Background: Sympathetic nervous system hyperactivity and chronic intermittent nocturnal hypoxia in individuals with obstructive sleep apnea (OSA) predispose them to microvascular impairment, which may contribute to increased daytime muscle fatigue. This study aimed to assess microvascular reactivity of the skeletal muscle, examine fatigability, and determine the relationship between fatigability and microvascular reactivity in adults with OSA.
Methods: Twenty-six participants were allocated into two groups-those with OSA and those without i.
Mild intermittent hypoxia initiates progressive augmentation (PA) and ventilatory long-term facilitation (vLTF) in humans. The magnitude of these forms of plasticity might be influenced by anthropometric and physiological variables, as well as protocol elements. However, the impact of many of these variables on the magnitude of respiratory plasticity has not been established in humans.
View Article and Find Full Text PDFStudy Objectives: Previous studies reported that the apnea-hypopnea index was similar in young adult Black and White participants. However, whether this similarity reflects an analogous combination of apneas and hypopneas is unknown. Likewise, the physiological mechanisms underlying this similarity has not been explored.
View Article and Find Full Text PDFResting minute ventilation and ventilation during and following hypoxia may be enhanced following daily exposure to mild intermittent hypoxia (MIH). In contrast, resting systolic blood pressure (SBP) is reduced following daily exposure to MIH. However, it is presently unknown if the reduction in resting SBP following daily exposure, is coupled with reduced SBP responses during and after acute exposure to MIH.
View Article and Find Full Text PDFDaily exposure to mild intermittent hypoxia (MIH) may elicit beneficial cardiovascular outcomes. To determine the effect of 15 days of MIH and in-home continuous positive airway pressure treatment on blood pressure in participants with obstructive sleep apnea and hypertension. We administered MIH during wakefulness 5 days/week for 3 weeks.
View Article and Find Full Text PDFThis review explores forms of respiratory and autonomic plasticity, and associated outcome measures, that are initiated by exposure to intermittent hypoxia. The review focuses primarily on studies that have been completed in humans and primarily explores the impact of mild intermittent hypoxia on outcome measures. Studies that have explored two forms of respiratory plasticity, progressive augmentation of the hypoxic ventilatory response and long-term facilitation of ventilation and upper airway muscle activity, are initially reviewed.
View Article and Find Full Text PDFWe investigated whether time of day affects loop gain (LG) and the arousal threshold (AT) during non-rapid eye movement (NREM) sleep. Eleven men with obstructive sleep apnea (apnea-hypopnea index > 5 events/h) completed a constant-routine protocol that comprised 3-h sleep sessions in the evening [10 PM (1) to 1 AM], morning (6 AM to 9 AM), afternoon (2 PM to 5 PM), and subsequent evening [10 PM (2) to 1 AM]. During each sleep session LG and the AT were measured during NREM sleep with a model-based approach.
View Article and Find Full Text PDFLung cancer has second highest rate of incidence and mortality around the world. Smoking cigarettes is the main stream cause of lung carcinogenesis along with other factors such as spontaneous mutations, inactivation of tumor suppressor genes. The present study was aimed to identify the mechanistic role of Imatinib in the chemoprevention of experimental lung carcinogenesis in rat model.
View Article and Find Full Text PDFSleep disturbance is a common symptom in institutionalized older adults that reduces their quality of life and may contribute to progression of cognitive impairment. While we found that a 7-week combination of resistance training, walking and social activity significantly improved sleep in institutionalized older adults compared with a usual care control group, no one to our knowledge has determined the acute effects of resistance training on same-day sleep in this population. Given the effort required to promote exercise adherence in institutionalized older adults and to obtain a positive training effect, understanding of the acute effects of resistance training on same-day sleep architecture should be elucidated, especially with respect to unintended consequences.
View Article and Find Full Text PDFObjectives: To determine the effect of 7 weeks of resistance training and walking on the apnea-hypopnea index (AHI) in institutionalized older adults compared with a usual care control group.
Design: Secondary analysis of data from a randomized controlled trial.
Setting: Ten nursing and 3 assisted living facilities in Arkansas.
Purpose: To evaluate the functional capacity following mitral valve replacement in the early postoperative period and to determine the correlation of biventricular function and residual pulmonary artery hypertension (PAH) to the functional capacity.
Methods: On the seventh postoperative day, 53 patients who underwent mitral valve replacement with preoperative diagnosis of PAH underwent a 2-dimensional echocardiographic and Doppler examination for the assessment of right ventricular systolic pressure, along with right ventricular (RV) and left ventricular (LV) myocardial performance indices (MPIs). These assessments were followed by a 6-Minute Walk Test.