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1.
Dev Psychopathol ; : 1-14, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38934483

RESUMO

This study examines associations between early childhood attachment security and adolescent personality functioning in a high-risk sample within a developmental psychopathology framework. Data from 2,268 children (1165 male; 1103 female) and caregivers participating in Future of Families and Child Well-Being Study (FFCWS) were used to examine (1) effects of genetic polymorphisms of the serotonin transporter (5-HTTLPR) and dopamine D4 receptor (DRD4) genes and adverse childhood experiences (ACEs) on attachment security and emotional and behavioral dysregulation in early childhood and (2) longitudinal associations and transactional relationships among attachment security, dysregulation, negative parenting attitudes and behaviors, social competence, and adolescent personality functioning. Results revealed that ACEs predicted attachment security over and above sex or the genetic risk, and gene × environment interactions did not increment prediction. Results of cascade models showed that greater early childhood attachment security predicted higher adolescent level of personality functioning via pathways through intermediary variables. Limitations and future research directions are discussed.

3.
Percept Mot Skills ; 131(1): 135-160, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38253419

RESUMO

Typical visual perception includes an attention bias toward right hemisphere mediated global, holistic cortical processing. An atypically local, detail-oriented focus of attention is characteristic of left hemisphere processing and is often observed in patients whose field of attention is restricted by certain types of neurocognitive impairment. We designed the present pair of studies to induce a local attentional focus to observe its consequences on neurocognitive measures of visuospatial processing. In Experiment I, participants wore glasses mimicking simultanagnosia, a disorder of visual attention, to induce a narrowed, atypical attentional style while they completed visual neuropsychological tasks. This simulation impaired participants' capacities to visually synthesize and efficiently reproduce Complex Figure stimuli as measured with the Boston Qualitative Scoring System (BQSS), and it induced an atypical attentional style on Rorschach Performance Assessment System (R-PAS) responses. In Experiment II, participants wore glasses designed to provoke differential hemispheric activation, also hypothesized to influence style of visual attention; but this manipulation did not influence neurocognitive task performance. We discuss implications for the interpretation of BQSS and R-PAS scores and offer directions for future research.


Assuntos
Atenção , Percepção Visual , Humanos , Percepção Visual/fisiologia , Viés , Lateralidade Funcional/fisiologia
4.
Redox Biol ; 70: 103044, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38266577

RESUMO

Hyperglycemia increases the heart sensitivity to ischemia-reperfusion (IR), but the underlying cellular mechanisms remain unclear. Mitochondrial dynamics (the processes that govern mitochondrial morphology and their interactions with other organelles, such as the reticulum), has emerged as a key factor in the heart vulnerability to IR. However, it is unknown whether mitochondrial dynamics contributes to hyperglycemia deleterious effect during IR. We hypothesized that (i) the higher heart vulnerability to IR in hyperglycemic conditions could be explained by hyperglycemia effect on the complex interplay between mitochondrial dynamics, Ca2+ homeostasis, and reactive oxygen species (ROS) production; and (ii) the activation of DRP1, a key regulator of mitochondrial dynamics, could play a central role. Using transmission electron microscopy and proteomic analysis, we showed that the interactions between sarcoplasmic reticulum and mitochondria and mitochondrial fission were increased during IR in isolated rat hearts perfused with a hyperglycemic buffer compared with hearts perfused with a normoglycemic buffer. In isolated mitochondria and cardiomyocytes, hyperglycemia increased mitochondrial ROS production and Ca2+ uptake. This was associated with higher RyR2 instability. These results could contribute to explain the early mPTP activation in mitochondria from isolated hearts perfused with a hyperglycemic buffer and in hearts from streptozotocin-treated rats (to increase the blood glucose). DRP1 inhibition by Mdivi-1 during the hyperglycemic phase and before IR induction, normalized Ca2+ homeostasis, ROS production, mPTP activation, and reduced the heart sensitivity to IR in streptozotocin-treated rats. In conclusion, hyperglycemia-dependent DRP1 activation results in higher reticulum-mitochondria calcium exchange that contribute to the higher heart vulnerability to IR.


Assuntos
Dinaminas , Traumatismo por Reperfusão Miocárdica , Canal de Liberação de Cálcio do Receptor de Rianodina , Animais , Ratos , Cálcio/metabolismo , Doença da Artéria Coronariana/metabolismo , Hiperglicemia/metabolismo , Mitocôndrias Cardíacas/metabolismo , Dinâmica Mitocondrial , Traumatismo por Reperfusão Miocárdica/metabolismo , Proteômica , Espécies Reativas de Oxigênio/metabolismo , Reperfusão , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Estreptozocina/metabolismo , Estreptozocina/farmacologia , Dinaminas/metabolismo
6.
Nutrition ; 117: 112250, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37918311

RESUMO

OBJECTIVE: The aim of this study was to determine the development of sarcopenia in a COVID-19 intensive care unit population by sequential quadriceps and diaphragm ultrasound and its relationship with hospital outcomes. METHODS: We assessed muscle thickness, cross-sectional area, fascicle length, pennation angle, and echo intensity within 48 h after intubation, at days 5 and 10 and at discharge from the intensive care unit in 30 critically ill patients with confirmed COVID-19. RESULTS: A different evolution of muscle thickness of the diaphragm and m. rectus femoris was observed; the changes between the two muscles were not correlated (Pearson's χ2 3.91, P = 0.419). The difference in muscle thickness was linked to the outcome for both m. rectus femoris and diaphragm, with the best survival seen in the group with stable muscle thickness. The greatest loss of muscle thickness occurred between days 5 and 10. The echo intensity was higher in the patients with increased muscle thickness, who also had a worse prognosis. There was a correlation between cross-sectional area on day 5 and handgrip strength (r = 0.290, P = 0.010). Only 31% of patients were able to return to their preadmission residence without any additional rehabilitation. CONCLUSIONS: Muscle atrophy and decline in muscle strength appear in the earliest stages after admission to the intensive care unit and are related to functional outcome.


Assuntos
COVID-19 , Sarcopenia , Humanos , Estado Terminal/terapia , Diafragma/diagnóstico por imagem , Diafragma/patologia , Força da Mão , Unidades de Terapia Intensiva , Músculo Quadríceps/diagnóstico por imagem , Sarcopenia/diagnóstico por imagem , Sarcopenia/etiologia , Sarcopenia/patologia , Ultrassonografia
7.
Pediatr Crit Care Med ; 24(8): 652-661, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37092829

RESUMO

OBJECTIVES: Diaphragm ultrasound is a novel alternative to esophageal pressure measurements in the evaluation of diaphragm function and activity, but data about its reliability in a pediatric setting are lacking. We aimed to compare the esophageal pressure swing (∆P es , gold standard) with the diaphragmatic thickening fraction (DTF) as a measure of inspiratory effort in sedated children. Additionally, we studied the effect of positive end-expiratory pressure (PEEP) on the end-expiratory thickness of the diaphragm (DT ee ). DESIGN: Prospective open-label non-randomized interventional physiological cohort study. SETTING: Operating room in tertiary academic hospital. PATIENTS: Children 28 days to 13 years old scheduled for elective surgery with general anesthesia, spontaneously breathing through a laryngeal mask airway, were eligible for inclusion. Exclusion criteria were disorders or previous surgery of the diaphragm, anticipated difficult airway or acute cardiopulmonary disease. All measurements were performed prior to surgery. INTERVENTIONS: Patients were subjected to different levels of respiratory load, PEEP and anesthetic depth in a total of seven respiratory conditions. MEASUREMENTS AND MAIN RESULTS: The esophageal pressure and diaphragm thickening fraction were simultaneously recorded for five breaths at each respiratory condition. The relation between ∆P es and DTF was studied in a mixed model. We analyzed 407 breaths in 13 patients. Both DTF ( p = 0.03) and ∆Pes ( p = 0.002) could detect respiratory activity, and ∆P es and DTF were associated across respiratory conditions ( p < 0.001; R2 = 31%). With increasing inspiratory load, ∆P es increased significantly, while DTF did not ( p = 0.08). Additionally, DT ee did not differ significantly between 10, 5, and 0 cm H 2 O PEEP ( p = 0.08). CONCLUSIONS: In spontaneously breathing sedated children and across different respiratory conditions, DTF could differentiate minimal or no inspiratory effort from substantial inspiratory effort and was associated with ∆P es . Increased efforts resulted in higher ∆P es but not larger DTF.


Assuntos
Diafragma , Respiração Artificial , Humanos , Criança , Diafragma/diagnóstico por imagem , Estudos Prospectivos , Estudos de Viabilidade , Reprodutibilidade dos Testes , Estudos de Coortes , Respiração Artificial/métodos
8.
Anesth Analg ; 137(4): 841-849, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-36729514

RESUMO

BACKGROUND: Increased intra-abdominal pressure during laparoscopy induces atelectasis. Positive end-expiratory pressure (PEEP) can alleviate atelectasis but may cause hyperinflation. Cyclic opening of collapsed alveoli and hyperinflation can lead to ventilator-induced lung injury and postoperative pulmonary complications. We aimed to study the effect of PEEP on atelectasis, lung stress, and hyperinflation during laparoscopy in the head-down (Trendelenburg) position. METHODS: An open-label, repeated-measures, interventional, physiological cohort trial was designed. All participants were recruited from a single tertiary Belgian university hospital. Twenty-three nonobese patients scheduled for laparoscopy in the Trendelenburg position were recruited.We applied a decremental PEEP protocol: 15 (high), 10 and 5 (low) cm H 2 O. Atelectasis was studied with the lung ultrasound score, the end-expiratory transpulmonary pressure, the arterial oxygen partial pressure to fraction of inspired oxygen concentration (P ao2 /Fi o2 ) ratio, and the dynamic respiratory system compliance. Global hyperinflation was evaluated by dead space volume, and regional ventilation was evaluated by lung ultrasound. Lung stress was estimated using the transpulmonary driving pressure and dynamic compliance. Data are reported as medians (25th-75th percentile). RESULTS: At 15, 10, and 5 cm H 2 O PEEP, the respective measurements were: lung ultrasound scores (%) 11 (0-22), 27 (11-39), and 53 (42-61) ( P < .001); end-expiratory transpulmonary pressures (cm H 2 O) 0.9 (-0.6 to 1.7), -0.3 (-2.0 to 0.7), and -1.9 (-4.6 to -0.9) ( P < .001); P ao2 /Fi o2 ratios (mm Hg) 471 (435-538), 458 (410-537), and 431 (358-492) ( P < .001); dynamic respiratory system compliances (mL/cm H 2 O) 32 (26-36), 30 (25-34), and 27 (22-30) ( P < .001); driving pressures (cm H 2 O) 8.2 (7.5-9.5), 9.3 (8.5-11.1), and 11.0 (10.3-12.2) ( P < .001); and alveolar dead space ventilation fractions (%) 10 (9-12), 10 (9-12), and 9 (8-12) ( P = .23). The lung ultrasound score was similar between apical and basal lung regions at each PEEP level ( P = .76, .37, and .76, respectively). CONCLUSIONS: Higher PEEP levels during laparoscopy in the head-down position facilitate lung-protective ventilation. Atelectasis and lung stress are reduced in the absence of global alveolar hyperinflation.


Assuntos
Laparoscopia , Atelectasia Pulmonar , Lesão Pulmonar Induzida por Ventilação Mecânica , Humanos , Estudos de Coortes , Decúbito Inclinado com Rebaixamento da Cabeça , Laparoscopia/efeitos adversos , Oxigênio , Atelectasia Pulmonar/diagnóstico por imagem , Atelectasia Pulmonar/etiologia , Atelectasia Pulmonar/prevenção & controle , Volume de Ventilação Pulmonar
9.
Nutrients ; 15(1)2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36615872

RESUMO

Hyperglycemia (HG) is associated with increased mortality and morbidity in acute ischemic events. Regardless of the tissue or organs involved, the vascular endothelium is a key target of ischemia-reperfusion (I/R) injury severity. Among endothelium-protective strategies, exercise has been widely described as useful. However, whether this strategy is able to impact the deleterious effect of HG on endothelial function during I/R has never been challenged. For this, 48 male Wistar rats were randomized into 4 groups: sedentary (Sed) or exercised (Ex, 45 min/day, 5 days/week for 5 weeks) rats, treated (hyperglycemic, HG) or not (normoglycemic, NG) with streptozotocin (40 mg/kg, 48 h before procedure). Vascular I/R (120/15 min) was performed by clamping the femoral artery. Arterial and downstream muscular perfusions were assessed using laser speckle contrast imaging. Vascular endothelial function was assessed in vivo 15 min after reperfusion. HG was responsible for impairment of reperfusion blood flow as well as endothelial function. Interestingly exercise was able to prevent those impairments in the HG group. In agreement with the previous results, HG increased reactive oxygen species production and decreased nitric oxide bioavailability whereas exercise training normalized these parameters. It, therefore, appears that exercise may be an effective prevention strategy against the exacerbation of vascular and muscular damage by hyperglycemia during I/R.


Assuntos
Hiperglicemia , Traumatismo por Reperfusão , Ratos , Masculino , Animais , Ratos Wistar , Isquemia/complicações , Traumatismo por Reperfusão/prevenção & controle , Traumatismo por Reperfusão/complicações , Reperfusão , Endotélio Vascular
10.
Assessment ; 30(8): 2417-2432, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-36658765

RESUMO

Building on the comparative nonpatient study of Pianowski et al., we examine data from the Rorschach Performance Assessment System (R-PAS) and Comprehensive System (CS) in 100 nonpatients and 100 patients, 50 of each per system. Replicating their results but now in a patient sample, R-PAS produced more patient protocols having an optimal number of responses (R) for interpretation and eliminated the need for readministration due to low R. The R-PAS protocols were also much less variable in R, despite having about 2.5 more responses. Extending their results, we document that the primary markers of psychopathology in each system validly differentiate patients from nonpatients. However, R-PAS produced stronger effects. Finally, Complexity added to the valid discrimination of patients from nonpatients just for R-PAS, with patients producing less complex and rich records. The more erratic variability in R for the CS produced larger Complexity standard deviations (SDs) that obscured these genuine differences in people. We discuss implications for research and applied practice, along with directions for future research.


Assuntos
Teste de Rorschach , Humanos , Psicometria , Reprodutibilidade dos Testes , Psicopatologia , Pacientes
11.
Intensive Care Med Exp ; 10(1): 19, 2022 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-35608696

RESUMO

BACKGROUND: Flow-controlled ventilation (FCV), a novel mode of mechanical ventilation characterised by constant flow during active expiration, may result in more efficient alveolar gas exchange, better lung recruitment and might be useful in limiting ventilator-induced lung injury. However, data regarding FCV in mechanically ventilated patients with acute lung injury or acute respiratory distress syndrome (ARDS) are scarce. OBJECTIVES: We hypothesised that the use of FCV is feasible and would improve oxygenation in moderate COVID-19 ARDS compared to conventional ventilation. DESIGN: Open-label repeated-measures controlled trial. SETTING: From February to April 2021, patients with moderate COVID-19 ARDS were recruited in a tertiary referral intensive care unit. PATIENTS: Patients with moderate ARDS (PaO2/FIO2 ratio 100-200 mmHg, SpO2 88-94% and PaO2 60-80 mmHg) were considered eligible. Exclusion criteria were: extremes of age (< 18 years, > 80 years), obesity (body mass index > 40 kg/m2), prone positioning at the time of intervention, mechanical ventilation for more than 10 days and extracorporeal membrane oxygenation. Eleven patients were recruited. INTERVENTION: Participants were ventilated in FCV mode for 30 min, and subsequently in volume-control mode (VCV) for 30 min. MAIN OUTCOME MEASURES: Feasibility of FCV to maintain oxygenation was assessed by the PaO2/FiO2 ratio (mmHg) as a primary outcome parameter. Secondary outcomes included ventilator parameters, PaCO2 and haemodynamic data. All adverse events were recorded. RESULTS: FCV was feasible in all patients and no adverse events were observed. There was no difference in the PaO2/FIO2 ratio after 30 min of ventilation in FCV mode (169 mmHg) compared to 30 min of ventilation in VCV mode subsequently (168 mmHg, 95% CI of pseudo-medians (- 10.5, 3.6), p = 0.56). The tidal volumes (p < 0.01) and minute ventilation were lower during FCV (p = 0.01) while PaCO2 was similar at the end of the 30-min ventilation periods (p = 0.31). Mean arterial pressure during FCV was comparable to baseline. CONCLUSIONS: Thirty minutes of FCV in patients with moderate COVID-19 ARDS receiving neuromuscular blocking agents resulted in similar oxygenation, compared to VCV. FCV was feasible and did not result in adverse events. TRIAL REGISTRATION: Clinicaltrials.gov identifier: NCT04894214.

12.
Front Psychol ; 13: 735934, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35401320

RESUMO

The study of the relationship between reasoning and emotional processes is not new in Psychology. There are currently two main approaches to understanding the aspects related to these processes called emotional intelligence: the ability model and the trait model. This study focuses on the latter, analyzing the factor structure, reliability, and validity of the Trait Emotional Intelligence Questionnaire (TEIQue) in a Brazilian sample. 4314 adults with ages ranging from 18 to 60 years (M = 30.37; SD = 9.73) answered the TEIQue and other online instruments measuring emotional regulation, impulsiveness, alexithymia, loneliness, quality of life, positive and negative affect, personality traits, emotional perception, emotional understanding, and reasoning tests. The original four-factor structure of the TEIQue was replicated, Cronbach's alphas ranged from 0.60 to 0.89 for the facets, and from 0.76 to 0.90 for the factors and global score. The correlations followed theoretically expected directions, showing a stronger pattern for self-report measures than for performance tasks. Our results corroborated previous studies with the TEIQue, confirming the psychometric adequacy of the instrument in the Brazilian context. Future studies may focus on participants with lower levels of education and additional external criteria, such as career preferences, job performance, and health.

13.
Psychol Inj Law ; : 1-17, 2022 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-35308458

RESUMO

The ongoing COVID-19 pandemic has required psychologists to adopt measures like physical distancing and mask wearing, though other safety procedures such as travel restrictions or prohibitions on in-person practice and research have fostered the use of tele-health tools. In this article, we review options for using the Rorschach task via videoconference and provide preliminary data from using a new electronic app for remote R-PAS administration to determine whether the remote administration in an electronic form yields different information than in-person administration with the cards in hand. As a pilot study, our focus is on the "first factor" of all Rorschach scores, i.e., complexity. Data were collected from 60 adult Italian community volunteers, and statistical analyses evaluated the extent to which the average complexity score significantly departed from R-PAS normative expectations (SS = 100), accompanied by Bayesian likelihoods for supporting the null hypothesis. Results suggest that the general level of complexity shown by the test-takers when administered the Rorschach remotely with the new R-PAS app closely resembles that previously observed using "standard" in-person procedures. Tentative analyses of other R-PAS scores suggested normative departures that could be due to the effects of the app, testing at home, or responses to the pandemic. We offer recommendations for future research and discuss practical implications.

14.
J Pers Assess ; 104(2): 137-161, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35180040

RESUMO

The special issue editors selected us to form an "adversarial collaboration" because our publications and teaching encompass both supportive and critical attitudes toward the Rorschach and its recently developed system for use, the Rorschach Performance Assessment System (R-PAS). We reviewed the research literature and case law to determine if the Rorschach and specifically R-PAS meet legal standards for admissibility in court. We included evidence on norms, reliability, validity, utility, general acceptance, forensic evaluator use, and response style assessment, as well as United States and selected European case law addressing challenges to mental examination motions, admissibility, and weight. Compared to other psychological tests, the Rorschach is not challenged at unusually high rates. Although the recently introduced R-PAS is not widely referenced in case law, evidence suggests that information from it is likely to be ruled admissible when used by a competent evaluator and selected variables yield scores that are sufficiently reliable and valid to evaluate psychological processes that inform functional psycholegal capacities. We identify effective and ethical but also inappropriate uses (e.g., psychological profiling) of R-PAS in criminal, civil, juvenile, and family court. We recommend specific research to clarify important aspects of R-PAS and advance its utility in forensic mental health assessment.


Assuntos
Criminosos , Humanos , Testes Psicológicos , Reprodutibilidade dos Testes , Estados Unidos
15.
Assessment ; 29(5): 859-871, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-33218260

RESUMO

We examine interrater reliability for scoring the Rorschach Performance Assessment System (R-PAS) in a sample of 89 adolescents (MAge = 13.2, SD = 1.01) from Brazil using exact agreement intraclass correlations coefficient (ICCs) for the 60 protocol-level scores that are the focus of interpretation. The first author completed or reviewed all of the primary coding, and seven R-PAS proficient psychologists trained at different sites independently produced secondary coding. Overall, excellent agreement was found (M ICC = 0.89; SD = 0.09). When averaged across this study and three other comparison studies, stronger reliability was present, in general, for commonly coded variables (M = 0.87) as opposed to rare or infrequent variables (M = 0.78). In addition, 78.3% of the variables showed excellent interrater reliability and an additional 20.0% had good reliability. The results also showed that the ICCs for most variables had low variability across studies, suggesting clear coding guidelines. However, variables with higher ICC variability across studies indicated domains where it would be desirable to expand guidelines with more detailed parameters. Overall, the findings indicate excellent interrater reliability for the great majority of codes and present solid grounds for future research on interrater reliability with R-PAS.


Assuntos
Teste de Rorschach , Adolescente , Brasil , Humanos , Variações Dependentes do Observador , Reprodutibilidade dos Testes
16.
Acta Chir Belg ; 122(5): 312-320, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33150853

RESUMO

BACKGROUND: Postoperative cardio-surgical haemostatic management is centre-specific and experience-based, which leads to a variability in patient care. This study aimed to identify which postoperative haemostatic interventions may reduce the need for reoperation after cardiac surgery in adults. METHODS: A retrospective case-control study in a tertiary centre. Adult, elective, primary cardiac surgical patients were selected (n = 2098); cases (n = 42) were patients who underwent reoperation within 72 h after the initial surgery. Interventions administered to control surgical bleeding were compared for the need to re-operate using multiple logistic regression. RESULTS: Rate of cardiac surgical reoperation was 2% in the study population. Three variables were found to be associated with cardiac reoperation: preoperative administration of fresh frozen plasma (OR 5.45, CI 2.34-12.35), cumulative volume of chest tube drainage and cumulative count of packed red blood cells transfusion on ICU (OR 1.98, CI 1.56-2.51). CONCLUSION: No significant difference among specific types of postoperative haemostatic interventions was found between patients who needed reoperation and those who did not. Perioperative transfusion of fresh frozen plasma, postoperative transfusion of packed cells and cumulative volume of chest tube drainage were associated with reoperation after cardiac surgery. These variables could help predict the need for reoperation.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Hemostáticos , Adulto , Perda Sanguínea Cirúrgica , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Estudos de Casos e Controles , Humanos , Reoperação , Estudos Retrospectivos
17.
Basic Res Cardiol ; 116(1): 66, 2021 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-34940922

RESUMO

Endothelial nitric oxide synthase (eNOS) activation in the heart plays a key role in exercise-induced cardioprotection during ischemia-reperfusion, but the underlying mechanisms remain unknown. We hypothesized that the cardioprotective effect of exercise training could be explained by the re-localization of eNOS-dependent nitric oxide (NO)/S-nitrosylation signaling to mitochondria. By comparing exercised (5 days/week for 5 weeks) and sedentary Wistar rats, we found that exercise training increased eNOS level and activation by phosphorylation (at serine 1177) in mitochondria, but not in the cytosolic subfraction of cardiomyocytes. Using confocal microscopy, we confirmed that NO production in mitochondria was increased in response to H2O2 exposure in cardiomyocytes from exercised but not sedentary rats. Moreover, by S-nitrosoproteomic analysis, we identified several key S-nitrosylated proteins involved in mitochondrial function and cardioprotection. In agreement, we also observed that the increase in Ca2+ retention capacity by mitochondria isolated from the heart of exercised rats was abolished by exposure to the NOS inhibitor L-NAME or to the reducing agent ascorbate, known to denitrosylate proteins. Pre-incubation with ascorbate or L-NAME also increased mitochondrial reactive oxygen species production in cardiomyocytes from exercised but not from sedentary animals. We confirmed these results using isolated hearts perfused with L-NAME before ischemia-reperfusion. Altogether, these results strongly support the hypothesis that exercise training increases eNOS/NO/S-nitrosylation signaling in mitochondria, which might represent a key mechanism of exercise-induced cardioprotection.


Assuntos
Peróxido de Hidrogênio , Proteína S , Animais , Mitocôndrias , Miócitos Cardíacos , Óxido Nítrico , Óxido Nítrico Sintase Tipo III , Ratos , Ratos Wistar
18.
Phys Rev Lett ; 126(3): 030602, 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33543957

RESUMO

Many-body chaos has emerged as a powerful framework for understanding thermalization in strongly interacting quantum systems. While recent analytic advances have sharpened our intuition for many-body chaos in certain large N theories, it has proven challenging to develop precise numerical tools capable of exploring this phenomenon in generic Hamiltonians. To this end, we utilize massively parallel, matrix-free Krylov subspace methods to calculate dynamical correlators in the Sachdev-Ye-Kitaev model for up to N=60 Majorana fermions. We begin by showing that numerical results for two-point correlation functions agree at high temperatures with dynamical mean field solutions, while at low temperatures finite-size corrections are quantitatively reproduced by the exactly solvable dynamics of near extremal black holes. Motivated by these results, we develop a novel finite-size rescaling procedure for analyzing the growth of out-of-time-order correlators. Our procedure accurately determines the Lyapunov exponent, λ, across a wide range in temperatures, including in the regime where λ approaches the universal bound, λ=2π/ß.

19.
Adv Nutr ; 12(4): 1500-1513, 2021 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-33578411

RESUMO

The excess consumption of added sugar is consistently found to be associated with weight gain, and a higher risk of type 2 diabetes mellitus, coronary heart disease, and stroke. In an effort to reduce the risk of cardiometabolic disease, sugar is frequently replaced by low- and null-calorie sweeteners (LCSs). Alarmingly, though, emerging evidence indicates that the consumption of LCSs is associated with an increase in cardiovascular mortality risk that is amplified in those who are overweight or obese. Sucralose, a null-caloric high-intensity sweetener, is the most commonly used LCS worldwide, which is regularly consumed by healthy individuals and patients with metabolic disease. To explore a potential causal role for sucralose in increased cardiovascular risk, this present review summarizes the preclinical and clinical data from current research detailing the effects of sucralose on systems controlling food intake, glucose homeostasis, and gut microbiota.


Assuntos
Doenças Cardiovasculares , Diabetes Mellitus Tipo 2 , Adoçantes não Calóricos , Humanos , Adoçantes não Calóricos/efeitos adversos , Sacarose/análogos & derivados
20.
Mol Nutr Food Res ; 65(6): e2000487, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33450108

RESUMO

SCOPE: A main risk factor of atherosclerosis is a Western diet (WD) rich in n-6 polyunsaturated fatty acids (PUFAs) sensitive to oxidation. Their oxidation can be initiated by heme iron of red meat leading to the formation of 4-hydroxy-2-nonenal (4-HNE), a cytotoxic aldehyde. An increased 4-HNE production is implicated in endothelial dysfunction and atherosclerosis. By contrast, a diet rich in proanthocyanidins reduces oxidative stress and arterial diseases. This study evaluates the effects of a WD on vascular integrity in ApolipoproteinE (ApoE-/- ) mice and the protective capacity of apple extract and puree rich in antioxidant proanthocyanidins. METHODS AND RESULTS: ApoE-/- mice are fed during 12 weeks with a WD with or without n-6 PUFAs. Moreover, two WD + n-6 PUFAs groups are supplemented with apple puree or phenolic extract. An increase in digestive 4-HNE production associated with a rise in plasmatic 4-HNE and oxidized LDL concentrations is reported. Oxidizable n-6 PUFAs consumption is associated with a worsened endothelial dysfunction and atherosclerosis. Interestingly, supplementations with apple polyphenol extract or puree prevented these impairments while reducing oxidative stress. CONCLUSION: n-6 lipid oxidation during digestion may be a key factor of vascular impairments. Nevertheless, an antioxidant strategy can limit 4-HNE formation during digestion and thus durably protect vascular function.


Assuntos
Aterosclerose/prevenção & controle , Aterosclerose/fisiopatologia , Dieta Ocidental/efeitos adversos , Ácidos Graxos Ômega-6/farmacocinética , Malus/química , Polifenóis/farmacologia , Aldeídos/análise , Aldeídos/metabolismo , Animais , Aterosclerose/etiologia , Suplementos Nutricionais , Ácidos Graxos Ômega-6/metabolismo , Lipoproteínas LDL/sangue , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout para ApoE , Óxido Nítrico/metabolismo , Oxirredução , Placa Aterosclerótica/diagnóstico por imagem , Placa Aterosclerótica/prevenção & controle , Polifenóis/química , Espécies Reativas de Oxigênio/metabolismo
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