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Regulation Processes (regulation + process)
Kinds of Regulation Processes Selected AbstractsFunctional morphology and patterns of blood flow in the heart of Python regius,JOURNAL OF MORPHOLOGY, Issue 6 2009J. Matthias Starck Abstract Brightness-modulated ultrasonography, continuous-wave Doppler, and pulsed-wave Doppler-echocardiography were used to analyze the functional morphology of the undisturbed heart of ball pythons. In particular, the action of the muscular ridge and the atrio-ventricular valves are key features to understand how patterns of blood flow emerge from structures directing blood into the various chambers of the heart. A step-by-step image analysis of echocardiographs shows that during ventricular diastole, the atrio-ventricular valves block the interventricular canals so that blood from the right atrium first fills the cavum venosum, and blood from the left atrium fills the cavum arteriosum. During diastole, blood from the cavum venosum crosses the muscular ridge into the cavum pulmonale. During middle to late systole the muscular ridge closes, thus prohibiting further blood flow into the cavum pulmonale. At the same time, the atrio-ventricular valves open the interventricular canal and allow blood from the cavum arteriosum to flow into the cavum venosum. In the late phase of ventricular systole, all blood from the cavum pulmonale is pressed into the pulmonary trunk; all blood from the cavum venosum is pressed into both aortas. Quantitative measures of blood flow volume showed that resting snakes bypass the pulmonary circulation and shunt about twice the blood volume into the systemic circulation as into the pulmonary circulation. When digesting, the oxygen demand of snakes increased tremendously. This is associated with shunting more blood into the pulmonary circulation. The results of this study allow the presentation of a detailed functional model of the python heart. They are also the basis for a functional hypothesis of how shunting is achieved. Further, it was shown that shunting is an active regulation process in response to changing demands of the organism (here, oxygen demand). Finally, the results of this study support earlier reports about a dual pressure circulation in Python regius. J. Morphol., 2009. © 2008 Wiley-Liss, Inc. [source] Proteasome- and SCF-dependent degradation of yeast adenine deaminase upon transition from proliferation to quiescence requires a new F-box protein named Saf1pMOLECULAR MICROBIOLOGY, Issue 4 2006Stéphanie Escusa Summary In response to nutrient limitation, Saccharomyces cerevisiae cells enter into a non-proliferating state termed quiescence. This transition is associated with profound changes in gene expression patterns. The adenine deaminase encoding gene AAH1 is among the most precociously and tightly downregulated gene upon entry into quiescence. We show that AAH1 downregulation is not specifically due to glucose exhaustion but is a more general response to nutrient limitation. We also found that Aah1p level is tightly correlated to RAS activity indicating thus an important role for the protein kinase A pathway in this regulation process. We have isolated three deletion mutants, srb10, srb11 and saf1 (ybr280c) affecting AAH1 expression during post-diauxic growth and in early stationary phase. We show that the Srb10p cyclin-dependent kinase and its cyclin, Srb11p, regulate AAH1 expression at the transcriptional level. By contrast, Saf1p, a previously uncharacterized F-box protein, acts at a post-transcriptional level by promoting degradation of Aah1p. This post-transcriptional regulation is abolished by mutations affecting the proteasome or constant subunits of the SCF (Skp1,Cullin,F -box) complex. We propose that Saf1p targets Aah1p for proteasome-dependent degradation upon entry into quiescence. This work provides the first direct evidence for active degradation of proteins in quiescent yeast cells. [source] Libéralisation des Services publics de réseau et jeux croisés de la régulation: le cas de l'électricitéANNALS OF PUBLIC AND COOPERATIVE ECONOMICS, Issue 4 2001Frédéric Varone This article analyses the liberalization of public services with a special focus on the (re)regulation process that is induced. Firstly, a conceptual framework is developed in order to identify the constitutive elements of the public regulation related to market competition, public service obligations, operators and public property, as well as the tension between them. Secondly, a comparative study describes the liberalization and the regulatory design of the electricity sector in England, France, Germany, Norway and Switzerland. As a conclusion, we note the necessity to further analyse the introduction of market mechanisms into formerly monopolistic network industries and its effects. [source] Impacts of a law fostering training development: Lessons from Quebec's experienceCANADIAN PUBLIC ADMINISTRATION/ADMINISTRATION PUBLIQUE DU CANADA, Issue 3 2007Jean Chrest In 1995, the Quebec government adopted a unique law in North America in this regard: An Act to Foster the Development of Manpower Training. The "1% Wage Bill Law" was intended to improve the qualifications, skills and performance of workers through training. This article investigates three impacts of this law: the level of investment by firms; the distributional aspect of the law in terms of its capacity to ensure a more equitable investment in training for the different categories of workers in firms; and, finally, the structural aspect in terms of establishing partnerships. From a theoretical perspective, the Quebec experience illustrates that, between the liberal approach and the institutionalist approach (market versus institutions), it is possible to observe a compromise being made by social actors with respect to the regulation process, which at the same time respects the decisional space of firms. Another observation relates to the complementary aspect of institutional forms in labour-market regulation and to the fundamental role of unions in partnershipbuilding. Sommaire: Depuis les années 1980, de nombreuses etudes au Canada ont révélé un faible degré de participation des entreprises à la formation et ont ainsi soulevé la question du rôle de la politique gouvemementale. En 1995, le gouvemement du Québec a adoptéà cet égard une loi unique en son genre en Amérique du Nord: une Loi fauorisant le de'veloppement de la formation de la main-d,,uvre. La G loi du 1 % de la masse salariale "visait à améliorer les qualifications, les competences et la performance des travailleuses et travailleurs grâce 5 la formation. Le présent article examine trois impacts de cette loi: le niveau d'investissement des entreprises; l'aspect répartition de la loi en termes de sa capacitéà s' assurer que des investissements plus équitables soient consacrés à la formation pour différentes catégories de travailleuses et travailleurs dans les entreprises; et enfin, l'aspect structurel pour ce qui est de l'établissement de partenariats. D'un point de vue théorique, l'expérience du Québec illustre qu'entre l'approche libérale et l'approche institutionnelle (marché contre institutions), il est possible d'observer un compromis de la part des acteurs sociaux en ce qui concerne le processus de réglementation, qui respecte en même temps l'espace décisionnel des entreprises. Une autre observation porte sur l'aspect complémentaire des formes institutionnelles dans la réglementation du marché du travail et sur le rôle fondamental des syndicats dans l,établissement de partenariats. [source] Interactions of orexins/hypocretins with adrenocortical functionsACTA PHYSIOLOGICA, Issue 3 2010S. M. Kagerer Abstract The neuropeptides orexin A and B (hypocretin-1 and -2) are involved in numerous central regulation processes such as energy homeostasis, sleeping behaviour and addiction. The expression of orexins and orexin receptors in a variety of tissues outside the brain and the presence of orexin A in the circulation indicate the existence of an additional peripheral orexin system. Furthermore, it is well established that orexins exert an influence on the regulation of the hypothalamus,pituitary,adrenal axis, acting both on its central and peripheral branch. In rat and human adrenal cortices the expression of both orexin receptors has been verified with a predominance of OX2R. The local expression of orexin receptors was observed to be gender specific and to be modified by plasma glucose and insulin concentrations, nutritional status as well as gonadal steroids. Various studies consistently demonstrated orexin A to enhance glucocorticoid secretion of rat and human adrenal cortices, while orexin B was found to be either less potent or ineffective. On the contrary, the influence of orexins on adrenocortical aldosterone production and cell proliferation is still more controversial. Recent findings indicate that orexins stimulate adrenocortical steroidogenesis by augmenting transcription of selective steroidogenic enzymes and proteins such as steroidogenic acute regulatory protein. Both, Gq and Gs, signalling pathways with a downstream activation of MAP kinases appear to be involved in this regulation. [source] Improving Emotion Regulation and Sibling Relationship Quality: The More Fun With Sisters and Brothers Program,FAMILY RELATIONS, Issue 5 2008Denise E. Kennedy Abstract: We examined the role of emotion regulation (ER) in improving sibling relationship quality (SRQ) by evaluating the More Fun With Sisters and Brothers Program where 4- to 8-year-old siblings from 95 families were taught emotional and social competencies. Parents reported on SRQ and ER, and sibling interactions were observed in homes. SRQ and ER improved for program participants (n = 55) in comparison to those in a wait list condition (n = 40). Children participating in the program needed less parental direction to control negative emotions and refrain from directing negative actions toward others following the program. Higher levels of ER were linked with more positive SRQ at posttest. Results highlight the value of strengthening children's emotion regulation processes as a mechanism for promoting prosocial sibling relationships. [source] The structural comparison of the bacterial PepX and human DPP-IV reveals sites for the design of inhibitors of PepX activityFEBS JOURNAL, Issue 8 2005Pascal Rigolet X-prolyl dipeptidyl aminopeptidases (X-PDAP) are enzymes catalysing the release of dipeptides from the amino termini of polypeptides containing a proline or an alanine at the penultimate position. Involved in various mammalian regulation processes, as well as in chronic human diseases, they have been proposed to play a role in pathogenicity for Streptococci. We compared the structure of X-PDAP from Lactococcus lactis (PepX) with its human counterpart DPP-IV. Despite very different overall folds, the residues most implicated for X-PDAP activity are conserved in the same positions and orientations in both enzymes, thus defining a structural signature for the X-PDAP specificity that crosses the species frontiers of evolution. Starting from this observation, we tested some inhibitors of DPP-IV on PepX activity, for which no specific inhibitor is known. We thus found that PepX was highly sensitive to valine-pyrrolidide with a KI of 9.3 µm, close to that reported in DPP-IV inhibition. We finally used the structure of PepX from L. lactis as a template for computer-based homology modeling of PepX from the pathogenic Streptococcus gordonii. Docking simulations of valine-pyrrolidide into the active site of PepX led to the identification of key residues for a rational drug design against PepX from Streptococci. These results could have applications in human health giving new perspectives to the struggle against pathogens. [source] Functional dissection of an intrinsically disordered protein: Understanding the roles of different domains of Knr4 protein in protein,protein interactionsPROTEIN SCIENCE, Issue 7 2010Adilia Dagkessamanskaia Abstract Knr4, recently characterized as an intrinsically disordered Saccharomyces cerevisiae protein, participates in cell wall formation and cell cycle regulation. It is constituted of a functional central globular core flanked by a poorly structured N-terminal and large natively unfolded C-terminal domains. Up to now, about 30 different proteins have been reported to physically interact with Knr4. Here, we used an in vivo two-hybrid system approach and an in vitro surface plasmon resonance (BIAcore) technique to compare the interaction level of different Knr4 deletion variants with given protein partners. We demonstrate the indispensability of the N-terminal domain of Knr4 for the interactions. On the other hand, presence of the unstructured C-terminal domain has a negative effect on the interaction strength. In protein interactions networks, the most highly connected proteins or "hubs" are significantly enriched in unstructured regions, and among them the transient hub proteins contain the largest and most highly flexible regions. The results presented here of our analysis of Knr4 protein suggest that these large disordered regions are not always involved in promoting the protein,protein interactions of hub proteins, but in some cases, might rather inhibit them. We propose that this type of regions could prevent unspecific protein interactions, or ensure the correct timing of occurrence of transient interactions, which may be of crucial importance for different signaling and regulation processes. [source] Proteomic analysis of nuclear proteins from proliferative and differentiated human colonic intestinal epithelial cellsPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 1 2004Natacha Turck Abstract Self-renewing tissues such as the intestine contain progenitor proliferating cells which subsequently differentiate. Cell proliferation and differentiation involve gene regulation processes which take place in the nucleus. A human intestinal epithelial cell line model (Caco2/TC7) which reproduces these dynamic processes has been used to perform proteomic studies on nuclear proteins. Nuclei from Caco2/TC7 cells at proliferative and differentiated stages were purified by subcellular fractionation. After two-dimensional gel electrophoresis separation and ruthenium staining, 400 protein spots were detected by image analysis. Eighty-five spots corresponding to 60 different proteins were identified by matrix-assisted laser desorption/ionization mass spectrometry in nuclei from proliferative cells. Comparison of nuclear proteomes from proliferative or differentiated cells by differential display resulted in the identification of differentially expressed proteins such as nucleolin, hnRNP A2/B1 and hnRNP A1. By using Western blot analysis, we found that the expression and number of specific isoforms of these nuclear proteins decreased in differentiated cells. Immunocytochemistry experiments also showed that in proliferative cells nucleolin was distributed in nucleoli-like bodies. In contrast, hnRNPs A2/B1 and A1 were dispersed throughout the nucleus. This study of the nuclear proteome from intestinal epithelial cells represents the first step towards the establishment of a protein database which will be a valuable resource in future studies on the differential expression of nuclear proteins in response to physiological, pharmacological and pathological modulations. [source] Changes in emotion regulation and psychological adjustment following use of a group psychosocial support program for women recently diagnosed with breast cancerPSYCHO-ONCOLOGY, Issue 3 2007Linda D. Cameron Abstract This study assesses the efficacy of a group intervention in altering emotion regulation processes and promoting adjustment in women with breast cancer. Using a design with 10 alternating phases of availability of the intervention versus standard care, we assessed women participating in one of three conditions: a 12-week group intervention (N = 54); a decliner group who refused the intervention (N = 56), and a standard care group who were not offered the intervention (N = 44). The intervention included training in relaxation, guided imagery, meditation, emotional expression, and exercises promoting control beliefs and benefit-finding. Emotion regulation processes and adjustment were assessed at baseline (following diagnosis), 4 months (corresponding with the end of the intervention), 6 months, and 12 months. At 4 months, intervention participants (compared to decliners and standard care participants) reported greater increases in use of relaxation-oriented techniques, perceived control, emotional well-being, and coping efficacy, and, greater decreases in perceived risk of recurrence, cancer worry, and anxiety. Intervention participants also reported relatively greater decreases in emotional suppression from baseline to 12 months, suggesting that the intervention had a delayed impact on these tendencies. The findings suggest an emotion regulation intervention can beneficially influence emotional experiences and regulation over the first year following diagnosis. Copyright © 2006 John Wiley & Sons, Ltd. [source] Emotion regulation: Affective, cognitive, and social consequencesPSYCHOPHYSIOLOGY, Issue 3 2002James J. Gross One of life's great challenges is successfully regulating emotions. Do some emotion regulation strategies have more to recommend them than others? According to Gross's (1998, Review of General Psychology, 2, 271,299) process model of emotion regulation, strategies that act early in the emotion-generative process should have a different profile of consequences than strategies that act later on. This review focuses on two commonly used strategies for down-regulating emotion. The first, reappraisal, comes early in the emotion-generative process. It consists of changing the way a situation is construed so as to decrease its emotional impact. The second, suppression, comes later in the emotion-generative process. It consists of inhibiting the outward signs of inner feelings. Experimental and individual-difference studies find reappraisal is often more effective than suppression. Reappraisal decreases emotion experience and behavioral expression, and has no impact on memory. By contrast, suppression decreases behavioral expression, but fails to decrease emotion experience, and actually impairs memory. Suppression also increases physiological responding for suppressors and their social partners. This review concludes with a consideration of five important directions for future research on emotion regulation processes. [source] Research Review: A new perspective on attention-deficit/hyperactivity disorder: emotion dysregulation and trait modelsTHE JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY AND ALLIED DISCIPLINES, Issue 9 2009Michelle M. Martel Attention-deficit/hyperactivity disorder (ADHD) is a common example of developmental psychopathology that might be able to be better understood by taking an emotion regulation perspective. As discussed herein, emotion regulation is understood to consist of two component processes, emotion (e.g., positive and negative emotionality) and regulation (e.g., effortful and reactive forms of control), which interact with one another at the behavioral level. Review of work to date suggests that the heterogeneous behavioral category of ADHD may encompass two distinct kinds of inputs: inattentive ADHD symptoms may be primarily associated with breakdowns in the regulation side, whereas hyperactivity-impulsive ADHD symptoms may be associated with breakdowns in the emotionality side. It is argued that breakdowns in control may be a signature for ADHD specifically, while increased negative emotionality may serve as non-specific risk factors for disruptive behavior disorders, explaining their comorbidity. Increased understanding of the interrelations and interactions of component emotion regulation processes may elucidate developmental, sex, and neural mechanisms of ADHD and associated comorbid disruptive disorders. [source] Emotion and Emotion Regulation: A Map for Psychotherapy ResearchersCLINICAL PSYCHOLOGY: SCIENCE AND PRACTICE, Issue 4 2007Jonathan Rottenberg Never before has the pace of research on emotion and emotion regulation been as vigorous as it is today. This news is welcomed by researchers who study psychological therapies and who believe that emotion and emotion regulation processes are fundamental to normal and abnormal functioning. However, one unwelcome consequence of this otherwise happy state of affairs is that therapy researchers now face an array of bewildering decisions about what to measure and why. What is needed is a map that will help researchers make wise decisions in this domain. In this spirit, we locate Sloan and Kring's (2007) important review of available emotion and emotion regulation measures within the wider field of affective constructs and the broader problem space of psychotherapy research. Where appropriate, we illustrate our points with examples from our own work, and highlight the payoffs and challenges of integrating affective and clinical science. [source] |