茶及其多酚类化合物调节肥胖及并存症的研究进展

肥胖是备受全球关注的健康问题,主要表现在机体营养代谢失衡和脂肪积累。多项研究表明茶及其多酚类化合物具有降脂减肥、改善代谢、保护肝脏、降血压、降血糖等多种生理功能。本综述总结十年来有关茶及其多酚类化合物调节肥胖及并存症的研究,归纳出调节机理,主要包括调节食欲、减少能量摄入、促进脂质代谢和产热、抑制脂质生成和积累、调节肠道微生物、介导炎症及免疫反应。本综述在分析前人研究成果的基础上,为茶叶功能成分研究提供了新的研究思路和方向,有利于茶产品开发及应用推广。     

神经调节蛋白（neuromodulin）

神经调节蛋白是一种神经组织特异性的钙调素结合蛋白,与钙调素结合有反Ｃａ＾２＋依赖性。它与突触的可靠性、神经生长和再生有关。本简述其分离纯化、结构与功能以及ｃＤＮＡ克隆与表达等方面的研究现状。     

神经调节中的新概念：神经递质与调质

一、神经调节物——递质和调质 (一)神经化学传递——历史的回顾自20年代初,在Otto Loewi应用蛙心灌流,为神经的化学传递奠定基础以后的半个世纪里,大量的研究工作揭示了乙酰胆碱(ACh)和去甲肾上腺素(NE)在外周神经传递中的作用。首先是运动神经对横纹肌的支配,由于是神经末梢同肌纤维之间的点对点联系,其作用既迅速又精确,是由在神经肌接头处释放的ACh,在以毫秒计的时间内跨越突触间隙,作用于突触后受体,引起离子通道的启闭而实现的。其次是交感神经末梢释放NE,副交感释放ACh对平滑肌和腺体分泌的支配。由于缺乏点对点的直接联系,其作用较慢而持久。如此,ACh和NE在很长一段时间里基本概括了一切已     

"神经调节"备考复习随想

以“神经调节”单元的备考复习为例,探讨高三生物学的系统复习阶段,教师应如何确定单元复习目标,重组单元课题内容和设计单元复习方案,从而将培养学生科学素养的理念落到实处。     

肠道菌群在肥胖发病中的作用

近十年来,肠道菌群在人类许多疾病发病机制中的潜在作用引起了人们的广泛关注。已被证实肠道菌群与肥胖和肥胖相关的代谢性疾病的发生发展密切相关。与肥胖相关的肠道微生物可调控宿主的能量代谢、胰岛素抵抗和脂肪组织堆积,这些在肥胖发生中都起着至关重要的作用。本综述重点介绍了代谢紊乱中肠道菌群组成的变化以及肠道菌群在肥胖发病机制中的作用,包括能量代谢、中枢食欲、免疫系统和宿主昼夜节律。在不久的将来,该领域的研究将为治疗肥胖及其并发症开辟新的途径。     

“神经调节与体液调节的关系”的教学设计

“神经调节与体液调节的关系”一节内容,人教版和苏教版教材都有安排,但侧重点有所不同。这需要教师从课程标准的角度去分析教材的内涵,从新的层面去发掘知识的内在联系。     

“神经调节”的简笔画复习设计

通过"简笔画"分析法,充分借助形象思维,最大限度地挖掘学生的思维潜力,从而使学生的理解能力、获取信息能力、综合应用能力、探究能力等各方面能力得以提高。通过借图读表,学生掌握神经调节的最基本结构——反射弧的结构特点、功能;通过过程图,学生掌握并理解兴奋在神经纤维上的传导;通过对突触的简笔画分析,学生掌握兴奋在神经元之间的传递特点;再借助相应高考题针对性的评析及训练,学生不仅掌握了知识,获得了能力,而且在潜移默化中养成了借助适当的方法解决生物学问题的良好习惯。     

神经反馈调节失衡与帕金森病(Parkinson's desease)

机体的各种组织、器官和系统能维持正常的生理功能,离不开各种形式的反馈调节,这些调节包括神经调节,体液调节和局部的自身调节。机体生理活动的调节在分子、细胞和系统的各种水平都存在,而且每种反馈调节都必须得到精确控制,否则将会引起各种疾病。帕金森病的产生就是大脑有关脑区兴奋和抑制的反馈调节失衡造成的,它为我们理解生命活动过程中的反馈调节机制提供了一个极为典型的有重要价值的模型。[第一段]     

神经调节肽U受体的研究进展

神经调节肽U受体(neuromedim U receptor,NMUR)包括两个亚型,原为G蛋白偶联孤儿型受体FM3和FM4,最近证实其内源性配基为神经调节肽U（NMU）。大量的生物学研究结果表明,NMUR与食欲调节、能量代谢、应激反应及疼痛感受等生理功能密切相关,有可能成为治疗多种代谢性和心血管疾病的药物作用新靶点,为近年业的研究热点,该概述了NMUR的基因定位,组织分布、生理功能和配体结合等方面的研究进展。     

Mouse models for the central melanocortin system

Obesity is characterized by an excess storage of body fat and promotes the risk for complex disease traits such as diabetes mellitus and cardiovascular diseases. The obesity prevalence in Europe is rising and meanwhile ranges from 10 to 20% in men and 15–25% in women. Body fat accumulation occurs in states of positive energy balance and is favored by interactions among environmental, psychosocial and genetic factors. Energy balance is regulated by a complex neuronal network of anorexigenic and orexigenic neurons which integrates peripheral and central hormonal and neuronal signals relaying information on the metabolic status of organs and tissues in the body. A key component of this network is the central melanocortin pathway in the hypothalamus that elicits metabolic and behavioral adaptations for the maintenance of energy homeostasis. Genetic defects in this system cause obesity in mice and humans. In this review we emphasize mouse models with spontaneous natural mutations as well as targeted mutations that contributed to our understanding of the central melanocortin system function in the control of energy balance.     

朊病毒对中枢神经系统的影响及其作用机制

本文着重叙述了以几个问题：（１）朊病毒能否从牛转移感染到人;（２）朊病毒的感感染途径是怎样的;（３）朊病毒感染有何条件;（４）正常的朊病毒蛋白在神经元和胶质细胞表面表达有何重要功能;（５）朊病毒蛋白功能的结构基因;（６）朊病毒的可能作用机制。最后,分析了朊病毒影响中枢神经系统的两条可能途径,即破坏正常朊病毒蛋白的功能和与小神经胶质细胞共同作用提高神经元对自由基的敏感性及增加氧化自由基的含量。     

Ghrelin-mediated appetite regulation in the central nervous system

The gut hormone and neuropeptide ghrelin was initially identified in the periphery as a compound released in the bloodstream in response to a negative energetic status. In the central nervous system (CNS), ghrelin mainly acts on the hypothalamus and the limbic system, with its best-known biological role being the regulation of appetitive functions. Recent research has shown that ghrelin is not an indispensable factor in the regulation of food intake. However, it plays a key role in the metabolic changes of lipids, mainly those involving hypothalamic NOS, AMPK, CaMKK2, CPT1 and UCP2 proteins. Ghrelin participates in the regulation of memory processes and the feeling of pleasure resulting from eating, both of which are metabolism-dependent and may be essential for the successful achievement of adaptive appetitive behavior. Ghrelin exerts its biological effect through a complicated network of neuroendocrine links, including the melanocortin and endocannabinoid systems. The activity of ghrelin is connected with circadian and annual fluctuations, which depend on seasons and food availability.     

Tyrosine hydroxylase regulation in the central nervous system

Tyrosine hydroxylase is considered to be the rate-limiting enzyme in the synthesis of catecholamines in both the central and peripheral nervous system. Increased or decreased neuronal activity, stress, lesions, drug effects, endocrinological manipulations and experimental models of hypertension are associated with alterations in tyrosine hydroxylase activity in the central nervous system. In many of these instances, the changes in the activity of tyrosine hydroxylase in the central nervous system that occur are localized to discrete catecholaminergic pathways and nuclei in the brain. The purpose of this review is to summarize and assess this information and to provide insight into the function of catecholamine systems in the brain and their interactions with other putative neurotransmitter systems.     

Developmental regulation of the carbohydrate composition of glycoproteins associated with central nervous system myelin

Abstract: Glycoproteins from central nervous system myelin were evaluated for developmental alterations in their carbohydrate composition by autoradiographic analysis of radioiodinated lectin binding after separation by high-resolution sodium dodecyl sulfate-pore gradient slab gel electrophoresis (SDS-PGE). Sixteen lectin-binding components were assessed in highly purified myelin preparations from 15-day, 18-day, and adult rat brains, using the lectins Triticum vulgaris (wheat germ agglutinin) and Ulex europeus (gorse agglutinin I). Developmental changes in lectin binding for individual glycoproteins were evaluated semiquantitatively by comparing densitometric scans of the auto radiographs. Both increases and decreases in lectin binding for individual components were observed as a consequence of development, as well as the appearance and disappearance of lectin binding to three low-molecular-weight components. No changes in electrophoretic mobility and hence glycoprotein molecular weight were observed in any components when using these lectins. These developmental changes in lectin binding suggest that increases in glycoprotein (receptor) density occur, as well as an elaboration of oligosaccharide branching for individual glycoproteins. In addition, the appearance of a new glycoprotein in the adult myelin membrane could imply a new functional role not present in the immature membrane. These observations suggest that dynamic alterations of myelin-associated glycoproteins occur during development. Such developmental regulation of membrane glycoproteins increases the significance of their potential role in myelination and myelin maintenance.     

Pax gene expression in the developing central nervous system of Ciona intestinalis

We compare the expression patterns in Ciona intestinalis of three members of the Pax gene family, CiPax3/7, CiPax6 and Cipax2/5/8. All three genes are expressed in restricted patterns in the developing central nervous system. At the tailbud stage, CiPax3/7 is present in three patches in the brain and along the posterior neural tube, CiPax6 throughout the anterior brain and along the posterior neural tube and CiPax2/5/8 in a restricted region of the posterior brain. Double in situ hybridisations were used to identify areas of overlap between the expression of different genes. This showed that CiPax3/7 overlaps with the boundaries of CiPax6 expression in the anterior brain, and with CiPax2/5/8 in the posterior brain. The overlap between CiPax3/7 and CiPax2/5/8 is unlike that described in the ascidian Halocynthia rorezti.     

The relationship between excitotoxicity and oxidative stress in the central nervous system

Excitotoxicity and oxidative stress are two phenomena that have been repeatedly described as being implicated in a wide range of disorders of the nervous system. Such disorders include several common idiopathic neurological diseases, traumatic brain injury, and the consequences of exposure to certain neurotoxic agents. While there is evidence that metabolic derangements can laed to these adverse processes, and that these processes may synergize in their damaging effects, the degree of interdependence, and the causal relation between them is not clear. The intent of this review is to delineate potential mechanisms which may unit hyperexcitation to the excessive generation of reactive oxygen species. The degree of linkage between these events appears rather strong. It is likely that excitoxicity frequency leads to a pro-oxidant condition but that high rates of generation of reactive oxygen species are not invariably accompanied by a hyperexcited neuronal state Both excitoxic and ‘oxidotoxic’ states result from the failure of normal compensatory anti excitatory and antioxidant mechanisms to maintain cellular homeostatis.     

The fine structure of neuroglia in the central nervous system of nereid polychaetes

Summary The principal supportive elements of the nereid central nervous system are non-neuronal cells that are referred to as supportive glia. Supportive glial cells form a conspicuous cortex in the nerve cord. The inner region of this cortex consists of closely packed processes and cell bodies of fibrous supportive glial cells that are arranged in concentric layers around the perimeter of the neuropile. The fibrous appearance of the glial cells results from dense bundles of cytoplasmic filaments. Many fibrous glial processes penetrate the neuropile and ramify among the neuronal elements. Larger, irregularly shaped cells are the chief supportive glial elements of the peripheral region of the cortex where they line the stromal sheath (neural lamella) and invest the neuronal perikarya with extensive concentric systems of lamellate processes. These glial cells usually possess a relatively undifferentiated cytoplasm with scattered glycogen granules, but occasionally have a well developed Golgi apparatus, endoplasmic reticulum and densely packed particulate glycogen. The supportive glia exhibits numerous desmosomes as well as 5-layered (tight) and 7-layered (gap) junctions. Interspersed among the supportive glial cells are non-neuronal cells referred to as granulocytes. These cells have abundant large, granular inclusions, electron lucent vesicles, plasmalemmal infoldings and microtubules. The granulocytes may be derived from undifferentiated glial cells or may represent coelomocytes that have invaded the nervous tissue.Supported by USPHS Grants No. NIH 5P01 NS-07512, NIH 2T01 GM-00102, and NB-00840.The author acknowledges the excellent technical assistance of Sarah Wurzelmann and Stanley Brown, and thanks Dr. Berta Scharrer for many stimulating discussions.