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1.
Am J Clin Nutr ; 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38452857

RESUMO

BACKGROUND: Heat treatments of dairy, including pasteurization and ultra-high temperature (UHT) processing, alter milk macromolecular structures, and ultimately affect digestion. In vitro, animal, and human studies show faster nutrient release or circulating appearance after consuming UHT milk (UHT-M) compared with pasteurized milk (PAST-M), with a faster gastric emptying (GE) rate proposed as a possible mechanism. OBJECTIVES: To investigate the impact of milk heat treatment on GE as a mechanism of faster nutrient appearance in blood. We hypothesized that GE and circulating nutrient delivery following consumption would be faster for UHT-M than PAST-M. METHODS: In this double-blind randomized controlled cross-over trial, healthy female (n = 20; 27.3 ± 1.4 y, mean ± SD) habitual dairy consumers, consumed 500 mL of either homogenized bovine UHT-M or PAST-M (1340 compared with 1320 kJ). Gastric content volume (GCV) emptying half-time (T50) was assessed over 3 h by magnetic resonance imaging subjective digestive symptoms, plasma amino acid, lipid and B vitamin concentrations, and gastric myoelectrical activity were measured over 5 h. RESULTS: Although GCV T50 did not differ (102 ± 7 min compared with 89 ± 8 min, mean ± SEM, UHT-M and PAST-M, respectively; P = 0.051), GCV time to emptying 25% of the volume was 31% longer following UHT-M compared with PAST-M (42 ± 2 compared with 32 ± 4 min, P = 0.004). Although GCV remained larger for a longer duration following UHT-M (treatment × time interaction, P = 0.002), plasma essential amino acid AUC was greater following UHT-M than PAST-M (55,324 ± 3809 compared with 36,598 ± 5673 µmol·min·L-1, P = 0.006). Heat treatment did not impact gastric myoelectrical activity, plasma appetite hormone markers or subjective appetite scores. CONCLUSIONS: Contrary to expectations, GE was slower with UHT-M, yet, as anticipated, aminoacidemia was greater. The larger GCV following UHT-M suggests that gastric volume may poorly predict circulating nutrient appearance from complex food matrices. Dairy heat treatment may be an effective tool to modify nutrient release by impacting digestion kinetics. CLINICAL TRIAL REGISTRY: www.anzctr.org.au (ACTRN12620000172909).

2.
Eur J Appl Physiol ; 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38386104

RESUMO

PURPOSE: Intestinal permeability is a critical component of gut barrier function. Barrier dysfunction can be triggered by certain stressors such as exercise, and if left unmanaged can lead to local and systemic disorders. The aim of this study was to investigate the effects of a specific whey protein fraction in alleviating exercise-induced gut permeability as assessed by recovery of lactulose/rhamnose (L/R) and lactulose/mannitol (L/M) urinary probes. METHODS: Eight males and eight females (aged 18-50) completed two arms of a double-blind, placebo-controlled, crossover study. For each arm participants performed two baseline intestinal permeability assessments, following which they consumed the treatment (2 g/day of milk powder containing 200 mg of whey protein) or placebo (2 g/day of milk powder) for 14 days, before performing a post-exercise permeability assessment. The exercise protocol involved a 20-min run at 80% of maximal oxygen uptake on a 1% incline. RESULTS: Mixed model analysis revealed an increase in L/R (23%; P < 0.001) and L/M (20%; P < 0.01) recovery following exercise. However, there was no treatment or treatment × exercise effect. CONCLUSION: The exercise protocol utilised in our study induces gut permeability. However, consuming whey protein, at the dose and timing prescribed, is not able to mitigate this effect.

3.
J Am Heart Assoc ; 13(3): e029427, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38293915

RESUMO

BACKGROUND: The right ventricle (RV) is at risk in patients with complex congenital heart disease involving right-sided obstructive lesions. We have shown that capillary rarefaction occurs early in the pressure-loaded RV. Here we test the hypothesis that microRNA (miR)-34a, which is induced in RV hypertrophy and RV failure (RVF), blocks the hypoxia-inducible factor-1α-vascular endothelial growth factor (VEGF) axis, leading to the attenuated angiogenic response and increased susceptibility to RV failure. METHODS AND RESULTS: Mice underwent pulmonary artery banding to induce RV hypertrophy and RVF. Capillary rarefaction occurred immediately. Although hypoxia-inducible factor-1α expression increased (0.12±0.01 versus 0.22±0.03, P=0.05), VEGF expression decreased (0.61±0.03 versus 0.22±0.05, P=0.01). miR-34a expression was most upregulated in fibroblasts (4-fold), but also in cardiomyocytes and endothelial cells (2-fold). Overexpression of miR-34a in endothelial cells increased cell senescence (10±3% versus 22±2%, P<0.05) by suppressing sirtulin 1 expression, and decreased tube formation by 50% via suppression of hypoxia-inducible factor-1α, VEGF A, VEGF B, and VEGF receptor 2. miR-34a was induced by stretch, transforming growth factor-ß1, adrenergic stimulation, and hypoxia in cardiac fibroblasts and cardiomyocytes. In mice with RVF, locked nucleic acid-antimiR-34a improved RV shortening fraction and survival half-time and restored capillarity and VEGF expression. In children with congenital heart disease-related RVF, RV capillarity was decreased and miR-34a increased 5-fold. CONCLUSIONS: In summary, miR-34a from fibroblasts, cardiomyocytes, and endothelial cells mediates capillary rarefaction by suppressing the hypoxia-inducible factor-1α-VEGF axis in RV hypertrophy/RVF, raising the potential for anti-miR-34a therapeutics in patients with at-risk RVs.


Assuntos
Cardiopatias Congênitas , Insuficiência Cardíaca , MicroRNAs , Rarefação Microvascular , Criança , Humanos , Camundongos , Animais , Fator A de Crescimento do Endotélio Vascular/metabolismo , Células Endoteliais/metabolismo , 60489 , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Rarefação Microvascular/metabolismo , Insuficiência Cardíaca/metabolismo , Hipertrofia Ventricular Direita , Miócitos Cardíacos/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Cardiopatias Congênitas/metabolismo
6.
Heart ; 110(9): 666-674, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38148157

RESUMO

OBJECTIVE: Variants in the FLNA gene have been associated with mitral valve dystrophy (MVD), and even polyvalvular disease has been reported. This study aimed to analyse the aortic valve and root involvement in FLNA-MVD families and its impact on outcomes. METHODS: 262 subjects (37 (18-53) years, 140 male, 79 carriers: FLNA+) from 4 FLNA-MVD families were included. Echocardiography was performed in 185 patients and histological analysis in 3 explanted aortic valves. The outcomes were defined as aortic valve surgery or all-cause mortality. RESULTS: Aortic valve alterations were found in 58% of FLNA+ compared with 6% of FLNA- (p<0.001). 9 (13.4%) FLNA+ had bicuspid aortic valve compared with 4 (3.4%) FLNA- (p=0.03). Overall, the transvalvular mean gradient was slightly increased in FLNA+ (4.8 (4.1-6.1) vs 4.0 (2.9-4.9) mm Hg, p=0.02). The sinuses of Valsalva and sinotubular junction diameters were enlarged in FLNA+ subjects (all p<0.05). 8 FLNA+ patients underwent aortic valve surgery (0 in relatives; p<0.001). Myxomatous remodelling with an infiltration of immune cells was observed. Overall survival was similar between FLNA+ versus FLNA- subjects (86±5% vs 85±6%, p=0.36). There was no statistical evidence for an interaction between genetic status and sex (p=0.15), but the survival tended to be impaired in FLNA+ men (p=0.06) whereas not in women (p=0.71). CONCLUSION: The patients with FLNA variants present frequent aortic valve disease and worse outcomes. Bicuspid aortic valve is more frequent in patients carrying the FLNA-MVD variants. These unique features should be factored into the management of patients with dystrophic and/or bicuspid aortic valve.


Assuntos
Estenose da Valva Aórtica , Doença da Válvula Aórtica Bicúspide , Doenças das Valvas Cardíacas , Cardiopatia Reumática , Humanos , Masculino , Feminino , Filaminas/genética , Doenças das Valvas Cardíacas/diagnóstico por imagem , Doenças das Valvas Cardíacas/genética , Doenças das Valvas Cardíacas/cirurgia , Aorta/patologia , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Valva Aórtica/patologia , Estenose da Valva Aórtica/cirurgia , Estudos Retrospectivos
7.
bioRxiv ; 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37961228

RESUMO

Cardiovascular diseases are a leading cause of death worldwide, but our understanding of the underlying mechanisms is limited, in part because of the complexity of the cellular machinery that controls the heart muscle contraction cycle. Cryogenic electron tomography (cryo-ET) provides a way to visualize diverse cellular machinery while preserving contextual information like subcellular localization and transient complex formation, but this approach has not been widely applied to the study of heart muscle cells (cardiomyocytes). Here, we deploy a platform for studying cardiovascular disease by combining cryo-ET with human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs). After developing a cryo-ET workflow for visualizing macromolecules in hiPSC-CMs, we reconstructed sub-nanometer resolution structures of the human thin filament, a central component of the contractile machinery. We also visualized a previously unobserved organization of a regulatory complex that connects muscle contraction to calcium signaling (the troponin complex), highlighting the value of our approach for interrogating the structures of cardiac proteins in their cellular context.

8.
Circulation ; 148(21): 1691-1704, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37850394

RESUMO

BACKGROUND: Hypercontractility and arrhythmia are key pathophysiologic features of hypertrophic cardiomyopathy (HCM), the most common inherited heart disease. ß-Adrenergic receptor antagonists (ß-blockers) are the first-line therapy for HCM. However, ß-blockers commonly selected for this disease are often poorly tolerated in patients, where heart-rate reduction and noncardiac effects can lead to reduced cardiac output and fatigue. Mavacamten, myosin ATPase inhibitor recently approved by the US Food and Drug Administration, has demonstrated the ability to ameliorate hypercontractility without lowering heart rate, but its benefits are so far limited to patients with left ventricular (LV) outflow tract obstruction, and its effect on arrhythmia is unknown. METHODS: We screened 21 ß-blockers for their impact on myocyte contractility and evaluated the antiarrhythmic properties of the most promising drug in a ventricular myocyte arrhythmia model. We then examined its in vivo effect on LV function by hemodynamic pressure-volume loop analysis. The efficacy of the drug was tested in vitro and in vivo compared with current therapeutic options (metoprolol, verapamil, and mavacamten) for HCM in an established mouse model of HCM (Myh6R403Q/+ and induced pluripotent stem cell (iPSC)-derived cardiomyocytes from patients with HCM (MYH7R403Q/+). RESULTS: We identified that carvedilol, a ß-blocker not commonly used in HCM, suppresses contractile function and arrhythmia by inhibiting RyR2 (ryanodine receptor type 2). Unlike metoprolol (a ß1-blocker), carvedilol markedly reduced LV contractility through RyR2 inhibition, while maintaining stroke volume through α1-adrenergic receptor inhibition in vivo. Clinically available carvedilol is a racemic mixture, and the R-enantiomer, devoid of ß-blocking effect, retains the ability to inhibit both α1-receptor and RyR2, thereby suppressing contractile function and arrhythmias without lowering heart rate and cardiac output. In Myh6R403Q/+ mice, R-carvedilol normalized hyperdynamic contraction, suppressed arrhythmia, and increased cardiac output better than metoprolol, verapamil, and mavacamten. The ability of R-carvedilol to suppress contractile function was well retained in MYH7R403Q/+ iPSC-derived cardiomyocytes. CONCLUSIONS: R-enantiomer carvedilol attenuates hyperdynamic contraction, suppresses arrhythmia, and at the same time, improves cardiac output without lowering heart rate by dual blockade of α1-adrenergic receptor and RyR2 in mouse and human models of HCM. This combination of therapeutic effects is unique among current therapeutic options for HCM and may particularly benefit patients without LV outflow tract obstruction.


Assuntos
Cardiomiopatia Hipertrófica , Metoprolol , Humanos , Camundongos , Animais , Carvedilol/farmacologia , Carvedilol/uso terapêutico , Metoprolol/uso terapêutico , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Cardiomiopatia Hipertrófica/complicações , Cardiomiopatia Hipertrófica/tratamento farmacológico , Arritmias Cardíacas/tratamento farmacológico , Arritmias Cardíacas/metabolismo , Antagonistas Adrenérgicos beta/farmacologia , Antagonistas Adrenérgicos beta/uso terapêutico , Miócitos Cardíacos/metabolismo , Verapamil/uso terapêutico , Receptores Adrenérgicos/metabolismo
10.
Commun Med (Lond) ; 3(1): 127, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37758840

RESUMO

BACKGROUND: Recent large-scale sequencing efforts have shed light on the genetic contribution to the etiology of congenital heart defects (CHD); however, the relative impact of genetics on clinical outcomes remains less understood. Outcomes analyses using genetics are complicated by the intrinsic severity of the CHD lesion and interactions with conditionally dependent clinical variables. METHODS: Bayesian Networks were applied to describe the intertwined relationships between clinical variables, demography, and genetics in a cohort of children with single ventricle CHD. RESULTS: As isolated variables, a damaging genetic variant in a gene related to abnormal heart morphology and prolonged ventilator support following stage I palliative surgery increase the probability of having a low Mental Developmental Index (MDI) score at 14 months of age by 1.9- and 5.8-fold, respectively. However, in combination, these variables act synergistically to further increase the probability of a low MDI score by 10-fold. The absence of a damaging variant in a known syndromic CHD gene and a shorter post-operative ventilator support increase the probability of a normal MDI score 1.7- and 2.4-fold, respectively, but in combination increase the probability of a good outcome by 59-fold. CONCLUSIONS: Our analyses suggest a modest genetic contribution to neurodevelopmental outcomes as isolated variables, similar to known clinical predictors. By contrast, genetic, demographic, and clinical variables interact synergistically to markedly impact clinical outcomes. These findings underscore the importance of capturing and quantifying the impact of damaging genomic variants in the context of multiple, conditionally dependent variables, such as pre- and post-operative factors, and demography.


Single ventricle congenital heart disease is a birth defect. In these children, the heart has only one effective blood-pumping chamber instead of two. Surgery can reroute the blood to use only one chamber, but multiple risk factors influence how well a child develops afterwards. Studying these risk factors can be challenging because they are interconnected, i.e. children with a genetic birth defect may be more likely to have a lower birthweight, and hence more likely to spend longer in hospital after surgery. Here, we used a statistical approach not commonly applied to study congenital heart disease and describe that whether a genetic variant (a small difference in a child's DNA) is important for how a child with single ventricle heart disease develops and grows after surgery depends on the presence of other risk factors.

11.
bioRxiv ; 2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37333118

RESUMO

Rationale: Over 200 mutations in the sarcomeric protein ß-myosin heavy chain (MYH7) have been linked to hypertrophic cardiomyopathy (HCM). However, different mutations in MYH7 lead to variable penetrance and clinical severity, and alter myosin function to varying degrees, making it difficult to determine genotype-phenotype relationships, especially when caused by rare gene variants such as the G256E mutation. Objective: This study aims to determine the effects of low penetrant MYH7 G256E mutation on myosin function. We hypothesize that the G256E mutation would alter myosin function, precipitating compensatory responses in cellular functions. Methods: We developed a collaborative pipeline to characterize myosin function at multiple scales (protein to myofibril to cell to tissue). We also used our previously published data on other mutations to compare the degree to which myosin function was altered. Results: At the protein level, the G256E mutation disrupts the transducer region of the S1 head and reduces the fraction of myosin in the folded-back state by 50.9%, suggesting more myosins available for contraction. Myofibrils isolated from hiPSC-CMs CRISPR-edited with G256E (MYH7 WT/G256E ) generated greater tension, had faster tension development and slower early phase relaxation, suggesting altered myosin-actin crossbridge cycling kinetics. This hypercontractile phenotype persisted in single-cell hiPSC-CMs and engineered heart tissues. Single-cell transcriptomic and metabolic profiling demonstrated upregulation of mitochondrial genes and increased mitochondrial respiration, suggesting altered bioenergetics as an early feature of HCM. Conclusions: MYH7 G256E mutation causes structural instability in the transducer region, leading to hypercontractility across scales, perhaps from increased myosin recruitment and altered crossbridge cycling. Hypercontractile function of the mutant myosin was accompanied by increased mitochondrial respiration, while cellular hypertrophy was modest in the physiological stiffness environment. We believe that this multi-scale platform will be useful to elucidate genotype-phenotype relationships underlying other genetic cardiovascular diseases.

12.
Circ Genom Precis Med ; 16(3): 224-231, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37165897

RESUMO

BACKGROUND: Known genetic causes of congenital heart disease (CHD) explain <40% of CHD cases, and interpreting the clinical significance of variants with uncertain functional impact remains challenging. We aim to improve diagnostic classification of variants in patients with CHD by assessing the impact of noncanonical splice region variants on RNA splicing. METHODS: We tested de novo variants from trio studies of 2649 CHD probands and their parents, as well as rare (allele frequency, <2×10-6) variants from 4472 CHD probands in the Pediatric Cardiac Genetics Consortium through a combined computational and in vitro approach. RESULTS: We identified 53 de novo and 74 rare variants in CHD cases that alter splicing and thus are loss of function. Of these, 77 variants are in known dominant, recessive, and candidate CHD genes, including KMT2D and RBFOX2. In 1 case, we confirmed the variant's predicted impact on RNA splicing in RNA transcripts from the proband's cardiac tissue. Two probands were found to have 2 loss-of-function variants for recessive CHD genes HECTD1 and DYNC2H1. In addition, SpliceAI-a predictive algorithm for altered RNA splicing-has a positive predictive value of ≈93% in our cohort. CONCLUSIONS: Through assessment of RNA splicing, we identified a new loss-of-function variant within a CHD gene in 78 probands, of whom 69 (1.5%; n=4472) did not have a previously established genetic explanation for CHD. Identification of splice-altering variants improves diagnostic classification and genetic diagnoses for CHD. REGISTRATION: URL: https://clinicaltrials.gov; Unique identifier: NCT01196182.


Assuntos
Cardiopatias Congênitas , RNA , Criança , Humanos , Cardiopatias Congênitas/diagnóstico , Cardiopatias Congênitas/genética , Mutação , Splicing de RNA , Frequência do Gene , Fatores de Processamento de RNA/genética , Proteínas Repressoras/genética
13.
Nature ; 615(7951): 292-299, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36859543

RESUMO

Emotional states influence bodily physiology, as exemplified in the top-down process by which anxiety causes faster beating of the heart1-3. However, whether an increased heart rate might itself induce anxiety or fear responses is unclear3-8. Physiological theories of emotion, proposed over a century ago, have considered that in general, there could be an important and even dominant flow of information from the body to the brain9. Here, to formally test this idea, we developed a noninvasive optogenetic pacemaker for precise, cell-type-specific control of cardiac rhythms of up to 900 beats per minute in freely moving mice, enabled by a wearable micro-LED harness and the systemic viral delivery of a potent pump-like channelrhodopsin. We found that optically evoked tachycardia potently enhanced anxiety-like behaviour, but crucially only in risky contexts, indicating that both central (brain) and peripheral (body) processes may be involved in the development of emotional states. To identify potential mechanisms, we used whole-brain activity screening and electrophysiology to find brain regions that were activated by imposed cardiac rhythms. We identified the posterior insular cortex as a potential mediator of bottom-up cardiac interoceptive processing, and found that optogenetic inhibition of this brain region attenuated the anxiety-like behaviour that was induced by optical cardiac pacing. Together, these findings reveal that cells of both the body and the brain must be considered together to understand the origins of emotional or affective states. More broadly, our results define a generalizable approach for noninvasive, temporally precise functional investigations of joint organism-wide interactions among targeted cells during behaviour.


Assuntos
Comportamento Animal , Encéfalo , Emoções , Coração , Animais , Camundongos , Ansiedade/fisiopatologia , Encéfalo/fisiologia , Mapeamento Encefálico , Emoções/fisiologia , Coração/fisiologia , Comportamento Animal/fisiologia , Eletrofisiologia , Optogenética , Córtex Insular/fisiologia , Frequência Cardíaca , Channelrhodopsins , Taquicardia/fisiopatologia , Marca-Passo Artificial
14.
Am Heart J ; 259: 68-78, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36796574

RESUMO

In this manuscript, we describe the design and rationale of a randomized controlled trial in pediatric Fontan patients to test the hypothesis that a live-video-supervised exercise (aerobic+resistance) intervention will improve cardiac and physical capacity; muscle mass, strength, and function; and endothelial function. Survival of children with single ventricles beyond the neonatal period has increased dramatically with the staged Fontan palliation. Yet, long-term morbidity remains high. By age 40, 50% of Fontan patients will have died or undergone heart transplantation. Factors that contribute to onset and progression of heart failure in Fontan patients remain incompletely understood. However, it is established that Fontan patients have poor exercise capacity which is associated with a greater risk of morbidity and mortality. Furthermore, decreased muscle mass, abnormal muscle function, and endothelial dysfunction in this patient population is known to contribute to disease progression. In adult patients with 2 ventricles and heart failure, reduced exercise capacity, muscle mass, and muscle strength are powerful predictors of poor outcomes, and exercise interventions can not only improve exercise capacity and muscle mass, but also reverse endothelial dysfunction. Despite these known benefits of exercise, pediatric Fontan patients do not exercise routinely due to their chronic condition, perceived restrictions to exercise, and parental overprotection. Limited exercise interventions in children with congenital heart disease have demonstrated that exercise is safe and effective; however, these studies have been conducted in small, heterogeneous groups, and most had few Fontan patients. Critically, adherence is a major limitation in pediatric exercise interventions delivered on-site, with adherence rates as low as 10%, due to distance from site, transportation difficulties, and missed school or workdays. To overcome these challenges, we utilize live-video conferencing to deliver the supervised exercise sessions. Our multidisciplinary team of experts will assess the effectiveness of a live-video-supervised exercise intervention, rigorously designed to maximize adherence, and improve key and novel measures of health in pediatric Fontan patients associated with poor long-term outcomes. Our ultimate goal is the translation of this model to clinical application as an "exercise prescription" to intervene early in pediatric Fontan patients and decrease long-term morbidity and mortality.


Assuntos
Técnica de Fontan , Cardiopatias Congênitas , Insuficiência Cardíaca , Transplante de Coração , Adulto , Recém-Nascido , Humanos , Criança , Exercício Físico/fisiologia , Terapia por Exercício , Força Muscular , Teste de Esforço
15.
Am J Transplant ; 23(5): 611-618, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36796762

RESUMO

Epstein-Barr virus (EBV)-positive posttransplant lymphoproliferative disorder (PTLD) results in significant morbidity and mortality in pediatric transplant recipients. Identifying individuals at an increased risk of EBV-positive PTLD could influence clinical management of immunosuppression and other therapies, improving posttransplant outcomes. A 7-center prospective, observational clinical trial of 872 pediatric transplant recipients evaluated the presence of mutations at positions 212 and 366 of EBV latent membrane protein 1 (LMP1) as an indicator of risk of EBV-positive PTLD (clinical trials: NCT02182986). DNA was isolated from peripheral blood of EBV-positive PTLD case patients and matched controls (1:2 nested case:control), and the cytoplasmic tail of LMP1 was sequenced. Thirty-four participants reached the primary endpoint of biopsy-proven EBV-positive PTLD. DNA was sequenced from 32 PTLD case patients and 62 matched controls. Both LMP1 mutations were present in 31 of 32 PTLD cases (96.9%) and in 45 of 62 matched controls (72.6%) (P = .005; OR = 11.7; 95% confidence interval, 1.5, 92.6). The presence of both G212S and S366T carries a nearly 12-fold increased risk of development of EBV-positive PTLD. Conversely, transplant recipients without both LMP1 mutations carry a very low risk of PTLD. Analysis of mutations at positions 212 and 366 of LMP1 can be informative in stratifying patients for risk of EBV-positive PTLD.


Assuntos
Infecções por Vírus Epstein-Barr , Transtornos Linfoproliferativos , Humanos , Criança , Herpesvirus Humano 4/genética , Infecções por Vírus Epstein-Barr/complicações , Estudos Prospectivos , Transtornos Linfoproliferativos/etiologia , Mutação , Proteínas de Membrana
16.
J Mol Cell Cardiol ; 177: 28-37, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36841153

RESUMO

BACKGROUND: Previous studies have implicated p53-dependent mitochondrial dysfunction in sepsis induced end organ injury, including sepsis-induced myocardial dysfunction (SIMD). However, the mechanisms behind p53 localization to the mitochondria have not been well established. Dynamin-related protein 1 (Drp1), a mediator of mitochondrial fission, may play a role in p53 mitochondrial localization. Here we examined the role of Drp1/p53 interaction in SIMD using in vitro and murine models of sepsis. METHODS: H9c2 cardiomyoblasts and BALB/c mice were exposed to lipopolysaccharide (LPS) to model sepsis phenotype. Pharmacologic inhibitors of Drp1 activation (ψDrp1) and of p53 mitochondrial binding (pifithrin µ, PFTµ) were utilized to assess interaction between Drp1 and p53, and the subsequent downstream impact on mitochondrial morphology and function, cardiomyocyte function, and sepsis phenotype. RESULTS: Both in vitro and murine models demonstrated an increase in physical Drp1/p53 interaction following LPS treatment, which was associated with increased p53 mitochondrial localization, and mitochondrial dysfunction. This Drp1/p53 interaction was inhibited by ΨDrp1, suggesting that this interaction is dependent on Drp1 activation. Treatment of H9c2 cells with either ΨDrp1 or PFTµ inhibited the LPS mediated localization of Drp1/p53 to the mitochondria, decreased oxidative stress, improved cellular respiration and ATP production. Similarly, treatment of BALB/c mice with either ΨDrp1 or PFTµ decreased LPS-mediated mitochondrial localization of p53, mitochondrial ROS in cardiac tissue, and subsequently improved cardiomyocyte contractile function and survival. CONCLUSION: Drp1/p53 interaction and mitochondrial localization is a key prodrome to mitochondrial damage in SIMD and inhibiting this interaction may serve as a therapeutic target.


Assuntos
Cardiomiopatias , Sepse , Camundongos , Animais , Proteína Supressora de Tumor p53 , Lipopolissacarídeos/efeitos adversos , Cardiomiopatias/metabolismo , Dinaminas/metabolismo , Sepse/complicações , Sepse/induzido quimicamente , Dinâmica Mitocondrial/genética
17.
Dermatol Surg ; 49(4): 338-342, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36763896

RESUMO

BACKGROUND: Fractional ablative laser resurfacing has been shown to improve the final cosmetic appearance of surgical scars, but optimal timing is unknown. OBJECTIVE: To compare surgical scars treated with fractional carbon dioxide (CO 2 ) laser performed on Day 0 and Day 14. METHODS: Prospective, randomized, split-scar, physician-blinded study of 30 surgical scars on the limbs. Scars halves received fractional CO 2 laser on either Day 0 or Day 14. Scar assessment at 6 months evaluated patient preference, physician modified Manchester Scar Scale (MMSS) score, and quantitative scar analysis on histology (fractal dimension [F D ] and lacunarity [L] analysis). RESULTS: There was no significant difference in patient assessment (54% preferred Day 0 side, 46% preferred Day 14 side, p = .58) or physician assessment (mean MMSS 8.4 for Day 0 vs 8.7 for Day 14, p = .28). Fractal dimensions were similar for both interventions (mean 1.778 for Day 0 vs 1.781 for Day 14, p = .80). Lacunarity was similar for both interventions (mean 0.368 for Day 0 vs 0.345 for Day 14, p = .44). LIMITATIONS: Single-center study with wounds limited to limbs of skin Phototype I-II subjects; 4 of whom were lost to follow-up. CONCLUSION: Intraoperative CO 2 laser is noninferior to Day 14 laser resurfacing for surgical scar treatment.


Assuntos
Terapia a Laser , Lasers de Gás , Neoplasias Cutâneas , Humanos , Cicatriz/etiologia , Cicatriz/cirurgia , Cicatriz/patologia , Terapia a Laser/efeitos adversos , Terapia a Laser/métodos , Lasers de Gás/uso terapêutico , Estudos Prospectivos , Neoplasias Cutâneas/cirurgia , Resultado do Tratamento
18.
Memory ; 31(3): 328-345, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36656687

RESUMO

The Transfer-appropriate Processing (TAP) framework has demonstrated enhanced recognition memory when processing operations engaged at encoding and at test match. Our research applied TAP to study the illusory truth effect (ITE). We investigated whether the match/mismatch of evaluative goals at encoding and at test affects the ITE. At encoding, participants saw target words (Experiments 1-3; or full trivia claims Experiments 4-5) and completed an evaluative goal: imagery task or vowel-counting. At test, participants saw target words embedded in trivia claims that were old or new and completed the same (matching) or different (mismatching) evaluative goal that they completed at encoding, before making truth or memory ratings. We found a typical TAP effect for memory judgements when people saw words at encoding, but no TAP effect when people saw claims at encoding. We also found an ITE when people saw claims at encoding, but no ITE when people saw words at encoding (no evidence of TAP moderating truth judgments). Together these results extend both the TAP and ITE literatures, suggesting boundary conditions for TAP and the conditions under which the ITE emerges.


Assuntos
Ilusões , Reconhecimento Psicológico , Humanos , Julgamento , Motivação
19.
Emotion ; 23(1): 261-277, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35191719

RESUMO

People who learn the outcome to a situation or problem tend to overestimate what was known in the past-this is hindsight bias. Whereas previous research has revealed robust hindsight bias in the visual domain, little is known about how outcome information affects our memory of others' emotional expressions. The goal of the current work was to test whether participants exhibited hindsight bias for emotional faces and whether this varied as a function of emotion. Across five experiments, participants saw images of faces displaying different emotions. In the foresight phase, participants watched several emotional faces gradually clarify from blurry to clear. Once participants believed they knew what emotion the face was exhibiting, they identified the emotion from several options (e.g., angry, disgusted, happy, scared, surprised). In the hindsight phase, participants saw clear versions of each face before stopping the clarification at the point at which they previously identified the emotional expression. On average, participants exhibited hindsight bias for all emotions except happy faces (i.e., they indicated that they identified the emotional expressions at a blurrier point in hindsight than they had in foresight). A multinomial processing tree model of our data revealed that this was not due to participants' better recollection of foresight judgments for happy faces compared to the other emotions. Additionally, participants showed a smaller reconstruction bias for happy faces than the other emotions. We discuss the social implications of these findings as well as the potential for this paradigm to be used across cultures and ages. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Assuntos
Emoções , Medo , Humanos , Ira , Julgamento , Felicidade , Expressão Facial
20.
Pediatr Transplant ; 27(1): e14421, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36303275

RESUMO

BACKGROUND: Infectious complications are a major cause of morbidity and mortality after HT. Fontan patients may be more susceptible to post-HT infections. METHODS: This was a single-center, retrospective cohort analysis of pediatric patients undergoing HT for FF physiology or DCM, who underwent induction with ATG. The primary endpoint was an infection in the first 180 days post-HT, defined as positive (1) blood/urine/respiratory culture; (2) viral PCR; (3) skin or wound infection; and/or (4) culture-negative infection if ≥5 days of antibiotics were completed. Secondary endpoints included (1) cell counts after ATG; (2) PTLD; and (3) rejection (≥Grade 2R ACR or pAMR2) in the first 180 days post-HT. RESULTS: A total of 59 patients (26 FF, 33 DCM) underwent HT at 14.7 (IQR 10.6, 19.5) and 11.7 (IQR 1.4, 13.6) years of age, respectively. The median total ATG received was 7.4 (IQR 4.9, 7.7) vs 7.5 (IQR 7.3, 7.6) mg/kg (p = NS) for FF and DCM patients, respectively. Twenty-three patients (39%) developed an infection 180 days post-HT, with a higher rate of infection in FF patients (54% vs 27%, p = .03). Adjusted for pre-transplant absolute lymphocyte count, FF patients had a higher risk of infection at 30 days post-HT (OR 7.62, 95% CI 1.13-51.48, p = .04). There was no difference in the incidence of PTLD (12% vs 0%; p = .08) or rejection (12% vs 21%; p = .49). CONCLUSION: Compared to DCM patients, FF patients have a higher risk of infection. Modifications to induction therapy for FF patients should be considered.


Assuntos
Transplante de Coração , Humanos , Criança , Estudos Retrospectivos , Transplante de Coração/efeitos adversos , Estudos de Coortes , Incidência
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