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121.
This study was conducted to clarify the relationships among immunoglobulin (Ig)M, IgG, IgA, β‐carotene, vitamin A and α‐tocopherol contents in colostrum of 24 Japanese Black multiparous cows in order to evaluate the role of IgM on colostral IgG and IgA production. Compared with colostral IgG, colostral IgM and IgA were very low but varied widely. There was positive correlation between colostral IgM and IgG, but colostral IgM was not related with colostral IgA. There was no relationship between colostral IgM and age of cows, although colostral IgG was increased with aging. There were positive correlations among colostral β‐carotene, vitamin A and α‐tocopherol and these vitamins were positively correlated with colostral IgM and IgG. These results indicate that fat‐soluble vitamins may affect colostral IgG and IgM in cows and colostral IgG increases with the increase of colostral IgM.  相似文献   
122.
Diabetes mellitus (DM) and obesity are associated with neurodegenerative diseases such as Alzheimer’s disease and psychiatric disorders such as major depression. In this study, we investigated pathophysiological changes in the brains of female Spontaneously Diabetic Torii (SDT) fatty rats with diabetes and obesity. Brains of Sprague-Dawley (SD), SDT and SDT fatty rats were collected at 58 weeks of age. The parietal cortical thickness was measured and the number of pyramidal cells in the hippocampal cornu ammonis 1 and 3 (CA1 and CA3) and the number of granule cells in the dentate gyrus (DG) regions were counted. The area of glial fibrillary acidic protein (GFAP) positivity in CA1, CA3 and DG regions were measured. The parietal cortical thickness and the number of cells in CA3 and DG regions of SDT and SDT fatty rats did not show obvious changes. On the other hand, in the CA1 region, the number of cells in SDT rats and SDT fatty rats was significantly lower than that in SD rats, and that in SDT fatty rats was significantly lower than that in SDT rats. The GFAP-positive area in SDT fatty rats was significantly reduced compared to that in SD rats only in the DG region. Preliminarily result showed that the expression of S100a9, an inflammation-related gene, was increased in the brains of SDT fatty rats. These results suggest that female SDT fatty rat may exhibit central nervous system diseases due to obesity and DM.  相似文献   
123.
Alginase was purified from Gracilibacillus A7 and evaluated for its ability to produce elicitor-active oligosaccharides. The optimum conditions for the alginase reaction are as follows: temperature, 40 °C; pH, 8.0; alginate content, 0.3-0.7%; and the presence of Na(+) and Mg(2+) metal ions. The degree of polymerization (DP) decreased as the reaction time of the alginase progressed, achieving values of 5.4 and 3.3 after 240 and 300 min, respectively. The relative root length (RRL) of the Brassica campestris L. increased with the addition of oligosaccharides with reduced DP values. The oligosaccharides with lower DP values are effective in reducing the effect of salt stress on the activity of the superoxide dismutase (SOD) and guaiacol peroxidase (POD), and oligosaccharides with moderate DP values can reduce the increase in lipid peroxidation activities (as malondialdehyde content) induced by salt stress. These results suggest that oligosaccharides may act as osmoprotective agents during the plant germination process.  相似文献   
124.
Pemphigus is an autoimmune blistering disease characterized by lesions on the skin and mucous membranes. To date, no spontaneous cases of this disease have been reported in cynomolgus monkeys. This report describes the histopathological characteristics of spontaneous pemphigus in a cynomolgus monkey. Macroscopically, redness and scaling with pruritus were observed on the skin of the entire body. Histopathologically, the epidermis showed intercellular edema, and eosinophils and mononuclear cells infiltrated the epidermis. There was no obvious acantholysis in the epidermis. The perivascular area showed edema, and eosinophils and mononuclear cells infiltrated the vessels in the dermis. Immunohistochemically, the intercellular area in the epidermis was positive for Immunoglobulin G and Complement component 3. Serologically, anti-desmoglein 1 and desmoglein 3 antibodies in the serum were negative. From these findings, this case was diagnosed as an autoimmune skin disease, suspected to be pemphigus, and concluded as lesions being similar to those in human “pemphigus herpetiformis”.  相似文献   
125.
Environmental sex reversal (ESR) occurs when extreme environmental factors overpower predetermined sexual development. Scientific theory is beginning to acknowledge the potential roles of sex‐reversed individuals in influencing population dynamics and driving the evolution of sex‐determination mechanisms. ESR is a phenomenon that has been widely observed in fish and can be induced by exposing individuals to exogenous hormones. However, reports of the susceptibility of fish to hormonally induced ESR vary greatly – a concept we termed ‘inducibility’. It has been suggested that variation in inducibility can be attributed to biological differences among species of different taxonomic groups (i.e. phylogenetic effects are present). Here, we provide the first quantitative test of this theory, which was achieved by combining published data with phylogenetic trees, using phylogenetically controlled comparative analysis. Our results confirm that a great amount of variation exists in the reported inducibility of fish. However, species and taxonomic relationships were responsible for trivial portions of variation. Rather, we found that sampling (measurement) errors in combination with methodological differences across studies accounted for much more variation in inducibility than taxonomy did. Given that our analysis contains representatives from over 25% of all teleost orders, we conclude that inducibility is not a taxonomically constrained trait in teleosts. Therefore, we suggest that the sex‐determination mechanisms of most fish are uniformly plastic. Further, we propose that ESR occurs relatively regularly over evolutionary time in many teleost species, playing a vital role in the maintenance of homomorphic sex chromosomes in this taxonomic group.  相似文献   
126.
Pasteurella multocida, serovar A: 3, selected by pathogenicity in mice from among 10 strains isolated from pneumonic lesions of calves, was adjusted to 10(7), 10(8) and 10(10) colony-forming units (CFU), and inoculated intratracheally into four calves. All calves showed pyrexia and had lungs with congestion and hepatization. Inoculation with 10(10) CFU of bacteria produced respiratory symptoms and abscesses in lungs. This information will aid elucidation of the pathogenicity of P. multocida and the development of vaccines.  相似文献   
127.
Tacrolimus was reported to have no antifungal activity against dermatophytes, but it might show a synergistic fungicidal activity with azoles against dermatophytes as in the case of pathogenic yeasts. Therefore, we examined the antifungal activity of tacrolimus combined with itraconazole (ITZ) against five strains of Trichophyton mentagrophytes by measuring cell growth and performing MIC (minimum inhibitory concentration) testing. The mean colony diameter of T. mentagrophytes on 1/10 diluted Sabouraud dextrose agar (dSDA) with tacrolimus combined with ITZ was significantly shorter than that on dSDA with tacrolimus or ITZ. MICs of tacrolimus, ITZ, and tacrolimus combined with ITZ against T. mentagrophytes were determined, respectively. The results revealed a synergistic activity of tacrolimus in combination with ITZ against T. mentagrophytes.  相似文献   
128.
The present study was conducted to examine the developmental potential to offspring of rat embryos cultured from 1-cell to morula/blastocyst stage. Pronuclear zygotes from Wistar x Wistar or (SD x DA) x Wistar strains were cultured in modified rat 1-cell embryo culture medium (mR1ECM) for 96 h in 5% CO(2) in air at 37 C. The proportion of the 3-way cross hybrid zygotes developing into morula/blastocyst stage (74%) was higher than that of the Wistar zygotes (66%). Day-5 morulae/blastocysts developed in vitro were transferred into Day-3 or -4 pseudopregnant recipients of Wistar or SD x DA strain. The transfer of cultured embryos resulted in the birth of offspring at 13-59%, while that of non-cultured control blastocysts showed birth rates of 35-65%. The best offspring rate of cultured embryos (59%) was obtained when the hybrid 1-cell zygotes were cultured in mR1ECM medium and transferred into the 2-days earlier uteri of SD x DA recipients. These results suggest that genetic background of recipients as well as donors is a possible factor affecting full-term development of rat morulae/blastocysts derived from 1-cell stage zygotes cultured in vitro.  相似文献   
129.
To date, production of cloned rats by somatic cell nuclear transfer (NT) has not yet been successful. Inducing premature chromosome condensation (PCC) of injected cell nuclei in recipient cytoplasm is considered essential for successful mouse cloning by the Honolulu method. In the present study, some factors affecting PCC of rat cumulus cell nuclei injected into rat oocytes were examined. Wistar female rats (young: 4 to 5-week-old, mature: > or =10-week-old) were superovulated by injections of eCG and hCG, and oocytes recovered 14 or 17 h after hCG injection were received with cumulus cell nuclei using piezo-driven micromanipulator. When the oocytes were recovered 14 h post-hCG injection from young rats and the nuclear injection into oocytes was completed within 45 min, PCC was observed in 44-49% of NT oocytes. In the case of oocytes from mature rats, PCC occurred in 11-19% of the NT oocytes. Oocytes recovered 17 h post-hCG injection did not support PCC of the injected nuclei (0-7%) regardless of the donor age. Treatment of oocytes with a neutral cysteine protease inhibitor, N-acetylleucylleucylnorleucinal, slightly increased the incidence of PCC (48 vs 37%). Comparison of rat strains for oocyte donors indicated that proportions of NT oocytes undergoing PCC in Wistar and LEW oocytes (41-46%) were higher than those in Donryu and F344 oocytes (17-25%). Thus, ability of rat oocytes to promote PCC of the injected nuclei is dependent on the characteristics of oocytes, such as age or strain of donor rats, and timing of oocyte recovery.  相似文献   
130.
Defective appearances, including white spotting (WS), tongue defect (TD), and nipple defect (ND), in Japanese Black cattle potentially lead to economic losses to farmers in Japan. We estimated genetic parameters of defective appearances using 553,433 records of Japanese Black heifer calves housed in the Kagoshima Prefecture. Variance and covariance were estimated using the Gibbs sampling algorithm. The estimated heritability ranged from 0.29 for TD to 0.76 for WS. Percent breeding value (%BV) estimates indicated high variation in WS and ND among sires, reflecting higher heritability. Furthermore, there was a positive linear relationship between the %BV estimate of a sire and the mean incidence rate of each defect in his female offsprings. TD was positively associated with other defects. Therefore, genetic factors strongly affect the incidence of defective appearances in Japanese Black cattle.  相似文献   
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