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1.
BMC Infect Dis ; 23(1): 650, 2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37789266

RESUMO

BACKGROUND: Calprotectin is an inflammatory marker mainly released by activated neutrophils that is increased in acute severe COVID-19. After initial recovery, some patients have persistent respiratory impairment with reduced diffusion capacity of the lungs for carbon monoxide (DLCO) months after infection. Underlying causes of this persistent impairment are unclear. We aimed to investigate the correlation between circulating calprotectin, persistent lung functional impairment and intensive care unit (ICU) stay after COVID-19 in two university hospital centres in Switzerland. METHODS: Calprotectin levels were measured in serum from 124 patients (50% male) from the Bern cohort (post-ICU and non-ICU patients) and 68 (76% male) from the Lausanne cohort (only post-ICU patients) four months after COVID-19. Calprotectin was correlated with clinical parameters. Multivariate linear regression (MLR) was performed to evaluate the independent association of calprotectin in different models. RESULTS: Overall, we found that post-ICU patients, compared to non-ICU, were significantly older (age 59.4 ± 13.6 (Bern), 60.5 ± 12.0 (Lausanne) vs. 48.8 ± 13.4 years) and more obese (BMI 28.6 ± 4.5 and 29.1 ± 5.3 vs. 25.2 ± 6.0 kg/m2, respectively). 48% of patients from Lausanne and 44% of the post-ICU Bern cohort had arterial hypertension as a pre-existing comorbidity vs. only 10% in non-ICU patients. Four months after COVID-19 infection, DLCO was lower in post-ICU patients (75.96 ± 19.05% predicted Bern, 71.11 ± 18.50% Lausanne) compared to non-ICU (97.79 ± 21.70% predicted, p < 0.01). The post-ICU cohort in Lausanne had similar calprotectin levels when compared to the cohort in Bern (Bern 2.74 ± 1.15 µg/ml, Lausanne 2.49 ± 1.13 µg/ml vs. non-ICU 1.86 ± 1.02 µg/ml; p-value < 0.01). Calprotectin correlated negatively with DLCO (r= -0.290, p < 0.001) and the forced vital capacity (FVC) (r= -0.311, p < 0.001). CONCLUSIONS: Serum calprotectin is elevated in post-ICU patients in two independent cohorts and higher compared to non-ICU patients four months after COVID-19. In addition, there is a negative correlation between calprotectin levels and DLCO or FVC. The relationship between inflammation and lung functional impairment needs further investigations. TRIAL REGISTRATION: NCT04581135.


Assuntos
COVID-19 , Hipertensão , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cuidados Críticos , Hospitais Universitários , Complexo Antígeno L1 Leucocitário , Pulmão
2.
Artif Organs ; 47(4): 705-720, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36720049

RESUMO

BACKGROUND AND OBJECTIVE: The intrinsic electrical material properties of the laminar components of the mammalian peripheral nerve bundle are important parameters necessary for the accurate simulation of the electrical interaction between nerve fibers and neural interfaces. Improvements in the accuracy of these parameters improve the realism of the simulation and enables realistic screening of novel devices used for extracellular recording and stimulation of mammalian peripheral nerves. This work aims to characterize these properties for mammalian peripheral nerves to build upon the resistive parameter set established by Weerasuriya et al. in 1984 for amphibian somatic peripheral nerves (frog sciatic nerve) that is currently used ubiquitously in the in-silico peripheral nerve modeling community. METHODS: A custom designed characterization chamber was implemented and used to measure the radial and longitudinal impedance between 10 mHz and 50 kHz of freshly excised canine vagus nerves using four-point impedance spectroscopy. The impedance spectra were parametrically fitted to an equivalent circuit model to decompose and estimate the components of the various laminae. Histological sections of the electrically characterized nerves were then made to quantify the geometry and laminae thicknesses of the perineurium and epineurium. These measured values were then used to calculate the estimated intrinsic electrical properties, resistivity and permittivity, from the decomposed resistances and reactances. Finally, the estimated intrinsic electrical properties were used in a finite element method (FEM) model of the nerve characterization setup to evaluate the realism of the model. RESULTS: The geometric measurements were as follows: nerve bundle (1.6 ± 0.6 mm), major nerve fascicle diameter (1.3 ± 0.23 mm), and perineurium thickness (13.8 ± 2.1 µm). The longitudinal resistivity of the endoneurium was estimated to be 0.97 ± 0.05 Ωm. The relative permittivity and resistivity of the perineurium were estimated to be 2018 ± 391 and 3.75 kΩm ± 981 Ωm, respectively. The relative permittivity and resistivity of the epineurium were found to be 9.4 × 106 ± 8.2 × 106 and 55.0 ± 24.4 Ωm, respectively. The root mean squared (RMS) error of the experimentally obtained values when used in the equivalent circuit model to determine goodness of fit against the measured impedance spectra was found to be 13.0 ± 10.7 Ω, 2.4° ± 1.3°. The corner frequency of the perineurium and epineurium were found to be 2.6 ± 1.0 kHz and 368.5 ± 761.9 Hz, respectively. A comparison between the FEM model in-silico impedance experiment against the ex-vivo methods had a RMS error of 159.0 ± 95.4 Ω, 20.7° ± 9.8°. CONCLUSION: Although the resistive values measured in the mammalian nerve are similar to those of the amphibian model, the relative permittivity of the laminae bring new information about the reactance and the corner frequency (frequency at peak reactance) of the peripheral nerve. The measured and estimated corner frequency are well within the range of most bioelectric signals, and are important to take into account when modeling the nerve and neural interfaces.


Assuntos
Nervos Periféricos , Nervo Isquiático , Animais , Cães , Nervos Periféricos/fisiologia , Nervo Isquiático/fisiologia , Convulsões , Mamíferos
3.
J Behav Med ; 46(3): 405-416, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36260160

RESUMO

Physical activity (PA) plays an integral role in reducing risk for the leading causes of death and has also been shown to buffer stress. Based on the stress-buffering hypothesis, the present study examined whether protective factors (self-efficacy and informal social control) buffered the effects of perceived stress on PA over time. Secondary data analyses of female African American caregivers (N = 143) were conducted using data from the Families Improving Together (FIT) trial. Validated measures of stressors and protective factors were assessed at baseline. Light PA and moderate-to-vigorous PA were assessed using seven-day accelerometry estimates over sixteen weeks. Multilevel growth modeling was used to assess whether protective factors moderated the effects of perceived stress on PA outcomes across 16 weeks. There was a significant two-way interaction between informal social control and time (B = 0.40, SE = 0.17, p = .019) such that higher informal social control was positively associated with MVPA over time. There was a marginal three-way interaction (B = -18.90, SE = 10.31, p = .067) such that stress was associated with greater LPA at baseline under conditions of high but not low self-efficacy. This study provides preliminary support that social factors may be important for maintaining MVPA regardless of stress levels, while cognitive resources may be more important to target for influencing LPA engagement under conditions of high stress.


Assuntos
Negro ou Afro-Americano , Exercício Físico , Feminino , Humanos , Acelerometria , Exercício Físico/psicologia , Fatores de Proteção
4.
J Med Internet Res ; 25: e42581, 2023 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-37043271

RESUMO

BACKGROUND: Web-based tailored interventions offer rich opportunities for improved access to and personalization of behavioral interventions. However, despite the promise of this approach, the engagement and underrepresentation of minority groups remain major issues. OBJECTIVE: This study evaluated whether engagement (log-in status and log-in duration) with different types of tailored behavioral content from the Families Improving Together for weight loss web-based intervention was associated with changes in moderate to vigorous physical activity (MVPA) among African American families with overweight or obesity. METHODS: Parent-adolescent dyads were randomized to a web-based tailored intervention or web-based health education comparison program. The web-based intervention (N=119) was completed by parents and targeted 6 weight-related behaviors to support their adolescent children's weight loss goals (session contents included energy balance, fast food, fruits and vegetables, physical activity [PA], sedentary behavior, and sweetened beverages). MVPA was measured using accelerometers at baseline and after the intervention. RESULTS: Using a hierarchical approach, the log-in status and duration for each web-based session were used to evaluate the additive effects of engagement with different types of tailored behavioral content on MVPA after the web-based intervention. Among parents, logging in to the PA session was not associated with greater MVPA (B=-12.561, 95% CI -18.759 to -6.367), but MVPA increased with greater log-in duration for the PA (B=0.008, 95% CI 0.004-0.012) and sedentary behavior (B= 0.008, 95% CI 0.004-0.012) sessions. These results suggest that parents who logged in to the PA session had lower MVPA, but MVPA increased with greater log-in duration for the PA and sedentary behavior sessions. These associations remained even after accounting for engagement with other content sessions. However, these engagement effects did not translate to the adolescents. CONCLUSIONS: The results of this study highlight the need to disentangle the impact of engagement with different tailored content to improve the efficacy of tailored web-based interventions, especially for promoting PA in African American families. TRIAL REGISTRATION: ClinicalTrials.gov NCT01796067; https://clinicaltrials.gov/ct2/show/NCT01796067.


Assuntos
Exercício Físico , Redução de Peso , Criança , Adolescente , Humanos , Pais , Promoção da Saúde/métodos , Terapia Comportamental
5.
Encephale ; 49(3): 289-295, 2023 Jun.
Artigo em Francês | MEDLINE | ID: mdl-35331468

RESUMO

CONTEXT: The high prevalence of psychiatric disorders among people in prison is well documented, and several hypotheses have been proposed to explain this overrepresentation. In France, the decrease in the number of people found by the judge to be not criminally responsible on account of mental disorder after a psychiatric expertise could play a crucial role. The Château-Thierry prison is a high-security correctional facility where prisoners whose integration into a "standard" prison is complicated because of behavioural problems, reside. We conducted the first study to describe the judicial and healthcare trajectories of people incarcerated in this facility. METHOD: All the people incarcerated in the Château-Thierry prison between May and September 2019 were included in this cross-sectional study. In addition to sociodemographic characteristics, data on the psychiatric care before and during incarceration as well as information on the judicial and prison history were collected. We also analyzed all the pre-sentencing psychiatric reports in order to collect the degree of discernment determined by the psychiatrist expert for each included individual. RESULTS: Sixty-eight (97%) of the 70 people detained at the Château-Thierry prison during the study period were included and 92 pre-sentencing psychiatric reports were analyzed. The population studied was exclusively male, with an average age of 40 years, low socio-economic status and frequent criminal history (79%). About half of them (46%) had already been hospitalized in a psychiatric community hospital prior to incarceration, and 79% have been hospitalized in a psychiatric facility during their incarceration. Disciplinary sanctions were frequent (72%) as well as convictions for offenses committed while in prison (57%). When at least one pre-sentencing psychiatric report was carried out (29 persons had a single psychiatric forensic evaluation and 27 ones had multiple evaluations), at least one psychiatric expert had concluded to a diminished (but not lack of) criminal responsibility in almost half of the cases (44%). CONCLUSION: This study shows the extent to which people incarcerated in the Château-Thierry prison are affected by psychiatric disorders. It also highlights the difficulties of coping with the prison environment for people suffering from psychiatric disorders. Finally, it raises the question of the lack of diversion programs for the individuals in France with mental health problems whose responsibility has been considered as full or diminished.


Assuntos
Criminosos , Transtornos Mentais , Prisioneiros , Humanos , Masculino , Adulto , Prisões , Estudos Transversais , Prisioneiros/psicologia , Transtornos Mentais/epidemiologia , Transtornos Mentais/terapia , Transtornos Mentais/psicologia , Criminosos/psicologia
6.
Ann Behav Med ; 56(10): 1042-1055, 2022 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-35226095

RESUMO

BACKGROUND: Few intervention studies have integrated cultural tailoring, parenting, behavioral, and motivational strategies to address African American adolescent weight loss. PURPOSE: The Families Improving Together (FIT) for Weight Loss trial was a randomized group cohort study testing the efficacy of a cultural tailoring, positive parenting, and motivational intervention for weight loss in overweight African American adolescents (N = 241 adolescent/caregiver dyads). METHODS: The trial tested an 8-week face-to-face group motivational plus family weight loss program (M + FWL) compared with a comprehensive health education control program. Participants were then rerandomized to an 8-week tailored or control online program to test the added effects of the online intervention on reducing body mass index and improving physical activity (moderate-to-vigorous physical activity [MVPA], light physical activity [LPA]), and diet. RESULTS: There were no significant intervention effects for body mass index or diet. There was a significant effect of the group M + FWL intervention on parent LPA at 16 weeks (B = 33.017, SE = 13.115, p = .012). Parents in the group M + FWL intervention showed an increase in LPA, whereas parents in the comprehensive health education group showed a decrease in LPA. Secondary analyses using complier average causal effects showed a significant intervention effect at 16 weeks for parents on MVPA and a similar trend for adolescents. CONCLUSIONS: While the intervention showed some impact on physical activity, additional strategies are needed to impact weight loss among overweight African American adolescents.


Assuntos
Negro ou Afro-Americano , Programas de Redução de Peso , Adolescente , Estudos de Coortes , Humanos , Sobrepeso/terapia , Redução de Peso
7.
Artif Organs ; 46(10): 2073-2084, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35896504

RESUMO

BACKGROUND: In-silico experiments used to optimize and inform how peripheral nerve based electrode designs perform hold the promise of greatly reducing the guesswork with new designs as well as the number of animals used to identify and prove promising designs. Given adequate realism, in-silico experiments offer the promise of identifying putative mechanisms that further inform exploration of novel stimulation and recording techniques and their interactions with bioelectric phenomena. However, despite using validated nerve fiber models, when applied to the more complex case of an implanted extracellular electrode, the in-silico experiments often do not compare quantitatively with the results of experiments conducted in in-vivo experiments. This suggests that the accuracy/realism of the environment and the lamination of the nerve bundle plays an important role in this discrepancy. This paper describes the sensitivity of in-silico models to the electrical parameter estimates and volume conductor type used. METHODS: In-vivo work was performed on rat vagus nerves (N = 2) to characterize the strength-duration curve for various peaks identified in a compound nerve action potential (CAP) measured via a needle electrode. The vagus nerve has several distinct populations of nerve fiber calibers and types. Recruitment of a fiber caliber/type generates distinct peaks that can be identified, and whose conduction delay correlates to a conduction velocity. Peaks were identified by their recruitment thresholds and associated to their conduction velocities by the conduction delays of their peaks. An in-silico analog of the in-vivo experiment was constructed and experiments were run at the two extreme volume conductor cases: (1) The nerve in-saline, and (2) the nerve in-air. The specifically targeted electrical parameters were extraneural environment (in-air versus saline submersion), the resistivity (ρ) of the epineurium and perineurium, and the relative permittivity (εr ) of those same tissues. A time varying finite element method (FEM) model of the potential distribution vs time was quantified and projected onto a modified McIntyre, Richardson, and Grill (MRG), myelinated spinal nerve, active fiber model in NEURON to identify the threshold of activation as a function of stimulus pulse amplitude versus pulse width versus fiber diameter. The in-silico results were then compared to the in-vivo results. RESULTS: The finite element method simulations spanned two macro environments: in-saline and in-air. For these environments, the resistivities for low and high frequencies as well as two different permittivity cases were used. Between these 8 cases unique cases it was found that the most accurate combination of those variables was the in-air environment for low-frequency resistivity (ρ0 ) and ex-vivo a measured permittivity (εr,measured ) from unpublished ex-vivo experiments in canine vagal nerve, achieving a high degree of convergence (r2  = 0.96). As the in-vivo work was conducted in in-air, the in-air boundary condition test case was convergent with the in-silico results. CONCLUSIONS: The results of this investigation suggest that increasing realism in simulations begets more accurate predictions. Of particular importance are (ρ) and extraneural environment, with reactive electrical parameters becoming important for input waveforms with energy in higher frequencies.


Assuntos
Modelos Neurológicos , Nervos Periféricos , Animais , Simulação por Computador , Cães , Estimulação Elétrica , Eletrodos Implantados , Fibras Nervosas Mielinizadas/fisiologia , Nervos Periféricos/fisiologia , Ratos
8.
Artif Organs ; 46(10): 2085-2096, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35971860

RESUMO

BACKGROUND: The stimulation and recording performance of implanted neural interfaces are functions of the physical and electrical characteristics of the neural interface, its electrode material and structure. Therefore, rapid optimization of such characteristics is becoming critical in most clinical and research studies. This paper describes the development of an upgraded 3D printed cuff electrode shell design containing a novel intrinsically conductive polymer (ICP) for stimulation and recording of peripheral nerve fibers. METHODS: A 3D stereolithography (SLA) printer was used to print a scalable, custom designed, C-cuff electrode and I-beam closure for accurate, rapid implementation. A novel contact consisting of a percolated carbon graphite base electrodeposited with an intrinsically conductive polymer (ICP), poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) produced a PEDOT:PSS + carbon black (CB) matrix that was used to form the electrochemical interface on the structure. Prototype device performance was tested both in-vitro and in-vivo for electrical chemical capacity, electrochemical interfacial impedance, surgical handling, and implantability. The in-vivo work was performed on the sciatic nerve of 25 anesthetized Sprague Dawley rats to demonstrate recording and stimulating ability. RESULTS: Prototypes of different spatial geometries and number of contacts (bipolar, tripolar, and tetrapolar) were designed. The design was successfully printed with inner diameters down to 500 µm. Standard bipolar and tripolar cuffs, with a 1.3 mm inner diameter (ID), 0.5 mm contact width, 1.0 mm pitch, and a 1.5 mm end distance were used for the functional tests. This geometry was appropriate for placement on the rat sciatic nerve and enabled in-vivo testing in anesthetized rats. The contacts on the standard bipolar electrode had an area of 2.1 × 10-2  cm2 . Cyclic voltammetry on ICP coated and uncoated graphite contacts showed that the ICP increased the average charge storage capacity (CSC) by a factor of 30. The corresponding impedance at 1 Hz was slightly above 1 kΩ, a 99.99% decrease from 100 kΩ in the uncoated state. The statistical comparison of the pre- versus post-stimulation impedance measurements were not significantly different (p-value > 0.05). CONCLUSIONS: The new cuff electrode enables rapid development of cost-effective functional stimulation devices targeting nerve bundles less than 1.0 mm in diameter. This allows for recording and modulation of a low-frequency current targeted within the peripheral nervous system.


Assuntos
Carbono , Grafite , Animais , Compostos Bicíclicos Heterocíclicos com Pontes/química , Eletrodos , Eletrodos Implantados , Polímeros/química , Ratos , Ratos Sprague-Dawley , Fuligem , Estereolitografia
9.
J Behav Med ; 45(2): 211-226, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35032253

RESUMO

There is an increased interest in the use of personalized medicine approaches in the prevention or treatment of obesity, however, few studies have used these approaches to identify individual differences in treatment effects. The current study demonstrates the use of the predicted individual treatment effects framework to test for individual differences in the effects of the ACTION-PAC intervention, which targeted the treatment and prevention of obesity in a high school setting. We show how methods for personalized medicine can be used to test for significant individual differences in responses to an intervention and we discuss the potential and limitations of these methods. In our example, 25% of students in the preventive intervention, were predicted to have their BMI z-score reduced by 0.39 or greater, while at other end of the spectrum, 25% were predicted to have their BMI z-score increased by 0.09 or more. In this paper, we demonstrate and discuss the process of using methods for personalized medicine with interventions targeting adiposity and discuss the lessons learned from this application. Ultimately, these methods have the potential to be useful for clinicians and clients in choosing between treatment options, however they are limited in their ability to help researchers understand the mechanisms underlying these predictions.


Assuntos
Obesidade Infantil , Medicina de Precisão , Adiposidade , Índice de Massa Corporal , Humanos , Individualidade , Obesidade/prevenção & controle , Obesidade Infantil/prevenção & controle , Estudantes
10.
Encephale ; 48(4): 480-483, 2022 Aug.
Artigo em Francês | MEDLINE | ID: mdl-34538621

RESUMO

INTRODUCTION: The procedure of involuntary psychiatric hospitalization has been recently modified in France. Indeed, since 2011, a liberty and custody judge is appointed for each measure, to guarantee the rights of psychiatric inpatients and to prevent abusive hospitalizations. As a result, if procedural errors are noted, the liberty and custody judge may order the immediate ending of the psychiatric hospitalization. To date, only two studies described the reasons for judiciary discharge from involuntary psychiatric hospitalizations, but no study has been conducted in forensic psychiatric units for incarcerated people. The objective of the current study was to describe the main reasons judges use to decide on the irregularity of the hospitalization (against the opinion of psychiatrists) for detained patients, and to compare these reasons with those for patients in the community psychiatric unit. METHODS: We included all the discharges ordered between 2011 and 2018 in two units of the same hospital: a forensic psychiatric unit for incarcerated people and a community involuntary psychiatric unit. We extracted sociodemographic characteristics and judiciary information such as date of discharge, resason fordischarge, presence of the patient at the hearing. We analyzed the judge-ordered discharge rate (corresponding to the number of discharges divided by the number of involuntary psychiatric hospitalizations) for each year. Then, we examined the reason of discharge for each measure. RESULTS: One hundred and forty-seven discharges were analyzed: 73 in the psychiatric forensic unit and 73 in the community psychiatric unit. Rates of discharges were 6.7% and 8.8% for the forensic unit and the general psychiatric unit, respectively. Several reasons for the discharges were common for the two units (failure to inform the patient, lack of physical examination), but others were specific to the forensic unit, such as the impossibility for the patients to communicate with their lawyer, or the lack of immediate dangerousness for the person or for the others. CONCLUSION: This study highlights the specific aspects of involuntary psychiatric hospitalizations for people in prison in France. Future studies are needed to assess the impact of these judge-ordered discharge on patient's mental health, particularly for incarcerated patients.


Assuntos
Transtornos Mentais , Prisioneiros , Internação Compulsória de Doente Mental , França/epidemiologia , Hospitalização , Humanos , Transtornos Mentais/diagnóstico , Transtornos Mentais/epidemiologia , Transtornos Mentais/terapia , Alta do Paciente
11.
Ann Behav Med ; 55(4): 376-382, 2021 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-32692356

RESUMO

BACKGROUND: African American women participate in less physical activity (PA), have higher rates of chronic disease, and report higher perceived stress relative to other race and sex demographic groups. PURPOSE: Based on the stress-buffering hypothesis, this study tested the hypothesis that social support would buffer the negative effects of perceived stress on moderate-to-vigorous PA (MVPA) under high, but not low, perceived stress. METHODS: Participants were 143 African American women (mean [M] age = 43.94, standard deviation [SD] = 8.62; M body mass index = 37.94, SD = 8.11) enrolled in the Families Improving Together (FIT) for Weight Loss Trial. Average daily minutes of MVPA were obtained via 7 day accelerometer estimates at baseline and 8 and 16 weeks. RESULTS: A multilevel growth model demonstrated a significant three-way interaction between stress, social support, and time (B = -0.31, standard error [SE] = 0.14, p = .03). Simple slopes analyses revealed that, at baseline, among participants with high social support (+1 SD), stress was positively associated with greater MVPA (B = 0.49, SE = 0.18, p = .008), whereas among participants with low social support (-1 SD), stress was not significantly associated with MVPA (B = -0.04, SE = 0.14, p = .81). However, at 8 and 16 weeks, stress was not significantly associated with MVPA for either high or low support groups. CONCLUSIONS: Findings highlight the importance of integrating constructs of stress and social support into future physical activity intervention programs for African American women and the need to evaluate changes in stress and social support longitudinally.


Assuntos
Negro ou Afro-Americano/psicologia , Exercício Físico/psicologia , Apoio Social , Estresse Psicológico/etnologia , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Saúde da Mulher/etnologia
12.
Ann Behav Med ; 55(8): 708-719, 2021 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-32914830

RESUMO

BACKGROUND: Understanding determinants of metabolic risk has become a national priority given the increasingly high prevalence rate of this condition among U.S. adults. PURPOSE: This study's aim was to assess the impact of gene-by-neighborhood social environment interactions on waist circumference (WC) as a primary marker of metabolic risk in underserved African-American adults. Based on a dual-risk model, it was hypothesized that those with the highest genetic risk and who experienced negative neighborhood environment conditions would demonstrate higher WC than those with fewer risk factors. METHODS: This study utilized a subsample of participants from the Positive Action for Today's Health environmental intervention to improve access and safety for walking in higher-crime neighborhoods, who were willing to provide buccal swab samples for genotyping stress-related genetic pathways. Assessments were conducted with 228 African-American adults at baseline, 12, 18, and 24 months. RESULTS: Analyses indicated three significant gene-by-environment interactions on WC outcomes within the sympathetic nervous system (SNS) genetic pathway. Two interactions supported the dual-risk hypotheses, including the SNS genetic risk-by-neighborhood social life interaction (b = -0.11, t(618) = -2.02, p = .04), and SNS genetic risk-by-informal social control interaction (b = -0.51, t(618) = -1.95, p = .05) on WC outcomes. These interactions indicated that higher genetic risk and lower social-environmental supports were associated with higher WC. There was also one significant SNS genetic risk-by-neighborhood satisfaction interaction (b = 1.48, t(618) = 2.23, p = .02) on WC that was inconsistent with the dual-risk pattern. CONCLUSIONS: Findings indicate that neighborhood and genetic factors dually influence metabolic risk and that these relations may be complex and warrant further study. TRIAL REGISTRATION: NCT01025726.


Assuntos
Negro ou Afro-Americano/etnologia , Interação Gene-Ambiente , Características de Residência , Meio Social , Circunferência da Cintura , Adulto , Idoso , Fatores de Risco Cardiometabólico , Feminino , Predisposição Genética para Doença , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Obesidade/epidemiologia , Obesidade/genética , Satisfação Pessoal , Polimorfismo de Nucleotídeo Único , Ensaios Clínicos Controlados Aleatórios como Assunto , Controles Informais da Sociedade , Sistema Nervoso Simpático , Estados Unidos/epidemiologia , Estados Unidos/etnologia
13.
Eur Arch Psychiatry Clin Neurosci ; 271(4): 661-675, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32813032

RESUMO

In the current literature, two distinct and opposite models are suggested to explain the consciousness disorders in schizophrenia. The first one suggests that consciousness disorders rely on a low-level processing deficit, when the second model suggests that consciousness disorders rely on disruption in the ability to consciously access information, with preserved unconscious processing. The current study aims to understand the mechanisms associated with visual consciousness disorder in order to pave the road that will settle the debate regarding these hypotheses. During a functional magnetic resonance imaging session, 19 healthy participants (HC) and 15 patients with schizophrenia (SCZ) performed a visual detection task to compare the neural substrates associated with the conscious access to the visual inputs. The visual detection threshold was significantly higher in SCZ than in HC [t(32) = 3.37, p = 0.002]. Whole-brain ANOVA demonstrated that around the visual detection threshold patients with SCZ failed to activate a large network of brain areas compared to HC. (1) During conscious vision, HC engaged more the left cuneus and the right occipital cortex than patients with SCZ, (2) during unconscious vision, HC engaged a large network that patients with SCZ failed to activate, and finally, (3) during the access to consciousness process, patients with SCZ failed to activate the anterior cingulate cortex. These results suggest that the consciousness disorders in schizophrenia rely on specific dysfunctions depending on the consciousness stage. The disorders of the conscious vision are associated with dysfunction of occipital areas while the ones associated with unconscious vision rely on a large widespread network. Finally, the conscious access to the visual inputs is impaired by a dysfunction of the anterior cingulate cortex. The current study suggests that none of the two suggested models can explain consciousness disorders in schizophrenia. We suggest that there is an alternative model supporting that the conscious access to visual inputs is due to a disengagement of the supragenual anterior cingulate during the unconscious processing of the visual inputs associated with a sensory deficit.


Assuntos
Estado de Consciência , Esquizofrenia , Transtornos da Consciência/diagnóstico por imagem , Transtornos da Consciência/etiologia , Humanos , Imageamento por Ressonância Magnética , Esquizofrenia/complicações , Esquizofrenia/diagnóstico por imagem , Percepção Visual
14.
J Pediatr Psychol ; 46(8): 980-990, 2021 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-33738484

RESUMO

OBJECTIVE: This study set out to examine the role of parenting practices in protecting or exacerbating the negative effects of parent and adolescent stress on adolescent body mass index (BMI) over time. Separate longitudinal models were conducted to evaluate how parenting practices interacted with parental perceived stress and adolescent perceived stress in predicting adolescent BMI. METHODS: Baseline data were collected from 148 African American adolescents (Mage = 12.93, SD = 1.75; Mz-BMI = 0.78, SD = 0.50; MBMI%-ile = 96.7, SD = 3.90) and their caregivers (Mage = 44.45, SD = 8.65; MBMI = 37.63, SD = 8.21) enrolled in the Families Improving Together for Weight Loss trial. Adolescents self-reported their perceptions of caregiver parenting style and feeding practices. Both caregivers and adolescents self-reported their perceptions of chronic stress. BMI for parents and adolescents was assessed objectively at baseline and 16 weeks post-intervention. RESULTS: Hierarchical regression models predicting adolescent BMI z-score (z-BMI) indicated a significant interaction between parental perceived stress and parental pressure to eat. Simple slopes analyses demonstrated that for those parents that exhibit higher pressure to eat, parent stress was positively associated with adolescent z-BMI. CONCLUSIONS: These findings provide preliminary support suggesting that certain parenting practices interact with chronic stress on adolescent weight-related outcomes and that future interventions may consider integrating these factors.


Assuntos
Negro ou Afro-Americano , Poder Familiar , Adolescente , Índice de Massa Corporal , Comportamento Alimentar , Humanos , Relações Pais-Filho , Pais , Estresse Psicológico , Inquéritos e Questionários
15.
J Behav Med ; 44(4): 563-570, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33768390

RESUMO

This study evaluates whether parental provision of transportation for physical activity is associated with child/adolescent moderate-to-vigorous physical activity, while also evaluating community-level poverty. Self- and parental-reported surveys were administered with parents/caregivers and children in the Healthy Communities Study (N = 5138). Associations between individual-level demographics, community-level poverty, parental provision of transportation for physical activity, and moderate-to-vigorous physical activity were examined in multi-level models. Even when accounting for community-level poverty, which was significantly associated with lower moderate-to-vigorous physical activity, parental provision of transportation for physical activity was positively associated with greater moderate-to-vigorous physical activity. This study provides evidence for the importance of considering multiple systems of influence (e.g., community and individual factors) and considering how gaps in physical activity transportation for youth can be addressed in future health policies.


Assuntos
Exercício Físico , Pobreza , Adolescente , Criança , Humanos , Pais , Características de Residência , Inquéritos e Questionários , Meios de Transporte
16.
J Med Internet Res ; 23(4): e23488, 2021 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-33835930

RESUMO

BACKGROUND: A central component of the public health strategy to control the COVID-19 pandemic involves encouraging mask wearing and social distancing to protect individuals from acquiring and transmitting the virus. OBJECTIVE: This study aims to understand the psychological factors that drive adoption or rejection of these protective behaviors, which can inform public health interventions to control the pandemic. METHODS: We conducted an online survey of a representative sample of 1074 US adults and assessed three novel potential predictors of COVID-19 behaviors: trait reactance, COVID-19 conspiracy beliefs, and COVID-19 apocalypse beliefs. Key outcomes (dependent variables) included an index of COVID-19 protective behaviors, the number of trips taken from the home, and COVID-19 knowledge. RESULTS: In bivariate analyses, all three predictors were significantly correlated in the hypothesized direction with the three COVID-19 outcomes. Specifically, each predictor was negatively (P<.01) correlated with the COVID-19 protective behaviors index and COVID-19 knowledge score, and positively correlated with trips taken from home per week (more of which was considered higher risk). COVID-19 protective behaviors and COVID-19 knowledge were significantly lower in the top median compared to the bottom median for all three predictors. In general, these findings remained significant after adjusting for all novel predictors plus age, gender, income, education, race, political party, and religiosity. Self-identified Republicans (vs other political affiliations) reported the highest values for each of the novel predictors. CONCLUSIONS: This study can inform the development of health communication interventions to encourage the adoption of COVID-19 protective behaviors. Interestingly, we found that higher scores of all three novel predictors were associated with lower COVID-19 knowledge, suggesting that lack of an accurate understanding of the virus may be driving some of these attitudes; although, it is also possible that these attributes may interfere with one's willingness or ability to seek and absorb accurate health information. These individuals may be particularly immune to accepting new information and yielding their beliefs. Health communication professionals may apply lessons learned from countering similar beliefs around climate change and vaccine hesitancy. Messages designed for individuals prone to reactance may be more effective if they minimize controlling language and emphasize the individual's independence in adopting these behavioral recommendations. Messaging for those who possess conspiracy beliefs should similarly not assume that providing evidence contrary to these beliefs will alone alter behavior. Other communication techniques such as rolling with resistance, a strategy used in motivational interviewing, may be helpful. Messaging for those with apocalyptic beliefs may require using religious leaders as the message source and using scripture that would support the adoption of COVID-19 protection behaviors.


Assuntos
COVID-19/psicologia , Comportamentos Relacionados com a Saúde , Adolescente , Adulto , Idoso , COVID-19/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , SARS-CoV-2/isolamento & purificação , Inquéritos e Questionários , Estados Unidos/epidemiologia , Adulto Jovem
17.
Multivariate Behav Res ; 56(4): 543-557, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32525404

RESUMO

Latent class mediation modeling is designed to estimate the mediation effect when both the mediator and the outcome are latent class variables. We suggest using an adjusted one-step approach in which the latent class models for the mediator and the outcome are estimated first to decide on the number of classes, then the latent class models and the mediation model are jointly estimated. We present both an empirical demonstration and a simulation study to compare the performance of this one-step approach to a standard three-step approach with modal assignment (modal) and four different modern three-step approaches. Results from the study indicate that unadjusted modal, which ignores the classification errors of the latent class models, produced biased mediation effects. On the other hand, the adjusted one-step approach and the modern three-step approaches performed well with respect to bias for estimating mediation effects, regardless of measurement quality (i.e., model entropy) and latent class size. Among the three-step approaches we investigated, the maximum likelihood method with modal assignment and the BCH correction with robust standard error estimators are good alternatives to the adjusted one-step approach, given their unbiased standard error estimations.


Assuntos
Modelos Estatísticos , Viés , Simulação por Computador , Análise de Classes Latentes
18.
Sensors (Basel) ; 21(13)2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34282758

RESUMO

Electrical stimulation can be used to modulate activity within the nervous system in one of two modes: (1) Activation, where activity is added to the neural signalling pathways, or (2) Block, where activity in the nerve is reduced or eliminated. In principle, electrical nerve conduction block has many attractive properties compared to pharmaceutical or surgical interventions. These include reversibility, localization, and tunability for nerve caliber and type. However, methods to effect electrical nerve block are relatively new. Some methods can have associated drawbacks, such as the need for large currents, the production of irreversible chemical byproducts, and onset responses. These can lead to irreversible nerve damage or undesirable neural responses. In the present study we describe a novel low frequency alternating current blocking waveform (LFACb) and measure its efficacy to reversibly block the bradycardic effect elicited by vagal stimulation in anaesthetised rat model. The waveform is a sinusoidal, zero mean(charge balanced), current waveform presented at 1 Hz to bipolar electrodes. Standard pulse stimulation was delivered through Pt-Black coated PtIr bipolar hook electrodes to evoke bradycardia. The conditioning LFAC waveform was presented either through a set of CorTec® bipolar cuff electrodes with Amplicoat® coated Pt contacts, or a second set of Pt Black coated PtIr hook electrodes. The conditioning electrodes were placed caudal to the pulse stimulation hook electrodes. Block of bradycardic effect was assessed by quantifying changes in heart rate during the stimulation stages of LFAC alone, LFAC-and-vagal, and vagal alone. The LFAC achieved 86.2±11.1% and 84.3±4.6% block using hook (N = 7) and cuff (N = 5) electrodes, respectively, at current levels less than 110 µAp (current to peak). The potential across the LFAC delivering electrodes were continuously monitored to verify that the blocking effect was immediately reversed upon discontinuing the LFAC. Thus, LFACb produced a high degree of nerve block at current levels comparable to pulse stimulation amplitudes to activate nerves, resulting in a measurable functional change of a biomarker in the mammalian nervous system.


Assuntos
Bloqueio Nervoso , Condução Nervosa , Animais , Vias Autônomas , Estimulação Elétrica , Eletrodos , Ratos
19.
Health Promot Pract ; 22(6): 840-849, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-32639170

RESUMO

Background. The purpose of the current article is to demonstrate how formative process evaluation was used in a pilot study to optimize the design and implementation of two motivationally targeted community-based physical activity (PA) interventions for inactive African American women. Method. Fifteen African American women (M age: 41.6 years) were randomized to a challenge-focused program targeted toward high autonomous motivation or a rewards-focused program targeted toward low autonomous motivation. The challenge-focused program targeted enjoyment and valuation of PA and a team-based positive social climate through competitive intergroup activities and team-based goals, whereas the rewards-focused program targeted PA interest, competency, and partner-based social support through a walking program, individual-based goals with financial incentives, and partner-based action-plans. Results. Feedback from participants revealed high levels of acceptability of essential elements. Average weekly attendance exceeded the a priori goal of ≥75% of members in attendance each week. External systematic observation demonstrated that session content dose was ≥93% in both programs. Facilitator-level fidelity exceeded the a priori goal of averaging ≥3 on a 4-point scale for behavioral skills, communication, autonomy support, and session content. The process evaluation also revealed areas for improvement, including facilitator-level social support and behavioral skills at the group-level. Process data collected through FitBits revealed that participants were engaged in self-monitoring PA during the 6-week programs. Conclusions. The formative process evaluation demonstrated adequate levels of feasibility and acceptability and also provided key insights into adjustments needed before proceeding with implementing the motivationally targeted group-based programs in a larger randomized study.


Assuntos
Negro ou Afro-Americano , Motivação , Adulto , Exercício Físico , Estudos de Viabilidade , Feminino , Humanos , Projetos Piloto , Volição
20.
J Behav Med ; 43(3): 365-376, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32314136

RESUMO

Evidence suggests that physical activity and alcohol use are positively related among young adults. Two studies have examined daily relations, and results have shown conflicting findings. We examined relations between physical activity and alcohol use at both within- and between-individual levels and investigated moderators of the relation at both levels. 269 college students wore accelerometers to collect physical activity data over a 2-week period. At the end of each day, they indicated whether or not they drank alcohol. Multilevel logistic regression indicated neither within- nor between-subject relations were statistically significant. Positive affect, negative affect, and drinking motives moderated these relations at the between-subject level. Contrary to previous research, we did not observe a relation between physical activity and alcohol use at the daily level. Unique features of the current study suggest next steps for future research examining the perplexing PA-alcohol relation in this population.


Assuntos
Consumo de Bebidas Alcoólicas/epidemiologia , Exercício Físico , Adaptação Psicológica , Adolescente , Consumo de Bebidas Alcoólicas/psicologia , Feminino , Humanos , Masculino , Motivação , Estudantes , Universidades , Adulto Jovem
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