Restoration of CA2+-inhibited oxidative phosphorylation in cardiac mitochondria by mitochondrial Ca2+ unloading

Mitochondria, the major source of cellular ATP, display high vulnerability to metabolic stress, in particular to excessive Ca²⁺ loading. Here, we show that Ca²⁺-inhibited mitochondrial ATP generation could be restored through stimulated Ca²⁺ discharge from mitochondrial matrix. This was demonstrated using a Ca²⁺ ionophore or through Na⁺/Ca²⁺ exchange-mediated decrease of mitochondrial Ca²⁺ load. Furthermore, diazoxide, a mitochondrial potassium channel opener, which maintained mitochondrial Ca²⁺ homeostasis, also restored Ca²⁺-inhibited ATP synthesis and preserved the structural integrity of Ca²⁺-challenged mitochondria. Thus, under conditions of excessive mitochondrial Ca²⁺ overload targeting mitochondrial Ca²⁺ transport pathways restores oxidative phosphorylation required for vital cellular processes. This study, therefore, identifies an effective strategy capable to rescue Ca²⁺-disrupted mitochondrial energetics.     

水稻早世代稳定718群体的获得及分析

水稻早世代稳定现象是近年来发现的一种特殊现象,其中多个早世代稳定群体是在利用来自水稻双胚苗中的多倍体与不同二倍体材料杂交得到的。本实验利用一自然突变的多倍体,与二倍体水稻太平369杂交,F_1代大部分为非整倍体,其中5株为二倍体,收取这5株二倍体上的种子,种下得到 F_2群体且定名为718群体。该群体田间观察整齐一致,经过对田间调查数据和微卫星结果的分析,表明该群体为一早世代稳定群体。     

长江三峡地区上震旦统稳定同位素异常及地层意义

三峡地区广泛发育的上震旦统,及下伏的南沱组和古城组冰碛层,有良好的生物地层控制及全球对比意义。新秭归城附近的雾河剖面,自南沱组顶部到水井沱组下部出露有利于化学地层学研究的一系列碳酸盐岩沉积,对这一剖面的碳,氧,锶同位素研究发现：1）碳,锶和氧同位素在陡山沱组顶部到灯影组底部存在明显异常;2）碳同位素在寒武系-前寒武系界线附近有负异常;3）碳同位素和锶同位素在剖面上的演化具有全球对比意义;4）陡山沱组顶部到灯影组底部的碳,锶同位素异常,与可能存在末远古纪的冰期,即所谓的“后Marinoan冰期”有关。     

角堇与大花三色堇染色体核型分析

以2份角堇与4份大花三色堇自交系为试验材料,采用染色体常规压片方法,观察和分析了它们的细胞染色体数目、相对长度、平均臂比等核型指标,以明确两种植物细胞学特点,为分类以及育种提供理论依据。结果表明:(1)2份角堇自交系染色体数目均为2n=2x=26,染色体基数为x=13,染色体核型公式分别为2n=2x=26=8m+12sm+6st、2n=2x=26=4m+16sm+6st,核型不对称系数为67.20%~70.10%,核型分类均属于3B。(2)4份大花三色堇自交系均为四倍体,其中2份(EYO-1-2-1-4、DSRFY-1-1-2)染色体数目为44,核型公式为2n=4x=44=4m+16sm+6st、2n=4x=44=16m+24sm+4st;2份(G10-1-3-1-4、XXL-YB-1-1-1-1)染色体数目为48,核型公式分别为2n=4x=48=8m+20sm+20st、2n=4x=48=4m+36sm+8st,核型不对称系数为66.74%~71.77%,核型分类属于2B、3B。     

Revealing potential bridge vectors for BTV and SBV: a study on Culicoides blood feeding preferences in natural ecosystems in Spain

Several species of Culicoides (Diptera: Ceratopogonidae) are vectors of pathogens, such as the bluetongue (BTV) and Schmallenberg (SBV) viruses, which cause important diseases in domestic and wild ruminants. As wild ruminants can contribute to overwintering and epizootics of both diseases, knowledge of the host‐feeding behaviour of Culicoides in natural ecosystems is important to better understand their epidemiology. Blood‐engorged Culicoides females trapped in natural areas inhabited by different wild ruminant species were genetically analysed to identify host species. The origin of bloodmeals was identified in 114 females of 14 species of Culicoides. A total of 104 (91.1%) Culicoides fed on mammals and 10 (8.9%) on birds. The most abundant host identified was red deer (66.7%), followed by humans (13%) and fallow deer (6.1%). Eleven of the 14 species of Culicoides fed exclusively on mammalian hosts. Among them, five are mammalophilic species considered to be important BTV and/or SBV vectors. The results of the present study confirm that Culicoides imicola, Culicoides obsoletus, Culicoides scoticus, Culicoides pulicaris and Culicoides punctatus fed on wild ruminants, and therefore support the hypothesis that these species can act as bridge vectors by facilitating the circulation of pathogens between wild and domestic ruminant communities.     

大湄公河次区域薇甘菊的防控技术

薇甘菊是大湄公河次区域的重要恶性入侵杂草,其种群跨境入侵扩张备受区域各国政府的高度重视和社会广泛关注。2011年以来在我国相关农业科研机构、团队和专家的科技支撑下,中国云南与周边五国科研机构成立“大湄公河次区域植物保护工作组”。本文简要介绍工作组围绕该入侵杂草在生态异质性条件下种群扩展与灾变过程的预警监测、阻截防控带建设、替代控制与选择性除草剂协同应用取得的阶段性成效,为积极主动融入国家“一带一路”倡议的实施,服务于中国云南的经济国境线、绿色国境线和生态国境线发挥建设性作用。     

黄檗的胚胎学研究

黄檗(PhellodendronamurenseRupr.)为雌雄异株植物,雌花中有退化的雄蕊原基,雄花中有退化的心皮。黄檗花药壁发育为基本型。腺质绒毡层,细胞双核或多核。小孢子母细胞减数分裂为同时型。小孢子四分体为四面体型排列,成熟花粉有2-细胞和3-细胞型2种。子房5室,中轴胎座、倒生胚珠、具珠柄珠孔塞、双珠被、厚珠心和多孢原细胞。大孢子四分体为直线型、少数为“T”型排列,合点端的一个为功能性大孢子。蓼型胚囊,双受精属于有丝分裂前配子融合类型。胚的发育为藜型,核型胚乳。后期胚乳组织外层形成“次生胚乳”,原胚乳细胞逐渐退化解体。     

溶藻细菌FS1的溶藻效果与机制初探

近年来,由水体富营养化引发的蓝藻水华频繁暴发,对水体生态系统平衡产生了重大影响,给人类健康也带来严重威胁。生物法除藻具有高效性、环境友好等优点,因此,如果能获得具有较高溶藻效率的溶藻细菌,选择生物法除藻更为理想。从菏泽一富营养化池塘分离得到1株溶藻细菌FS1,经16S rDNA测序分析鉴定为芽胞杆菌属。实验以铜绿微囊藻为研究对象,采用血球计数板法计算反应前后藻细胞的浓度,对不同生长阶段溶藻细菌FS1的溶藻效果进行了探究。停滞期、对数期、稳定期和衰亡期的除藻率分别为7.1%、24.3%、57.0%和45.5%,结果表明,处于稳定期的FS1对铜绿微囊藻的去除效果最佳。细菌溶藻方式的研究结果表明,溶藻细菌是通过分泌溶藻物质间接溶解藻细胞。     

右旋糖酐40制备过程中细菌内毒素含量的影响因素

右旋糖酐40生产中分离纯化采用乙醇沉淀和超滤方法,将细菌内毒素作为分离纯化的一项指标,对影响因素进行探究,将细菌内毒素含量引入右旋糖酐40原料药产品标准,并且达到国际标准。随着乙醇浓度的增加,相应沉淀产品的细菌内毒素含量逐渐降低;在乙醇分步沉淀中,随着乙醇浓度逐级提高,分离产品的细菌内毒素含量也在降低。分离纯化用水和环境因素均会影响右旋糖酐40分离纯化的细菌内毒素指标。乙醇沉淀分离纯化的右旋糖酐40产品,细菌内毒素含量均<6.00 EU/g,最低含量<3.00 EU/g,优于国际标准(≤10 EU/g),重均分子量和分子量均符合《中国药典》质量标准。100 kDa+20 kDa二膜组合超滤分离纯化的右旋糖酐40的细菌内毒素含量可以达到10 EU/g以下。100 kDa+20 kDa+50 kDa三膜组合超滤分离纯化,右旋糖酐40的细菌内毒素含量达到3 EU/g以下,重均分子量及分子量分布达到《中国药典》标准。改进右旋糖酐40生产工艺,提高产品品质,细菌内毒素含量引入右旋糖酐40原料药质量指标,使其达到和超过国际最高质量标准。