中科院北京植物园壳斗科植物鉴定

利用DNA条形码技术对中科院北京植物园壳斗科专类园的23份植物材料进行鉴定,从Genebank中获得相关数据,选择matK、rbcL、trnH-psbA序列引物对样本材料进行PCR扩增和测序,通过比较各序列的扩增效率、有效片段获得率,用PAUP4.0 b10建物种关系树评价不同序列的鉴定能力。本研究认为,matK序列物种鉴别能力最高,种间变异差异最大的为trnH-psbA序列,rbcL相对保守。     

Effects of dietary carbohydrate sources on plasma glucose, insulin and IGF-I levels in multiparous sows

Effects of different carbohydrate sources on plasma glucose, insulin and insulin-like growth factor-I (IGF-I) levels were compared to subsequently be able to study effects of insulin-stimulating diets on follicle development in sows. The following feed components were tested in 12 sows during six consecutive test periods of 9.5 days: dextrose (DEX), sucrose (SUC), lactose (LAC), dextrose plus lactose (DL), sucrose plus lactose (SL), dextrose plus sugarbeet pulp (DSBP) and control (CON). On day 2, 5 and 9 of each test period, plasma glucose (only at day 9), insulin and IGF-I profiles were determined. Despite similar glucose profiles for all diets, the postprandial insulin response was higher for DL and SL compared with CON and LAC; the other diets were intermediate. Plasma IGF-I levels were higher in CON, LAC and SL compared with DSBP, but differences were only marginal. It was concluded that dextrose and sucrose have the potential to stimulate fast and high insulin peaks, especially when combined with additional lactose. Despite the high dextrose in the DSBP diet, the insulin response was flattened, probably due to the viscosity of sugarbeet pulp. The results show that modulation of plasma insulin levels by dietary carbohydrates seems possible in anabolic sows, but IGF-I levels are less easily modified.     

Artesunate negatively controls expression of cyclin D1 and activity of AP-1 by inhibiting the activation of ERK1/2 protein in HSC-T6 cells

AIM: To investigate the effects of artesunate(Art) on the expression of ERK1/2, AP-1 and cyclin D1 in rat hepatic stellate cells (HSCs), and to elucidate the molecular mechanism of Art against hepatic fibrosis. METHODS: HSC-T6 cells were treated with platelet-derived growth factor BB(PDGF-BB) to induce cell proliferation. The cells were divided into control group, PDGF-BB group, PDGF-BB+Art groups (with 6.25 mg稬^-1, 25 mg稬^-1or 50 mg稬^-1 of Art) and PDGF-BB+PD98059 group. The level of collagen type I in the supernatant was detected by enzyme-linked immunosorbent assay (ELISA). The mRNA expression levels of ERK1/2 and cyclin D1 were measured by RT-PCR. The protein levels of p-ERK1/2 and cyclin D1 in HSC-T6 cells were detected by Western blotting. The activity of AP-1 was analyzed by electrophoretic mobility shift assay. RESULTS: The concentration of collagen type I was significantly higher in PDGF-BB group than that in control group (P<0.05), and decreased in PDGF-BB+Art group and PDGF-BB+PD98059 group in comparison with that in PDGF-BB group (P<0.05, P<0.01). The protein level of ERK1/2 in PDGF-BB+Art group (50 mg稬^-1) was lower than that in PDGF-BB group (P<0.05), and was even lower in PDGF-BB+PD98059 group (P<0.01). The mRNA expression of cyclin D1 in PDGF-BB+Art groups (25 mg稬^-1and 50 mg稬^-1) and PDGF-BB+PD98059 group were significantly lower than that in PDGF-BB group (P<0.05). The protein levels of p-ERK1/2 and cyclinD1 were the highest in PDGF-BB group, and significantly lower in PDGF-BB+Art groups (6.25 mg稬^-1, 25 mg稬^-1 and 50 mg稬^-1) and PDGF-BB+PD98059 group (P<0.05, P<0.01). The AP-1 binding activity in HSC-T6 cells was down-regulated by Art. CONCLUSION: Artesunate inhibits the proliferation of HSC-T6 cells in vitro by inhibiting the activation of ERK1/2, thus down-regulating the activity of AP-1 and expression of cyclin D1.     

Echinacoside promotes bone regeneration by increasing OPG/RANKL ratio in MC3T3-E1 cells

Echinacoside (ECH), isolated from Cistanche tubulosa (Schrenk) R. Wight stems, was subjected to in vitro experiments to investigate its bioactivities on proliferation, differentiation and mineralization of the osteoblastic cell line MC3T3-E1. MTT assay, the alkaline phosphatase (ALP) activity and calcium deposition were determined, and the secretion of collagen I (COL I), osteocalcin (OCN), osteoprotegerin (OPG) and receptor activator of nuclear factor-κB ligand (RANKL) were also assayed by enzyme-linked immunosorbent assay (ELISA). The results showed that ECH caused a significant increase in cell proliferation, ALP activity, COL I contents, OCN levels and an enhancement of mineralization in osteoblasts at the concentration range from 0.01 to 10 nmol·L^− 1 (p < 0.05), suggesting that ECH has a stimulatory effect on osteoblastic bone formation or has potential activity against osteoporosis. In addition, the ratio of OPG/RANKL also could be enhanced by ECH. These findings provide the potent evidence that ECH can promote bone regeneration in cultured osteoblastic MC3T3-E1 cells, which might be done by elevating the OPG/RANKL ratio, and potential evidence for echinacoside to be a promising drug or a lead compound in the development of disease-modifying drug to prevent osteoporosis.     

番茄褐色皱果病毒SYBR Green Ⅰ实时荧光RT-PCR检测方法的建立和应用

根据番茄褐色皱果病毒(tomato brown rugose fruit virus,ToBRFV)外壳蛋白(coat protein,CP)的保守基因序列设计l对特异性引物,建立了基于SYBR Green Ⅰ的ToBRFV实时荧光RT-PCR检测方法,并对其进行了特异性、灵敏度检测,对自然感染ToBRFV的番茄、辣椒...     

茶尺蠖核型多角体病毒(EoNPV)实时荧光定量PCR检测方法的优化及应用

选用茶尺蠖核型多角体病毒(EoNPV)基因组中序列特异性很高的p16基因为目标基因,通过设计引物、PCR扩增、目的片段与载体连接转化获得含p16基因的重组质粒进行测序,进而以经测序鉴定的p16基因的PCR纯化产物作为实时荧光定量PCR标准品模板,稀释后建立SYBR Green I荧光定量标准曲线,统计分析显示标准品浓度的对数值与Ct值之间存在良好的线性关系(R2=0.9981)。该方法的检测灵敏度为102,扩增产物形成单一的特异性熔解峰,组内组间变异系数均小于3%。同时分别对含有其他茶树害虫病毒和不同浓度的茶尺蠖病毒产品的样品进行检测,能明确样品中是否含有EoNPV及含量。根据已建立的方法对感染病毒后不同时间段的茶尺蠖幼虫进行检测,每克幼虫样本内p16基因拷贝数的增殖倍数对数值与感染时间呈正相关(R2=0.9935),可以获得茶尺蠖幼虫感染病毒后不同时间的增殖动态。上述结果表明,该方法能定性定量鉴定茶尺蠖核型多角体病毒,可用于茶尺蠖核型多角体病毒类生物农药的检测和感染过程检测。     

Time-dependent changes of calbindin D-28K and parvalbumin immunoreactivity in the hippocampus of rats with streptozotocin-induced type 1 diabetes

The hippocampus is affected by various stimuli that include hyperglycemia, depression, and ischemia. Calcium-binding proteins (CaBPs) have protective roles in the response to such stimuli. However, little is known about the expression of CaBPs under diabetic conditions. This study was conducted to examine alterations in the physiological parameters with type 1 diabetes induced with streptozotocin (STZ) as well as time-dependent changes in the expression of two CaBPs changes of were being evaluated. Rats treated with STZ (70 mg/kg) had high blood glucose levels (>21.4 mmol/L) along with increased food intake and water consumption volumes compared to the sham controls. In contrast, body weight of the animals treated with STZ was significantly reduced compared to the sham group. CB-specific immunoreactivity was generally increased in the hippocampal CA1 region and granule cell layer of the dentate gyrus (DG) 2 weeks after STZ treatment, but decreased thereafter in these regions. In contrast, the number of PV-immunoreactive neurons and fibers was unchanged in the hippocampus and DG 2 weeks after STZ treatment. However, this number subsequently decreased over time. These results suggest that CB and PV expression is lowest 3 weeks after STZ administration, and these deficits lead to disturbances in calcium homeostasis.     

Effects of photoperiod on secretory patterns of growth hormone in adult male goats

The aim of the present study was to clarify the effect of photoperiod on secretory patterns of growth hormone (GH) in male goats. Adult male goats were kept at 20°C with an 8‐h or 16‐h light photoperiod, and secretory patterns of GH secretion were compared. In addition, plasma profiles of prolactin (PRL), insulin‐like growth factor‐I (IGF‐I) and testosterone (T) were also examined to characterize GH secretion. GH was secreted in a pulsatile manner. There was no significant difference in pulse frequency between the 8‐h and 16‐h photoperiods. However, GH pulse amplitude tended to be greater in the group with the 16‐h photoperiod (P = 0.1), and mean GH concentrations were significantly greater in the 16‐h photoperiod (P < 0.05). The GH‐releasing response to GH releasing hormone was greater in the 16‐h than 8‐h photoperiod (P < 0.05). Plasma PRL and IGF‐I levels were higher in the 16‐h than 8‐h photoperiod (P < 0.05). In contrast, plasma T levels were lower in the 16‐h photoperiod (P < 0.05). These results show that a long light photoperiod enhances the secretion of GH as well as PRL and IGF‐I, but reduces plasma T concentrations in male goats.     

鸽副黏病毒Ⅰ型(川沙株)的分离与鉴定

利用SPF鸡胚培养法从上海川沙某具有典型新城疫症状和病理变化的高死亡率发病鸽场的死亡鸽体内分离到一株病毒.对该病毒E5代尿囊液进行病原学鉴定、RT-PCR鉴定、理化特性测定、致病指数、病毒血清学试验及鸽体致病性试验,结果显示该病毒具有血凝性,且血凝特性可被新城疫病毒参考阳性血清所抑制,而不能被减蛋综合征病毒、禽流感病毒（H5、H9和H7）阳性血清抑制;该病毒对氯仿、乙醚和酸敏感;致病指数分别为：最小致死量鸡胚平均死亡时间为55.2 h,1日龄雏鸡脑内致病指数为1.8,6周龄雏鸡静脉致病指数为2.39.经鉴定,该分离毒株为鸽副黏病毒Ⅰ型强毒株,将其命名为鸽副黏病毒Ⅰ型（川沙株）.