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1.
J Cyst Fibros ; 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38997823

RESUMO

RATIONALE: Cystic Fibrosis (CF) progresses through recurrent infection and inflammation, causing permanent lung function loss and airway remodeling. CT scans reveal abnormally low-density lung parenchyma in CF, but its microstructural nature remains insufficiently explored due to clinical CT limitations. To this end, diffusion-weighted 129Xe MRI is a non-invasive and validated measure of lung microstructure. In this work, we investigate microstructural changes in people with CF (pwCF) relative to age-matched, healthy subjects using comprehensive imaging and analysis involving pulmonary-function tests (PFTs), and 129Xe MRI. METHODS: 38 healthy subjects (age 6-40; 17.2 ± 9.5 years) and 39 pwCF (age 6-40; 15.6 ± 8.0 years) underwent 129Xe-diffusion MRI and PFTs. The distribution of diffusion measurements (i.e., apparent diffusion coefficients (ADC) and morphometric parameters) was assessed via linear binning (LB). The resulting volume percentages of bins were compared between controls and pwCF. Mean ADC and morphometric parameters were also correlated with PFTs. RESULTS: Mean whole-lung ADC correlated significantly with age (P < 0.001) for both controls and CF, and with PFTs (P < 0.05) specifically for pwCF. Although there was no significant difference in mean ADC between controls and pwCF (P = 0.334), age-adjusted LB indicated significant voxel-level diffusion (i.e., ADC and morphometric parameters) differences in pwCF compared to controls (P < 0.05). CONCLUSIONS: 129Xe diffusion MRI revealed microstructural abnormalities in CF lung disease. Smaller microstructural size may reflect compression from overall higher lung density due to interstitial inflammation, fibrosis, or other pathological changes. While elevated microstructural size may indicate emphysema-like remodeling due to chronic inflammation and infection.

2.
Abdom Radiol (NY) ; 49(7): 2408-2415, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38896248

RESUMO

OBJECTIVES: Magnetic resonance (MR) imaging with secretin stimulation (MR-PFTs) is a non-invasive test for pancreatic exocrine function based on assessing the volume of secreted bowel fluid in vivo. Adoption of this methodology in clinical care and research is largely limited to qualitative assessment of secretion as current methods for secretory response quantification require manual thresholding and segmentation of MR images, which can be time-consuming and prone to interrater variability. We describe novel software (PFTquant) that preprocesses and thresholds MR images, performs heuristic detection of non-bowel fluid objects, and provides the user with intuitive semi-automated tools to segment and quantify bowel fluid in a fast and robust manner. We evaluate the performance of this software on a retrospective set of clinical MRIs. METHODS: Twenty MRIs performed in children (< 18 years) were processed independently by two observers using a manual technique and using PFTquant. Interrater agreement in measured secreted fluid volume was compared using intraclass correlation coefficients, Bland-Altman difference analysis, and Dice similarity coefficients. RESULTS: Interrater reliability of measured bowel fluid secretion using PFTquant was 0.90 (0.76-0.96 95% C.I.) with - 4.5 mL mean difference (-39.4-30.4 mL 95% limits of agreement) compared to 0.69 (0.36-0.86 95% C.I.) with - 0.9 mL mean difference (-77.3-75.5 mL 95% limits of agreement) for manual processing. Dice similarity coefficients were better using PFTquant (0.88 +/- 0.06) compared to manual processing (0.85 +/- 0.10) but not significantly (p = 0.11). Time to process was significantly (p < 0.001) faster using PFTquant (412 +/- 177 s) compared to manual processing (645 +/- 305 s). CONCLUSION: Novel software provides fast, reliable quantification of secreted fluid volume in children undergoing MR-PFTs. Use of the novel software could facilitate wider adoption of quantitative MR-PFTs in clinical care and research.


Assuntos
Imageamento por Ressonância Magnética , Software , Humanos , Imageamento por Ressonância Magnética/métodos , Criança , Masculino , Estudos Retrospectivos , Feminino , Reprodutibilidade dos Testes , Adolescente , Pré-Escolar , Interpretação de Imagem Assistida por Computador/métodos , Testes de Função Pancreática/métodos , Lactente , Secretina , Variações Dependentes do Observador , Pâncreas Exócrino/diagnóstico por imagem
3.
Aging Ment Health ; : 1-9, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38738650

RESUMO

OBJECTIVES: Perceived discrimination is associated with racial cognitive health disparities. Links between discrimination and cognitive performance, like working memory, in everyday settings (i.e. ambulatory performance) require investigation. Depressive symptoms may be a mechanism through which discrimination relates to ambulatory working memory. METHOD: Discrimination, retrospective and momentary depressive symptoms/mood, and aggregated and momentary working memory performance among older Black and White adults were examined within the Einstein Aging Study. RESULTS: Racially stratified analyses revealed that discrimination did not relate to Black or White adults' ambulatory working memory. Among Black adults, however, more frequent discrimination was associated with greater retrospectively reported depressive symptoms, which related to more working memory errors across two weeks (indirect effect p < 0.05). This path was not significant among White adults. Links between discrimination and momentary working memory were not explained by momentary reports of depressed mood for Black or White adults. CONCLUSION: Depressive symptoms may play an important role in the link between discrimination and ambulatory working memory among Black adults across extended measurements, but not at the momentary level. Future research should address ambulatory cognition and momentary reports of discrimination and depression to better understand how to minimize cognitive health disparities associated with discrimination.

4.
Psychosom Med ; 86(4): 349-358, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38446714

RESUMO

OBJECTIVE: Sleep quality is an important health-protective factor. Psychosocial factors, including attachment orientation, may be valuable for understanding who is at risk of poor sleep quality and associated adverse health outcomes. High attachment anxiety is reliably associated with adverse health outcomes, whereas high attachment avoidance is associated with adverse health outcomes when co-occurring with poor self-regulatory capacity, indexed by heart rate variability (HRV). We examined the associations between attachment anxiety, attachment avoidance, HRV, and sleep quality. METHODS: Using longitudinal data from a sample of 171 older adults measured four times over 1 year ( M = 66.18 years old; 67.83% women), we separated the between-person variance (which we call "trait") and within-person variance (which we call "state") for attachment anxiety, attachment avoidance, and HRV (via the root mean square of successive differences). Sleep quality was measured with the Pittsburgh Sleep Quality Index. RESULTS: Higher trait attachment anxiety was associated with poorer global sleep quality ( B = 0.22, p = .005). Higher state attachment avoidance was associated with poorer sleep quality ( B = -0.13, p = .01), except for those with higher trait HRV. Higher state attachment anxiety was associated with poorer sleep quality ( B = -0.15, p = .002), except for those with higher or mean trait HRV. Higher trait attachment anxiety was associated with poorer sleep quality ( B = -0.31, p = .02), except for those with higher trait HRV. CONCLUSIONS: High trait HRV mitigated the adverse effects of attachment insecurity on sleep quality. Our results suggest that people with high trait HRV had greater self-regulation capacity, which may enable them to enact emotion regulation strategies effectively.


Assuntos
Ansiedade , Frequência Cardíaca , Apego ao Objeto , Qualidade do Sono , Humanos , Feminino , Frequência Cardíaca/fisiologia , Masculino , Idoso , Ansiedade/fisiopatologia , Pessoa de Meia-Idade , Estudos Longitudinais
5.
Am J Hum Biol ; 36(6): e24051, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38356336

RESUMO

OBJECTIVE: Hydration status and water intake are critical to physiological health. Despite a popular narrative that dehydration impairs cognitive performance, results are mixed in the literature. Therefore, we tested how hydration status was associated with cognitive performance in an ad libitum state over the course of 3 months. METHODS: Data come from a short-term longitudinal study among middle-to-older aged US adults (n = 78) measured three times (207 observations). All participants were scheduled for 8:00 a.m. visits for the baseline, two-week, and 3-month examinations where they completed surveys, neuropsychological tests to measure cognitive performance, anthropometrics, and a blood draw for biomarker analysis. Serum osmolality (Sosm) was measured as a biomarker of hydration status using osmometry. Four cognitive performance tasks were assessed, including inhibition, working memory, cognitive flexibility, and sustained attention. RESULTS: Panel random effects linear regressions demonstrate that there was an inverse association between dehydration and sustained attention, whereas there were no significant relationships between dehydration and inhibition, working memory, and cognitive flexibility. Adults who were dehydrated (defined as Sosm >300 mOsm/kg) performed substantially worse (B = 0.65 z-score; SE = 0.28; p = .020) on the sustained attention task than those who were not dehydrated adjusting for time fixed effects, age, body mass index, sex, and educational attainment. CONCLUSION: This short-term longitudinal study found that dehydration was only associated with poorer performance on a cognitive performance task that required sustained attention. Maintaining adequate hydration may be increasingly important for middle-to-older aged adults to ensure proper cognitive function, particularly as water needs increase in future climatic scenarios.


Assuntos
Atenção , Cognição , Desidratação , Humanos , Desidratação/epidemiologia , Estudos Longitudinais , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Vida Independente/estatística & dados numéricos
6.
Stress Health ; : e3340, 2023 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-37926770

RESUMO

In the context of bereavement, little is known about the mechanisms that differentiate normative adjustment patterns from those that may indicate potential psychopathology. This study aimed to replicate and extend previous work by (1) characterizing the trajectories of depressive symptoms from 3 to 12 months after the loss of a spouse, (2) examining whether (a) childhood maltreatment and attachment style predicted distinct depression trajectories, and (b) different depression trajectories were associated with the risk of prolonged grief at 12 months post-loss. Recently bereaved individuals (N = 175) completed self-report assessments at 3, 4, 6, and 12-months post-loss. Trajectories of depressive symptoms were estimated using group-based trajectory modelling. Four distinct trajectories of depressive symptoms were identified: (1) resilience (minimal/no depression across time points; 45%), (2) moderate depression-improved (alleviated to 'mild' by 12 months; 31%), (3) severe depression-improved (alleviated to 'moderate' by 12 months; 15%), and (4) chronic depression ('severe' symptoms across time points; 9%). Higher childhood maltreatment predicted a greater likelihood of belonging to the 'severe depression-improved' and 'chronic depression' groups than the 'resilient' and 'moderate depression-improved' groups. Widow(er)s with higher attachment anxiety were more likely to belong to the 'severe depression-improved' and 'chronic depression' groups than the 'resilient' group. The trajectory groups with persistent levels of depressive symptoms up until 6 months were more likely to exhibit prolonged grief at 12 months post-loss. Changes from pre-loss functioning cannot be estimated. Our findings provide insight into the early identification of post-loss prolonged grief.

7.
Mitochondrion ; 2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36958676

RESUMO

This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/policies/article-withdrawal.

8.
Eur J Nutr ; 62(4): 1681-1690, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36790579

RESUMO

PURPOSE: Suboptimal hydration has been linked to a variety of adverse health outcomes. Few studies have examined the impact of hydration status on immune function, a plausible physiological mechanism underlying these associations. Therefore, we tested how variation in hydration status was associated with circulating pro-inflammatory cytokine levels and ex vivo lipopolysaccharide (LPS)-stimulated pro-inflammatory cytokine production. METHODS: Blood samples were obtained from a community sample of healthy middle-to-older-aged adults (N = 72). These samples were used to assess serum osmolality, a biomarker of hydration status, and markers of immune function including circulating pro-inflammatory cytokines and stimulated pro-inflammatory cytokine production after 4 and 24 h of incubation with LPS. Multiple linear regressions were used to test the association between serum osmolality (as a continuous variable) and markers of immune function at baseline and after 4 and 24 h adjusting for age, sex, and BMI. These models were re-estimated with serum osmolality dichotomized at the cut-off for dehydration (> 300 mOsm/kg). RESULTS: While not significantly associated with circulating cytokines (B = - 0.03, p = 0.09), serum osmolality was negatively associated with both 4 h (B = - 0.05, p = 0.048) and 24 h (B = - 0.05, p = 0.03) stimulated cytokine production when controlling for age, sex, and BMI. Similarly, dehydration was associated with significantly lower cytokine production at both 4 h (B = - 0.54, p = 0.02) and 24 h (B = - 0.51, p = 0.02) compared to adequate hydration. CONCLUSION: These findings suggest that dehydration may be associated with suppressed immune function in generally healthy middle-to-older aged community-dwelling adults. Further longitudinal research is needed to more clearly define the role of hydration in immune function.


Assuntos
Desidratação , Lipopolissacarídeos , Adulto , Humanos , Pessoa de Meia-Idade , Vida Independente , Citocinas , Biomarcadores , Concentração Osmolar
9.
Psychoneuroendocrinology ; 150: 106024, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36702040

RESUMO

Spousal bereavement is one of the most stressful experiences in adulthood. In a sample of 183 widow(er)s, bereaved about three months prior, we examined the intersection of employment, family income, and health outcomes (proinflammatory marker production, perceived stress, and grief symptoms). Bereaved employees had higher levels of monocyte-stimulated interleukin-6, tumor necrosis factor-α, chemokine ligands 4, and perceived stress than bereaved retirees. We also found an interaction such that family income was positively associated with perceived stress and grief symptoms for employed window(er)s, but not for retirees. These findings align with the reserve capacity model, which states that people at higher levels of socioeconomic status have more psychosocial resources to address psychosocial stressors. Employment likely served as an added psychological and inflammatory burden for all bereaved workers, except those with the highest incomes.


Assuntos
Luto , Humanos , Pesar , Interleucina-6 , Fator de Necrose Tumoral alfa , Emprego , Família/psicologia
10.
Artigo em Inglês | MEDLINE | ID: mdl-36310606

RESUMO

Bone is a living composite material that has the capacity to adapt and respond to both internal and external stimuli. This capacity allows bone to adapt its structure to habitual loads and repair microdamage. Although human bone evolved to adapt to normal physiologic loading (for example from gravitational and muscle forces), these same biological pathways can potentially be activated through other types of external stimuli such as pulsed electromagnetic fields, mechanical vibration, and others. This review summarizes what is currently known about how human bone adapts to various types of external stimuli. We highlight how studies on sports-specific athletes and other exercise interventions have clarified the role of mechanical loading on bone structure. We also discuss clinical scenarios, such as spinal cord injury, where mechanical loading is drastically reduced, leading to rapid bone loss and permanent alterations to bone structure. Finally, we highlight areas of emerging research and unmet clinical need.

11.
Psychosom Med ; 84(6): 679-684, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35420592

RESUMO

OBJECTIVE: Within the field of psychoneuroimmunology, much attention has been given to immune dysregulation and its impact on cognitive functioning. Some of this work has focused on the association between high levels of basal proinflammatory cytokines and poorer performance on measures of executive functioning; however, effect sizes have been quite small in human studies. METHODS: We investigated whether Epstein-Barr virus (EBV) antibody titers, a marker of immune dysregulation related to cellular immunity, may be associated with executive functioning while also attempting to replicate prior studies using two markers of proinflammatory cytokine production (i.e., circulating and lipopolysaccharide [LPS]-stimulated cytokines [interleukin 6, interleukin 1ß, interferon-γ]). A total of 71 community-dwelling adults (mean [standard deviation] age = 60.87 [6.26] years) who were seropositive for EBV infection participated in the study. RESULTS: Findings indicated that greater EBV antibody titers were associated with poorer performance on measures of the executive functions of inhibition ( B = -2.36, standard error = 1.06, p = .028) and cognitive flexibility ( B = -2.89, standard error = 1.13, p = .013) when including circulating and LPS-stimulated cytokines and other relevant covariates (i.e., age, sex, and body mass index) in linear regression analyses. Neither circulating nor LPS-stimulated cytokines were associated with performance on the cognitive tasks in the regression analyses. CONCLUSIONS: These results suggest that EBV antibody titers may be an indicator of immune dysregulation that is more relevant to executive functioning performance than either circulating or stimulated proinflammatory cytokines among community-dwelling adults.


Assuntos
Infecções por Vírus Epstein-Barr , Adulto , Idoso , Cognição/fisiologia , Citocinas , Infecções por Vírus Epstein-Barr/complicações , Função Executiva/fisiologia , Herpesvirus Humano 4 , Humanos , Imunidade Celular , Lipopolissacarídeos/farmacologia , Pessoa de Meia-Idade
12.
Psychosom Med ; 84(1): 29-39, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34419996

RESUMO

OBJECTIVE: Socioeconomic status (SES) remains a robust risk factor for mortality. Various theoretical models postulate that lower SES is associated with higher negative affect, which then initiates a cascade of physiological disturbances that contribute to illness and early mortality. However, few studies have explicitly investigated the interplay between psychological and biological factors in determining SES disparities in mortality. This study examined the role of daily negative affect and cortisol secretion in explaining the SES-mortality link in a large sample of US adults. METHODS: Using data from the Midlife in the United States study (n = 1735, mean [standard deviation] age = 56.40 [12.10] years, 56.4% female), we tested longitudinal associations between SES, daily negative affect, daily cortisol levels, and all-cause mortality 13 years later. Daily negative affect was classified into three clusters reflecting depressive affect, anxiety, and anger. RESULTS: Higher SES was linked to a lower risk of all-cause mortality (hazard ratio = 0.94, 95% confidence interval = 0.90 to 0.97). Furthermore, there was a sequential link between higher SES and lower mortality through lower daily depressive affect and a steeper ("healthier") diurnal cortisol slope (indirect effect = -0.0007, 95% confidence interval = -0.0014 to -0.0002). Daily anxiety and anger were not associated with cortisol levels or mortality (p values > .05). CONCLUSIONS: These findings suggest that daily negative emotional experiences and the hypothalamic-pituitary-adrenal axis functioning may constitute important psychological and physiological pathways underlying the link between SES and all-cause mortality.


Assuntos
Hidrocortisona , Sistema Hipotálamo-Hipofisário , Adulto , Ritmo Circadiano/fisiologia , Depressão , Feminino , Humanos , Hidrocortisona/metabolismo , Sistema Hipotálamo-Hipofisário/metabolismo , Masculino , Pessoa de Meia-Idade , Sistema Hipófise-Suprarrenal/metabolismo , Saliva/metabolismo , Classe Social , Estresse Psicológico/metabolismo , Estados Unidos/epidemiologia
13.
Mitochondrion ; 62: 122-127, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34785262

RESUMO

Poor sleep may impair systemic mitochondrial bioenergetics, but this relationship has not been examined in humans. This study examined associations of self-reported sleep with peripheral blood mononuclear cell (PBMC) bioenergetics in adults. Forty-three participants completed the Pittsburgh Sleep Quality Index from which sleep indices were calculated. PBMCs were analyzed for bioenergetics using extracellular flux analysis. Sleep efficiency was positively correlated with maximal respiration and spare capacity. Lower sleep efficiency and longer sleep duration were associated with lower Bioenergetic Health Index in age-, sex-, and body mass index-adjusted models. Findings indicate that sleep is related to systemic bioenergetic function in humans.


Assuntos
Metabolismo Energético/fisiologia , Leucócitos Mononucleares/fisiologia , Mitocôndrias/metabolismo , Autorrelato , Qualidade do Sono , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
14.
Psychoneuroendocrinology ; 121: 104863, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32950932

RESUMO

BACKGROUND: Empirical and theoretical evidence suggest that because of the co-evolution of the endocrine and immune response systems, different types of stressors may lead to similar levels of physiological activation. The present analyses examined associations between two physiological stress responses: the cortisol response to an acute laboratory stressor and ex vivo lipopolysaccharide (LPS) stimulated inflammatory cytokine production. METHODS: Healthy middle-aged adults (N = 65) completed testing at two appointments, two weeks apart. Blood was collected at each appointment to measure circulating inflammatory cytokine levels and stimulated inflammatory cytokine production after 4 and 24 hours of incubation with LPS. A cumulative standardized composite measure of inflammation was calculated using the cytokines interleukin-6 (IL-6), interleukin-1ß (IL-1ß), and interferon-γ (IFN-γ). At visit two, after the blood draw, participants completed the Trier Social Stress Test (TSST); saliva samples were collected before and after to generate cortisol response curves (area under the curve with respect to ground [AUCG] and increase/decrease [AUCI]). RESULTS: AUCG was significantly associated with stimulated cytokine production at visit 2 after both 4 hours (B = 6.89; p = 0.007) and 24 hours (B = 7.50; p = 0.005) of incubation, controlling for age, sex, and BMI. AUCI was also significantly associated with stimulated cytokine production at visit 2 after 4 hours (B = 6.28; p = 0.004) and 24 hours (B = 6.16; p = 0.007) of incubation, controlling for age, sex, and BMI. Stimulated inflammatory cytokine production was strongly correlated across the two visits (2 weeks apart) after 4 hours of incubation (r = 0.80, p < 0.001) and after 24 hours (r = 0.80, p < 0.001). Within each visit, stimulated cytokine production after 4 hours was significantly correlated with stimulated inflammation at 24 hours (r = 0.93-0.94, p < 0.05) CONCLUSIONS: These results suggest that LPS-stimulated inflammatory cytokine production and the cortisol response to the TSST contain comparable information about acute human physiological stress responses. Moreover, measurement of stimulated cytokines was highly stable across a two-week time period whether measured after 4 or 24 hours of incubation with LPS.


Assuntos
Hidrocortisona/análise , Inflamação/metabolismo , Estresse Psicológico/metabolismo , Idoso , Citocinas/sangue , Feminino , Humanos , Sistema Imunitário/imunologia , Inflamação/sangue , Interleucina-6/sangue , Lipopolissacarídeos/imunologia , Lipopolissacarídeos/farmacologia , Masculino , Pessoa de Meia-Idade , Saliva/química , Fator de Necrose Tumoral alfa/sangue
15.
Pers Relatsh ; 27(3): 652-673, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36685314

RESUMO

The loss of a spouse is associated with a host of negative health outcomes. While bereaved individuals commonly report somatic symptoms, no investigations exist of the association between reactivation of latent Epstein-Barr virus (EBV) and somatic symptoms among this population. Further, how an individual perceives the quality of their lost relationship in retrospect may impact loss outcomes. Among 99 bereaved spouses, elevated EBV antibody titers were associated with somatic symptoms for those who retrospectively reported high or mean levels of relationship satisfaction (RS), but not among those less satisfied. Further, higher RS was associated with greater grief symptoms. This study identifies higher retrospective RS as a possible risk factor for negative physical and mental health outcomes during bereavement.

16.
J Biomech Eng ; 142(1)2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31314886

RESUMO

In this study, a Bayesian optimization (BO) based computational framework is developed to investigate the design of transcatheter aortic valve (TAV) leaflets and to optimize leaflet geometry such that its peak stress under the blood pressure of 120 mmHg is reduced. A generic TAV model is parametrized by mathematical equations describing its 2D shape and its 3D stent-leaflet assembly line. Material properties previously obtained for bovine pericardium (BP) and porcine pericardium (PP) via a combination of flexural and biaxial tensile testing were incorporated into the finite element (FE) model of TAV. A BO approach was employed to investigate about 1000 leaflet designs for each material under the nominal circular deployment and physiological loading conditions. The optimal parameter values of the TAV model were obtained, corresponding to leaflet shapes that can reduce the peak stress by 16.7% in BP and 18.0% in PP, compared with that from the initial generic TAV model. Furthermore, it was observed that while peak stresses tend to concentrate near the stent-leaflet attachment edge, optimized geometries benefit from more uniform stress distributions in the leaflet circumferential direction. Our analysis also showed that increasing leaflet contact area redistributes peak stresses to the belly region contributing to peak stress reduction. The results from this study may inspire new TAV designs that can have better durability.


Assuntos
Próteses Valvulares Cardíacas , Animais , Valva Aórtica , Teorema de Bayes , Bovinos , Suínos
17.
Death Stud ; 44(12): 778-786, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31094661

RESUMO

Childhood maltreatment dysregulates an individual's physiological response to stress, increasing reactivity to stressors across the lifespan. Given the prevalence and impact of bereavement, we examined whether the association between childhood maltreatment and depression was exacerbated by spousal bereavement. We identified an interaction between childhood maltreatment and bereavement using linear regression analysis (B = 0.79, p < .001). A simple slopes test indicated a positive association between childhood maltreatment and depressive symptoms among those who were bereaved (B = 0.86, p < .001), but such association did not emerge among those who were not bereaved (B = 0.06, p = .60).


Assuntos
Experiências Adversas da Infância/psicologia , Experiências Adversas da Infância/estatística & dados numéricos , Atitude Frente a Morte , Transtorno Depressivo/epidemiologia , Transtorno Depressivo/psicologia , Pesar , Cônjuges/psicologia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
18.
Psychosom Med ; 82(1): 2-9, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31634318

RESUMO

OBJECTIVE: Losing a spouse is a distressing life event that can negatively affect both mental and physical health. Stress-induced health consequences often include increased risk of cardiovascular disease and altered immune system functioning marked by increased inflammation. Here, we sought to identify individual difference factors that covary with problematic inflammatory outcomes. METHOD: We measured recently bereaved spouses' (n = 99) propensity to use emotion regulation strategies and peripheral inflammation, as measured by levels of proinflammatory cytokines after ex vivo stimulation of peripheral leukocytes with T-cell agonists. Specifically, we measured participants' use of cognitive reappraisal, an adaptive emotion regulation strategy in many contexts, and expressive suppression, a less adaptive emotion regulation strategy that involves actively inhibiting emotions after already experiencing them. RESULTS: Bereaved spouses who self-reported frequently using expressive suppression as an emotion regulation strategy tended to have a more pronounced inflammatory response, as indexed by higher levels of a composite cytokine index consisting of interleukin (IL) 17A, IL-2, IL-6, tumor necrosis factor α, and interferon-γ (b = 0.042), as well as tumor necrosis factor α (b = 0.083) and interferon-γ (b = 0.098) when analyzed individually. Notably, these associations were observed in both unadjusted and adjusted models, with the latter including known covariates of inflammation and other potential confounding variables. CONCLUSIONS: These findings suggest that bereaved spouses' use of emotion regulation strategies is associated with altered immune functioning, and such a link may be an important biological pathway by which interventions targeting affect may improve immune system-related health outcomes.


Assuntos
Adaptação Psicológica/fisiologia , Luto , Citocinas/sangue , Regulação Emocional/fisiologia , Fenômenos do Sistema Imunitário/fisiologia , Inflamação/sangue , Cônjuges , Idoso , Idoso de 80 Anos ou mais , Feminino , Pesar , Humanos , Individualidade , Masculino , Pessoa de Meia-Idade
19.
J Behav Med ; 43(5): 829-838, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-31754937

RESUMO

Better executive functioning may be associated with more adaptive stress responses than worse executive functioning, potentially due to less propensity for rumination. In this study, we tested the hypothesis that better executive functioning would be associated with decreased total cortisol output (AUCg) and cortisol sensitivity with respect to increase/decrease (AUCi) in response to a stressor, and that this association is mediated by stress task rumination. Participants completed measures of inhibition, updating/monitoring, and cognitive flexibility, a social-evaluative stressor, and a self-report measure of rumination about the stressor. Participants provided saliva samples at six time points to measure cortisol output and sensitivity. Cognitive flexibility was negatively associated with stress task rumination (r = - .30, p < .05); however, this association was no longer significant when adding covariates (i.e., participant age, sex, highest education, and body mass index) to a regression model. Cognitive flexibility was also associated with AUCg (r = - .28, p < .05), while rumination was associated with AUCi in non-adjusted (r = .28, p < .05) and adjusted (b = .81, p < .05) analyses. Furthermore, females demonstrated better cognitive flexibility (r = .26, p < .05) and lower AUCg (r = - .45, p < .05) compared to males. Findings demonstrate the importance of cognitive flexibility and rumination when predicting dynamic measures of stress-induced cortisol over time.


Assuntos
Hidrocortisona , Estresse Psicológico , Índice de Massa Corporal , Função Executiva , Feminino , Humanos , Masculino , Saliva
20.
Psycholog Relig Spiritual ; 11(3): 319-325, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31485287

RESUMO

OBJECTIVE: There is widespread literature linking church attendance to physical health. However, little is known about the association of church attendance and the immune system, particularly during difficult life transitions. This study investigated the association between church attendance and CMV herpes-virus latency by assessing Cytomegalovirus (CMV) IgG antibody titers among bereaved and non-bereaved individuals. METHODS: Participants included 44 bereaved individuals and 44 controls with a mean age of 68 (SD=12.84). CMV herpes-virus latency was measured using CMV IgG antibody titers. Church attendance was measured using three items from the Community Healthy Activities Model Program for Seniors (CHAMPS) Questionnaire. RESULTS: After adjusting for participant's age, gender, education, minority status, weekly alcohol consumption, smoking, depression, body mass index (BMI) and comorbidities, church attendance was associated with lower CMV IgG antibody titers among bereaved and control participants. Further, there was a significant moderating effect of church attendance in the association between bereavement status and CMV IgG antibody titers, so that bereaved individuals attending church were found to have less herpes-virus reactivation (lower CMV IgG antibody titers) when compared to their bereaved counterparts that do not attend church. CONCLUSION: This study demonstrated that church attendance is associated with less herpes-virus reactivation as indexed by lower levels of CMV IgG antibody titers, particularly among the bereaved. Future studies should focus on further understanding the pathways by which church attendance impacts CMV herpes-virus latency during stressful life events, such as bereavement.

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