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1.
为了探究影响哺乳动物毛色的黑色素皮质受体-1基因(MC1R)和转录因子25基因(TCF25)与滩羊毛色的关系,本研究利用实时荧光定量PCR(qRT-PCR)技术,对15只不同毛色滩羊(纯白、褐斑、黑斑)皮肤组织中MC1R基因和TCF25基因的mRNA表达量进行研究。结果显示,MC1R基因和TCF25基因在3种不同毛色滩羊中均有表达。MC1R基因在不同毛色滩羊皮肤组织中表达量为黑斑>褐斑>纯白,其中黑斑组极显著高于纯白组(P<0.01),显著高于褐斑组(P<0.05),褐斑组显著高于纯白组(P<0.05);TCF25基因在不同毛色滩羊皮肤组织中表达量为纯白>褐斑>黑斑,组间差异不显著(P>0.05)。试验表明了目的基因表达量与滩羊毛色间的关系,为今后滩羊毛色选育与品种改良提供参考。 相似文献
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H. Titmarsh A.G. Gow S. Kilpatrick J. Sinclair T. Hill E. Milne A. Philbey J. Berry I. Handel R.J. Mellanby 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2015,29(6):1473-1478
Background
Dogs with a chronic enteropathy (CE) have a lower vitamin D status, than do healthy dogs. Vitamin D status has been associated with a negative clinical outcome in humans with inflammatory bowel disease.Objectives
To examine the relationship between serum 25 hydroxyvitamin D (25(OH)D) concentrations at diagnosis and clinical outcome in dogs with a CE.Animals
Forty‐one dogs diagnosed with CE admitted to the Royal Dick School of Veterinary Studies, Hospital for Small Animals between 2007 and 2013.Methods
Retrospective review. Serum 25(OH)D concentrations were compared between dogs which were alive at follow up or had died because of non‐CE‐related reasons (survivors) and dogs which died or were euthanized due to their CE (non‐survivors). A binary logistic regression analysis was performed to determine significant predictors of death in dogs with CE.Results
Serum concentrations of 25(OH)D at the time a CE was diagnosed were significantly lower in nonsurvivors (n = 15) (median nonsurvivors 4.36 ng/mL, interquartile range 1.6–17.0 ng/mL), median survivors (n = 26) (24.9 ng/mL interquartile range 15.63–39.45 ng/mL, P < .001). Serum 25(OH)D concentration was a significant predictor of death in dogs with CE (odds ratio 1.08 [95% CI 1.02–1.18)]).Conclusions
Serum 25(OH)D concentrations at diagnosis are predictive of outcome in dogs with CE. The role of vitamin D in the initiation and outcome of chronic enteropathies in dogs is deserving of further study. 相似文献4.
Vitamin D Status in Different Stages of Disease Severity in Dogs with Chronic Valvular Heart Disease 下载免费PDF全文
T. Osuga K. Nakamura T. Morita S.Y. Lim K. Nisa N. Yokoyama N. Sasaki K. Morishita H. Ohta M. Takiguchi 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2015,29(6):1518-1523
Background
In humans with heart disease, vitamin D deficiency is associated with disease progression and a poor prognosis. A recent study showed that serum 25‐hydroxyvitamin D [25(OH)D] concentration, the hallmark of vitamin D status, was lower in dogs with heart failure than in normal dogs, and a low concentration was associated with poor outcome in dogs with heart failure.Objectives
To elucidate the vitamin D status of dogs with chronic valvular heart disease (CVHD) at different stages of disease severity.Animals
Forty‐three client‐owned dogs with CVHD.Methods
In this cross‐sectional study, dogs were divided into 3 groups (14 dogs in Stage B1, 17 dogs in Stage B2, and 12 dogs in Stage C/D) according to ACVIM guidelines. Dogs underwent clinical examination including echocardiography. Serum 25(OH)D concentrations were measured in each dog.Results
Serum 25(OH)D concentration was significantly lower in Stage B2 (median, 33.2 nmol/L; range, 4.9–171.7 nmol/L) and C/D (13.1 nmol/L; 4.9–58.1 nmol/L) than in Stage B1 (52.5 nmol/L; 33.5–178.0 nmol/L) and was not significantly different between Stage B2 and Stage C/D. Among clinical variables, there were significant negative correlations between 25(OH)D concentration and both left atrial‐to‐aortic root ratio and left ventricular end‐diastolic diameter normalized for body weight.Conclusions and Clinical Importance
These results indicate that vitamin D status is associated with the degree of cardiac remodeling, and the serum 25(OH)D concentration begins to decrease before the onset of heart failure in dogs with CVHD. 相似文献5.
Feeding Solanum glaucophyllum to preparturient multiparous cows prevents postparturient hypocalcemia 下载免费PDF全文
Junichiro Ishii Akifumi Uramoto Yoshikazu Nagao Hisaya Goto 《Animal Science Journal》2015,86(10):869-877
Solanum glaucophyllum (SG) contains 1,25‐dihydroxyvitamin D3 (1,25‐(OH)2D3) glycosides. We investigated the effect of SG on hypocalcemia in cows. Serum levels of 1,25‐(OH)2D3, total calcium and phosphorus dose‐relatedly increased after feeding with SG, while serum magnesium and chloride levels fell (P < 0.05). We also performed an ethylenediaminetetraacetic acid (EDTA) infusion to induce artificial hypocalcemia. Cows that had been fed 4.0 mg/kg body weight of SG daily for 2 weeks had a higher serum concentration of total calcium at the end of EDTA infusion than those not fed SG (P < 0.05). In a field trial, multiparous cows were assigned to one of four groups: (1) no SG, (2) 1.3 g or (3) 2.6 g of SG daily from 14 days before the estimated calving day until 3 days after calving, or (4) a single feed of 35.75 g SG at 3 days before the estimated calving day. The concentrations of serum total calcium after the calving in each treatment group were (1) 7.4, (2) 7.9, (3) 8.0 and (4) 8.9 mg/dL and higher for (4) than for (1) (P < 0.05). The data suggests that feeding a high dose of SG before the calving may maintain higher concentrations of serum calcium after the calving. 相似文献
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为探究马传染性贫血病毒(EIAV)附属蛋白Rev负调控Tripartite motif-containing protein 5α(TRIM5α)介导的AP-1信号通路的机制,本研究将pEIAV-Rev-HA和pcDNA3.1质粒分别与含TRIM5α基因的质粒及pGL3-AP-1-Luc(AP-1报告质粒)共转染HEK 293T细胞,采用荧光素酶试验检测Rev对TRIM5α激活的AP-1信号通路的影响;将pEIAV-Rev-HA和pcDNA3.1质粒分别与含TAK1、TAB2、P38和c-Jun基因的质粒及pGL3-AP-1-Luc共转染HEK 293T细胞,采用荧光素酶试验检测Rev对TRIM5α下游转导分子(TAK1、TAB2、P38、c-Jun)激活的AP-1信号通路的影响;将pEIAV-Rev-HA和pcDNA3.1质粒分别与含TAK1、TAB2、P38基因的质粒共转染HEK293T细胞,利用western blot试验分别检测TAK1、TAB2、P38的表达水平;将pEIAV-Rev-HA和pcDNA3.1质粒分别与含P38基因的质粒共转染HEK 293T细胞后加入蛋白酶体抑制剂MG132,利用western blot检测P38蛋白的表达情况。结果显示,共转染EIAV-Rev-HA实验组中TRIM5α对AP-1的激活倍数为0.4,而共转染pcDNA3.1对照组中相应的激活倍数为26.0;共转染pEIAV-Rev-HA实验组中,TAK1、TAB2、P38和c-Jun对AP-1信号通路的激活倍数分别为7.7、0.1、0.6、9.8,而共转染pcDNA3.1对照组中对AP-1信号通路的激活倍数分别为60.0、1.5、6.3、12.0;转染pEIAV-Rev-HA+pP38-Flag组与转染pcDNA3.1+pP38-Flag组相比,前者P38蛋白的表达量显著降低;加入蛋白酶体抑制剂组则恢复了P38蛋白的表达。上述结果表明,EIAV Rev显著下调eqTRIM5α及其下游转导分子TAK1、TAB2、P38激活的AP-1信号通路,但不显著下调c-Jun激活的AP-1信号通路;EIAV Rev通过蛋白酶体途径降解P38蛋白的表达而抑制eqTRIM5α激活的AP-1信号通路。本研究结果为理解EIAV与宿主蛋白相互作用提供参考依据。 相似文献
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为研究不同剂量25羟基维生素D3[25(OH)VD3]对断奶前犊牛血液水平、抗氧化能力和免疫功能的影响,选取18 头健康状况良好的新生荷斯坦犊牛,随机分成3 组,每组6 头进行为期56 天的饲养试验。分为对照组[不添加25(OH)VD3]、低剂量组[25(OH)VD3添加量6 000 IU/头·天]和高剂量组[25(OH)VD3添加量12 000 IU/头·天]。结果表明,与对照组相比,随着25(OH)VD3添加剂量增加,血浆生长激素、胰岛素样生长因子-1、过氧化氢酶、超氧化物歧化酶、总抗氧化能力以及免疫球蛋白G(IgG)含量显著增加(P<0.05),而丙二醛含量随剂量增加而存在降低趋势(P=0.079)。与对照组和低剂量组相比,高剂量组血浆免疫球蛋白A(IgA)含量有增加趋势(P=0.059)。综上所述,断奶前犊牛饲喂高剂量25(OH)VD3有利于促进体内生长激素和胰岛素样生长因子-1分泌,可提高犊牛抗氧化能力,增强免疫功能。 相似文献
9.
CDC25A, TSSK3 and P53 expressionsin vitro in cultured sertoli cells after FSH treatment were studied in order to provide some data for further researches of spermatogenesis. Different concentrations of... 相似文献
10.
WANG Jun CHANG Li-hong LI Xia CHEN Xian-zhen WU Xi-fu WANG Zhi-yuan HUANG Zi-zhen HUANG Jian-cong ZHANG Ge-hua 《园艺学报》2017,33(9):1611-1618
AIM: To investigate the mechanism of the radiosensitizing effect of maximum non-cytotoxic doses of tetrandrine (Tet) on nasopharyngeal carcinoma cell lines CNE1 and CNE2.METHODS: The cells were treated with ma-ximum non-cytotoxic doses of Tet (for CNE1 cells at 1.5 μmol/L and for CNE2 cells at 1.8 μmol/L), irradiation at 4 Gy, or combination of irradiation and maximum non-cytotoxic doses of Tet. The cell cycle distribution was analyzed by flow cytometry. The protein levels of γ-H2AX, cleaved caspase-3, p-CDC25C, CDK1, p-CDK1, cyclin B1, ERK and p-ERK were determined by Western blot.RESULTS: The expression of γ-H2AX was increased in CNE1 cells and CNE2 cells after combined treatment with irradiation and maximum non-cytotoxic doses of Tet. The percentages of CNE1 cells and CNE2 cells at G2/M phase in irradiation group were (18.09±0.42)% and (18.48±1.32)%, respectively, which were decreased to (15.88±1.04)% and (13.80±0.82)% in combined treatment group, respectively (P<0.05). Combined treatment enhanced the increase in the protein level of cleaved caspase-3 caused by irradiation. The protein levels of p-CDC25C and p-CDK1 were increased in a dose-dependent manner by Tet treatment (P<0.05), while the expression of CDK1 showed no difference among different doses of Tet treatments. The protein levels of p-CDC25C, p-CDK1 and CDK1 showed no difference after the treatment with maximum non-cytotoxic doses of Tet. The combined treatment with irradiation and the maximum non-cytotoxic doses of Tet decreased the protein levels of p-CDC25C and p-CDK1 (P<0.05), increased the expression of cyclin B1, and had no influence on the expression of CDK1 (P<0.05). The combined treatment resulted in an increase in the protein level of p-ERK1 (P<0.05).CONCLUSION: The maximum non-cytotoxic doses of Tet enhance the DNA damage and apoptosis in CNE1 cells and CNE2 cells caused by irradiation, and the mechanism might be associated with ending of G2/M arrest via activation of ERK/CDC25C/CDK1/cyclin B1 pathways. 相似文献