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| Registros recuperados: 32 | |
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| Zhang, Houshuang; Lee, Eung-goo; Liao, Min; Compaore, Muller K.A.; Zhang, Guohong; Kawase, Osamu; Fujisaki, Kozo; Sugimoto, Chihiro; Nishikawa, Yoshifumi; Xuan, Xuenan. |
| The characterization of the cross-reactive antigens of two closely related apicomplexan parasites, Neospora caninum and Toxoplasma gondii, is important to elucidate the common mechanisms of parasite–host interactions. In this context, a gene encoding N. caninum ribosomal phosphoprotein P0 (NcP0) was identified by immunoscreening of a N. caninum tachyzoite cDNA expression library with antisera from mice immunized with T. gondii tachyzoites. The NcP0 was encoded by a gene with open reading frame of 936 bp, which encoded a protein of 311 amino acids. The NcP0 gene existed as a single copy in the genome and was interrupted by a 432 bp intron. The NcP0 showed 94.5% amino acid identity to T. gondii P0 (TgP0). Anti-recombinant NcP0 (rNcP0) sera recognized a... |
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Palavras-chave: Neospora caninum; Toxoplasma gondii; Ribosomal phosphoprotein P0; Cross-reactive. |
| Ano: 2007 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/1035 |
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| Xuan, Xuenan; Zhang, Sofa; Kamio, Tsugihiko; Tsushima, Y.; Kamada, Takenori; Nishikawa, Yoshifumi; Otsuka, Haruki; Karanis, Panagiotis; Igarashi, Ikuo; Nagasawa, Hideyuki; Fujisaki, Kozo; Mikami, Takeshi; 玄, 学南; 西川, 義文; 五十嵐, 郁男. |
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Palavras-chave: C. parvum; P15; Vaccinia virus; Subunit vaccine. |
| Ano: 1999 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/314 |
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| Fereig, Ragab M.; Mahmoud, Hassan Y.A.H.; Mohamed, Samy G.A.; AbouLaila, Mahmoud Rezk; Abdel-Wahab, Azza; Osman, Salama Ahmed; Zidan, Sherif Abdallah; El-Khodary, Sabry A.; Mohamed, Adel Elsayed Ahmed; Nishikawa, Yoshifumi. |
| Toxoplasmosis is a cosmopolitan protozoan disease that has been recorded in a wide range of vertebrate hosts, including humans. In response to the paucity of available data, this study was undertaken to comprehensively establish the seroprevalence of Toxoplasma gondii among various farm animals in different localities of Egypt. The latex agglutination test and TgGRA7-based enzyme-linked immunosorbent assay were used to screen the investigated animals for anti-T. gondii IgG antibodies. When only samples with simultaneously positive results for both the latex agglutination test and the TgGRA7-based ELISA were considered positive, 174 (26.7%) of 652 serum samples from different animals were seropositive. The prevalence of antibodies according to species was:... |
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Palavras-chave: Egypt; Seroprevalence; Toxoplasma gondii; Toxoplasmosis. |
| Ano: 2016 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/4545 |
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| Jia, Honglin; Nishikawa, Yoshifumi; Luo, Yuzi; Yamagishi, Junya; Sugimoto, Chihiro; Xuan, Xuenan. |
| The M17 family leucine aminopeptidase (LAP) hydrolyze amino acids from the N-terminus of peptides. Many LAPs from parasitic protozoa including Plasmmodium, Trypanosoma and Leishmania, have been intensely investigated because of their crucial roles in parasite biology. In this study, a functional recombinant Toxoplasma gondii LAP (rTgLAP) was expressed in Escherichia coli and its enzymatic activity against synthetic substrates for aminopeptidase, as well as the cellular localization was determined. Our results indicated that TgLAP is a functional aminopeptidase in the cytoplasma of T. gondii. |
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Palavras-chave: Toxoplasma gondii; Leucine aminopeptidase; Enzymatic activity. |
| Ano: 2010 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2822 |
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| Bannai, Hiroshi; Nishikawa, Yoshifumi; Seo, Jin-yong; Nakamura, Chinatsu; Zhang, Sofa; Kimata, Isao; Takashima, Yasuhiro; Li, Junyou; Igarashi, Ikuo; Xuan, Xuenan; 西川, 義文; 五十嵐, 郁男; 玄, 学南. |
| An enzyme-linked immunosorbent assay (ELISA) based on the recombinant p23 of Cryptosporidium parvum was established for the detection of antibodies against C. parvum in cattle. The sensitivity and specificity of the ELISA were evaluated with the standard indirect fluorescent antibody test (IFAT) using sporozoites as antigens. Of 77 bovine sera collected from China, 20 (26.0%) were identified as positive by the IFAT. The same samples were tested with the ELISA. The optical densities at 415 nm were compared to the IFAT results and statistically analyzed to designate a provisional cut-off point. As a result, the cut-off point was concluded to be 0.08, which was considered to be the best condition in the light of its sensitivity (80%) and specificity (73.7%).... |
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Palavras-chave: Cryptosporidium parvum; P23; ELISA; IFAT. |
| Ano: 2006 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/142 |
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| Zhang, Houshuang; Compaore, Muller K.A.; Lee, Eung-goo; Liao, Min; Zhang, Guohong; Sugimoto, Chihiro; Fujisaki, Kozo; Nishikawa, Yoshifumi; Xuan, Xuenan. |
| The cross-reactive antigens of Neospora caninum and Toxoplasma gondii are important in the exploration to determine the common mechanisms of parasite-host interaction. In this study, a gene encoding N. caninum apical membrane antigen 1 (NcAMA1) was identified by immunoscreening of a N. caninum tachyzoite cDNA expression library with antisera. from mice immunized with recombinant T gondii apical membrane antigen 1 (TgAMA 1). NcAMA1 was encoded by an open reading frame of 1695 bp, which encoded a protein of 564 amino acids. The single-copy NcAMA1 gene was interrupted by seven introns. NcAMA1 showed 73.6% amino acid identity to TgAMA1. Mouse polyclonal antibodies raised against the recombinant NcAMA1 (rNcAMA1) recognized a 69-kDa native parasite protein by... |
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Palavras-chave: Neospora caninum; Toxoplasma gondii; Apical membrane antigen 1; Cross-reactive; Invasion. |
| Ano: 2007 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/1034 |
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| Umeda, Kousuke; Tanaka, Sachi; Ihara, Fumiaki; Yamagishi, Junya; Suzuki, Yutaka; Nishikawa, Yoshifumi. |
| Background: Toxoplasma gondii is capable of persisting in the brain, although it is efficiently eliminated by cellular immune responses in most other sites. While Toll-like receptor 2 (TLR2) reportedly plays important roles in protective immunity against the parasite, the relationship between neurological disorders induced by T. gondii infection and TLR2 function in the brain remains controversial with many unknowns. In this study, primary cultured astrocytes, microglia, neurons, and peritoneal macrophages obtained from wild-type and TLR2-deficient mice were exposed to T. gondii tachyzoites. To characterize TLR2-dependent functional pathways activated in response to T. gondii infection, gene expression of different cell types was profiled by RNA... |
| Ano: 2017 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/4581 |
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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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| 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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| Mahmoud, Motamed Elsayed; Fereig, Ragab; Nishikawa, Yoshifumi. |
| Toxoplasma gondii is a pathogen relevant to psychiatric disorders. We recently showed that reactivation of chronic T. gondii infection induced depression-like behaviors in mice. Furthermore, it has been hypothesized that depression-like behaviors are mediated via a host defense mechanism against invading pathogens; proximate mechanisms of this behavioral hypothesis remain unclear. In the present study, we investigate the contribution of indoleamine 2,3-dioxygenase (IDO), inflammation, and interferon gamma (IFN-gamma) to anhedonic and despair-related behaviors in T. gondii-infected mice by using sucrose preference and forced-swim tests, respectively. First, we confirmed that BALB/c mice exhibited both sickness and depression-like behaviors during acute... |
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Palavras-chave: Toxoplasma gondii; 1-methyl tryptophan; Minocycline; Interferon gamma; Sickness behavior; Anhedonic behavior; Despair-like behavior. |
| Ano: 2017 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/4507 |
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| Terkawi, M. A.; Aboge, G.; Jia, H.; Goo, Y-K.; Ooka, H.; Yamagishi, Junya; Nishikawa, Yoshifumi; Kawazu, Shin-ichiro; Fujisaki, K.; Xuan, Xuenan; 山岸, 潤也; 西川, 義文; 河津, 信一郎; 玄, 学南. |
| A novel gene encoding 27-kDa protein was identified by the screening of Babesia gibsoni cDNA library with acutely infected dog serum. The BgP27 is a single copy gene with a predicted open reading frame of 762 bp and 254 amino acids. The phylogenic analysis of the deduced amino acid of BgP27 demonstrated considerable identities with members of Plasmodium berghei circumsporozoite protein family that ranged between 18.4% and 22.8%. The BgP27 was expressed as a glutathione S-transferase fusion protein in Escherichia coli. The serum raised in mice against the recombinant protein specifically reacted with a 27-kDa protein in the extracts of B. gibsoni parasites. Confocal laser scanning microscopic observation showed high fluorescent reactivity with both... |
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Palavras-chave: Babesia gibsoni; Enzyme-linked immunosorbent assay; Deiagnostic performance. |
| Ano: 2008 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2232 |
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| Zhou, Mo; Cao, Shinuo; Sevinc, Ferda; Sevinc, Mutlu; Ceylan, Onur; Liu, Mingming; Wang, Guanbo; Moumouni, Paul Franck Adjou; Jirapattharasate, Charoonluk; Suzuki, Hiroshi; Nishikawa, Yoshifumi; Xuan, Xuenan. |
| Considering the scarce information on occurrences of Toxoplasma gondii and Neospora caninum in domestic animals from Turkey, the aim of this study was to investigate the seroprevalence of these parasite infections in cattle, horses, sheep, goats and dogs in Turkey. The specific antibodies against T gondii and N. caninum were detected by iELISAs based on the recombinant TgSAG2 or NcSAG1 in a total of 2,039 serum samples from eleven provinces. The seroprevalence of T. gondii infections was 46.3%, 4.0%, 20.0%, 12.9% and 19.8%, that of N. caninum infections was 0.3%, 7.4%, 2.1%, 3.2% and 16.6% in the horses, cattle, sheep, goats and dogs, respectively. These results indicated that T gondii and N. caninum infections are prevalent in Turkish domestic animals. |
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Palavras-chave: ELISA; Neospora caninum; Toxoplasma gondii; Turkey. |
| Ano: 2016 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/4422 |
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| Leesombun, Arpron; Boonmasawai, Sookruetai; Nishikawa, Yoshifumi. |
| Neosporosis has a worldwide distribution and causes economic losses in farming, particularly by increasing the risk of abortion in cattle. This study investigated the effects of Thai piperaceae (Piper betle, P. nigrum, and P. sarmentosum) extracts on Neospora caninum infections in vitro and in vivo. In an in vitro parasite growth assay based on the green fluorescent protein (GFP) signal, P. betle was the most effective extract at inhibiting parasite growth in human foreskin fibroblast cells (IC50 of GFP-expressing N. caninum parasites, 22.1 mu g/ml). The P. betle extract, at 25 mu g per ml, inhibited parasite invasion into host cells. Furthermore, in two independent experiments, treating N. caninum-infected mice with the P. betle extract for 7 days... |
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Palavras-chave: Neospora caninum; Neosporosis; Piper betle; Piper nigrum; Piper sarmentosum; Ethanol extract. |
| Ano: 2017 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/4578 |
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| Fereig, Ragab M.; Mohamed, Samy G. A.; Mahmoud, Hassan Y. A. H.; AbouLaila, Mahmoud Rezk; Guswanto, Azirwan; Thu-Thuy Nguyen; Mohamed, Adel Elsayed Ahmed; Inoue, Noboru; Igarashi, Ikuo; Nishikawa, Yoshifumi. |
| Babesia bovis, B. bigemina, Trypanosoma evansi, and Anaplasma marginate infections cause serious diseases in cattle, and are primarily transmitted by arthropod vectors (ticks for B. bovis, B. bigemina, and A. marginate and various types of flies for T. evansi). In the last few years, there have been many reports of a high prevalence of certain protozoan infections in northern Egypt, but no accurate or adequate data are available for the southern regions. Therefore, in this study, we screened for evidence of such diseases in economically important cattle species using serum samples. The seroprevalence of protozoan infections in cattle was determined with enzyme-linked immunosorbent assays using species-specific diagnostic antigens. In a total of 301 cattle... |
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Palavras-chave: Babesia bovis; Babesia bigemina; Trypanosoma evansi; Anaplasma marginale; Cattle; Egypt. |
| Ano: 2017 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/4579 |
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| Hara, Olgga A; Liao, Min; Baticados, Waren; Bannai, Hiroshi; Zhang, Guohong; Zhang, Sofa; Lee, Eung-goo; Nishikawa, Yoshifumi; Claveria, Florencia G.; Igarashi, Makoto; Nagasawa, Hideyuki; Xuan, Xuenan. |
| Neospora caninum infection is an important disease affecting bovine and canine populations worldwide. The dense granule antigen 7 of N. caninum (NcGRA7) is considered to be an immunodominant antigen. In the present study, the gene encoding truncated NcGRA7 (NcGRA7t) lacking an N-terminal signal peptide was expressed in Escherichia coli, and its diagnostic potential in an enzyme-linked immunosorbent assay (ELISA) was evaluated. The ELISA could clearly discriminate between known N. caninum-positive and -negative sera from dogs. Serum samples randomly collected from dogs in Japan and China were examined for the diagnosis of neosporosis using the ELISA. Twenty-three of 135 samples (17.03%) and 9 of 95 (9.47%) samples from Japan and China, respectively, were... |
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Palavras-chave: Canine; ELISA; Neospora caninum; NcGRA7. |
| Ano: 2006 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/995 |
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| Fereig, Ragab M.; AbouLaila, Mahmoud Rezk; Mohamed, Samy G. A.; Mahmoud, Hassan Y. A. H.; Ali, Alsagher O.; Ali, Asmaa F.; Hilali, Mosaad; Zaid, Anis; Mohamed, Adel Elsayed Ahmed; Nishikawa, Yoshifumi. |
| Neospora caninum and Cryptosporidium parvum are intracellular protozoan parasites that are distributed worldwide and of major economical concern in cattle industry. N. caninum can cause abortion storms and high culling rates, whereas C. parvum has zoonotic implications and can cause diarrhea in calves. There are currently no data on the prevalence of neosporosis and cryptosporidiosis in humans or animals in southern Egypt. Prevalence of these two infections was determined in a sample of cattle from two different areas in southern Egypt, Sohag and Qena, using enzyme-linked immunosorbent assay. A total 301 cattle were sampled, of which 18.9% were positive for N. caninum, 35.9% were positive for C parvum and 10.0% were positive for both. Geographical location... |
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Palavras-chave: Cattle; Cryptosporidium parvum; Neospora caninum; ELISA; Egypt. |
| Ano: 2016 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/4531 |
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| Nishikawa, Yoshifumi. |
| Neosporosis is caused by the intracellular protozoan parasite Neospora caninum. This major disease-causing pathogen is responsible for inducing abortion in cattle, and these adverse events occur sporadically all over the world, including Japan. Currently, there are no vaccines on the market against infection with N. caninum. Because live and attenuated vaccines against N. caninum have had safety and effectiveness issues, development of a next-generation vaccine is urgently required. To develop a vaccine against neosporosis, my laboratory has been focused on the following: 1) understanding the host immune responses against Neospora infection, 2) identifying vaccine antigens and 3) developing an effective antigen-delivery system. The research strategy taken... |
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Palavras-chave: Adjuvant; Cattle; Neospora caninum; Neosporosis; Vaccine. |
| Ano: 2017 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/4544 |
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| Ihara, Fumiaki; Nishimura, Maki; Muroi, Yoshikage; Mahmoud, Motamed Elsayed; Yokoyama, Naoaki; Nagamune, Kisaburo; Nishikawa, Yoshifumi. |
| Chronic infection with Toxoplasma gondii becomes established in tissues of the central nervous system, where parasites may directly or indirectly modulate neuronal function. Epidemiological studies have revealed that chronic infection in humans is a risk factor for developing mental diseases. However, the mechanisms underlying parasite-induced neuronal dysfunction in the brain remain unclear. Here, we examined memory associated with conditioned fear in mice and found that T. gondii infection impairs consolidation of conditioned fear memory. To examine the brain pathology induced by T. gondii infection, we analyzed the parasite load and histopathological changes. T. gondii infects all brain areas, yet the cortex exhibits more severe tissue damage than other... |
| Ano: 2016 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/4480 |
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| Ybañez, Rochelle Haidee D.; Leesombun, Arpron; Nishimura, Maki; Matsubara, Ryuma; Kojima, Mikiko; Sakakibara, Hitoshi; Nagamune, Kisaburo; Nishikawa, Yoshifumi. |
| Neospora caninum causes abortion and stillbirth in cattle. Identification of effective drugs against this parasite remains a challenge. Previous studies have suggested that disruption of abscisic acid (ABA)-mediated signaling in apicomplexan parasites such as Toxoplasma gondii offers a new drug target. In this study, the ABA inhibitor, fluridone (FLU), was evaluated for its action against N. caninum. Production of endogenous ABA within N. caninum was confirmed by ultra-performance liquid chromatography-tandem quadruple mass spectrometry. Subsequently, FLU treatment efficacy was assessed using in vitro. Results revealed that FLU inhibited the growth of N. caninum and T. gondii in vitro (IC50 143.1 +/- 43.96 mu M and 330.6 +/- 5238 mu M, respectively).... |
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Palavras-chave: Neospora caninum; Fluridone; Abscisic acid. |
| Ano: 2016 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/4491 |
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| Registros recuperados: 32 | |
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