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991.
992.
Effect of short‐chain fatty acids on triacylglycerol accumulation,lipid droplet formation and lipogenic gene expression in goat mammary epithelial cells 下载免费PDF全文
Yuting Sun Jun Luo Jiangjiang Zhu Hengbo Shi Jun Li Siyuan Qiu Ping Wang Juan J. Loor 《Animal Science Journal》2016,87(2):242-249
Short‐chain fatty acids (SCFAs) are the major energy sources for ruminants and are known to regulate various physiological functions in other species. However, their roles in ruminant milk fat metabolism are still unclear. In this study, goat mammary gland epithelial cells (GMECs) were treated with 3 mmol/L acetate, propionate or butyrate for 24 h to assess their effects on lipogenesis. Data revealed that the content of triacylglycerol (TAG) and lipid droplet formation were significantly stimulated by propionate and butyrate. The expression of FABP3, SCD1, PPARG, SREBP1, DGAT1, AGPAT6 and ADRP were upregulated by propionate and butyrate treatment. In contrast, the messenger RNA (mRNA) expression of FASN and LXRα was not affected by propionate, but reduced by butyrate. Acetate had no obvious effect on the content of TAG and lipid droplets but increased the mRNA expression of SCD1 and FABP3 in GMECs. Additionally, it was observed that propionate significantly increased the relative content of mono‐unsaturated fatty acids (C18:1 and C16:1) at the expense of decreased saturated fatty acids (C16:0 and C18:0). Butyrate and acetate had no significant effect on fatty acid composition. Overall, the results from this work help enhance our understanding of the regulatory role of SCFAs on goat mammary cell lipid metabolism. 相似文献
993.
994.
Thayne Montague Edward W. Hellman David Appel Michael Krawitzky 《International Journal of Fruit Science》2016,16(2):135-149
An objective of this study was to investigate rooting success of grape cuttings propagated from vines symptomatic of Pierce’s disease. Additional objectives were to assess if rooted cuttings could survive and produce viable plants, and determine if Xylella fastidiosa (causal agent of Pierce’s disease) could be found in rooted cuttings. In Jan. 2008, cuttings were taken from symptomatic and asymptomatic ‘Merlot’ and ‘Cabernet Sauvignon’ grapevines growing in the Hill Country and Gulf Coast regions of Texas. Six weeks after cuttings were propagated, each cutting was uprooted and evaluated for rooting and infection parameters. Cuttings were then planted in containers and held in the greenhouse to evaluate survivability. To confirm the presence of X. fastidiosa, propagated cuttings were tested by real-time polymerase chain reaction. Data indicate several rooted cuttings tested positive for X. fastidiosa and appeared viable and healthy. Therefore, vines infected with X. fastidiosa have the ability to produce asexually propagated cuttings, and potentially contaminate non-infected vineyards. 相似文献
995.
AIM: To observe the effect of botulinum neurotoxin type A heavy chain (BoNT/A HC) on the pattern of spinal protein expression by intrathecal injection after spinal cord injury in rats, and to explore the role of BoNT/A HC intervention in spinal protein expression and some of its mechanisms in nerve regeneration after injury. METHODS: The model of unilateral lumbar spinal cord injury was established. The effects of BoNT/A HC intervention at different doses (2 μg, 4 μg, 6 μg and 8 μg) on the general pattern of protein expression in the spinal cord tissues at the injury site and the cranial part adjacent to the injury site was measured and evaluated by SDS-PAGE and Coomassie brilliant blue staining first, and then by two-dimensional SDS-PAGE. RESULTS: The histological structure of the ipsilateral side of lumbar spinal cord showed obvious destruction and degradation, mainly affecting both gray and white matter of the left side of the cord. The result of SDS-PAGE with Coomassie brilliant blue staining from injured spinal cord tissue displayed that the expression of some proteins after one-time BoNT/A HC treatment appeared obviously different from that without BoNT/A HC treatment. Moreover, the pattern of the protein expression affected by BoNT/A HC was similar to that of the normal spinal cord. The more detail information from two-dimensional SDS-PAGE indicated that more than 10 proteins with different molecular weight and isoelectronic points were differentially expressed at day 2 and day 20 after local injection of 6 μg BoNT/A HC. This altered expression actually appeared a tendency toward the pattern shown in normal group. CONCLUSION: The immediate application of BoNT/A HC at the injury site after unilateral lumbar spinal cord injury is able to affect the pattern of local protein expression. The altered protein expression by injury could be reversed back to normal or approximately normal by local BoNT/A HC administration. 相似文献
996.
光生物素标记的口蹄疫病毒cDNA探针的制备及其对口蹄疫病毒RNA检测的试验研究 总被引:1,自引:0,他引:1
本文首次报道了利用pF1034质粒制备FMDV O型特异性探针,并通过PCR反应扩增FMDO_1K株病毒基因组的第2962位与3071位之间共110bp序列,制备了能检测O型、A型和亚洲I型FMDV RNA的群(组)特异性探针。用硝酸纤维素膜斑点杂交试验表明,二者均能检测出10pg水平的O_9K毒株的纯RNA;但前者只与O型FMDV RNA杂交,与A型及亚洲I型FMDV RNA无交叉杂交现象;而后者则能与O型、A型和亚洲I型的FMDV RNA发生杂交反应。对照试验显示:此两种探针与SVDV ssRNA、BTV dsRNA、EHDV dsRNA、DHV ssRNA、PRV DNA、乳鼠组织细胞RNA、BHK_(21)克隆13细胞RNA及DNA等均不出现交叉杂交现象,但与IBR DNA有假阳性杂交反应。 相似文献
997.
998.
J. Ambrožič-Dolinšek M. Camloh J. Žel Maja Kovač Maja Ravnikar L. Carraro N. Petrovič 《Scientia Horticulturae》2008
The aim of the work was to infect pyrethrum (Tanacetum cinerariifolium (Trevir.) Schultz-Bip.), an important secondary metabolite pyrethrin producing plant, with MA phytoplasma (16S rRNA group III, subgroup B) to initiate tissue culture of phytoplasma-infected plants, and to examine possible effects of infection on pyrethrin content, morphology, and regenerative capacity in shoot culture. 相似文献
999.
AIM: To establish a real-time PCR technique for detection and quantification of TCR ζ chain expression and to investigate TCR ζ chain expression level in patients with chronic myeloid leukemia (CML). METHODS: Real-time PCR with SYBR GreenⅠ technology was used for detecting TCR ζ chain expression level in peripheral blood mononuclear cells from 30 patients with CML and 30 normal individuals. β2 -microglobulin gene (β2M) was used as an endogenous reference. Relative changes in TCR ζ chain expression level were used by the 2- △△Ct method between patients with CML and normal individuals. RESULTS: The SYBR GreenⅠ real-time technique for quantitative detection of TCR ζ chain expression levels was established successfully. The expression level of TCR ζ chain in 18 patients with CML was reduced. However, the TCR ζ chain expressed increased in 12 patients with CML. CONCLUSION: The TCR ζ chain expression level is divided into down expression (60%) and over expression (40%) groups, and the down expression of TCR ζ chain might related to cellular immunodeficiency in most of CML patients. 相似文献
1000.
Pharmacokinetics,pharmacodynamics and clinical use of trazodone and its active metabolite m‐chlorophenylpiperazine in the horse 下载免费PDF全文
J. L. Davis J. Schirmer E. Medlin 《Journal of veterinary pharmacology and therapeutics》2018,41(3):393-401
Trazodone is a serotonin receptor antagonist and reuptake inhibitor used extensively as an anxiolytic in human and small animal veterinary medicine. The aims of this study were to determine the pharmacokinetics of oral trazodone in experimental horses and to evaluate the effect of oral trazodone in clinical horses. Six experimental horses were administered trazodone at 7.5 or 10 mg/kg. Plasma concentrations of trazodone and its metabolite (m‐CPP) were determined via UPLC‐MS/MS. Noncompartmental pharmacokinetic analysis, sedation and ataxia scores were determined. Trazodone was rapidly absorbed after oral administration with a maximum concentration of 2.5–4.1 μg/ml and half‐life of the terminal phase of approximately 7 hr. The metabolite was present at low levels in all horses, representing only 2.5% of the total area under the curve. In experimental horses, concentration‐dependent sedation and ataxia were noted, lasting up to 12 hr. For clinical cases, medical records of horses treated with trazodone for various abnormal behaviours were reviewed and data were summarized. Trazodone was successful in modifying behavioural problems to some degree in 17 of 18 clinical cases. Tolerance and subsequent lack of drug effect occurred in two of 18 clinical cases following 14 or 21 days of use. In both populations of horses, adverse effects attributed to trazodone include oversedation, muscle fasciculations and transient arrhythmias. 相似文献