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981.
982.
The vagus nerve is one route of transneural invasion for intranasally inoculated influenza a virus in mice 总被引:3,自引:0,他引:3
Matsuda K Park CH Sunden Y Kimura T Ochiai K Kida H Umemura T 《Veterinary pathology》2004,41(2):101-107
Intranasally inoculated neurotropic influenza viruses in mice infect not only the respiratory tract but also the central nervous system (CNS), mainly the brain stem. Previous studies suggested that the route of invasion of virus into the CNS was via the peripheral nervous system, especially the vagus nerve. To evaluate the transvagal transmission of the virus, we intranasally inoculated unilaterally vagectomized mice with a virulent influenza virus (strain 24a5b) and examined the distribution of the viral protein and genome by immunohistochemistry and in situ hybridization over time. An asymmetric distribution of viral antigens was observed between vagal (nodose) ganglia: viral antigen was detected in the vagal ganglion of the vagectomized side 2 days later than in the vagal ganglion of the intact side. The virus was apparently transported from the respiratory mucosa to the CNS directly and decussately via the vagus nerve and centrifugally to the vagal ganglion of the vagectomized side. The results of this study, thus, demonstrate that neurotropic influenza virus travels to the CNS mainly via the vagus nerve. 相似文献
983.
Bae JS Jang KH Park SC Jin HK 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(1):111-114
The effects of topical administration of polysaccharides isolated from fungus, Phellinus gilvus (PG) on the healing of rat dermal wounds were assessed. In 10 Sprague-Dawley (SD) rats, six 6 mm diameter defects were made with a punch biopsy appliance. After 24 hr, test substances were applied to the defects twice a day: 0.025, 0.25, and 2.5% polysaccharides from PG (PG0.025, 0.25, and 2.5 groups), Madecassol ointment (MC group), aqueous gel (AG group) and no treatment (control group). Six days postoperatively, the contraction and reepithelialization of the wound surface were assessed. Wound diameter was significantly reduced in all PG groups (P<0.05). Complete epithelialization and macrophages were noted in the PG0.25 group, as compared to the control group. We conclude that polysaccharides isolated from PG have significant dermal wound healing effects, and this investigation suggests the potential clinical application of PG as a wound healing agent. 相似文献
984.
Jeong JH Kim GY Yoon SS Park SJ Kim YJ Sung CM Jang OJ Shin SS Koh HB Lee BJ Lee CY Kang MI Kim HJ Park NY Cho KO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(2):187-189
Although winter dysentery (WD) has been suspected to occur frequently in Korea, to date the exact epidemiology of WD has remained unknown. Therefore, we investigated the causative agents of WD by using electron microscopy, ELISA, RT-PCR, and nested PCR from 97 fecal samples of 32 WD-affected herds collected from 8 provinces during 2002-2004. The bovine coronavirus (BoCV) was consistently detected in all herds with WD. Of other pathogens, only coccidian oocyts were inconsistently but concurrently detected with BoCV. Ten isolates were identified as BoCV by immune electron microscope, immunofluorescent test and ELISA with antiserum to BoCV, and RT-PCR. From these results, it is concluded that WD caused by BoCV occurred in relatively high frequency and was widespread in Korea. The results provide important epidemiological data for the control and establishment of a surveillance system for WD in Korea. 相似文献
985.
Jeong WI Jeong DH Do SH Kim YK Park HY Kwon OD Kim TH Jeong KS 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(3):235-242
To date, the majority of research on hypercholesterolemia has focused on the effects of a high cholesterol diet on atherosclerosis and coronary heart disease. The toxic effects of cholesterol on the liver and the relationship between the intake of a high cholesterol diet and hepatic fibrosis, however, have not been investigated clearly or histopathologically. Male Wistar rats were fed a diet supplemented with 1.0% cholesterol and 0.3% sodium cholate for 12 weeks. Rats were sacrificed and analyzed via blood biochemistry, traditional microscopy and immunohistochemistry. Following the feeding of this diet, the rates of aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase and total cholesterol in the rats were elevated consistently from week 3 and throughout the remainder of the experiment. From microscopic observation, hepatic necrosis, macrophage infiltration and steatosis increased markedly throughout the experiment. Hepatic fibrosis and myofibroblast proliferation were detected at weeks 9 and 12. Mast cell appearance was proportional to the degree of hepatic damage. These findings suggest that hepatic fibrosis is inducible by a high cholesterol diet and is likely the result of the interaction between several different cell types (i.e., macrophages, myofibroblasts, and mast cells) in an inflammatory milieu. Hypercholesterolemia should be considered as a risk factor for hepatic fibrosis as well as atherosclerosis and coronary artery disease. 相似文献
986.
Role of gap junctional intercellular communication (GJIC) through p38 and ERK1/2 pathway in the differentiation of rat neuronal stem cells 总被引:4,自引:0,他引:4
Yang SR Cho SD Ahn NS Jung JW Park JS Jo EH Hwang JW Jung JY Kim TY Yoon BS Lee BH Kang KS Lee YS 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(3):291-294
Gap junctional intercellular communications (GJIC) contributes to neural function in development and differentiation of CNS. In this study, we have investigated the expression of GJIC during the differentiation of neuronal stem cells and 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced neuronal stem cell-derived cells from rat brain. During neuronal stem cell differentiation, expressions of Cx43 and 32 were increased for the duration of 72 hr, however the effect were decreased on the 7d. In the neuronal stem cell-derived cells, pretreatments with p38 MAP kinase inhibitor, SB203580, and MEK inhibitor, PD98059, could protect GJIC against TPA-induced inhibition of GJIC. Our data suggest that GJIC plays an important role during neuronal stem cell differentiation, and ERK1/2 and p38 MAP kinase signaling pathway may be closely related functionally to regulate gap junction in rat neuronal stem cell-derived cells. 相似文献
987.
Kim SS Lee RD Lim KJ Kwack SJ Rhee GS Seok JH Lee GS An BS Jeung EB Park KL 《The Journal of reproduction and development》2005,51(2):201-210
Many environmental chemicals including pesticides have been reported to possess hormonal activities, and thus are classified as endocrine disruptors. Permethrin, a synthetic pyrethroid insecticide, is used worldwide, which provides potential environmental exposure. However, relatively few studies have reported on hormonal activities, particularly estrogenic and androgenic activities of permethrin, and the results of these studies are in some respects contradictory. Therefore, this study investigated the potential estrogenic and androgenic activities of permethrin in vitro and in vivo. We conducted an uterine Calbindin-D9k (CaBP-9k) gene expression assay and an uterotrophic assay for estrogenic activity, and a Hershberger assay for androgenic activity. The CaBP-9k gene, one of the intracellular calcium binding proteins, is estrogen-responsive in the uterus. The rat uterotrophic and Hershberger assays are generally used as in vivo short-term screening assays for detecting the estrogenic and androgenic activities of chemicals, although these assays are still being validated by the Organization for Economic Cooperation and Development (OECD). Northern blot analysis showed the induction of uterine CaBP-9k mRNA level in response to permethrin as well as co-administration of permethrin with E2. In the uterotrophic assay using 18-day-old female rats, subcutaneous treatments with permethrin (10 to 800 mg/kg) for three days increased relative uterine wet weights, and E2-induced uterine weights. These effects were statistically significant at 800 and 200 mg/kg, respectively. Moreover, permethrin-induced uterine weights were inhibited by the co-administration of ICI 182,780, an antiestrogen. In the Hershberger assay, the administration of permethrin orally to testosterone propionate-treated castrated male rats led to statistically significant reductions in androgen-dependent sex accessory tissue (ventral prostate, seminal vesicles, levator ani and bulbocavernosus muscles, Cowper's gland and glans penis) weights at all doses tested (10, 50 and 100 mg/kg). These results suggest that permethrin might have estrogen-like effects on female rats, but antiandrogen-like effects on males. 相似文献
988.
989.
990.
Joon-young Kim Hyun-jung Han Hun-young Yun Bora Lee Ha-young Jang Ki-dong Eom Hee-myung Park Soon-wuk Jeong 《Journal of veterinary science (Suw?n-si, Korea)》2008,9(1):91-93
To evaluate the potential utility of a self-expandable intratracheal nitinol stent with flared ends for the treatment of tracheal collapse in dogs, endotracheal stenting therapy was performed under fluoroscopic guidance in four dogs with severe tracheal collapse. During the 4 to 7 month follow-up, after stent implantation, clinical signs, including dyspnea and respiratory distress, dramatically improved in all dogs. The radiographs showed that the implanted stents improved the tracheal collapse, and there were no side effects such as collapse, shortening or migration of the stents. In conclusion, the self-expandable intratracheal nitinol stents provided adequate stability to the trachea and were effective for attenuating the clinical signs associated with severe tracheal collapse. 相似文献