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1.
Artif Organs ; 44(6): 584-593, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31912510

RESUMO

With the incidence of end-stage heart failure steadily increasing, the need for a practical total artificial heart (TAH) has never been greater. Continuous flow TAHs (CFTAH) are being developed using rotary blood pumps (RBPs), leveraging their small size, mechanical simplicity, and excellent durability. To completely replace the heart with currently available RBPs, two are required; one for providing pulmonary flow and one for providing systemic flow. To prevent hazardous states, it is essential to maintain balance between the pulmonary and systemic circulation at a wide variety of physiologic states. In this study, we investigated factors determining a CFTAH's inherent ability to balance systemic and pulmonary flow passively, without active management of pump rotational speed. Four different RBPs (ReliantHeart HA5, Thoratec HMII, HeartWare HVAD, and Ventracor VentrAssist) were used in various combinations to construct CFTAHs. Each CFTAH's ability to autonomously maintain pressures and flows within defined ranges was evaluated in a hybrid mock loop as systemic and pulmonary vascular resistance (PVR) were changed. The resistance box, a method to quantify the range of vascular resistances that can be safely supported by a CFTAH, was used to compare different CFTAH configurations in an efficient and predictive way. To reduce the need for future in vitro tests and to aid in their analysis, a novel analytical evaluation to predict the resistance box of various CFTAH configurations was also performed. None of the investigated CFTAH configurations fully satisfied the predefined benchmarks for inherent flow balancing, with the VentrAssist (left) and HeartAssist 5 (right) offering the best combination. The extent to which each CFTAH was able to autonomously maintain balance was determined by the pressure sensitivity of each RPB: the sensitivity of outflow to changes in the pressure head. The analytical model showed that by matching left and right pressure sensitivity the inherent balancing performance can be improved. These findings may ultimately lead to a reduced need for manual speed changes or active control systems.

2.
Personal Disord ; 11(2): 131-140, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31621364

RESUMO

Borderline personality disorder (BPD) involves instability in self-concept, emotions, and behavior. However, the dynamic, longitudinal relations among BPD symptoms and between these symptoms and other problematic emotional experiences are poorly understood. It is also unclear whether these dynamics are the same across persons (including across diagnostic boundaries), specific to individuals with BPD, or idiographic. The current study uses ecological momentary assessment and group iterative multiple model estimation, a novel, data-driven approach to identifying dynamic patterns in time-series data at group, subgroup, and individual levels, to investigate the dynamic connections among select features of BPD (anger, impulsivity, and identity disturbance) and anxiety-related experiences. Forty-two psychiatric outpatients diagnosed with BPD (n = 27) or with an anxiety disorder, but not BPD (n = 15), rated their anger, identity disturbance, impulsivity, anxiety, stress, and calmness states 6 times per day for 21 days, providing a total of 4,699 surveys. Only 1 dynamic link between symptoms was identified that applied at the group level, and group iterative multiple model estimation did not reveal stable subgroups of individuals with distinct symptom dynamics. Instead, these dynamics differed from individual to individual. These results suggest that connections among these BPD and anxiety symptoms do not depend on diagnosis and are somewhat idiographic. Case examples are used to illustrate the clinical utility of within-person symptom models as a supplement to traditional diagnostic information. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

3.
Clin Anat ; 2019 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-31301249

RESUMO

Intra-articular hip joint pathology is a source of hip and groin pain in active individuals and is thought to be a precursor to hip osteoarthritis. Limited evidence exists to guide appropriate physiotherapy management for these patients. Identification of which hip muscles are affected may help clinicians to develop effective exercise programs. A cross-sectional observational study in a hospital setting was conducted to investigate the size of individual hip abductor, hip extensor, and hip external rotator muscles in patients with acetabular labral joint pathology compared with age and sex matched healthy subjects. Twelve participants (eight females, four males), aged 20-53 years, with a medical diagnosis of unilateral acetabular labral tear and 12 healthy participants were recruited. Magnetic resonance imaging was used to assess cross-sectional areas of the gluteus minimus, gluteus medius, upper gluteus maximus, lower gluteus maximus, piriformis, and quadratus femoris muscles bilaterally. Gluteus medius muscle cross-sectional area was significantly different between groups (P < 0.01, effect size = 0.92) with muscle size found to be smaller in the pathology group. No differences were found for the other hip muscles (P > 0.05). These findings suggest that hip muscles are not all affected equally by the presence of intra-articular hip joint pathology. Atrophy of specific hip muscles, which are important in hip joint and pelvic stability, may alter hip joint function during gait and functional tasks. Clinicians treating patients with intra-articular hip joint pathology may need to prescribe exercises targeting the specific muscles with demonstrated dysfunction. Clin. Anat., 2019. © 2019 Wiley Periodicals, Inc.

4.
PLoS One ; 14(7): e0220300, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31344110

RESUMO

BACKGROUND: The capability of electronic cigarette devices (e-cigs) to deliver nicotine is key to their potential to replace combustible cigarettes. We compared nicotine delivery and subjective effects associated with the use of two classes of e-cigarettes and cigarettes. METHODS: 14 e-cigarette users were instructed to vape their own e-cigarette device every 20 seconds for 10 minutes while blood was drawn at 1, 2, 4, 6, 8, 10,12, and 15 minutes after initiating vaping. Users rated withdrawal symptoms and side effects before and after vaping. E-cigarette devices were classified as first-generation (same size as cigarette, no activation button) or advanced (larger than cigarette with an activation button). Separately, 10 cigarette smokers completed a similar protocol. Fisher's Exact Test and two-sided t-tests were used as appropriate to determine differences in outcomes between first-generation e-cigarette users, advanced e-cigarette users, and smokers. RESULTS: Compared to first-generation devices, advanced devices were associated with greater serum nicotine Cmax (ng/ml) (11.5 v. 2.8, p = 0.0231) and greater nicotine boost (ng/ml) (10.8 v. 1.8, p = 0.0177). Overall, e-cigarettes users experienced a significant reduction in withdrawal and craving, although there were no significant differences between users of first-generation and advanced devices. Comparing e-cigarettes overall to cigarettes, cigarettes were associated with greater Cmax (25.9 v. 9.0, p = 0.0043) and greater nicotine boost (21.0 v. 8.2, p = 0.0128). CONCLUSIONS: Advanced e-cigarettes delivered significantly more nicotine than first-generation devices but less than combustible cigarettes. Overall, e-cigarette use was associated with a reduction in withdrawal and craving with no reported side effects. The wide variation in nicotine absorption from different e-cigarette devices should be considered in studies of e-cigarettes for smoking cessation.

5.
Hum Mutat ; 40(9): 1330-1345, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31144778

RESUMO

The Critical Assessment of Genome Interpretation-5 intellectual disability challenge asked to use computational methods to predict patient clinical phenotypes and the causal variant(s) based on an analysis of their gene panel sequence data. Sequence data for 74 genes associated with intellectual disability (ID) and/or autism spectrum disorders (ASD) from a cohort of 150 patients with a range of neurodevelopmental manifestations (i.e. ID, autism, epilepsy, microcephaly, macrocephaly, hypotonia, ataxia) have been made available for this challenge. For each patient, predictors had to report the causative variants and which of the seven phenotypes were present. Since neurodevelopmental disorders are characterized by strong comorbidity, tested individuals often present more than one pathological condition. Considering the overall clinical manifestation of each patient, the correct phenotype has been predicted by at least one group for 93 individuals (62%). ID and ASD were the best predicted among the seven phenotypic traits. Also, causative or potentially pathogenic variants were predicted correctly by at least one group. However, the prediction of the correct causative variant seems to be insufficient to predict the correct phenotype. In some cases, the correct prediction has been supported by rare or common variants in genes different from the causative one.

6.
Bioinformatics ; 35(9): 1536-1543, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30304494

RESUMO

MOTIVATION: Precision medicine is an emerging field with hopes to improve patient treatment and reduce morbidity and mortality. To these ends, computational approaches have predicted associations among genes, chemicals and diseases. Such efforts, however, were often limited to using just some available association types. This lowers prediction coverage and, since prior evidence shows that integrating heterogeneous data is likely beneficial, it may limit accuracy. Therefore, we systematically tested whether using more association types improves prediction. RESULTS: We study multimodal networks linking diseases, genes and chemicals (drugs) by applying three diffusion algorithms and varying information content. Ten-fold cross-validation shows that these networks are internally consistent, both within and across association types. Also, diffusion methods recovered missing edges, even if all the edges from an entire mode of association were removed. This suggests that information is transferable between these association types. As a realistic validation, time-stamped experiments simulated the predictions of future associations based solely on information known prior to a given date. The results show that many future published results are predictable from current associations. Moreover, in most cases, using more association types increases prediction coverage without significantly decreasing sensitivity and specificity. In case studies, literature-supported validation shows that these predictions mimic human-formulated hypotheses. Overall, this study suggests that diffusion over a more comprehensive multimodal network will generate more useful hypotheses of associations among diseases, genes and chemicals, which may guide the development of precision therapies. AVAILABILITY AND IMPLEMENTATION: Code and data are available at https://github.com/LichtargeLab/multimodal-network-diffusion. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

7.
Hum Brain Mapp ; 40(6): 1829-1843, 2019 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-30569619

RESUMO

Several plausible theories of the neural implementation of speed/accuracy trade-off (SAT), the phenomenon in which individuals may alternately emphasize speed or accuracy during the performance of cognitive tasks, have been proposed, and multiple lines of evidence point to the involvement of the pre-supplemental motor area (pre-SMA). However, as the nature and directionality of the pre-SMA's functional connections to other regions involved in cognitive control and task processing are not known, its precise role in the top-down control of SAT remains unclear. Although recent advances in cross-sectional path modeling provide a promising way of characterizing these connections, such models are limited by their tendency to produce multiple equivalent solutions. In a sample of healthy adults (N = 18), the current study uses the novel approach of Group Iterative Multiple Model Estimation for Multiple Solutions (GIMME-MS) to assess directed functional connections between the pre-SMA, other regions previously linked to control of SAT, and regions putatively involved in evidence accumulation for the decision task. Results reveal a primary role of the pre-SMA for modulating activity in regions involved in the decision process but suggest that this region receives top-down input from the DLPFC. Findings also demonstrate the utility of GIMME-MS and solution-reduction methods for obtaining valid directional inferences from connectivity path models.

8.
J Psychopathol Behav Assess ; 40(1): 107-116, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30505069

RESUMO

The Balloon Analogue Risk Task (BART) is a behavioral measure that is commonly used to assess risk taking propensity. The primary goal of the present study was to introduce a mobile version of the BART (mBART) that can be included within ambulatory assessment protocols to assess risk taking in daily life. Study 1 compared common BART indices (i.e., total money earned, adjusted average pumps, balloon explosions, and coefficient of variability [CV]) on a single administration of the laboratory BART on a computer and the mBART on a smartphone (n = 78). Results revealed generally consistent relationships between indices of risk taking propensity in both the laboratory BART and mBART. Study 2 administered the mBART as part of a 7-day ecological momentary assessment (EMA) protocol in a population of nondaily smokers (n = 51). Using multi-level models, results suggest that males have greater adjusted average pumps (p = .03), and that a participant's average CV is negatively related to trait sensation seeking (p = .03) and positively associated with trait positive urgency (p = .04). There were within-person effects of study day (p = .05) and environment (p = .02) with respect to adjusted average pumps such that individuals took greater risks as the study progressed and were riskier when alone compared to with others. Inclusion of the mBART in EMA did not appear to significantly increase participant burden and demonstrated acceptable levels of compliance. These results offer initial evidence supporting the feasibility and utility of the mBART for ambulatory research designs.

9.
Pediatr Pulmonol ; 53(5): 645-655, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29575753

RESUMO

STUDY OBJECTIVES: Pulse-oximetry (SpO2 ) allows the identification of important clinical physiology. However, summary statistics such as mean values and desaturation incidence do not capture the complexity of the information contained within continuous recordings. The aim of this study was to develop an objective method to quantify important SpO2 characteristics; and assess its utility in healthy infant and preterm neonate cohorts. METHODS: An algorithm was developed to calculate the desaturation incidence, depth, and duration. These variables are presented using three plots: SpO2 cumulative-frequency relationship; desaturation-depth versus incidence; desaturation-duration versus incidence. This method was applied to two populations who underwent nocturnal pulse-oximetry: (1) thirty-four healthy term infants studied at 2-weeks, 3, 6, 12, and 24-months of age and (2) thirty-seven neonates born <26 weeks and studied at discharge from NICU (37-44 weeks post-conceptual age). RESULTS: The maturation in healthy infants was characterized by reduced desaturation index (27.2/h vs 3.3/h at 2-weeks and 24-months, P < 0.01), and increased percentage of desaturation events ≥6-s in duration (27.8% vs 43.2% at 2-weeks and 3-months, P < 0.01). Compared with term-infants, preterm infants had a greater desaturation incidence (54.8/h vs 27.2/h, P < 0.01), and these desaturations were deeper (52.9% vs 37.6% were ≥6% below baseline, P < 0.01). The incidence of longer desaturations (≥14-s) in preterm infants was correlated with healthcare utilization over the first 24-months (r = 0.63, P < 0.01). CONCLUSIONS: This tool allows the objective comparison of extended oximetry recordings between groups and for individuals; and serves as a basis for the development of reference ranges for populations.


Assuntos
Recém-Nascido Prematuro/fisiologia , Oximetria/métodos , Gráficos por Computador , Feminino , Humanos , Lactente , Saúde do Lactente , Recém-Nascido , Masculino , Oxigênio/fisiologia
10.
J Pers Disord ; 32(Suppl): 36-57, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29388895

RESUMO

Deficits in identity as well as negative affect have been shown to predict self-injurious and suicidal behaviors in individuals with borderline personality disorder (BPD). However, less is known about the interactive effects of these two predictors. We examined the moderating effect of a particular component of identity, self-concept, on the relationship between negative affect and self-injurious urges utilizing ecological momentary assessments. Outpatients diagnosed with either BPD (n = 36) or any anxiety disorder but no BPD (n = 18) completed surveys throughout the day over a 21-day period. Higher levels of momentary negative affect predicted greater subsequent urges to self-injure, but only when self-concept clarity was low (z = -3.60, p < .01). This effect did not differ between diagnostic groups. The results suggest that self-concept clarity has a protective effect against self-injurious urges in light of high negative affect, and that this effect may be transdiagnostic.


Assuntos
Afeto , Transtorno da Personalidade Borderline/complicações , Avaliação Momentânea Ecológica/estatística & dados numéricos , Avaliação Momentânea Ecológica/normas , Autoimagem , Comportamento Autodestrutivo/diagnóstico , Ideação Suicida , Adolescente , Adulto , Transtorno da Personalidade Borderline/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pacientes Ambulatoriais , Comportamento Autodestrutivo/psicologia , Inquéritos e Questionários
11.
Appetite ; 125: 139-151, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29408590

RESUMO

Large portions promote intake of energy dense foods (i.e., the portion size effect--PSE), but the neurobiological drivers of this effect are not known. We tested the association between blood oxygen level dependent (BOLD) brain response to food images varied by portion size (PS) and energy density (ED) and children's intake at test-meals of high- and low-ED foods served at varying portions. Children (N = 47; age 7-10 years) participated in a within-subjects, crossover study consisting of 4 meals of increasing PS of high- and low-ED foods and 1 fMRI to evaluate food images at 2 levels of PS (Large, Small) and 2 levels of ED (High, Low). Contrast values between PS conditions (e.g., Large PS - Small PS) were calculated from BOLD signal in brain regions implicated in cognitive control and reward and input as covariates in mixed models to determine if they moderated the PSE curve. Results showed a significant effect of PS on intake. Responses to Large relative to Small PS in brain regions implicated in salience (e.g., ventromedial prefrontal cortex and orbitofrontal cortex) were positively associated with the linear slope (i.e., increase in intake from baseline) of the PSE curve, but negatively associated with the quadratic coefficient for the total meal. Responses to Large PS High ED relative to Small PS High ED cues in regions associated with cognitive control (e.g., dorsolateral prefrontal cortex) were negatively associated with the linear slope of the PSE curve for high-ED foods. Brain responses to PS cues were associated with individual differences in children's susceptibility to overeating from large portions. Responses in food salience regions positively associated with PSE susceptibility while activation in control regions negatively associated with PSE susceptibility.


Assuntos
Encéfalo/diagnóstico por imagem , Comportamento Alimentar/psicologia , Individualidade , Imagem por Ressonância Magnética , Tamanho da Porção/psicologia , Encéfalo/fisiologia , Criança , Estudos Cross-Over , Sinais (Psicologia) , Feminino , Humanos , Masculino , Refeições , Estimulação Luminosa/métodos
12.
Brain Res Bull ; 138: 56-63, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28528203

RESUMO

Resting state functional brain connectivity (rsFC) may be an important neuromarker of smoking behavior. Prior research has shown, among cigarette smokers, that nicotine administration alters rsFC within frontal and parietal cortices involved in executive control, as well as striatal regions that drive reward processing. These changes in rsFC have been associated with reductions in withdrawal symptom severity. We currently have a limited understanding of how rsFC is affected by the use of electronic cigarettes (ecigs), an increasingly popular class of products, the members of which deliver nicotine with varying effectiveness. The current study used fMRI to determine the effects of ecig use on rsFC and withdrawal symptoms. Independent component, dual regression, and permutation analyses were conducted on rsFC collected from ecig users before and after an ecig use episode (n=9) that occurred after 14h of nicotine abstinence. Similar to the known effects of nicotine administration, ecig use decreased rsFC of two clusters in the right frontal pole and frontal medial cortex with an attentional control salience network, and decreased rsFC of five clusters in the left thalamus, insula, and brain stem with a reward network encompassing the striatum. Ecig use increased inverse coupling between the prefrontal reward network and the right frontoparietal executive control network. Reductions in craving and difficulty with concentration were correlated with decreases in coupling strength between reward and executive control networks. These preliminary results suggest that the effects of ecig use on rsFC are similar to those seen with nicotine administration in other forms. In order to gain insight into the addictive potential of ecigs, further research is needed to understand the neural influence of ecigs across the range of nicotine delivery within this class of products.


Assuntos
Encéfalo/diagnóstico por imagem , Rede Nervosa/diagnóstico por imagem , Descanso , Síndrome de Abstinência a Substâncias/etiologia , Síndrome de Abstinência a Substâncias/patologia , Vaping , Adulto , Encéfalo/efeitos dos fármacos , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Rede Nervosa/efeitos dos fármacos , Nicotina/farmacologia , Agonistas Nicotínicos/farmacologia , Oxigênio/sangue , Análise de Componente Principal , Autorrelato , Vaping/patologia , Vaping/fisiopatologia , Vaping/psicologia
13.
Respir Physiol Neurobiol ; 244: 32-40, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28676331

RESUMO

Short pauses or "transition-periods" at the end of expiration and prior to subsequent inspiration are commonly observed during sleep in humans. However, the role of transition periods in regulating ventilation during physiological challenges such as partial airway obstruction (PAO) has not been investigated. Twenty-nine obstructive sleep apnea patients and eight controls underwent overnight polysomnography with an epiglottic catheter. Sustained-PAO segments (increased epiglottic pressure over ≥5 breaths without increased peak inspiratory flow) and unobstructed reference segments were manually scored during apnea-free non-REM sleep. Nasal pressure data was computationally segmented into inspiratory (TI, shortest period achieving 95% inspiratory volume), expiratory (TE, shortest period achieving 95% expiratory volume), and inter-breath transition period (TTrans, period between TE and subsequent TI). Compared with reference segments, sustained-PAO segments had a mean relative reduction in TTrans (-24.7±17.6%, P<0.001), elevated TI (11.8±10.5%, P<0.001), and a small reduction in TE (-3.9±8.0, P≤0.05). Compensatory increases in inspiratory period during PAO are primarily explained by reduced transition period and not by reduced expiratory period.


Assuntos
Algoritmos , Respiração , Processamento de Sinais Assistido por Computador , Apneia Obstrutiva do Sono/fisiopatologia , Sono/fisiologia , Humanos , Polissonografia , Decúbito Dorsal , Fatores de Tempo
14.
Nicotine Tob Res ; 19(6): 716-722, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28486711

RESUMO

Introduction: Research suggests that a blunted response to nondrug rewards, especially under conditions associated with strong cigarette cravings, is associated with reduced abstinence motivation in daily smokers. One limitation of previous studies is that they have largely focused on monetary rewards as broad representative of nondrug rewards. It remains unclear whether craving dampens responses to more abstract nondrug rewards, such as personal values. Personal values often have a positive valence and are frequently assumed to remain stable across time and situations. However, there may be time-varying and contextual influences on smokers' appraisal of values in daily life. Characterizing fluctuations in value importance in relation to relapse precipitants (eg, craving) may inform interventions that leverage personal values as motivation for cessation. Methods: Daily smokers (n = 18) completed ecological momentary assessment surveys measuring the importance of specific personal values and smoking-related variables during 8 days of monetarily reinforced cigarette abstinence. We hypothesized that value ratings would demonstrate adequate within-person heterogeneity for multilevel modeling and that within-person fluctuations in craving would be negatively related to valuing personal health. Results: All values demonstrated adequate within-person variability for multilevel modeling. Within-person craving was negatively related to health valuation (p = .012) and a cross-level interaction (p > .0001) suggested this effect is stronger for individuals who report greater overall craving. Conclusions: Greater craving is associated with decreased importance of personal health in the moment, particularly for those with high average levels of craving. Timely interventions that bolster importance of health during moments of elevated craving can potentially improve cessation outcomes. Implications: This study builds on research highlighting the positive influence of personal values in motivating behavior change. Values are an often used, but poorly studied, construct that has considerable utility in smoking cessation. Valuing personal health is frequently reported as a primary motivator for a quit attempt. Inasmuch as personal health is a distal nondrug reward used to motivate smoking abstinence, naturalistic evaluation of health importance, and motivators for continued smoking (ie, craving) could inform the timing and content of smoking treatment. This study is among the first to evaluate momentary assessment of personal values and craving within daily life.


Assuntos
Atitude Frente a Saúde , Fissura , Recompensa , Abandono do Hábito de Fumar/psicologia , Fumar/psicologia , Tabagismo/psicologia , Humanos , Motivação
15.
Nicotine Tob Res ; 19(6): 670-676, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28486716

RESUMO

Introduction: Smoking-related cues can promote drug-seeking behavior and curtail attempts to quit. One way to understand the potential impact of such cues is to compare cue-elicited behaviors for smoking and other reinforcers (eg, food) using the Pavlovian-to-instrumental transfer paradigm, which measures how much control cues can exert over reward-seeking responses. Methods: We tested the influence of appetitive cues on smokers' behavior following 12 hours of abstinence from smoking and eating. First, we equated the value of cigarette and food by assessing a Willingness-to-Pay measure for each reinforcer. Second, we evaluated behavioral differences between cues with Pavlovian-to-instrumental transfer. In two phases, participants learned (1) the association between distinct stimuli and cigarette or food outcomes and, (2) specific instrumental responses that yielded such outcomes. Motivated behavior was probed under extinction in a subsequent transfer test assessing instrumental responding in the presence of the cues. Results: Participants showed an increase in specific responding (eg, instrumental response associated with cigarette) when faced with the corresponding appetitive cue (eg, stimulus associated with cigarette) despite absence of outcome. Notably, they made more cigarette-seeking than food-seeking instrumental responses, suggesting that cues representative of cigarette outcomes exert stronger influences on behavior than non-drug (food) cues. Using a measure of subjective preference, we also observed that greater preference for cigarette-compared to food-cues correlated with increased cigarette-seeking behavior in the test phase. Conclusion: Taken together, these results highlight how drug and non-drug cues differentially influence reward-seeking behaviors during deprivation, which has implications for smoking cessation treatment and relapse. Implications: This study examines the motivational influence of both drug and non-drug cues within a single sample of cigarette smokers. Our results demonstrate that the motivational properties of smoking cues differ from cues relating to other types of reward, such as food. This research informs smoking cessation programs to target the salience of nicotine cues and the maladaptive drug-seeking behaviors prompted by them.


Assuntos
Sinais (Psicologia) , Comportamento Alimentar , Fumantes/psicologia , Tabagismo , Adulto , Comportamento Alimentar/fisiologia , Comportamento Alimentar/psicologia , Feminino , Humanos , Masculino , Motivação , Abandono do Hábito de Fumar , Tabagismo/fisiopatologia , Tabagismo/psicologia , Adulto Jovem
16.
J Pers Disord ; 31(3): 289-305, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-27064849

RESUMO

Borderline personality disorder (BPD) and alcohol use disorder (AUD) share impulsivity as an etiological factor. However, impulsivity is ill-defined, often overlapping with self-control capacity. This study attempts to disentangle these constructs and their associations with alcohol use and BPD. Undergraduates (n = 192) completed the Five Factor Model Rating Form, which generated two-dimensional scales of BPD, the Self-Control Scale, the UPPS-P (self-reported impulsivity), and the stop-signal and delay discounting tasks (laboratory-measured impulsivity). Self-control appeared as a major predictor of BPD features and drinking, explaining as much or more variance in outcome than impulsivity. Co-occurrence of elevated BPD features and problem drinking was also best explained by self-control. Laboratory measures of impulsivity were not correlated with BPD scales or alcohol use. Self-regulatory capacity may be an important but overlooked factor in BPD and alcohol use and should be considered alongside impulsivity in future research.


Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Transtorno da Personalidade Borderline/complicações , Autocontrole/psicologia , Adulto , Consumo de Bebidas Alcoólicas/psicologia , Comorbidade , Feminino , Humanos , Comportamento Impulsivo , Masculino , Adulto Jovem
17.
Neuroimage ; 151: 24-32, 2017 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-26975550

RESUMO

Quitting smoking is the single best change in behavior that smokers can make to improve their health and extend their lives. Although most smokers express a strong desire to stop using cigarettes, the vast majority of quit attempts end in relapse. Relapse is particularly likely when smokers encounter cigarette cues. A striking number of relapses occur very quickly, with many occurring within as little as 24h. Characterizing what distinguishes successful quit attempts from unsuccessful ones, particularly just after cessation is initiated, is a research priority. We addressed this significant issue by examining the association between functional connectivity during cigarette cue exposure and smoking behavior during the first 24h of a quit attempt. Functional MRI was used to measure brain activity during cue exposure in nicotine-deprived daily smokers during the first day of a quit attempt. Participants were then given the opportunity to smoke. Using data collected in two parent studies, we identified a subset of participants who chose to smoke and a matched subset who declined (n=38). Smokers who were able to resist smoking displayed significant functional connectivity between the left anterior insula and the dorsolateral prefrontal cortex, whereas there was no such connectivity for those who chose to smoke. Notably, there were no differences in mean levels of activation in brain regions of interest, underscoring the importance of assessing interregional connectivity when investigating the links between cue-related neural responses and overt behavior. To our knowledge, this is the first study to link patterns of functional connectivity and actual cigarette use during the pivotal first hours of attempt to change smoking behavior.


Assuntos
Encéfalo/fisiopatologia , Sinais (Psicologia) , Abandono do Hábito de Fumar , Tabagismo/fisiopatologia , Tabagismo/psicologia , Adulto , Córtex Cerebral/fisiopatologia , Fumar Cigarros , Feminino , Humanos , Masculino , Vias Neurais/fisiopatologia , Córtex Pré-Frontal/fisiopatologia , Tabagismo/prevenção & controle
18.
Am J Clin Nutr ; 105(2): 295-305, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27881393

RESUMO

BACKGROUND: Large portions of food promote intake, but the mechanisms that drive this effect are unclear. Previous neuroimaging studies have identified the brain-reward and decision-making systems that are involved in the response to the energy density (ED) (kilocalories per gram) of foods, but few studies have examined the brain response to the food portion size (PS). OBJECTIVE: We used functional MRI (fMRI) to determine the brain response to food images that differed in PSs (large and small) and ED (high and low). DESIGN: Block-design fMRI was used to assess the blood oxygen level-dependent (BOLD) response to images in 36 children (7-10 y old; girls: 50%), which was tested after a 2-h fast. Pre-fMRI fullness and liking were rated on visual analog scales. A whole-brain cluster-corrected analysis was used to compare BOLD activation for main effects of the PS, ED, and their interaction. Secondary analyses were used to associate BOLD contrast values with appetitive traits and laboratory intake from meals for which the portions of all foods were increased. RESULTS: Compared with small-PS cues, large-PS cues were associated with decreased activation in the inferior frontal gyrus (P < 0.01). Compared with low-ED cues, high-ED cues were associated with increased activation in multiple regions (e.g., in the caudate, cingulate, and precentral gyrus) and decreased activation in the insula and superior temporal gyrus (P < 0.01 for all). A PS × ED interaction was shown in the superior temporal gyrus (P < 0.01). BOLD contrast values for high-ED cues compared with low-ED cues in the insula, declive, and precentral gyrus were negatively related to appetitive traits (P < 0.05). There were no associations between the brain response to the PS and either appetitive traits or intake. CONCLUSIONS: Cues regarding food PS may be processed in the lateral prefrontal cortex, which is a region that is implicated in cognitive control, whereas ED activates multiple areas involved in sensory and reward processing. Possible implications include the development of interventions that target decision-making and reward systems differently to moderate overeating.


Assuntos
Encéfalo/fisiologia , Ingestão de Energia , Tamanho da Porção , Adiposidade , Índice de Massa Corporal , Criança , Comportamento Infantil , Análise por Conglomerados , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imagem por Ressonância Magnética , Masculino , Neuroimagem
19.
Pac Symp Biocomput ; 22: 336-347, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27896987

RESUMO

Advances in cellular, molecular, and disease biology depend on the comprehensive characterization of gene interactions and pathways. Traditionally, these pathways are curated manually, limiting their efficient annotation and, potentially, reinforcing field-specific bias. Here, in order to test objective and automated identification of functionally cooperative genes, we compared a novel algorithm with three established methods to search for communities within gene interaction networks. Communities identified by the novel approach and by one of the established method overlapped significantly (q < 0.1) with control pathways. With respect to disease, these communities were biased to genes with pathogenic variants in ClinVar (p ≪ 0.01), and often genes from the same community were co-expressed, including in breast cancers. The interesting subset of novel communities, defined by poor overlap to control pathways also contained co-expressed genes, consistent with a possible functional role. This work shows that community detection based on topological features of networks suggests new, biologically meaningful groupings of genes that, in turn, point to health and disease relevant hypotheses.


Assuntos
Mapas de Interação de Proteínas , Algoritmos , Síndrome de Bardet-Biedl/genética , Neoplasias da Mama/genética , Biologia Computacional , Epistasia Genética , Feminino , Redes Reguladoras de Genes , Predisposição Genética para Doença , Humanos , Mapas de Interação de Proteínas/genética , Síndrome de Zellweger/genética
20.
Sensors (Basel) ; 16(9)2016 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-27598157

RESUMO

Optical interrogation of suspicious skin lesions is standard care in the management of skin cancer worldwide. Morphological and functional markers of malignancy are often combined to improve expert human diagnostic power. We propose the evaluation of the combination of two independent optical biomarkers of skin tumours concurrently. The morphological modality of reflectance confocal microscopy (RCM) is combined with the functional modality of laser Doppler flowmetry, which is capable of quantifying tissue perfusion. To realize the idea, we propose laser feedback interferometry as an implementation of RCM, which is able to detect the Doppler signal in addition to the confocal reflectance signal. Based on the proposed technique, we study numerical models of skin tissue incorporating two optical biomarkers of malignancy: (i) abnormal red blood cell velocities and concentrations and (ii) anomalous optical properties manifested through tissue confocal reflectance, using Monte Carlo simulation. We also conduct a laboratory experiment on a microfluidic channel containing a dynamic turbid medium, to validate the efficacy of the technique. We quantify the performance of the technique by examining a signal to background ratio (SBR) in both the numerical and experimental models, and it is shown that both simulated and experimental SBRs improve consistently using this technique. This work indicates the feasibility of an optical instrument, which may have a role in enhanced imaging of skin malignancies.


Assuntos
Diagnóstico por Imagem , Fluxometria por Laser-Doppler/métodos , Microscopia Confocal/métodos , Método de Monte Carlo , Neoplasias Cutâneas/diagnóstico , Humanos , Interferometria , Análise Numérica Assistida por Computador , Reprodutibilidade dos Testes , Processamento de Sinais Assistido por Computador
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