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[Variability of heart rate].

AIM: The basic principles of the physiological mechanisms of heart rate variability are discussed. The different methods used in its assessm … cant clinical value. RR interval variation is controlled by the activity of cardiac sympathetic and parasympathetic nervous system, the function of which is influenced by many factors such as age, sex, position, breathing, hour of the day, therapeutics, etc. Different methods and results have been used by various authors. Standard values are not yet available to be used or comp …

Stroke-associated pneumonia: major advances and obstacles.

BACKGROUND: Stroke-associated pneumonia (SAP) has been implicated in the morbidity, mortality and increased medical cost after acute ischemic stroke. The annual cost of SAP during hospitalization in the United States approaches USD 459 million. The incidence and prognosis of SAP among intensive care unit (ICU) patients have not been thoroughly investigated. We reviewed the pathophysiology, microbiology, incidence, risk factors, outcomes and prophylaxis of SAP with special attention to ICU studies. METHODS: To determine the incidence, risk factors and prognosis of acute SAP, PubMed was searche

Functional connections between the suprachiasmatic nucleus and the thyroid gland as revealed by lesioning and viral tracing techniques in the rat.

Frequent blood sampling via intraatrial cannula revealed daily rhythms of TSH and thyroid hormones in both male and female Wistar rats. Thermic ablation of the biological clock, i.e. the suprachiasmatic nucleus (SCN), eliminated the diurnal peak in circulating TSH and thyroid hormones. In addition, SCN lesions produced a clear decrease of 24-h mean T4 concentrations. A more pronounced effect of SCN-lesions on thyroid hormones, as opposed to TSH, suggested routes of SCN control additional to the neuroendocrine hypothalamopituitary-thyroid axis. Retrograde, transneuronal virus tracing was used t

Autonomic Imbalance Increases the Risk for Non-alcoholic Fatty Liver Disease.

BACKGROUND: Although autonomic imbalance is associated with an increased risk for metabolic disease, its effects on nonalcoholic fatty liver disease (NAFLD) remains unclear. We aimed to evaluate whether autonomic dysfunction predicts the risk for nonalcoholic fatty liver disease (NAFLD). METHODS: A total of 33,899 participants without NAFLD who underwent health screening programs between 2011 and 2018 were enrolled. NAFLD was identified by ultrasonography. Autonomic activity was estimated using heart rate variability (HRV). Time domain [standard deviation of the normal-to-normal interval (SDN

Differences of sympathetic and parasympathetic modulation in major depression.

Inconsistent results have been reported with respect to cardiac autonomic function in major depression. The aim of our study was to investigate autonomic function in various branches of the autonomic nervous system in order to better understand parasympathetic and sympathetic modulation in the disease. We investigated 29 unmedicated patients suffering from major depression (MD) in comparison to matched control subjects (gender, age, BMI). The autonomic assessment at rest included values of heart rate variability (HRV), blood pressure variability (BPV), baroreflex sensitivity (BRS), respiration

Ginkgo biloba L. extract protects against chronic cerebral hypoperfusion by modulating neuroinflammation and the cholinergic system.

BACKGROUND: Ginkgo biloba extract (GBE)-a widely used nutraceutical-is reported to have diverse functions, including positive effects on memory and vasodilatory properties. Although numerous studies have assessed the neuroprotective properties of GBE in ischemia, only a few studies have investigated the neuro-pharmacological mechanisms of action of GBE in chronic cerebral hypoperfusion (CCH). PURPOSE: In the present study, we sought to determine the effects of GBE on CCH-induced neuroinflammation and cholinergic dysfunction in a rat model of bilateral common carotid artery occlusion (BCCAo).

Cardiovascular variability during periodic leg movements in sleep in children.

STUDY OBJECTIVES: Periodic leg movements in sleep (PLMS) are episodes of repetitive and stereotypic leg movements occurring during sleep. In adults, research indicates that PLMS affects sleep quality and duration and are associated with a shift to relatively greater sympathetic influence over cardiovascular variables. However, little research has been performed to investigate the effect of PLMS episodes on cardiac autonomic control in children. This study aimed to quantify the effect of PLMS episodes during NREM2 sleep on heart rate variability (HRV) measures of sympathovagal balance in childr

The squatting test. A useful tool to assess both parasympathetic and sympathetic involvement of the cardiovascular autonomic neuropathy in diabetes.

The heart rate responses observed after both squatting and standing are thought to be of reflex nature and may be useful to assess the functional integrity of parasympathetic and sympathetic nerves in diabetes. In the standard maneuver, each subject stood still for 3 min, then squatted down for 1 min, and at last stood up during an inspiratory phase. In 10 healthy subjects (25-31 years of age), lengthening of the R-R interval during squatting was abolished by atropine, whereas propranolol markedly attenuated shortening of the R-R interval at standing from squatting. Squatting test (SqT) ratios

The association between concussion and autonomic nervous system responses to a cognitive stressor.

Objective: Investigate the association between concussion and reactivity of cardiovascular, salivary, and electrodermal indicators of autonomic nervous system (ANS) function in the context of cognitive stress. Method: Individuals (N = 37) with concussion were prospectively recruited from a level 1 trauma center emergency department, along with 23 uninjured community controls (UC). Participants were assessed twice (1-week and 1-month post-injury for the concussion group). Electrocardiogram, impedance cardiography, electrodermal skin conductance, and saliva samples were collected before, during,

Anatomy and function of efferent and afferent vagal innervation of the stomach.

The stomach is one of the major targets of the vagus nerve. Vagal cholinergic parasympathetic (efferent) neurons are located in the dorsal motor nucleus of the vagus (DMV) in the caudal brainstem. They do not directly innervate gastric effector cells, but instead a large portion of enteric neurons located in the myenteric plexus, which act as muscle motor neurons and function-specific pattern generators that can regulate specific motility and secretion programs in coordination with physiological needs and environmental conditions. Vagal sensory (afferent) neurons located in the nodose ganglia

A Study on the Spectrum of Autonomic Dysfunction in Primary Central Nervous System Demyelinating Disorders in a Tertiary Care Center from Eastern India.

BACKGROUND AND OBJECTIVES: Primary central nervous system (CNS) demyelinating disorders such as multiple sclerosis (MS), neuromyelitis optica spectrum disorder (NMOSD), myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD), and seronegative longitudinally extensive transverse myelitis (LETM) frequently affect the autonomic nervous system (ANS). Comprehensive data across genitourinary, sudomotor, gastrointestinal, and sexual domains remain limited, especially in Southeast Asian populations. This study aimed to explore the spectrum of autonomic dysfunction in patients with prim

Continuous heart rate variability monitoring, stress and recovery in doctors: a systematic review and meta-analysis.

BACKGROUND: Burnout is a rising concern among doctors. Heart rate variability (HRV), a non-invasive measure of autonomic nervous system activity, can reflect physiological states of sympathetic (stress) and parasympathetic (recovery) nervous system activity. AIMS: This review aims to evaluate how continuous ambulatory HRV monitoring has been used to understand patterns of stress and recovery in doctors. METHODS: The study protocol was preregistered (PROSPERO CRD42023413282). A comprehensive search was conducted. Studies were eligible if they reported at least one HRV parameter combined with

Gut-brain communication: nerve circuits and chemical messengers of colorectal motility and defecation control.

Recent advances and foundational knowledge are integrated to provide a comprehensive description of brain-gut signaling relevant to colorectal motility, with an emphasis on defecation. We discuss molecular targets of therapeutic potential. We identify four levels of neural control: 1) cortical and hypothalamic centers; 2) pontomedullary cell groups; 3) the lumbosacral defecation centers; and 4) the enteric nervous system (ENS). The critical role of central nervous system (CNS) input is evidenced by the constipation that follows spinal cord injury or during Parkinson's disease. The constipation

Effects of Trapezius Muscle Self-Stretching on Muscle Stiffness and Choroidal Circulatory Dynamics: An Evaluation Using Ultrasound Strain Elastography and Laser Speckle Flowgraphy.

BACKGROUND/OBJECTIVES: The relationship between upper trapezius muscle stiffness and choroidal circulatory dynamics remains unclear. This st … CONCLUSIONS: In healthy adults in their 20s and 40s, trapezius muscle self-stretching may enhance parasympathetic nervous system activity, resulting in decreased systemic and choroidal circulatory parameters. However, the reduction in muscle stiffness observed only in younger participants suggests that short-term self-stretching may be less effective in reducing trapezius mus …

Морфологическая и функциональная оценка вагусового нерва при множественном склерозе.

ЦЕЛЬ: Цель этой работы заключается в определении взаимосвязи между поперечным сечением (SAS) вагусовой нервно-паралитической функции и сердечно-сосудистой функцией у людей с множественным склерозом (pwMS) и здоровым контролем (HC). Мы зачислили 50 ПТМС и 50 НС. Все участники прошли ультразвуковой анализ нервной и автономной нервной системы. Хорватский вариант вопросника КОМПАСС-31 использовался в качестве показателя нагрузки на автономию симптомов. Сердечно-сосудистая функция оценивалась с помощью респираторной синусовой аритмии (RSA), Валсалвы (VR) и изменчивости сердечных ритмов. Результаты:

Совпадение в аннотации оригинала
PURPOSE: The aim of this work is to determine the relationship between the cross-sectional area (CSA) of the vagus nerve and cardiovagal fun … ot present in pwMS. CONCLUSIONS: The loss of correlation between vagus nerve CSA and parameters of parasympathetic nervous system function in pwMS corroborates the presence of cardiovagal dysfunction in multiple sclerosis.

The role of the autonomic nervous system in cardiac arrhythmias: The neuro-cardiac axis, more foe than friend?

The autonomic nervous system (ANS) with its two limbs, the sympathetic (SNS) and parasympathetic nervous system (PSNS), plays a critical role in the modulation of cardiac arrhythmogenesis. It can be both pro- and/or anti-arrhythmic at both the atrial and ventricular level of the myocardium. Intricate mechanisms, different for specific cardiac arrhythmias, are involved in this modulatory process. More data are available for the arrhythmogenic effects of the SNS, which, when overactive, can trigger atrial and/or ventricular "adrenergic" arrhythmias in susceptible individuals (e.g. in patients wi…

Quantifying acute physiological biomarkers of transcutaneous cervical vagal nerve stimulation in the context of psychological stress.

BACKGROUND: Stress is associated with activation of the sympathetic nervous system, and can lead to lasting alterations in autonomic function and in extreme cases symptoms of posttraumatic stress disorder (PTSD). Vagal nerve stimulation (VNS) is a potentially useful tool as a modulator of autonomic nervous system function, however currently available implantable devices are limited by cost and inconvenience. OBJECTIVE: The purpose of this study was to assess the effects of transcutaneous cervical VNS (tcVNS) on autonomic responses to stress. METHODS: Using a double-blind approach, we investi

Ultrafine particles and ozone perturb norepinephrine clearance rather than centrally generated sympathetic activity in humans.

Cardiovascular risk rapidly increased following exposure to air pollution. Changes in human autonomic regulation have been implicated based on epidemiological associations between exposure estimates and indirect autonomic nervous system measurements. We conducted a mechanistic study to test the hypothesis that, in healthy older individuals, well-defined experimental exposure to ultrafine carbon particles (UFP) increases sympathetic nervous system activity and more so with added ozone (O3). Eighteen participants (age >50 years, 6 women) were exposed to filtered air (Air), UFP, and UFP + O3 comb

RTL1 promotes melanoma proliferation by regulating Wnt/β-catenin signalling.

OBJECTIVES: Fibromyalgia (FM) is a chronic syndrome characterised by widespread pain, sleep, mood and cognitive disturbances, asthenia and muscle stiffness. The aetiopathogenesis of FM is not fully understood, but autonomic nervous system dysfunction could play a fundamental role in the development of chronic pain and could alter serum levels of neuro-inflammatory mediators like Brain Derived Neurotrophic Factor (BDNF). Transcutaneous vagus nerve stimulation (tVNS) is a non-invasive bioelectronic technique that increases parasympathetic nervous system activity and there is growing evidence tha…