Ca~(2+)-CaM系统对野生苦菜耐盐抗氧化系统的调控

用两种从不同位点阻断Ca2+信号途径的抑制剂,即Ca2+螯合剂EGTA(乙二醇双四乙酸)(5 mmol/L)和CaM拮抗剂W7(N-氨乙基-5-氯-1-磺胺酰萘)(0.3 mmol/L),分别处理盐胁迫(0.5 mmol/L)下的野生苦菜幼苗,测定其抗氧化系统中酶的活性,H2O2、Pro和可溶性蛋白的含量。结果表明,EGTA(5 mmol/L)、W7(0.3 mmol/L)可降低超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)的活性,提高H2O2的含量,降低Pro和可溶性蛋白的含量,说明Ca2+-CaM系统与野生苦菜耐盐性密切相关。     

Ca2+-activated Cl- channels and pulmonary hypertension induced by high pulmonary blood flow

Pulmonary hypertension induced by high pulmonary blood flow involves a variety of complex mechanisms, including endothelial damage, pulmonary artery smooth muscle relaxation-contraction disorder and vascular remodeling. Besides, the factor of ion channels in pulmonary artery smooth muscle cells is also highly correlated to vasoconstriction. In recent years, many studies have shown that activation of Ca²⁺-activated Cl^- channels is responsible for the membrane depolarization of pulmonary artery smooth muscle cells, and plays an important role in the regulation of vascular tone and vasoconstriction. This article reviews the biophysical and pharmacological characteristics of Ca²⁺-activated Cl^- channels as well as the influence of Ca²⁺-activated Cl^- channels in high pulmonary blood flow-induced pulmonary hypertension.     

内毒素对肝脏p53表达及Ca2+浓度的影响

为探讨内毒素在致大鼠肝损伤过程中对肝脏p53表达及Ca2+浓度的影响,将48只SD大鼠随机分2组:Ⅰ组为NS对照组;Ⅱ组为ET致病组,2组大鼠分别于第3、4、8、12h每组各处死6只,采集肝脏分别用于p53表达的Western-blotting检测和Ca2+浓度的FCM检测。结果显示,Ⅱ组p53的表达明显高于Ⅰ组(P<0.01),且Ⅱ组一直呈上升趋势;Ⅱ组Ca2+的荧光指数明显高于Ⅰ组(P<0.01),且一直呈上升趋势。结果表明,ET能有效上调肝细胞p53蛋白的表达及Ca2+浓度。     

盐胁迫下赤霉素和钙对洒金柏种子萌发的影响

以洒金柏种子为材料,研究了NaCl胁迫下赤霉素和不同浓度的钙组合对其萌发效果的影响。结果表明,2.5 mg/L GA3+25 mmol/L Ca2+处理下的发芽率、发芽指数比对照分别提高了19%、51%,差异显著;经2.5 mg/LGA3+20 mmol/L Ca2+处理的种子活力指数比单独使用20 mmol/L的Ca2+提高了48.02%;而2.5 mg/L GA3+15mmol/L Ca2+处理的发芽势比对照提高了18.7%。同时盐胁迫下,洒金柏幼苗内可溶性糖及可溶性蛋白含量均增加,其中2.5 mg/L GA3+10 mmol/L CaCl2处理下的可溶性糖和2.5 mg/L GA3+15 mmol/L CaCl2处理下的可溶性蛋白含量增加幅度最为显著,分别比对照增加56.8%、120%。结果表明,GA3和Ca2+组合使用可缓解盐胁迫对洒金柏种子萌发的抑制作用。     

45Ca示踪技术研究三七提取物对细胞Ca2+内流与外溢的影响

采用45Ca同位素示踪技术,进行了三七提取物对大鼠内脏器官细胞Ca2+内流与外溢的影响研究。结果表明,从三七中提取的总皂苷和总黄酮对大鼠的心脏、肾脏、动脉平滑肌等内脏器官细胞钙通道具有一定的调控作用,既能阻滞Ca2+内流,也能促进已流入细胞内的Ca2+外溢。与总黄酮相比,总皂苷的作用更强,其调控作用可与阳性对照药物Verapamil相比。这一结果提示皂苷和黄酮提取物具有钙拮抗作用,可能是治疗冠心病的有效成分。     

Occurrence of prophage and historical perspectives associated with the dissemination of huanglongbing in mainland China

Huanglongbing (HLB), associated with a non-culturable bacterium ‘Candidatus Liberibacter asiaticus’ (CLas), is a highly destructive citrus disease with a long but poorly documented history in China. No effective treatment for HLB is available. The identification of new prophages in abundant CLas genomic sequence data provides new insights into both the diversity of CLas strains and HLB management. In this study, CLas populations from nine provinces were surveyed for the presence of prophage. Two major prophage typing groups (PTGs) were discovered to be associated with two different altitude regions: strains of CLas in PTG1 from high altitude regions (HAR) mainly contained prophage Type 1 only or Types 1 and 3, whereas strains of CLas in PTG2 from low altitude regions (LAR) mainly contained prophage Type 2. The discovery of these CLas population patterns provides evidence for independent origins of HLB in HAR and LAR. Guangdong province is the generally recognized domestic region of origin for HLB and is primarily responsible for the dissemination of HLB in LAR through transport of seedlings. Both Yunnan and Sichuan provinces are the probable regions of origin for HLB in HAR. PTG2 was further divided into two subgroups: PTG2-1, found in Guangdong, Fujian and Guangxi and PTG2-2, found in Jiangxi, Zhejiang and Hunan. These regions and prophage types are correlated with early and late introductions of HLB in LAR. These molecular analyses were supported by studying the history of the dissemination of HLB in historical documents.     

An additional life-history tactic of masu salmon: Migration of parr to coastal habitats

Alternative life-history tactics of masu salmon Oncorhynchus masou are well documented. Subsequent to the freshwater parr stage (age ≥ 1 + years), an anadromous form migrates to the sea after smolting, while a resident form matures without seaward migration. In addition to this typical migratory dimorphism, anecdotal reports based on field observations have indicated that some underyearling masu salmon use estuarine waters. However, no empirical evidence indicates saltwater utilisation and subsequent survival in the early parr stage. Here, we used otolith microchemistry to examine whether a portion of masu salmon parr in northern Japan enters coastal habitats. The otolith Sr:Ca ratios of most juveniles collected from six rivers had consistently low values, indicating that masu salmon parr inhabiting these rivers stay only in freshwater. In contrast, in individuals from a steep-gradient river the Sr:Ca ratios increased at about a 200-µm distance from the otolith core. These results suggest that some masu salmon parr might use brackish water or sea water temporarily. In addition, three masu salmon parr were found in another steep river where a culvert located only ten metres from the river mouth completely blocked upstream migration for spawning. The Sr:Ca ratios in these fish increased at about >200 µm from the otolith core, indicating the parr had immigrated to the non-natal river from the sea. Such flexible behaviour at an early life stage may contribute to the spatial expansion of masu salmon, and the movement could moreover help to stabilise its population dynamics.     

油桃果实顶腐形成原因分析

[目的]探讨油桃果实顶腐形成的原因。[方法]以中油5号油桃果实为试材,分别测定正常油桃与顶腐油桃果实中Ca含量;从顶腐油桃上分离纯化得到致病菌,采用CTAB法提取菌丝DNA,对其进行rDNA-ITS鉴定,利用NCBI在线Blast工具进行致病菌rDNAITS同源性比较。[结果]病果果实中Ca元素含量显著低于对照;腐烂坏死部位分离出2种不同类型菌丝,分别为弱寄生菌"黑变病"与"黑酵母菌"。[结论]油桃顶腐主要是由缺钙诱发后弱寄生菌侵染造成的。     

小型猪复合麻醉剂对大鼠不同脑区突触体Ca^2＋，Mg^2＋-ATP酶活性的影晌

探讨Ca2＋，Mg2＋-ATP酶与小型猪复合麻醉剂全麻作用的关系，以判断该酶是否为该制剂作用的靶位之一。选取84只SD大鼠，先随机抽取12只为对照组，其余随机均分为高剂量小型猪复合麻醉剂组（腹腔注射7．5mg／kg）和低剂量小型猪复合麻醉剂组（腹腔注射5mg／kg），每个剂量组又随机均分为麻醉组、恢复I组和恢复Ⅱ组等3个亚纽。对照组腹腔注射生理盐水10mL／kg，5min后断头取材；麻醉组、恢复I组和恢复Ⅱ组分别在翻正反射消失即刻、翻正反射恢复即刻和大鼠可直线爬行后断头取材，在生理盐水冰面上取脑，用4℃生理盐水将脑上的血迹冲洗干净，迅速分离双侧大脑皮层、海马、小脑、脑干、丘脑，立即液氮冷冻。制备脑粗突触体，采用比色法测定ca2＋，Mg2-ATP酶活性。结果表明，小型猪复合麻醉剂的全麻作用与抑制小脑和丘脑突触体Ca2＋，Mg2＋-ATP酶活性相关，此酶可能是小型猪复合麻醉剂全麻作用的靶位之一。     

盐胁迫对碱茅幼苗叶片内源激素、NAD激酶及Ca2+-ATPase的效应

为了研究盐渍生境对盐生植物碱茅Puccinellia chinampoensis体内部分信号分子的影响,采用不同浓度NaCl溶液处理碱茅植株,对幼苗叶片中部分信号分子及相关蛋白测定和分析.结果发现,低盐下碱茅无胁迫反应,高盐胁迫下,碱茅脱落酸(ABA)含量升高,生长素(IAA)、赤霉素(GA)含量均下降,细胞分裂素(ZR)含量趋于稳定;碱茅NAD激酶(NADKase)活性升高,提高代谢调节能力;同时Ca2 -ATPase活性增加,是对盐胁迫引起Ca2 浓度升高而做出的胁迫反应.表明了碱茅通过胞间信号相对含量的变化,调节NADKase活性、Ca2 -ATPase活性,提高耐盐能力.