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1.
Artigo em Inglês | MEDLINE | ID: mdl-38705273

RESUMO

BACKGROUND: Complex models combining impairment-based control assessments with clinical characteristics and biomarkers have been developed to predict asthma exacerbations. The composite Asthma Impairment and Risk Questionnaire (AIRQ) with adjustments for demographics (age, sex, race, body mass index [BMI]) predicts 12-month exacerbation occurrence similarly to these more complex models. OBJECTIVE: To examine whether AIRQ exacerbation prediction is enhanced when models are adjusted for a wider range of clinical characteristics and biomarkers. METHODS: Patients aged ≥12 years completed monthly online surveys regarding exacerbation-related oral corticosteroid use, emergency-department/urgent-care visits, and hospitalizations. Univariate logistic regressions to predict exacerbations were performed with sociodemographics, comorbidities, exacerbation history, lung function, blood eosinophils, immunoglobulin E, and fractional exhaled nitric oxide. Significant (P≤0.05) variables were included in multivariable logistic regressions with and without AIRQ control categories to predict 12-month exacerbations (log odds ratio [OR], 95% Wald confidence interval [CI]). Model performances were compared. RESULTS: Over 12 months, 1070 patients (70% female; mean[SD] age 43.9[19.4] years; 22% non-White; BMI[SD] 30.6[8.7]) completed ≥1 survey (mean[SD] 10.5[2.8]). In the multivariable analysis, AIRQ control category adjusted for significant clinical characteristics and biomarkers was predictive of ≥1 exacerbation: OR(95%CI) not well-controlled vs well-controlled: 1.93(1.41-2.62), very poorly controlled vs well-controlled: 3.81(2.65-5.47). Receiver operating characteristic area under the curve for this more complex model of exacerbation prediction (AUC=0.72) did not differ from AIRQ (AUC=0.70). Models with AIRQ performed better than those without AIRQ (AUC=0.67, P<0.05). CONCLUSION: Costly and time-consuming complex modeling with clinical characteristics and biomarkers does not enhance the strong exacerbation prediction ability of AIRQ.

2.
Med Teach ; : 1-8, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38489473

RESUMO

INTRODUCTION: Clinical reasoning skills are essential for decision-making. Current assessment methods are limited when testing clinical reasoning and management of uncertainty. This study evaluates the reliability, validity and acceptability of Practicum Script, an online simulation-based programme, for developing medical students' clinical reasoning skills using real-life cases. METHODS: In 2020, we conducted an international, multicentre pilot study using 20 clinical cases with 2457 final-year medical students from 21 schools worldwide. Psychometric analysis was performed (n = 1502 students completing at least 80% of cases). Classical estimates of reliability for three test domains (hypothesis generation, hypothesis argumentation and knowledge application) were calculated using Cronbach's alpha and McDonald's omega coefficients. Validity evidence was obtained by confirmatory factor analysis (CFA) and measurement alignment (MA). Items from the knowledge application domain were analysed using cognitive diagnostic modelling (CDM). Acceptability was evaluated by an anonymous student survey. RESULTS: Reliability estimates were high with narrow confidence intervals. CFA revealed acceptable goodness-of-fit indices for the proposed three-factor model. CDM analysis demonstrated good absolute test fit and high classification accuracy estimates. Student survey responses showed high levels of acceptability. CONCLUSION: Our findings suggest that Practicum Script is a useful resource for strengthening students' clinical reasoning skills and ability to manage uncertainty.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38494113

RESUMO

BACKGROUND: National and international asthma guidelines and reports do not include control tools that combine impairment assessment with exacerbation history in one instrument. OBJECTIVE: To analyze the performance of the composite Asthma Impairment and Risk Questionnaire (AIRQ) in assessing both domains of control and predicting exacerbation risk compared with the Global Initiative for Asthma (GINA) 4-question symptom control tool (GINA SCT), Asthma Control Test (ACT), and physician expert opinion (EO) informed by GINA SCT responses and appraisal of GINA-identified risk factors for poor asthma outcomes. METHODS: Multivariable logistic regressions evaluated AIRQ and GINA SCT as predictors of ACT. McNemar's test compared the proportion of patients categorized at baseline as completely or well-controlled by each assessment but with current impairment or previous-year and subsequent-year exacerbations. RESULTS: The analysis included 1064 patients aged 12 years or older; mean (SD) age 43.8 years (19.3); 70% female; 79% White; and 6% Hispanic or Latino. AIRQ and GINA SCT were highly predictive of ACT well-controlled vs not well-controlled and very poorly controlled (receiver operator characteristic area under curve AIRQ = 0.90, GINA SCT = 0.86, P = .03 AIRQ vs GINA SCT) and ACT very poorly controlled vs well-controlled and not well-controlled asthma (receiver operator characteristic area under curve AIRQ = 0.91, GINA SCT = 0.87, P = .01 AIRQ vs GINA SCT). AIRQ rated fewer patients as having completely or well-controlled asthma who had current impairment (P < .01) or with previous-year and subsequent-year exacerbations (P < .001) than did GINA SCT, ACT, and EO. CONCLUSION: AIRQ performs better in assessing both domains of current control and predicting exacerbation risk than do control tools and EO informed by GINA SCT and risk factors for poor asthma outcomes.

4.
Artigo em Inglês | MEDLINE | ID: mdl-38369256

RESUMO

BACKGROUND: The Asthma Impairment and Risk Questionnaire (AIRQ) is a 10-item, yes/no, equally weighted control tool. Lower scores indicate better control. Moreover, 7 impairment items reflect previous 2-week symptoms, and 3 risk items assess previous 12-month exacerbations. The Follow-up AIRQ for use between annual assessments has a 3-month recall period for exacerbation items. OBJECTIVE: To evaluate the responsiveness of the AIRQ over time and identify a minimal important difference (MID). METHODS: The AIRQ longitudinal study data were analyzed from patients with asthma aged 12 years and older. Anchor-based methods assessed differences in AIRQ scores relative to Patient Global Impression of Change, the accepted MIDs for St. George's Respiratory Questionnaire and Asthma Control Test, and exacerbation occurrence over 12 months. Baseline and 12-month data reflected 12-month recall AIRQ scores; Follow-up AIRQ scores were used for 3-, 6-, and 9-month analyses. RESULTS: A total of 1070 patients were included. The Patient Global Impression of Change rating of "much improved" was associated with AIRQ mean score changes from baseline to months 3, 6, 9, and 12 of -2.0, -1.9, -1.9, and -1.8, respectively. The mean AIRQ score change among patients who met the St. George's Respiratory Questionnaire MID (≥4-point decrease) was -1.8 at 6 and 12 months. The AIRQ mean scores decreased from baseline by -2.2 to -2.5 points at months 3, 6, 9, and 12 for patients who met the Asthma Control Test MID (≥ 3-point increase). A 2-point higher baseline AIRQ score was associated with a 1.7 odds ratio of 12-month exacerbation occurrence (95% CI, 1.53-1.89). CONCLUSION: A change score of 2 is recommended as the AIRQ MID.

5.
Mol Metab ; 81: 101895, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38340808

RESUMO

Peptide YY (PYY3-36) is a post-prandially released gut hormone with potent appetite-reducing activity, the mechanism of action of which is not fully understood. Unravelling how this system physiologically regulates food intake may help unlock its therapeutic potential, whilst minimising unwanted effects. Here we demonstrate that germline and post-natal targeted knockdown of the PYY3-36 preferring receptor (neuropeptide Y (NPY) Y2 receptor (Y2R)) in the afferent vagus nerve is required for the appetite inhibitory effects of physiologically-released PYY3-36, but not peripherally administered pharmacological doses. Post-natal knockdown of the Y2R results in a transient body weight phenotype that is not evident in the germline model. Loss of vagal Y2R signalling also results in altered meal patterning associated with accelerated gastric emptying. These results are important for the design of PYY-based anti-obesity agents.


Assuntos
Hormônios Gastrointestinais , Peptídeo YY , Peptídeo YY/fisiologia , Apetite/fisiologia , Nervo Vago , Ingestão de Alimentos
6.
J Allergy Clin Immunol Pract ; 12(4): 882-888, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38316182

RESUMO

Prevention of asthma exacerbations and reduction of systemic corticosteroid burden remain unmet needs in asthma. US asthma guidelines recommend concomitant short-acting ß2-agonist (SABA) and inhaled corticosteroid (ICS) as an alternative reliever at step 2. The Food and Drug Administration approved a pressurized metered-dose inhaler containing albuterol and budesonide for as-needed treatment or prevention of bronchoconstriction and for reducing exacerbation risk in patients with asthma aged ≥18 years. This combination is approved for use as a reliever with or without maintenance therapy, but it is not indicated for maintenance therapy (or for single maintenance and reliever therapy). Intervening with as-needed SABA-ICS during the window of opportunity to reduce inflammation during loss of asthma control can reduce exacerbation risk, by exerting both genomic and nongenomic anti-inflammatory effects. We propose that the use of albuterol-budesonide rather than albuterol as a reliever to manage episodic symptoms driven by acute bronchoconstriction and airway inflammation can improve outcomes. This combination approach, shown to decrease asthma exacerbations and oral corticosteroid burden in patients with moderate-to-severe asthma, represents a paradigm shift for asthma treatment in the United States. Further safety and efficacy studies should provide evidence that this type of reliever should be standard of care.


Assuntos
Antiasmáticos , Asma , Humanos , Adolescente , Adulto , Budesonida/uso terapêutico , Albuterol/uso terapêutico , Etanolaminas/efeitos adversos , Asma/tratamento farmacológico , Asma/induzido quimicamente , Corticosteroides , Administração por Inalação , Inflamação/tratamento farmacológico , Fumarato de Formoterol/uso terapêutico , Broncodilatadores/uso terapêutico
7.
J Asthma Allergy ; 17: 81-87, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38347908

RESUMO

Background: Severe, uncontrolled asthma and asthma exacerbations in children are associated with abnormal lung function and airway development, and increased risk of chronic obstructive lung disease in adulthood. The rationale for this post hoc analysis was to explore the relationship between changes in asthma exacerbation rates and lung function in children treated with dupilumab. Methods: This post hoc analysis included children aged 6 to 11 years with uncontrolled, moderate-to-severe type 2 asthma (blood eosinophils ≥150 cells/µL or fractional exhaled nitric oxide ≥20 ppb) who received dupilumab or placebo in the phase 3 LIBERTY ASTHMA VOYAGE study (NCT02948959). Endpoints were the proportion of patients achieving clinically meaningful improvements (≥5% or ≥10%) in pre-bronchodilator percent-predicted forced expiratory volume in 1 second (ppFEV1) by Week 12, annualized severe asthma exacerbation rates from Week 12-52, and mean change from baseline in ppFEV1 to Week 12. Results: At Week 12 of VOYAGE, 141/236 (60%) of children treated with dupilumab and 57/114 (50%) of children receiving placebo showed improvements of ≥5% in ppFEV1; 106/236 (45%) children receiving dupilumab and 36/114 (32%) receiving placebo achieved improvements in ppFEV1 ≥10%. During the Week 12-52 treatment period, dupilumab vs placebo significantly reduced severe exacerbation rates in all subgroups by 52-60% (all P<0.05). Dupilumab treatment resulted in rapid and sustained improvements in ppFEV1 (Week 12 least squares mean difference [95% CI] vs placebo: 3.54 [0.30, 6.78] percentage points; P=0.03) in children who achieved improvements of ≥5%. Conclusion: Dupilumab vs placebo significantly improved pre-bronchodilator ppFEV1, with a higher proportion of patients achieving a clinically meaningful response at Week 12. Dupilumab also significantly reduced severe exacerbation rates, independent of pre-bronchodilator ppFEV1 response at Week 12. Trial Registration: NCT02948959.

9.
Neuroimage ; 285: 120492, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38070840

RESUMO

BOLD fMRI signal has been used in conjunction with vasodilatory stimulation as a marker of cerebrovascular reactivity (CVR): the relative change in cerebral blood flow (CBF) arising from a unit change in the vasodilatory stimulus. Using numerical simulations, we demonstrate that the variability in the relative BOLD signal change induced by vasodilation is strongly influenced by the variability in deoxyhemoglobin-containing cerebral blood volume (CBV), as this source of variability is likely to be more prominent than that of CVR. It may, therefore, be more appropriate to describe the relative BOLD signal change induced by an isometabolic vasodilation as a proxy of deoxygenated CBV (CBVdHb) rather than CVR. With this in mind, a new method was implemented to map a marker of CBVdHb, termed BOLD-CBV, based on the normalization of voxel-wise BOLD signal variation by an estimate of the intravascular venous BOLD signal from voxels filled with venous blood. The intravascular venous BOLD signal variation, recorded during repeated breath-holding, was extracted from the superior sagittal sinus in a cohort of 27 healthy volunteers and used as a regressor across the whole brain, yielding maps of BOLD-CBV. In the same cohort, we demonstrated the potential use of BOLD-CBV for the normalization of stimulus-evoked BOLD fMRI by comparing group-level BOLD fMRI responses to a visuomotor learning task with and without the inclusion of voxel-wise vascular covariates of BOLD-CBV and the BOLD signal change per mmHg variation in end-tidal carbon dioxide (BOLD-CVR). The empirical measure of BOLD-CBV accounted for more between-subject variability in the motor task-induced BOLD responses than BOLD-CVR estimated from end-tidal carbon dioxide recordings. The new method can potentially increase the power of group fMRI studies by including a measure of vascular characteristics and has the strong practical advantage of not requiring experimental measurement of end-tidal carbon dioxide, unlike traditional methods to estimate BOLD-CVR. It also more closely represents a specific physiological characteristic of brain vasculature than BOLD-CVR, namely blood volume.


Assuntos
Dióxido de Carbono , Imageamento por Ressonância Magnética , Humanos , Imageamento por Ressonância Magnética/métodos , Volume Sanguíneo Cerebral , Encéfalo/fisiologia , Mapeamento Encefálico/métodos , Circulação Cerebrovascular/fisiologia , Oxigênio
10.
Eur J Hosp Pharm ; 31(2): 88-93, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-37879730

RESUMO

OBJECTIVES: The use of parenteral systemic anticancer therapy (SACT) has led to improved cancer survival. A quality assurance (QA) system of the aseptic compounding process is necessary to ensure safe and consistent production of parenteral SACT. This scoping review identifies international evidence and practice relating to QA standards in the preparation of parenteral SACT in healthcare establishments. METHODS: Standards relating to aseptic compounding in hospital pharmacies and literature exploring the aseptic compounding of parenteral SACT were included. Literature relating to the non-aseptic compounding of medicines and records specific to sterile manufacturing in industrial settings were excluded. A search of several electronic databases, trial registries, the grey literature and websites of key European hospital pharmacy groups and accreditation bodies was conducted on 16 March 2022. A narrative discussion was performed by country, and content analysis of articles was conducted. RESULTS: Thirty-seven records were included. Standards reviewed covered the work environment, the preparation process and the safety of the workers who are potentially exposed to hazardous chemicals. It was a common practice to include frequent audits to ensure adherence to standards. Some standards also recommended external inspections to allow for further learnings. Periodic reviews are encouraged to ensure standards maintain relevance. National standards of the countries reviewed were based on international standards, with minor adaptations for local conditions. CONCLUSIONS: The main limitation of this review is that it is limited to countries with a high human development index. The review shows that the use of an internationally recognised standard as a basis for national standards is best practice, and will allow for relevance into the future.


Assuntos
Nutrição Parenteral , Serviço de Farmácia Hospitalar , Humanos , Composição de Medicamentos , Atenção à Saúde
11.
Front Hum Neurosci ; 17: 1303871, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38077183

RESUMO

Gender-affirming hormone replacement therapy (gaHRT) is an important step for many in the gender diverse community, associated with increased quality-of-life and lower self-reported scores of depression and anxiety. However, considering the interactions that the involved sex hormones have on vasculature (with oestrogen and testosterone demonstrating vasodilatory and vasoconstricting properties, respectively), it is important for transgender healthcare research to examine how the manipulation of these hormones interact with cerebrovascular structure and functioning. There is a stark lack of research in this area. This mini-review outlines the research suggesting a vascular impact of these sex hormones using evidence from a range of cohorts (e.g., menopause, polycystic ovary syndrome) and discusses the work that has been done into cerebrovascular changes following gaHRT. Finally, recommendations for future research into cerebrovascular health in transgender cohorts following gaHRT are outlined.

12.
Alzheimers Res Ther ; 15(1): 213, 2023 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-38087383

RESUMO

BACKGROUND: Genome-wide association studies demonstrate that Alzheimer's disease (AD) has a highly polygenic architecture, where thousands of independent genetic variants explain risk with high classification accuracy. This AD polygenic risk score (AD-PRS) has been previously linked to preclinical cognitive and neuroimaging features observed in asymptomatic individuals. However, shared variance between AD-PRS and neurocognitive features are small, suggesting limited preclinical utility. METHODS: Here, we recruited sixteen clinically asymptomatic individuals (mean age 67; range 58-76) with either extremely low / high AD-PRS (defined as at least 2 standard deviations from the wider sample mean (N = 4504; N EFFECTIVE = 90)) with comparable age sex and education level. We assessed group differences in autobiographical memory and T1-weighted structural neuroimaging features. RESULTS: We observed marked reductions in autobiographical recollection (Cohen's d = - 1.66; P FDR = 0.014) and midline structure (cingulate) thickness (Cohen's d = - 1.55, P FDR = 0.05), with no difference in hippocampal volume (P > 0.3). We further confirm the negative association between AD-PRS and cingulate thickness in a larger study with a comparable age (N = 31,966, ß = - 0.002, P = 0.011), supporting the validity of our approach. CONCLUSIONS: These observations conform with multiple streams of prior evidence suggesting alterations in cingulate structures may occur in individuals with higher AD genetic risk. We were able to use a genetically informed research design strategy that significantly improved the efficiency and power of the study. Thus, we further demonstrate that the recall-by-genotype of AD-PRS from wider samples is a promising approach for the detection, assessment, and intervention in specific individuals with increased AD genetic risk.


Assuntos
Doença de Alzheimer , Humanos , Idoso , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/genética , Giro do Cíngulo/diagnóstico por imagem , Estudo de Associação Genômica Ampla , Genótipo , Neuroimagem
13.
Psychol Res Behav Manag ; 16: 4839-4857, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38050640

RESUMO

Loneliness, an established risk factor for both, mental and physical morbidity, is a mounting public health concern. However, the neurobiological mechanisms underlying loneliness-related morbidity are not yet well defined. Here we examined the role of genes and associated DNA risk polymorphic variants that are implicated in loneliness via genetic and epigenetic mechanisms and may thus point to specific therapeutic targets. Searches were conducted on PubMed, Medline, and EMBASE databases using specific Medical Subject Headings terms such as loneliness and genes, neuro- and epigenetics, addiction, affective disorders, alcohol, anti-reward, anxiety, depression, dopamine, cancer, cardiovascular, cognitive, hypodopaminergia, medical, motivation, (neuro)psychopathology, social isolation, and reward deficiency. The narrative literature review yielded recursive collections of scientific and clinical evidence, which were subsequently condensed and summarized in the following key areas: (1) Genetic Antecedents: Exploration of multiple genes mediating reward, stress, immunity and other important vital functions; (2) Genes and Mental Health: Examination of genes linked to personality traits and mental illnesses providing insights into the intricate network of interaction converging on the experience of loneliness; (3) Epigenetic Effects: Inquiry into instances of loneliness and social isolation that are driven by epigenetic methylations associated with negative childhood experiences; and (4) Neural Correlates: Analysis of loneliness-related affective states and cognitions with a focus on hypodopaminergic reward deficiency arising in the context of early life stress, eg, maternal separation, underscoring the importance of parental support early in life. Identification of the individual contributions by various (epi)genetic factors presents opportunities for the creation of innovative preventive, diagnostic, and therapeutic approaches for individuals who cope with persistent feelings of loneliness. The clinical facets and therapeutic prospects associated with the current understanding of loneliness, are discussed emphasizing the relevance of genes and DNA risk polymorphic variants in the context of loneliness-related morbidity.

14.
Front Plant Sci ; 14: 1161165, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37929178

RESUMO

Introduction: Quinoa is a high-value, nutritious crop that performs well in variable environments, marginal soils, and in diverse crop rotations. Quinoa's many attributes make it an ideal crop for supporting human health in global communities and economies. To date, quinoa research has largely focused on traits in adult plants important for enhancing plant phenotypic plasticity, abiotic stress, disease resistance, and yield. Fewer studies have evaluated quinoa seed dormancy and suggest that most modern quinoa varieties have weak or no seed dormancy, and a narrow window of seed viability post-harvest. In other crops, diminished seed dormancy is a major risk factor for preharvest sprouting (PHS; germination on the panicle due to rain prior to harvest) and may also pose a similar risk for quinoa. Methods: This study (1) developed a dormancy screening assay to characterize seed dormancy strength in a large collection of quinoa varieties, (2) investigated if morphological variables including seed coat color, seed coat thickness, seed shape including eccentricity which evaluates the roundness or flatness of a seed, and other agronomic traits like crude protein content and seed moisture, contribute to quinoa seed dormancy, and (3) evaluated the use of a phenetic modeling approach to explore relationships between seed morphology and seed dormancy. Results: Dormancy screening indicated seed dormancy ranges in quinoa varieties from none to strong dormancy. Further, phenetic modeling approaches indicate that seed coat thickness and eccentricity are important morphological variables that impact quinoa seed dormancy strength. Conclusions: While dormancy screening and phenetic modeling approaches do not provide a direct solution to preventing PHS in quinoa, they do provide new tools for identifying dormant varieties as well as morphological variables contributing to seed dormancy.

16.
Saudi Pharm J ; 31(11): 101796, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37822697

RESUMO

Introduction: Acne is a prevalent skin condition that affects numerous adolescents and adults worldwide. The most effective treatment for acne is isotretinoin, but its usage is associated with a wide range of adverse effects, and regular monitoring is necessary. Hence, appropriate usage with awareness of potential side effects is crucial. This study aimed to assess the knowledge and awareness of isotretinoin use and safety among individuals with acne in Saudi Arabia. Methods: A national cross-sectional survey was conducted through an online self-administered questionnaire distributed via social media platforms. The questionnaire consisted of 27 questions in multiple-choice and Likert scale formats, covering demographics, patient awareness of isotretinoin use and side effects, satisfaction with clinical consultation and information provided. Descriptive statistics were used to summarize data. Results: 1315 participants completed the survey, of which most were female (74.1%), single (67.5%), and aged 18-25 years (48.9%). Dryness and teratogenicity were the most commonly known side effects of isotretinoin use (85.5% and 64.9% respectively). However, most participants were unaware of other side effects, such as psychiatric disorders (62.9%), altered liver enzyme concentrations (65.2%), hyperlipidemia (68.1%), anemia (92.4%), and decreased platelet count (96%). Moreover, 36% of sexually active females initiated isotretinoin without contraception. Regarding satisfaction with the information provided during clinical consultation, 63.2% of participants were very satisfied or satisfied. Doctors were the primary source of information (86.8%), followed by the internet (17.8%). Only 45% were informed to avoid blood donation during and after treatment for at least two months. Conclusion: The study highlights the significance of providing patients with comprehensive information about the potential side effects of isotretinoin, including the need to use contraception and avoid blood donation during and after treatment. Effective communication between physicians and patients is critical in ensuring the safe and effective use of isotretinoin.

17.
Exp Physiol ; 108(12): 1500-1515, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37742137

RESUMO

NEW FINDINGS: What is the central question of this study? Gonadal hormones modulate cerebrovascular function while insulin-like growth factor 1 (IGF-1) facilitates exercise-mediated cerebral angiogenesis; puberty is a critical period of neurodevelopment alongside elevated gonadal hormone and IGF-1 activity: but whether exercise training across puberty enhances cerebrovascular function is unkown. What is the main finding and its importance? Cerebral blood flow is elevated in endurance trained adolescent males when compared to untrained counterparts. However, cerebrovascular reactivity to hypercapnia is faster in trained vs. untrained children, but not adolescents. Exercise-induced improvements in cerebrovascular function are attainable as early as the first decade of life. ABSTRACT: Global cerebral blood flow (gCBF) and cerebrovascular reactivity to hypercapnia ( CV R C O 2 ${\mathrm{CV}}{{\mathrm{R}}_{{\mathrm{C}}{{\mathrm{O}}_{\mathrm{2}}}}}$ ) are modulated by gonadal hormone activity, while insulin-like growth factor 1 facilitates exercise-mediated cerebral angiogenesis in adults. Whether critical periods of heightened hormonal and neural development during puberty represent an opportunity to further enhance gCBF and CV R C O 2 ${\mathrm{CV}}{{\mathrm{R}}_{{\mathrm{C}}{{\mathrm{O}}_{\mathrm{2}}}}}$ is currently unknown. Therefore, we used duplex ultrasound to assess gCBF and CV R C O 2 ${\mathrm{CV}}{{\mathrm{R}}_{{\mathrm{C}}{{\mathrm{O}}_{\mathrm{2}}}}}$ in n = 128 adolescents characterised as endurance-exercise trained (males: n = 30, females: n = 36) or untrained (males: n = 29, females: n = 33). Participants were further categorised as pre- (males: n = 35, females: n = 33) or post- (males: n = 24, females: n = 36) peak height velocity (PHV) to determine pubertal or 'maturity' status. Three-factor ANOVA was used to identify main and interaction effects of maturity status, biological sex and training status on gCBF and CV R C O 2 ${\mathrm{CV}}{{\mathrm{R}}_{{\mathrm{C}}{{\mathrm{O}}_{\mathrm{2}}}}}$ . Data are reported as group means (SD). Pre-PHV youth demonstrated elevated gCBF and slower CV R C O 2 ${\mathrm{CV}}{{\mathrm{R}}_{{\mathrm{C}}{{\mathrm{O}}_{\mathrm{2}}}}}$ mean response times than post-PHV counterparts (both: P ≤ 0.001). gCBF was only elevated in post-PHV trained males when compared to untrained counterparts (634 (43) vs. 578 (46) ml min-1 ; P = 0.007). However, CV R C O 2 ${\mathrm{CV}}{{\mathrm{R}}_{{\mathrm{C}}{{\mathrm{O}}_{\mathrm{2}}}}}$ mean response time was faster in pre- (72 (20) vs. 95 (29) s; P ≤ 0.001), but not post-PHV (P = 0.721) trained youth when compared to untrained counterparts. Cardiorespiratory fitness was associated with gCBF in post-PHV youth (r2  = 0.19; P ≤ 0.001) and CV R C O 2 ${\mathrm{CV}}{{\mathrm{R}}_{{\mathrm{C}}{{\mathrm{O}}_{\mathrm{2}}}}}$ mean response time in pre-PHV youth (r2  = 0.13; P = 0.014). Higher cardiorespiratory fitness during adolescence can elevate gCBF while exercise training during childhood primes the development of cerebrovascular function, highlighting the importance of exercise training during the early stages of life in shaping the cerebrovascular phenotype.


Assuntos
Hipercapnia , Fator de Crescimento Insulin-Like I , Masculino , Adulto , Criança , Feminino , Humanos , Adolescente , Exercício Físico/fisiologia , Circulação Cerebrovascular/fisiologia , Hormônios Gonadais
18.
Psychoneuroendocrinology ; 158: 106393, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37774659

RESUMO

Medial temporal lobe (MTL) atrophy is correlated with risk and severity of Alzheimer disease (AD) pathology and cognitive decline. Increasing evidence suggest that oestrogens affect the aging of MTL structures. Here we investigate the relationship between reproductive hormone exposure, polygenic scores for AD risk and oestradiol concentration, MTL anatomy and cognitive performance in postmenopausal women. To this end, we used data from 10,924 female participants in the UK Biobank from whom brain MRI and genetic data were available. We fitted linear regression models to test whether the volume of structures comprising the MTL were predicted by a) timing related to menopause, b) the use and timing of hormone replacement therapy (HRT) and c) polygenic scores for AD risk and oestradiol concentration. Results showed that longer use of HRT was associated with larger parahippocampal volumes (2.53 mm3/year, p = 0.042). A later age of natural menopause, and a longer reproductive span, was associated with larger hippocampal (6.08 and 5.72 mm3/year, p = 0.0006 and 0.0005), parahippocampal (4.17 mm3 and 4.19 mm3/year, p = 0.00006 and 0.00001), amygdala (2.10 and 2.22 mm3/year, p = 0.028 and 0.01) and perirhinal cortical (2.56 and 2.95 mm3/year, p = 0.028 and 0.008) volumes. Superior prospective memory performance was associated with later age at natural menopause, and a longer reproductive span (ß = 0.05 and 0.05 respectively, p = 0.019 and 0.019). Polygenic scores for AD risk and for oestradiol concentration were not associated with MTL volume and did not interact with menopause-related factors to affect MTL structure. Our results suggest that HRT use did not have any detrimental effects on cognition or brain structure, whilst greater exposure to reproductive hormones across time is associated both with slightly larger volumes of specific MTL structures and marginally superior memory performance, independent of genetic risk for AD and genetic predisposition for higher oestradiol levels. However, the clinical utility of maintenance of oestrogens post-menopause for brain health and protection against cognitive decline is curtailed by the small effect sizes observed.


Assuntos
Doença de Alzheimer , Pós-Menopausa , Humanos , Feminino , Duração da Terapia , Lobo Temporal/patologia , Doença de Alzheimer/patologia , Menopausa , Imageamento por Ressonância Magnética , Estrogênios , Estradiol
19.
Clin Exp Psychol ; 9(4): 8-11, 2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37560184

RESUMO

Since 1990, published addiction psychiatry articles have exceeded 11,495. Several from Blum et al. showed the clinical relevance of the Genetic Addiction Risk Severity (GARS) test in identifying risk for reward deficiency behaviors in cohorts from polysubstance and pain clinics, post-surgical bariatrics, and DWI offenders facing prison time. Since Blum et al first published in JAMA (1990) concerning the association of the DRD2 gene polymorphism and severe alcoholism, confirmation has been mixed and controversial. More recently, however, a meta-analysis of 62 studies showed a significant association between DRD2 rs 1800497 and Alcohol Use Disorder (AUD). Other studies from Yale University showed that a haplotype block of the DRD2 gene A1 allele was associated with AUD and heroin dependence. GWAS studies of depression and suicide in 1.2 million veterans confirmed the first psychiatric candidate gene study finding from Blum et al. 1990; a significant association between the minor DRD2 allele, Taq A1 (rs 1800497 C>T) and severe alcoholism. Additionally, the DRD2 rs1800497 is associated with suicide behaviors robustly at P=1.77 × 10-7. Furthermore, DNA polymorphic alleles underlying SUD with multiple substances were mapped via chromatin refolding, revealed that the DRD2 gene and associated polymorphism(s) was the top gene signal (DRD2, P=7.9 × 10-12). Additionally, based on these investigations, we conclude that GWAS should end the controversy about the DRD2 gene being at least one determinant of Reward Deficiency Syndrome (RDS) first reported in the Royal Society of Medicine journaling 1996.

20.
Heliyon ; 9(8): e18943, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37609394

RESUMO

Emerging data suggest that post-traumatic stress disorder (PTSD) arises from disrupted brain default mode network (DMN) activity manifested by dysregulated encephalogram (EEG) alpha oscillations. Hence, we pursued the treatment of combat veterans with PTSD (n = 185) using an expanded form of repetitive transcranial magnetic stimulation (rTMS) termed personalized-rTMS (PrTMS). In this treatment methodology spectral EEG based guidance is used to iteratively optimize symptom resolution via (1) stimulation of multiple motor sensory and frontal cortical sites at reduced power, and (2) adjustments of cortical treatment loci and stimulus frequency during treatment progression based on a proprietary frequency algorithm (PeakLogic, Inc. San Diego) identifying stimulation frequency in the DMN elements of the alpha oscillatory band. Following 4 - 6 weeks of PrTMS® therapy in addition to routine PTSD therapy, veterans exhibited significant clinical improvement accompanied by increased cortical alpha center frequency and alpha oscillatory synchronization. Full resolution of PTSD symptoms was attained in over 50% of patients. These data support DMN involvement in PTSD pathophysiology and suggest a role in therapeutic outcomes. Prospective, sham controlled PrTMS® trials may be warranted to validate our clinical findings and to examine the contribution of DMN targeting for novel preventive, diagnostic, and therapeutic strategies tailored to the unique needs of individual patients with both combat and non-combat PTSD.

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