甘肃省被子植物分布新记录

报道了甘肃省分布的玄参科(Scrophulariaceae)水茫草属(Limosella Linn.)1个新记录属,以及玄参科(Scrophulariaceae)、木兰科(Magnoliaceae)、蓼科(Polygonaceae)、胡颓子科(Elaeagnaceae)、百合科(Liliaceae)5个新记录种——水茫草(Limosella aquatica Linn.)、峨眉含笑(Michelia wilsonii Finet et Gagnep.)、叉分蓼(Polygonum divaricatum L.)、棱果沙棘(Hippophae goniocarpa Y.S.Lian et al.ex SwensonBartish)、青海黄精(Polygontum qinghaiense Z.L.Wu et Y.C.Yang)。其中,峨眉含笑是国家二级重点保护野生植物。     

河西走廊春季不同盐碱土壤中微生物数量、酶活性与理化因子的关系

【目的】揭示盐碱土壤微生物量与土壤因子间的关系。【方法】选择河西走廊不同盐碱程度的11个样点在春季进行采样,研究了土壤的微生物数量、酶活和理化性质,并对其进行方差分析、简单相关分析、逐步回归分析和主成分分析。【结果】河西地区原生盐碱地、次生盐碱地与农田土在土壤理化性质和土壤微生物数量等方面均有差异;河西地区土壤较贫瘠,土壤微生物数量较低,且分布有规律性,即原生盐碱土<次生盐碱土<农田土;放线菌、真菌、碱性磷酸酶、脲酶和有效磷5个因子是引起土壤微生物数量、酶活性与理化因子之间相关性的主要因素。【结论】结果证实河西地区盐碱土壤中磷的循环很大程度上影响着土壤微生物数量。     

Membrane Skeletal Proteins and Their Integral Membrane Protein Anchors are Targets for Tyrosine and Threonine Kinases in Euglena

ABSTRACT. Proteins of the membrane skeleton of Euglena gracilis were extensively phosphorylated in vivo and in vitro after incubation with [³²P]-orthophosphate or γ-[³²P] ATP. Endogenous protein threonine/serine activity phosphorylated the major membrane skeletal proteins (articulins) and the putative integral membrane protein (IP39) anchor for articulins. The latter was also the major target for endogenous protein tyrosine kinase activity. A cytoplasmic domain of IP39 was specifically phosphorylated, and removal of this domain with papain eliminated the radiolabeled phosphoamino acids and eliminated or radically shifted the PI of the multiple isoforms of IP39. In gel kinase assays IP39 autophosphorylated and a 25 kDa protein which does not autophosphorylate was identified as a threonine/serine (casein) kinase. Plasma membranes from the membrane skeletal protein complex contained threonine/serine (casein) kinase activity, and cross-linking experiments suggested that IP39 was the likely source for this membrane activity. pH optima, cation requirements and heparin sensitivity of the detergent solubilized membrane activity were determined. Together these results suggest that protein kinases may be important modulators of protein assembly and function of the membrane skeleton of these protistan cells.     

骨软骨复合支架的研究进展

软骨的修复是当前医学界十分棘手的难题,人们采取若干手段均收效甚微。由于软骨缺损时,其下的软骨下骨常出现硬化、退变,而新生软骨是无法与病变的软骨下骨进行整合的,所以在修复软骨的同时,必须重视软骨下骨的修复。近十几年来,人们开始发明和利用各种骨软骨复合支架,进行同时修复软骨与软骨下骨的动物实验研究。在正常骨软骨组织中,软骨与软骨下骨被钙化层所相连,此外钙化层也将软骨与软骨下骨分隔在不同的生存环境中。根据仿生学原理,人们又设计出一种带有隔离层的新型骨软骨复合支架,并取得了较为理想的实验结果。本文就国内外骨软骨复合支架的研完进展作一综述。     

“三生”空间视角下土地利用转型的生态环境效应及驱动力——以甘肃省为例

中国社会经济快速转型背景下土地利用变化所引发的环境问题被广泛关注。以土地利用现状遥感监测数据和统计资料为数据源,借助ArcGIS和SIMCA-P软件平台,基于"三生"空间视角,通过生态环境质量指数测度了1980—2018年甘肃省土地利用转型的生态环境效应,并运用偏最小二乘法揭示生态环境质量演变的驱动机制。研究发现:(1)"三生"空间结构演化和地域分异显著。生产、生活空间集中分布于河西走廊、陇中和陇东黄土高原并呈扩张态势;生态空间主要分布于陇南山地、甘南高原、祁连山地和河西走廊以北地带且整体呈缩减趋势;生产、生活空间的增长源于对生态空间的侵占。(2)生态环境质量改善和恶化趋势并存,整体上经历了先下降后上升的"U"形演化过程;空间上呈"东南高-西北低"的分布特征,空间格局演化具有明显的集聚性。(3)生态建设、科技进步等对生态环境改善具有明显的促进作用;而人口增加、社会消费水平提升在一定程度上加剧了生态环境压力;对外贸易对生态环境的影响具有双面性。     

Indoor and outdoor winter activity of Culicoides biting midges,vectors of bluetongue virus,in Italy

Indoor and outdoor winter activity of Culicoides spp. (Diptera: Ceratopogonidae) in central Italy was investigated in order to evaluate whether indoor activity might account for the overwintering of bluetongue virus, as has been hypothesized by some authors. Weekly Culicoides collections were performed at three farms over three consecutive winter seasons. At each farm, two black‐light traps were operated simultaneously, indoors and outdoors. Culicoides were identified using both morphological and molecular means. The Culicoides obsoletus group accounted for 98.2% of sampled specimens. Within this group, C. obsoletus s.s. accounted for 56.8% and Culicoides scoticus for 43.2% of samples. Nulliparous, parous and engorged females were caught throughout the entire winter, both indoors and outdoors. At times, indoor catch sizes outnumbered outdoor collections. A significant inverse correlation was found between minimum temperature and the proportion of indoor Culicoides of the total midge catch, thus indicating that lower outdoor temperatures drive Culicoides midges indoors. High rates of engorged females were recorded indoors, possibly as the result of the propensity of C. obsoletus females to feed indoors. Higher proportions of parous females were found in indoor than in outdoor catches, indicating higher survival rates indoors and, consequently, higher vectorial capacities of midges sheltering indoors compared with those remaining outdoors.     

Adiponectin and colon cancer: evidence for inhibitory effects on viability and migration of human colorectal cell lines

Exogenous hydrogen peroxide (H₂O₂) induces oxidative stress and apoptosis in cancer cells. This study evaluated the antiapoptotic effects of pan-caspase and caspase-3, -8, or -9 inhibitors on H₂O₂-treated Calu-6 and A549 lung cancer cells in relation to reactive oxygen species (ROS) and glutathione (GSH). Treatment with 50–500 μM H₂O₂ inhibited the growth of Calu-6 and A549 cells at 24 h and induced apoptosis in these cells. All the tested caspase inhibitors significantly prevented cell death in H₂O₂-treated lung cancer cells. H₂O₂ increased intracellular ROS levels, including that of O ₂ ^·? , at 1 and 24 h. It also increased the activity of catalase but decreased the activity of SOD. In addition, H₂O₂ triggered GSH deletion in Calu-6 and A549 cells at 24 h. It reduced GSH levels in Calu-6 cells at 1 h but increased them at 24 h. Caspase inhibitors decreased O ₂ ^·? levels in H₂O₂-treated Calu-6 cells at 1 h and these inhibitors decreased ROS levels, including that of O ₂ ^·? , in H₂O₂-treated A549 cells at 24 h. Caspase inhibitors partially attenuated GSH depletion in H₂O₂-treated A549 cells and increased GSH levels in these cells at 24 h. However, the inhibitors did not affect GSH deletion and levels in Calu-6 cells at 24 h. In conclusion, H₂O₂ induced caspase-dependent apoptosis in Calu-6 and A549 cells, which was accompanied by increases in ROS and GSH depletion. The antiapoptotic effects of caspase inhibitors were somewhat related to the suppression of H₂O₂-induced oxidative stress and GSH depletion.     

Short-Term In Vitro Culture and Molecular Analysis of the Microsporidian, Enterocytozoon bieneusi

ABSTRACT. The microsporidium, Enterocytozoon bieneusi , causes a severe, debilitating, chronic diarrhea in patients with the acquired immunodeficiency syndrome. Specific diagnosis of intestinal microsporidiosis, especially due to Enterocytozoon , is difficult and there is no known therapy that can completely eradicate this parasite. Preliminary studies indicate that a short term (about 6 months) in vitro culture of this parasite yielding low numbers of spores, may be established by inoculating human lung fibroblasts and/or monkey kidney cell cultures with duodenal aspirates and or biopsy from infected patients. The cultures may subsequently be used for the isolation and molecular analysis of parasite DNA.