			Home About us Contact

Consistent Evidence (consistent + evidence)

Distribution by Scientific Domains

Medical Sciences	63%
Life Sciences	15%
Psychology	9%
4 Other Domains	13%

Selected Abstracts

Functional magnetic resonance imaging of the human brain and spinal cord by means of signal enhancement by extravascular protons

CONCEPTS IN MAGNETIC RESONANCE, Issue 1 2003
P.W. Stroman
Abstract A review of functional magnetic resonance imaging (fMRI) signal changes in spin,echo image data is presented. Spin,echo fMRI data from the human brain and spinal cord show a consistent departure from that expected with blood oxygen level dependent (BOLD) contrast. Studies to investigate this finding demonstrate fMRI signal changes of 2.5% in the spinal cord and 0.7% in the brain at 1.5 T, which is extrapolated to an echo time of zero. Consistent evidence of a non-BOLD contrast mechanism arising from a proton-density change at sites of neuronal activation is demonstrated. A mathematical model and physiological explanation for signal enhancement by extravascular protons is also presented. © 2003 Wiley Periodicals, Inc. Concepts Magn Reson 16A: 28,34, 2003 [source]

A taxometric study of alcohol abuse and dependence in a general population sample: evidence of dimensional latent structure and implications for DSM-V

ADDICTION, Issue 5 2009
Tim Slade
ABSTRACT Aims To explore, with the aid of taxometric analysis, whether alcohol abuse and alcohol dependence are each conceptualized most effectively as single latent dimensions or distinct latent categories. Design Data were taken from a nationally representative cross-sectional epidemiological survey of psychiatric and substance use disorders. Setting General population of Australia. Participants A subsample of all respondents who had consumed at least 12 drinks in the year prior to the survey and who had consumed at least three drinks on at least one single day (n = 4920 of a possible 10 641). Measurements DSM-IV criteria for alcohol abuse and dependence were assessed with the Composite International Diagnostic Interview, version 2.1. Two independent taxometric procedures, MAXimum EIGenvalue (MAXEIG) and mean above minus below a cut (MAMBAC), together with analysis of simulated dimensional and categorical data sets, were carried out. Findings Consistent evidence was found for a single latent dimension underlying the symptoms of alcohol dependence. Less consistent evidence of dimensionality was found for the symptoms of alcohol abuse. Conclusions These findings support the growing consensus regarding the need for continuous measures of alcohol use disorders to complement the traditional categorical representations in upcoming versions of the major psychiatric classification systems. [source]

THE EARNINGS EFFECT OF EDUCATION AT COMMUNITY COLLEGES

CONTEMPORARY ECONOMIC POLICY, Issue 1 2010
DAVE E. MARCOTTE
In this paper, I make use of data from the 2000 follow-up of the National Education Longitudinal Survey postsecondary education transcript files to extend what is known about the value of education at community colleges. I examine the effects of enrollment in community colleges on students' subsequent earnings. I estimate the effects of credits earned separately from credentials because community colleges are often used as a means for students to engage in study not necessarily leading to a degree or certificate. I find consistent evidence of wage and salary effects of both credits and degrees, especially for women. There is no substantial evidence that enrollment in vocational rather than academic coursework has a particularly beneficial effect, however. (JEL I2, J24) [source]

Drug prevention programmes for young people: where have we been and where should we be going?

ADDICTION, Issue 10 2010
Richard Midford
ABSTRACT Aim Substance use by young people has long been a concern of western society, but opinion is mixed as to which prevention approach offers the greatest benefit, and whether indeed there is any benefit at all. This paper reviews the nature of prevention programmes, the research evidence that underpins these programmes and the prevention objectives against which effectiveness is measured. The aim of this is to create better understanding of the elements that maximize programme effectiveness, what can be achieved by prevention programmes and how programmes can be improved. Findings There is a range of prevention approaches for which there is evidence of effectiveness. Some are classroom-based; some focus upon parenting; some have substantial whole-of-school and community elements; and some target risk and protective factors in early childhood. All, however, are based substantially on the social influence model. In an attempt to improve practice lists of effective programmes have been developed, but there are concerns about the science behind selection. On balance, there is consistent evidence that social influence prevention programmes do have a small, positive effect on drug use, but this then raises the question as to whether harm, rather than use, would be the more worthwhile target for prevention. Prevention that seeks to reduce harm has been demonstrably effective, but has found little support in some jurisdictions. Conclusion Research has created a progressively better understanding of how to optimize programme effectiveness and what can be achieved realistically by even the most effective programmes. However, further research is required to identify which, if any, particular approach offers greater promise. The effectiveness of harm reduction should be compared with more traditional abstinence and the additional effects of whole of school, parent and community elements need to be measured more accurately. Contemporary social influence prevention programmes are flawed, but the approach is still the best way of influencing drug use behaviour in young people as a whole. Evidence-based refinement is the best option for greater benefit. [source]

The impact of cigarette deprivation and cigarette availability on cue,reactivity in smokers

ADDICTION, Issue 2 2010
Steffani R. Bailey
ABSTRACT Aims This experiment was conducted to determine the impact of cigarette deprivation and cigarette availability on reactivity measures to cigarette cues. Participants Smokers were recruited who were 18 years of age or older, not attempting to quit or cut down on their smoking, smoked at least 20 cigarettes daily, had been smoking regularly for past year and had an expired carbon monoxide level of at least 10 parts per million. Design Smokers were assigned randomly to abstain from smoking for 24 hours (n = 51) or continue smoking their regular amount (n = 50). Twenty-four hours later, they were exposed to trials of either a lit cigarette or a glass of water with a 0, 50 or 100% probability of being able to sample the cue on each trial. Craving, mood, heart rate, skin conductance, puff topography and latency to access door to sample the cue were measured. Findings Both exposure to cigarette cues and increasing availability of those cues produced higher levels of craving to smoke. Deprivation produced a generalized increase in craving. There was no consistent evidence, however, that even under conditions of high cigarette availability, deprived smokers were sensitized selectively to presentations of cigarette cues. Conclusions The data suggest that, even under conditions of immediate cigarette availability, deprivation and cue presentations have independent, additive effects on self-reported craving levels in smokers. [source]

Mechanisms of change in motivational interviewing: a review and preliminary evaluation of the evidence

ADDICTION, Issue 5 2009
Timothy R. Apodaca
ABSTRACT Aims Motivational interviewing (MI) is an efficacious treatment for substance use disorders. However, little is known about how MI exerts its therapeutic effects. This review is a first attempt to summarize and evaluate the evidence for purported within-session mechanisms of change. The primary question of interest was: which MI constructs and variables appear to be the most promising candidates for mechanisms of change? Methods Literature searches were conducted to identify studies delivering MI in an individual format for the treatment of substance use disorders. Our search identified a total of 152 studies for review; 19 studies met inclusion criteria by providing data on at least one link in the causal chain model under examination. Effect size estimates were calculated for every possible step in the causal model where sufficient data were provided by study authors. Results Four constructs of therapist behavior were evaluated: MI-Spirit, MI-Consistent behaviors, MI-Inconsistent behaviors and therapist use of specific techniques. Five constructs of client behavior were evaluated: change talk/intention, readiness to change, involvement/engagement, resistance and the client's experience of discrepancy. The absence of experimental and full mediation studies of mechanisms of change was notable. Effect sizes were generally mixed. Conclusions The most consistent evidence was found for three constructs: client change talk/intention (related to better outcomes); client experience of discrepancy (related to better outcomes); and therapist MI-Inconsistent behavior (related to worse outcomes). Regarding therapist use of specific techniques, use of a decisional balance exercise showed the strongest association to better outcomes. [source]

A taxometric study of alcohol abuse and dependence in a general population sample: evidence of dimensional latent structure and implications for DSM-V

Improving clinical assessment: evaluating students' ability to identify and apply clinical criteria

EUROPEAN JOURNAL OF DENTAL EDUCATION, Issue 3 2010
C. Redwood
Abstract Aim:, There is ongoing concern by health educators over the inability of professionals to accurately self-assess their clinical behaviour and standards, resulting in doubts over a key expectation of effective self-regulation in the health professions. Participation by students in the assessment process has been shown to increase the understanding of assessment criteria in written assessment tasks. How this might transfer to the clinical setting is the focus of this study. This paper is part of an ongoing investigation of the impact on learning of a series of activities that provides students with opportunities to discuss and apply criteria and standards associated with self-assessment in clinical dentistry. Our aim was to evaluate whether participation in these assessment activities improved the ability of first-year dental students to recognise behaviours demonstrated by ,peers' in videos of clinical scenarios and to relate these to the assessment criteria. Materials and methods:, A series of three workshops in conjunction with weekly clinical assessment activities in Semesters 1 and 2 were use to support first-year students' learning of clinical assessment criteria. The design of the workshops was based on the principles of social constructivist theories of learning and the concept of tacit knowledge. Accordingly workshop activities were planned around videos that were specifically constructed to illustrate procedures and behaviours typical of those observed by staff and tutors in the first year of the dental course at The University of Adelaide, Australia. First-year students viewed the videos prior to and after the workshops and recorded observed behaviours that related to the assessment criteria that were used in their clinical practice course. Student learning outcomes were assessed 10,14 weeks after the initial workshop and again up to 42 weeks later. To check whether learning resulted from repeated viewing of the videos without formal discussion, a reference group of third-year students who did not attend the workshops also viewed the videos two times, separated by 12 weeks, and recorded observations in the same way. Results:, There was no consistent evidence that repeat viewing of the videos in isolation resulted in improved recognition of ,peer' behaviours by third-year dental students. Results for the first-year students indicated that the workshops and clinical assessment activities had a significantly positive effect on the ability of students to identify ,peer' behaviours related to the criteria used for clinical assessment. In particular, students' recognition in others of knowledge and professional behaviours improved significantly. This improvement was retained over the year and students were able to recognise these behaviours in other scenarios relevant to their year level. Conclusions:, This early exposure to the process of clinical assessment, coupled with ongoing self-assessment and tutor feedback throughout first year, improved the ability of first-year students to identify and apply some key assessment criteria to observed ,peer' behaviour, and this ability was retained over time. [source]

"When passion breeds justice": procedural fairness effects as a function of authority's passion

EUROPEAN JOURNAL OF SOCIAL PSYCHOLOGY, Issue 3 2009
David De Cremer
The present research examined how procedural fairness predicts negative emotions and withdrawal behavior as a function of authority's display of passion. A first study revealed that reinforcing the concept of passion made the concept of justice and fairness more accessible to participants, as such suggesting that authority passion should make people focus more on procedural fairness information. Corroborating this line of reasoning, a scenario experiment and a laboratory experiment thereafter yielded consistent evidence that the effects of procedural fairness (i.e., voice vs. no voice) were stronger on negative emotions and willingness to withdraw when the authority was passionate relative to not being passionate. In addition, the results of both studies also revealed that negative emotions mediated the effect of procedural fairness on withdrawal, but only so when the authority was passionate (i.e., mediated moderation). It is concluded that more research is needed focusing on the interactions between different authority styles/characteristics and procedural fairness effects. Copyright © 2008 John Wiley & Sons, Ltd. [source]

Litter species composition influences the performance of seedlings of grassland herbs

FUNCTIONAL ECOLOGY, Issue 3 2006
H. QUESTED
Summary 1This study examines the impacts of plant litter species identity and the composition of litter mixtures on seedling recruitment in the context of land-use change (abandonment) in conservationally important southern Swedish semi-natural grasslands. 2We found that plant litter had marked positive effects on the seedling recruitment of two common grassland species, and that these effects varied strongly with the species identity of the litter. 3There was no consistent evidence that litters of species typical of earlier succession had a greater positive impact on recruitment than those typical of late succession. 4The impact of mixtures of the five litter types examined was generally as expected based on the impacts of single-species litters and their contribution to the litter mixture, as predicted by the biomass ratio hypothesis. However, this was not the case for all litter and seedling species combinations, and some interactions were evident. 5Species identity of litter is important even in multispecies litter mixtures. Changes in plant species dominance (and hence the proportions of litter of different species), as a result of shifts in land use, are likely to result in changes in seedling performance, with potential consequences for the persistence of plant populations in former semi-natural grasslands. [source]

Maternal employment and overweight children: does timing matter?

HEALTH ECONOMICS, Issue 8 2008
Stephanie von Hinke Kessler Scholder
Abstract Recent literature has shown consistent evidence of a positive relationship between maternal employment and children's overweight status. These studies largely use average weekly work hours over the child's life to measure employment. This paper specifically aims at exploring the importance of the timing of employment. Using various econometric techniques to control for observable and unobservable child and family characteristics, the results show that full-time maternal employment during mid-childhood positively affects the probability of being overweight at age 16. There is no evidence that part-time or full-time employment at earlier/later ages affects this probability. Copyright © 2008 John Wiley & Sons, Ltd. [source]

The association of use of sunbeds with cutaneous malignant melanoma and other skin cancers: A systematic review

INTERNATIONAL JOURNAL OF CANCER, Issue 5 2007
Article first published online: 27 NOV 200
Abstract Exposure to solar ultraviolet (UV) radiation is a known cause of skin cancer. Sunbed use represents an increasingly frequent source of artificial UV exposure in light-skinned populations. To assess the available evidence of the association between sunbed use and cutaneous malignant melanoma (melanoma) and other skin cancers, a systematic review of the literature till March 2006 on epidemiological and biological studies on sunbed use was performed in Pubmed, ISI Web of Science, Embase, Pascal, Cochrane library, Lilacs and Medcarib. Search for keywords in the title and in the abstract was done systematically and supplemented by manual searches. Only case,control, cohort or cross-sectional studies were selected. Data were abstracted by means of a standardized data-collection protocol. Based on 19 informative studies, ever-use of sunbeds was positively associated with melanoma (summary relative risk, 1.15; 95% CI, 1.00,1.31), although there was no consistent evidence of a dose,response relationship. First exposure to sunbeds before 35 years of age significantly increased the risk of melanoma, based on 7 informative studies (summary relative risk, 1.75; 95% CI, 1.35,2.26). The summary relative risk of 3 studies of squamous cell carcinoma showed an increased risk. For basal cell carcinoma, the studies did not support an association. The evidence does not support a protective effect of the use of sunbeds against damage to the skin from subsequent sun exposure. Young adults should be discouraged from using indoor tanning equipment and restricted access to sunbeds by minors should be strongly considered. © 2006 Wiley-Liss, Inc. [source]

Dietary acrylamide and human cancer

INTERNATIONAL JOURNAL OF CANCER, Issue 2 2006
Claudio Pelucchi
Abstract Low levels of acrylamide have been found in several foods cooked at high temperatures. While there is sufficient evidence for the carcinogenicity of acrylamide in experimental animals, the few epidemiologic studies conducted to date on occupational and dietary exposure to acrylamide have found no consistent evidence of association with human cancer risk. Using data from an integrated network of Italian and Swiss hospital-based case-control studies, we analyzed the relation between dietary acrylamide intake and cancers of the oral cavity and pharynx (749 cases, 1,772 controls), esophagus (395 cases, 1,066 controls), large bowel (1,394 cases of colon, 886 cases of rectal cancer, 4,765 controls), larynx (527 cases, 1,297 controls), breast (2,900 cases, 3,122 controls), ovary (1,031 cases, 2,411 controls) and prostate (1,294 cases, 1,451 controls). All the studies included incident, histologically confirmed cancer cases and controls admitted to the same network of hospitals for acute nonneoplastic conditions. We calculated odds ratios (ORs) using multivariate logistic regression models, adjusted for energy intake and other major covariates of interest. The ORs for the highest versus the lowest quintile of acrylamide intake were 1.12 (95% CI = 0.76,1.66) for cancer of the oral cavity/pharynx, 1.10 (95% CI = 0.65,1.86) for esophageal, 0.97 (95% CI = 0.80,1.18) for colorectal, 1.23 (95% CI = 0.80,1.90) for laryngeal, 1.06 (95% CI = 0.88,1.28) for breast, 0.97 (95% CI = 0.73,1.31) for ovarian and 0.92 (95% CI = 0.69,1.23) for prostate cancer. None of the trend in risk was significant. This uniquely large and comprehensive data set does not show any consistent association between intake of acrylamide and the risk of breast and several other common cancers. © 2005 Wiley-Liss, Inc. [source]

Inpatient falls in adult acute care settings: influence of patients' mental status

JOURNAL OF ADVANCED NURSING, Issue 8 2010
Huey-Ming Tzeng
tzeng h.-m. (2010) Inpatient falls in adult acute care settings: influence of patients' mental status. Journal of Advanced Nursing,66(8), 1741,1746. Abstract Title.,Inpatient falls in adult acute care settings: influence of patients' mental status. Aim., This paper is a report of a study of fallers' mental status as one of the patient-related intrinsic risk factors for falls. Background., Whether confusion is one of the most important risk factors associated with risk of falling in hospital settings is unclear. Literature reviews have not identified consistent evidence for effective preventive interventions for patients with mental status deficits. Methods., This retrospective research was conducted in six adult acute care units in a community hospital in the United States of America. The data source was the 1017 fall incidents occurring between 1 July 2005 and 30 April 2009. Descriptive statistics and Pearson chi-square tests were used to analyse the data. Results., The presence of mental status deficits was identified as the dominant issue in 346 (34%) falls. The group of fallers with mental status deficits (32·1%, n = 111) seemed to have fewer toileting-related falls than those without mental status deficits (46·7%, n = 314). Fallers with mental status deficits tended to have more severe fall injuries than those without mental status deficits (,2 = 10·08, d.f. = 3, P = 0·018). Conclusion., Risk assessment and targeted surveillance should be used as part of falls prevention policy. Involving nursing staff and family members in assessing a patient's mental status may help to prevent falls caused by mental status deficits. [source]

Comparison of the specificity and sensitivity of traditional methods for assessment of nephrotoxicity in the rat with metabonomic and proteomic methodologies

JOURNAL OF APPLIED TOXICOLOGY, Issue 4 2005
Andy Gibbs
Abstract There is currently a great deal of scientific interest and debate concerning the possible advantages that proteomic and metabonomic technologies might have over traditional biomarkers of toxicity (blood and urine chemistry, histopathology). Numerous papers have been published that make impressive claims concerning potential applications for these novel technologies, however there appears to be little hard evidence in the literature of their advantages over the traditional techniques for assessing toxicity. The aim of this review was to evaluate the relative sensitivity and specificity of proteomic and metabonomic techniques, compared with traditional techniques, for assessing xenobiotic-induced nephrotoxicity. A review of studies was performed where both one of the novel methods as well as traditional techniques were used for assessment of xenobiotic-induced nephrotoxicity. There was no consistent evidence from the literature that the novel methodologies were any more sensitive than the traditional methods for assessing nephrotoxicity. This could be due to the relatively small number of studies available for review (n = 13), the fact that generally these studies were not aimed at determining relative sensitivity or specificity and may not be the case with other target organs, such as the liver. However, it was clear that the novel methodologies were able to discriminate between the effects caused by different toxicants. There was evidence both that this discrimination was on the basis of different mechanisms of toxicity and on the basis of different locations of nephrotoxic lesion. A great deal of validation work is necessary before these techniques could gain full acceptance by regulatory authorities, and it is unclear whether their use in anything other than non-regulatory, mechanistic studies is likely to become widespread. Copyright © 2005 John Wiley & Sons, Ltd. [source]

Migration strategies of sylviid warblers: chance patterns or community dynamics?

JOURNAL OF AVIAN BIOLOGY, Issue 1 2000
Peter Howlett
The effects of community dynamics in birds on the optimisation of their migratory strategies is a neglected area. For three years, we captured migrating warblers on autumn passage at a coastal site in western Britain. We used canonical correspondence analysis (CCA) to assess spatio-temporal patterns of occurrence, and principal components analysis (PCA) to assess morphological variation. We calculated Euclidean distance in ordination and morphological space to assess separation between species pairs, and used Monte-Carlo simulations to assess the probability of pattern occurring by chance. Ordination revealed five species-groups separated by habitat type and time of passage. Reed Warbler Acrocephalus scirpaceus and Sedge Warbler A. schoenobaenus (Group 1) occurred in wet habitats and peaked simultaneously. In drier habitats with scrub, a first wave of Blackcap Sylvia atricapilla (Group 2) significantly preceded Grasshopper Warbler Locustella naevia, Willow Warbler Phylloscopus trochilus, Whitethroat Sylvia communis and Lesser Whitethroat Sylvia curruca (Group 3), which in all but one case (Lesser Whitethroat) significantly preceded Garden Warbler Sylvia borin (Group 4); peak numbers of Chiffchaffs Phylloscopus collybita and a second wave of Blackcaps (Group 5) occurred later still. Age effects were found only in Acrocephalus, with adults peaking before juveniles. For seven out of eight pairings within genera, separation in time of passage increased significantly in species that were morphologically similar. The only exception was Blackcap and Lesser Whitethroat which differed substantially in both passage time and morphology. Monte-Carlo simulations showed that chance was unlikely to be responsible for ordination patterns, nor for inter-specific variation in passage time and its relationship with species morphology. These data provide annually consistent evidence that migrating sylviid warblers are separated ecologically by habitat use, time of passage and morphology: we cannot refute the hypothesis that community dynamics have influenced niche use and autumn migratory strategy. We call for further tests of the ,migrant interaction' hypothesis in other geographical locations and taxa, particularly where migrants are allopatric and interact ecologically only on migration. [source]

Assessing suicide risk among callers to crisis hotlines: A confirmatory factor analysis,

JOURNAL OF CLINICAL PSYCHOLOGY, Issue 9 2010
Tracy K. Witte
Abstract Our goal was to investigate the factor structure of a risk assessment tool utilized by suicide hotlines and to determine the predictive validity of the obtained factors in predicting subsequent suicidal behavior. We conducted an Exploratory Factor Analysis (EFA), an EFA in a Confirmatory Factor Analysis (EFA/CFA) framework, and a CFA on independent subsamples derived from a total sample of 1,085. Similar to previous studies, we found consistent evidence for a two-factor solution, with one factor representing a more pernicious form of suicide risk (i.e., Resolved Plans and Preparations; RPP) and one factor representing milder suicidal ideation (i.e., Suicidal Desire and Ideation; SDI). The RPP factor trended toward being more predictive of suicidal ideation at follow-up than the SDI factor. © 2010 Wiley Periodicals, Inc. J Clin Psychol 66:1,24, 2010. [source]

Fluctuating asymmetry in a secondary sexual trait: no associations with individual fitness, environmental stress or inbreeding, and no heritability

JOURNAL OF EVOLUTIONARY BIOLOGY, Issue 1 2003
L. E. B. Kruuk
Abstract It has been suggested that fluctuating asymmetry (FA) in secondary sexual traits may be a useful indicator of either individual quality or environmental stress. We tested this concept using a series of analyses of FA in male antler size in a wild red deer (Cervus elaphus) population, using four measures of size repeated across successive years on the same individuals. We found no consistent evidence of correlations between traits in levels of FA, nor of any associations between known environmental or developmental conditions. None of the four measures of FA showed a significant heritability (average h2=0.041), nor was there any evidence of inbreeding depression. For three of the four traits, fluctuating asymmetry did not predict either annual or lifetime breeding success. However there were significant associations between breeding success and FA in antler length. Given the series of null results in our other tests, it seems likely that this was a direct mechanistic effect rather than because measures of FA were indicative of individual quality or condition. [source]

Dispersion patterns of parasites in 0+ year three-spined sticklebacks: a cross population comparison

JOURNAL OF FISH BIOLOGY, Issue 6 2002
M. Kalbe
Two ciliates and 16 metazoan parasites were identified in 434 0+ year three-spined sticklebacks Gasterosteus aculeatus collected from two small rivers and four lakes located in Schleswig-Holstein, Germany. By repeated sampling and analysis of dispersion patterns of six frequently occurring parasites no consistent evidence was found for mortality induced by a single parasite species. Linear log-variance to log-mean abundance ratios with slopes of c. 2 indicated negative binomial distributions for five of the six parasites. The numbers of these six parasites were combined as multiples of S.D. of each parasite species over all samples to form an ,individual parasitation index' (IPI), which showed that only in one locality a slight decrease in parasite burden occurred between September and April. In two of the lake populations, however, there was a distinct decline in the degree of dispersion in spring samples. This indicates that a combination of different species might cause parasite-induced host mortality, undetectable by patterns obtained from single species. There were differences in parasite diversity and intensity of infection among river compared to lake populations suggesting a role for parasites as selective agents in the ecological divergence of three-spined sticklebacks. [source]

Lack of Association of Alcohol Dependence and Habitual Smoking With Catechol-O-methyltransferase

ALCOHOLISM, Issue 11 2007
Tatiana Foroud
Objective:, To test whether variation in the gene encoding the enzyme catechol-O-methyltransferase (COMT), which catalyzes the breakdown of dopamine and other catecholamine neurotransmitters, is associated with the risk for alcohol dependence and habitual smoking. Methods:, Single nucleotide polymophisms (SNPs) were genotyped in a sample of 219 multiplex alcohol-dependent families of European American descent from the Collaborative Study on the Genetics of Alcoholism (COGA). Family-based tests of association were performed to evaluate the evidence of association between the 18 SNPs distributed throughout COMT, including the functional Val158Met polymorphism, and the phenotypes of alcohol dependence, early onset alcohol dependence, habitual smoking, and comorbid alcohol dependence and habitual smoking. Results:, No significant, consistent evidence of association was found with alcohol dependence, early onset alcohol dependence, habitual smoking or the comorbid phenotype. There was no evidence that the functional Val158Met polymorphism, previously reported to be associated with these phenotypes, was associated with any of them. Conclusion:, Despite the substantial size of this study, we did not find evidence to support an association between alcohol dependence or habitual smoking and variation in COMT. [source]

Association Between GABRA1 and Drinking Behaviors in the Collaborative Study on the Genetics of Alcoholism Sample

ALCOHOLISM, Issue 7 2006
Danielle M. Dick
Background: A wealth of literature supports the role of , -aminobutyric acid (GABA) in neurobiological pathways contributing to alcohol dependence and related phenotypes. Animal studies have consistently tied rodent homologs of the GABAA receptor genes on human chromosome 5q to alcohol-related behaviors; however, human studies have produced mixed results. Family-based association analyses previously conducted in the Collaborative Study on the Genetics of Alcoholism (COGA) sample yielded no evidence of association with Diagnostic and Statistical Manual of Mental Disorder,fourth edition (DSM-IV) alcohol dependence and these genes. As a follow-up to that study, we examined several alcohol-related behaviors in the COGA sample as follows: (1) a broader definition of alcohol dependence, including DSM-III-R symptoms and Feighner criteria (referred to as COGA alcohol dependence); (2) withdrawal; (3) history of alcohol-induced blackouts; (4) level of response to alcohol; (5) age of onset of regular drinking; and (6) age at first drunkenness. Methods: Family-based association tests were conducted, using multiple single-nucleotide polymorphisms (SNPs) in each of the 4 GABAA receptor genes on chromosome 5q. Results: In GABRA1, we found evidence of association with several of the drinking behavior phenotypes, including COGA alcohol dependence, history of blackouts, age at first drunkenness, and level of response to alcohol. We did not find consistent evidence of association with the remaining genes and any of the phenotypes. Conclusions: We found evidence for association between GABRA1 and COGA alcohol dependence, history of blackouts, age at first drunkenness, and level of response to alcohol. These analyses suggest that efforts to characterize genetic contributions to alcohol dependence may benefit by examining alcohol-related behaviors in addition to clinical alcohol dependence diagnoses. [source]

Suggestive Linkage on Chromosome 1 for a Quantitative Alcohol-Related Phenotype

ALCOHOLISM, Issue 10 2002
Danielle M. Dick
Background Alcohol dependence is a clinically and etiologically heterogeneous disorder. Accordingly, a variety of subtypes of alcohol-dependent individuals have been proposed, and multiple operational definitions of alcohol use, abuse, and dependence have been used in linkage analyses directed toward detecting genes involved in alcohol use and problems. Here, we develop quantitative phenotypes that characterize drinking patterns among both alcoholic and nonalcoholic subjects, and use these phenotypes in subsequent linkage analyses. Methods More than 9000 individuals from alcoholic and control families were administered a semistructured interview and personality questionnaire as part of the initial stage of the Collaborative Study on the Genetics of Alcoholism (COGA). A principal component analysis was conducted on items that captured many of the dimensions of drinking and related behaviors, including aspects of alcohol use, antisocial behavior and affective disturbance when drinking, and personality. Factor scores were computed for all individuals. Nonparametric linkage analyses were conducted on these factor scores, in the initial COGA sample consisting of 987 individuals from 105 extended families, and in a replication sample consisting of 1295 individuals from 157 extended families. Results Three factors were identified, accounting for 68% of the total variance. The most promising regions of linkage appeared for factor 2, on which higher scores indicate a later age of onset of regular drinking and higher harm avoidance. Chromosome 1 yielded consistent evidence of linkage in both samples, with a maximum lod score of 3.3 when the samples were combined for analysis. Consistent suggestion of linkage also was found to chromosome 15. Conclusions Developing novel phenotypes that more accurately model the effect of influential genes may help efforts to detect genes involved in complex disorders. Applying principal component analysis in the COGA sample provided support for some regions of linkage previously reported in COGA, and identified other new, promising regions of linkage. [source]

Nurse practitioners as an underutilized resource for health reform: Evidence-based demonstrations of cost-effectiveness

JOURNAL OF THE AMERICAN ACADEMY OF NURSE PRACTITIONERS, Issue 4 2010
Jeffrey C. Bauer PhD
Healthcare reform in 2009 was motivated by an imperative to reduce the relentless increase in spending on medical care. Many efforts to solve the problem focused on applying proven principles of evidence-based practice and cost-effectiveness to find the least-expensive way to produce a specific clinical service of acceptable quality. This paper combines economic analysis and reviews published literature to show how the goals of healthcare reform can be accomplished by allowing independently licensed nurse practitioners to provide their wide range of services directly to patients in a variety of clinical settings. The paper presents extensive, consistent evidence that nurse practitioners provide care of equal or better quality at lower cost than comparable services provided by other qualified health professionals. [source]

Is there a role for thyroid hormone on spermatogenesis?

MICROSCOPY RESEARCH AND TECHNIQUE, Issue 11 2009
Marcia Santos Wagner
Abstract Appropriate level of thyroid hormone is essential for normal development and metabolism in most vertebrate tissues and altered thyroid status impacts adversely on them. For many years the testis was regarded as a thyroid hormone unresponsive organ, but consistent evidence accumulated in the past two decades has definitively changed this classical view. Currently, the concept that thyroid hormone plays a critical role in testis development, in rats and other vertebrate species, is clearly established. Although the effects of thyroid hormone on Sertoli and Leydig cells in the immature testis are well described, its role on the adult organ remains controversial. In this review, we summarize and discuss the recent development on the thyroid hormone effects in immature and adult testes. Particularly, we have attempted to address the role of thyroid hormone in the regulation of spermatogenesis, emphasizing recent data that suggest its involvement in germ cells differentiation and survival. Microsc. Res. Tech. 2009. © 2009 Wiley-Liss, Inc. [source]

West Coast study of childhood brain tumours and maternal use of hair-colouring products

PAEDIATRIC & PERINATAL EPIDEMIOLOGY, Issue 3 2002
Elizabeth A Holly
Summary The immature nervous system of the fetus is characterised by rapid cell growth and division and is particularly vulnerable to carcinogens and mutagens. Several epidemiological studies have reported an increased risk for childhood brain tumours (CBT) associated with exposure to N-nitroso compounds (NOC). Hair-colouring products (hair ,dyes') that contain NOC-related aromatic amines have shown mutagenicity in vitro and carcinogenic properties in vivo. The potential public health impact of the relationship between hair dye use and carcinogenesis has prompted epidemiological research, given that a large proportion of American women have used hair dyes. A large population-based case,control study was conducted on the west coast of the USA to investigate risk factors for CBT including exposure to NOC. Eligible CBT patients (<20 years of age and diagnosed between 1984 and 1991) were identified from cancer registries in Los Angeles County, the San Francisco Bay Area in California and the Seattle area in Washington state. A total of 540 biological mothers of these children were interviewed, and 801 control subjects who were frequency matched to the CBT patients on birth year and sex were obtained using random digit dialling. Mothers were asked details about personal use of hair dyes during the index pregnancy including frequency of use, trimester of use and type of dye used. Results from age- and sex-adjusted unconditional logistic regression analyses showed no association between risk for CBT and use of hair dyes 1 month before and/or during pregnancy nor during specific trimesters. A nearly twofold increased risk for CBT was associated with single-interval use during the 1 month before pregnancy, but the confidence interval (CI) was imprecise and the estimate was not different from unity (OR = 1.9, 95% CI [0.5, 7.0]). Exclusive use of permanent dye, temporary dye or hair darkeners was not associated with risk for CBT. A twofold increased risk (OR = 2.0, 95% CI [0.83, 4.7]) was observed with exclusive use of semi-permanent dye during the month before or during pregnancy. Exclusive use of semi-permanent dye during the month before pregnancy and/or first trimester also was associated with an elevated risk for CBT, again not different from unity and with an imprecise CI (OR = 2.5, 95% CI = [0.58, 10.3]). There was no evidence of an association between risk for CBT by histological subtypes and use of hair dyes during the index pregnancy or the month before conception. Together with results from previous studies, these results provide no consistent evidence of an association between risk for CBT and use of hair dyes during pregnancy. [source]

Mechanisms of mutation formation with long-wave ultraviolet light (UVA)

PHOTODERMATOLOGY, PHOTOIMMUNOLOGY & PHOTOMEDICINE, Issue 1 2008
Thomas M. Rünger
Summary Long-wave ultraviolet (UV) A light is able to damage DNA, to cause mutations, and to induce skin cancer, but the exact mechanisms of UVA-induced mutation formation remain a matter of debate. While pyrimidine dimers are well established to mediate mutation formation with shortwave UVB, other types of DNA damage, such as oxidative base damage, have long been thought to be the premutagenic lesions for UVA mutagenesis. However, pyrimidine dimers can also be generated by UVA, and there are several lines of evidence that these are the most important premutagenic lesions not only for UVB- but also for UVA-induced mutation formation. C,T transition mutations, which are generated by pyrimidine dimers, are called UV-signature mutations. They cannot be interpreted to be solely UVB-induced, as they are induced by UVA as well. Furthermore, there is no consistent evidence for a separate UVA-signature mutation that is only generated with UVA. We hypothesize that a weaker anti-mutagenic cellular response, but not a different type of DNA damage, may be responsible for a higher mutation rate per DNA photoproduct with UVA, as compared with UVB. [source]

Optical characterization of Zn0.97Mn0.03Se/ZnSe0.92Te0.08 type II multiple-quantum-well structures

PHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 5 2007
D. Y. Lin
Abstract The optical characterization of type II Zn0.97Mn0.03Se/ZnSe0.92Te0.08 multiple-quantum-well structures have been studied using photoluminescence (PL), temperature-dependent PL, polarized PL, power-dependent PL, and photoreflectance (PR) in this study. The PL data reveal that the band alignment of the ZnMnSe/ZnSeTe system is type II. Comparing with the theoretical calculation based on the Schrodinger equation, the valence band offset is estimated to be 0.6 eV. From the power-dependent PL spectra, it is observed that the peak position of PL spectra shows a blueshift under different excitation power. The blueshift can be interpreted in terms of the band-bending effect due to spatially photoexcited carriers in a type II alignment. The thermal activation energy (EA) for quenching the PL intensity was determined from tem- perature-dependent PL spectra. The thermal activation energy was found to decrease as the thickness of ZnMnSe and ZnSeTe layers decreased. The polarized PL spectra exhibit a large in-plane polarization with the polarization degree up to 50%. The polarization does not depend on the excitation intensity as well as temperature. The large polarization is an inherent orientation of the interface chemical bonds. The higher transition features observed in PR spectra show a blueshift with the similar trend observed in the PL spectra as decreasing the thickness of ZnSeTe layer. This result provides a consistent evidence for the assumption that square-like well shapes were built in the ZnSeTe layers. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

Nitrogen and carbon source,sink relationships in trees at the Himalayan treelines compared with lower elevations

PLANT CELL & ENVIRONMENT, Issue 10 2008
MAI-HE LI
ABSTRACT No single hypothesis or theory has been widely accepted for explaining the functional mechanism of global alpine/arctic treeline formation. The present study tested whether the alpine treeline is determined by (1) the needle nitrogen content associated with photosynthesis (carbon gain); (2) a sufficient source,sink ratio of carbon; or (3) a sufficient C,N ratio. Nitrogen does not limit the growth and development of trees studied at the Himalayan treelines. Levels of non-structural carbohydrates (NSC) in trees were species-specific and site-dependent; therefore, the treeline cases studied did not show consistent evidence of source/carbon limitation or sink/growth limitation in treeline trees. However, results of the combined three treelines showed that the treeline trees may suffer from a winter carbon shortage. The source capacity and the sink capacity of a tree influence its tissue NSC concentrations and the carbon balance; therefore, we suggest that the persistence and development of treeline trees in a harsh alpine environment may require a minimum level of the total NSC concentration, a sufficiently high sugar:starch ratio, and a balanced carbon source,sink relationship. [source]

Cellular patterns in the inner retina of adult zebrafish: Quantitative analyses and a computational model of their formation

THE JOURNAL OF COMPARATIVE NEUROLOGY, Issue 1 2004
David A. Cameron
Abstract The mechanisms that control cellular pattern formation in the growing vertebrate central nervous system are poorly understood. In an effort to reveal mechanistic rules of cellular pattern formation in the central nervous system, quantitative spatial analysis and computational modeling techniques were applied to cellular patterns in the inner retina of the adult zebrafish. All the analyzed cell types were arrayed in nonrandom patterns tending toward regularity; specifically, they were locally anticlustered. Over relatively large spatial scales, only one cell type exhibited consistent evidence for pattern regularity, suggesting that cellular pattern formation in the inner retina is dominated by local anticlustering mechanisms. Cross-correlation analyses revealed independence between the patterns of different cell types, suggesting that cellular pattern formation may involve multiple, independent, homotypic anticlustering mechanisms. A computational model of cellular pattern formation in the growing zebrafish retina was developed, which featured an inhibitory, homotypic signaling mechanism, arising from differentiated cells, that controlled the spatial profile of cell fate decisions. By adjusting the spatial profile of this decaying-exponential signal, the model provided good estimates of all the cellular patterns that were observed in vivo, as objectively judged by quantitative spatial pattern analyses. The results support the hypothesis that cellular pattern formation in the inner retina of zebrafish is dominated by a set of anticlustering mechanisms that may control events at, or near, the spatiotemporal point of cell fate decision. J. Comp. Neurol. 471:11,25, 2004. © 2004 Wiley-Liss, Inc. [source]

Volunteering and health among older people: a review

AUSTRALASIAN JOURNAL ON AGEING, Issue 2 2003
Jenny Onyx
This paper presents a review of the available literature on the relationship between volunteering and health among older people. There is consistent evidence that morbidity rates, functional health indices, self reported health and life satisfaction are affected by formal and informal volunteering. Some studies suggest that the benefits of volunteering are reciprocal, in that both those who give and those who receive assistance benefit. The evidence is consistent with the proposal that social capital is generated through volunteering. It is likely that the presence of high levels of social capital supports and maintains the health of older persons, provides informal support in times of sickness and stress and thus enhances quality of life as well as reducing or delaying the onset of illness and death. [source]