The mitogenic activity decline of a haFGF mutant and its mechanism

AIM: To observe the effects of the human acidic fibroblast growth factor mutant (mhaFGF)， lacking 27 amino acids at N-terminal， on the proliferation and signal transduction of the hepatocarcinoma cells. METHODS: The hepatocarcinoma cells were treated with human acidic fibroblast growth factor (haFGF) and mhaFGF, respectively. The expression levels of the signal proteins, Grb2 and Erk1/2, in the hepatocarcinoma cells were detected by semi-quantitative Western-blotting after treated for 15 min. The mitogenic activity of both haFGF and mhaFGF was detected by MTT method and the cell cycle was analysed by flow cytometer (FCM) after treated for 48 h. RESULTS: The mitogenic activity and the ratio of G1 and S phase cells in mhaFGF-treated cells were markedly lower than that of the haFGF, and close to that of the control group. The expression level of both Grb2 and Erk1/2 in the mhaFGF-treated cells were lower than those in the haFGF- treated cells. CONCLUSION: The decrease in the mitogenic activity of mhaFGF is probably associated to its down-regulating the expression of the signal molecular, MAPK-ERK1/2 and Grb2.     

动态载荷下基于声发射技术的杨木破坏过程检测

利用声发射检测和力学试验相结合的方法,研究山杨木材在动态载荷下的声发射演变过程;结合木材粘弹性特点,通过声发射参数分析研究在不同受力阶段木材的声发射特点.结果表明:1)声发射信号幅值不连续,是跃迁的;材料断裂前声发射信号的幅值和能量比断裂后小,在断裂点对应声发射信号幅值和能量的局部极大值.2)随时间和载荷的变化,声发射累计撞击数和累计能量增加快慢可以体现杨木在受力条件下的完全弹性、弹性为主的弹塑性共存、塑性为主的弹塑性共存3种状态.3)声发射率和幅值参数可以预测材料纤维开始断裂进入危险期的第一"临界点"和材料大量纤维断裂进入严重危险期的第二"临界点",如果继续加载材料将会破坏断裂.     

Prognostic prediction of PTEN and Her-2 expression in breast cancer

AIM:To study the prognositic value of PTEN and Her-2 expression in primary breast cancer. METHODS:81 breast cancer specimens with 15 years follow-up were obtained from 1989 to 2004. Immunohistochemical methods were used to detect the expression of PTEN and Her-2 in 81 paraffin-embedded specimens. The correlation between expression of PTEN and clinipathological factors was discussed with the Chi-square test. The survival rate analysis results were calculated with Kaplan-meier method.Long-rank test and Cox model by SPSS 10.0 software. 〖JP+1〗RESULTS:(1) PTEN expression significantly affects 5-year and 10-year survival rate of breast cancer (P<0.01 and P<0.05), and significantly negative correlation with the Her-2 expression was observed. (2) The patients with negative PTEN combined with positive Her-2 expression had worse prognosis. (3) Tumor sizes, postoperative therapy and PTEN expression had significant relation with the 5-year survival rate (P<0.05), and ER, Her2 and PTEN expression had significant relation with the 10-year survival rate (P<0.05). CONCLUSION:PTEN and Her-2 expression significantly affects 5-year and 10-year survival rate in patients with breast cancer, and may be biomarkers and important prognostic factors in breast cancer.     

Sequencing, Polymorphism and Expression Profile Analysis of Porcine Hexokinase Ⅱ (HK2) Gene

Hexokinase Ⅱ has been demonstrated to play the role of a key enzyme member in the glycolysis reaction. It catalyzes the conversion of glucose to glucose-6-phosphate, thus committing glucose to the glycolytic pathway. In this paper, the partial exons and introns 10, 11, 13 and 14 of the porcine HK2 gene were cloned and sequenced by comparative genomics.Comparative sequencing of three pig breeds revealed ten putative single-nucleotide polymorphisms (SNPs), one of which in intron 10 with differing bases (G981A) is within the restriction site for enzyme Msp Ⅰ. Distribution of Msp Ⅰ -RFLP genotype and allele frequencies among different pig breeds were studied. By association analysis between Msp Ⅰ PCR-RFLP polymorphism (AA, AB, BB genotypes of HK2 gene intron 10) and some meat quality and carcass traits in F2 group,which was constructed by our laboratory, a significant difference of pig average backfat at rump was found between AB and BB genotypes (P ＜ 0 05) in F2 group. In addition, the pattern of expression of HK2 in a variety of tissues in pig was also determined using semi-quantitative RT-PCR. The expression of HK2 mRNA was detected only in pig skeletal muscle.     

7种药剂对苹果红蜘蛛的防治作用研究

通过试验,明确了7种药剂对苹果红蜘蛛的防治作用,为安全、合理使用和大面积推广提供一定理论依据。     

雏鸡感染柔嫩艾美耳球虫后脂质过氧化物的变化

为了探讨柔嫩艾美耳球虫 (E.tenella)对感染雏鸡的损伤机制 ,本试验给 10日龄海兰白公雏鸡口服柔嫩艾美耳球虫孢子化卵囊 8× 10 4个 /只 ,在感染后 2、4、6、7、9、12、16和 2 1d分别各取 5只雏鸡剖检 ,取盲肠并采血 ,观察盲肠病理组织学变化 ,测定盲肠组织及血清中的丙二醛 (MDA )、超氧化物歧化酶 (SOD)、谷胱甘肽过氧化物酶 (GSH- Px)的水平。结果表明 ,雏鸡在感染 E.tenella后 2～ 4d,盲肠开始出现损伤 ,同时 SOD和 GSH- Px活性也开始下降 ;感染后 4～ 7d,盲肠粘膜上皮和肠腺上皮细胞大量变性、坏死崩解 ,发生严重损伤时 ,盲肠及血清中 MDA含量显著增加 ,并持续到 9d,同时 SOD和 GSH- Px活性也显著下降 ;感染 9d后 ,损伤的盲肠组织及 MDA、SOD和 GSH- Px水平逐渐恢复 ,至 2 1d基本达到正常     

走马芹根部提取液对几种常见森林害虫的防治试验

利用33％的走马芹根部提取液对落叶松毛虫、分月扇舟蛾进行防治试验，防治效果较好，分别达到93．1％和85．12％，而对青杨虎天牛的作用较差，防治效果只有26．67％。     

鸡球虫苗的研究进展

由于抗药性和研制新药成本增加，周期延长，药物使用中存在的一些问题，促进了免疫学防治的发展，利用鸡球虫苗来控制鸡球虫病成为一种有效途径，通过对鸡球虫苗的种类，作用特点，研究概况等方面的论述，进一步提出该虫苗的应用前景及展望，为更好地防治鸡球虫提供科学依据。     

Effects of chlorine gas exposure on lung haemodynamic and respiratory function in intact and isolated perfused rabbit lungs

AIM:To investigate the effect of high concentration of chlorine gas(Cl₂) exposure on lung haemodynamic and respiratory function in intact and isolated perfused rabbit lungs (IPLs). METHODS:8 intact and 10 IPLs were exposed to Cl₂ at high concentration(50×10^-4)for 20 min, as measured group, 8 additional intact and 9 IPLs, which were similarly treated but not exposed to Cl₂, served as controls. The changes of lung weigh of IPL(△W)、pressure of pulmonary artery(Pa)and venous pressure(Pv)、airway pressure and tidal volume(TV) were continuously measured and recorded simultaneously. RESULTS: In IPL group: While the perfusing blood flow was kept constant (133.3 mL/min), and Pv did not change, following the exposure, the Pa increased slightly, then the lung weight were increased significantly and the TV decreased . Hematocrit of perfusate of EIPL and parameters of lung water increased also. In intact group: Pa increased slightly, respiratory rate accelerated immediately, and TV decreased. CONCLUSION:Although mean Pa increased continuously and slightly in both intact and IPL group following the exposure to high concentration of Cl₂, the primary cause of edema was most likely to alter pulmonary capillary permeability. The respiratory rate accelerated and TV decreased due to exposure to Cl₂ enhanced hypoxia of intact rabbits.