Evidence against Stable Protein S-Nitrosylation as a Widespread Mechanism of Post-translational Regulation

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Protein Phosphorylation as a Key Mechanism for the Regulation of BCL-3 Activity

Constitutive NF-?B activation, a hallmark of many human cancers, upregulates anti-apoptotic gene expression and therefore disrupts the balance between apoptosis and proliferation. In some lymphomas, this constitutive NF-?B activity is the result of point mutations or translocations of the genes coding for NF-?B inhibitors, namely I?B? or p100. The BCL-3 protein is another member of the I?B family and is overexpressed in a subset of human B-cell chronic lymphocytic leukemias because of a chromosomal translocation. This oncoprotein is phosphorylated by multiple kinases including GSK3 and this phosphorylation regulates BCL-3 function by modulating its oncogenic potential and by regulating the expression of a subset of its target genes. Therefore, deciphering the NF-?B/I?B protein phosphorylations is critical in order to better understand the molecular mechanisms of NF-?B-mediated oncogenesis.     

Bilateral Regulation of Ontogenetic Development in Humans

A hierarchical, multilevel, vertically organized system regulating all energy and information inputs is the basic regulating mechanism of the properties of ontogenetic development. However, this hierarchical regulatory system (with its cortico-reticular nucleus) is not the only mechanism of control and communication.     

Behavior as a social construction

Behavior analysis is examined from a social constructionist perspective. Constructionism is first defined and contrasted with a generic positivistic image of science. Behavior analysis, especially the matching law, is then viewed from both perspectives. The actual practice of behavior analysis (as opposed to the philosophy of radical behaviorism) more strongly resembles positivist than constructionist views. This alignment between behavior analysis and positivism emerges more sharply when positivist and constructionist perspectives are compared on the relation between science and music. Charles Rosen has identified how the classical style of musical composition and performance depended on 18th century keyboard technology, and a constructionist view sees the matching law as reflecting mid 20th century technology and culture in much the same way as it sees, say Mozart's 23rd piano concerto, as reflecting late 18th century culture. Behavior analysts, who often behave as though they see the matching law as an objective, impersonal, stable, hard, cold, incontrovertibly true fact, appear more inclined than constructionists to see a fundamental difference between the matching law and Mozart's 23rd piano concerto, to which they would attribute few if any of these characteristics. Possible implications are derived for tolerance in science.     

Prenatal Androgen Effects as a Proximate Mechanism Underpinning Variation in Social Behavior Among Female Nonhuman Primates

International Journal of Primatology - While the role of ecological factors in shaping primate social systems has been a central focus for decades, less attention has been given to phylogenetic...     

Bilateral testicular infarction and orchiectomy as a complication of polyarteritis nodosa

We report an unusual case of a 28-year-old male with constitutional symptoms and bilateral testicular pain. After diagnosis of cytomegalovirus (CMV) hepatitis, his constitutional symptoms and testicular pain worsened despite treatment for epididymoorchitis. Ultrasound was concerning for infarction. Exploration in the operating room revealed bilateral testicular infarction requiring bilateral orchiectomy with subsequent androgen hormone replacement. Pathologic diagnosis was polyarteritis nodosa (PAN). PAN is a rare systemic vasculitis that affects multiple organs. There are no previous reports of PAN-induced vasculitis leading to bilateral testicular infarction and bilateral orchiectomy.     

印记控制区(ICR)的调控机制

绝大多数印记基因成簇地分布在很大的染色体区域,在发育过程中起着十分重要的作用。印记基因等位位点专一性的抑制是由印记控制区(imprinting control region,ICR)所调控的,通常是等位位点一方的ICR发生甲基化。在配子形成过程中,非组蛋白和邻近的序列会影响这种差别甲基化。DNA的甲基化、组蛋白的修饰以及多梳状体蛋白对于印记的维持十分重要。不同印记区的印记调控的方式是不同的。在某些区域ICR组装成绝缘子,干扰启动子和增强子的相互作用,而在另一些区域中涉及到了非编码RNA,印记调控以一种与X染色体失活机制类似的方式进行。     

脂肪细胞分化作用及其分子调控机理

肥胖症是影响人类健康的严重问题之一。在过去的十年中,对脂肪细胞的生物功能和分化作用的分子机理的了解方面取得了突破性的进展。脂肪组织不仅是被动的能量贮存场所,同时还是能够分泌多种生物活性物质的器官。已发现多种能调节脂肪细胞分化的转录因子。看来Ｃ／ＥＢＰα和ＰＰＡＲγ很可能是调节这种分化过程的主控基因。     

油菜素甾醇信号转导的调控机制

油菜素甾醇是一类具有广泛调控功能的植物激素。本文对油菜素甾醇信号转导途径以及参与转导途径的调控的元件、转录因子等进行综述。     

Nightmares as a Coping Mechanism for Stress

The cause of nightmares remains unclear. However, previous research suggests that stress may play a key role and that nightmares may actually serve a beneficial function. Thus, the purpose of this study was to examine the overall relationship between these two variables and assess the hypothesis that nightmares serve as a coping mechanism for stress. To accomplish these goals, a group of 412 psychology students were separated into low, medium, and high nightmare frequency groups as well as low, medium, and high nightmare intensity groups. Comparisons were then conducted for daily stressors, life stressors, social support, and coping. Most notably, this study demonstrated a positive association between nightmares and coping with stress. The overall pattern seen in the analyses reflect the significant relationship between nightmares and stress, while the finding that nightmares were positively associated with coping bolsters the supposition that nightmares may help to alleviate stress.     

Hormonal Regulation of Female Reproductive Behavior in Fish

SYNOPSIS. Fundamentally different mechanisms regulate femalesexual behavior in the ovoviviparous guppy and the oviparousgoldfish. In the female guppy, ovarian estrogen evidently synchronizescycles of sexual receptivity with endogenous cycles of ovarianmaturation and also increases female attractivity at the timeof maximum receptivity by stimulating the release of a sexualpheromone. In the goldfish, it appears that prostaglandin, releasedfrom the ovary or oviduct in conjunction with ovulation andthe presence of ovulated eggs, acts on the brain to stimulatespawning behavior. In contrast to the situation in the guppy,steroid treatments alone (in the absence of ovulated eggs) failto stimulate spawning behavior in the goldfish. It isproposedthat endocrine mechanisms regulating female sexual behaviorin the teleosts and in other vertebrates are less related tophylogeny than to the mode of reproduction employed. In thegoldfish and several other externally fertilizing teleosts,where sexual behavior involves oviposition, female sexual behaviorapparently is synchronized with ovulation by mechanisms whichrespond to elevated plasma prostaglandin as an indicator ofthe presence of ovulated eggs. In internally fertilizing species(guppy, reptiles, birds, mammals), where sexual behavior andfertilizationare temporally dissociated, female sexual behavior is synchronizedwith ovulation by mechanisms which anticipate either an imminentspontaneous ovulation, or the potential for reflex ovulation,by responding to increases in plasma estrogen associated withfolliculardevelopment.     

Cultural Rules, Rituals, and Behavior Regulation

While it is generally agreed that culture and biology are both relevant to an understanding of human behavior, there is little consensus about the appropriate use of reductionist procedures. Disagreement abounds concerning the nature of the interaction and the relative contribution of distal and proximal mechanisms. An understanding of such issues may emerge only with long study of the interaction of variables at different conceptual levels of organization that intervene between the genes and culture. It is toward this larger end that the limited efforts of this paper are directed. Two cultural phenomena are considered: Murdoch's social laws of sexual choice, and aspects of human ritual behavior. Although these constitute a unique organization of cultural items, I attempt to show how they are influenced by underlying biopsychological processes. I specifically reject, however, the view that cultural phenomena are isomorphic with, or can be completely reduced to, such processes. Emergent novelty and multiple possibilities are always present at more inclusive levels of organization. I argue that the relationship between the different sets of system variables is based on homologous functions and not merely on analogies.
SEYMOUR PARKER is Professor, Department of Anthropology, University of Utah, Salt Lake City. UT 84112     

Oscillatory Behavior of Neutrophils under Opposing Chemoattractant Gradients Supports a Winner-Take-All Mechanism

Neutrophils constitute the largest class of white blood cells and are the first responders in the innate immune response. They are able to sense and migrate up concentration gradients of chemoattractants in search of primary sites of infection and inflammation through a process known as chemotaxis. These chemoattractants include formylated peptides and various chemokines. While much is known about chemotaxis to individual chemoattractants, far less is known about chemotaxis towards many. Previous studies have shown that in opposing gradients of intermediate chemoattractants (interleukin-8 and leukotriene B₄), neutrophils preferentially migrate toward the more distant source. In this work, we investigated neutrophil chemotaxis in opposing gradients of chemoattractants using a microfluidic platform. We found that primary neutrophils exhibit oscillatory motion in opposing gradients of intermediate chemoattractants. To understand this behavior, we constructed a mathematical model of neutrophil chemotaxis. Our results suggest that sensory adaptation alone cannot explain the observed oscillatory motion. Rather, our model suggests that neutrophils employ a winner-take-all mechanism that enables them to transiently lock onto sensed targets and continuously switch between the intermediate attractant sources as they are encountered. These findings uncover a previously unseen behavior of neutrophils in opposing gradients of chemoattractants that will further aid in our understanding of neutrophil chemotaxis and the innate immune response. In addition, we propose a winner-take-all mechanism allows the cells to avoid stagnation near local chemical maxima when migrating through a network of chemoattractant sources.     

Regulation of autophagy as a therapeutic option in glioblastoma

Apoptosis - Around three out of one hundred thousand people are diagnosed with glioblastoma multiforme, simply called glioblastoma, which is the most common primary brain tumor in adults. With a...     

miR-126调控前列腺癌机制研究

miR-126通过靶向作用于表皮生长因子域7（EGFL7）、同源框A9（HOXA9）、胰岛素受体底物-1（11LS-1）、p85-B基因等,在转录后水平调控靶基因表达,在肿瘤形成中起重要作用。前列腺癌细胞中高表达miR,126,能明显下调VEGF—A、EGLF7、HOXA9、VCAM—1等与肿瘤生长、转移密切相关的蛋白分子。miR-126作为抑癌因子,在多种肿瘤中均下调。其抑癌作用及机制在肺癌、白血病、乳腺癌、宫颈癌等中均已得到证实。本课题拟对miR-126调控前列腺癌机制做一综述。     

GABAB受体活性调控机制的研究进展

γ-氨基丁酸B型受体(GABAB receptor,GABABR)是由GABAB1(GB1)和GABAB2(GB2)亚基组成的异源二聚体,在中枢神经系统中介导持久而缓慢的神经抑制活动。GABAB受体活性受多种因素的调控,如受体的胞内运输、受体的内吞和再循环、受体与胞内蛋白相互作用等,在神经元维持突触可塑性、产生快速神经抑制信号等方面起着非常重要的作用,其活性失调则导致自发性癫痫、痉挛药物成瘾、精神分裂症等多种严重疾病。