基于可控性生态减渗目标的河床底质重构技术研究

位于地下水超采区且具有景观要求的河流,需同时具备维持生态水位和渗透补给地下水的功能,研究可调控减渗效果的河床底质重构技术对维持河床垂向连通性具有重要意义。以华北平原常见河床底质和膨润土为主要材料配比得到重构底质,通过变水头渗透试验与模型入渗试验探究了重构底质减渗特性,根据不同河流条件提出不同的配比及结构方案,减渗层厚度和纳基膨润土配比方案1为100 mm和9%,方案2为150 mm和15%,方案3为200 mm和18%;利用GeoStudio SEEP/W软件计算模拟了不同方案的渗流及渗流量减少状况。结果表明,改变膨润土类型和掺量可调节底质的减渗效果,使其渗透系数达到小于1×10^-7cm/s和小于1×10^-6cm/s目标水平;纳基膨润土掺量为15%的重构底质在1 m水头渗透作用下,浸润锋经39 d运移15 cm,56 d内累计入渗量为11.1 cm,减渗效果较好;模拟结果表明,3种减渗方案有不同的减渗效果,典型断面河流水位在0.3～2.0 m时,3种方案河流渗流损失量可降低55.8%～68.8%、91.5%～94.3%和94.8%～96.5%...     

猪GPX5基因、FUT1基因和NCOA1基因的多态性分析

采用PCR-RFLP法对大自猪、杜洛克、长白猪、民猪和野家杂交猪的谷胱甘肽过氧化物酶5(Glutathion-Peroxidase 5,GPX5)基因、岩藻糖转移酶1(Fucosyltransferase1,FUT1)基因和核受体辅激活蛋白1(Nuclear receptor co-aetivator 1,NCOA1)基因进行多态性检测,结果表明:GPX5基因用Hinf I酶切可获得3种基因型,FUT1基因用Hha I酶切可获得3种基因型,NCOA1基因用Rsa I酶切可获得3种基因型.同时对不同基因的基因型频率和基因频率进行计算,并分析相应基因的遗传效应.     

甲基磺酸乙酯对草莓愈伤组织的生理效应

用不同浓度甲基磺酸乙酯对草莓愈伤组织进行诱变处理,测定了愈伤组织中的保护酶和氧化酶活性、总酚含量、MDA含量的变化以及愈伤组织的死亡率。结果表明,随着EMS处理浓度的增加和时间的延长,愈伤组织死亡率呈上升趋势;随着EMS处理浓度的增加,保护酶SOD,CAT和氧化酶PPO,POD活性升高,而后快速下降;随着处理时间的延长,SOD活性逐渐下降,CAT,PPO活性先上升后下降,POD活性则表现为先降后升再降;随着处理浓度的增加和时间的延长,总酚含量变化为先升后降,但上升和下降都比较缓慢,而MDA含量则逐渐上升;处理后的愈伤组织在培养过程中,PPO,POD活性迅速下降并维持在相对稳定的水平,总酚和MDA含量逐渐下降,而总酚含量与PPO,POD活性呈显著正相关。由此认为,在用EMS对草莓愈伤组织进行诱变时,较适宜的剂量为0.1%~0.2%浓度处理1.0~1.5 h,在处理完成后的前12 h培养中,应采取措施以减轻褐变。     

旋毛虫南阳猪体分离株的生物学特性研究

观测了旋毛虫南阳猪体分离株的形态大小,测定了其在小鼠和猪体中的繁殖力指数、雌虫体外产新生幼虫的能力和对低温的耐受性。测得该虫株雄成虫、雌成虫和发育充分的肌幼虫的长宽度分别为(1.415±0.164)mm×(0.048±0.014)mm,(2.627±0.246)mm×(0.056±0.018)mm和(1.112±0.185)mm×(0.038±0.013)mm;其在昆明小白鼠和三元杂交猪体中的繁殖力指数分别为(112.0±59.65)和142.5;平均每条雌虫体外产新生幼虫(56.76±5.13)条;在猪肉中的感染性肌幼虫置-32℃36 h或-22℃60 h即全部死亡。结果表明,该旋毛虫南阳猪体分离株的上述生物学特性与猪旋毛虫(T.spiralis)的特性相似。     

玉米叶片保绿度F1杂种优势与环境互作效应分析

采用加性-显性及与环境互作的遗传模型,利用玉米6个亲本,按完全双列杂交设计组配的15个杂交组合在4种环境条件下的试验资料,分析玉米叶片保绿度F1杂种优势与环境互作效应。结果表明:玉米叶片保绿度F1杂种优势存在着极显著的基因型与环境互作效应。不同杂交组合在同一环境下的F1杂种优势表现不尽相同,同一杂交组合在不同环境条件下表现也不尽相同。玉米自交系沈137是选育保绿性玉米杂交种较好的亲本材料。     

Effect of poly(ADP-ribose) polymerase on the response of guinea pig tracheas induced by peroxynitrite in vitro

AIM and METHODS: to elucidater the effect of poly(ADP-ribose) polymerase(PARP) on tracheal hyperreactivity of guinea - pig induced by peroxynitrite, the responses of guinea pig tracheas to histamine af- ter incubation with peroxynitrite in the absence and presence of 3 - aminobenzamide(3 - AB), a highly selective inhibitor for PARP, were observed in vitro. RESULTS: The exposure of tracheal strips to peroxynitrite led to epithelial damage and hyperreacitivity to histamine, both of which were reversed by 3 - AB(lmmol/L or 5mmol/L), whereas incubation of tracheal strips with 3 - AB(5mmol/L) had no effect on the reponses. CONCLUSION: PARP is involved in the epithelial damage and hyperreactivity of guinea - pig tracheas induced by peroxynitrite. The results suggested that inhibition of excessive activation of PARP may represent a novel strategy for the prevention and therapy of airway hyperreactivity in asthma.     

Effects of EBV infection on growth and apoptosis of nasopharyngeal carcinoma cell line

AIM: To explore the effect of EBV infection on growth and apoptosis of nasopharyngeal carcinoma(NPC) cell line.METHODS: NPC cell line CNE1 was directly infected by Epstein Barr virus (EBV). The expression of EBV-latent membrane protein 1 (EBV-LMP1) and bcl-2 were detected by immunohistochemistry method (LSAB). The growth of NPC cells was identified by MTT method. Apoptotic carcinoma cells were detected by flow cytometry analysis and the terminal deoxynucletidyl transferase-medicated dUTP-biotin nick end labeling (TUNEL) methods. RESULTS: EBV-LMP1 was positive in CNE1 infected by EBV(E-CNE1). Compared with CEN1, the growth of E-CNE1 apparently increased (P＜0.01). No apoptotic carcinoma cells were detected and bcl-2 postive cells were 2%~3% respectively in 2 kinds of NPC cells.CONCLUSION: Growth of NPC cells is enhanced by EBV infection and EBV-LMP1 expression, but no influence on expression of bcl-2 and apoptosis of NPC cells.     

CYP450 epoxygenase/EET pathway attenuates adipose inflammation of obese mice through HIF-1α

AIM To investigate the effects of cytochrome P450 （CYP450） epoxygenase/epoxyeicosatrienoic acid （EET） pathway on insulin resistance in obese mice, and to explore the possible mechanisms. METHODS High-fat diet-induced obesity model was established in C57BL/6Cnc mice, and the obese mice were randomly divided into 3 groups, including obesity group （treated with saline; n=10）, EET group （treated with 11,12-EET; n=10） and EET inhibitor 14,15-epoxyeicosa-5（Z）-enoic acid （EEZE） group （n=10）. Normal C57BL/6Cnc mice （n=10） treated with saline served as control. Protein expression of CYP2J2 （one of CYP450 epoxygenases） and hypoxia-inducible factor-1α （HIF-1α） was measured by Western blot. Vessel-like structure was detected by immunofluorescence staining. The serum levels of insulin, tumor necrosis factor-α （TNF-α）, interleukin （IL）-1β, IL-6 and monocyte chemoattractant protein-1 （MCP-1） were measured by ELISA. RESULTS In obese mice, homeostasis model assessment of insulin resistance （HOMA-IR） values were increased, the protein level of CYP2J2 was reduced, and the protein level of HIF-1α was increased in adipose tissues as compared with the controls （P<0.05）. The serum levels of MCP-1, IL-1β, IL-6 and TNF-α were also significantly increased in obese mice （P<0.05）. After treatment with 11, 12-EET, the HOMA-IR values were decreased compared with vehicle-treated obese mice, HIF-1α expression levels were decreased in the adipose tissue, and the serum levels of MCP-1, IL-1β, IL-6 and TNF-α were reduced （P<0.05）. Immunohistochemical results of adipose tissue from vehicle-treated obese mice showed a marked decrease in vessel-like structures （CD31-positive） compared with normal control mice （P<0.05）. EET treatment significantly increased the newly formed vessel-like structures in the visceral adipose tissues of obese mice as compared with vehicle-treated obese mice （P<0.05）. CONCLUSION High-fat diet-induced obesity and insulin resistance are closely related to the CYP450 pathway. Exogenous EETs effectively decrease obesity-induced insulin resistance possibly through pro-angiogenesis and attenuation of hypoxia and inflammation.     

Progress in roles of MNX1 antisense RNA 1 in malignant tumor

MNX1 antisense RNA 1 （MNX1-AS1） is a newly discovered long non-coding RNA （lncRNA）, which is highly dysregulated in various carcinomas and its expression level is closely related to the overall survival and prognosis of patients. MNX1-AS1 regulates the occurrence and development of carcinomas by endogenous competitive adsorption of miRNA, regulating cell cycle, inducing epithelial mesenchymal transformation and activating multiple signaling pathways. The in-depth study of the carcinogenesis of MNX1-AS1 is useful for the early diagnosis, targeted therapy and prognostic assessment of relevant carcinomas. This article reviews the roles of MNX1-AS1 in malignant tumor.     

长沙不同绿地对缓解热岛效应的作用

以长沙市学校、公园内的绿地作为研究对象,研究了不同生长发育植物、树冠郁闭度、植物覆盖率对城市热岛效应的影响,得出长势好的植物群落缓解热岛效应的作用大,郁闭度和绿地面积与减缓热岛效应的作用呈正相关。并根据长沙的绿化情况,提出了一些建议。