خيارات البحث
النتائج 1 - 10 من 11
Effects of anti-tick cocktail vaccine against Rhipicephalus appendiculatus
2008
Imamura, S.(Hokkaido Univ., Sapporo (Japan)) | Konnai, S. | da Silva Vaz, I.Jr. | Yamada, S. | Nakajima, C. | Ito, Y. | Tajima, T. | Yasuda, J. | Simuunza, M. | Onuma, M. | Ohashi, K.
Rhipicephalus appendiculatus serpin-3 (RAS-3), R. appendiculatus serpin-4 (RAS-4) and a 36kDa immuno-dominant protein of R. appendiculatus (RIM36) were reported as candidate antigens for the anti-tick vaccine to control ixodid ticks. In the present study, we generated recombinant proteins of RAS-3 (rRAS-3), RAS-4 (rRAS-4) and RIM36 (rRIM36), and assessed their potency as an anti-tick cocktail vaccine in cattle model. RT-PCR analysis showed that RAS-3, RAS-4 and RIM136 transcripts were detected in both adult male and female ticks during feeding. Immunization of cattle with the combination of rRAS-3, rRAS-4 and rRIM36 had raised antibodies against all recombinants and anti-sera had reacted with the molecules from the tick salivary gland extract. Tick infestation challenge demonstrated protective immunity against female ticks, resulting in mortality rates of 39.5 and 12.8 % for the vaccinated and control groups, respectively. Moreover, the mortality rate of Theileria parva-infected female ticks was 48.5 and 10.8 % in the vaccinated and control group, respectively. In order to evaluate the levels of pathogen transmission capacity by T. parva-infected ticks fed on immunized cattle, the occurrence of T. parva in the bovine parotid lymph node and peripheral blood was also determined and quantified by real-time PCR. Although the infection with T. parva could not be protected by the vaccine, the occurrence of pathogen in peripheral blood was delayed 1 to 2 days after the infestation challenge in vaccinated group. These results suggest that this cocktail vaccine plays a role in the prevention of tick infestation.
اظهر المزيد [+] اقل [-]Experimental transmission of bovine leukemia virus in cattle via rectal palpation
2006
Kohara, J.(Hokkaido. Animal Research Center, Shintoku (Japan)) | Konnai, S. | Onuma, M.
We examined whether Bovine leukemia virus (BLV) was transmitted by rectal palpation using a common sleeve between a BLV-infected cow and BLV- negative steers. Three of four steers developed antibodies against BLN as determined by agar-gel immunodiffusion (AGID) test between 7 to 10 weeks after the first rectal palpation using common sleeves from BLV-infected cow. In the steers, BLV proviral DNA were detected by PCR 1 to 5 weeks earlier than detection of the antibodies by the AGID test. Our experiments demonstrated that rectal palpation is a potential cause of BLV spread in herds and that detection of BLV proviral DNA in cattle by PCR is useful screening test for early diagnosis of BLV infection.
اظهر المزيد [+] اقل [-]Polymerase chaine reaction-restriction fragment length polymorphism (PCR-RFLP) method for mtDNA typing in Hokkaido brown bear (Ursus arctos yesoensis) [Japan]
2003
Satoh, Y. (Hokkaido Univ., Sapporo (Japan)) | Mano, T. | Tsuruga, H | Masuda, R. | Matsuhashi, T. | Onuma, M. | Suzuki, M. | Ohtaishi, N.
A rapid and highly sensitive method for diagnosis of equine influenza by antigen detection using immuno-PCR
2001
Ozaki, H. (Hokkaido Univ., Sapporo (Japan)) | Sugita, S. | Kida, H.
A rapid and simple transcriptional sequencing method for GC-rich DNA regions
2006
Izawa, M.(Nippon Genetech Co. Ltd., Toyama (Japan)) | Kitamura, N. | Odake, N. | Maki, F. | Kanehira, K. | Nemoto, H. | Yamaguchi, M. | Yamashita, A. | Sasaki, N. | Hattori, M. | Kanayama, S. | Yoneda, Y.
In genome sequencing project, we encounter the DNA regions that often contain stable secondary structure with high GC content. These regions are difficult to not only amplify by PCR for template preparations, but also deter mine the DNA sequences using standard Cycle sequencing (CS) method. Transcriptional sequencing (TS) is a unique DNA sequencing method using RNA polymerase, and is based on the principles of the chain-termination method, which is a powerful method to analyze GC-rich sequences. In this study, we examined the multiple displacement amplification (MDA) to overcome low efficiency of PCR amplification in GC-rich regions and subjected to TS reaction. Combination of MDA and TS (MDA-TS) was extremely successful with GC content ranging from 65 % to 85%, which are difficult to analyze with PCR and CS. We also report plasmid vector, pTS1, which has the stronger T7 and T3 promoters than those of conventional vectors, and the sequence that decreases transcriptional efficiency was removed from its multiple cloning sites. pTS1 resulted in the improved sequencing accuracy and reduced reaction time up to 5 min. These results showed that MDA-TS is a rapid and accurate method for the analysis of GC-rich templates.
اظهر المزيد [+] اقل [-]Distribution of bovine immunodeficiency virus in the organs of experimentally infected cows
1997
Tajima, M. (Hokkaido Univ., Sapporo (Japan)) | Sato, N. | Kirisawa, R. | Onuma, M. | Maede, Y.
The distribution of bovine immunodeficiency virus (BIV) in the organs of experimentally infected cows was investigated by use of nested polymerase chain reaction (PCR). Two cows (Nos. 1 and 2) experimentally infected with BIV were alive without any clinical symptoms of BIV infection for 28 months. Viral and proviral genomes of BIV were continuously detected from peripheral blood leukocytes in those cows by nested PCR. Proviral genome of BIV were also detected in liver, lung, and spleen cells in the two cows, and in the brain in cow No.1. Viral genomes were detected in liver, lung and spleen cells in cow No.1, and detected only in spleen cells in cow No.2. These results suggest that BIV tended to the persistent in some organs, especially in the spleen
اظهر المزيد [+] اقل [-]Detection of viral genome in non-neural tissues of cattle experimentally infected with bovine herpesvirus 1
1996
Mweene, A.S. (Hokkaido Univ., Sapporo (Japan)) | Okazaki, K. | Kida, H.
Availability of oral swab sample for the detection of bovine viral diarrhea virus (BVDV) gene from the cattle persistently infected with BVDV
2008
Tajima, M.(Hokkaido Univ., Sapporo (Japan)) | Ohsaki, T. | Okazawa, M. | Yasutomi, I.
Bovine nasal and oral discharges were used as samples for bovine viral diarrhea virus (BVDV) gene detection. Viral genes in serum (S), nasal discharge (N) and oral discharge (O) were quantified with real-time polymerase chain reaction using SYBR Green by the relative quantification method, and findings were compared among samples. Although the quantity of the BVDV gene in S was greater than those in N and O, all samples were available to identify persistently infected (PI) cattle with BVDV by reverse transcription polymerase chain reaction (RT-PCR). The swab samples were able to be stored for a few days at 4degC with a little decrease of amplification signal in RT-PCR. Oral swab sampling was easier than nasal swab sampling, and was also less uncomfortable for the cattle than other sampling methods without pain or unnecessary retention. This sampling method can be performed without any special technique and equipment. Therefore, the oral swab sampling method is useful for screening to detect BVDV PI cattle by RT-PCR.
اظهر المزيد [+] اقل [-]Gene expression profile of bovine bone marrow mesenchymal stem cell during spontaneous chondrogenic defferentiation in pellet culture system
2006
Bosnakovski, D.(Hokkaido Univ., Sapporo (Japan)) | Mizuno, M. | Kim, G. | Takagi, S. | Okumura, M. | Fujinaga, T.
Bovine bone marrow mesenchymal stem cells (MSCs) cultured in condensate culture, spontaneous and independent for any external biostimulants, undergo chondrogenic differentiation. In the present study, the bovine MSC chondrogenesis pathway was studied by analyzing stage-specific gene expression using quantitative 'Real Time' reverse transcriptase polymerase chain reaction (qRT-PCR). Results showed that bovine MSCs underwent complete chondrogenesis; the initial stage was characterized by expression of sox 9 messenger ribonucleic acid (mRNA), followed by high transcription of chondrocyte specific genes, collagen type II and IX, biglycan and cartilage oligomeric matrix protein, and the final prehypertrophic and/or hypertrophic stage was distinguished by increased expression of collagen type X. From day 7 to day 14 of differentiation increased mRNA expression of the transforming growth factors beta1 and beta2, basic fibroblast growth factor (FGF 2), bone morphogenic protein 6 (BMP 6), insulin-like growth factors 1, parathyroid hormone related peptide and indian hedgehog (Ihh) were detected. These results suggest that these well know chondrogenic growth factors may play a role in bovine chondrogenesis in autocrine and/or paracrine manner. On day 21 of the culture, FGF 2, BMP 6 and Ihh were highly expressed, compared to cells cultured in monolayer manner, which suggests a possible function in maintaining the terminal stage of differentiation. This data extends our knowledge about the unusual species-specific bovine MSC chondrogenesis, allowing us to define the phenotype of the differentiated cells. Furthermore, this study contributes to our in understanding of known chondrogenic-growth factors in autocrine and/or paracrine manner playing a role in the spontaneous differentiation.
اظهر المزيد [+] اقل [-]Single-step reverse transcriptase-polymerase chain reaction for detection of borna disease virus RNA in vitro and in vivo
1999
Mizutani, T. (Hokkaido Univ., Sapporo (Japan)) | Ogino, M. | Nishino, Y. | Kimura, T. | Inagaki, H. | Hayasaka, D. | Kariwa, H. | Takashima, I.
There are few copies of Borna disease virus (BDV) genome in peripheral blood mononuclear cells and no reliable standard reverse transcriptase-polymerase chain reaction (RT-PCR) method for the detection of BDV RNA, which is both highly sensitive and free of contamination. Single-step RT-PCR, in which both reverse transcription and amplification by Taq DNA polymerase work efficiently in a single buffer, was applied to detect the p24 region of BDV RNA in vitro and in vivo. Using in vitro synthesized RNA, it was demonstrated that at least 100 copies of BDV RNA could be detected and the sensitivity and specificity were nearly equal to those obtained by RT-nested PCR. We could detect BDV RNA from more than 1 pg of cellular RNA obtained from BDV-persistently infected MDCK cells. Furthermore, this method was successfully performed on brain specimens obtained from a BDV-infected rat at 11 weeks post-inoculation. This single-step RT-PCR method will be convenient for detecting limited amounts of BDV RNA in various cells and tissue samples
اظهر المزيد [+] اقل [-]