis was completely eliminated on the fourth day when the concentration was 6.25 μg/ml in the culture. These parasites failed to grow again when a drug-free medium was substituted for the subsequent cultivation. The IC50 values of fosmidomycin against B. bovis were determined as 0.88 and 0.63 μg/ml in the in vitro cultures with...
Palavras-chave: Fosmidomycin; Babesia bovis; Babesia bigemina; Asexual growth; In vitro culture.
Ano: 2008
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2235

北海道東部の放牧場における小型ピロプラズマ感染リスク低減要因の検討
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: 猪熊, 壽; 横山, 直明; INOKUMA, Hisashi; YOKOYAMA, Naoaki.
北海道東部(道東)の放牧地における牛の小型ピロプラズマ感染りスク低減要因について調査した。道東ではシュルツェマダニ，ヤマトマダニ，ダグラスチマダニが採取され， PCRにより小型ピロプラズマ遺伝子断片が検出され，これらのマダニがベクターとなりうる可能性が考えられた。エゾシカからは多数のマダニが回収され，小型ピロプラズマのベクターを牛の放牧地内へ持ち込むという意味で小型ピロプラズマ感染リスクに関わる動物と考えられた。また，放牧管理体制との関連では，野生動物侵入防止柵の設置，あるいは牧柵周辺の下草刈りが小型ピロプラズマ感染リスク低減に有効である可能性が考えられた。 Factors to decrease risk for Theileria orientalis infection of cattle in pastureland in Eastern Hokkaido were investigated. Ixodes persulcatus，Ixodes ovatus and Haemaphysalis douglusii were collected from the vegetation of the pastureland，and DNA　fragments of T. orientalis were detected from these ticks by using PCR. The results suggested that these tick species may be vectors for T. orientalis in this area. Many ticks have been recovered from wild sika deer，and it was thought...
Palavras-chave: 道東; リスク低減要因; Theileria orientalis; Eastern Hokkaido; Factors to decrease risk.
Ano: 2010
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2790

Prevalence of the enteric parasites of ducks from Behera governorate, Egypt
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: AbouLaila, M; El-Bahy, N; Hilali, M; Yokoyama, N; Igarashi, I; 横山, 直明; 五十嵐, 郁男.
This study of enteric parasites of ducks was undertaken to determine their prevalence and the relationships between their prevalence and the age and breed of ducks in the Behera governorate, Egypt. A total of 110 ducks of different ages and breeds were examined. The prevalence of helminths was 4.54% from which the prevalence of nematode, cestode, and trematode infections was 2.72%, 3.63%, and 1.81%, respectively. The recovered nematodes were Ascaridia galli (0.9%) and Heterakis gallinarum (1.81%). The reported trematodes were Echinoparyphium recurvatum (0.9%) and Echinoparyphium paraulum (1.81%). The new reported cestodes were Cladogynia phoeniconaiadis (3.63%), Echinolepis carioca (3.63%), and Baerfainia anoplocephaloides (3.63%). The helminths infections...
Palavras-chave: Ducks; Enteric parasites; Egypt.
Ano: 2011
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/3125

CLONING AND EXPRESSION OF AN ANTIGEN OF BABESIA GIBSONI IN ESCHERICHIA COLI AND ITS USE FOR THE IMMUNODIAGNOSIS OF CANINE BABESIOSIS
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: Fukumoto, Shinya; Sekine, Yukiko; Kimbita, Elikira; Huang, Xiaohong; Xuan, Xuenan; Inoue, Noboru; Yokoyama, Naoaki; Igarashi, Ikuo; Fujisaki, Kozo; Sugimoto, Chihiro; Nagasawa, Hideyuki; Mikami, Takeshi; Suzuki, Hiroshi; 福本, 晋也; 玄, 学南; 井上, 昇; 横山, 直明; 五十嵐, 郁男; 鈴木, 宏志.
Palavras-chave: Babesia gibsoni; Babesia canis; CDNA library; ELISA; P30 gene.
Ano: 2002
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/624

オリゴマンノース糖鎖被覆(OML)リポソームワクチン投与後の牛の免疫応答の解析
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: 横山, 直明; Yokoyama, Naoaki.
Ano: 2008
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2184

IMMUNOSCREENING OF BABESIA RODHAINI GENES ENCODING IMMUNOGENIC PROTEINS FROM THE CDNA EXPRESSION PHAGE LIBRARY
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: Fujii, Kei; Takabatake, Noriyuki; Boonchit, Suthisak; Hirata, Haruyuki; Yokoyama, Naoaki; Igarashi, Ikuo; 横山, 直明; 五十嵐, 郁男.
Palavras-chave: Babesia rodhaini; Babesiosis; Immunoscreening; CDNA expression library.
Ano: 2002
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/626

Phylogenetic analysis of Theileria orientalis in cattle bred in Fujian province，China
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: Sivakumar, T; Khukhuu, A; Igarashi, I; Xuan, X; Guo, G; Huang, X; Yokoyama, N; 五十嵐, 郁男; 玄, 学南; 横山, 直明.
A molecular epidemiological survey on Theileria orientalis was conducted in a cattle population of Fujian province in China. The screening polymerase chain reaction assay showed that 23 (45%) of 51 blood samples were positive for T. orientalis. DNA sequencing of the major piroplasm surface antigen-encoding gene indicated the presence of 3 different genotypes in the study area(types 1，2，and 5) and identified T. orientalis types 1 and 2 as the major genotypes in the sample population.  Because type 2 (Ikeda type in Japan) has been recognized as a relatively virulent genotype of T. orientalis，control and preventive measures to minimize the incidence of infectious diseases among cattle bred in China are necessary.
Palavras-chave: Theileria orientalis; Cattle; China; Epidemiology; Genotype.
Ano: 2011
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/3098

Molecular Epidemiological Survey of Theileria orientalis in Thua Thien Hue Province, Vietnam
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: KHUKHUU, Altangerel; LAN, Dinh Thi Bich; LONG, Phung Thang; UENO, Akio; LI, Yan; LUO, Yuzi; MACEDO, Alan Caine Costa de; MATSUMOTO, Kotaro; INOKUMA, Hisashi; KAWAZU, Shin-Ichiro; IGARASHI, Ikuo; XUAN, Xuenan; YOKOYAMA, Naoaki; 松本, 高太郎; 猪熊, 壽; 河津, 信一郎; 五十嵐, 郁男; 玄, 学南; 横山, 直明.
Theileria orientalis is a benign bovine protozoan parasite that occasionally causes serious economic loss in the livestock industry. We report the findings of a molecular epidemiological survey of T. orientalis in 94 Vietnamese yellow cattle, 43 water buffaloes, 21 sheep, 21 goats and 85 blood-sucking ticks of cattle in the Thua Thien Hue province of Vietnam. The major piroplasm surface protein (MPSP) gene of T. orientalis was detected using polymerase chain reaction from 13 cattle (13.8%), 11 water buffaloes (25.6%), 1 sheep (4.8%) and 9 ticks (10.6%). Phylogenetic analysis using MPSP gene sequences showed the presence of seven genotypes, four previously categorized genotypes (Types 1, 3, 5 and 7) and three new genotypes (Types N-1, N-2 and N-3).
Palavras-chave: Cattle; Genotype; MPSP; Theileria orientalis; Vietnam.
Ano: 2011
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/3585

Evaluation of inhibitory effect of methylene blue against Babesia and Theileria parasites
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: Tuvshintulga, B.; Sivakumar, T.; Salama, A.A.; Yokoyama, N.; Igarashi, I; 五十嵐, 郁男; 横山, 直明.
Methylene blue, the first fully synthetic drug, has been widely used in medical treatments. A few decades ago, this drug was used as an antimalarial agent. In this study, the in vitro inhibitory effect of methylene blue on Babesia bovis, B. bigemina, B. caballi, and Theileria equi (B. equi) and the in vivo inhibitory effect on B. microti were evaluated. Methylene blue significantly inhibited the growth of B. bovis, B. caballi, and T. equi at a 0.1 μM concentration, while B. bigemina was significantly inhibited at 0.01 μM, on day 3 of cultivation. The half maximal inhibitory concentrations (IC50) of methylene blue against B. bovis, B. bigemina, B. caballi, and T. equi were calculated as 0.83±0.02, 0.68±0.09, 0.54±0.14, and 0.49±0.06 μM, respectively. The...
Palavras-chave: Methylene blue; Babesia; Theileria; In vitro; In vivo.
Ano: 2015
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/4242

Inhibitory effect of apicidin on in vitro and in vivo growth of Babesia parasites
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: Munkhjargal, T; Aboulaila, M.R.A; Sivakumar, T; Yokoyama, N; Igarashi, I; 横山, 直明; 五十嵐, 郁男.
Apicidin, a histone deacetylase inhibitor, has a broad spectrum of anti-protozoal activities against apicomplexan parasites. In the present study, we evaluated the inhibitory effect of apicidin on the asexual growth of bovine Babesia parasites (B. bovis and B. bigemina) in vitro, as well as on the in vivo growth of B. microti in mice. The growth of B. bovis and B. bigemina was significantly inhibited in the presence of 3 ng/ml apicidin. Complete inhibition of B. bovis and B. bigemina growth was achieved on the fourth and third days, respectively, after treatment with 729 ng/ml apicidin. These parasites failed to grow again even when drug-free medium was substituted. The 50% inhibitory concentrations of apicidin against B. bovis and B. bigemina were...
Palavras-chave: Apicidin; B .bovis; B .bigemina; B. microti; Asexual growth.
Ano: 2009
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2386

原虫・宿主相互細胞機能の免疫病理学的研究
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: 横山, 直明; 五十嵐, 郁男; Yokoyama, Naoaki; Igarashi, Ikuo.
発行年は推定
Ano: 2007
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/3506

Specific Molecular Detection of Anaplasma sp. Closely Related to Anaplasma phagocytophilum in Ixodid Ticks and Cattle in a Pastureland in Hokkaido, Japan
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: Ybañez, Adrian P.; Tagawa, Michihito; Matsumoto, Kotaro; Kishimoto, Toshio; Yokoyama, Naoaki; Inokuma, Hisashi; 横山, 直明; 猪熊, 壽.
http://online.liebertpub.com/doi/abs/10.1089/vbz.2012.0963
Palavras-chave: Anaplasma sp.; Anaplasma phagocytophilum; Heat-shock operon; Ticks; Cattle.
Ano: 2013
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/3834

First detection of Babesia venatorum (EU1) in Ixodes persulcatus ticks in Mongolia
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: Tuvshintulga, B.; Battsetseg, B.; Battur, B.; Myagmarsuren, P.; Narantsatsral, S.; Sivakumar, T.; Takemae, H.; Igarashi, I.; Inoue, N.; Yokoyama, N.; 五十嵐, 郁男; 井上, 昇; 横山, 直明.
Babesia venatorum, formerly known as Babesia sp. EU1, is a zoonotic hemoprotozoan parasites that commonly infects deer. In the present study, we investigated B. venatorum infection in Ixodes persulcatus, an important tick vector capable of transmitting several tick-borne pathogens that cause babesiosis, encephalitis, tularemia, and Lyme diseases. DNA samples extracted from questing I. persulcatus ticks (n=63) that had been collected in Selenge province of Mongolia in 2012 and 2013 were screened for B. venatorum using a nested PCR assay. The findings showed that two of 63 DNA samples were positive for B. venatorum. The 18S rRNA sequences amplified from B. venatorum-positive DNA samples shared high identity scores (96.1–99.9%) with known B. venatorum...
Palavras-chave: Babesia venatorum; 18S rRNA; Ixodes persulcatus; Mongolia.
Ano: 2015
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/4243

FUCOIDAN INHIBITS THE IN VITRO GROWTH OF BABESIA BOVIS
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: Takabatake, Noriyuki; Hashiba, Shintaro; Bork, Sabine; Okamura, Masashi; Yokoyama, Naoaki; Igarashi, Ikuo; 横山, 直明; 五十嵐, 郁男.
Palavras-chave: Babesia bovis; Fucoidan.
Ano: 2004
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/646

CURRENT SERODIAGNOSTIC MEASURES FOR EQUINE BABESIOSIS
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: Hirata, Haruyuki; Yokoyama, Naoaki; Xuan, Xuenan; Igarashi, Ikuo; 横山, 直明; 玄, 学南; 五十嵐, 郁男.
Palavras-chave: Babesia equi; Babesia caballi; Diagnosis; ELISA; ICT.
Ano: 2004
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/638

Calcium ions are involved in egress of Babesia bovis merozoites from bovine erythrocytes
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: MOSSAAD, Ehab; ASADA, Masahito; NAKATANI, Daichi; INOUE, Noboru; YOKOYAMA1), Naoaki; KANEKO, Osamu; KAWAZU, Shin-ichiro; 井上, 昇; 横山, 直明; 河津, 信一郎.
Bovine babesiosis is a livestock disease known to cause economic losses in endemic areas. The apicomplexan parasite Babesia bovis is able to invade and destroy the host’s erythrocytes leading to the serious pathologies of the disease, such as anemia and hemoglobinuria. Understanding the egress mechanisms of this parasite is therefore a key step to develop new therapeutic strategies. In this study, the possible involvement of Ca2+ in the egress of B. bovis merozoites from infected erythrocytes was investigated. Egress was artificially induced in vitro using calcium ionophore A23187 and thapsigargin to increase Ca2+ concentration in the cytosol of the parasite cells. The increased intracellular Ca2+ concentration following these treatments was confirmed...
Palavras-chave: Babesia bovis; Calcium ionophore; Calcium signalling; Egress.
Ano: 2015
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/4071

Prevalence and Molecular Analyses of Hemotrophic Mycoplasma spp. (Hemoplasmas) Detected in Sika Deer (Cervus nippon yesoensis) in Japan
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: TAGAWA, Michihito; MATSUMOTO, Kotaro; YOKOYAMA, Naoaki; INOKUMA, Hisashi; 松本, 高太郎; 横山, 直明; 猪熊, 壽.
Hemotropic mycoplasmas (hemoplasmas) are cell-wall deficient, epierythrocytic bacteria that cause infectious anemia in several mammalian species. The prevalence of hemoplasma species was examined by screening and species-specific PCR using blood samples collected from 51 sika deer in Hokkaido, Japan. Molecular analyses were performed for the 16S rRNA, 23S rRNA and RNase P RNA (rnpB) gene sequences. A total of 23/51 (45%) deer DNA samples were positive for hemoplasmas in the screening PCR. Using species-specific PCR, 12 and 17 samples were positive for ‘Candidatus Mycoplasma haemocervae’ and ‘Candidatus M. erythrocervae’, respectively. Sequencing and phylogenetic trees of those three genes indicate that the ‘Candidatus M. haemocervae’ and ‘Candidatus M....
Palavras-chave: Cervus nippon yesoensis; Hemoplasma; Japan; Phylogeny.
Ano: 2014
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/4012

PCR Detection and Genetic Diversity of Bovine Hemoprotozoan Parasites in Vietnam
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: SIVAKUMAR, Thillaiampalam; LAN, Dinh Thi Bich; LONG, Phung Thang; YOSHINARI, Takeshi; TATTIYAPONG, Muncharee; GUSWANTO, Azirwan; OKUBO, Kazuhiro; IGARASHI, Ikuo; INOUE, Noboru; XUAN, Xuenan; YOKOYAMA, Naoaki; 井上, 昇; 玄, 学南; 横山, 直明.
Hemoprotozoan infections often cause serious production losses in livestock. In the present study, we conducted a PCR-based survey of Babesia bovis, Babesia bigemina, Theileria annulata, Theileria orientalis, Trypanosoma evansi and Trypanosoma theileri, using 423 DNA samples extracted from blood samples of cattle (n=202), water buffaloes (n=43), sheep (n=51) and goats (n=127) bred in the Hue and Hanoi provinces of Vietnam. With the exception of T. annulata and T. evansi, all other parasite species (B. bovis, B. bigemina, T. orientalis and T. theileri) were detected in the cattle populations with B. bovis being the most common among them. Additionally, four water buffaloes and a single goat were infected with B. bovis and B. bigemina, respectively. The Hue...
Palavras-chave: Epidemiology; Hemoprotozoa; Livestock; PCR; Vietnam.
Ano: 2013
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/4015

Specific Molecular Detection and Characterization of Anaplasma marginale in Mongolian Cattle
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: YBAÑEZ, Adrian Patalinghug; SIVAKUMAR, Thillaiampalam; BATTSETSEG, Badgar; BATTUR, Banzragch; ALTANGEREL, Khukhuu; MATSUMOTO, Kotaro; YOKOYAMA, Naoaki; INOKUMA, Hisashi; 松本, 高太郎; 横山, 直明; 猪熊, 壽.
Anaplasma marginale is an etiologic agent of bovine anaplasmosis. This study aimed to molecularly detect and characterize A. marginale that is prevalent in Mongolian cattle populations. A highly specific and sensitive nested PCR (nPCR) method based on the Msp5 gene was developed to detect A. marginale (Msp5 nPCR). The method detected A. marginale from the positive DNA samples obtained from different countries, while no amplicons were observed from DNA samples of several other bovine blood pathogens tested. The detection limit of Msp5 nPCR was determined to be 2 copies/μl. The method was tested against field blood DNA samples prepared from 300 Mongolian cattle in 2010. Results indicated a prevalence rate of 8.7% (26 of 300). On the other hand, partial DNA...
Palavras-chave: Anaplasma marginale; Cattle; Mongolia; Msp5; PCR.
Ano: 2013
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/3867

Involvement of a Host Erythrocyte Sialic Acid Content in Babesia bovis Infection
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: TAKABATAKE, Noriyuki; OKAMURA, Masashi; YOKOYAMA, Naoaki; OKUBO, Kazuhiro; IKEHARA, Yuzuru; IGARASHI, Ikuo; 横山, 直明; 五十嵐, 郁男.
Host sialic acid (SA) has recently been suggested to play an important role in erythrocyte (RBC) infection by Babesia spp. The present study attempted to further determine the specific type of SAs important in the RBC invasion. Bovine RBC was found to bear abundant α2-3-linked SA residues but not α2-6-linked SA in nature, confirmed by flow cytometric analysis of the neuraminidase (Nm)-treated RBCs. Lectin-blot analyses revealed the removal of α2-3-linked SAs from the 97-, 33-, and 31-kDa bands by the Nm treatment. Addition of the Nm-treated RBCs into an in vitro culture of B. bovis resulted in a decreased population of the parasitized RBCs. The thin smear samples from the cultures were then observed under a confocal laser scanning microscope after staining...
Palavras-chave: Babesia bovis; Erythrocyte; Invasion; Sialic acid.
Ano: 2007
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/4166

First Molecular Characterization of Anaplasma marginale in Cattle and Rhipicephalus (Boophilus) microplus Ticks in Cebu, Philippines
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: YBAÑEZ, Adrian Patalinghug; SIVAKUMAR, Thillaiampalam; YBAÑEZ, Rochelle Haidee Daclan; RATILLA, Jowarren Catingan; PEREZ, Zandro Obligado; GABOTERO, Shirleny Reyes; HAKIMI, Hassan; KAWAZU, Shin-ichiro; MATSUMOTO, Kotaro; YOKOYAMA, Naoaki; INOKUMA, Hisashi; 河津, 信一郎; 松本, 高太郎; 横山, 直明; 猪熊, 壽.
Anaplasma marginale has been detected in the Philippines only by peripheral blood smear examination and serological methods. This study generally aimed to molecularly detect and characterize A. marginale in cattle and ticks in Cebu, Philippines. A total of 12 bovine blood samples and 60 Rhipicephalus (Boophilus) microplus ticks were collected on the Cebu Island in 2011. 16S rRNA-based screening-PCR and DNA sequencing revealed 8 cattle (66.7%) and 8 ticks (13.3%) to be positive for A. marginale, and 1 tick (1.7%) to be positive for A. centrale. Selected positive DNA samples were further characterized based on 16S rRNA (longer sequence), Msp5, Msp1α,gltA and groEL genes for phylogenetic analyses. Sequence identities of partial DNA fragments of A. marginale...
Palavras-chave: Anaplasma marginale; Cattle; PCR; Philippines; Rhipicephalus (Boophilus) microplus.
Ano: 2013
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/3866

Serodiagnosis of Toxoplasma gondii in ducks from Behera Governorate, Egypt
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: AbouLaila, M; El-Bahy, N; Hilali, M; Yokoyama, N; Igarashi, I; 横山, 直明; 五十嵐, 郁男.
Toxoplasma gondii is an important zoonotic parasite. The diagnosis of infection in animals is an important tool to prevent human infection. In the present study, Toxoplasma gondii was diagnosed by using the modified agglutination test (MAT) in ducks from Behera Governorate, Egypt. The prevalence of Toxoplasma gondii was 13.9%. The prevalence of Toxoplasma gondii was the highest in the Native breed (17.65%) and in 6-8-months age group (19.4%). End-point titer of 1:25, 1:50, and 1:100 were recorded in 61.9%, 19.05%, and 19.05% of the positive samples, respectively. Duck meat is one source of the Toxoplasma gondii infection for human in Egypt.
Palavras-chave: Toxoplasma gondii; Modified agglutination test (MAT); Ducks; Egypt.
Ano: 2011
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/3128

糖鎖認識を基点としたバベシア原虫の赤血球侵入分子機構の解明
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: 横山, 直明; YOKOYAMA, NAOAKI.
2007年度～2009年度科学研究費補助金基盤研究(C) 研究成果報告書19580334
Palavras-chave: 寄生体生物.
Ano: 2010
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2763

Babesia bovis: Subcellular localization of host erythrocyte membrane components during their asexual growth
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: Okamura, Masashi; Yokoyama, Naoaki; Takabatake, Noriyuki; Okubo, Kazuhiro; Ikehara, Yuzuru; Igarashi, Ikuo; 横山, 直明; 五十嵐, 郁男.
In the present study, the subcellular localization of the host red blood cell (RBC) membrane components, the alpha 2-3-linked sialic acid (SA) residues and the lipid bilayer, was observed during the asexual growth of Babesia bovis using two erythrocyte probes, the SA-specific lectin (MALII) and the lipophilic fluorescent (PKH2) probes, respectively. In confocal laser scanning microscopy with MALII, the SA residues on the surface of parasitized RBCs appeared to accumulate into the intracellular parasites as the parasites matured as well as to remain on the surface of extracellular parasites. Furthermore, when PKH2-labeled RBCs were infected with B. bovis, PKH2 signals were also observed around both the intracellular and the extracellular parasites,...
Palavras-chave: Babesia bovis (B. bouis); SA; MALII; RBC; RT; PBS; Babesia equi (B. equi); PV.
Ano: 2007
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/1040

Effect of Oligomannose-Coated Liposome-Based Vaccine on Rodent Babesiosis
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: Ishigame, T; Takabatake, N; Iseki, H; Ota, N; Koyama, A; Igarashi, I; Nishikawa, Y; Ikehara, Y; Kojima, N; Yokoyama, N; 五十嵐, 郁男; 西川, 義文; 横山, 直明.
Oligomannose-coated liposome (OML)-based vaccines have been reported to induce Th1-based immunity against entrapped antigens in immunized animals and to show protective effects against several protozoal diseases. In the present study, we produced a recombinant Babesia rodhaini ribosomal phosphoprotein P0 (rBrP0) that showed immunological cross reactivity with another rodent Babesia parasite, B. microti. We evaluated the efficacy of vaccination with OML-entrapped rBrP0 on B. rodhaini and B. microti infections in mice. Prior immunization with the OML-based rBrP0 vaccine, or with a Freund’s adjuvant-based rBrP0 vaccine, failed to demonstrate any protective effect against lethal infection with B. rodhaini, but the OML-based vaccine did induce protective...
Palavras-chave: Oligomannose-coated liposomes (OML); Vaccine; Babesiosis; Babesia rodhaini; Babesia microti; P0.
Ano: 2009
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2383

A PCR Based Survey of Babesia ovata in Cattle from Various Asian, African and South American Countries
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: SIVAKUMAR, Thillaiampalam; ASADA, Masahito; BATTSETSEG, Badgar; HUANG, Xiaohong; LAN, Dinh Thi Bich; INPANKAEW, Tawin; P. YBAÑEZ, Adrian; ALHASSAN, Andy; THEKISOE, Oriel M. M.; DE MACEDO, Alan Caine Costa; INOKUMA, Hisashi; IGARASHI, Ikuo; YOKOYAMA, Naoaki; 猪熊, 壽; 五十嵐, 郁男; 横山, 直明.
Babesia ovata is a tick-transmitted hemoprotozoan parasite that infects cattle. In our study, bovine blood samples (n=2,034) were collected from 10 different countries (Brazil, China, Ghana, Japan, Mongolia, the Philippines, South Africa, Sri Lanka, Thailand and Vietnam) and DNA extracted. The DNA samples were screened using an established and specific polymerase chain reaction (PCR) assay targeting the Apical membrane antigen 1 (AMA-1) gene. Parasite DNA was detected among samples collected from Japan, Mongolia and Thailand. Sequence analyses confirmed that the PCR assay detected only B. ovata AMA-1, and that amplicons from different geographical locations were conserved. Our findings highlight the importance of designing adequate strategies to control B....
Palavras-chave: AMA-1; Babesia ovata; Cattle; Mongolia; Thailand.
Ano: 2013
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/4016

Genotypic Diversity of Theileria orientalis Detected from Cattle Grazing in Kumamoto and Okinawa Prefectures of Japan
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: YOKOYAMA, Naoaki; UENO, Akio; MIZUNO, Daisuke; KUBOKI, Noritaka; KHUKHUU, Altangerel; IGARASHI, Ikuo; MIYAHARA, Tokuji; SHIRAISHI, Takashi; KUDO, Ryuta; OSHIRO, Mamoru; ZAKIMI, Satoshi; SUGIMOTO, Chihiro; MATSUMOTO, Kotaro; INOKUMA, Hisashi; 横山, 直明; 五十嵐, 郁男; 松本, 高太郎; 猪熊, 壽.
Theileria orientalis is a benign protozoan species that is widely distributed in Japan, yet sometimes causes serious economic losses in the livestock industry. In this study, we conducted a molecular survey based on genes encoding the major piroplasm surface protein (MPSP) and p23 for T. orientalis detected in cattle grazing in southern areas of Japan, consisting of 2 farms in Kumamoto prefecture (Aso and Kuma districts) and 3 farms in Okinawa prefecture (Ishigaki, Iriomote, and Yonaguni Islands). High prevalence rates of T. orientalis infection were shown in all the cattle populations using the diagnostic MPSP- and p23-PCR assays. Phylogenetic analyses revealed 4 MPSP genotypes and 3 p23 genotypes. Furthermore, MPSP genotype-specific PCR methods were...
Palavras-chave: Cattle; Genotype-specific PCR; Japan; MPSP gene; Theileria orientalis.
Ano: 2011
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/3584

In vitro growth inhibitory effect of (-)-Epigallocatechin-3-gallate from green tea on the growth of equine Babesia parasites
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: AbouLaila, M; Terkawi, M.A.; Yokoyama, N; Igarashi, I; 横山, 直明; 五十嵐, 郁男.
Palavras-chave: (-)-Epigallocatechin-3-gallate; In vitro; Babesia caballi; Babesia equi.
Ano: 2011
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/3124

Inhibitory Effects of Pepstatin A and Mefloquine on the Growth of Babesia Parasites
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: Munkhjargal, Tserendorj; AbouLaila, Mahmoud; Mohamad Alaa Terkawi; Sivakumar, Thillaiampalam; Ichikawa, Madoka; Davaasuren, Batdorj; Nyamjargal, Tserendorj; Yokoyama, Naoaki; Igarashi, Ikuo; 横山, 直明; 五十嵐, 郁男.
We evaluated the inhibitory effects of pepstatin A and mefloquine on the in vitro and in vivo growths of Babesia parasites. The in vitro growth of Babesia bovis, B. bigemina, B. caballi, and B. equi was significantly inhibited (P &lt; 0.05) by micromolar concentrations of pepstatin A (50% inhibitory concentrations = 38.5, 36.5, 17.6, and 18.1 μM, respectively) and mefloquine (50% inhibitory concentrations = 59.7, 56.7, 20.7, and 4 μM, respectively). Furthermore, both reagents either alone at a concentration of 5 mg/kg or in combinations (2.5/2.5 and 5/5 mg/kg) for 10 days significantly inhibited the in vivo growth of B. microti in mice. Mefloquine treatment was highly effective and the combination treatments were less effective than other treatments....
Ano: 2012
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/3829