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Decision-making deficits, assessed cognitively, are often associated with mental health symptoms, however, this relationship is not fully understood. This paper explores the relationship between mental health disorders and decision-making, using the Cambridge Gambling Task (CGT). Our study investigated how decision-making varied across 20 different mental health conditions compared to controls in a sample of 572 young adults from the Minneapolis and Chicago metropolitan areas, using a computerized laboratory-based task. Almost all mental health conditions were associated with at least mild (i.e. at least small effect size) impairment in all three studied parameters of the CGT (risk adjustment, quality of decision-making and overall proportion of bet). Notably, binge eating disorder had the largest cognitive impairment and gambling disorder had moderate impairment. Post-traumatic stress disorder (PTSD) was associated with impaired decision-making while obsessive-compulsive disorder (OCD) and depression showed moderate impairment. Additionally, half of the disorders assessed had moderate to large impairment in risk adjustment.These findings suggest that mental health conditions may have a more complex cognitive profile than previously thought, and a better understanding of these impairments may aid in risk assessment and targeted clinical interventions. This study underscores the need for further research to determine the causal pathways between mental health conditions and cognition, as well as to better understand the day-to-day impact of such deficits.
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BACKGROUND: Symptoms of attention deficit hyperactivity disorder (ADHD) and trait impulsivity have been associated with disordered eating but are seldom assessed in community studies, or longitudinally and little is known about the mediating mechanisms. METHODS: We tested associations between ADHD symptoms and disordered eating cross-sectionally and between trait impulsivity and disordered eating longitudinally. We utilised data from a normative cohort of young adults (642 participants: 65% female, Mage = 23 years). Participants were classified as high risk or low risk for disordered eating using the SCOFF instrument. In the first two steps of both cross-sectional and longitudinal hierarchical logistic regression models, demographics and covariates were entered. For the cross-sectional regression, Adult ADHD self-report scale (ASRS) scores, separated into inattentive and hyperactive/impulsive symptoms, were entered in the third step. In a separate longitudinal model, Barratt impulsivity scale subscales (attentional, motor and non-planning impulsivity) were entered in the third step. Depression, as assessed by the moods and feelings questionnaire (MFQ), was examined as a mediator. RESULTS: Cross-sectionally, sex, MFQ score and inattentive symptoms predicted disordered eating risk (model R2 = 20%). Longitudinally, sex, MFQ score and attentional impulsivity predicted disordered eating risk (model R2 = 16%). The relationship between inattentive symptoms and the disordered eating risk was partially mediated by MFQ score, whereas the relationship between attentional impulsivity and the disordered eating risk was fully mediated by MFQ scores. CONCLUSIONS: These data highlight (1) a specific role for inattentive symptoms of ADHD and (2) the importance of both depression and impulsivity in predicting eating disorder risk.
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Transtorno do Deficit de Atenção com Hiperatividade , Transtornos da Alimentação e da Ingestão de Alimentos , Humanos , Feminino , Adulto Jovem , Adulto , Masculino , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Estudos Transversais , Comportamento Impulsivo , Inquéritos e QuestionáriosRESUMO
BACKGROUND: The concepts of impulsivity and compulsivity are commonly used in psychiatry. Little is known about whether different manifest measures of impulsivity and compulsivity (behavior, personality, and cognition) map onto underlying latent traits; and if so, their inter-relationship. METHODS: A total of 576 adults were recruited using media advertisements. Psychopathological, personality, and cognitive measures of impulsivity and compulsivity were completed. Confirmatory factor analysis was used to identify the optimal model. RESULTS: The data were best explained by a two-factor model, corresponding to latent traits of impulsivity and compulsivity, respectively, which were positively correlated with each other. This model was statistically superior to the alternative models of their being one underlying factor ('disinhibition') or two anticorrelated factors. Higher scores on the impulsive and compulsive latent factors were each significantly associated with worse quality of life (both p < 0.0001). CONCLUSIONS: This study supports the existence of latent functionally impairing dimensional forms of impulsivity and compulsivity, which are positively correlated. Future work should examine the neurobiological and neurochemical underpinnings of these latent traits; and explore whether they can be used as candidate treatment targets. The findings have implications for diagnostic classification systems, suggesting that combining categorical and dimensional approaches may be valuable and clinically relevant.
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Comportamento Compulsivo/fisiopatologia , Comportamento Impulsivo/fisiologia , Transtornos Mentais/fisiopatologia , Personalidade/fisiologia , Adolescente , Adulto , Comportamento Compulsivo/classificação , Análise Fatorial , Feminino , Humanos , Comportamento Impulsivo/classificação , Masculino , Transtornos Mentais/classificação , Modelos Estatísticos , Personalidade/classificação , Psiquiatria/métodos , Adulto JovemRESUMO
OBJECTIVE: Research on health correlates in gamblers has found an association between gambling and obesity. The neurocognitive underpinnings of impulsivity may be useful targets for understanding and ultimately treating individuals with both gambling and obesity problems. METHOD: 207 non-treatment seeking young adults (18-29 years) with subsyndromal gambling disorder were recruited from the community. Subjects were grouped according to weight ('normal weight' BMI<25, 'overweight' BMI≥25; or 'obese' BMI≥30). Measures relating to gambling behaviour and objective computerized neurocognitive measures were collected. RESULTS: Of the 207 subjects, 22 (10.6%) were obese and 49 (23.7%) were overweight. The obese gamblers consumed more nicotine (packs per day equivalent) and reported losing more money per week to gambling. Obese gamblers exhibited significant impairments in terms of reaction times for go trials on the stop-signal test (SST), quality of decision making and risk adjustment on the Cambridge Gamble Test (CGT), and sustained attention on the rapid visual information processing task (RVP). CONCLUSION: Obesity was associated with decision making and sustained attention impairments in gamblers, along with greater monetary loss due to gambling. Future work should use longitudinal designs to examine the temporal relationship between these deficits, weight, other impulsive behaviour, and functional impairment.
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Tomada de Decisões , Jogo de Azar , Obesidade , Tempo de Reação , Assunção de Riscos , Adulto , Atenção , Índice de Massa Corporal , Feminino , Jogo de Azar/diagnóstico , Jogo de Azar/fisiopatologia , Jogo de Azar/psicologia , Humanos , Comportamento Impulsivo , Masculino , Testes Neuropsicológicos , Obesidade/diagnóstico , Obesidade/fisiopatologia , Obesidade/psicologia , Escalas de Graduação Psiquiátrica , Estatística como Assunto , Análise e Desempenho de TarefasRESUMO
The opioid system is implicated in the hedonic and motivational processing of food, and in binge eating, a behaviour strongly linked to obesity. The aim of this study was to evaluate the effects of 4 weeks of treatment with the mu-opioid receptor antagonist GSK1521498 on eating behaviour in binge-eating obese subjects. Adults with body mass index ≥ 30 kg m(-2) and binge eating scale scores ≥ 19 received 1-week single-blind placebo run-in, and were then randomized to 28 days with either 2 mg day(-1) GSK1521498, 5 mg day(-1) GSK1521498 or placebo (N=21 per arm) in a double-blind parallel group design. The outcome measures were body weight, fat mass, hedonic and consummatory eating behaviour during inpatient food challenges, safety and pharmacokinetics. The primary analysis was the comparison of change scores in the higher-dose treatment group versus placebo using analysis of covariance at each relevant time point. GSK1521498 (2 mg and 5 mg) was not different from placebo in its effects on weight, fat mass and binge eating scores. However, compared with placebo, GSK1521498 5 mg day(-1) caused a significant reduction in hedonic responses to sweetened dairy products and reduced calorific intake, particularly of high-fat foods during ad libitum buffet meals, with some of these effects correlating with systemic exposure of GSK1521498. There were no significant effects of GSK1521498 2 mg day(-1) on eating behaviour, indicating dose dependency of pharmacodynamics. GSK1521498 was generally well tolerated and no previously unidentified safety signals were detected. The potential for these findings to translate into clinically significant effects in the context of binge eating and weight regain prevention requires further investigation.
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Bulimia/tratamento farmacológico , Comportamento Alimentar/efeitos dos fármacos , Indanos/farmacologia , Receptores Opioides mu/antagonistas & inibidores , Triazóis/farmacologia , Adolescente , Adulto , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Indanos/administração & dosagem , Indanos/uso terapêutico , Masculino , Pessoa de Meia-Idade , Triazóis/administração & dosagem , Triazóis/uso terapêutico , Adulto JovemRESUMO
The STM7 gene on chromosome 9 was recently 'excluded' as a candidate for Friedreich's ataxia following the identification of an expanded intronic GAA triplet repeat in the adjacent gene, X25, in patients with the disease. Using RT-PCR, northern and sequence analyses, we now demonstrate that X25 comprises part of the STM7 gene, contributing to at least four splice variants, and report the identification of new coding sequences. Functional analysis of the STM7 recombinant protein corresponding to the reported 2.7-kilobase transcript has demonstrated PtdlnsP 5-kinase activity, supporting the idea that the disease is caused by a defect in the phosphoinositide pathway, possibly affecting vesicular trafficking or synaptic transmission.
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Ataxia de Friedreich/genética , Genes/genética , Proteínas de Ligação ao Ferro , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Proteínas/genética , Adulto , Processamento Alternativo/genética , Sequência de Aminoácidos , Mapeamento Cromossômico , Éxons/genética , Ataxia de Friedreich/enzimologia , Humanos , Dados de Sequência Molecular , Especificidade de Órgãos , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Placenta , RNA Mensageiro/análise , RNA Mensageiro/genética , Proteínas Recombinantes de Fusão/metabolismo , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , FrataxinaRESUMO
BACKGROUND: Impairments in working memory are present in many psychiatric illnesses such as attention-deficit hyperactivity disorder (ADHD) and schizophrenia. The dopamine transporter and catechol-O-methyltransferase (COMT) are proteins involved in dopamine clearance and the dopamine system is implicated in the modulation of working memory (WM) processes and neurochemical models of psychiatric diseases. The effects of functional polymorphisms of the dopamine transporter gene (DAT1) and the COMT gene were investigated using a visuospatial and numerical n-back working memory paradigm. Our n-back task was designed to reflect WM alone, and made no demands on higher executive functioning. METHOD: A total of 291 healthy volunteers (aged 18-45 years) were genotyped and matched for age, sex, and Barratt Impulsivity Scale (BIS) and National Adult Reading Test (NART) scores. To assess individual gene effects on WM, factorial mixed model analysis of variances (ANOVAs) were conducted with the between-subjects factor as genotype and difficulty level (0-, 1-, 2- and 3-back) entered as the within-subjects factor. RESULTS: The analysis revealed that the DAT1 or COMT genotype alone or in combination did not predict performance on the n-back task in our sample of healthy volunteers. CONCLUSIONS: Behavioral effects of DAT1 and COMT polymorphisms on WM in healthy volunteers may be non-existent, or too subtle to identify without exceedingly large sample sizes. It is proposed that neuroimaging may provide more powerful means of elucidating the modulatory influences of these polymorphisms.
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Catecol O-Metiltransferase/genética , Proteínas da Membrana Plasmática de Transporte de Dopamina/genética , Memória de Curto Prazo , Adolescente , Adulto , Catecol O-Metiltransferase/fisiologia , Proteínas da Membrana Plasmática de Transporte de Dopamina/fisiologia , Feminino , Estudos de Associação Genética , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Reação em Cadeia da Polimerase , Polimorfismo Genético , Adulto JovemRESUMO
BACKGROUND: As a behavioral addiction with clinical and phenomenological similarities to substance addiction, recreational and pathological gambling represent models for studying the neurobiology of addiction, without the confounding deleterious brain effects which may occur from chronic substance abuse. METHOD: A community sample of individuals aged 18-65 years who gamble was solicited through newspaper advertising. Subjects were grouped a priori into three groups (no-risk, at-risk, and pathological gamblers) based on a diagnostic interview. All subjects underwent a psychiatric clinical interview and neurocognitive tests assessing motor impulsivity and cognitive flexibility. Subjects with a current axis I disorder, history of brain injury/trauma, or implementation or dose changes of psychoactive medication within 6 weeks of study enrollment were excluded. RESULTS: A total of 135 no-risk, 69 at-risk and 46 pathological gambling subjects were assessed. Pathological gamblers were significantly older, and exhibited significant deficiencies in motor impulse control (stop-signal reaction times), response speed (median 'go' trial response latency) and cognitive flexibility [total intra-dimensional/extra-dimensional (IDED) errors] versus controls. The finding of impaired impulse control and cognitive flexibility was robust in an age-matched subgroup analysis of pathological gamblers. The no-risk and at-risk gambling groups did not significantly differ from each other on task performance. CONCLUSIONS: Impaired response inhibition and cognitive flexibility exist in people with pathological gambling compared with no-risk and at-risk gamblers. The early identification of such illness in adolescence or young adulthood may aid in the prevention of addiction onset of such disabling disorders.
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Comportamento Aditivo/psicologia , Jogo de Azar/epidemiologia , Jogo de Azar/psicologia , Adolescente , Adulto , Idoso , Análise de Variância , Comportamento Aditivo/diagnóstico , Comportamento Aditivo/epidemiologia , Cognição , Feminino , Jogo de Azar/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Tempo de Reação , Fatores de Risco , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Transtornos Relacionados ao Uso de Substâncias/psicologia , Adulto JovemRESUMO
Competency-based medical education (CBME) curricula are becoming increasingly common in graduate medical education. Put simply, CBME is focused on educational outcomes, is independent of methods and time, and is composed of achievable competencies.1 In spite of widespread uptake, there remains much to learn about implementing CBME at the program level. Leveraging the collective experience of program leaders at Queen's University, where CBME simultaneously launched across 29 specialty programs in 2017, this paper leverages change management theory to provide a short summary of how program leaders can navigate the successful preparation, launch, and initial implementation of CBME within their residency programs.
Les programmes de formation médicale fondée sur les compétences (FMFC) sont de plus en plus répandus dans les études supérieures en médecine. En termes simples, la FMFC est centrée sur les résultats scolaires, elle est indépendante des méthodes et du temps, et est constituée de compétences réalisables.1 Malgré cette adoption généralisée, il reste encore beaucoup à apprendre sur la mise en Åuvre de la FMFC au niveau des programmes. Tirant profit de l'expérience collective des responsables de programmes à l'Université Queen, où la FMFC a été lancée simultanément dans 29 programmes de spécialité en 2017,le présent article s'appuie sur la théorie de la gestion du changement pour produire un court résumé de la manière dont les responsables de programmes peuvent gérer avec succès la préparation, le lancement et la mise en Åuvre initiale de la FMFC au sein de leurs programmes de résidence.
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Photosensitive membrane structures in the retinular cells of the Limulus lateral eye are broken down and renewed daily. The first light onset causes a rapid, synchronous disassembly and buildup of the rhabdom in each photoreceptor cell. The entire process is complete within 30 minutes. Blocking the efferent input to the retina from the brain blocks the turnover of the rhabdom, and mimicking the efferent input by optic nerve stimulation restores it.
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Caranguejos Ferradura/fisiologia , Luz , Células Fotorreceptoras/fisiologia , Animais , Vias Eferentes/fisiologia , Estimulação Elétrica , Nervo Óptico/fisiologia , Células Fotorreceptoras/citologia , Regeneração , Retina/citologia , Retina/fisiologia , Fatores de TempoRESUMO
At night efferent optic nerve activity generated by a circadian clock in the Limulus brain changes the structure of the photoreceptor and surrounding pigment cells in the animal's lateral eyes. The structural changes allow each ommatidium to gather light from a wider area at night than during the day. Visual sensitivity is thereby increased, but spatial resolution is diminished. At daybreak efferent activity from the clock stops, the structural changes reverse, and the field of view of each ommatidium decreases. The cyclic changes are endogenous and continue in the dark. Thus, under the control of a circadian clock, the Limulus eye exchanges its daytime acuity for greater sensitivity at night.
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Caranguejos Ferradura/fisiologia , Potenciais de Ação , Vias Aferentes , Animais , Encéfalo/fisiologia , Ritmo Circadiano , Vias Eferentes , Olho/anatomia & histologia , Fenômenos Fisiológicos Oculares , Nervo Óptico/fisiologia , Células Fotorreceptoras/fisiologiaRESUMO
Octopamine synthesized in vitro from tyramine by Limulus lateral and ventral eyes was located by light microscopic and electron microscopic autoradiography in efferent fibers which innervate ventral photoreceptors and lateral eye ommatidia. Newly synthesized octopamine was released from efferent fibers in response to depolarization in high concentrations of potassium. We propose that octopamine is a neurotransmitter of efferent fibers that may modulate basic retinal processes such as photoreceptor sensitivity, photomechanical movements, and photoreceptive membrane turnover.
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Caranguejos Ferradura/metabolismo , Octopamina/biossíntese , Animais , Vias Eferentes/metabolismo , Caranguejos Ferradura/anatomia & histologia , Neurotransmissores/metabolismo , Octopamina/metabolismo , Células Fotorreceptoras/metabolismo , Potássio/farmacologia , Taxa Secretória/efeitos dos fármacos , Vias Visuais/metabolismoRESUMO
Mutations in the human APC gene are linked to familial adenomatous polyposis and to the progression of sporadic colorectal and gastric tumors. To gain insight into APC function, APC-associated proteins were identified by immunoprecipitation experiments. Antibodies to APC precipitated a 95-kilodalton protein that was purified and identified by sequencing as beta-catenin, a protein that binds to the cell adhesion molecule E-cadherin. An antibody specific to beta-catenin also recognized the 95-kilodalton protein in the immunoprecipitates. These results suggest that APC is involved in cell adhesion.
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Caderinas/metabolismo , Neoplasias do Colo/metabolismo , Proteínas do Citoesqueleto/metabolismo , Genes APC , Proteínas de Neoplasias/metabolismo , Transativadores , Proteína da Polipose Adenomatosa do Colo , Sequência de Aminoácidos , Anticorpos , Adesão Celular , Linhagem Celular , Neoplasias do Colo/genética , Proteínas do Citoesqueleto/química , Proteínas do Citoesqueleto/isolamento & purificação , Humanos , Dados de Sequência Molecular , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/imunologia , Testes de Precipitina , Células Tumorais Cultivadas , beta CateninaRESUMO
OBJECTIVES: To assess the ability of the new software SonoAVC to measure follicular volume and to compare these volume calculations with those made by conventional methods. METHODS: Three-dimensional ultrasound imaging was used to acquire volumetric data from the ovaries of 51 women undergoing controlled ovarian stimulation as part of in-vitro fertilization treatment. All assessments were performed on the day of oocyte retrieval and the true volume of each follicle was ascertained by manual measurement of the follicular aspirate. SonoAVC was used to automatically measure the volume of follicles and to provide three perpendicular diameters (xyz diameters), which were used to estimate volume using the sphere formula. The sphere formula was also used to estimate the volume from manual measurements of follicle diameter derived from conventional two-dimensional (2D) displays. Virtual Organ Computer-aided AnaLysis (VOCAL) was also used to measure volume, and the validity of each technique was compared using limits of agreement. RESULTS: Two hundred and twenty-four follicles with a mean follicular volume of 3.7 (range, 0.4-16.2) cm(3) were studied. SonoAVC provided highly accurate automatic follicular volume measurements in all cases. Volume estimations made from the automatic maximal follicular diameter measurements (xyz diameters) were less valid. VOCAL proved highly valid but was less accurate than SonoAVC. Volumes estimated from manually derived follicular diameter measurements were the least accurate. CONCLUSIONS: SonoAVC provides highly valid, automatic measurements of follicular volume. These measurements are more accurate than volumes estimated from 2D manual measurements, automated measurements of follicular diameter and those calculated using VOCAL.
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Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Folículo Ovariano/diagnóstico por imagem , Software , Adulto , Processamento Eletrônico de Dados/métodos , Feminino , Fertilização in vitro , Líquido Folicular , Humanos , Ovário/diagnóstico por imagem , Indução da Ovulação , UltrassonografiaRESUMO
A central focus of pollination biology is to document the relative effectiveness of different flower visitors as pollinators. Ongoing research seeks to determine the role that introduced honey bees (Apis mellifera L.) play in the pollination of both invasive and native plants. Here we report on the importance of A. mellifera as pollinators of a California native plant, Triteleia laxa Bentham. In observation plots and transect censuses, A. mellifera overwhelmingly dominated the T. laxa flower visitor assemblage. We believe the proximity to agriculture, where A. mellifera density is higher relative to areas far from agriculture, contributes to the discrepancy between A. mellifera abundance at the two sites. Although A. mellifera were inferior flower visitors qualitatively (visited less flowers per minute), they were the most frequent interactors with flowers. Furthermore, the proportion of visits to flowers on the same plant among flower visitor species did not differ, suggesting a general mechanism by which insects forage at T. laxa flowers and that A. mellifera do not cause more deleterious geitonogamy than do native pollinators. Flower visitation rates as a function of floral display size did not differ between A. mellifera and other flower visitors. The difference in the magnitude of flower visitation (largely by A. mellifera) between sites is consistent with a difference in seed set between sites. These results suggest that non-native A. mellifera bees can play an important role in the pollination of native plant species.
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Abelhas , Comportamento Animal , Flores/fisiologia , Liliaceae/fisiologia , Polinização , Animais , California , Dípteros , Ecossistema , Lepidópteros , Sementes/crescimento & desenvolvimento , Fatores de TempoRESUMO
The Internet is now all-pervasive across much of the globe. While it has positive uses (e.g. prompt access to information, rapid news dissemination), many individuals develop Problematic Use of the Internet (PUI), an umbrella term incorporating a range of repetitive impairing behaviours. The Internet can act as a conduit for, and may contribute to, functionally impairing behaviours including excessive and compulsive video gaming, compulsive sexual behaviour, buying, gambling, streaming or social networks use. There is growing public and National health authority concern about the health and societal costs of PUI across the lifespan. Gaming Disorder is being considered for inclusion as a mental disorder in diagnostic classification systems, and was listed in the ICD-11 version released for consideration by Member States (http://www.who.int/classifications/icd/revision/timeline/en/). More research is needed into disorder definitions, validation of clinical tools, prevalence, clinical parameters, brain-based biology, socio-health-economic impact, and empirically validated intervention and policy approaches. Potential cultural differences in the magnitudes and natures of types and patterns of PUI need to be better understood, to inform optimal health policy and service development. To this end, the EU under Horizon 2020 has launched a new four-year European Cooperation in Science and Technology (COST) Action Programme (CA 16207), bringing together scientists and clinicians from across the fields of impulsive, compulsive, and addictive disorders, to advance networked interdisciplinary research into PUI across Europe and beyond, ultimately seeking to inform regulatory policies and clinical practice. This paper describes nine critical and achievable research priorities identified by the Network, needed in order to advance understanding of PUI, with a view towards identifying vulnerable individuals for early intervention. The network shall enable collaborative research networks, shared multinational databases, multicentre studies and joint publications.
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Comportamento Aditivo , Comportamento Compulsivo , Internacionalidade , Internet , Pesquisa , Europa (Continente) , HumanosRESUMO
BACKGROUND AND STUDY AIMS: Hereditary hemorrhagic telangiectasia (HHT) is a rare autosomal dominant disorder characterized by telangiectasia formation that can lead to small-bowel bleeding. In this study, video capsule endoscopy was used to compare the small-bowel findings observed in patients with HHT with those seen in patients without the condition. PATIENTS AND METHODS: We performed capsule endoscopy studies in 93 consecutive patients who were being evaluated for small-bowel bleeding, 38 patients with known or suspected HHT and 55 patients without HHT. Nine patients were excluded because the capsule failed to reach the cecum. The findings in 32 patients with a final diagnosis of HHT and in 48 patients without HHT were recorded and compared. RESULTS: Capsule endoscopy detected telangiectases evenly distributed throughout the small bowel in 26/32 (81%) patients with HHT, compared with 14/48 (29%) in patients without HHT. When active bleeding was observed in patients with HHT (n = 4), the bleeding was within reach of standard small-bowel push enteroscopy in all cases. The presence of five or more gastrointestinal telangiectases by capsule endoscopy had a sensitivity of 75% and a positive predictive value of 86% for diagnosing HHT. Unexpected findings (small-bowel polyps and mass-like lesions) were seen in both groups of patients (6.2% in patients with HHT and 2.1% in patients without HHT). CONCLUSIONS: Small-bowel telangiectases were seen in the majority of patients with HHT and were evenly distributed throughout the small bowel. Telangiectases were observed in only a minority of patients who did not have HHT. Actively bleeding small-bowel telangiectases were located in the proximal and mid-small bowel in patients with HHT, all within reach of an enteroscope. We propose a cutoff point of at least five gastrointestinal telangiectases to support a diagnosis of HHT.
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Endoscopia por Cápsula , Hemorragia Gastrointestinal/diagnóstico , Enteropatias/diagnóstico , Telangiectasia Hemorrágica Hereditária/diagnóstico , Adulto , Idoso , Feminino , Humanos , Intestino Delgado , Masculino , Pessoa de Meia-Idade , Estudos ProspectivosRESUMO
The use of models by ecologists and environmental managers, to inform environmental management and decision-making, has grown exponentially in the past 50 years. Due to logistical, economical, and theoretical benefits, model users frequently transfer preexisting models to new sites where data are scarce. Modelers have made significant progress in understanding how to improve model generalizability during model development. However, models are always imperfect representations of systems and are constrained by the contextual frameworks used during their development. Thus, model users need better ways to evaluate the possibility of unintentional misapplication when transferring models to new sites. We propose a method of describing a model's application niche for use during the model selection process. Using this method, model users synthesize information from databases, past studies, and/or past model transfers to create model performance curves and heat maps. We demonstrated this method using an empirical model developed to predict the ecological condition of plant communities in riverine wetlands of the Appalachian Highland physiographic region, U.S.A. We assessed this model's transferability and generalizability across (1) riverine wetlands in the contiguous U.S.A., (2) wetland types in the Appalachian Highland physiographic region, and (3) wetland types in the contiguous U.S.A. With this methodology and a discussion of its critical steps, we set the stage for further inquiries into the development of consistent and transparent practices for model selection when transferring a model.
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Following active service during the 1990/1991 Gulf conflict, a number of UK and US veterans presented with a diverse range of symptoms, collectively known as Gulf Veterans' Illnesses (GVI). The administration of vaccines and/or the pretreatment against possible nerve agent poisoning, pyridostigmine bromide (PB), given to Armed Forces personnel during the Gulf conflict has been implicated as a possible factor in the aetiology of these illnesses. The possibility that long-term health effects may result from the administration of these vaccines (anthrax, pertussis, plague, yellow fever, polio, typhoid, tetanus, hepatitis B, meningococcal meningitis and cholera) and/or PB, have been investigated using a non-human primate model, the common marmoset. This paper reports the results from two aspects of the study, brain electrical activity (EEG, collected during performance of a touchscreen mediated discrimination task) and sleep. There were no marked long-term changes in EEG or sleep patterns that could be attributed to vaccines and/or PB administration. The changes that were detected were predominantly time related and independent of treatment. Where statistical differences were detected between treatments, the magnitudes of the difference were relatively minor and therefore not regarded as having long term biological significance.