Search Results (50)

Background/Objectives: The vestibulo-respiratory reflex regulates the tension of the respiratory muscles, which prevents apneas and awakenings during sleep. This study aimed to determine whether functional deficits in the inner ear disturb sleep quality. Methods: We compared sleep parameters in patients with their first episode of acute inner ear deficit (Group A: sudden idiopathic vertigo attack, sudden sensorineural hearing loss), chronic functional inner ear impairment (Group B: chronic peripheral vertigo, permanent hearing loss), and in healthy individuals (Group C). Polygraphy recordings were performed twice, in Group A at the onset of acute otoneurological symptoms and the second time after their withdrawal with an interval of 1 to 13 days, in Group B after 1 to 6 days, and in Group C after 1 to 8 days. Results: In Group A during the symptomatic night, overall and central apnea-hypopnea indices were significantly higher and snoring time was longer. Group A also had higher central apnea-hypopnea index on the first night compared to healthy individuals. In chronic disorders, sleep recordings showed lower autonomic arousal index than in controls or symptomatic nights in Group A. Conclusions: These findings highlight the severity of sleep apnea indicators in Group A. Our results suggest that acute dysfunction of the inner ear substantially impacts central neuronal signaling responsible for regulating normal sleep-related breathing and leads to a deterioration in sleep quality in contrast to individuals with chronic inner ear impairments. It can also be assumed that people with chronic vertigo or hearing loss experience less interrupted sleep than healthy individuals. Full article

This study offers a comparative analysis of preparatory practices in Buddhist meditation, focusing on the Tiantai tradition of medieval China and the Nyingma tradition of tenth-century Tibet. Challenging the view of meditation as solely a mental experience, it highlights the critical role of the body in shaping contemplative training. Drawing on recent Buddhist studies and cultural embodiment theory, the paper argues that preparatory practices are essential stages of psychophysical transformation, not just preliminary steps. The study explores early Chinese Tiantai texts, particularly Zhiyi’s meditation manuals, which present twenty-five preparatory practices involving posture, diet, breath control, and ethical restraint. In parallel, the paper examines Nupchen Sangye Yeshe’s bSam gtan mig sgron from the Tibetan Nyingma tradition, highlighting its emphasis on physical integrity, ritual purity, four supportive conditions, and environmental harmony. While Tiantai sources provide a structured methodology, Nyingma practices integrate these elements within broader tantric and visionary frameworks. The paper concludes that these practices are not only supportive of meditation, but also performative enactments of Buddhist cosmology and ethics, positioning the body as central to meditation’s transformative potential. Full article

Cardiovascular diseases are the leading cause of morbidity and mortality worldwide, underscoring the urgent need for novel therapeutic targets and strategies. The kinase MARK4 (MAP (microtubule-associated proteins)/microtubule affinity-regulating kinase 4) regulates microtubule-associated proteins pivotal for cell polarity, protein stability, and intracellular signaling. Animal models of heart failure revealed elevated MARK4 levels, which correlated with impaired cardiac contractility. However, the involvement of MARK4 and its potential as a molecular drug target has not yet been explored in the myocardium of cardiovascular patients. We investigated the MARK4 mRNA expression in human myocardial biopsies of 152 high-risk cardiovascular patients undergoing cardiac surgery. Comprehensive echocardiography as well as testing for sleep-disordered breathing (SDB), a critical comorbidity in heart failure, were assessed preoperatively. We observed a substantial upregulation of myocardial MARK4 expression in patients with impaired cardiac contractility, resulting in an inverse correlation with the left ventricular ejection fraction. Myocardial MARK4 expression also correlated with echocardiographic E/e’, a central parameter of diastolic dysfunction. Mechanistically, our analyses revealed that MARK4 expression increases in SDB and under hypoxic conditions, as evidenced by significant correlations between myocardial MARK4 expression and factors like mean oxygen saturation, time with oxygen saturation below 90%, and the oxygen desaturation index. Multivariable regression analysis revealed that both left ventricular ejection fraction and mean oxygen saturation were independently associated with dysregulated MARK4 levels, even when controlling for important clinical covariables as potential confounders. Taken together, our findings demonstrate that MARK4 expression is highly increased in the myocardium of cardiovascular high-risk patients, suggesting it is a potential molecular target against cardiovascular diseases. Full article

Congenital Central Hypoventilation Syndrome (CCHS) is a rare disorder that impairs autonomic breathing control, leading to alveolar hypoventilation and sometimes to central apnoea, predominantly during sleep. Patients typically require nocturnal ventilatory support and alarms to prevent life-threatening desaturation events. However, current alarm systems integrated into pulse oximeters do not provide adequate assistance at home. To address these limitations, we developed an assistive device with customizable multisensory stimulation that activates based on the severity and duration of desaturation episodes. In a multicenter clinical trial involving 4 children and 11 young adults with CCHS, we assessed the device’s effectiveness and the role of arousals over three nights: one baseline and two test nights. The results showed that the device significantly improved awakening rates and enabled faster recovery from desaturations in young adults. However, no such improvements were observed in children compared to the baseline. Arousal events and sleep efficiency were unaffected by the device in both groups. These findings suggest that the device can enhance the safety and autonomy of young adults with CCHS but may be more effective in alerting caregivers in pediatric cases than directly waking children. Further studies are needed to refine its application across different age groups, given the limited sample size. Full article

Background/Objectives: Sleep-disordered breathing (SDB) is a primary concern in children’s health. Research suggests that repeated oxygen drops during sleep—common in SDB—may harm the brainstem’s breathing control centres. This damage likely occurs through oxidative stress, inflammation, and cell death, which weaken the brain’s ability to regulate breathing. Over time, these effects could lead to functional changes (e.g., disrupted chemical signalling) and physical damage in critical brain regions, creating a cycle of unstable breathing. However, much of this evidence comes from animal or lab studies, leaving gaps in our understanding of how these mechanisms work in humans. This review synthesises existing research on how breathing disruptions during sleep—particularly episodes of intermittent hypoxia—affect the brain’s ability to control respiration in children and adolescents. Methods: We analysed studies from medical databases PubMed, Scopus, and Web of Science, focusing on how SDB (obstructive or central sleep apnoea) impacts the brain’s respiratory centres in young populations. Animal studies and research involving children on mechanical ventilation were excluded to focus on natural sleep patterns. Results: After removing duplicates, 54 studies remained. Additionally, 43 record were excluded for various reasons. Ultimately, 11 articles were selected for the final analysis, including three that focused on genetic conditions, such as Down syndrome, Prader–Willi syndrome, and Pierre Robin sequence. The findings suggest that repeated oxygen dips during sleep may harm the brainstem’s respiratory control areas, especially during critical developmental stages. This damage could lead to long-term issues, such as unstable breathing, cardiovascular strain, or neurological problems. However, most studies only captured the immediate effects of low oxygen, leaving uncertainty about permanent harm due to a lack of long-term follow-up. Conclusions: Repeated oxygen deprivation during sleep appears to damage the brainstem and disrupt breathing regulation. However, small study sizes and short observation periods limit the strength of these conclusions. Future research should use advanced imaging tools to clarify long-term risks, develop effective treatments, and track children over extended periods. More significantly, longer-term studies are urgently needed to guide clinical care for vulnerable populations. Full article

Spinal interneurons (SpINs) are pivotal to the function of neural circuits, orchestrating motor, sensory, and autonomic functions in the healthy, intact central nervous system. These interneurons (INs) are heterogeneous, with diverse types contributing to various neural systems, including those that control respiratory function. Research in the last few decades has highlighted the complex involvement of SpINs in modulating motor control. SpINs also partake in motor plasticity by aiding in adapting and rewiring neural circuits in response to injury or disease. This plasticity is crucial in the context of spinal cord injury (SCI), where damage often leads to severe and long-term breathing deficits. Such deficits are a leading cause of morbidity and mortality in individuals with SCI, emphasizing the need for effective interventions. This review will focus on SpIN circuits involved in the modulation of breathing and explore current and emerging approaches that leverage SpINs as therapeutic targets to promote respiratory recovery following SCI. Full article

Sudden unexpected death in epilepsy (SUDEP) is a critical concern for individuals suffering from epilepsy, with respiratory dysfunction playing a significant role in its pathology. Fatal seizures are often characterized by central apnea and hypercapnia (elevated CO₂ levels), indicating a failure in ventilatory control. Research has shown that both human epilepsy patients and animal models exhibit a reduced hypercapnic ventilatory response in the interictal (non-seizure) period, suggesting an impaired ability to regulate breathing in response to high CO₂ levels. This review examines the role of central chemoreceptors—specifically the retrotrapezoid nucleus, raphe nuclei, nucleus tractus solitarius, locus coeruleus, and hypothalamus in this pathology. These structures are critical for sensing CO₂ and maintaining respiratory homeostasis. Emerging evidence also implicates neuropeptidergic pathways within these chemoreceptive regions in SUDEP. Neuropeptides like galanin, pituitary adenylate cyclase-activating peptide (PACAP), orexin, somatostatin, and bombesin-like peptides may modulate chemosensitivity and respiratory function, potentially exacerbating respiratory failure during seizures. Understanding the mechanisms linking central chemoreception, respiratory control, and neuropeptidergic signaling is essential to developing targeted interventions to reduce the risk of SUDEP in epilepsy patients. Full article

(1) Background: Respiratory dysfunction is a debilitating consequence of cervical and thoracic spinal cord injury (SCI), resulting from the loss of cortico-spinal drive to respiratory motor networks. This impairment affects both central and peripheral nervous systems, disrupting motor control and muscle innervation, which is essential for effective breathing. These deficits significantly impact the health and quality of life of individuals with SCI. Noninvasive stimulation techniques targeting these networks have emerged as a promising strategy to restore respiratory function. This study systematically reviewed the evidence on noninvasive electrical stimulation modalities targeting respiratory motor networks, complemented by previously unpublished data from our research. (2) Methods: A systematic search of five databases (PubMed, Ovid, Embase, Science Direct, and Web of Science) identified studies published through 31 August 2024. A total of 19 studies involving 194 participants with SCI were included. Unpublished data from our research were also analyzed to provide supplementary insights. (3) Results: Among the stimulation modalities reviewed, spinal cord transcutaneous stimulation (scTS) emerged as a particularly promising therapeutic approach for respiratory rehabilitation in individuals with SCI. An exploratory clinical trial conducted by the authors confirmed the effectiveness of scTS in enhancing respiratory motor performance using a bipolar, 5 kHz-modulated, and 1 ms pulse width modality. However, the heterogeneity in SCI populations and stimulation protocols across studies underscores the need for further standardization and individualized optimization to enhance clinical outcomes. (4) Conclusions: Developing standardized and individualized neuromodulatory protocols, addressing both central and peripheral nervous system impairments, is critical to optimizing respiratory recovery and advancing clinical implementation. Full article

Background and Objectives: The aim of this study was to investigate the immediate and long-term effects of breathing exercises on simple and choice reaction time. Materials and Methods: A total of 31 participants were included in the study. The participants were randomly divided into two groups. The intervention group (IG; n:16) received 12 sessions of breathing exercises for four weeks (three days a week), while the control group (CG; n:15) received no intervention. Both groups underwent the same assessments at the same times: at baseline, after the first exercise session, and after four weeks/after 12 exercise sessions. Reaction time was assessed using three conditions: choice reaction time (CRT) of the upper limb, auditory reaction time (ART), and visual reaction time (VRT) tests. The first assessment was applied at baseline. The second assessment measured the short-term effect of the breathing exercises after the study group received their first breathing exercise session. The third assessment, to determine the long-term effect, was repeated four weeks after the baseline (A4W) assessment after completing 12 breathing exercises. Results: There was no significant difference between the groups at baseline, immediately, and A4W (p < 0.05) for the VRT, ART, and CRT results with the dominant hand (DH), whereas a group-by-time interaction was found only for the visual reaction time results with the non-dominant hand (nDH) (p > 0.05). Conclusions: The results of this study, which included the evaluation of the immediate and long-term effects of breathing exercises on reaction time, showed an improvement in visual reaction time between the groups over time. In further studies, it is recommended to evaluate the changes and responses in the central nervous system with objective methods to reveal the effect of breathing exercises on reaction time more clearly. Full article

Background: Many COVID-19 survivors still experience long-term effects of an acute infection, most often characterised by neurological, cognitive and psychiatric sequelae. The treatment of this condition is challenging, and many hypotheses have been proposed. Non-invasive vagus nerve stimulation using slow-paced breathing (SPB) could stimulate both central nervous system areas and parasympathetic autonomic pathways, leading to neuromodulation and a reduction in inflammation. The aim of the present study was to evaluate physical, cognitive, emotional symptoms, executive functions and autonomic cardiac modulation after one month of at-home slow breathing intervention. Methods: 6655 healthcare workers (HCWs) were contacted via a company email in November 2022, of which N = 58 HCWs were enrolled as long COVID (cases) and N = 53 HCWs as controls. A baseline comparison of the two groups was performed. Subsequently each case was instructed on how to perform a resonant SPB using visual heart rate variability (HRV) biofeedback. They were then given a mobile video tutorial breathing protocol and asked to perform it three times a day (morning, early afternoon and before sleep). N = 33 cases completed the FU. At T0 and T1, each subject underwent COVID-related, psychosomatic and dysfunctional breathing questionnaires coupled with heart rate variability and manual dexterity assessments. Results: After one month of home intervention, an overall improvement in long-COVID symptoms was observed: confusion/cognitive impairment, chest pain, asthenia, headache and dizziness decreased significantly, while only a small increase in manual dexterity was found, and no relevant changes in cardiac parasympathetic modulation were observed. Full article

Background and Objectives: Obstructive sleep apnea (OSA) is a prevalent sleep-disordered breathing pathology with significant clinical consequences, including increased cardiovascular risk and cognitive decline. Continuous positive airway pressure (CPAP) is the gold-standard treatment, but alternative strategies are sometimes needed for patients intolerant to CPAP. Drug-induced sleep endoscopy (DISE) is a key diagnostic tool for assessing upper airway obstruction in OSA patients and subsequently tailoring a surgical approach, with sedation protocols playing a crucial role in its efficacy and results accuracy. This study aimed to investigate the effect of adding remifentanil to a propofol target-controlled infusion (TCI) regimen on the sedation parameters and procedural outcomes of DISE. Materials and Methods: The study was conducted at the Central University and Emergency Military Hospital “Dr. Carol Davila” and Ria Clinic in Bucharest between July 2021 and October 2023. Thirty-one patients were enrolled and randomised into two groups: a propofol group (P group, n= 11) and a remifentanil-propofol group (R-P group, n = 20). DISE was performed using standardised protocols, sedative drugs were administered in TCI mode, and data on sedation levels, respiratory and cardiovascular parameters, and procedural incidents were collected. Results: The addition of remifentanil at 1 ng/mL effect-site concentration significantly reduced the effect-site concentration of propofol required for adequate sedation (3.4 ± 0.7 µg/mL in the P group vs. 2.8 ± 0.6 µg/mL in the R-P group, p = 0.035). The time to achieve adequate sedation was also shorter in the R-P group (7.1 ± 2.5 min vs. 9.5 ± 2.7 min, p = 0.017). The incidence of cough, hypoxemia, and cardiovascular events did not significantly differ between the two groups. Conclusions: Adding remifentanil to a propofol TCI regimen for DISE effectively reduces the required propofol effect-site concentration and shortens sedation time without increasing the risk of adverse events. This combination may enhance the safety and efficiency of DISE, offering a promising alternative for patients undergoing this procedure. Full article

Background: Pulmonary involvement in systemic juvenile idiopathic arthritis (SJIA) is a rare but dangerous complication. The main risk factors are already known, such as macrophage activation syndrome, a refractory course of systemic juvenile arthritis, infusion reaction to interleukin 1 and/or interleukin 6 blockers, trisomy 21, and eosinophilia. However, information about respiratory system involvement (RSI) at the onset of SJIA is scarce. Our study aimed to evaluate the specific features of children with SJIA with RSI and their outcomes. Methods: In a single-center retrospective cohort study, we compared the information from the medical records of 200 children with SJIA according to ILAR criteria or SJIA-like disease (probable/possible SJIA) with and without signs of RSI (dyspnea, shortness of breath, pleurisy, acute respiratory distress syndrome, and interstitial lung disease (ILD)) at the disease onset and evaluated their outcomes (remission, development of chronic ILD, clubbing, and pulmonary arterial hypertension). Results: A quarter (25%) of the SJIA patients had signs of the RSI at onset and they more often had rash; hepato- and splenomegaly; heart (pericarditis, myocarditis), central nervous system, and kidney involvement; hemorrhagic syndrome; macrophage activation syndrome (MAS, 44.4% vs. 9.0%, p = 0.0000001); and, rarely, arthritis with fewer active joints, compared to patients without RSI. Five patients (10% from the group having RSI at the onset of SJIA and 2.5% from the whole SJIA cohort) developed fibrosing ILD. All of them had a severe relapsed/chronic course of MAS; 80% of them had a tocilizumab infusion reaction and further switched to canakinumab. Unfortunately, one patient with Down’s syndrome had gone. Conclusion: Patients with any signs of RSI at the onset of the SJIA are required to be closely monitored due to the high risk of the following fibrosing ILD development. They required prompt control of MAS, monitoring eosinophilia, and routine checks of night oxygen saturation for the prevention/early detection of chronic ILD. Full article

Background: Previous neuroimaging studies have identified brain regions related to respiratory motor control and perception. However, little is known about the resting-state functional connectivity (FC) associated with respiratory impairment. We aimed to determine the FC involved in mild respiratory impairment without altering transcutaneous oxygen saturation. Methods: We obtained resting-state functional magnetic resonance imaging data from 36 healthy volunteers during normal respiration and mild respiratory impairment induced by resistive load (effort breathing). ROI-to-ROI and seed-to-voxel analyses were performed using Statistical Parametric Mapping 12 and the CONN toolbox. Results: Compared to normal respiration, effort breathing activated FCs within and between the sensory perceptual area (postcentral gyrus, anterior insular cortex (AInsula), and anterior cingulate cortex) and visual cortex (the visual occipital, occipital pole (OP), and occipital fusiform gyrus). Graph theoretical analysis showed strong centrality in the visual cortex. A significant positive correlation was observed between the dyspnoea score (modified Borg scale) and FC between the left AInsula and right OP. Conclusions: These results suggested that the FCs within the respiratory sensory area via the network hub may be neural mechanisms underlying effort breathing and modified Borg scale scores. These findings may provide new insights into the visual networks that contribute to mild respiratory impairments. Full article

Aerosol delivery using conventional nebulizers with fixed maximal output rates is limited and unpredictable under high-flow conditions. This study measured regulated aerosol delivery to the lungs of normal volunteers using a nebulizer designed to overcome the limitations of HFNC therapy (i-AIRE (InspiRx, Inc., Somerset, NJ, USA)). This breath-enhanced jet nebulizer, in series with the high-flow catheter, utilizes the high flow to increase aerosol output beyond those of conventional devices. Nine normal subjects breathing tidally via the nose received humidified air at 60 L/min. The nebulizer was connected to the HFNC system upstream to the humidifier and received radio-labeled saline as a marker for drug delivery (^99mTc DTPA) infused by a syringe pump (mCi/min). The dose to the subject was regulated at 12, 20 and 50 mL/h. Rates of aerosol deposition in the lungs (µCi/min) were measured via a gamma camera for each infusion rate and converted to µg NaCl/min. The deposition rate, as expressed as µg of NaCl/min, was closely related to the infusion rate: 7.84 ± 3.2 at 12 mL/h, 43.0 ± 12 at 20 mL/h and 136 ± 45 at 50 mL/h. The deposition efficiency ranged from 0.44 to 1.82% of infused saline, with 6% deposited in the nose. A regional analysis indicated peripheral deposition of aerosol (central/peripheral ratio 0.99 ± 0.27). The data were independent of breathing frequency. Breath-enhanced nebulization via HFNC reliably delivered aerosol to the lungs at the highest nasal airflows. The rate of delivery was controlled simply by regulating the infusion rate, indicating that lung deposition in the critically ill can be titrated clinically at the bedside. Full article

Serotonin or 5-hydroxytryptamine (5-HT) is a ubiquitous neuro-modulator–transmitter that acts in the central nervous system, playing a major role in the control of breathing and other physiological functions. The midbrain, pons, and medulla regions contain several serotonergic nuclei with distinct physiological roles, including regulating the hypercapnic ventilatory response, upper airway patency, and sleep–wake states. Obesity is a major risk factor in the development of sleep-disordered breathing (SDB), such as obstructive sleep apnea (OSA), recurrent closure of the upper airway during sleep, and obesity hypoventilation syndrome (OHS), a condition characterized by daytime hypercapnia and hypoventilation during sleep. Approximately 936 million adults have OSA, and 32 million have OHS worldwide. 5-HT acts on 5-HT receptor subtypes that modulate neural control of breathing and upper airway patency. This article reviews the role of 5-HT in SDB and the current advances in 5-HT-targeted treatments for SDB. Full article