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Kinds of Function Terms modified by Function Selected AbstractsIQ IN THE PRODUCTION FUNCTION: EVIDENCE FROM IMMIGRANT EARNINGSECONOMIC INQUIRY, Issue 3 2010GARETT JONES We show that a country's average IQ score is a useful predictor of the wages that immigrants from that country earn in the United States, whether or not one adjusts for immigrant education. Just as in numerous microeconomic studies, 1 IQ point predicts 1% higher wages, suggesting that IQ tests capture an important difference in cross-country worker productivity. In a cross-country development accounting exercise, about one-sixth of the global inequality in log income can be explained by the effect of large, persistent differences in national average IQ on the private marginal product of labor. This suggests that cognitive skills matter more for groups than for individuals. (JEL J24, J61, O47) [source] SEXUAL SELECTION AND IMMUNE FUNCTION IN DROSOPHILA MELANOGASTEREVOLUTION, Issue 2 2008Kurt A. McKean The evolution of immune function depends not only on variation in genes contributing directly to the immune response, but also on genetic variation in other traits indirectly affecting immunocompetence. In particular, sexual selection is predicted to trade-off with immunocompetence because the extra investment of resources needed to increase sexual competitiveness reduces investment in immune function. Additional possible immunological consequences of intensifying sexual selection include an exaggeration of immunological sexual dimorphism, and the reduction of condition-dependent immunological costs due to selection of ,good genes' (the immunocompetence handicap hypothesis, ICHH). We tested for these evolutionary possibilities by increasing sexual selection in laboratory populations of Drosophila melanogaster for 58 generations by reestablishing a male-biased sex ratio at the start of each generation. Sexually selected flies were larger, took longer to develop, and the males were more sexually competitive than males from control (equal sex ratio) lines. We found support for the trade-off hypothesis: sexually selected males were found to have reduced immune function compared to control males. However, we found no evidence that sexual selection promoted immunological sexual dimorphism because females showed a similar reduction in immune function. We found no evidence of evolutionary changes in the condition-dependent expression of immunocompetence contrary to the expectations of the ICHH. Lastly, we compared males from the unselected base population that were either successful (IS) or unsuccessful (IU) in a competitive mating experiment. IS males showed reduced immune function relative to IU males, suggesting that patterns of phenotypic correlation largely mirror patterns of genetic correlation revealed by the selection experiment. Our results suggest increased disease susceptibility could be an important cost limiting increases in sexual competitiveness in populations experiencing intense sexual selection. Such costs may be particularly important given the high intersex correlation, because this represents an apparent genetic conflict, preventing males from reaching their sexually selected optimum. [source] EXPERIMENTAL ANALYSIS OF THE DEFORMING MODE OF A SURFACE IN FUNCTION OF ITS ROUGHNESSEXPERIMENTAL TECHNIQUES, Issue 2 2000M. Dursapt First page of article [source] THE FUNCTION OF THE OTHER IN RECENT GERMAN MISSION CALLSINTERNATIONAL REVIEW OF MISSION, Issue 362 2002Arnd Bönker First page of article [source] A CHINESE HERBAL MEDICINE, CHOTO-SAN, IMPROVES COGNITIVE FUNCTION AND ACTIVITIES OF DAILY LIVING OF PATIENTS WITH DEMENTIA: A DOUBLE-BLIND, RANDOMIZED, PLACEBO-CONTROLLED STUDYJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 12 2005Tatsuya Suzuki MD No abstract is available for this article. [source] COMPLEX METHOD FOR NONLINEAR CONSTRAINED MULTI-CRITERIA (MULTI-OBJECTIVE FUNCTION) OPTIMIZATION of THERMAL PROCESSINGJOURNAL OF FOOD PROCESS ENGINEERING, Issue 4 2003FERRUH ERDO ABSTRACT The goal in a multi-objective function optimization problem is to optimize the several objective functions simultaneously. the complex method is a powerful algorithm to find the optimum of a general nonlinear function within a constrained region. the objective of this study was to apply the complex method to two different shapes (a sphere and a finite cylinder) subjected to the same thermal processing boundary conditions to find a variable process temperature profile (decision variable) to maximize the volume-average retention of thiamine. A process temperature range of 5 to 150C was used as an explicit constraint. Implicit constraints were center temperature and accumulated center lethality of the sphere and the finite cylinder. the objective functions for both shapes were combined into a single one using a weighting method. Then, the previously developed complex algorithm was applied using Lexicographic Ordering to order the objective functions with respect to their significance. the results were reported as optimum variable process temperature profiles using the given geometries and objective functions. the thiamine retentions were also compared with a constant process temperature process, and 3.0% increase was obtained in the combined objective function. the results showed that the complex method can be successfully used to predict the optimum variable process temperature profiles in multi-criteria thermal processing problems. [source] DOES THE CYTOSKELETON OF INTESTINAL EPITHHELIAL CELLS FUNCTION AS A CELLULAR ALARM TO IDENTIFY THE E. COLI INFECTIONJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 2001Zhe Li Intestinal epithelial cells play an important role in regulating host immunity in response to intestinal infection. Pathogenic bacteria (EPEC and EHEC) cause profound cytoskeletal rearrangement in intestinal epithelial cells during attachment or invasion. Rearrangement of cytoskeletal proteins could be a signal to up-regulate host defence response. Aims, To determine the role of actin cytoskeleton and microtubles in IL-8 mRNA response to E. coli infection. Methods, T84 cell monolayers in 6-well plates were infected with HB101, EPEC and EHEC (105 CFU/well) and compared with uninfected control at 3, 6 and 12 h post infection. Control and infected monolayers were treated with nocodazole (Noc, microtubule disrupter, 30 mm), taxol (Tax, microtubule stabiliser, 10 mm), cytochalasin D (CytoD, actin depolymeriser, 100 nm) and Jasplakinolide (Jasp, actin polymeriser, stabilise actin filaments, 1 mm) and studied 6 h post infection. IL-8 gene expression was measured by semiquantitative RT,PCR in control and uninfected monolayers with and without drug treatment and IL8 protein secretion by ELISA. The morphology of F-actin and ,-tubulin was examined by FITC-phaloidin staining (FAS), immunohistochemistry and confocal microscopy. Results, IL-8 mRNA and IL-8 were increased by infection with all bacterial strains at 3 and 6 h but both IL-8 mRNA and IL-8 in EHEC and EPEC infection were decreased compared with control and HB101 at 12 h. Disruption of microfilaments by Noc increased IL-8 (2.7 fold) while preservation of microfilaments by Tax inhibited IL8 response (0.5 fold) to HB101 infection only. CytoD decreased (0.1,0.5 fold) IL8 expression at all time points in all infections while stabilising actin by Jasp markedly increased the IL8 response (2,6 fold) in control, HB101, EHEC and EPEC at 3 and 6 h. CytoD inhibited Noc-induced IL8 gene expression. Confocal microscopy demonstrated that CytoD and Noc caused major morphological damage to the actin and ,-tubulin by 6 h. Similar changes were also observed in EPEC and EHEC infection at 12 h but not HB101. Jasp preserved actin stress filaments in both EPEC and EHEC. Conclusions, Disruption of microtubules and exogenous rearrangement of actin by pathogenic organism may be primary stimuli to up-regulate proinflammatory cytokine gene expression. Preservation of actin filaments is required for this response and may be necessary for signal transduction to the nucleus. [source] PHOTOSYNTHETIC FUNCTION IN DUNALIELLA TERTIOLECTA (CHLOROPHYTA) DURING A NITROGEN STARVATION AND RECOVERY CYCLEJOURNAL OF PHYCOLOGY, Issue 5 2003Erica B. Young Phytoplankton can be exposed to periods of N starvation with episodic N resupply. N starvation in Dunaliella tertiolecta (Butcher) measured over 4 days was characterized by slow reduction in cell chl and protein content and chl/carotenoid ratio and a decline in photosynthetic capacity and maximum quantum yield of photosynthesis (Fv/Fm). In the early stages of N starvation, cell division was maintained despite reduction in cellular chl. Chl content was more sensitive than carotenoids to N deprivation, and cellular chl a was maintained preferentially over chl b under N starvation. NO3, resupply stimulated rapid and complete recovery of Fv/Fm (from 0.4 to 0.7) within 24 h and commencement of cell division after 10 h, although N-replete levels of cell chl and protein were not reestablished within 24 h. Recovery of Fv/Fm was correlated with increases in cell chl and protein and was more related to increases in Fm than to changes in F0. Recovery of Fv/Fm was biphasic with a second phase of recovery commencing 4,6 h after resupply of NO3,. Uptake of NO3, from the external medium and the recovery of Fv/Fm, cell chl, and protein were inhibited when either cytosolic or chloroplastic protein synthesis was inhibited by cycloheximide or lincomycin, respectively; a time lag observed before maximum NO3, uptake was consistent with synthesis of NO3, transporters and assimilation enzymes. When both chloroplastic and cytosolic translation was inhibited, Fv/Fm declined dramatically. Dunaliella tertiolecta demonstrated a capacity to rapidly reestablish photosynthetic function and initiate cell division after N resupply, an important strategy in competing for limiting inorganic N resources. [source] CHARACTERIZATION OF AGGLOMERATION PROCESS AS A FUNCTION OF MOISTURE CONTENT USING A MODEL FOOD POWDERJOURNAL OF TEXTURE STUDIES, Issue 1 2006S. MUKHERJEE ABSTRACT A model food-powder system using rice flour of different moisture contents (11 to 22%) was used to study rheological behavior by employing a powder rheometer to obtain maximum force, energy for compression and decompression. The latter parameters were sensitive at moisture contents of ,18%. The compacted mass, obtained using a rotary punch-tableting machine, was subjected to compression testing to determine the maximum force and firmness of the compressed tablets. These two parameters increased markedly above the 17% moisture content. A significant (P , 0.01) relationship between energy for compression for powder and firmness of compacted mass indicated that an adequate integrity of the product could be achieved when a powder requires high energy for compression but low energy for decompression. A modified version of the Hausner ratio, often used to characterize the extent of compactness, was proposed that included a correction factor for loss of moisture during compaction. [source] QUANTITATIVE SENSORY TESTING AND SWEAT FUNCTION IN FRIEDREICH'S ATAXIA.JOURNAL OF THE PERIPHERAL NERVOUS SYSTEM, Issue 1 2000CORRELATION WITH CUTANEOUS INNERVATION To evaluate small fiber function in Friedreich's Ataxia (FA), we performed in 7 patients pin-prick, thermal thresholds, and sweat test. All tests were performed in four different sites: hand dorsum, anterior thigh, lateral distal leg, and foot dorsum. The same subjects underwent 3 mm punch skin biopsy from fingertip, anterior thigh, and lateral distal leg. We used a thin needle mounted on a calibrated nylon wire for the pin-prick test, and a Medoc 2001 TSA system for thermal threshold assessment. Sweat test was performed using a silicon mold after stimulation with pilocarpine by iontophoresis. Skin specimens, cut into 100-,m-thick sections, were double-stained using primary antibodies specific for collagen and nervous fibers and secondary antibodies labeled with Cy3 and Cy5 fluorophores. Tridimensional digitized images were obtained from z-series of 2-,m-thick optical sections acquired with a confocal microscope. We found in all patients in the more distal sites definite signs of functional impairment of the small fibers. These data correlated with the skin innervation morphological findings that showed, in the same sites, a sensible loss of small fibers regarding both the epidermal free endings and the subepidermal neural plexus. Less severe morphological abnormalities were found in the proximal sites. The large fiber neuropathy in FA is well documented. Our data show a length-dependent involvement of small fibers in the pathological process. [source] I. THE DEVELOPMENT OF EXECUTIVE FUNCTIONMONOGRAPHS OF THE SOCIETY FOR RESEARCH IN CHILD DEVELOPMENT, Issue 3 2003Article first published online: 8 DEC 200 First page of article [source] II. STUDY 1: MEMORY AND EXECUTIVE FUNCTIONMONOGRAPHS OF THE SOCIETY FOR RESEARCH IN CHILD DEVELOPMENT, Issue 3 2003Article first published online: 8 DEC 200 First page of article [source] III. STUDY 2: RULE COMPLEXITY AND STIMULUS CHARACTERISTICS IN EXECUTIVE FUNCTIONMONOGRAPHS OF THE SOCIETY FOR RESEARCH IN CHILD DEVELOPMENT, Issue 3 2003Article first published online: 8 DEC 200 First page of article [source] ASSESSMENT OF PLATELET FUNCTION IN HAEMODIALYSIS PATIENTSNEPHROLOGY, Issue 1 2002Duy Nguyen [source] DO PLASMA NON-ESTERIFIED FATTY ACIDS AND INSULIN RESISTANCE CONTRIBUTE TO IMPAIRED ENDOTHELIAL FUNCTION IN NEPHROTIC SYNDROME?NEPHROLOGY, Issue 1 2002G. Dogra [source] ENDOTHELIAL FUNCTION OF CONDUIT AND RESISTANCE ARTERIES IN NEPHROTIC RANGE PROTEINURIANEPHROLOGY, Issue 3 2000G. Dogra OBJECTIVE: To test the hypothesis that endothelial dysfunction occurs in nephrotic range proteinuria primarily as a consequence of dyslipidaemia. METHODS: Brachial artery and forearm microcirculatory endothelial function was compared among patients with nephrotic range proteinuria (NRP, n = 14 ), primary hyperlipidaemia (HL, n = 15) and normal controls (NC, n = 16). Endothelial function was studied by measuring post-ischaemic flow-mediated dilatation (FMD) of the brachial artery using high resolution ultrasonography. Endothelium-independent, glyceryl trinitrate (GTN) mediated brachial artery vasodilatation was also measured. Basal and post-ischaemic blood flow of the forearm microcirculation was measured using venous-occlusion strain gauge plethysmography. RESULTS: Serum creatinine was similar among groups. The proteinuric group had a mean albumin of 27.6g/L(1.8) and 24-hour urinary protein excretion of 6.3g(1.3). Plasma lipids and lipoproteins were not statistically different between the NRP and HL groups. Brachial artery FMD was significantly lower in the NRP and HL groups compared with the controls (NRP 4.7%(1.3)*, HL 4.9%(0.7)* and NC 8.3%(0.6), *p = 0.012 vs. NC); GTN mediated dilatation and basal and post-ischaemic forearm blood flow were not statistically different among the three groups. CONCLUSION: Patients with nephrotic range proteinuria have endothelial dysfunction of conduit arteries in the peripheral circulation, similar to that observed in patients with primary hyperlipidaemia. This suggests dyslipoproteinaemia is the principal cause of endothelial dysfunction of conduit arteries in nephrotic range proteinuria. Confirmation of this should be sought with an intervention trial of lipid-regulating therapy. [source] LIPID-LOWERING IMPROVES ENDOTHELIAL FUNCTION IN NEPHROTIC RANGE PROTEINURIANEPHROLOGY, Issue 3 2000G. Dogra OBJECTIVE: To determine whether lipid-modifying therapy with atorvastatin improves impaired endothelial function in patients with nephrotic range proteinuria (NRP). METHODS: A sequential, open-label study of the effects of atorvastatin on dyslipidaemia and endothelial dysfunction in 9 patients with NRP. Endothelial function was assessed at baseline, after 12 weeks of atorvastatin treatment and after an 8 week wash-out period. Brachial artery endothelial function was studied by measuring post-ischaemic flow-mediated dilatation (FMD) using ultrasonography. Endothelium- independent, glyceryl trinitrate (GTN) mediated vasodilatation was also measured. RESULTS: At baseline, median serum albumin was 31g/L (range 20-40) and 24 hour protein excretion was 4.7g (1.0-16.23). There was no significant change in serum creatinine and 24 hour protein excretion during the study. Total cholesterol (TC) and triglycerides (TG) were significantly lower following treatment with atorvastatin 20mg (20-40): TC 8.1mmol/L (5.9-14.9) vs. 5.2 (4.0-8.6), TG 2.9mmol/L (1.3-15.0) vs. 1.6 (1.0-3.5), both p < 0.05. Brachial artery FMD improved significantly following atorvastatin treatment: 2.1% (-1.2- 5.2%) to 4.7% (0.8-16.3%), p < 0.05. At the end of the 8 week wash-out, FMD had significantly deteriorated to 3.2% (-2.8-8.2), p < 0.05 vs. week 12 FMD, and was similar to pre-treatment values. GTN mediated dilatation was unchanged through the study. CONCLUSION: Atorvastatin significantly reduced the hyperlipidaemia of NRP. This was associated with improved conduit artery endothelial function after 12 weeks of treatment. This is consistent with the hypothesis that dyslipoproteinaemia is the primary cause of endothelial dysfunction in NRP. [source] INTEGRATING ERRORS INTO THE TRAINING PROCESS: THE FUNCTION OF ERROR MANAGEMENT INSTRUCTIONS AND THE ROLE OF GOAL ORIENTATIONPERSONNEL PSYCHOLOGY, Issue 2 2003DOERTE HEIMBECK Error management training explicitly allows participants to make errors. We examined the effects of error management instructions ("rules of thumb" designed to reduce the negative emotional effects of errors), goal orientation (learning goal, prove goal, and avoidance goal orientations) and attribute x treatment interactions on performance. A randomized experiment with 87 participants consisting of 3 training procedures for learning to work with a computer program was conducted: (a) error training with error management instructions, (b) error training without error management instructions; and (c) a group that was prevented from making errors. Results showed that short-and medium-term performance (near and far transfer) was superior for participants of the error training that included error management instructions, compared with the two other training conditions. Thus, error management instructions were crucial for the high performance effects of error training. Prove and avoidance goal orientation interacted with training conditions. [source] ,YOU MIGHT AS WELL BE HUNG FOR A SHEEP AS A LAMB': THE LOSS FUNCTION OF AN AGENT,THE MANCHESTER SCHOOL, Issue 3 2008MARGARET BRAY Most of those who take macro and monetary policy decisions are agents. The worst penalty which can be applied to these agents is to sack them. Agents thus have loss functions which are bounded above. We work with a bell loss function which has this property. With additive uncertainty the certainty equivalence which holds for a quadratic loss function breaks down with a bell loss function when there are two or more targets. With multiplicative (Brainard) uncertainty policy is more conservative than in the absence of multiplicative uncertainty, but less so with the bell than the quadratic loss function. [source] PANCREATICODUODENECTOMY WITH PANCREATICOGASTROSTOMY: ASSESSMENT OF PATIENTS' NUTRITIONAL STATUS, QUALITY OF LIFE AND PANCREATIC EXOCRINE FUNCTIONANZ JOURNAL OF SURGERY, Issue 3 2000Hock Soo Ong Background: The changes in digestive function of patients with pancreaticoduodenectomy (PD) and pancreaticogastrostomy reconstruction have not been well-documented. The present study sought to assess the nutritional status, quality of life and pancreatic exocrine function in this group of patients. Methods: The study group consisted of 11 PD with pancreaticogastrostomy patients. The control group consisted of 11 consecutive patients who had subtotal gastrectomy (SG) for distal stomach tumours. Results: The median ages for the PD and SG groups were 57 and 59 years, respectively. The median intervals between surgery to assessment were 68 and 60 weeks, respectively. The PD group attained a mean of 92.7% of their pre-surgery weight compared to 91.3% in the SG group. Both groups had a comparable gastrointestinal quality of life index and Visick scale scores. Exocrine insufficiency using the faecal chymotrypsin test was present in 36% of patients with PD. None of the patients in the SG group had exocrine insufficiency. Conclusion: Pancreaticoduodenectomy patients had a significant occurrence of pancreatic exocrine insufficiency compared to the SG group. But patients with PD and pancreaticogastrostomy reconstruction maintained a nutritional status and quality of life similar to those with curative SG for stomach malignancy. Apart from exocrine insufficiency, the concomitant gastrectomy in the PD group is an important factor responsible for their inability to gain weight. [source] NEOLITHIC ZOOMORPHIC VESSELS FROM EASTERN MACEDONIA, GREECE: ISSUES OF FUNCTION*ARCHAEOMETRY, Issue 3 2009C. MARANGOU Five fragments of Late Neolithic clay zoomorphic vessels from northern Greece have been analysed for organic residues by gas chromatography , mass spectrometry. The results showed that the containers had been used in connection with a number of substances, in particular lower terpenoids, an oil or fat, possibly fossil fuel and in one case possibly beeswax. The paper considers likely interpretations of such combinations of materials in relation to possible functions of these symbolically enhanced artefacts. It appears that substances may have been used in the vessels because of their aromatic and/or medicinal and combustible properties, possibly in order to produce light, fragrance and/or smoke. [source] THE SACRISTY OF SAN MARCO, VENICE: FORM AND FUNCTION ILLUMINATEDART HISTORY, Issue 3 2009LYDIA HAMLETT The sacristy at San Marco in Venice had a crucial functional role, both within the daily liturgical life of the basilica and especially during the ritual activity of Holy Week, which is reflected through its artistic programmes. This article focuses solely on the sacristy as a key site within the church, and its renaissance rebuilding and decoration c. 1491,1546. It examines the major elements of the programme in turn, including the mosaics, door, tarsie and tapestries. For the first time, each of these developments is viewed as complementary to a deliberate and coherent programme revolving around liturgical requirements, iconography of the Passion and overarching themes of triumph and redemption. Without surviving documentary evidence for the instigation of such a monolithic project, this article argues that the sacristy be looked at anew in light of contemporary understanding of the sacristy as a space. The practical and symbolic associations of the sacristy at San Marco are thus considered in this wider typological context in order to illuminate our own appreciation of the development of the sacristy's artistic programme. [source] A STEPWISE CONFIDENCE INTERVAL PROCEDURE BASED ON AN ASYMMETRIC LOSS FUNCTION WITH APPLICATIONS TO TOXICOLOGICAL EVALUATIONAUSTRALIAN & NEW ZEALAND JOURNAL OF STATISTICS, Issue 1 2010Jian Tao Summary The purpose of toxicological studies is a safety assessment of compounds (e.g. pesticides, pharmaceuticals, industrial chemicals and food additives) at various dose levels. Because a mistaken declaration that a really non-equivalent dose is equivalent could have dangerous consequences, it is important to adopt reliable statistical methods that can properly control the family-wise error rate. We propose a new stepwise confidence interval procedure for toxicological evaluation based on an asymmetric loss function. The new procedure is shown to be reliable in the sense that the corresponding family-wise error rate is well controlled at or below the pre-specified nominal level. Our simulation results show that the new procedure is to be preferred over the classical confidence interval procedure and the stepwise procedure based on Welch's approximation in terms of practical equivalence/safety. The implementation and significance of the new procedure are illustrated with two real data sets: one from a reproductive toxicological study on Nitrofurazone in Swiss CD-1 mice, and the other from a toxicological study on Aconiazide. [source] THERE IS WEAK EVIDENCE THAT FORCED-USE THERAPY PROVIDED FOR 1,MONTH WITHOUT ADDITIONAL THERAPY IMPROVED THE FINE MOTOR FUNCTION OF CHILDREN WITH HEMIPARESISAUSTRALIAN OCCUPATIONAL THERAPY JOURNAL, Issue 2 2004Margaret Wallen No abstract is available for this article. [source] ERECTILE FUNCTION, SEXUAL DRIVE, AND EJACULATORY FUNCTION ALTER RECONSTRUCTIVE SURGERY FOR ANTERIOR URETHRAL STRICTURE DISEASEBJU INTERNATIONAL, Issue 6 2007Javier Ponce De León No abstract is available for this article. [source] INHIBITION OF BRAIN RENIN,ANGIOTENSIN SYSTEM IMPROVES DIASTOLIC CARDIAC FUNCTION FOLLOWING MYOCARDIAL INFARCTION IN RATSCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 8 2009IG Araujo SUMMARY 1Recently, we demonstrated that oral captopril treatment improved diastolic function and attenuated cardiac remodelling after myocardial infarction (MI) in rats. Considering the feasible role of the brain renin,angiotensin system (RAS) in heart failure, in the present study we investigated the role of the captopril injected intracerebroventricularly (i.c.v.) on the progression of cardiac dysfunction. 2Male Wistar rats underwent experimental MI or sham operation. Infarcted animals received daily i.c.v. injections of captopril (approximately 200 mg/kg; MI + Cap) or saline (MI) from 11 to 18 days after infarction. Electro- and echocardiogram assessments were performed before and after i.c.v. treatment (10 and 18 days after MI, respectively). Water and hypertonic saline ingestion were determined daily between 12 and 16 days after MI. 3Electrocardiograms from the MI and MI + Cap groups showed signs that resembled large MI before and after i.c.v. treatment. However, despite similar systolic dysfunction observed in both groups, only captopril-treated rats exhibited reduced left ventricular (LV) dilatation and improved LV filling, as assessed by echocardiograms, and low levels of water ingestion compared with the saline-treated control group. 4The results of the present study suggest that the brain RAS may participate in the development of cardiac dysfunction induced by ischaemia and that inhibition of the brain RAS may provide a new strategy for the prevention of diastolic dysfunction. [source] ILLUMINATING THE STRUCTURE AND FUNCTION OF CYS-LOOP RECEPTORSCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 10 2008Stephan A Pless SUMMARY 1Cys-loop receptors are an important class of ligand-gated ion channels. They mediate fast synaptic neurotransmission, are implicated in various ,channelopathies' and are important pharmacological targets. Recent progress in X-ray crystallography and electron microscopy has provided a considerable insight into the structure of Cys-loop receptors. However, data from these experiments only provide ,snapshots' of the proteins under investigation. They cannot provide information about the various conformations the protein adopts during transition from the closed to the open and desensitized states. 2Voltage-clamp fluorometry helps overcome this problem by simultaneously monitoring movements at the channel gate (through changes in current) and conformational rearrangements in a domain of interest (through changes in fluorescence) in real time. Thus, the technique can provide information on both transitional and steady state conformations and serves as a real time correlate of the channel structure and its function. 3Voltage-clamp fluorometry experiments on Cys-loop receptors have yielded a large body of data concerning the mechanisms by which agonists, antagonists and modulators act on these receptors. They have shed new light on the conformational mobility of both the ligand-binding and the transmembrane domain of Cys-loop receptors. [source] ANABOLIC AGENTS FOR IMPROVING MUSCLE REGENERATION AND FUNCTION AFTER INJURYCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 7 2008Gordon S Lynch SUMMARY 1In the present review, we describe how muscles can be injured by external factors, internal factors or during the performance of some actions during sports. In addition, we describe the injury to a muscle that occurs when its blood supply is interrupted, an occurrence common in clinical settings. An overview of muscle regeneration is presented, as well as a discussion of some of the potential complications that can compromise successful muscle repair and lead to impaired function and permanent disability. 2Improving muscle regeneration is important for hastening muscle repair and restoring muscle function and the present review describes ways in which this can be achieved. We describe recent advances in tissue engineering that offer considerable promise for treating muscle damage, but highlight the fact that these techniques require rigorous evaluation before they can become mainstream clinical treatments. 3Growth-promoting agents are purported to increase the size of existing and newly regenerating muscle fibres and, therefore, could be used to improve muscle function if administered at appropriate times during the repair process. The present review provides an update on the efficacy of some growth-promoting agents, including anabolic steroids, insulin-like growth factor-I (IGF-I) and b2 -adrenoceptor agonists, to improve muscle function after injury. Although these approaches have clinical merit, a better understanding of the androgenic, IGF-I and b-adrenoceptor signalling pathways in skeletal muscle is important if we are to devise safe and effective therapies to enhance muscle regeneration and function after injury. [source] ROLE OF OESTROGEN IN THE CENTRAL REGULATION OF AUTONOMIC FUNCTIONCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 9 2007TM Saleh SUMMARY 1In recent years, the role of oestrogen in women's health has been a subject of considerable scientific and popular debate. There is unquestionable evidence that oestrogen has both potent and long-lasting effects on several vital organ systems, including the cardiovascular system, the autonomic nervous system and, most recently, within the central nervous system itself. 2The research and medical community continues to debate whether the benefits of oestrogen therapy outweigh the risks in the treatment of the symptoms of menopause, the attenuation of the risk for cardiovascular insults, such as stroke and heart disease, and even the retardation of the progression of Alzheimer's disease. 3The recent evidence provided by the Heart and Estrogen/Progestin Replacement Study (HERS) II clinical trial suggesting that long-term exposure to combined oestrogen and progestin in post-menopausal women who have previously had a heart attack or stroke (for secondary prevention) may actually increase their risk of a subsequent cardiovascular insult has further fuelled the debate. However, there remain considerable gaps in our knowledge with respect to the actual mechanisms by which oestrogen exerts its various beneficial effects at the cellular level for the primary prevention of cardiovascular disease. This information is essential if we are to harness the positive aspects of oestrogen therapy in such a manner as to avoid or minimize the associated risks of increased oestrogen exposure in women who we know, with some certainty, to be at an increased risk of cancers of the uterus, cervix and breast tissue. [source] HEREDITARY AND ENVIRONMENTAL INFLUENCES ON ARTERIAL FUNCTIONCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 7 2007CS Hayward SUMMARY 1With the ageing population and increasing heart failure, arterial function has been shown to contribute to cardiovascular risk because of its adverse effects on ventriculovascular coupling. Population studies have confirmed independent prognostic information of arterial stiffening on cardiovascular survival. 2The term ,arterial function' encompasses a range of phenotypes, including measures of arterial structure/remodelling, measures of arterial wall mechanics, surrogate measures of stiffness and of wave reflection. There exists significant interaction between these measures and none is truly independent of the others. Added to this complexity is the recognition that, although arterial function has a strong genetic component, quantification requires a range of techniques from twin to family and population studies. 3The contribution of heritability is often derived from statistical models with input from genomic scanning and candidate gene studies. Studies to date confirm a significant heritable component for the majority of phenotypes examined. However, it has also been recognized that the factors involved in blood pressure maintenance are likely to be separate to those in arterial structural degeneration with ageing. Candidate genes for arterial function go beyond those of the sympathetic and renin,angiotensin systems and include genes involved in signalling pathways and extracellular matrix modulation. 4The present review examines the evidence for heritability of the major arterial function phenotypes with environmental and ageing modulation. A brief overview of the impact of atherosclerotic risk factors on arterial function is included. [source] |