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1.
ArXiv ; 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38979490

RESUMEN

Purpose: Phosphorus Magnetic Resonance Spectroscopy (31P MRS) enables non-invasive assessment of energy metabolism, yet its application is hindered by sensitivity limitations. To overcome this, often high magnetic fields are used, leading to challenges such as spatial B 1 + inhomogeneity and therefore the need for accurate flip angle determination in accelerated acquisitions with short repetition times T R ) . In response to these challenges, we propose a novel short T R and look-up table-based Double-Angle Method for fast 3D 31P B 1 + mapping (fDAM). Methods: Our method incorporates 3D weighted stack of spiral gradient echo acquisitions and a frequency-selective pulse to enable efficient B 1 + mapping based on the phosphocreatine signal at 7T. Protocols were optimised using simulations and validated through phantom experiments. The method was validated in phantom experiments and skeletal muscle applications using a birdcage 1H/31P volume coil. Results: The results of fDAM were compared to the classical DAM (cDAM). A good correlation (r=0.94) was obtained between the two B 1 + maps. A 3D 31P B 1 + mapping in the human calf muscle was achieved in about 10 min using a birdcage volume coil, with a 20% extended coverage relative to that of the cDAM (24 min). fDAM also enabled the first full brain coverage 31P 3D B 1 + mapping in approx. 10 min using a 1 Tx/ 32 Rx coil. Conclusion: fDAM is an efficient method for 31P 3D B 1 + mapping, showing promise for future applications in rapid 31P MRSI.

2.
Front Psychiatry ; 15: 1365159, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38774436

RESUMEN

Background: Stimulant medication is commonly prescribed as treatment for attention-deficit/hyperactivity disorder (ADHD). While we previously found that short-term stimulant-treatment influences apparent cortical thickness development in an age-dependent manner, it remains unknown whether these effects persist throughout development into adulthood. Purpose: Investigate the long-term age-dependent effects of stimulant medication use on apparent cortical thickness development in adolescents and adults previously diagnosed with ADHD. Methods: This prospective study included the baseline and 4-year follow-up assessment of the "effects of Psychotropic drugs On the Developing brain-MPH" ("ePOD-MPH") project, conducted between June-1-2011 and December-28-2019. The analyses were pre-registered (https://doi.org/10.17605/OSF.IO/32BHF). T1-weighted MR scans were obtained from male adolescents and adults, and cortical thickness was estimated for predefined regions of interest (ROIs) using Freesurfer. We determined medication use and assessed symptoms of ADHD, anxiety, and depression at both time points. Linear mixed models were constructed to assess main effects and interactions of stimulant medication use, time, and age group on regional apparent cortical thickness. Results: A total of 32 male adolescents (aged mean ± SD, 11.2 ± 0.9 years at baseline) and 24 men (aged mean ± SD, 29.9 ± 5.0 years at baseline) were included that previously participated in the ePOD-MPH project. We found no evidence for long-term effects of stimulant medication use on ROI apparent cortical thickness. As expected, we did find age-by-time interaction effects in all ROIs (left prefrontal ROI: P=.002, right medial and posterior ROIs: P<.001), reflecting reductions in apparent cortical thickness in adolescents. Additionally, ADHD symptom severity (adolescents: P<.001, adults: P=.001) and anxiety symptoms (adolescents: P=0.03) were reduced, and more improvement of ADHD symptoms was associated with higher medication use in adults (P=0.001). Conclusion: We found no evidence for long-term effects of stimulant-treatment for ADHD on apparent cortical thickness development in adolescents and adults. The identified age-dependent differences in apparent cortical thickness development are consistent with existing literature on typical cortical development.

3.
ArXiv ; 2024 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-38584615

RESUMEN

Purpose: Recent expert consensus publications have highlighted the issue of poor reproducibility in magnetic resonance spectroscopy (MRS) studies, mainly due to the lack of standardized reporting criteria, which affects their clinical applicability. To combat this, guidelines for minimum reporting standards (MRSinMRS) were introduced to aid journal editors and reviewers in ensuring the comprehensive documentation of essential MRS study parameters. Despite these efforts, the implementation of MRSinMRS standards has been slow, attributed to the diverse nomenclature used by different vendors, the variety of raw MRS data formats, and the absence of appropriate software tools for identifying and reporting necessary parameters. To overcome this obstacle, we have developed the REproducibility Made Easy (REMY) standalone toolbox. Methods: REMY software supports a range of MRS data formats from major vendors like GE (p. file), Siemens (.twix, .rda, .dcm), Philips (.spar/.sdat), and Bruker (.method), facilitating easy data import and export through a user-friendly interface. REMY employs external libraries such as spec2nii and pymapVBVD to accurately read and process these diverse data formats, ensuring compatibility and ease of use for researchers in generating reproducible MRS research outputs. Users can select and import datasets, choose the appropriate vendor and data format, and then generate an MRSinMRS table, log file, and methodological documents in both Latex and PDF formats. Results: REMY effectively populated key sections of the MRSinMRS table with data from all supported file types. In the hardware section, it successfully read and filled in fields for Field Strength [T], Manufacturer Name, and Software Version, covering three of the five required hardware fields. However, it could not input data for RF coil and additional hardware information due to their absence in the files. For the acquisition section, REMY accurately read and populated fields for the pulse sequence name, nominal voxel size, repetition time, echo time, number of acquisitions/excitations/shots, spectral width [Hz], and number of spectral points, significantly contributing to the completion of the Acquisition fields of the table. Furthermore, REMY generates a boilerplate methods text section for manuscripts. Conclusion: This approach reduces effort and obstacles associated with writing and reporting acquisition parameters and should lead to the widespread adoption of MRSinMRS within the MRS community.

4.
Hum Brain Mapp ; 43(15): 4664-4675, 2022 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-35781371

RESUMEN

Prior studies suggest that methylphenidate, the primary pharmacological treatment for attention-deficit/hyperactivity disorder (ADHD), alters functional brain connectivity. As the neurotransmitter systems targeted by methylphenidate undergo significant alterations throughout development, the effects of methylphenidate on functional connectivity may also be modulated by age. Therefore, we assessed the effects of a single methylphenidate challenge on brain network connectivity in stimulant-treatment naïve children and adults with ADHD. We obtained resting-state functional MRI from 50 boys (10-12 years of age) and 49 men (23-40 years of age) with ADHD (DSM IV, all subtypes), before and after an oral challenge with 0.5 mg/kg methylphenidate; and from 11 boys and 12 men as typically developing controls. Connectivity strength (CS), eigenvector centrality (EC), and betweenness centrality (BC) were calculated for the striatum, thalamus, dorsal anterior cingulate cortex (dACC), and prefrontal cortex (PFC). In line with our hypotheses, we found that methylphenidate decreased measures of connectivity and centrality in the striatum and thalamus in children with ADHD, but increased the same metrics in adults with ADHD. Surprisingly, we found no major effects of methylphenidate in the dACC and PFC in either children or adults. Interestingly, pre-methylphenidate, participants with ADHD showed aberrant connectivity and centrality compared to controls predominantly in frontal regions. Our findings demonstrate that methylphenidate's effects on connectivity of subcortical regions are age-dependent in stimulant-treatment naïve participants with ADHD, likely due to ongoing maturation of dopamine and noradrenaline systems. These findings highlight the importance for future studies to take a developmental perspective when studying the effects of methylphenidate treatment.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad , Estimulantes del Sistema Nervioso Central , Metilfenidato , Adulto , Trastorno por Déficit de Atención con Hiperactividad/diagnóstico por imagen , Trastorno por Déficit de Atención con Hiperactividad/tratamiento farmacológico , Encéfalo , Estimulantes del Sistema Nervioso Central/farmacología , Estimulantes del Sistema Nervioso Central/uso terapéutico , Niño , Dopamina , Humanos , Imagen por Resonancia Magnética , Masculino , Metilfenidato/farmacología , Metilfenidato/uso terapéutico , Persona de Mediana Edad , Norepinefrina
5.
Brain Imaging Behav ; 16(2): 680-691, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34524649

RESUMEN

Understanding the neural mechanisms of emotional reactivity in Attention-Deficit/Hyperactivity Disorder (ADHD) may help develop more effective treatments that target emotion dysregulation. In adult ADHD, emotion regulation problems cover a range of dimensions, including emotional reactivity (ER). One important process that could underlie an impaired ER in ADHD might be impaired working memory (WM) processing. We recently demonstrated that taxing WM prior to the exposure of emotionally salient stimuli reduced physiological and subjective reactivity to such cues in heavy drinkers, suggesting lasting effects of WM activation on ER. Here, we investigated neural mechanisms that could underlie the interaction between WM and ER in adult ADHD participants. We included 30 male ADHD participants and 30 matched controls. Participants performed a novel functional magnetic resonance imaging paradigm in which active WM-blocks were alternated with passive blocks of negative and neutral images. We demonstrated group-independent significant main effects of negative emotional images on amygdala activation, and WM-load on paracingulate gyrus and dorsolateral prefrontal cortex activation. Contrary to earlier reports in adolescent ADHD, no impairments were found in neural correlates of WM or ER. Moreover, taxing WM did not alter the neural correlates of ER in either ADHD or control participants. While we did find effects on the amygdala, paCG, and dlPFC activation, we did not find interactions between WM and ER, possibly due to the relatively unimpaired ADHD population and a well-matched control group. Whether targeting WM might be effective in participants with ADHD with severe ER impairments remains to be investigated.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad , Adolescente , Adulto , Emociones , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Memoria a Corto Plazo/fisiología
6.
Dtsch Arztebl Int ; 118(35-36): 587-594, 2021 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-34789369

RESUMEN

BACKGROUND: Metatarsal fractures are among the most common foot and ankle injuries, with an annual incidence of 6.7 per 100 000 persons. Approximately 30% of metatarsal fractures affect the base of the fifth metatarsal bone. Nevertheless, no evidence-based treatment recommendations are available to date. METHODS: The three fracture localizations according to Lawrence and Botte (zone I, proximal to the intermetatarsal joint between the fourth and fifth metatarsal bones; zone II, in the area of the joint; zone III, at the distal end of the joint) are analyzed on the basis of a systematic literature search. Studies were included that compared the treatment of two types of fracture in the same manner, or that compared two different treatments for a single type of fracture. RESULTS: Nine studies compared different treatments of zone I fractures. Two of these were randomized controlled trials (RCTs); in one RCT, patients given functional therapy returned to work much sooner than those treated with immobilization (11 vs. 28 days; p = 0.001), with otherwise similar outcomes. The non-randomized studies revealed a faster return to full function (33 vs. 46 days; p<0.05) with early functional therapy, and similar outcomes for immobilization and surgery. One RCT that compared functional therapy with immobilization for zone II fractures revealed no statistically significant difference. Five studies compared fractures in zones I and II that were treated in the same manner, revealing similar outcomes. One RCT compared surgery and immobilization for zone III fractures: surgery led to statistically significant improvement of the outcome in all of the measured parameters. CONCLUSION: Fractures in zones I and II should be treated with early functional therapy. There seems to be no reason to consider zone I and II fractures as two separate entities, as the outcomes in the two groups are similar. In contrast, fractures in zone III should primarily be treated surgically.


Asunto(s)
Traumatismos del Tobillo , Traumatismos de los Pies , Fracturas Óseas , Huesos Metatarsianos , Traumatismos de los Pies/diagnóstico por imagen , Traumatismos de los Pies/terapia , Fijación Interna de Fracturas , Fracturas Óseas/terapia , Humanos , Huesos Metatarsianos/diagnóstico por imagen , Ensayos Clínicos Controlados Aleatorios como Asunto
7.
Eur J Psychotraumatol ; 12(1): 1880727, 2021 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-33968316

RESUMEN

Background: Posttraumatic stress disorder (PTSD) is associated with dysregulated neural, cortisol, and cardiac stress reactivity and recovery. This understanding is predominantly based on studies in adults applying emotional-cognitive and trauma-related stimuli inducing negative emotions or perceived threat. Despite large numbers of adolescents with PTSD, few studies are available on neurobiological stress reactivity in this population. Moreover, no previous studies investigated neural reactivity to social-evaluative stress. Objective: To investigate functional brain connectivity, cortisol and cardiac reactivity to acute social-evaluative stress, and additional cortisol measures in trauma-exposed adolescents with and without high PTSD symptoms. Method: A speech preparation task to induce acute social-evaluative stress elicited by anticipatory threat, was used in a subsample of the Amsterdam Born Child and their Development (ABCD) birth cohort, consisting of trauma-exposed adolescents with (n = 20) and without (n = 29) high PTSD symptoms. Psychophysiological interaction analyses were performed to assess group differences in functional connectivity of the hippocampus, mPFC and amygdala during social-evaluative stress and recovery, measured by fMRI. Additionally, perceived stress, heart rate and cortisol stress reactivity and recovery, cortisol awakening response and day curve were compared. Results: The stressor evoked significant changes in heart rate and perceived stress, but not cortisol. The PTSD symptom and control groups differed in functional connectivity between the hippocampus and cerebellum, middle and inferior frontal gyrus, and the mPFC and inferior frontal gyrus during social-evaluative stress versus baseline. Mostly, the same patterns were found during recovery versus baseline. We observed no significant group differences in amygdala connectivity, and cortisol and cardiac measures. Conclusions: Our findings suggest threat processing in response to social-evaluative stress is disrupted in adolescents with PTSD symptoms. Our findings are mainly but not entirely in line with findings in adults with PTSD, which denotes the importance to investigate adolescents with PTSD as a separate population.


Antecedentes: El trastorno de estrés postraumático (TEPT) está asociado con la recuperación. Esta comprensión se basa predominantemente en estudios con adultos, que aplican estímulos emocional-cognitivos y relacionados con el trauma que inducen emociones negativas, o percepción de amenaza. A pesar del gran número de adolescentes con TEPT, hay pocos estudios disponibles sobre la reactividad neurobiológica al estrés en esta población. Además, ningún estudio previo ha investigado la reactividad neuronal al estrés socio-evaluativo.Objetivos: Investigar la conectividad cerebral funcional, el cortisol y la reactividad cardíaca al estrés socio-evaluativo, y medidas adicionales de cortisol en adolescentes expuestos a trauma con y sin síntomas elevados de TEPT.Método: Se utilizó una tarea de preparación de discurso para inducir un estrés socio-evaluativo agudo, provocado por la amenaza anticipatoria, en una submuestra del cohorte de nacimiento del Niño nacido en Amsterdam y su Desarrollo (Amsterdam Born Child and their Development, ABCD), que consta de adolescentes expuestos a traumas con (n = 20) y sin (n = 29) síntomas elevados de TEPT. Se realizaron análisis de interacción psicofisiológica para evaluar las diferencias de grupo en la conectividad funcional del hipocampo, mPFC y amígdala durante el estrés socio-evaluativo y la recuperación, medido por fMRI. Además, se compararon el estrés percibido, la frecuencia cardíaca y la reactividad y recuperación del estrés por cortisol, la respuesta del cortisol al despertar, y la curva diurna.Resultados: El estresor provocó cambios significativos en la frecuencia cardíaca y el estrés percibido, pero no del cortisol. Los grupos con síntomas de TEPT y control difirieron en la conectividad funcional entre el hipocampo y el cerebelo, la circunvolución frontal media e inferior, y la mPFC y la circunvolución frontal inferior durante el estrés socio-evaluativo frente al valor inicial. En su mayoría, se encontraron los mismos patrones durante la recuperación frente a la línea de base. No observamos diferencias significativas entre grupos respecto de la conectividad de la amígdala, ni en las medidas de cortisol y cardíacas.Conclusiones: Nuestros hallazgos sugieren que el procesamiento de amenazas en respuesta al estrés socio-evaluativo se encuentra alterado en adolescentes con síntomas de TEPT. Nuestros hallazgos están principalmente, pero no completamente, en línea con los hallazgos en adultos con TEPT, lo que denota la importancia de investigar a adolescentes con TEPT como una población aparte.

8.
J Drugs Dermatol ; 20(5): 498-502, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-33938685

RESUMEN

BACKGROUND: To date no precise data are available for extrusion forces related to the G-prime and G-double-prime of fillers in combination with different 27G and 30G needles. Therefore, the objective of this study was to analyze extrusion forces of various product-needle-combinations containing two different 27G and two different 30G needles in combination with fillers of a wide range of elastic moduli starting from 2.0 – 166.0 Pa. MATERIAL AND METHODS: Four different fillers with the following elastic moduli 1.87, 11.65, 61.80, 165.50 Pa were combined with four different needles: 27G ½”, internal diameter: 0.300 μm; 27G ½”, internal diameter: 0.241 μm; 30G ½”, internal diameter: 0.241 μm and 30G ½“, internal diameter: 0.240 μm. Product-needle-combination were subjected to uni-axial mechanical testing and the respective extrusion force was measured. RESULTS: The results of this study revealed that the G-prime and the G-double-prime of a product are statistically significantly related to their extrusion force, with higher G-prime/G-double-prime products requiring higher extrusion forces. The results additionally revealed that whether the size of the needle was described as 27G or 30G by the respective manufacturer statistically significant differences between the measured extrusion forces were detected. CONCLUSION: Injectors need to be aware that not every 27G/30G needle has the same extrusion force even though the external diameter is similar (27G or 30G); this might additionally influence the ability to withdraw blood during a pre-injection aspiration manoeuvre. J Drugs Dermatol. 20(5): doi:10.36849/JDD.5237.


Asunto(s)
Técnicas Cosméticas , Rellenos Dérmicos/administración & dosificación , Ácido Hialurónico/administración & dosificación , Inyecciones Subcutáneas/instrumentación , Agujas , Rellenos Dérmicos/química , Módulo de Elasticidad , Ácido Hialurónico/química , Inyecciones Subcutáneas/métodos , Reología
9.
Facial Plast Surg ; 37(5): 614-624, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33682916

RESUMEN

The evaluation of neuromodulator treatment outcomes can be performed by noninvasive surface-derived facial electromyography (fEMG) which can detect cumulative muscle fiber activity deep to the skin. The objective of the present study is to identify the most reliable facial locations where the motor unit action potentials (MUAPs) of various facial muscles can be quantified during fEMG measurements. The study population consisted of five males and seven females (31.0 [12.9] years, body mass index of 22.15 [1.6] kg/m2). Facial muscle activity was assessed in several facial regions in each patient for their respective muscle activity utilizing noninvasive surface-derived fEMG. Variables of interest were the average root mean square of three performed muscle contractions (= signal) (µV), mean root mean square between those contraction with the face in a relaxed facial expression (= baseline noise) (µV), and the signal to noise ratio (SNR). A total of 1,709 processed fEMG signals revealed one specific reliable location in each investigated region based on each muscle's anatomy, on the highest value of the SNR, on the lowest value for the baseline noise, and on the practicability to position the sensor while performing a facial expression. The results of this exploratory study may help guiding future researchers and practitioners in designing study protocols and measuring individual facial MUAP when utilizing fEMG. The locations presented herein were selected based on the measured parameters (SNR, signal, baseline noise) and on the practicability and reproducibility of sensor placement.


Asunto(s)
Músculos Faciales , Contracción Muscular , Electromiografía , Femenino , Humanos , Masculino , Reproducibilidad de los Resultados , Relación Señal-Ruido
10.
AIDS ; 35(8): 1221-1228, 2021 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-33710018

RESUMEN

OBJECTIVE: Cross-sectional studies, including one from our NOVICE cohort [Neurological Visual and Cognitive performance in children with treated perinatally acquired HIV (PHIV) compared with matched HIV-negative controls], have revealed that the brains of children with PHIV have lower white matter and grey matter volumes, more white matter hyperintensities (WMH) and poorer white matter integrity. This longitudinal study investigates whether these differences change over time. METHODS: We approached all NOVICE participants to repeat MRI after 4.6 ±â€Š0.3 years, measuring total white matter and grey matter volume, WMH volume and white matter integrity, obtained by T1-weighted, fluid-attenuated inversion recovery (FLAIR) and diffusion tensor imaging (DTI), respectively. We compared rates of change between groups using multivariable linear mixed effects models, adjusted for sex and age at enrolment. We investigated determinants of developmental deviation, and explored associations with cognitive development. RESULTS: Twenty out of 31 (65%) PHIV-positive, and 20 out of 37 (54%) HIV-negative participants underwent follow-up MRI. Groups did not significantly differ in terms of age and sex. Over time, we found no statistically different changes between groups for white matter and WMH volumes, and for white matter integrity (P > 0.1). Total grey matter volume decreased significantly less in PHIV [group∗time 10 ml, 95% confidence interval -1 to 20, P = 0.078], but this difference in rate of change lost statistical significance after additional adjustment for height (group∗time 9 ml, 95% confidence interval -2 to 20, P = 0.112). We found no HIV-associated determinants for potential reduced grey matter pruning, nor associations with cognitive development. CONCLUSION: While using long-term antiretroviral treatment, structural brain development of adolescents growing up with perinatally acquired HIV appears largely normal.


Asunto(s)
Imagen de Difusión Tensora , Infecciones por VIH , Adolescente , Encéfalo/diagnóstico por imagen , Niño , Estudios Transversales , Infecciones por VIH/tratamiento farmacológico , Humanos , Estudios Longitudinales
11.
Eur J Trauma Emerg Surg ; 47(5): 1621-1625, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32036393

RESUMEN

PURPOSE: Triangular fibrocartilage complex (TFCC) lesions have high clinical relevance. Although multiple studies have been done in the past, there is a lack of data after conservative treatment and controversy remains regarding management. The purpose of this study was to compare the outcome of symptomatic TFCC lesions after conservative treatment and arthroscopic debridement. METHODS: Between 2012 and 2017, 33 patients were included. 16 patients were treated conservatively and 17 patients with arthroscopic debridement. The average age was 41 years (range 18-63). The mean follow-up was 22.2 months (range 6-74). Evaluation included pain, range of motion (ROM), grip strength, Disabilities of the Arm, Shoulder, and Hand (DASH) score, Modified Mayo Wrist Score (MMWS), and Purdue Pegboard test. RESULTS: Pain averaged 0.1 (range 0-1) in the conservative group compared to 1.3 (range 0-6) in the arthroscopic group. The mean ROM was 99% for wrist extension, and 100% for flexion and pro-/supination in the conservative group, and 96% for extension and flexion, and 100% for pro-/supination in the arthoscopic group compared to the contralateral side. Grip strength was 88% (range 63-100) in the conservative group versus 89% (range 33-100) in the arthroscopic group. The conservative group reached a DASH score of 16.8 and MMWS of 94.3 compared to 22.1 and 87.2 in the arthroscopic group. The differences were not statistically significant. CONCLUSIONS: Our study demonstrated similar results of conservative compared to arthroscopic treatment. Because conservative treatment was a sufficient and reliable option, we propose it as first-line treatment for TFCC lesions with stable distal radioulnar joint.


Asunto(s)
Fibrocartílago Triangular , Traumatismos de la Muñeca , Adolescente , Adulto , Artroscopía , Tratamiento Conservador , Humanos , Persona de Mediana Edad , Rango del Movimiento Articular , Estudios Retrospectivos , Resultado del Tratamiento , Traumatismos de la Muñeca/terapia , Articulación de la Muñeca , Adulto Joven
12.
Front Psychiatry ; 12: 813518, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35185641

RESUMEN

Sudden cardiac arrest (SCA) is a leading cause of mortality and morbidity in affluent societies, which underscores the need to identify persons at risk. The etiology of SCA is however complex, with predisposing and precipitating factors interacting. Although anxiety and mental stress have been linked to SCA for decades, their precise role and impact remain unclear and the biological underpinnings are insufficiently understood. In this paper, we systematically reviewed various types of observational studies (total n = 20) examining the association between anxiety or mental stress and SCA. Multiple methodological considerations challenged the summarizing and interpretation of the findings. For anxiety, the overall picture suggests that it predisposes for SCA in physically healthy populations (unadjusted OR = 2.44; 95% CI: 1.06-5.59; n = 3). However, in populations at risk for SCA (n = 4), associations were heterogeneous but not significant. Anxiety may partly predispose to SCA by contributing to other risk factors such as cardiovascular disease and diabetes mellitus via mechanisms such as unhealthy lifestyle and metabolic abnormalities. Mental stress appears to precipitate SCA, presumably by more directly impacting on the cardiac ion channels that control the heart's electrical properties. This may lead to ventricular fibrillation, the arrhythmia that underlies SCA. To advance this field of research, experimental studies that unravel the underlying biological mechanisms are deemed important, and most easily designed for mental stress as a precipitating factor because of the short timeframe. These proof-of-concept studies should examine the whole pathway from the brain to the autonomic nervous system, and eventually to cardiac ion channels. Ultimately, such studies may facilitate the identification of persons at risk and the development of novel preventive strategies.

13.
Front Psychiatry ; 12: 780095, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35126199

RESUMEN

Physical exercise affects hippocampal structure and function, but the underlying neural mechanisms and the effects of exercise intensity remain incompletely understood. Therefore, we undertook a comprehensive, multi-modal 3T and 7T MRI randomized controlled trial (Netherlands Trial Register - NL5847) in which we randomized 52 young, non-athletic volunteers to a 12-week low- or high-intensity exercise program. Using state-of-the-art methods, we investigated changes in hippocampal volume, as well as changes in vasculature, neuro-metabolites, and peripheral growth factors as potential underpinnings. Cardiorespiratory fitness improved over time (p < 0.001), but no interaction with exercise intensity was found (p = 0.48). Accordingly, we did not observe significant interactions between exercise condition and time on MRI measures (all p > 0.06). However, we found a significant decrease in right hippocampal volume (p < 0.01), an increase in left hippocampal glutathione (p < 0.01), and a decrease of left hippocampal cerebral blood volume (p = 0.01) over time, regardless of exercise condition. Additional exploratory analyses showed that changes in brain-derived neurotrophic factor (p = 0.01), insulin-like growth-factor (p = 0.03), and dorsal anterior cingulate cortex N-acetyl-aspartate levels (p = 0.01) were positively associated with cardiorespiratory fitness changes. Furthermore, a trend toward a positive association of fitness and gray-matter cerebral blood flow (p = 0.06) was found. Our results do not provide evidence for differential effects between high-intensity (aerobic) and low-intensity (toning) exercise on hippocampal structure and function in young adults. However, we show small but significant effects of exercise on hippocampal volume, neurometabolism and vasculature across exercise conditions. Moreover, our exploratory results suggest that exercise might not specifically only benefit hippocampal structure and function, but rather has a more widespread effect. These findings suggest that, in agreement with previous MRI studies demonstrating moderate to strong effects in elderly and diseased populations, but none to only mild effects in young healthy cohorts, the benefits of exercise on the studied brain measures may be age-dependent and restorative rather than stimulatory. Our study highlights the importance of a multi-modal, whole-brain approach to assess macroscopic and microscopic changes underlying exercise-induced brain changes, to better understand the role of exercise as a potential non-pharmacological intervention.

14.
Psychoradiology ; 1(3): 152-163, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38665807

RESUMEN

Background: Problems with emotional processing are widely reported in individuals with attention-deficit/hyperactivity disorder (ADHD). Although methylphenidate (MPH) effectively alleviates inattention and hyperactivity symptoms in ADHD, its effects on emotional processing and internalizing symptoms have remained elusive. While we previously found that acute MPH administration modulated neural mechanisms underlying emotional processing in an age-dependent manner, the effects of prolonged administration remained unknown. Objectives: Therefore, we investigated: (i) whether prolonged MPH treatment influences neural substrates (amygdala reactivity and connectivity) of emotional processing, and (ii) whether these effects are modulated by age. Methods: The "effects of Psychotropic drugs On Developing brain-MPH" ("ePOD-MPH") randomized controlled trial was a 16-week double-blind, placebo-controlled, multi-center trial with MPH in 50 boys (10-12 years of age) and 49 men (23-40 years of age), all stimulant treatment-naive and diagnosed with ADHD. Participants performed an emotional face-matching task during functional magnetic resonance imaging. We assessed their symptoms of ADHD and internalizing symptoms at baseline, during the trial (8 weeks), and 1 week after the trial end (17 weeks). Results and Conclusions: We did not find effects of prolonged MPH treatment on emotional processing, as measured by amygdala reactivity and connectivity and internalizing symptoms in this trial with stimulant treatment-naive participants. This differs from our findings on emotional processing following acute MPH administration and the effects of prolonged MPH treatment on the dopamine system, which were both modulated by age. Interestingly, prolonged MPH treatment did improve ADHD symptoms, although depressive and anxiety symptoms showed a medication-independent decrease. Furthermore, our data indicate that baseline internalizing symptoms may be used to predict MPH treatment effects on ADHD symptoms, particularly in (male) adults with ADHD.

15.
J Cosmet Dermatol ; 19(11): 2830-2837, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32946624

RESUMEN

BACKGROUND: Most injection techniques utilizing hyaluronic acid-based soft tissue fillers have predictable outcomes at the location injected. However, the temporal region has been identified to have aesthetic effects beyond the temple. AIMS: To identify and quantify the panfacial aesthetic effects of three different temporal injection techniques. PATIENTS/METHODS: The medical records of nine female and five male Caucasian patients with a mean age of 50.9 ± 11.9 years were retrospectively reviewed for the effects of these techniques: supraperiosteal, interfascial, and subdermal. Panfacial effects were evaluated by the semiquantitative assessment of aesthetic scores for the temple volume, the temporal crest visibility, the lateral orbital rim visibility, the position of the eyebrows, the severity of lateral canthal lines, the midfacial volume, and the contour of the jawline. RESULTS: The supraperiosteal injection technique had the greatest influence on improving the temporal volume (25.0%), the temporal crest (33.3%), and the lateral orbital rim visibility (31.0%) scales but had no effects in other facial regions. The interfascial injection technique revealed good effects on improving temporal hollowing (23.3%) but had an even greater effect on the crow's feet (26.8%) and on the position of the eyebrow (33.3%). The subdermal injection technique had its greatest effects in the lower face by improving the contour of the jawline (26.8%) followed by the improvement of the lower cheek fullness scale (14.3%). CONCLUSION: Future injection algorithms could utilize all three injection techniques together as one multi-layer injection approach with a tailored proportion of each technique based on the aesthetic needs of the patient.


Asunto(s)
Técnicas Cosméticas , Envejecimiento de la Piel , Adulto , Cara , Femenino , Humanos , Elevación , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
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