853 resultados para HAPLOTYPES AFFECT


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The functional catechol-O-methyltransferase (COMT Val108/158Met) polymorphism has been shown to have an impact on tasks of executive function, memory and attention and recently, tasks with an affective component. As oestrogen reduces COMT activity, we focused on the interaction between gender and COMT genotype on brain activations during an affective processing task. We used functional MRI (fMRI) to record brain activations from 74 healthy subjects who engaged in a facial affect recognition task; subjects viewed and identified fearful compared to neutral faces. There was no main effect of the COMT polymorphism, gender or genotypegender interaction on task performance. We found a significant effect of gender on brain activations in the left amygdala and right temporal pole, where females demonstrated increased activations over males. Within these regions, Val/Val carriers showed greater signal magnitude compared to Met/Met carriers, particularly in females. The COMT Val108/158Met polymorphism impacts on gender-related patterns of activation in limbic and paralimbic regions but the functional significance of any oestrogen-related COMT inhibition appears modest. Copyright © 2008 CINP.

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Background: Bipolar disorder is associated with dysfunction in prefrontal and limbic areas implicated in emotional processing. Aims: To explore whether lamotrigine monotherapy may exert its action by improving the function of the neural network involved in emotional processing. Method: We used functional magnetic resonance imaging to examine changes in brain activation during a sad facial affect recognition task in 12 stable patients with bipolar disorder when medication-free compared with healthy controls and after 12 weeks of lamotrigine monotherapy. Results: At baseline, compared with controls, patients with bipolar disorder showed overactivity in temporal regions and underactivity in the dorsal medial and right ventrolateral prefrontal cortex, and the dorsal cingulate gyrus. Following lamotrigine monotherapy, patients demonstrated reduced temporal and increased prefrontal activation. Conclusions: This preliminary evidence suggests that lamotrigine may enhance the function of the neural circuitry involved in affect recognition.

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The rapid rise in schooling in developing countries in recent decades has been dramatic. However, many cross-country regression analyses of the impact of schooling on economic growth find low and insignificant coefficients. This empirical 'puzzle' contrasts with theoretical arguments that schooling, through raising human capital, should raise income levels. This paper argues that poor results are to be expected when regression samples include countries that vary greatly in their ability to use schooling productively. Data on corruption, the black market premium on foreign exchange and the extent of the brain drain for developing countries are used as indicators of an economy's productive use of schooling. Regression analysis shows that the impact of secondary schooling on economic growth is substantially higher in countries that are adjudged to use schooling productivity.

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WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT • Currently tacrolimus is the mainstay of immunosuppression for most children undergoing liver transplantation (LT). • The clinical use of this agent, however, is complicated by its various adverse effects (mainly nephrotoxicity), its narrow therapeutic-index and considerable pharmacokinetic variability. • The low and variable oral bioavailability of tacrolimus is thought to result from the action of the multidrug efflux-pump P-glycoprotein, encoded by the ABCB1 gene. WHAT THIS STUDY ADDS • A significant association between ABCB1 genetic polymorphisms and tacrolimus-associated nephrotoxicity in paediatric patients following LT is reported for the first time. Genotyping such polymorphisms may have the potential to individualize better initial tacrolimus therapy and enhance drug safety. • The long-term effect of ABCB1 polymorphisms on tacrolimus trough concentrations were investigated up to 5 years post-transplantation. A significant effect of intestinal P-glycoprotein genotypes on tacrolimus pharmacokinetics was found at 3 and 4 years post-transplantation suggesting that the effect is maintained long term. AIMS - The aim of this study was to investigate the influence of genetic polymorphisms in ABCB1 on the incidence of nephrotoxicity and tacrolimus dosage-requirements in paediatric patients following liver transplantation. METHODS - Fifty-one paediatric liver transplant recipients receiving tacrolimus were genotyped for ABCB1 C1236>T, G2677>T and C3435>T polymorphisms. Dose-adjusted tacrolimus trough concentrations and estimated glomerular filtration rates (EGFR) indicative of renal toxicity were determined and correlated with the corresponding genotypes. RESULTS - The present study revealed a higher incidence of the ABCB1 variant-alleles examined among patients with renal dysfunction (≥30% reduction in EGFR) at 6 months post-transplantation (1236T allele: 63.3% vs 37.5% in controls, P= 0.019; 2677T allele: 63.3% vs. 35.9%, p = 0.012; 3435T allele: 60% vs. 39.1%, P= 0.057). Carriers of the G2677->T variant allele also had a significant reduction (%) in EGFR at 12 months post-transplant (mean difference = 22.6%; P= 0.031). Haplotype analysis showed a significant association between T-T-T haplotypes and an increased incidence of nephrotoxicity at 6 months post-transplantation (haplotype-frequency = 52.9% in nephrotoxic patients vs 29.4% in controls; P= 0.029). Furthermore, G2677->T and C3435->T polymorphisms and T-T-T haplotypes were significantly correlated with higher tacrolimus dose-adjusted pre-dose concentrations at various time points examined long after drug initiation. CONCLUSIONS - These findings suggest that ABCB1 polymorphisms in the native intestine significantly influence tacrolimus dosage-requirement in the stable phase after transplantation. In addition, ABCB1 polymorphisms in paediatric liver transplant recipients may predispose them to nephrotoxicity over the first year post-transplantation. Genotyping future transplant recipients for ABCB1 polymorphisms, therefore, could have the potential to individualize better tacrolimus immunosuppressive therapy and enhance drug safety.

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Aims To review the role of cardiovascular disease and therapy in the onset and recurrence of preretinal/vitreous haemorrhage in diabetic patients. Methods Retrospective case note analysis of diabetic patients with vitreous haemorrhage from the Diabetic Eye Clinic at Birmingham Heartlands Hospital. Results In total, 54 patients (mean age 57.1, 37 males, 20 type I vs34 type II diabetic patients) were included. The mean (SD) duration of diagnosed diabetes at first vitreous haemorrhage was significantly longer, 21.9 (7.6) years for type I and 14.8 (9.3) years for type II diabetic patients (P<0.01, unpaired t-test, two-tailed). Aspirin administration was not associated with a significantly later onset of vitreous haemorrhage. Four episodes were associated with ACE-inhibitor cough. There was a trend towards HMGCoA reductase inhibitor (statin) use being associated with a delayed onset of vitreous haemorrhage: 21.4 years until vitreous haemorrhage (treatment group) vs 16.2 years (nontreatment group) (P=0.09, two-tailed, unpaired t-test, not statistically significant). During follow-up 56 recurrences occurred, making a total of 110 episodes of vitreous haemorrhage in 79 eyes of 54 patients. The mean (range) follow-up post haemorrhage was 1067 (77–3842) days, with an average of 1.02 recurrences. Age, gender, diabetes type (I or II) or control, presence of hypertension or hypercholesterolaemia, and macrovascular complications were not associated with a significant effect on the 1-year recurrence rate. Aspirin (and other antiplatelet or anticoagulant agents) and ACE- inhibitors appeared to neither increase nor decrease the 1-year recurrence rate. However, statin use was significantly associated with a reduction in recurrence (Fisher exact P<0.05; two-tailed) with an odds ratio (95% CI) of 0.25 (0.1–0.95). Conclusion In this retrospective analysis, the onset of preretinal/vitreous haemorrhage was not found to be accelerated by gender, hypertension, hypercholesterolaemia, evidence of macrovascular disease, or HbA1c. Neither aspirin nor ACE-inhibitor administration accelerated the onset or recurrence of first vitreous haemorrhage. Statins may have a protective role, both delaying and reducing the recurrence of haemorrhage.

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Trust is a critical component of successful e-Commerce. Given the impersonality, anonymity, and automation of transactions, online vendor trustworthiness cannot be assessed by means of body language and other environmental cues that consumers typically use when deciding to trust offline retailers. It is therefore essential that the design of e-Commerce websites compensate by incorporating circumstantial cues in the form of appropriate trust triggers. This paper presents and discusses the results of a study which took an initial look at whether consumers with different personality types (a) are generally more trusting and (b) rely on different trust cues during their assessment of first impression vendor trustworthiness in B2C e-Commerce.

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Vascular dysfunction is one of the major causes of cardiovascular (CV) mortality and increases with age. Epidemiological studies suggest that Mediterranean diets and high nut consumption reduce CV disease risk and mortality while increasing plasma α-tocopherol. Therefore, we have investigated whether almond supplementation can improve oxidative stress markers and CV risk factors over 4 weeks in young and middle-aged men. Healthy middle-aged men (56 ± 5.8 years), healthy young men (22.1 ± 2.9 years) and young men with two or more CV risk factors (27.3 ± 5 years) consumed 50 g almond/day for 4 weeks. A control group maintained habitual diets over the same period. Plasma α-tocopherol/cholesterol ratios were not different between groups at baseline and were significantly elevated by almond intervention with 50 g almond/day for 4 weeks (p < 0.05). Plasma protein oxidation and nitrite levels were not different between groups whereas, total-, HDL- and LDL-cholesterols and triglycerides were significantly higher in healthy middle-aged and young men with CV risk factors but were not affected by intake. In the almond-consuming groups, flow-mediated dilatation (FMD) improved and systolic blood pressure reduced significantly after 50 g almonds/day for 4 weeks, but diastolic blood pressure reduced only in healthy men. In conclusion, a short-term almond-enriched diet can increase plasma α-tocopherol and improve vascular function in asymptomatic healthy men aged between 20 and 70 years without any effect on plasma lipids or markers of oxidative stress. © 2014 Informa UK, Ltd.

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The objectives of the experiment were to assess the impact of nitrogen (N) and potassium (K) fertiliser application on the cell wall composition and fast-pyrolysis conversion quality of the commercially cultivated hybrid Miscanthus x giganteus. Five different fertiliser treatments were applied to mature Miscanthus plants which were sampled at five intervals over a growing season. The different fertiliser treatments produced significant variation in concentrations of cell wall components and ash within the biomass and affected the composition and quality of the resulting fast-pyrolysis liquids. The results indicated that application of high rates of N fertiliser had a negative effect on feedstock quality for this conversion pathway: reducing the proportion of cell wall components and increasing accumulation of ash in the harvested biomass. No exclusive effect of potassium fertiliser was observed. The low-N fertiliser treatment produced high quality, low ash-high lignin biomass most suitable as a feedstock for thermo-chemical conversion. © 2010.

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A virtuális szociális világok, úgy mint a Second Life, egyre nagyobb népszerűségre téve szert, hamar az üzleti érdeklődés középpontjában találták magukat. A szerző célja, hogy feltérképezze a virtuális identitás és a fogyasztói magatartás közötti kapcsolat mibenlétét a Second Life világában. Ezért először bemutatja, hogy miként működik a Second Life és milyen jellemzőkkel rendelkezik. Másodszor ismerteti, hogy az on-line identitásalkotás miként befolyásolja üzleti szempontból az individuális viselkedést. A Second Life vizsgálata során a virtuális identitás fogalmát használja föl, mely összevethető az egyén valódi életbeli identitásával. Harmadszor: rátér a kutatási részre, amely során a Second Life világában kialakított identitás jellemzőit vizsgálta. Négy virtuális identitástípust azonosított, melyeknek más és más kapcsolata van a virtuális fogyasztás jelenségével. Végezetül: kiemeli azokat az eredményeket és megállapításokat, melyeket a vállalatoknak különösképpen figyelembe kell venniük a pszichológiai nézőpont szempontjából ahhoz, hogy eredményesen szerepeljenek a virtuális világokban. ________ Given their increasing popularity, virtual worlds, such as Second Life, attracted the attention of the business media. The aim of the present article is to explore the relationship between virtual identity and consumer behaviour in Second Life. First, the author reviews Second Life functions and particular characteristics. Second, he illustrates how online identity construction affects one’s behaviour in such environments from a business perspective. Third, the author demonstrates his findings associated with identity construction in Second Life. More specifically, four different types of virtual identities can be identified, each with slightly different implications toward virtual consumption. Finally, he highlights the major points to which companies should pay particular attention in their virtual social world activities, focusing on the psychological mechanisms that influence people’s online behaviour and thinking.

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Iridescent blue leaf coloration in four Malaysian rain forest understory plants, Diplazium tomentosum Bl. (Athyriaceae), Lindsaea lucida Bi. (Lindsaeaceae), Begonia pavonina Ridl. (Begoniaceae), and Phyllagathis rotundifolia Bl. (Melastoma- taceae) is caused by a physical effect, constructive interference of reflected blue light. The ultrastructural basis for this in D. tomentosum and L. lucida is multiple layers of cellulose microfibrils in the uppermost cell walls of the adaxial epidermis. The helicoidal arrangement of these fibrils is analogous to that which produces a similar color in arthropods. In B. pavonina and P. rotundifolia the blue-green coloration is caused by parallel lamellae in specialized plastids adjacent to the abaxial wall of the adaxial epidermis. The selective advantage of this color production, if any, is unknown.

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It was hypothesized that making a commute elevates blood pressure, causes negative affect, reduces frustration tolerance, and impairs performance on simple and complex cognitive tasks. This hypothesis was tested by varying choice and type of commute in an experiment in which 168 volunteers were randomly assigned to one of six experimental conditions. The behavior of subjects who drove 30 miles or rode on a bus for the same distance were compared with the reactions of students who did not commute. Multivariate analyses of variance indicated that subjects who made the commute showed lower frustration tolerance and deficits on complex cognitive task performance. Commuting also raised pulse and systolic blood pressure. Multivariate analyses of covariance (MANCOVA) were performed in an effort to identify physiological and emotional reactions that may mediate these relations. No mediational relationships were uncovered. ^

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DNA serves as a target molecule for several types of enzymes and may assume a wide variety of structural motifs depending upon the local sequence. The BssHII restriction site (GC)3 resides in a 9bp region of alternating pyrimidine and purine residues within the &phis;X174 genome. Such sequences are known to demonstrate non-canonical helical behavior under the appropriate conditions. The kinetics of BssHII cleavage was investigated in supercoiled and linear plasmid DNA, and in a 323bp DNA fragment obtained via amplification of &phis;X174. The rate of enzyme cleavage was enhanced in the supercoiled form and in the presence of 50μM cobalt hexamine. Similarly, cobalt hexamine was also found to enhance TaqI activity directly adjacent to the (GC)3 region. ^ Initial DNA polymerase I binding studies (including a gel mobility shift assay and a protection assay) indicated a notable interaction between DNA polymerase I and the BssHII site. An in-depth study revealed that equilibrium binding of DNA polymerase I to the T7 RNA polymerase promoter was comparable to that of the (GC)3 site, however the strongest interaction was observed with a cruciform containing region. Increasing the ionic strength of the solution environment, including the addition of DNA polymerase I reaction buffer significantly decreased the equilibrium dissociation constant values. ^ It is suggested that the region within or around the BssHII site experiences a conformational change generating a novel structure under the influence of supercoiled tension or 50μM cobalt hexamine. It is proposed that this transition may enhance enzyme activity and binding by providing an initial enzyme-docking site—the rate-limiting step in restriction enzyme kinetics. The high binding potential of DNA polymerase I for each of the motifs described, is hypothesized to be due to recognition of the structural DNA anomalies by the 3′–5′ exonuclease domain. ^

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The purpose of this qualitative study was to explore the academic and nonacademic experiences of self-identified first-generation college students who left college before their second year. The study sought to find how the experiences might have affected the students' decision to depart. The case study method was used to investigate these college students who attended Florida International University. Semi-structured interviews were conducted with six ex-students who identified themselves as first-generation college students. The narrative data from the interviews were transcribed, coded, and analyzed. Analysis was informed by Pascarella, Pierson, Wolniak, and Terenzini's (2004) theoretical framework of important college academic and nonacademic experiences. An audit trail was kept and the data was triangulated by using multiple sources to establish certain findings. The most critical tool for enhancing trustworthiness was the use of member checking. I also received ongoing feedback from my major professor and committee throughout the dissertation process. The participants reported the following academic experiences: (a) patterns of coursework; (b) course-related interactions with peers; (c) relationships with faculty; (d) class size; (e) academic advisement; (f) orientation and peer advisors; and (e) financial aid. The participants reported the following nonacademic experiences; (f) on- or off- campus employment; (g) on- or off-campus residence; (h) participation in extracurricular activities; (i) noncourse-related peer relationships; (j) commuting and parking; and (k) FIU as an HSI. Isolationism and poor fit with the university were the most prevalent reasons for departure. The reported experiences of these first-generation college students shed light on those experiences that contributed to their departure. University administrators should give additional attention to these stories in an effort to improve retention strategies for this population. All but two of the participants went on to enroll in other institutions and reported good experiences with their new institutions. Recommendations are provided for continued research concerning how to best meet the needs of college students like the participants; students who have not learned from their parents about higher education financial aid, academic advisement, and orientation.

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Research indicates that people engaged in legal decision-making use a host of biases and preconceptions to guide their decisions about whether the evidence presented to them is reasonable. However, few theories address how such expectations affect legal decision-makers. The present study attempted to determine if social judgment theory (SJT) can explain how and when legal decision-makers rely on expectations for the complainant's psychological injury in a hostile environment sexual harassment case. Two experiments provided undergraduate participants with a written summary of a hostile work environment allegation that first manipulated participants' expectations about reasonable psychological injuries (mild v. severe), and then presented them with actual severity levels of psychological injury (ranging from minimal to extreme). Experiment 1 (N = 295) hypothesized and found that participants who expected severe injuries perceived a greater range of psychological injuries to be reasonable than participants expecting mild injury. Experiment 2 ( N = 202) used similar methodology and investigated whether perceived reasonableness for the injury allegations affected legal decisions. Experiment 2 hypothesized that participants expecting severe psychological injury should render more pro-complainant decisions than participants expecting mild psychological injury. This result should be most pronounced when participants receive a moderate injury allegation, since this allegation was perceived as reasonable by participants expecting severe injury, but unreasonable by participants expecting mild injury. Consistent with SJT, participants who received a moderate injury but expected a severe injury found more liability than participants who received a moderate injury but expected a mild injury. Inconsistent with SJT, participants' expectations did not affect their compensatory damage decisions. In fact, more severe injury allegations increased damage awards regardless of participants' expectations. Although the results provide mixed support for applying SJT to legal decisions in sexual harassment cases, they emphasize the continuing role of oft-unstudied extra-legal factors (juror's expectations and psychological injury severity) on legal decisions.

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Seascape ecology provides a useful framework from which to understand the processes governing spatial variability in ecological patterns. Seascape context, or the composition and pattern of habitat surrounding a focal patch, has the potential to impact resource availability, predator-prey interactions, and connectivity with other habitats. For my dissertation research, I combined a variety of approaches to examine how habitat quality for fishes is influenced by a diverse range of seascape factors in sub-tropical, back-reef ecosystems. In the first part of my dissertation, I examined how seascape context can affect reef fish communities on an experimental array of artificial reefs created in various seascape contexts in Abaco, Bahamas. I found that the amount of seagrass at large spatial scales was an important predictor of community assembly on these reefs. Additionally, seascape context had differing effects on various aspects of habitat quality for the most common reef species, White grunt Haemulon plumierii. The amount of seagrass at large spatial scales had positive effects on fish abundance and secondary production, but not on metrics of condition and growth. The second part of my dissertation focused on how foraging conditions for fish varied across a linear seascape gradient in the Loxahatchee River estuary in Florida, USA. Gray snapper, Lutjanus griseus, traded food quality for quantity along this estuarine gradient, maintaining similar growth rates and condition among sites. Additional work focused on identifying major energy flow pathways to two consumers in oyster-reef food webs in the Loxahatchee. Algal and microphytobenthos resource pools supported most of the production to these consumers, and body size for one of the consumers mediated food web linkages with surrounding mangrove habitats. All of these studies examined a different facet of the importance of seascape context in governing ecological processes occurring in focal habitats and underscore the role of connectivity among habitats in back-reef systems. The results suggest that management approaches consider the surrounding seascape when prioritizing areas for conservation or attempting to understand the impacts of seascape change on focal habitat patches. For this reason, spatially-based management approaches are recommended to most effectively manage back-reef systems.