Phenotype–genotype analysis in two Chinese families with Liddle syndrome

The families with Liddle syndrome show marked phenotypic variation in blood pressure, serum potassium and other clinical manifestations. Here we analyzed the correlation of genotype–phenotype in two Chinese families with Liddle syndrome. The sequence of C-terminus of SCNN1B and SCNN1G were screened in the two families with likely Liddle syndrome. In addition to hypertension and hypokalemia, one of the two pedigrees had sudden death in their family members, so the exons of 428 reported genes-related to cardiovascular diseases were screened as well in the family. A heterozygous βR566X nonsense mutation was found in the proband-1 in the first pedigree, and the proband’s sister and father. They showed mild phenotype with hypertension under control. In contrast, two of the four previous studies report that the mutation causes severe phenotype. A heterozygous βR597PfrX607 frameshift mutation was identified in the proband-2 in the second pedigree, showing malignant phenotype including resistant hypertension, hypokalemia, higher PRA and plasma angiotensin II levels. Both the proband-2 and the proband-2’s father had sudden death in their twenties, but no meaningful mutations were found by screening of the exons in 428 cardiovascular disease-related genes. However, the same mutation has been related to moderate phenotype in previous studies. Our results confirmed that the phenotypes of Liddle syndrome are varied significantly even with the same mutation. The mechanisms why the same mutation causes very different phenotype need to be explored because intervention of these modifiers may change the disease course and prognosis accordingly.     

动脉粥样硬化中单核细胞膜流动性研究

为研究动脉粥样硬化中单核细胞膜流动性的变化,本实验选用20只新西兰白兔建立动物粥样硬化模型,提取模型组与对照组兔外周血中单核细胞,通过荧光漂白恢复技术检测单核细胞膜流动性,并结合动脉粥样硬化动物模型病理切片揭示其与动脉粥样硬化相关性。结果显示动物动脉粥样硬化模型建立成功,模型组单核细胞膜的荧光恢复率和扩散系数均低于对照组。本研究揭示了单核细胞细胞膜的流动性与动脉粥样硬化的发生有关,为今后深入探究单核细胞与动脉粥样硬化关系提供实验基础。     

人为干扰对川西金凤山楠木次生林群落结构和物种多样性的影响

物种多样性是群落功能复杂性和稳定性的重要量度指标,人为干扰对森林群落的影响可以通过群落结构和物种多样性的变化直接表现出来,不同干扰强度下群落结构和多样性特征不同。金凤山景区主要有选择性采伐和旅游活动这两种人为干扰形式,为研究不同强度人为干扰对金凤山楠木次生林群落的多样性和稳定性的影响,在实地充分考察的基础上,将干扰强度划分为3个等级:重度干扰:紧靠核心景区0—40 m,中度干扰:距离核心景区40—80 m,轻度干扰:远离核心景区80—120 m,采用典型取样法,调查3种不同强度的人为干扰对群落不同林分层次的物种组成、群落结构和多样性的影响,采用物种丰富度指数S值、Shannon-Wienner指数H值、Simpson优势度指数D值和均匀度指数Jsw值来综合衡量群落的物种多样性水平。结果表明:(1)在总面积为3600 m2的9个样地中,共记录到维管束植物155种,隶属于69科136属;物种数随着人为干扰强度增加呈递减趋势,轻度、中度和重度干扰下群落的物种数依次为:113种,88种,77种。(2)从群落结构上看,轻度和中度干扰下乔木个体多分布在小中径级(4胸径DBH20 cm)和低中高度级(5高度H13 m);而重度干扰下乔木个体多分布在小径级(DBH8 cm)、大径级(DBH≥28 cm)和低高度级(3H7 m)、高高度级(H≥15 m),其群落结构与轻度和中度干扰下乔木层的群落结构明显不同。(3)受不同强度人为干扰的楠木次生林群落各物种多样性指数大小排序为:轻度干扰中度干扰重度干扰,S值、H值和Jsw随着人为干扰强度的增加而降低。     

Phosphorus,Nitrogen and Chlorophyll-a Are Significant Factors Controlling Ciliate Communities in Summer in the Northern Beibu Gulf,South China Sea

Ciliates (protozoa) are ubiquitous components of plankton community and play important roles in aquatic ecosystems in regards of their abundance, biomass, diversity and energy turnover. Based on the stratified samples collected from the northern Beibu Gulf in August 2011, species composition, abundance, biomass, diversity and spatial pattern of planktonic ciliates were studied. Furthermore the main environmental factors controlling ciliate communities were determined. A total of 101 species belonging to 44 genera and 7 orders (i.e., Oligotrichida, Haptorida, Euplotida, Sessilida, Pleurostomatida, Scuticociliatida and Tintinnida) were identified. The variation of ciliate communities was significant at horizontal level, but that was not at vertical level. Based on cluster analysis, ciliate communities were divided into three main groups. Redundancy analysis (RDA) revealed that Group A, existing in the waters with higher concentration of phosphorus and nitrogen, was dominated by Tintinnidium primitivum. Group B in the waters with lower temperature and chlorophyll-a concentration, was dominated by Leegaardiella ovalis. Group C, existing in the waters with higher temperature and chlorophyll-a concentration, was dominated by large Strombidium spp. and Mesodinium rubrum. Combining multiple analytic methods, our results strongly supported that phosphorus, nitrogen and chlorophyll-a were the most significant factors affecting the ciliate communities in the northern Beibu Gulf in summer. Concentration of phosphorus and nitrogen primarily influenced ciliate biomass, implying a potential impact of eutrophication on ciliate growth. The correlation with chlorophyll-a concentration, on one hand indicate the response of ciliates to the food availability, and on the other hand, the ciliates containing chloroplasts or endosymbionts may contribute greatly to the chlorophyll-a.     

Distribution, Feeding and Body Condition of Four Small Fish Species in the Near-shore and Central Areas of Liangzi Lake, China

Synopsis Small fish abundance is usually high in heavily vegetated habitats in Yangtze lakes, China. Visual and swimming barriers created by dense macrophytes beds could reduce feeding efficiency and growth of small fishes. We tested the hypothesis that small fishes in habitats with dense macrophytes would show decreased feeding efficiency and reduced growth rates by comparing feeding efficiency (measured as the relative weight of fore-gut contents), total length, and condition factor of four small young-of-the-year fishes collected in the near-shore (heavily vegetated) and central (less vegetated) areas of Liangzi Lake. Feeding efficiency, total length, or condition factor were each significantly reduced in the near-shore area compared with the central area for Ctenogobius giurinus, Pseudorasbora parva and Carassius auratus auratus. This supports our hypothesis that vegetation abundance may mediate feeding efficiency and growth of small fishes. Although Hypseleotris swinhonis did not show significant decreases in feeding efficiency or growth in the near-shore area, there was not any reversed tendency, i.e. increased feeding rate or growth in the near-shore area compared to the central area. Yibo Cui: Deceased     

MOF Template‐Directed Fabrication of Hierarchically Structured Electrocatalysts for Efficient Oxygen Evolution Reaction

The ever‐increasing demand for clean and renewable power sources has sparked intensive research on water splitting to produce hydrogen, in which the exploration of electrocatalysts is the central issue. Herein, a new strategy, metal–organic framework template‐directed fabrication of hierarchically structured Co₃O₄@X (X = Co₃O₄, CoS, C, and CoP) electrocatalysts for efficient oxygen evolution reaction (OER) is developed, where Co₃O₄@X are derived from cobalt carbonatehydroxide@zeolitic‐imidazolate‐framework‐67 (CCH@ZIF‐67). Unique hierarchical structure and synergistic effect of resulting catalysts endow abundant exposed active sites, facile ion diffusion path, and improved conductivity, being favorable for improving catalytic activity of them. Consequently, these derivatives Co₃O₄@X reveal highly efficient electrocatalytic performance with long‐term durability for the OER, much superior to previously reported cobalt‐based catalysts as well as the Ir/C catalyst. Particularly, Co₃O₄@CoP exhibits the highest electrocatalytic capability with the lower overpotential of 238 mV at the current density of 10 mA cm^?2. Furthermore, Co₃O₄@X can also efficiently catalyze other small molecules through electro‐oxidation reaction (e.g., glycerol, methanol, or ethanol). It is expected that the strategy presented here can be extended to the fabrication of other composite electrode materials with hierarchical structures for more efficient water splitting.