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BACKGROUND: The failing heart is traditionally described as metabolically inflexible and oxygen starved, causing energetic deficit and contractile dysfunction. Current metabolic modulator therapies aim to increase glucose oxidation to increase oxygen efficiency of adenosine triphosphate production, with mixed results. METHODS: To investigate metabolic flexibility and oxygen delivery in the failing heart, 20 patients with nonischemic heart failure with reduced ejection fraction (left ventricular ejection fraction 34.9±9.1) underwent separate infusions of insulin+glucose infusion (I+G) or Intralipid infusion. We used cardiovascular magnetic resonance to assess cardiac function and measured energetics using phosphorus-31 magnetic resonance spectroscopy. To investigate the effects of these infusions on cardiac substrate use, function, and myocardial oxygen uptake (MVo2), invasive arteriovenous sampling and pressure-volume loops were performed (n=9). RESULTS: At rest, we found that the heart had considerable metabolic flexibility. During I+G, cardiac glucose uptake and oxidation were predominant (70±14% total energy substrate for adenosine triphosphate production versus 17±16% for Intralipid; P=0.002); however, no change in cardiac function was seen relative to basal conditions. In contrast, during Intralipid infusion, cardiac long-chain fatty acid (LCFA) delivery, uptake, LCFA acylcarnitine production, and fatty acid oxidation were all increased (LCFA 73±17% of total substrate versus 19±26% total during I+G; P=0.009). Myocardial energetics were better with Intralipid compared with I+G (phosphocreatine/adenosine triphosphate 1.86±0.25 versus 2.01±0.33; P=0.02), and systolic and diastolic function were improved (LVEF 34.9±9.1 baseline, 33.7±8.2 I+G, 39.9±9.3 Intralipid; P<0.001). During increased cardiac workload, LCFA uptake and oxidation were again increased during both infusions. There was no evidence of systolic dysfunction or lactate efflux at 65% maximal heart rate, suggesting that a metabolic switch to fat did not cause clinically meaningful ischemic metabolism. CONCLUSIONS: Our findings show that even in nonischemic heart failure with reduced ejection fraction with severely impaired systolic function, significant cardiac metabolic flexibility is retained, including the ability to alter substrate use to match both arterial supply and changes in workload. Increasing LCFA uptake and oxidation is associated with improved myocardial energetics and contractility. Together, these findings challenge aspects of the rationale underlying existing metabolic therapies for heart failure and suggest that strategies promoting fatty acid oxidation may form the basis for future therapies.
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Insuficiência Cardíaca , Disfunção Ventricular Esquerda , Humanos , Volume Sistólico , Metabolismo Energético , Função Ventricular Esquerda , Miocárdio/metabolismo , Insuficiência Cardíaca/patologia , Trifosfato de Adenosina/metabolismo , Disfunção Ventricular Esquerda/patologia , Ácidos Graxos/metabolismo , Glucose/metabolismo , Oxigênio/metabolismoRESUMO
Obesity is associated with important changes in cardiac energetics and function, and an increased risk of adverse cardiovascular outcomes. Multi-nuclear MRS and MRI techniques have the potential to provide a comprehensive non-invasive assessment of cardiac metabolic perturbation in obesity. A rat model of obesity was created by high-fat diet feeding. This model was characterized using in vivo hyperpolarized [1-13C]pyruvate and [2-13C]pyruvate MRS, echocardiography and perfused heart 31P MRS. Two groups of obese rats were subsequently treated with either caloric restriction or the glucagon-like peptide-1 analogue/agonist liraglutide, prior to reassessment. The model recapitulated cardiovascular consequences of human obesity, including mild left ventricular hypertrophy, and diastolic, but not systolic, dysfunction. Hyperpolarized 13C and 31P MRS demonstrated that obesity was associated with reduced myocardial pyruvate dehydrogenase flux, altered cardiac tricarboxylic acid (TCA) cycle metabolism, and impaired myocardial energetic status (lower phosphocreatine to adenosine triphosphate ratio and impaired cardiac ΔG~ATP). Both caloric restriction and liraglutide treatment were associated with normalization of metabolic changes, alongside improvement in cardiac diastolic function. In this model of obesity, hyperpolarized 13C and 31P MRS demonstrated abnormalities in cardiac metabolism at multiple levels, including myocardial substrate selection, TCA cycle, and high-energy phosphorus metabolism. Metabolic changes were linked with impairment of diastolic function and were reversed in concert following either caloric restriction or liraglutide treatment. With hyperpolarized 13C and 31P techniques now available for human use, the findings support a role for multi-nuclear MRS in the development of new therapies for obesity.
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In health, the human heart is able to match ATP supply and demand perfectly. It requires 6 kg of ATP per day to satisfy demands of external work (mechanical force generation) and internal work (ion movements and basal metabolism). The heart is able to link supply with demand via direct responses to ADP and AMP concentrations but calcium concentrations within myocytes play a key role, signalling both inotropy, chronotropy and matched increases in ATP production. Calcium/calmodulin-dependent protein kinase (CaMKII) is a key adapter to increased workload, facilitating a greater and more rapid calcium concentration change. In the failing heart, this is dysfunctional and ATP supply is impaired. This review aims to examine the mechanisms and pathologies that link increased energy demand to this disrupted situation. We examine the roles of calcium loading, oxidative stress, mitochondrial structural abnormalities and damage-associated molecular patterns.
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This study examines whether gestational age, birth weight, and early term birth is associated with childhood mental disorders in 342 pregnant women recruited at less than 20 weeks gestation and were then followed up until 4 years postpartum, including 93 children born at early term. Women were assessed at recruitment using the Structured Clinical Interview for DSM. At 4 years of age their children were assessed using the Preschool Age Psychiatric Assessment (PAPA) and the Child Behavior Checklist (CBCL). This study found earlier birth predicted an increased risk for anxiety disorders and demonstrated a significant interaction between gestational age and lower birthweight. The risk for ADHD increased with lower gestational age independent of birthweight. In contrast, gestational age was not associated with Oppositional Defiant Disorder, Conduct Disorder, internalizing or externalizing symptoms. These findings highlight the important differences in the association of early term birth and vulnerability for specific mental disorders.
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Heart failure with preserved ejection fraction (HFpEF) is recognised as an increasingly prevalent, morbid and burdensome condition with a poor outlook. Recent advances in both the understanding of HFpEF and the technological ability to image cardiac function and metabolism in humans have simultaneously shone a light on the molecular basis of this complex condition of diastolic dysfunction, and the inflammatory and metabolic changes that are associated with it, typically in the context of a complex patient. This review both makes the case for an integrated assessment of the condition, and highlights that metabolic alteration may be a measurable outcome for novel targeted forms of medical therapy. It furthermore highlights how recent technological advancements and advanced medical imaging techniques have enabled the characterisation of the metabolism and function of HFpEF within patients, at rest and during exercise.
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Insuficiência Cardíaca , Humanos , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/tratamento farmacológico , Volume Sistólico , Diagnóstico por Imagem , Exercício Físico , Função Ventricular EsquerdaRESUMO
Childhood anxiety disorders (CAD) are a common childhood mental disorder and understanding early developmental pathways is key to prevention and early intervention. What is not understood is whether early life stress predictors of CAD might be both mediated by infant cortisol reactivity and moderated by infant attachment status. To address this question, this exploratory study draws on 190 women recruited in early pregnancy and followed together with their children until 4 years of age. Early life stress is operationalized as maternal depression measured using the Structured Clinical Interview for the DSM, Childhood Trauma Questionnaire, Parenting Stress Index, and antenatal maternal hair cortisol concentrations. Infant cortisol reactivity was measured at 12 months together with the Strange Situation Procedure and CAD assessed at 4 years of age using the Preschool Age Psychiatric Assessment. There was no direct association between attachment classification and CAD. Furthermore, infant cortisol reactivity neither mediated nor attachment moderated the association of early life stress predictors and CAD. However, only for infants with organized attachment classifications, higher maternal antenatal depression, and hair cortisol were associated with a higher risk of CAD.
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Depressão , Hidrocortisona , Lactente , Criança , Feminino , Humanos , Gravidez , Pré-Escolar , Depressão/metabolismo , Hidrocortisona/metabolismo , Estresse Psicológico/complicações , Transtornos de Ansiedade , Poder FamiliarRESUMO
OBJECTIVE: Perinatal emotional well-being is more than the presence or absence of depressive and anxiety disorders; it encompasses a wide range of factors that contribute to emotional well-being. This study compares perinatal well-being between women living in metropolitan and rural regions. DESIGN: Prospective, longitudinal cohort. PARTICIPANTS/SETTING: Eight hundred and six women from Victoria and Western Australia recruited before 20 weeks of pregnancy and followed up to 12 months postpartum. MAIN OUTCOME MEASURES: Rurality was assessed using the Modified Monash Model (MM Model) with 578 in metropolitan cities MM1, 185 in regional and large rural towns MM2-MM3 and 43 in rural to remote MM4-MM7. The Structured Clinical Interview for DSM-IV (SCID-IV) was administered at recruitment to assess depression, and symptoms of depression and anxiety were measured using the Edinburgh Post-natal Depression Scale and the State and Trait Anxiety Scale, respectively. Other measures included stressful events, diet, exercise, partner support, parenting and sleep. RESULTS: The prevalence of depressive disorders did not differ across rurality. There was also no difference in breastfeeding cessation, exercise, sleep or partner support. Women living in rural communities and who also had depression reported significantly higher parenting stress than metropolitan women and lower access to parenting activities. CONCLUSIONS: Our study suggests while many of the challenges of the perinatal period were shared between women in all areas, there were important differences in parenting stress and access to activities. Furthermore, these findings suggest that guidelines and interventions designed for perinatal mental health should consider rurality.
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Saúde Mental , População Rural , Gravidez , Feminino , Humanos , Estudos Prospectivos , Vitória/epidemiologia , Depressão/epidemiologia , Depressão/psicologiaRESUMO
BACKGROUND: Transient pulmonary congestion during exercise is emerging as an important determinant of reduced exercise capacity in heart failure with preserved ejection fraction (HFpEF). We sought to determine whether an abnormal cardiac energetic state underpins this process. METHODS: We recruited patients across the spectrum of diastolic dysfunction and HFpEF (controls, n=11; type 2 diabetes, n=9; HFpEF, n=14; and severe diastolic dysfunction attributable to cardiac amyloidosis, n=9). Cardiac energetics were measured using phosphorus spectroscopy to define the myocardial phosphocreatine to ATP ratio. Cardiac function was assessed by cardiovascular magnetic resonance cine imaging and echocardiography and lung water using magnetic resonance proton density mapping. Studies were performed at rest and during submaximal exercise using a magnetic resonance imaging ergometer. RESULTS: Paralleling the stepwise decline in diastolic function across the groups (E/e' ratio; P<0.001) was an increase in NT-proBNP (N-terminal pro-brain natriuretic peptide; P<0.001) and a reduction in phosphocreatine/ATP ratio (control, 2.15 [2.09, 2.29]; type 2 diabetes, 1.71 [1.61, 1.91]; HFpEF, 1.66 [1.44, 1.89]; cardiac amyloidosis, 1.30 [1.16, 1.53]; P<0.001). During 20-W exercise, lower left ventricular diastolic filling rates (r=0.58; P<0.001), lower left ventricular diastolic reserve (r=0.55; P<0.001), left atrial dilatation (r=-0.52; P<0.001), lower right ventricular contractile reserve (right ventricular ejection fraction change, r=0.57; P<0.001), and right atrial dilation (r=-0.71; P<0.001) were all linked to lower phosphocreatine/ATP ratio. Along with these changes, pulmonary proton density mapping revealed transient pulmonary congestion in patients with HFpEF (+4.4% [0.5, 6.4]; P=0.002) and cardiac amyloidosis (+6.4% [3.3, 10.0]; P=0.004), which was not seen in healthy controls (-0.1% [-1.9, 2.1]; P=0.89) or type 2 diabetes without HFpEF (+0.8% [-1.7, 1.9]; P=0.82). The development of exercise-induced pulmonary congestion was associated with lower phosphocreatine/ATP ratio (r=-0.43; P=0.004). CONCLUSIONS: A gradient of myocardial energetic deficit exists across the spectrum of HFpEF. Even at low workload, this energetic deficit is related to markedly abnormal exercise responses in all 4 cardiac chambers, which is associated with detectable pulmonary congestion. The findings support an energetic basis for transient pulmonary congestion in HFpEF.
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Exercício Físico/efeitos adversos , Insuficiência Cardíaca Diastólica/diagnóstico , Insuficiência Cardíaca Diastólica/etiologia , Hiperemia/complicações , Hiperemia/fisiopatologia , Circulação Pulmonar , Idoso , Biomarcadores , Suscetibilidade a Doenças , Ecocardiografia , Teste de Esforço , Feminino , Testes de Função Cardíaca , Humanos , Hiperemia/diagnóstico , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Edema Pulmonar/diagnóstico , Índice de Gravidade de Doença , Volume Sistólico , Função Ventricular EsquerdaRESUMO
BACKGROUND: The development of childhood anxiety disorders (CADs) is likely to depend on pathways that can be programmed by early-life risk factors. We test the hypothesis that early-life maternal factors can predict this programming effect on CAD. METHODS: Data were obtained from 198 women and children from the Mercy Pregnancy and Emotional Wellbeing Study (MPEWS), a cohort study with data collected across pregnancy, postpartum and until 4 years of age. Maternal antenatal depression was measured using the Structured Clinical Interview for DSM-IV (SCID-IV), together with antenatal hair cortisol concentrations, maternal childhood trauma and parenting stress at 6 months postpartum. CAD was assessed with the Preschool Age Psychiatric Assessment and the Child Behaviour Checklist. RESULTS: Antenatal depression, a history of maternal childhood trauma and lower gestational age at birth were each associated with anxiety disorders at 4 years of age in their children. A multivariate binary logistic model with these early predictors explained approximately 9% of variance in CAD outcome at 4 years of age; however, only maternal trauma and gestational age were significant predictors in the model. The effect of early parenting stress on CAD was found to vary by the concentration of maternal antenatal hair cortisol, whereby postpartum parenting stress was associated with CAD only when there were higher maternal antenatal cortisol levels. CONCLUSIONS: This study suggests the importance of maternal factors pre-conception, pregnancy and in the postnatal period, which predict CADs and this is consistent with a developmental programming hypothesis for CAD.
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Depressão Pós-Parto , Transtorno Depressivo , Complicações na Gravidez , Ansiedade , Transtornos de Ansiedade/epidemiologia , Transtornos de Ansiedade/psicologia , Criança , Pré-Escolar , Estudos de Coortes , Depressão/psicologia , Transtorno Depressivo/psicologia , Feminino , Humanos , Recém-Nascido , Mães/psicologia , Poder Familiar/psicologia , Gravidez , Complicações na Gravidez/epidemiologia , Complicações na Gravidez/psicologiaRESUMO
RATIONALE: The recent development of hyperpolarized 13C magnetic resonance spectroscopy has made it possible to measure cellular metabolism in vivo, in real time. OBJECTIVE: By comparing participants with and without type 2 diabetes mellitus (T2DM), we report the first case-control study to use this technique to record changes in cardiac metabolism in the healthy and diseased human heart. METHODS AND RESULTS: Thirteen people with T2DM (glycated hemoglobin, 6.9±1.0%) and 12 age-matched healthy controls underwent assessment of cardiac systolic and diastolic function, myocardial energetics (31P-magnetic resonance spectroscopy), and lipid content (1H-magnetic resonance spectroscopy) in the fasted state. In a subset (5 T2DM, 5 control), hyperpolarized [1-13C]pyruvate magnetic resonance spectra were also acquired and in 5 of these participants (3 T2DM, 2 controls), this was successfully repeated 45 minutes after a 75 g oral glucose challenge. Downstream metabolism of [1-13C]pyruvate via PDH (pyruvate dehydrogenase, [13C]bicarbonate), lactate dehydrogenase ([1-13C]lactate), and alanine transaminase ([1-13C]alanine) was assessed. Metabolic flux through cardiac PDH was significantly reduced in the people with T2DM (Fasted: 0.0084±0.0067 [Control] versus 0.0016±0.0014 [T2DM], Fed: 0.0184±0.0109 versus 0.0053±0.0041; P=0.013). In addition, a significant increase in metabolic flux through PDH was observed after the oral glucose challenge (P<0.001). As is characteristic of diabetes mellitus, impaired myocardial energetics, myocardial lipid content, and diastolic function were also demonstrated in the wider study cohort. CONCLUSIONS: This work represents the first demonstration of the ability of hyperpolarized 13C magnetic resonance spectroscopy to noninvasively assess physiological and pathological changes in cardiac metabolism in the human heart. In doing so, we highlight the potential of the technique to detect and quantify metabolic alterations in the setting of cardiovascular disease.
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Diabetes Mellitus Tipo 2/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Miocárdio/metabolismo , Idoso , Idoso de 80 Anos ou mais , Alanina Transaminase/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Jejum/metabolismo , Feminino , Glucose/metabolismo , Humanos , L-Lactato Desidrogenase/metabolismo , Masculino , Pessoa de Meia-Idade , Complexo Piruvato Desidrogenase/metabolismo , Ácido Pirúvico/metabolismoRESUMO
Understanding if maternal depression is a predictor of infant-parent attachment classification is important to furthering knowledge about the early pathways and predictors of socio-emotional development. Yet few studies that have utilised the Strange Situation Procedure, the gold standard for measurement of infant-parent attachment, have examined antenatal depression as a predictor of attachment, and none has also included a measure of maternal trauma. This study uses data on 224 women recruited in early pregnancy and followed up until 12 months postpartum. Maternal depression was measured in pregnancy using the Structured Clinical Interview for the DSM and repeat Edinburgh Postnatal Depression Scale as well as Stressful Life Events scale across pregnancy and postpartum including items on domestic violence. A past history of trauma was measured using the Childhood Trauma Questionnaire. Attachment was measured using the Strange Situation Procedure (SSP) at 12 months postpartum. We found that maternal depression was not associated with insecure or disorganized attachment. However, a maternal history of childhood trauma and current domestic violence both predicted insecure-avoidant attachment at 12 months, whereas increased number of stressful life events prior to conception and in pregnancy was associated with insecure-resistant attachment. Neither trauma, past or current, nor depression predicted disorganized attachment. In the first study to have included measures of antenatal depression, maternal childhood trauma, and current stressful events as predictors of infant attachment measured using the SSP, we found maternal experiences of past and current trauma but not depression were significant predictors of infant-parent attachment security.
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Depressão Pós-Parto , Transtorno Depressivo , Depressão/diagnóstico , Depressão/psicologia , Depressão Pós-Parto/diagnóstico , Depressão Pós-Parto/epidemiologia , Depressão Pós-Parto/psicologia , Feminino , Humanos , Lactente , Relações Mãe-Filho/psicologia , Mães/psicologia , Apego ao Objeto , Pais , GravidezRESUMO
OBJECTIVE: Understanding the relationship between attachment and mental health has an important role in informing management of perinatal mental disorders and for infant mental health. It has been suggested that experiences of attachment are transmitted from one generation to the next. Maternal sensitivity has been proposed as a mediator, although findings have not been as strong as hypothesised. A meta-analysis suggested that this intergenerational transmission of attachment may vary across populations with lower concordance between parent and infant attachment classifications in clinical compared to community samples. However, no previous study has examined major depression and adult attachment in pregnancy as predictors of infant-parent attachment classification at 12 months postpartum. METHODS: Data were obtained on 52 first-time mothers recruited in early pregnancy, which included 22 women who met diagnostic criteria for current major depression using the Structured Clinical Interview for the Diagnostic and Statistical Manual of Mental Disorders. The Adult Attachment Interview was also administered before 20 weeks of pregnancy. A history of early trauma was measured using the Childhood Trauma Questionnaire and maternal sensitivity was measured at 6 months postpartum using the observational measure of the Emotional Availability Scales. Infant-parent attachment was measured using the Strange Situation Procedure at 12 months. RESULTS: Overall, we found no significant association between the Adult Attachment Interview and the Strange Situation Procedure classifications. However, a combination of maternal non-autonomous attachment on the Adult Attachment Interview and major depression was a significant predictor of insecure attachment on the Strange Situation Procedure. We did not find that maternal sensitivity mediated parental and infant attachment security in this sample. CONCLUSION: While previous meta-analyses identified lower concordance in clinical samples, our findings suggest women with major depression and non-autonomous attachment have a greater concordance with insecure attachment on the Strange Situation Procedure. These findings can guide future research and suggest a focus on depression in pregnancy may be important for subsequent infant attachment.
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Depressão Pós-Parto , Transtorno Depressivo Maior , Adulto , Estudos de Coortes , Depressão , Depressão Pós-Parto/diagnóstico , Feminino , Humanos , Lactente , Relações Mãe-Filho/psicologia , Apego ao Objeto , GravidezRESUMO
AIM: This paper aims to examine the maternal and child mental health and parenting outcomes in the context of COVID-19 pandemic conditions using a sample from Melbourne, Australia - a city exposed to one of the longest lockdowns world-wide in response to the pandemic. METHODS: This study utilises observational data from a prospective, pregnancy cohort, Mercy Pregnancy Emotional Wellbeing Study and includes 468 women and their children followed up in Melbourne to 3-4 years postpartum pre-COVID pandemic and compared to those followed up during the COVID-19 pandemic. RESULTS: When compared to mothers followed up at 3-4 years postpartum pre-pandemic, those followed up during the COVID-19 pandemic showed higher depressive symptoms with a steep incline in their symptom trajectory (EMMdifference = 1.72, Bonferroni-corrected P < 0.01, d = 0.35) and had a three times higher risk of scoring 13 or above on the EPDS (aRR = 3.22, Bonferroni-corrected P < 0.01). Although this increase was not associated with the variation in the duration of exposure to pandemic conditions, the steep increase in depressive symptoms was more pronounced in those with pre-existing depressive disorders. There was no difference in parenting stress or adjusted childhood mental health symptoms or disorder. CONCLUSIONS: Our findings highlight the vulnerability of those with pre-existing clinical mental health disorders and the need for adequate clinical care for this vulnerable group. Equally, our study indicates the possibility that parenting and early childhood mental health outcomes, at least in the short term, may be resilient.
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COVID-19 , Poder Familiar , Gravidez , Criança , Feminino , Pré-Escolar , Humanos , Poder Familiar/psicologia , Pandemias , Saúde Mental , Depressão/epidemiologia , Depressão/diagnóstico , COVID-19/epidemiologia , Estudos Prospectivos , Controle de Doenças Transmissíveis , Mães/psicologiaRESUMO
Therapist factors are generally thought to be important predictors of the capacity to understand and respond to clinical material. The current study aims to identify which features of personality and clinical symptomatology predict a trainee therapist's rating of cognitive behavioural (CB) and psychodynamic interpersonal (PI) processes in video recordings of these therapies. Eighty psychology trainees completed the Minnesota Multiphasic Personality Inventory-2-Restructured Form (MMPI-2-RF) and watched two video recordings of therapy sessions showing prototypical examples of CB and PI psychotherapy, rating the processes they could identify using the Comparative Psychotherapy Process Scale (CPPS). Trainees accurately differentiated CB from PI process while viewing the CB session but rated the CB video higher in PI processes than the PI video itself. Bayesian regression models showed that the most consistent MMPI-2-RF scale that predicted variance in ratings was hypomanic activation (RC9) predicting higher ratings of all psychotherapy processes in both conditions, while clinical scale factors such as Aggressiveness-Revised (AGGR-r) and personality scale factors of Psychoticism-Revised (PSYC-r) and Negative Emotionality/Neuroticism-Revised (NEGE-r) showed some notable but less consistent predictions. The variances in psychotherapy process ratings accounted for by MMPI-2-RF scales ranged from 15% to 51%. The study suggests that some clinical symptoms and personality factors do influence the rating of psychotherapy processes by psychology trainees, but further studies would be required to substantiate such findings. These findings have relevance to therapist training and selection for clinical training and therapist mental health.
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MMPI , Transtornos da Personalidade , Humanos , Teorema de Bayes , Transtornos da Personalidade/terapia , Transtornos da Personalidade/diagnóstico , Personalidade , CogniçãoRESUMO
Nicotinic acid receptor agonists have previously been shown to cause acute reductions in cardiac contractility. We sought to uncover the changes in cardiac metabolism underlying these alterations in function. In nine humans, we recorded cardiac energetics and function before and after a single oral dose of nicotinic acid using cardiac MRI to demonstrate contractile function and Phosphorus-31 (31 P) magnetic resonance spectroscopy to demonstrate myocardial energetics. Nicotinic Acid 400 mg lowered ejection fraction by 4% (64 ± 8% to 60 ± 7%, P = .03), and was accompanied by a fall in phosphocreatine/ATP ratio by 0.4 (2.2 ± 0.4 to 1.8 ± 0.1, P = .04). In four groups of eight Wistar rats, we used pyruvate dehydrogenase (PDH) flux studies to demonstrate changes in carbohydrate metabolism induced by the nicotinic acid receptor agonist, Acipimox, using hyperpolarized Carbon-13 (13 C) magnetic resonance spectroscopy. In rats which had been starved overnight, Acipimox caused a fall in ejection fraction by 7.8% (67.5 ± 8.9 to 60 ± 3.1, P = .03) and a nearly threefold rise in flux through PDH (from 0.182 ± 0.114 to 0.486 ± 0.139, P = .002), though this rise did not match pyruvate dehydrogenase flux observed in rats fed carbohydrate rich chow (0.726 ± 0.201). In fed rats, Acipimox decreased pyruvate dehydrogenase flux (to 0.512 ± 0.13, P = .04). Concentration of plasma insulin fell by two-thirds in fed rats administered Acipimox (from 1695 ± 891 ng/L to 550 ± 222 ng/L, P = .005) in spite of glucose concentrations remaining the same. In conclusion, we demonstrate that nicotinic acid receptor agonists impair cardiac contractility associated with a decline in cardiac energetics and show that the mechanism is likely a combination of reduced fatty acid availability and a failure to upregulate carbohydrate metabolism, essentially starving the heart of fuel.
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Metabolismo Energético , Coração/efeitos dos fármacos , Hipolipemiantes/farmacologia , Contração Miocárdica , Niacina/análogos & derivados , Pirazinas/farmacologia , Receptores Acoplados a Proteínas G/agonistas , Trifosfato de Adenosina/sangue , Adulto , Animais , Metabolismo dos Carboidratos , Humanos , Hipolipemiantes/administração & dosagem , Insulina/sangue , Masculino , Fosfocreatina/sangue , Pirazinas/administração & dosagem , Complexo Piruvato Desidrogenase/metabolismo , Ratos , Ratos WistarRESUMO
OBJECTIVE: Poorer mother-infant interaction quality has been identified among women with major depression; however, there is a dearth of research examining the impact of bipolar disorder. This study sought to compare mother-infant emotional availability at 6 months postpartum among women with perinatal major depressive disorder, bipolar disorder and no disorder (control). METHODS: Data were obtained for 127 mother-infant dyads from an Australian pregnancy cohort. The Structured Clinical Interview for the DSM-5 was used to diagnose major depressive disorder (n = 60) and bipolar disorder (n = 12) in early pregnancy (less than 20 weeks) and review diagnosis at 6 months postpartum. Prenatal and postnatal depressive symptoms were measured using the Edinburgh Postnatal Depression Scale, along with self-report psychotropic medication use. Mother and infant's interaction quality was measured using the Emotional Availability Scales when infants reached 6 months of age. Multivariate analyses of covariance examining the effects of major depressive disorder and bipolar disorder on maternal emotional availability (sensitivity, structuring, non-intrusiveness, non-hostility) and child emotional availability (responsiveness, involvement) were conducted. RESULTS: After controlling for maternal age and postpartum depressive symptoms, perinatal disorder (major depressive disorder, bipolar disorder) accounted for 17% of the variance in maternal and child emotional availability combined. Compared to women with major depressive disorder and their infants, women with bipolar disorder and their infants displayed lower ratings across all maternal and child emotional availability qualities, with the greatest mean difference seen in non-intrusiveness scores. CONCLUSIONS: Findings suggest that perinatal bipolar disorder may be associated with additional risk, beyond major depressive disorder alone, to a mother and her offspring's emotional availability at 6 months postpartum, particularly in maternal intrusiveness.
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Transtorno Bipolar , Depressão Pós-Parto , Transtorno Depressivo Maior , Complicações na Gravidez , Austrália , Estudos de Coortes , Depressão , Feminino , Humanos , Lactente , GravidezRESUMO
Understanding how a mother's traumatic experiences influence her interactions with her infant may have importance for understanding infant development and mental health. Data for this study were drawn from an Australian pregnancy cohort, the Mercy Pregnancy and Emotional Wellbeing Study. Maternal trauma from Childhood, Childbirth Experiences, and Stressful Life Events were examined. At six-months postpartum, 211 predominantly first-time mothers (mean age 31.5 years), and their infants, were video-recorded interacting for 40 minutes. Interactions were assessed with the Emotional Availability (EA) Scales. Using structural equation modelling to test multiple mediation pathways, moderate-to-severe childhood trauma had only a direct effect on reducing maternal EA with the infant (ß=-.17, p=.031), as did current stressful life events (ß=-.19, p=.019), after controlling for maternal depression, age, and tertiary education. This highlights that proximate trauma specific to the perinatal period may not account for the effect of distal childhood trauma on maternal EA at six-months postpartum.
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Depressão Pós-Parto , Mães , Adulto , Austrália , Criança , Emoções , Feminino , Humanos , Lactente , Saúde Mental , Relações Mãe-Filho , Apego ao Objeto , GravidezRESUMO
RATIONALE: Current cardiovascular clinical imaging techniques offer only limited assessment of innate immune cell-driven inflammation, which is a potential therapeutic target in myocardial infarction (MI) and other diseases. Hyperpolarized magnetic resonance (MR) is an emerging imaging technology that generates contrast agents with 10- to 20 000-fold improvements in MR signal, enabling cardiac metabolite mapping. OBJECTIVE: To determine whether hyperpolarized MR using [1-13C]pyruvate can assess the local cardiac inflammatory response after MI. METHODS AND RESULTS: We performed hyperpolarized [1-13C]pyruvate MR studies in small and large animal models of MI and in macrophage-like cell lines and measured the resulting [1-13C]lactate signals. MI caused intense [1-13C]lactate signal in healing myocardial segments at both day 3 and 7 after rodent MI, which was normalized at both time points after monocyte/macrophage depletion. A near-identical [1-13C]lactate signature was also seen at day 7 after experimental MI in pigs. Hyperpolarized [1-13C]pyruvate MR spectroscopy in macrophage-like cell suspensions demonstrated that macrophage activation and polarization with lipopolysaccharide almost doubled hyperpolarized lactate label flux rates in vitro; blockade of glycolysis with 2-deoxyglucose in activated cells normalized lactate label flux rates and markedly inhibited the production of key proinflammatory cytokines. Systemic administration of 2-deoxyglucose after rodent MI normalized the hyperpolarized [1-13C]lactate signal in healing myocardial segments at day 3 and also caused dose-dependent improvement in IL (interleukin)-1ß expression in infarct tissue without impairing the production of key reparative cytokines. Cine MRI demonstrated improvements in systolic function in 2-DG (2-deoxyglucose)-treated rats at 3 months. CONCLUSIONS: Hyperpolarized MR using [1-13C]pyruvate provides a novel method for the assessment of innate immune cell-driven inflammation in the heart after MI, with broad potential applicability across other cardiovascular disease states and suitability for early clinical translation.
Assuntos
Espectroscopia de Ressonância Magnética Nuclear de Carbono-13/métodos , Imageamento por Ressonância Magnética/métodos , Infarto do Miocárdio/diagnóstico por imagem , Miocardite/diagnóstico por imagem , Animais , Isótopos de Carbono/análise , Técnicas de Imagem de Sincronização Cardíaca , Meios de Contraste , Desoxiglucose/metabolismo , Desoxiglucose/farmacologia , Feminino , Glicólise/efeitos dos fármacos , Ácido Láctico/análise , Lipopolissacarídeos/farmacologia , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Imagem Cinética por Ressonância Magnética/métodos , Camundongos , Infarto do Miocárdio/imunologia , Infarto do Miocárdio/metabolismo , Miocardite/imunologia , Miocardite/metabolismo , Miocárdio/imunologia , Miocárdio/metabolismo , Ácido Pirúvico/análise , Células RAW 264.7 , Ratos , Ratos Wistar , SuínosRESUMO
Current cardiovascular magnetic resonance imaging techniques provide an exquisite assessment of the structure and function of the heart and great vessels, but their ability to assess the molecular processes that underpin changes in cardiac function in health and disease is limited by inherent insensitivity. Hyperpolarized magnetic resonance is a new technology which overcomes this limitation, generating molecular contrast agents with an improvement in magnetic resonance signal of up to five orders of magnitude. One key molecule, hyperpolarized [1-13C]pyruvate, shows particular promise for the assessment of cardiac energy metabolism and other fundamental biological processes in cardiovascular disease. This molecule has numerous potential applications of clinical relevance and has now been translated to human use in early clinical studies. This review outlines the principles of hyperpolarized magnetic resonance and key potential cardiovascular applications for this new technology. Finally, we provide an overview of the pipeline for forthcoming hyperpolarized agents and their potential applications in cardiovascular disease.
Assuntos
Isótopos de Carbono/administração & dosagem , Doenças Cardiovasculares/diagnóstico por imagem , Meios de Contraste/administração & dosagem , Imageamento por Ressonância Magnética , Ácido Pirúvico/administração & dosagem , Animais , Doenças Cardiovasculares/metabolismo , Doenças Cardiovasculares/patologia , Metabolismo Energético , Humanos , Miocárdio/metabolismo , Miocárdio/patologia , Valor Preditivo dos Testes , Sobrevivência de TecidosRESUMO
Hypoxia plays a role in many diseases and can have a wide range of effects on cardiac metabolism depending on the extent of the hypoxic insult. Noninvasive imaging methods could shed valuable light on the metabolic effects of hypoxia on the heart in vivo. Hyperpolarized carbon-13 magnetic resonance spectroscopy (HP 13 C MRS) in particular is an exciting technique for imaging metabolism that could provide such information. The aim of our work was, therefore, to establish whether hyperpolarized 13 C MRS can be used to assess the in vivo heart's metabolism of pyruvate in response to systemic acute and chronic hypoxic exposure. Groups of healthy male Wistar rats were exposed to either acute (30 minutes), 1 week or 3 weeks of hypoxia. In vivo MRS of hyperpolarized [1-13 C] pyruvate was carried out along with assessments of physiological parameters and ejection fraction. Hematocrit was elevated after 1 week and 3 weeks of hypoxia. 30 minutes of hypoxia resulted in a significant reduction in pyruvate dehydrogenase (PDH) flux, whereas 1 or 3 weeks of hypoxia resulted in a PDH flux that was not different to normoxic animals. Conversion of hyperpolarized [1-13 C] pyruvate into [1-13 C] lactate was elevated following acute hypoxia, suggestive of enhanced anaerobic glycolysis. Elevated HP pyruvate to lactate conversion was also seen at the one week timepoint, in concert with an increase in lactate dehydrogenase (LDH) expression. Following three weeks of hypoxic exposure, cardiac metabolism of pyruvate was comparable with that observed in normoxia. We have successfully visualized the effects of systemic hypoxia on cardiac metabolism of pyruvate using hyperpolarized 13 C MRS, with differences observed following 30 minutes and 1 week of hypoxia. This demonstrates the potential of in vivo hyperpolarized 13 C MRS data for assessing the cardiometabolic effects of hypoxia in disease.