Effect of peroxisome proliferator-activated receptor γ agonist rosiglitazone on intestinal injury in rats undergoing orthotopic autologous liver transplantation by inhibiting inflammatory response

AIM: To investigate the effect of rosiglitazone, a peroxisome proliferators-activated receptor γ(PPARγ) agonist, on the expression of PPARγ, the activation of NF-κB and intestine injury in the rats undergoing orthotopic autologous liver transplantation(OALT).METHODS: Sprague-Dawley male rats were randomly divided into 4 groups:control group, sham group, OALT group and rosiglitazone(0.3 mg/kg, iv) pretreatment(ROS+OALT) group. The OALT model was established, and the intestinal tissues were collected 8 h after the liver reperfusion. The intestinal tissue sections were stained to visualize the damage. The expression of PPARγ and NF-κB in the tissues, the concentrations of diamine oxidase(DAO) and fatty acid-binding protein 2(FABP2) in the serum and the concentration of TNF-α and IL-6 in the tissues were measured.RESULTS: Compared with sham group, the intestinal mucosa of the rats showed obvious pathological injury after liver reperfusion in OALT group and ROS group, the Chiu,s scores of intestinal mucosa was significantly higher, and the serum concentrations of DAO and FABP2 increased(P<0.05). After rosiglitazone pretreatment, the injury of intestinal mucosa of the rats was alleviated, the Chiu,s scores was lower and the serum concentrations of DAO and FABP2 decreased(P<0.05), the PPARγ expression was obviously up-regulated in the intestinal tissues, the nuclear translocation of NF-κB was reduced and the concentrations of IL-6 and TNF-α were decreased.CONCLUSION: During perioperative period of OALT in rats, the inflammatory responses are obvious. Furthermore, obvious intestinal injury occurs. PPARγ agonist rosiglitazone obviously up-regulates PPARγ expression and inhibits the inflammation in the intestines, thus protecting against intestinal injury in rats undergoing OALT.     

miR-21 inhibits apoptosis of Schwann cells following peripheral nerve injury

AIM: To explore the relationship and molecular mechanism between microRNA-21(miR-21) and Schwann cells (SC) following peripheral nerve injury. METHODS: The mRNA expression of miR-21 and phosphatase and tensin homologue deleted on chromosome ten (PTEN) in animal model were detected by real-time PCR. The over-expression of miR-21 and inhibition of miR-21 expression in the Schwann cells according to transfection of lentiviral vectors were performed, the nonspecific miRNA was used as a negative control (NC). The cell apoptosis was measured by flow cytometry. The mRNA expression of miR-21 and PTEN in the cells was detected by real-time PCR. The protein expression of PTEN and cleaved caspase-3 was determined by Western blot. RESULTS: The level of miR-21 was significantly higher and the mRNA level of PTEN was significantly lower in the model of nerve injury than those in control group. miR-21 over-expression decreased the number of apoptotic Schwann cells compared with NC-SC. The mRNA expression of PTEN was down-regulated by over-expression of miR-21. The protein expression of PTEN and cleaved caspase-3 was down-regulated by over-expression of miR-21(P<0.05). CONCLUSION: miR-21 may play an important role in the peripheral nerve injury through inhibiting apoptosis of Schwann cells by down-regulating the expression of PTEN.     

平欧杂种榛主栽品种需冷量、需热量研究

[目的]揭示平欧杂种榛主栽品种的需冷量和需热量,更好地指导生产做好区域化栽培。[方法]本研究以16个平欧杂种榛主栽品种的1年生枝条为试材,以野生平榛1年生枝条为对照,通过水培观察的方法,首次对平欧杂种榛的雌、雄花序和叶芽进行需冷量和需热量研究。[结果]表明:平欧杂种榛不同器官的需冷量由低到高依次为雄花序336 1 176 h、雌花序504 1 344 h、叶芽672 1 512 h;需热量由低到高依次为雄花序687.0 998.5GDH℃、雌花序998.5 3 496.1 GDH℃、叶芽2 546.5 4 180.3 GDH℃;不同品种、器官在刚满足最低蓄冷要求时需热量最高,随着蓄冷时间的延长,需热量逐渐减少。[结论]首次报道了平欧杂种榛主栽品种雄、雌花序和叶芽的需冷量和需热量数据,其中,达维、平欧48号等品种花器官需冷量较低,辽榛2号、平欧545号等品种花器官需冷量较高;玉坠、平欧69号等品种花器官需热量较低,辽榛1号、辽榛4号等品种花器官需热量较高,上述研究丰富了榛属植物开花和休眠解除方面的数据,可为平欧杂种榛的引种和栽培提供参考。     

杉木的受害允许水平及粗鞘双条杉天牛防治策略研究

本文在９年生人工纯林中，采用固定标准地、固定标准株连续３年对树高、胸径实测的方法，计算并比较阌 害与末受害木材积及单位面积材积的 失。     

凤县花椒春季霜冻的气候分析

本文对凤县花椒霜冻的气候因素进行了分析。结果认为,凤县花椒霜冻在时间分布上主要集中出现于春4月上、中旬。霜冻在空间分布上具有随海拔升高而加重、随地域不同而多变的特点。凤县霜冻的发生以"平流+辐射霜冻"为主,以"平流霜冻"或"平流+辐射霜冻"对花椒造成的危害最大。花椒受害的严重程度还与低温程度、降温强度、降温时的空气湿度、低温持续时间、霜冻类型、霜冻出现时间及椒园管理状况密切相关。     

低温冻害对蚕豆幼苗生理生化特性的影响及RAP-PCR指纹分析

0℃冻害分别处理蚕豆幼苗0、3、6、12 h,测定了蚕豆幼苗叶片的蛋白质、脯氨酸、还原性谷胱甘肽和丙二醛等生理指标,进行了蚕豆低温胁迫下的RAP-PCR指纹分析和抵抗低温冻害的特异基因序列片段的克隆.结果表明:随着低温胁迫的加强,蚕豆幼苗叶片内蛋白质含量呈现先升后降的趋势,脯氨酸相对百分含量逐渐增加,还原性谷胱甘肽含量...     

温度调控对北方盆栽蓝莓开花的影响

以北方盆栽蓝莓美登和北蓝为研究对象,通过人为温度控制,促使盆栽蓝莓提前开花。研究表明,盆栽美登(Blomidon)在需冷量达到1200h,盆栽北蓝(Northern blue)在需冷量达到1000h情况下,可以通过温度调控,打破盆栽蓝莓休眠期,达到提前开花的目的。     

抗寒植胶仍是云南垦区不容忽视的问题

根据赵振国研究员所言“30年冷周期”即将来临的预测,针对河口垦区不够重视橡胶树寒害问题的倾向,回顾了河口植胶半个世纪以来的橡胶树寒害及损失情况,提醒人们:寒害曾经发生,并且还会发生,云南垦区抗寒植胶不容忽视。     

冷害桃果实品质劣变及其控制措施

概述了在贮藏期间,桃果实受到冷害后其色泽、质地和风味等品质劣变机理及控制冷害的措施。桃果实的低温褐变主要是酶促褐变,但对不同的品种来说,决定褐变的主导因子则不尽相同。在产生絮败的果实中,果胶物质发生了代谢异常,不溶性果胶明显增加,果胶质代谢异常与PE和PG的活性变化密切相关。桃果实的糖分主要是蔗糖,当冷害出现时桃果实中蔗糖含量迅速下降,可滴定酸含量在贮藏期间也显著下降。目前已从桃果实中分离到近百种芳香成分,冷害桃果实的重要表现之一是原有桃香气变淡或丧失,甚至产生异味。品种与采收成熟度、采前或采后的化学处理、低温锻炼、热调处理和气调均能够不同程度地减轻桃果实的冷害。     

低温锻炼对冷胁迫下油茶幼苗光合速率与抗氧化酶活性的影响

以油茶品种"杂优闽1"为试验材料,以未经低温锻炼的油茶幼苗为对照,研究了油茶幼苗在(10±0.5)℃低温锻炼、(2±0.5)℃冷胁迫和常温恢复期间的光合速率和抗氧化酶活性的变化。结果表明:低温锻炼3 d可明显提高油茶幼苗的抗寒性;冷胁迫3 d,经低温锻炼后的油茶幼苗叶片净光合速率和相对含水量明显高于对照;且其在常温下的恢复也较对照迅速。在低温锻炼和冷胁迫期间,油茶幼苗叶片脯氨酸和可溶性糖含量明显增加,且丙二醛(MDA)含量明显低于对照;经低温锻炼的油茶幼苗叶片超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和抗坏血酸过氧化物酶(APX)活性则均明显高于未经低温锻炼的油茶幼苗,说明渗透调节物质含量增加和保护酶活性增强在低温锻炼诱导油茶幼苗的抗寒性上发挥着重要的作用。