Уточнить поиск
Результаты 101-110 из 269
Pathological evaluation of renal changes induced by multiple nephropathogenic facotrs in SPF chickens
1999
Kang, K.I. | Hahn, T.W. | Han, J.H. (Kangwon National University, Chuncheon (Korea Republic). Department of Veterinary Medicine) | Mo, I.P. | Kwon, Y.K. | Kang, M.S. (National Veterinary Research and Quarantine, Anyang (Korea Republic).)
Renal failure is one of the main causes of economic impacts in the poultry industry and complex syndrome with different severity of clinical signs caused by multiple nephropathogenic factors such as infectious bronchitis viral infection and excess salt and calcium in diet. To evaluate the correlation between severity of renal failure and the causative nephropathogenic factors, one-day-old specific patogen free chicks were treated with either single causative factor or multiple causative factors described as above. Each group was designed as control for non-treated control, IB for infectious bronchitis virus (IB virus) infectio, IBHNa for IB virus infection with high diet salt, IBHCa for IB virus infectio with high diet calcium, IBHNC for IB virus infection with high diet salt and calcium, HNa for high diet salt, HCa for high diet calcium and HNC for high diet salt and calcium. Chickens were inoculated with IB virus at 1-day-old and remained on their respective diets until 21 day of age. The high dietary salt feeding groups such as IBHNa, IBHNC, HNa, HNC increased water intake, watery diarrhea, general subcutaneous edema and the high dietary calcium feeding groups such as IBHCa and IBHNC showed severe visceral gout. Two more than treated groups caused high mortality in comparison with the single treated groups. In virus exposure significantly increased urate deposition and lymphocytic interstitial nephritis. Espcecially urate deposition dramatically increased when excess diet calcium was combined together. In excess diet salt treated groups enlarged edematous kidneys were observed and hypertrophy of glomeruli were showed. These results suggest that IB virus enhanced the incidence and severity on chicken renal failure clearly related to the quantity of salt and calcium.
Показать больше [+] Меньше [-]An assessment of statistical errors in articles in the Korean journal of veterinary research
1999
Park, S.I. (Seoul National University, Seoul (Korea Republic). Department of Internal Medicine, College of Veterinary Medicine)
The purpose of this study is to assess the suitability of the statistical techniques employed in papers published in the Korean Journal of Veterinary Research from March 1997 to March 1999 and it is hoped that the critical assessment may be of help to other researchers preparing their works for publication. Of the 246 original papers 94 were inclluded in the analysis. of 62 papers with the measure of central location and dispersion of data 34(54.8%) used them correctly:9 (39.1%) of 23 for t-test; 1 (33.3%) of 3 for correlation analysis; 7 (43.8%) of 16 for analysis of variance (ANOVA); 5 (62.5%) of 8 for chi-square test; 44 (71%) of 62 for description of p-value. A number of papers employed ANOVA did not perform subsequent analysis of multiple comparison. Compared to the results of others, relatively higher proportion of papers in the present study was evaluated as appropriate analysis. The reason is that papers described insufficiently on the study design were not included, and evaluation items were restricted to the cases violated seriously ingerent assumptions for each statistical technique. Statistical misuse or abuse appeared in the study is due to lack of knowledge on statistics and short of its importance for improvement the quality of paper. Because an inappropriate analysis can lead the readers to misunderatand on findings, observed statistical analyses must be valid,and correctly undertaken. It is suggested that more intensive statistical refereeing are needed,and the communication should be allowed for the controversial points.
Показать больше [+] Меньше [-]Effects of substance P on nicotine-induced intracellular Ca2+ dynamics in bovine adrenal chromaffin cells
1999
Suzuki, S. (Hokkaido Univ., Sapporo (Japan)) | Habara, Y. | Kanno, T.
Substance P (SP) is colocalized with ACh in splanchnic nerves that innervate into adrenal medulla and the peptide has been shown to inhibit nicotinic agonists-induced catecholamine secretion. To elucidate the effects of SP on cytosolic Ca(2+) dynamics, the present study was conducted using fura-2-loaded isolated bovine adrenal chromaffin cells. Stimulation of the cells with nicotine (10-100mu-M) produced a rapid rise of cytosolic Ca(2+) concentration ([Ca(2+)]i), the peak level of which increased in a dose-dependent manner, followed by a gradual decay. In the presence of 10mu-M SP, the dose-response relationship of the peak levels shifted downward. Quantitative analyses implied that SP inhibits the nicotine-induced Ca(2+) influx in a noncompetitive manner. Nicotinic acetylcholine receptor is composed of two major functional domains: an agonist-binding site and an ionophore or channel domain. Agonist binding activates ionophore / channel domain and causes mainly Na(+) influx. This Na(+) influx depolarizes the cell and activates voltage-dependent Ca(2+) channels. Based on this fact, the present results indicate that SP dose not block nicotine binding sites but interferes with other sites of nicotinic receptor / channel molecule, most probably a channel domain. It was suggested that SP colocalized with ACh in splanchnic nerves functions as a physiological modulator of catecholamine secretion by non-competitively suppressing ACh-induced cytosolic Ca(2+) dynamics in bovine a
Показать больше [+] Меньше [-]Evaluation of coproantigen diagnosis for natural Echinococcus multilocularis infection in red foxes [Vulpes vulpes]
1999
Morishima, Y. (Hokkaido Univ., Sapporo (Japan)) | Tsukada, H. | Nonaka, N. | Oku, Y. | Kamiya, M.
The validity of a coproantigen ELISA for Echinococcus multilocularis was evaluated by comparison of three diagnostic methods; autopsy, egg examination and the ELISA. Of 71 foxes, 39 were found to be infected with the cestode at autopsy. The overall mean of worm burdens was 3,451, but the number varied (1-34,522). The ELISA could detect 94.9% (37/39) of the worm positives and there were no false-positives. Two false-negatives were infected with 1 and 4 cestodes, whereas 3 cases with similar worm burdens (2, 4 and 6 worms) were diagnosed as positives. This indicates the detection limit of the assay may be equivalent to less than 10 (in the worm burden). On the other hand, egg examination showed low sensitivity (43.6%, 17/39). These results suggest the ELISA has a potential to replace for the conventional methods
Показать больше [+] Меньше [-]Antigenic and genetic analyses of H5 influenza viruses isolated from ducks [Anas platyrynchos] in Asia
1999
Imai, M. (Hokkaido Univ., Sapporo (Japan)) | Takada, A. | Okazaki, K. | Kida, H.
The hemagglutinin (HA) of six H5 influenza virus strains isolated from ducks in Japan and China in 1976 to 1996 were analyzed antigenically and genetically. Antigenic analysis using a panel of monoclonal antibodies revealed that the HA of H5 influenza viruses isolated from ducks are antigenically closely related to each other. Phylogenetic analysis indicates that the isolates from ducks in Hokkaido were derived from an ancestor common with the highly pathogenic isolates from chickens and human
Показать больше [+] Меньше [-]Protective effects of intranasal vaccination with plasmid encoding pseudorabies virus glycoprotein B in mice
1999
Takada, A. (Hokkaido Univ., Sapporo (Japan)) | Okazaki, K. | Kida, H.
Intranasal administration of plasmid DNA encoding glycoprotein B of pseudorabies virus into mice induced both serum and secretory antibody responses. These mice resisted intranasal challenge with lethal dose of the virus, but did not intraperitoneal challenge. On the other hand, intramuscular injection of the plasmid induced less secretory and higher serum antibody responses than those of intranasally vaccinated mice. None of them was protected from virus challenge. The present results suggest that administration of plasmid DNA encoding glycoprotein B by respiratory mucosal route generates local secretory antibodies which serve to protect animals from pseudorabies virus infection
Показать больше [+] Меньше [-]Effects of concurrent exposure to 3-methylcholanthrene and vitamin A on fetal development in rats
1999
Khlood, El.B.M. (Hokkaido Univ., Sapporo (Japan)) | Miyoshi, H. | Iwata, H. | Kazusaka, A. | Kon, Y. | Hadid, A.H.A. | Moustafe, El.K. | Ghonim, M.H. | Fujita, S.
To investigate the effect of the environmental pollutants, polycyclic aromatic hydrocarbons (PAHs), on retinoic acid-induced teratogenesis, all-trans-retinoic acid (RA) dissolved in corn oil (120 mg/kg) was administered orally to pregnant rats at the 11th day of gestation with and without the prior intraperitoneal treatment with 10 mg/kg 3-methylcholanthrene (3-MC) for 3 days. Dams were killed on the 20th day of pregnancy. The examinations of fetuses revealed that 3-MC barely enough to cause induction of P-450 in pregnant dams had profound embryo-toxic effects: the fetal resorption amounted to - 60% of total number of implantations. The fetuses survived weighed less than the control fetuses. All of RA-treated mothers had fetuses with abnormalities, and the main malformations were absence of tail (100%), caudal and sacral malformations (100%), and cleft palate (42%). Pregnant dams received both 3-MC and RA had a reduced severeness of tail anomaly (33%), while the rest, 67%, had short vestigial tail. Caudal and sacral malformations were detected but at a milder degree. We did not observe cleft palate in this group. The concurrent treatment of dams with 3-MC and RA led to an increased inducibility of cytochrome P-450 and subsequently, CYP1A1 dependent enzyme activity higher than those observed after the injection of 3-MC alone. UDP-glucuronyltransferase activity was also markedly induced in concurrent 3-MC and RA group higher than that in 3-MC alone. We suggest that the induction of P-450 and alteration of metabolic enzyme activities may play an important role in reducing the teratogenic potency of RA. However, RA-treatment did not retard the embryo-toxic effect of 3-MC but rather potentiated
Показать больше [+] Меньше [-]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
Показать больше [+] Меньше [-]Characterization of proteolytic enzymes expressed in the midgut of Haemaphysalis longicornis
1999
Mulenga, A. (Hokkaido Univ., Sapporo (Japan)) | Sugimoto, C. | Onuma, M.
The proteolytic activities present in midguts of both fed and unfed Haemaphysalis longicornis were assessed by using the gelatin-substrate gel electrophoresis and inhibitor sensitivity analyses. Three predominant (116, 48 and 40 kDa) and two weak (55 and 60 kDa) proteinase bands were commonly expressed in both unfed and fed ticks, while a weak 80 kDa band was only present in fed ticks. Consistent with observations on other tick species, proteolytic activity against the gelatin substrate was observed only under acidic conditions. Inhibition studies against the gelatin substrate using a panel of inhibitors showed that the predominant proteolytic enzymes of 40 and 48 kDa molecular mass are cysteine proteinases. These results are discussed in the context of host vaccination as an alternative tick control method to the current use of chemical acaricides
Показать больше [+] Меньше [-]A comparison of serum biochemical changes in two breeds of sheep (Red Masai and Dorper) experimentally infected with Fasciola gigantica
1999
Waweru, J.G. | Kanyari, P.W.N. | Mwangi, D.M. | Ngatia, T.A. (Nairobi Univ. (Kenya). Dept. of Veterinary Pathology and Microbiology) | Nansen, P.