The transcendental meditation technique, adrenocortical activity, and implications for stress.

The practice of the transcendental meditation technique in subjects eliciting this state regularly for 3--5 years is correlated with acute decline of adrenocortical activity not associated with sleep during the practice.     

Biological activity and pathological implications of misfolded proteins

The physiological metabolism of proteins guarantees that different cellular compartments contain the appropriate concentration of proteins to perform their biological functions and, after a variable period of wear and tear, mediates their natural catabolism. The equilibrium between protein synthesis and catabolism ensures an effective turnover, but hereditary or acquired abnormalities of protein structure can provoke a premature loss of biological function, an accelerated catabolism and diseases caused by the loss of an irreplaceable function. In certain proteins, abnormal structure and metabolism are associated with a strong tendency to self-aggregation into a polymeric fibrillar structure, and in these cases the disease is not principally caused by the loss of an irreplaceable function but by the action of this new biological entity. Amyloid fibrils are an apparently inert, insoluble, mainly extracellular protein polymer that kills the cell without tissue necrosis but by activation of the apoptotic mechanism. We analyzed the data reported so far on the structural and functional properties of four prototypic proteins with well-known biological functions (lysozyme, transthyretin, β2-microglobulin and apolipoprotein AI) that are able to create amyloid fibrils under certain conditions, with the perspective of evaluating whether the achievement of biological function favors or inhibits the process of fibril formation. Furthermore, studying the biological functions carried out by amyloid fibrils reveals new types of protein-protein interactions in the transmission of messages to cells and may provide new ideas for effective therapeutic strategies. Received 9 November 1998; received after revision 15 January 1999; accepted 15 January 1999     

Regulation of estrogen receptor beta activity and implications in health and disease

Together with the estrogen receptor (ER) alpha, estrogen receptor beta (ERβ) mediates many of the physiological effects of estrogens. As ERβ is crucially involved in a variety of important physiological processes, its activity should be tightly regulated. ERβ regulation is achieved by hormone binding as well as by posttranslational modifications of the receptor. Furthermore, ERβ expression levels are under circadian control and can be regulated by DNA methylation of the ERβ promoter region. There are also a number of factors that can interfere with ERβ activity, such as phytoestrogens, endocrine disruptive chemicals, and growth factors. In this article, we outline different mechanisms of ERβ regulation and how they are implicated in various diseases. We also discuss how these insights might help to specifically target ERβ in drug design.     

The structure and function of nuclear lamins: implications for disease

The nuclear lamins polymerize to form the nuclear lamina, a fibrous structure found on the inner face of the nuclear membrane. The lamins also appear to form structures within the nucleoplasm. These various lamin structures help to establish and maintain the shape and strength of the interphase nucleus, but recent work also suggests that the lamins have a role in nuclear processes such as DNA replication. Furthermore, mutations in the human lamin A/C gene have recently been linked to several diseases, including Emery-Dreifuss muscular dystrophy. This review discusses the nature of these mutations and the possible effects of lamin mutations on nuclear function.     

The cognition-knowledge distinction in Kant and Dilthey and the implications for psychology and self-understanding

Both Kant and Dilthey distinguish between cognition and knowledge, but they do so differently in accordance with their respective theoretical interests. Kant’s primary cognitive interest is in the natural sciences, and from this perspective the status of psychology is questioned because its phenomena are not mathematically measurable. Dilthey, by contrast, reconceives psychology as a human science.For Kant, knowledge is conceptual cognition that has attained certainty by being part of a rational system. Dilthey also links knowledge with certainty; however, he derives the latter from life-experience rather than from reason. Dilthey’s psychology begins with the self-certainty of lived experience and life-knowledge, but this turns out to fall short of cognitive understanding. In the final analysis, both Kant and Dilthey move beyond psychology to arrive at self-understanding. Because of his doubts about introspection, Kant replaces psychology with a pragmatic anthropology to provide a communal framework for self-understanding. Dilthey supplements psychology with other human sciences as part of a project of anthropological reflection.     

The relationship between high and low trait psychological stress,serum testosterone,and serum cortisol

Summary Psychological stress, as measured by the parameters of trait anxiety, hostility, and depression, was compared in the group of males age 30–55 with serum levels of testosterone. Those males who were classified as high psychological stress had significantly lower testosterone levels than did their low stress counterparts. However, comparison of their serum cortisol values revealed similar concentrations in both groups.     

Forecasting technique familiarity,satisfaction, usage,and application

A ten-year retrospective study of Mentzer and Cox (1984) was undertaken to answer the question 'Have sales forecasting practices changed over the past ten years?' A mail survey of 207 forecasting executives was employed to investigate this important question. Findings revealed both discrepancies and similarities between today's sales forecasting practices and those of ten years ago. One particular finding indicated greater reliance on and satisfaction with quantitative forecasting techniques today versus ten years ago. Another indicated that forecasting accuracy has not improved over the past ten years, even though the familiarity and usage of various sophisticated sales forecasting techniques have increased. Future research and managerial implications are discussed based on these and other findings.     

The problem of sea urchin egg fertilization and its implications for biological studies

Summary The analysis of sea urchin egg fertilization shows that several phenomena common to other biological systems are involved: cell recognition, cell fusion, exocytosis and initiation of mitotic activity. Both the role of calcium ions in cell fusion and exocytosis, and the function of the cell surface in the initiation of mitotic activity appear to have general applicability. The study of fertilization can contribute to the elucidation of these processes and, reciprocally, progress in this field can help to advance our understanding of the mechanisms of fertilization in sea urchins and other organisms.     

The impact of HIV-1 on neurogenesis: implications for HAND

HIV-1 infection, in addition to its destructive effects on the immune system, plays a role in the development of neurocognitive deficits. Indeed up to 50 % of long-term HIV infected patients suffer from HIV-associated neurocognitive disorders (HAND). These deficits have been well characterized and defined clinically according to a number of cognitive parameters. HAND is often accompanied by atrophy of the brain including inhibition of neurogenesis, especially in the hippocampus.  Many mechanisms have been proposed as contributing factors to HAND including induction of oxidative stress in the central nervous system (CNS), chronic microglial-mediated neuroinflammation, amyloid-beta (Aβ) deposition, hyperphosphorylated tau protein, and toxic effects of combination antiretroviral therapy (cART). In these review we focus solely on recent experimental evidence suggesting that disturbance by HIV-1 results in impairment of neurogenesis as one contributing factor to HAND. Impaired neurogenesis has been linked to cognitive deficits and other neurodegenerative disorders. This article will highlight recently identified pathological mechanisms which potentially contribute to the development of impaired neurogenesis by HIV-1 or HIV-1-associated proteins from both animal and human studies.     

Effect of conflict stress on adrenoreceptors and metabolic activity of the rat heart

Summary Exposure of rats to a conflict situation (electric shocks associated with water supply) increased the activities of oxidative enzymes and of heksokinase in the myocardium. The stress also led to subsensitivity of atrial -adrenoreceptors.     

The relationship between high and low trait psychological stress and serum indicators of stress

Summary Psychological stress as measured by the parameters of trait anxiety, hostility, and depression was compared in 2 different age groups (age 18–30 and 30–55) with serum indicators of stress. There was no significant difference between high and low psychological stress subjects in either age group with any of the serum indicators.     

The problem of sea urchin egg fertilization and its implications for biological studies.

The analysis of sea urchin egg fertilization shows that several phenomena common to other biological systems are involved: cell recognition, cell fusion, exocytosis and initiation of mitotic activity. Both the role of calcium ions in cell fusion and exocytosis and the function of the cell surface in the initiation of mitotic activity appear to have general applicability. The study of fertilization can contribute to the elucidation of these processes and, reciprocally, progress in this field can help to advance our understanding of the mechanisms of fertilization in sea urchins and other organisms.     

天宫一号整体壁板式密封舱结构技术

2011年9月,天宫一号目标飞行器发射升空,于2011年11月、2012年6月和2013年6月与3艘载人飞船完成3次交会对接,航天员两次进入实验舱生活和工作.实验舱是目前国内首个在轨工作2年以上的载人密封舱,该密封舱首次采用整体壁板式结构.本文分析了长寿命载人密封舱结构设计约束条件,通过不同结构形式的比较,提出了密封舱采用整体壁板结构,介绍了壁板结构设计准则和研究内容.该项设计技术的突破为我国未来大型长寿命载人航天器,尤其是载人空间站结构奠定了基础.