Rationale: Pre-ejection period (PEP) and T-wave amplitude (TWA) have been used to assess sympathetic nervous system (SNS) activity. Here we report two single-blinded, placebo-controlled intravenous (IV) drug application studies in which we pharmacologically modified SNS activity with epinephrine (study 1) as well as dexmedetomidine (alpha2-agonist) and yohimbine (alpha2-antagonist) (study 2). Restricted heart rate (HR) intervals were analyzed to avoid confounding effects of HR changes.
Objective: Study 1 served to replicate previous findings and to validate our approach, whereas study 2 aimed to investigate how modulation of central SNS activity affects PEP and TWA.
Methods: Forty healthy volunteers (58% females) participated in study 1 (between-subject design). Twelve healthy men participated in study 2 (within-subject design). TWA and PEP were derived from ECG and impedance cardiography, respectively.
Results: Epinephrine shortened PEP and induced statistically significant biphasic TWA changes. However, although the two alpha2-drugs significantly affected PEP as expected, no effects on TWA could be detected.
Conclusion: PEP is better suited to reflect SNS activity changes than TWA.
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Sci Rep
January 2025
Department of Chemistry, College of Science, King Saud University, PO Box 2455, Riyadh, 11541, Saudi Arabia.
The ongoing challenge of water pollution necessitates innovative approaches to remove organic contaminants from wastewater. In this work, new two-dimensional S-scheme heterojunction photocatalysts BiO/CdS and MoS/BiO/CdS that are intended for the effective photocatalytic destruction of 4-nitrophenol, a dangerous organic pollutant, are synthesized and characterized. Utilizing a solvothermal method, successfully generated these ternary nanocomposites, which were characterized through various techniques including X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), high resolution transmission electronmicroscopy (HRTEM), Brunauer-Emmett-Telle (BET) and diffuse reflectance spectroscopy (DRS).
View Article and Find Full Text PDFPharmaceuticals (Basel)
January 2025
Department of Translational Research and New Surgical and Medical Technologies in Medicine and Surgery, University of Pisa, 56126 Pisa, Italy.
Psychedelics, historically celebrated for their cultural and spiritual significance, have emerged as potential breakthrough therapeutic agents due to their profound effects on consciousness, emotional processing, mood, and neural plasticity. This review explores the mechanisms underlying psychedelics' effects, focusing on their ability to modulate brain connectivity and neural circuit activity, including the default mode network (DMN), cortico-striatal thalamo-cortical (CSTC) loops, and the relaxed beliefs under psychedelics (REBUS) model. Advanced neuroimaging techniques reveal psychedelics' capacity to enhance functional connectivity between sensory cerebral areas while reducing the connections between associative brain areas, decreasing the rigidity and rendering the brain more plastic and susceptible to external changings, offering insights into their therapeutic outcome.
View Article and Find Full Text PDFRSC Adv
January 2025
Centre for Genetics and Inherited Diseases (CGID), Taibah University Madinah Saudi Arabia.
In present studies, six Schiff bases were prepared, characterized and evaluated for their anti-tumor activity against the colorectal cancer cell line SW-480. The test compounds were characterized by various physico-chemical techniques such as M. P.
View Article and Find Full Text PDFInorg Chem
January 2025
Department of Materials Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, United States.
The Pd-Zn γ-brass phase provides exciting opportunities for synthesizing site-isolated catalysts with precisely controlled Pd active site ensembles. Introducing a third metallic element into the γ-brass lattice further perturbs the catalytic active site ensembles. Here, we introduce coinage metallic elements M (M = Cu, Ag, and Au) into the Pd-Zn γ-brass phase and investigate the site occupation factors of each element in the γ-brass lattice.
View Article and Find Full Text PDFJ Appl Physiol (1985)
January 2025
Department of Medical Education, Paul L Foster School of Medicine, Texas Tech University Health Science Center, El Paso, TX, USA.
There is growing interest in understanding the complex relationship between psychosocial stress and the human gastrointestinal microbiome (GIM). This review explores the potential physiological pathways connecting these two and how they contribute to a pro-inflammatory environment that can lead to the development and progression of the disease. Exposure to psychosocial stress triggers the activation of the sympathetic nervous system (SNS) and hypothalamic-pituitary axis (HPA), leading to various physiological responses essential for survival and coping with the stressor.
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