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BACKGROUND: Whole plant senescence represents the final stage in the life cycle of annual plants, characterized by the decomposition of aging organs and transfer of nutrients to seeds, thereby ensuring the survival of next generation. However, the transcriptomic profile of vegetative organs during this death process remains to be fully elucidated, especially regarding the distinctions between natural programmed death and artificial sudden death induced by herbicide. RESULTS: Differential genes expression analysis using RNA-seq in leaves and roots of Arabidopsis thaliana revealed that natural senescence commenced in leaves at 45-52 days after planting, followed by roots initiated at 52-60 days. Additionally, both organs exhibited similarities with artificially induced senescence by glyphosate. Transcription factors Rap2.6L and WKRY75 appeared to serve as central mediators of regulatory changes during natural senescence, as indicated by co-expression networks. Furthermore, the upregulation of RRTF1, exclusively observed during natural death, suggested its role as a regulator of jasmonic acid and reactive oxygen species (ROS) responses, potentially triggering nitrogen recycling in leaves, such as the glutamate dehydrogenase (GDH) shunt. Root senescence was characterized by the activation of AMT2;1 and GLN1;3, facilitating ammonium availability for root-to-shoot translocation, likely under the regulation of PDF2.1. CONCLUSIONS: Our study offers valuable insights into the transcriptomic interplay between phytohormones and ROS during whole plant senescence. We observed distinct regulatory networks governing nitrogen utilization in leaf and root senescence processes. Furthermore, the efficient allocation of energy from vegetative organs to seeds emerges as a critical determinant of population sustainability of annual Arabidopsis.
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Arabidopsis , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Herbicidas , Senescencia de la Planta , Arabidopsis/genética , Arabidopsis/crecimiento & desarrollo , Arabidopsis/efectos de los fármacos , Arabidopsis/metabolismo , Herbicidas/farmacología , Herbicidas/toxicidad , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Senescencia de la Planta/genética , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Hojas de la Planta/crecimiento & desarrollo , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/metabolismo , Raíces de Plantas/genética , Transcriptoma , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismoRESUMEN
PURPOSE: Although the validity of the Epworth Sleepiness Scale (ESS) as an effectiveness measure for sleep apnea treatments such as continuous positive airway pressure (CPAP) has been supported by multiple studies, some researchers continue to challenge it. They suggest that in addition to its impact on relieving patients' daytime sleepiness, CPAP also alters the internal standards patients use to evaluate their sleepiness (i.e., response shift; RS), confounding the meaning of the difference in the ESS scores. We believe an issue yet to be addressed in this debate is that all existing evidence of RS has been obtained through the then-test approach, a retrospective method sensitive to various cognitive mechanisms. Thus, in the current study, we re-examined this issue using the structural equation modeling (SEM) approach, a method that can be directly applied to randomized clinical trial (RCT) data without retrospective measures. METHODS: With the ESS data from two independent RCTs, we conducted cross-sectional and longitudinal measure invariance tests in SEM to examine whether CPAP would lead to RS. RESULTS: The ESS demonstrated cross-sectional and longitudinal scalar invariance against CPAP treatments. Its factorial pattern, loadings, and thresholds were invariant between the treatment and control groups and pre- and post-treatment, supporting the comparability of the observed mean ESS scores across time and groups. CONCLUSION: Our results support the validity of the average difference scores of the ESS for quantifying the effectiveness of CPAP on group-level daytime sleepiness in RCTs with relatively large sample sizes.
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Studies have shown that local (e.g., midseries) items' specific properties, including being isolated from rest of the items, can generate a local distinctiveness effect, enhancing the memory performance for the local items in serial recall or absolute judgments. However, this has not been the case in relative (comparative) judgments. For the first time, the present study found a local distinctiveness effect in comparative judgments by using an opposite-gender name for the midseries item in an otherwise uniformly one-gender name serial list. The reasons for the previous studies' failure to produce this effect in comparative judgments and the present study's success in obtaining it were discussed. The implication of the finding for the item/order information opponent-process theories was also suggested.
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Juicio , Recuerdo Mental , Humanos , Femenino , Masculino , Recuerdo Mental/fisiología , Adulto Joven , Adulto , Aprendizaje Seriado/fisiologíaRESUMEN
Multi-informant studies are popular in social and behavioral science. However, their data analyses are challenging because data from different informants carry both shared and unique information and are often incomplete. Using Monte Carlo Simulation, the current study compares three approaches that can be used to analyze incomplete multi-informant data when there is a distinction between reference and nonreference informants. These approaches include a two-method measurement model for planned missing data (2MM-PMD), treating nonreference informants' reports as auxiliary variables with the full-information maximum likelihood method or multiple imputation, and listwise deletion. The result suggests that 2MM-PMD, when correctly specified and data are missing at random, has the best overall performance among the examined approaches regarding point estimates, type I error rates, and statistical power. In addition, it is also more robust to data that are not missing at random.
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Taiwan has been an aging society since 2018. As a result, long-term care, end-of-life autonomy, and hospice care have received increasing attention. The government of Taiwan promotes home-based healthcare through the National Health Insurance System to enable the efficient utilization of medical resources and reduce overall medical costs. Taiwan's community hospice and palliative care network is expected to serve as the main care model supplementing partial hospitalization and institutional care. In this article, we review the history of and policies related to hospice and palliative care in Taiwan using a literature review and examining Pingtung County as a case study. The implementation of home-based palliative care is also outlined and policy revisions are proposed. The results are intended to provide a reference for healthcare authorities and medical institutions to promote community hospice and palliative care policies. The integrated care model can enhance the capacity of community-based palliative care, support patients receiving palliative care and their family members and caregivers, and ensure physical and psychological comfort for patients. This model contributes to the realization of older adults' preference for dying at home, which is especially pronounced in cultures where traditional Chinese ideas are deeply rooted.
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Cuidados Paliativos al Final de la Vida , Hospitales para Enfermos Terminales , Humanos , Anciano , Cuidados Paliativos/psicología , Taiwán , Hospitales de EnseñanzaRESUMEN
BACKGROUND: Traditional lecture-based medical ethics and law courses deliver knowledge but may not improve students' learning motivation. To bridge this theory-to-practice gap and facilitate students' learning effectiveness, we applied situated-learning theory to design an interdisciplinary court-based learning (CBL) component within the curriculum. Our study aimed to investigate students' learning feedbacks and propose a creative course design. METHODS: A total of 135 fourth-year medical students participated in this course. The CBL component included 1 h of introduction, 1 h of court attendance, and 2 h of interdisciplinary discussion with senior physicians, judges, and prosecutors. After the class, we conducted a survey using a mixed-methods approach to gauge students' perceptions of engagement, performance, and satisfaction. RESULTS: A total of 97 questionnaires were received (72% response rate). Over 70% of respondents were satisfied and felt that the class was useful except for role-playing activities (60%). More than 60% reported a better understanding of the practical applications of medical law. Approximately half (54%) reported less anxiety about medical disputes. 73% reported that the lecture provided awareness of potential medical disputes, and most respondents expressed an interest in medical law courses after the court visit (78%). 80% of the respondents were able to display empathy and apply mediation skills. Qualitative analyses showed that students demonstrated new knowledge, including recognizing the significance of the medical profession, distinguishing the importance of physician-patient communication, having confidence in the fairness of the justice system, and being willing to increase their legal knowledge. CONCLUSIONS: CBL curriculum increases students' learning motivation in strengthening medical professionalism and medical law, develops students' empathy for patients and communication skills, as well as builds up students' trust in the justice system. This novel course design can be applied to teach medical ethics and law.
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Educación de Pregrado en Medicina , Estudiantes de Medicina , Curriculum , Educación de Pregrado en Medicina/métodos , Ética Médica , Humanos , Aprendizaje , Desempeño de PapelRESUMEN
Ordinal missing data are common in measurement equivalence/invariance (ME/I) testing studies. However, there is a lack of guidance on the appropriate method to deal with ordinal missing data in ME/I testing. Five methods may be used to deal with ordinal missing data in ME/I testing, including the continuous full information maximum likelihood estimation method (FIML), continuous robust FIML (rFIML), FIML with probit links (pFIML), FIML with logit links (lFIML), and mean and variance adjusted weight least squared estimation method combined with pairwise deletion (WLSMV_PD). The current study evaluates the relative performance of these methods in producing valid chi-square difference tests ([Formula: see text]) and accurate parameter estimates. The result suggests that all methods except for WLSMV_PD can reasonably control the type I error rates of [Formula: see text] tests and maintain sufficient power to detect noninvariance in most conditions. Only pFIML and lFIML yield accurate factor loading estimates and standard errors across all the conditions. Recommendations are provided to researchers based on the results.
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Investigación Conductal/métodos , Bioestadística/métodos , Interpretación Estadística de Datos , Modelos Estadísticos , HumanosRESUMEN
In measurement invariance testing, when a certain level of full invariance is not achieved, the sequential backward specification search method with the largest modification index (SBSS_LMFI) is often used to identify the source of non-invariance. SBSS_LMFI has been studied under complete data but not missing data. Focusing on Likert-type scale variables, this study examined two methods for dealing with missing data in SBSS_LMFI using Monte Carlo simulation: robust full information maximum likelihood estimator (rFIML) and mean and variance adjusted weighted least squared estimator coupled with pairwise deletion (WLSMV_PD). The result suggests that WLSMV_PD could result in not only over-rejections of invariance models but also reductions of power to identify non-invariant items. In contrast, rFIML provided good control of type I error rates, although it required a larger sample size to yield sufficient power to identify non-invariant items. Recommendations based on the result were provided.
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Proyectos de Investigación , Simulación por Computador , Humanos , Análisis de los Mínimos Cuadrados , Método de Montecarlo , Tamaño de la MuestraRESUMEN
OBJECTIVE: Despite changes to the diagnostic criteria for eating disorders (EDs) in the DSM-5, the current diagnostic system for EDs has limited ability to inform treatment planning and predict outcomes. Our objective was to test the clinical utility of a novel dimensional approach to understanding the structure of ED psychopathology. METHOD: Participants (N = 243; 82.2% women) were community-recruited adults with a DSM-5 ED assessed at baseline, 6-month, and 1-year follow-up. Hierarchical factor analysis was used to identify a joint hierarchical-dimensional structure of eating, mood, and anxiety symptoms. Exploratory structural equation modeling was used to test the ability of the dimensional model to predict outcomes. RESULTS: At the top of the hierarchy, we identified a broad Internalizing factor that reflected diffuse symptoms of eating, mood, and anxiety disorders. Internalizing branched into three subfactors: distress, fear-avoidance (fears of certain stimuli and behaviors to neutralize fears, including ED behaviors designed to reduce fear of weight gain), and body dissatisfaction, which was nested within distress. The lowest level of the hierarchy was characterized by 15 factors. The hierarchical model predicted 60.1% of the variance in outcomes at 6-month follow-up, whereas all DSM eating, mood, and anxiety disorders combined predicted 35.8% of the variance in outcomes. DISCUSSION: A dimensional approach to understanding and diagnosing EDs improved the ability to prospectively predict clinical course above-and-beyond the traditional categorical (DSM-based) approach. Our findings have implications for endeavors to improve the prediction of ED prognosis and course, and to develop more effective trans-diagnostic treatments.
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Trastornos de Ansiedad/diagnóstico , Mecanismos de Defensa , Trastornos de Alimentación y de la Ingestión de Alimentos/clasificación , Trastornos de Alimentación y de la Ingestión de Alimentos/diagnóstico , Psicopatología , Adulto , Afecto , Ansiedad , Manual Diagnóstico y Estadístico de los Trastornos Mentales , Ingestión de Alimentos , Análisis Factorial , Miedo , Femenino , Estudios de Seguimiento , Humanos , Masculino , Reproducibilidad de los ResultadosRESUMEN
Cross-lagged panel models (CLPMs) are widely used to test mediation with longitudinal panel data. One major limitation of the CLPMs is that the model effects are assumed to be fixed across individuals. This assumption is likely to be violated (i.e., the model effects are random across individuals) in practice. When this happens, the CLPMs can potentially yield biased parameter estimates and misleading statistical inferences. This article proposes a model named a random-effects cross-lagged panel model (RE-CLPM) to account for random effects in CLPMs. Simulation studies show that the RE-CLPM outperforms the CLPM in recovering the mean indirect and direct effects in a longitudinal mediation analysis when random effects exist in the population. The performance of the RE-CLPM is robust to a certain degree, even when the random effects are not normally distributed. In addition, the RE-CLPM does not produce harmful results when the model effects are in fact fixed in the population. Implications of the simulation studies and potential directions for future research are discussed.
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Interpretación Estadística de Datos , Modelos Estadísticos , Simulación por Computador , Humanos , Estudios LongitudinalesRESUMEN
OBJECTIVE: Eating disorders (EDs) are associated with substantial morbidity and mortality, yet up to 45% of individuals with EDs never receive treatment for their eating-related problems. This study sought to identify whether comorbidity, suicidality, discrimination, family cohesion, employment status, income, sex, age, marital status, religious belongingness, and ED-specific variables (body mass index and past-year ED diagnoses) were associated with treatment seeking in a nationally representative sample of individuals with EDs (N = 595; 77.8% women; 72.4% ethnic minority). METHOD: Structural equation modeling was used to identify significant predictors of treatment seeking. RESULTS: In the full sample, age was associated with a greater probability of treatment seeking, and men had a lower probability of seeking treatment. No variables were significant predictors of treatment seeking among individuals in Hispanic or Caucasian subgroups. DISCUSSION: To our knowledge, this was the largest study to characterize predictors of treatment seeking in adults with EDs. Results from this study were consistent with existing literature documenting age and sex differences in treatment seeking among adolescents with an ED. Findings suggest a need for improved ED education and outreach-including greater mental health/ED literacy and decreased stigmatization for patients, providers, and the general public-and additional persuasive public-health messages to change community knowledge about treatment options for younger persons and men with EDs.
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Trastornos de Alimentación y de la Ingestión de Alimentos/terapia , Adolescente , Adulto , Femenino , Humanos , Masculino , Adulto JovenRESUMEN
The abuse of ketamine and amphetamine analogs is associated with incidence of hypertension and strokes involving activation of sympathetic activities. Large cerebral arteries at the base of the brain from several species receive dense sympathetic innervation which upon activation causes parasympathetic-nitrergic vasodilation with increased regional blood flow via axo-axonal interaction mechanism, serving as a protective mechanism to meet O2 demand in an acutely stressful situation. The present study was designed to examine effects of ketamine and amphetamine analogs on axo-axonal interaction-mediated neurogenic nitrergic vasodilation in porcine basilar arteries using techniques of blood-vessel myography, patch clamp and two-electrode voltage clamp, and calcium imaging. In U46619-contracted basilar arterial rings, nicotine (100µM) and electrical depolarization of nitrergic nerves by transmural nerve stimulation (TNS, 8Hz) elicited neurogenic nitrergic vasodilations. Ketamine and amphetamine analogs concentration-dependently inhibited nicotine-induced parasympathetic-nitrergic vasodilation without affecting that induced by TNS, nitroprusside or isoproterenol. Ketamine and amphetamine analogs also concentration-dependently blocked nicotine-induced inward currents in Xenopus oocytes expressing α3ß2-nicotinic acetylcholine receptors (nAChRs), and nicotine-induced inward currents as well as calcium influxes in rat superior cervical ganglion neurons. The potency in inhibiting both inward-currents and calcium influxes is ketamine>methamphetamine>hydroxyamphetamine. These results indicate that ketamine and amphetamine analogs, by blocking nAChRs located on cerebral perivascular sympathetic nerves, reduce nicotine-induced, axo-axonal interaction mechanism-mediated neurogenic dilation of the basilar arteries. Chronic abuse of these drugs, therefore, may interfere with normal sympathetic-parasympathetic interaction mechanism resulting in diminished neurogenic vasodilation and, possibly, normal blood flow in the brainstem.
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Anfetaminas/farmacología , Arteria Basilar/efectos de los fármacos , Ketamina/farmacología , Receptores Nicotínicos/fisiología , Vasoconstrictores/farmacología , Animales , Arteria Basilar/metabolismo , Arteria Basilar/fisiología , Calcio/metabolismo , Círculo Arterial Cerebral/efectos de los fármacos , Círculo Arterial Cerebral/fisiología , Técnicas In Vitro , Ketamina/análogos & derivados , Nicotina/farmacología , Oocitos , Ratas Sprague-Dawley , Receptores Nicotínicos/genética , Ganglio Cervical Superior/efectos de los fármacos , Ganglio Cervical Superior/metabolismo , Ganglio Cervical Superior/fisiología , Porcinos , Vasodilatación/efectos de los fármacos , XenopusRESUMEN
PURPOSE: Fuzzy set theory (FST) can improve various aspects of measurement with questionnaires. However, very little is known about how to use FST to measure quality of life (QOL). The main purpose of our study was to find an appropriate fuzzy measure for QOL that, while demonstrating the advantages of FST, can also be compared with mainstream QOL measures, most of which use traditional Likert-type scales. METHODS: Referring to the literature on fuzzy scoring methods, we first revised the measurement scale and scoring method of the traditional WHOQOL-BREF (i.e., a five-point Likert-type scale) to create three versions of a fuzzy WHOQOL-BREF. Then, we examined the psychometric relationships of these three fuzzy measures and the traditional WHOQOL-BREF in a within-subject design. RESULTS: Our results show that a fuzzy-scales weighted-by-membership (FSWM) version of the WHOQOL-BREF is comparable to the traditional WHOQOL-BREF in that it accepts strong invariance and shows almost perfect agreement. It also demonstrates higher reliability and face validity than the traditional WHOQOL-BREF. CONCLUSION: We recommend that future studies examine the use of FSWM to measure QOL.
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Lógica Difusa , Calidad de Vida , Encuestas y Cuestionarios , Interpretación Estadística de Datos , Femenino , Humanos , Masculino , Psicometría , Reproducibilidad de los ResultadosRESUMEN
Medical treatment and narratives are interrelated. We examined this interrelation by evaluating the medical dispute mediation system in Taiwan. We conducted 16 semi-structured interviews with legal and administrative specialists in medical mediation and physicians involved in mediation meetings. The interview data were reproduced into almost verbatim text for coding and analysis. We examined how narratives were discussed in the field of medicine and identified two approaches to narratives. One was the narrative from a patient's storytelling, that is, narrative-based medicine. The other was the narrative of medical staff, which included shared decision-making and decision aids. Discussions of these approaches revolved around the avoidance of conflicts during medical treatment. However, knowing how to handle unsuccessful medical treatment is crucial. By applying polyphony in narratives, physicians can comprehend the role of narratives in unsuccessful medical treatment, helping themselves to practice how to develop narratives to communicate with patients and their surrogates when encountering any difficulty in different stages of medical treatment.
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Past methodological research on mediation analysis mainly focused on situations where all variables were complete and continuous. When issues of categorical data occur combined with missing data, more methodological considerations are involved. Specifically, appropriate decisions need to be made on estimation methods of the indirect effects and on confidence intervals for testing the indirect effects with accommodations of missing data. We compare strategies that address these issues based on a model with a dichotomous mediator, aiming to provide guidelines for researchers facing such challenges in practice.
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Modelos Estadísticos , Proyectos de InvestigaciónRESUMEN
BACKGROUND: Perivascular adipose tissue (PVAT)-derived relaxing factor (PVATRF) significantly regulates vascular tone. Its chemical nature remains unknown. We determined whether palmitic acid methyl ester (PAME) was the PVATRF and whether its release and/or vasorelaxing activity decreased in hypertension. METHODS AND RESULTS: Using superfusion bioassay cascade technique, tissue bath myography, and gas chromatography/mass spectrometry, we determined PVATRF and PAME release from aortic PVAT preparations of Wistar Kyoto rats and spontaneously hypertensive rats. The PVAT of Wistar Kyoto rats spontaneously and calcium dependently released PVATRF and PAME. Both induced aortic vasorelaxations, which were inhibited by 4-aminopyridine (2 mmol/L) and tetraethylammonium 5 and 10 mmol/L but were not affected by tetraethylammonium 1 or 3 mmol/L, glibenclamide (3 µmol/L), or iberiotoxin (100 nmol/L). Aortic vasorelaxations induced by PVATRF- and PAME-containing Krebs solutions were not affected after heating at 70°C but were equally attenuated after hexane extractions. Culture mediums of differentiated adipocytes, but not those of fibroblasts, contained significant PAME and caused aortic vasorelaxation. The PVAT of spontaneously hypertensive rats released significantly less PVATRF and PAME with an increased release of angiotensin II. In addition, PAME-induced relaxation of spontaneously hypertensive rats aortic smooth muscle diminished drastically, which was ameliorated significantly by losartan. CONCLUSIONS: We found that PAME is the PVATRF, causing vasorelaxation by opening voltage-dependent K+ channels on smooth muscle cells. Diminished PAME release and its vasorelaxing activity and increased release of angiotensin II in the PVAT suggest a noble role of PVAT in pathogenesis of hypertension. The antihypertensive effect of losartan is attributed partly to its reversing diminished PAME-induced vasorelaxation.
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Tejido Adiposo/metabolismo , Hipertensión/metabolismo , Palmitatos/metabolismo , Vasodilatadores/metabolismo , 4-Aminopiridina/farmacología , Adipocitos/metabolismo , Tejido Adiposo/efectos de los fármacos , Angiotensina II/metabolismo , Animales , Aorta/efectos de los fármacos , Aorta/metabolismo , Calcio/metabolismo , Células Cultivadas , Endotelio Vascular/efectos de los fármacos , Fibroblastos/metabolismo , Gliburida/farmacología , Hipertensión/tratamiento farmacológico , Losartán/farmacología , Masculino , Péptidos/farmacología , Canales de Potasio con Entrada de Voltaje/metabolismo , Ratas , Ratas Endogámicas SHR , Ratas Endogámicas WKY , Tetraetilamonio/farmacología , Vasodilatación/efectos de los fármacosRESUMEN
Epidemiological studies have found that more physically active older participants have a reduced risk of Alzheimer disease. Based on enriched environment animal models, this effect is considered to result from physical exercise-induced molecular brain changes. This hypothesis has been tested in humans with randomized controlled trials involving physical exercise vs. more sedentary interventions with neuropsychological outcome measures. Fifty-one such randomized controlled trials were identified from Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines with keywords related to physical activity, cognition, and aging supplemented with reference list search. The five most popular executive function measures (each used in ≥8 trials) were meta-analyzed. Digit symbol was the only measure with a significant estimated overall effect size, indicating that physical exercise had a small (0.17) positive effect on change scores. Estimated overall effect sizes for physical exercise on Digit Span backward, Trails B, letter fluency, and Stroop Color-Word Interference time with/without correction were all not significantly different from zero. These results provide weak support for the notion that physical exercise produces molecular brain changes that enhance executive function test scores in older, nonclinical, participants.
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Función Ejecutiva , Terapia por Ejercicio , Anciano , Cognición , Ejercicio Físico , Humanos , Ensayos Clínicos Controlados Aleatorios como AsuntoRESUMEN
Thoracic aortic perivascular adipose tissue (PVAT) is an adipose organ exhibiting similarities to brown adipose tissue (BAT), including cellular morphology and thermogenic gene expression. However, whether the PVAT phenotype is indistinguishable from the BAT phenotype in physiological vasculature remains unclear. We demonstrated that PVAT is distinguishable from classical BAT, given its specific vessel-tone-controlling function. Activating transcription factor 3 (ATF3) is a key factor in hypertension. Compared with wild-type mice, ATF3-deficient (ATF3 -/- ) mice fed a high-fat diet exhibited elevated mean arterial pressure, increased monocyte chemoattractant protein-1 expression and hypertrophy, plus abnormal fatty tissue accumulation in the thoracic aortic PVAT, and enhanced vascular wall tension and vasoconstrictive responses of potassium chloride, U46619, and norepinephrine in isolated aortic rings, which were restored after administration of adeno-associated ATF3 vector. We suggest that PVAT, not BAT, modulates obesity-related vascular dysfunction. ATF3 within PVAT could provide new insights into the pathophysiology of obesity-related cardiovascular diseases.
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The α(7)-nicotinic ACh receptor (α(7)-nAChR) on sympathetic neurons innervating basilar arteries of pigs crossed bred between Landrace and Yorkshire (LY) is known to mediate nicotine-induced, ß-amyloid (Aß)-sensitive nitrergic neurogenic vasodilation. Preliminary studies, however, demonstrated that nicotine-induced cerebral vasodilation in pigs crossbred among Landrace, Yorkshire, and Duroc (LYD) was insensitive to Aß and α-bungarotoxin (α-BGTX). We investigated nAChR subtype on sympathetic neurons innervating LYD basilar arteries. Nicotine-induced relaxation of porcine isolated basilar arteries was examined by tissue bath myography, inward currents on nAChR-expressing oocytes by two-electrode voltage recording, and mRNA and protein expression in the superior cervical ganglion (SCG) and middle cervical ganglion (MCG) by reverse transcription PCR and Western blotting. Nicotine-induced basilar arterial relaxation was not affected by Aß, α-BGTX, and α-conotoxin IMI (α(7)-nAChR antagonists), or α-conotoxin AuIB (α(3)ß(4)-nAChR antagonist) but was inhibited by tropinone and tropane (α(3)-containing nAChR antagonists) and α-conotoxin MII (selective α(3)ß(2)-nAChR antagonist). Nicotine-induced inward currents in α(3)ß(2)-nAChR-expressing oocytes were inhibited by α-conotoxin MII but not by α-BGTX, Aß, or α-conotoxin AuIB. mRNAs of α(3)-, α(7)-, ß(2)-, and ß(4)-subunits were expressed in both SCGs and MCGs with significantly higher mRNAs of α(3)-, ß(2)-, and ß(4)-subunits than that of α(7)-subunit. The Aß-insensitive sympathetic α(3)ß(2)-nAChR mediates nicotine-induced cerebral nitrergic neurogenic vasodilation in LYD pigs. The different finding from Aß-sensitive α(7)-nAChR in basilar arteries of LY pigs may offer a partial explanation for different sensitivities of individuals to Aß in causing diminished cerebral nitrergic vasodilation in diseases involving Aß.