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Biological Underpinnings (biological + underpinning)
Selected AbstractsGenetic aspects of pathological gambling: a complex disorder with shared genetic vulnerabilitiesADDICTION, Issue 9 2009Daniela S. S. Lobo ABSTRACT Aims To summarize and discuss findings from genetic studies conducted on pathological gambling (PG). Methods Searches were conducted on PubMed and PsychInfo databases using the keywords: ,gambling and genes', ,gambling and family' and ,gambling and genetics', yielding 18 original research articles investigating the genetics of PG. Results Twin studies using the Vietnam Era Twin Registry have found that: (i) the heritability of PG is estimated to be 50,60%; (ii) PG and subclinical PG are a continuum of the same disorder; (iii) PG shares genetic vulnerability factors with antisocial behaviours, alcohol dependence and major depressive disorder; (iv) genetic factors underlie the association between exposure to traumatic life-events and PG. Molecular genetic investigations on PG are at an early stage and published studies have reported associations with genes involved in the brain's reward and impulse control systems. Conclusions Despite the paucity of studies in this area, published studies have provided considerable evidence of the influence of genetic factors on PG and its complex interaction with other psychiatric disorders and environmental factors. The next step would be to investigate the association and interaction of these variables in larger molecular genetic studies with subphenotypes that underlie PG. Results from family and genetic investigations corroborate further the importance of understanding the biological underpinnings of PG in the development of more specific treatment and prevention strategies. [source] Comprehensive linkage and linkage heterogeneity analysis of 4344 sibling pairs affected with hypertension from the Family Blood Pressure ProgramGENETIC EPIDEMIOLOGY, Issue 3 2007Tiffany A. Greenwood Abstract Linkage analyses of complex, multifactorial traits and diseases, such as essential hypertension, have been difficult to interpret and reconcile. Many published studies provide evidence suggesting that different genes and genomic regions influence hypertension, but knowing which of these studies reflect true positive results is challenging. The reasons for this include the diversity of analytical methods used across these studies, the different samples and sample sizes in each study, and the complicated biological underpinnings of hypertension. We have undertaken a comprehensive linkage analysis of 371 autosomal microsatellite markers genotyped on 4,334 sibling pairs affected with hypertension from five ethnic groups sampled from 13 different field centers associated with the Family Blood Pressure Program (FBPP). We used a single analytical technique known to be robust to interpretive problems associated with a lack of completely informative markers to assess evidence for linkage to hypertension both within and across the ethnic groups and field centers. We find evidence for linkage to a number of genomic regions, with the most compelling evidence from analyses that combine data across field center and ethnic groups (e.g., chromosomes 2 and 9). We also pursued linkage analyses that accommodate locus heterogeneity, which is known to plague the identification of disease susceptibility loci in linkage studies of complex diseases. We find evidence for linkage heterogeneity on chromosomes 2 and 17. Ultimately our results suggest that evidence for linkage heterogeneity can only be detected with large sample sizes, such as the FBPP, which is consistent with theoretical sample size calculations. Genet. Epidemiol. 2007. © 2007 Wiley-Liss, Inc. [source] Measuring the components of competition along productivity gradientsJOURNAL OF ECOLOGY, Issue 2 2007MARK V. WILSON Summary 1Controversy surrounds the measurement of competition intensity. Moreover, when biomass varies systematically along productivity and other environmental gradients, common indices of competitive outcome mask important ecological interactions. 2This study presents two indices derived from how neighbours interact with target plants. The first, relative crowding, increases directly with the abundance of neighbours present and decreases inversely with the potential size and vigour of the target plant itself. The second, interaction strength, is the integral of suppression of the target by neighbours over the range of neighbour abundance. Relative crowding and interaction strength are derived independently, but when multiplied produce the commonly used relative competitive index, showing the biological underpinnings of the relative competition index in terms of crowding and strength of interaction. Since the new indices of relative crowding and interaction strength explicitly account for the amount of neighbour biomass, they serve as a valid method to track the effects of changing habitat conditions on the components of competition. 3The new indices are applied to three published data sets. In each case, relative crowding increased with standing crop. In one case competition was reported as unchanged along a productivity gradient, whereas the new indices show that relative crowding and interaction strength both had significant patterns, but their effects were counteracting. These results do not fit current theories of competition. Further empirical studies are needed to see if competition theory needs revision. 4Separating the mechanisms of competition into relative crowding and strength of interaction reveals previously hidden patterns that help bring to light underlying processes of competition along productivity gradients. [source] Fibromyalgia,Management of a misunderstood disorderJOURNAL OF THE AMERICAN ACADEMY OF NURSE PRACTITIONERS, Issue 7 2007Education & Training Flight Commander), Erin L. Peterson RN, FNP (Major; Family Nurse Practitioner Abstract Purpose: The purpose of this article is to review (a) what is currently known about the pathophysiology of fibromyalgia (FM), (b) how to identify patients who are susceptible to this disorder, and (c) the recommended pharmacological and nonpharmacological treatment options. Data sources: Data sources include reviews and original research from scholarly journals and Internet sites. Conclusions: There are approximately 6 million individuals in the United States diagnosed with FM, making it the third most prevalent rheumatologic disorder in this country. Failure to identify a specific causal mechanism for FM has resulted in a shift in the focus of research from etiology to treatment (Baumstark & Buckelew, 2002). Based on the literature, the most successful interventions for reduction of chronic symptoms in the FM patient is a combination of education, psychological assistance, and exercise, along with medications. It is essential that nurse practitioners (NPs) understand the issues and concerns of patients afflicted with this complex disorder. Although the organic etiology of FM syndrome remains unclear, the goals of treatment are to control pain and improve adjustment, well-being, and daily functioning of these patients to the maximum extent possible. Implications for practice: NPs are in a unique position to help identify patients who may be suffering from FM or those diagnosed with FM reporting inadequate relief of symptoms. The incomplete understanding of the biological underpinnings, as well as the multiple symptoms that characterize FM syndrome, make it a challenging disorder to diagnose and treat. It takes time and patience to care for FM patients, and there are no "quick fixes." Diagnosis is made by a combination of patient history, physical examination, laboratory evaluations, and exclusion of other causes of symptoms confused with FM. Understanding the symptomology and recommended treatments will allow NPs to give appropriate care that may include making referrals for multidisciplinary treatment of these complex patients. [source] A Bayesian hierarchical mixture model for platelet-derived growth factor receptor phosphorylation to improve estimation of progression-free survival in prostate cancerJOURNAL OF THE ROYAL STATISTICAL SOCIETY: SERIES C (APPLIED STATISTICS), Issue 1 2010Satoshi Morita Summary., Advances in understanding the biological underpinnings of many cancers have led increasingly to the use of molecularly targeted anticancer therapies. Because the platelet-derived growth factor receptor (PDGFR) has been implicated in the progression of prostate cancer bone metastases, it is of great interest to examine possible relationships between PDGFR inhibition and therapeutic outcomes. We analyse the association between change in activated PDGFR (phosphorylated PDGFR) and progression-free survival time based on large within-patient samples of cell-specific phosphorylated PDGFR values taken before and after treatment from each of 88 prostate cancer patients. To utilize these paired samples as covariate data in a regression model for progression-free survival time, and be cause the phosphorylated PDGFR distributions are bimodal, we first employ a Bayesian hierarchical mixture model to obtain a deconvolution of the pretreatment and post-treatment within-patient phosphorylated PDGFR distributions. We evaluate fits of the mixture model and a non-mixture model that ignores the bimodality by using a supnorm metric to compare the empirical distribution of each phosphorylated PDGFR data set with the corresponding fitted distribution under each model. Our results show that first using the mixture model to account for the bimodality of the within-patient phosphorylated PDGFR distributions, and then using the posterior within-patient component mean changes in phosphorylated PDGFR so obtained as covariates in the regression model for progression-free survival time, provides an improved estimation. [source] Therapeutic touch and postmodernism in nursing,NURSING PHILOSOPHY, Issue 3 2001Sarah Glazer Abstract Therapeutic touch, a healing technique based upon the laying-on of hands, has found wide acceptance in the nursing profession despite its lack of scientific plausibility. Its acceptance is indicative of a broad antiscientific trend in nursing. Adherents of this movement use the jargon of postmodern philosophy to justify their enthusiasm for a variety of mystically based techniques, citing such postmodern critics of science as Derrida and Michel Foucault as well as philosophical forerunners Heidegger and Husserl. Between 1997 and 1999, 94 articles in nursing journals referred to postmodernism, according to a database search. This paper criticizes the postmodern movement for abandoning the biological underpinnings of nursing and for misreading philosophy in the service of an antiscientific world-view. It is also suggested that nursing can retain its tradition of ,caring' without abandoning the scientific method. [source] | |||||||||||||