Activation of renal tubular epithelial cells by monocytes/macrophages and the relative mechanisms

AIM: To observe the direct effects of peripheral blood monocytes/macrophages (MO/MAC) on renal tubular epithelial cells (RTEC),and further probe into the possible mechanisms. METHODS: Conditioned medium(M-CM) of human peripheral blood MO/MAC was collected and added to HK-2,a human renal proximal tubular cell line.After incubation with M-CM for 24 hours,HK-2 cells were detected for DNA synthesis by [³H]-TdR incorporation,osteopontin (OPN) and α-smooth muscle actin (α-SMA) expression by Western blot,and fibronectin(FN) secretion by ELISA.Furthermore,anti-TGFβ₁ neutralizing antibody and interlukin-10(IL-10) were used separately to antagonize the effects of M-CM on HK-2 cells. RESULTS: ①DNA synthesis,α-SMA expression and FN secretion were all increased in HK-2 cells when incubated with M-CM.②When adding with anti-TGFβ₁ neutralizing antibody (5 mg/L) in the M-CM,the degree of upregulation of α-SMA and FN in HK-2 cells was much lower than that stimulated by M-CM alone.③M-CM added with IL-10 (20 μg/L) had a weaker ability to induce the increasing in α-SMA expression and FN excretion in HK-2 cells, compared with M-CM itself alone.M-CM from MO/MAC preincubated with IL-10 caused a lower upregulation of α-SMA expression in HK-2 cells than M-CM from non-preincubated MO/MAC. CONCLUSION: MO/MAC can directly induce proliferation,transdifferentiation and extracellular matrix secretion in RTEC.TGFβ₁ and proinflammatory cytokines secreted by MO/MAC might be involved in the aboveeffects.     

Effects of platelet-derived growth factor on DNA and collagen protein synthesis in human vascular fibroblasts

AIM: To investigate the effects of platelet-derived growth factor on DNA and collagen protein synthesis in human vascular fibroblasts. METHODS: In the present experiment, the human vascular fibroblasts were cultured and effects of platelet-derived growth factor-BB on DNA and collagen protein synthesis in human vascular fibroblasts were observed by using [³H]-TdR incorporation and [³H]-proline incorporation in vitro. RESULTS: Platelet-derived growth factor-BB significantly promoted NDA synthesis and collagen protein synthesis of quiescent human vascular fibroblasts, with a maximal response at a concentration of 30μg·L^-1at 24 h and 36 h, respectively. CONCLUSION: Platelet-derived growth factor-BB promotes DNA and collagen protein synthesis in cultured human vascular fibroblasts.     

Effects of carvedilol,cilazapril and their combination on left ventricular remodeling after acute myocardial infarction in rats

AIM:To compare the effects of carvedilol, cilazapril and their combination on left ventricular remodeling(LVRM) after acute myocardial infarction(AMI) in rats. METHODS: Twenty-four hours after AMI operation, 100 surviving rats were randomly assigned to: ①AMI control(n= 25), ②AMI+carvedilol(1 mg·kg^-1 ·d^-1, n= 25)(C1), ③AMI+cilazapril(1 mg·kg^-1 ·d^-1, n= 25)(Z1), and ④ AMI+combination(n= 25) groups. Sham-operated group(n= 17) were selected randomly. After 4 weeks of therapy with the drugs gastric gavage, hemodynamic and pathological studies were performed. RESULTS: There were no significant differences in MI size among the four AMI groups(all P> 0.05) Left ventricular(LV) end diastolic pressure(LVEDP), volume(LVV), weight(LVW) and septal thickness(STh) were all higher and left ventricular pressure maximal rate of rise and fall(±d p /d t) were lower(all P< 0.01) in AMI group than sham-operated group. The LVEDP, LVV, LVW and STh were all lower and ±dp /dt were higher in Z1, C1, and combination groups than those in AMI group(P< 0.05, P< 0.01), with LVEDP and STh were more lower in the combination group than in the two monotherapy group(P< 0.05, P< 0.01), but there were no significant differences in other variables among the three therapy groups. CONCLUSION: Carvedilol, cilazapril and their combination all can prevent from LVRM after AMI in rats, improve hemodynamics and LV function, with the combination superior.     

Protein expression of cyclin D2 and p16 in proliferation and differentiation of cultured cardiac myocytes

AIM:To investigate the protein expression of cyclin D₂ and p16 in proliferation and differentiation of cultured cardiac myocytes.METHODS:One-day-old Sparague-Dawley rats were used. Cardiac myocytes(CM) were collected by a trypsin-dispersal method and cultured. Cell growth line and fluorescence activated cell sorting (FACS) were used to investigate the proliferation of CM. Ultra-thin sections were made to observe the ultrastructure of CM under transmission electron microscope. The expression of cyclin D₂ and p16 in CM were measured using immunocytochemistry and image analysis.RESULTS:①Results of cell growth line and FACS analysis showed that cultured CM could proliferate in the first 3 cultured days, but the ability decreased quickly, concomitant with differentiation. CM was obseved quiescent in cell cycle three days later. The ultrastructure of CM showed the large amount of myofilaments and mitochondrion. ②The protein expression of cyclin D₂ in 3,4,5 day CM group was 0.89 times(P＜0.05),0.80 times (P＜0.05) and 0.56 times (P＜0.01) of that in 1 day group, respectively. The expression of p16 in CM was increased during the culture process, 2,3,4,5 day group were 1.63 times, 1.72 times, 1.99 times and 2.84 times (P＜0.01) of that in 1 day group, respectively.CONCLUSION:Cultured neonatal rat cardiac myocytes could proliferate during the first 3 days after incubation, but the ability of proliferation decreased, from the fourth day, concomitant with differentiation. Cyclin D₂ and p16 play the key roles in CM postnatal development. Downregulation of cyclin D₂ and upregulation of p16 may induce CM differentiation.     

两系稻制种穗期病害发生较重的原因及防治措施

调查分析稻粒黑粉病、穗颈稻瘟等两系杂交稻制种穗期主要病害的发生原因,提出了清除菌源、轮换制种、健身栽培、对口药剂防治等防治措施。     

昆虫神经肽类激素的研究及应用前景

由昆虫脑神经内分泌细胞分泌的神经肽类激素 ,咽侧体活化激素 (allatotropin ,AT)和咽侧体抑制激素 (al latostatin ,AS) ,分别刺激或抑制咽侧体的保幼激素的生物合成 ,从而控制昆虫的生长、发育和变态。利用昆虫神经内分泌的失调 ,使其体内激素水平失调 ,来达到控制害虫的目的。     

温湿度调控对番茄灰霉病菌产生的细胞壁降解酶的影响

 番茄灰霉病菌在致病过程中能够产生4种细胞壁降解酶,以PMG酶活性最高,其次是β-葡萄糖苷酶和PG酶,Cx最少。灰霉病菌在不同温度下侵染番茄叶片时产生的致病酶活性不同,4种酶在20℃时表现了最高的活性,15℃次之,当温度达到25℃时,各种酶的活性都急剧下降,随着温度的再升高,酶活更低。随着湿度的增高,病菌产生的细胞壁降解酶的活性也增加,当相对湿度达到90%以上时,4种酶的活性也达到最高。温湿度对番茄灰霉病菌产生细胞壁降解酶的影响趋势,与其对发病的影响趋势是一致的。     

阿魏蘑与杏鲍菇高产优质栽培模式研究

试验证明，阿魏蘑和杏鲍菇最佳栽培模式为菌棒半脱袋竖向畦栽半覆土栽培模式；最适环境条件为菇房温度13～20℃，空气相对湿度85％～95％；最佳栽培设施为半地下冬暖式塑料大棚。     

施肥对黔中地区混播草地牧草生长性能的影响

本文研究了氮磷钾不同配比施肥量对黑麦草和紫花苜蓿混播草地牧草生长的影响,结果表明:氮肥促进禾本科牧草叶的生长(P<0.05),增施钾肥对禾草的生长有利;磷能促进豆科牧草根的生长(P<0.05)且豆科牧草株高随着施磷量的增加各处理间差异显著(P<0.05),高氮抑制豆科牧草的生长;最高产量的施肥方式:N:P_2O_5:K_2O为20:30:20,比对照处理的草地产量增加63.92％。     

苹果矮化砧木‘辽砧2号’选育

从1135系的助列涅特与M9杂交实生苗中选出优良苹果矮化砧木—辽砧2号(原代号80-1-6),经过22年田间观查和区试鉴定,其矮化性、早果性、丰产性、生根性与M26相近,适应性强于M26,以其为中间砧的富士树栽后6年进入盛果期,平均株产为23.5kg,同龄M26为17.2kg;8年生树冠积为4.07m3,同龄M26为4.58m3,树体存活率较M26高55%,平均每666.7m2产量1000kg以上;与基砧山定子和生产上主栽的富士系、元帅系、国光系等品种亲和性良好,以自根砧和中间砧方式利用均可。