昆虫寄主选择行为的进化机制

昆虫的寄主选择行为受到遗传、可传承的环境因素或学习行为的调控。尽管大量实验已证实昆虫寄主选择中的遗传变异,但在实际中很难将其与温度、营养、条件作用和可传承的环境因素的作用区别开来。一些报道已证实可传承的环境因素会影响昆虫的寄主选择行为。幼虫期和成虫期对寄主的经历可以改变该虫态的取食和产卵寄主偏嗜行为。虽然巴甫洛夫条件反射和神经组织移植实验初步揭示了幼虫经历对成虫气味选择行为的影响,但寄主选择行为中的前印象条件作用尚需进一步验证。在城市垃圾生态系统中,杂食性的蝇类的取食和产卵选择行为较腐食性的蝇类更易受到学习经历的重塑。     

多数据库分析肝细胞癌中GLTPD2的表达及临床意义

人类糖脂转运结构域2蛋白(GLTPD2)是糖脂转运蛋白(GLTP)家族的一个新成员.本研究的目的在于通过生物信息学分析,探究GLTPD2在肝细胞癌(LIHC)中的表达及临床意义.利用TCGA数据库的第三方在线工具LinkedOmics分析GLTPD2的表达与LIHC各临床病理特征的关系;利用Ualcan工具分析GLTP...     

复合凝乳酶对功能性消化不良儿童营养状态和摄食行为的影响

目的:观察复合凝乳酶胶囊对不同亚型功能性消化不良儿童临床表现、营养状态和摄食行为的影响及安全性。方法:以2017年8月至2018年9月在湖北省妇幼保健院儿童消化内科就诊的功能性消化不良(Functional dyspepsia,FD)儿童为研究对象进行问卷调查,观察治疗前和复合凝乳酶治疗2 w后患儿临床症状变化及药物相关不良反应的发生情况,监测患儿身高和体重,进行膳食情况的调查。结果:共163例儿童纳入研究,发生餐后不适综合征(Postprandial distress syndrome, PDS)66例,上腹痛综合征(Epigastric pain syndrome, EPS)97例。治疗前,PDS组儿童症状总分明显高于EPS儿童(6.9±2.7 vs 3.6±1.7,t=5.90,P=0.00)。PDS组儿童WAZ、WHZ、HAZ、身高别体质量Z值(weight for height Z score,WHZ)、年龄别身高Z值(height for age Z score,HAZ)、年龄别体质量Z值(weight for age Z score,WAZ)、体质量指数(body mass index,BMI)、膳食多样化分数(Dietary diversity score, DDS)均明显低于EPS组(P均0.05)。治疗2 w后,PDS儿童症状总分明显降低(P=0.00),改善程度依次为:厌食早饱腹痛嗳气恶心腹胀。EPS儿童症状总分无明显变化(P=0.11)。PDS儿童WAZ、WHZ、DDS均有明显升高(P均0.05)。EPS儿童DDS无明显变化(t=0.22,P=0.30)。研究期间未见明显药物相关不良反应。结论:复合凝乳酶胶囊可改善PDS患儿的临床症状、营养状态和膳食多样性,且安全性高。     

Lacking chloroplasts in guard cells of crumpled leaf attenuates stomatal opening: both guard cell chloroplasts and mesophyll contribute to guard cell ATP levels

Controversies regarding the function of guard cell chloroplasts and the contribution of mesophyll in stomatal movements have persisted for several decades. Here, by comparing the stomatal opening of guard cells with (crl‐ch) or without chloroplasts (crl‐no ch) in one epidermis of crl (crumpled leaf) mutant in Arabidopsis, we showed that stomatal apertures of crl‐no ch were approximately 65–70% those of crl‐ch and approximately 50–60% those of wild type. The weakened stomatal opening in crl‐no ch could be partially restored by imposing lower extracellular pH. Correspondingly, the external pH changes and K⁺ accumulations following fusicoccin (FC) treatment were greatly reduced in the guard cells of crl‐no ch compared with crl‐ch and wild type. Determination of the relative ATP levels in individual cells showed that crl‐no ch guard cells contained considerably lower levels of ATP than did crl‐ch and wild type after 2 h of white light illumination. In addition, guard cell ATP levels were lower in the epidermis than in leaves, which is consistent with the observed weaker stomatal opening response to white light in the epidermis than in leaves. These results provide evidence that both guard cell chloroplasts and mesophyll contribute to the ATP source for H⁺ extrusion by guard cells.     

Glucose inhibits root meristem growth via ABA INSENSITIVE 5, which represses PIN1 accumulation and auxin activity in Arabidopsis

Glucose functions as a hormone‐like signalling molecule that modulates plant growth and development in Arabidopsis thaliana. However, the role of glucose in root elongation remains elusive. Our study demonstrates that high concentrations of glucose reduce the size of the root meristem zone by repressing PIN1 accumulation and thereby reducing auxin levels. In addition, we verified the involvement of ABA INSENSITIVE 5 (ABI5) in this process by showing that abi5‐1 is less sensitive to glucose than the wild type, whereas glucose induces ABI5 expression and the inducible overexpression of ABI5 reduces the size of the root meristem zone. Furthermore, the inducible overexpression of ABI5 in PIN1::PIN1‐GFP plants reduces the level of PIN1‐GFP, but glucose reduces the level of PIN1‐GFP to a lesser extent in abi5‐1 PIN1::PIN1‐GFP plants than in the PIN1::PIN1‐GFP control, suggesting that ABI5 is involved in glucose‐regulated PIN1 accumulation. Taken together, our data suggest that ABI5 functions in the glucose‐mediated inhibition of the root meristem zone by repressing PIN1 accumulation, thus leading to reduced auxin levels in roots.     

“甘蔗复合群＂能源植物遗传育种研究进展

“甘蔗复合群”是一类极具生物能源开发潜力的禾本科C4植物。近年来由于世界能源危机的影响和植物遗传育种研究的发展,国内外学者对“甘蔗复合群”植物资源评价和能源育种研究越来越重视。本文介绍了“甘蔗复合群”的基本概念、属种分类及核心类群等研究背景。同时以甘蔗属和芒属核心资源为例,从“甘蔗复合群”能源植物遗传育种的角度综述了国内外相关研究进展。旨在总结前人的理论研究成果和杂交育种实践经验,探讨相关类群在植物系统分类和种质资源利用中存在问题与对策,为我国“甘蔗复合群”能源植物的应用基础研究和产业化开发利用提出建议。     

MiR-506 inhibits PRRSV replication in MARC-145 cells via CD151

Porcine reproductive and respiratory syndrome (PRRS) is one of the most economically important diseases of swine, which is caused by PRRS virus (PRRSV). CD151, one of PRRSV entry mediators, determines the cell susceptibility for PRRSV. Emerging evidence indicates that the host microRNAs (miRNAs) play key roles in modulating virus infection and viral pathogenesis. In the present study, targeting porcine CD151 miRNAs were identified, and their function during PRRSV infection in MARC-145 cells was further verified. We found that miR-506 could directly target porcine CD151 3′-UTR mRNA by luciferase reporter assay. Overexpression of miR-506 significantly decreased CD151 expression at both mRNA and protein levels. Furthermore, overexpression of miR-506 reduced cellular PRRSV replication and virus release in MARC-145 cells. Our results suggested that miR-506 could inhibit PRRSV replication by directly targeting PRRSV receptor of CD151 in MARC-145 cells. However, the molecular mechanisms of miR-506 and its function in vivo need further investigation.     

Epigallocatechin-3-gallate (EGCG) as a pro-osteogenic agent to enhance osteogenic differentiation of mesenchymal stem cells from human bone marrow: an in vitro study

The proliferation and osteogenic capacity of mesenchymal stem cells (MSCs) needs to be improved for their use in cell-based therapy for osteoporosis. (?)-Epigallocatechin-3-gallate (EGCG), one of the green tea catechins, has been widely investigated in studies of osteoblasts and osteoclasts. However, no consensus on its role as an osteogenic inducer has been reached, possibly because of the various types of cell lines examined and the range of concentrations of EGCG used. In this study, the osteogenic effects of EGCG are studied in primary human bone-marrow-derived MSCs (hBMSCs) by detecting cell proliferation, alkaline phosphatase (ALP) activity and the expression of relevant osteogenic markers. Our results show that EGCG has a strong stimulatory effect on hBMSCs developing towards the osteogenic lineage, especially at a concentration of 5 μM, as evidenced by an increased ALP activity, the up-regulated expression of osteogenic genes and the formation of bone-like nodules. Further exploration has indicated that EGCG directes osteogenic differentiation via the continuous up-regulation of Runx2. The underlying mechanism might involve EGCG affects on osteogenic differentiation through the modulation of bone morphogenetic protein-2 expression. EGCG has also been found to promote the proliferation of hBMSCs in a dose-dependent manner. This might be associated with its antioxidative effect leading to favorable amounts of reactive oxygen species in the cellular environment. Our study thus indicates that EGCG can be used as a pro-osteogenic agent for the stem-cell-based therapy of osteoporosis.     

油茶良种‘华硕’的组织培养及高效生根

以油茶‘华硕’带芽茎段为外植体,研究植物生长调节剂、珍珠岩对其快速繁殖及试管苗生根的影响。结果表明：茎段腋芽萌发的最佳培养基为：MS＋2.0 mg·L^-1 6-BA＋0.1 mg·L^-1 IAA,萌发率达88.68%;最佳继代增殖培养基为：WPM＋3.0 mg·L^-1 6-BA＋0.01 mg·L^-1 IBA＋6.0 mg·L^-1 GA3,增殖系数可达11.27;最佳壮苗伸长培养基为：WPM＋0.05 mg·L^-1 IAA＋6.0 mg·L-1GA3;最佳生根培养基为：1/2MS＋1.0 mg·L^-1 IBA＋50 g·L^-1珍珠岩,生根率95.83%。炼苗后移栽到泥炭土、珍珠岩、黄土（1：1：1,V/V/V）混合基质中,成活率达85%以上。     

从仿生学到神经科学

在中国科学院生物物理研究所,从仿生学到神经科学研究方向的确立,经历了几代人的艰辛努力.从1959年生物物理研究所三人理论组(仿生学研究室的前身)的成立,到2005年脑与认知科学国家重点实验室申报成功,走过了46年历程,本文拟对这段历史进行回顾和评述.