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| Registros recuperados: 31 | |
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| Sivakumar, Thillaiampalam; Kothalawala, Hemal; Weerasooriya, Gayani; Seekkuge Susil Priyantha Silva; Puvanendiran, Sumathy; Munkhjargal, Tserendorj; Igarashi, Ikuo; Yokoyama, Naoaki. |
| Throughout the world, infections with the Babesia and Theileria parasites often result in economically significant clinical disease in cattle. We conducted a longitudinal survey of Babesia and Theileria infections in cattle from the Polonnaruwa (n?=?75; dry zone) and Nuwara Eliya (n?=?161; wet zone) districts of Sri Lanka. DNA from blood samples collected in June, September, and December 2014 and March 2015 was screened for Babesia bovis, Babesia bigemina, Theileria annulata and Theileria orientalis using specific polymerase chain reactions (PCRs). Additionally, serum samples collected from the animals were screened using enzyme-linked immunosorbent assays (ELISAs) to detect B. bovis- and B. bigemina-specific antibodies. All of the animals surveyed in... |
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Palavras-chave: Babesia; Cattle; Longitudinal study; Sri Lanka; Theileria. |
| Ano: 2016 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/4567 |
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| Musinguzi, Simon Peter; Suganuma, Keisuke; Asada, Masahito; Laohasinnarong, Dusit; Sivakumar, Thillaiampalam; Yokoyama, Naoaki; Namangala, Boniface; Sugimoto, Chihiro; Suzuki, Yasuhiko; Xuan, Xuenan; Inoue, Noboru. |
| We screened cattle and goats from the districts of Chama, Monze and Mumbwa in Zambia for animal African trypanosomes, Babesia bigemina and Theileria parva using PCRs; 38.1% of the samples tested positive for at least one of the parasite species. The most common parasite was Trypanosoma vivax (19.8%). Its incidence was significantly higher in goats than in cattle, (P<0.05). B. bigemina was found in samples from all the three areas, making it the most widespread of the parasites in Zambia. Among the tested samples, 12.0% of the positive samples were mixed infections. There were significant differences in the infection rates of T. vivax (Mumbwa had a significantly higher infection rate [39.6%, P<0.0001]), Th. parva (Monze had the only cases... |
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Palavras-chave: Animal African trypanosomosis; Cattle; Goat; Piroplasmosis; Zambia. |
| Ano: 2016 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/4389 |
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| 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. |
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Palavras-chave: Adjuvant; African trypanosome; Immunization; Oligomannose-coated liposome(OML). |
| Ano: 2008 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2222 |
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| Okubo, Kazuhiro; Yokoyama, Naoaki; Govind, Yadav; Alhassan, Andy; Igarashi, Ikuo. |
| In the present study, we examined the effects of four kinds of cysteine protease inhibitors (E64, E64d, leupeptin, and ALLN) on the in vitro asexual growth of Babesia bovis. Of these, only the lipophilic inhibitors, E64d and ALLN, were found to effectively inhibit the growth of B. bovis. In further experiments, E64d, but not ALLN, significantly suppressed the parasite’s invasion of host erythrocytes, while both chemicals, especially ALLN, inhibited the parasite’s replication within the infected erythrocytes. These data suggested the presence of cysteine protease(s) derived from B. bovis, in which the protease(s) would play important roles in the erythrocyte invasion and/or replication processes of the parasite. |
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Palavras-chave: Babesia bovis; Cysteine protease; Inhibitor; Invasion; Replication. |
| Ano: 2007 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/1041 |
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| 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,... |
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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 |
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| Sivakumar, Thillaiampalam; Igarashi, Ikuo; Yokoyama, Naoaki. |
| Babesia ovata, which is transmitted by Haemaphysalis longicornis, is an intraerythrocytic protozoan parasite of cattle. Based on its morphology, B. ovata is classified as a large-type Babesia. The developmental stages of B. ovata have been described both in cattle and the tick vector. In infected adult female ticks, the parasite is transovarially transmitted to the tick eggs. The sexual reproduction of B. ovata has been demonstrated in the tick midgut. The diagnostic tools that are currently available for the specific detection of B. ovata in cattle include microscopy and polymerase chain reaction assays. The development of improved molecular and serological diagnostic tools has been constrained by the limited availability of genetic data. B. ovata has... |
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Palavras-chave: Babesia ovata; Cattle; Epidemiology; Phylogeny; Taxonomy. |
| Ano: 2016 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/4555 |
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| Matsuo, Tomohide; Yokoyama, Naoaki; Suthisak, Boonchit; Fujisaki, Kozo; Igarashi, Ikuo. |
| We examined the detailed cellular localization of the rhoptry-associated protein-1 (RAP-1) of Babesia bovis merozoites by the post-embedding method of immuno-electron microscopy (IEM) using the anti-RAP-1 monoclonal antibody (mAb) 1C1 in order to substantiate the result in our previous report by an indirect immunofluorescent antibody test and the pre-embedding method of IEM. RAP-1 slightly distributed only in cytoplasm of merozoites, especially around the nucleus, but not in the rhoptry organelle at an early stage after invasion into a red blood cell. Then, the RAP-1 was accumulated in the rhoptry organelle and was also found in the iRBC cytoplasm, which suggests that synthesis and release of RAP-1 may occur in the iRBC. Finally, the RAP-1 was found within... |
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Palavras-chave: Babesia bovis RAP-1 invasion; Escape RBC. |
| Ano: 2005 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/145 |
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| Ihara, Fumiaki; Nishimura, Maki; Muroi, Yoshikage; Furuoka, Hidefumi; Yokoyama, Naoaki; Nishikawa, Yoshifumi. |
| Neospora caninum is an obligate intracellular parasite that causes neurological disorders in dogs and cattle. The majority of host animals are asymptomatic at the chronic stage of infection. However, it remains unclear whether cerebral function is normal in asymptomatic animals. In this study, mice were infected with N. caninum (strain Nc-1) and their brains were examined to understand changes in cerebral function at the chronic stage of infection. Mice infected with N. caninum showed impaired locomotor activity, but no differences in clinical symptoms were observed. In the brains of infected mice, parasites were distributed throughout the brain and histological lesions were observed everywhere except for the cerebellum. Expression levels of... |
| Ano: 2016 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/4460 |
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| 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. |
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Palavras-chave: Babesia gibsoni; Babesia canis; CDNA library; ELISA; P30 gene. |
| Ano: 2002 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/624 |
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| Tattiyapong, Muncharee; Sivakumar, Thillaiampalam; Takemae, Hitoshi; Simking, Pacharathon; Jittapalapong, Sathaporn; Igarashi, Ikuo; Yokoyama, Naoaki. |
| Babesia bovis, an intraerythrocytic protozoan parasite, causes severe clinical disease in cattle worldwide. The genetic diversity of parasite antigens often results in different immune profiles in infected animals, hindering efforts to develop immune control methodologies against the B. bovis infection. In this study, we analyzed the genetic diversity of the merozoite surface antigen-1 (msa-1) gene using 162 B. bovis-positive blood DNA samples sourced from cattle populations reared in different geographical regions of Thailand. The identity scores shared among 93 msa-1 gene sequences isolated by PCR amplification were 43.5-100%, and the similarity values among the translated amino acid sequences were 42.8-100%. Of 23 total clades detected in our... |
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Palavras-chave: Antigenicity variation; Babesia bovis; Msa-1; Genetic diversity; Thailand. |
| Ano: 2016 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/4490 |
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| Ybañez, Adrian Patalinghug; Ybañez, Rochelle Haidee D.; Claveria, Florencia G.; Cruz-Flores, Mary Jane; Xuenan, Xuen; Yokoyama, Naoaki; Inokuma, Hisashi. |
| A total of 658 cattle in 6 provinces in the Philippines were screened for Anaplasma marginale infection by using a diagnostic heat-shock operon (groEL) gene-PCR assay. The screening-positive samples were further tested using the major surface antigen protein 1a (Msp1a) gene-PCR assay. Screening PCR results showed 130 cattle (19.8%) were positive for the A. marginale infection. Subsequent amplification using the Msp1a gene only showed 93 samples (14.1%) to be positive. In addition, 37 tandem-repeat structures, including 20 novel structures, and 41 distinct genotypes were identified. Interestingly, multiple infections of 4 different genotypes were also observed in A. marginale-infected cattle. The present study demonstrated the prevalence and... |
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Palavras-chave: Anaplasma marginale; Cattle; GroEL; Msp1a; Philippines. |
| Ano: 2014 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/4011 |
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| 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... |
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Palavras-chave: In vitro; Babesia; Clotrimazole; Ketoconazole; Clodinafop-propargyl. |
| Ano: 2003 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/637 |
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| 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... |
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Palavras-chave: Fosmidomycin; Babesia bovis; Babesia bigemina; Asexual growth; In vitro culture. |
| Ano: 2008 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2235 |
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| 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 < 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 |
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| 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 |
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| Adrian Patalinghug Ybañez; Rochelle Haidee Daclan Ybañez; Yokoyama, Naoaki; Inokuma, Hisashi. |
| Aim: Anaplasma platys, the causative agent of infectious canine cyclic thrombocytopenia, is a tick-borne pathogen that also has been implicated as potentially zoonotic. To provide molecular evidence on the multiple infections of A. platys variants in Philippine dogs. Materials and Methods: DNA fragments of A. platys from infected dogs in the Philippines were molecularly characterized. For screening, 25 dogs suspected to have canine anaplasmosis were tested using a 16S rRNA-based nested polymerase chain reaction (PCR). Infection was confirmed by sequencing of positive amplicons. Second round PCR targeting a longer 16S rRNA fragment was subsequently performed on the first round PCR amplicons of the positive samples. Further characterization using the... |
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Palavras-chave: Anaplasma platys; Dogs; Philippines; Variants. |
| Ano: 2016 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/4537 |
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| Registros recuperados: 31 | |
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