Glucocorticoid receptor subunit expression in adenotonsillar tissue of children with obstructive sleep apnea.

Tonsillectomy and adenoidectomy (T&A) is a frequent surgical procedure in children with obstructive sleep apnea (OSA). Many symptomatic children who do not fulfill the currently recommended criteria for T&A may benefit from topical intranasal steroid therapy. However, the expression of glucocorticoid receptor (GCR) expression in adenoid and tonsillar tissue is currently unknown.

Mild sustained and intermittent hypoxia induce apoptosis in PC-12 cells via different mechanisms.

Episodic hypoxia, a characteristic feature of obstructive sleep apnea, induces cellular changes and apoptosis in brain regions associated with neurocognitive function. To investigate whether mild, intermittent hypoxia would induce more extensive neuronal damage than would a similar degree of sustained hypoxia, rat pheochromocytoma PC-12 neuronal cells were subjected to either sustained (5% O(2)) or intermittent (alternating 5% O(2) 35 min, 21% O(2) 25 min) hypoxia for 2 or 4 days. Quantitative assessment of apoptosis showed that while mild sustained hypoxia did not significantly increase cell apoptosis at 2 days (1.

Health-related quality of life and depressive symptoms in children with suspected sleep-disordered breathing.

Study Objectives: Snoring and sleep-disordered breathing (SDB) are highly prevalent among children. The increasing trends of obesity in the pediatric population further predict an exacerbation of this public health problem. However, the impact of SDB on mood and quality of life and the confounder effect of obesity in this setting are unclear.

Increased production of reactive oxygen species contributes to motor neuron death in a compression mouse model of spinal cord injury.

Study Design: Experimental laboratory investigation of the role and pathways of reactive oxygen species (ROS)-mediated motor neuron cell death in a mouse model of compression spinal cord injury.

Objectives: To analyze ROS-mediated oxidative stress propagation and signal transduction leading to motor neuron apoptosis induced by compression spinal cord injury.

Setting: University of Louisville Health Science Center.

Enhanced rat beta-cell proliferation in 60% pancreatectomized islets by increased glucose metabolic flux through pyruvate carboxylase pathway.

Islet beta-cell proliferation is a very important component of beta-cell adaptation to insulin resistance and prevention of type 2 diabetes mellitus. However, we know little about the mechanisms of beta-cell proliferation. We now investigate the relationship between pyruvate carboxylase (PC) pathway activity and islet cell proliferation 5 days after 60% pancreatectomy (Px).

Nitric oxide synthase and intermittent hypoxia-induced spatial learning deficits in the rat.

Intermittent hypoxia (IH) during sleep induces significant neurobehavioral deficits in the rat. Since nitric oxide (NO) has been implicated in ischemia-reperfusion-related pathophysiological consequences, the temporal effects of IH (alternating 21% and 10% O(2) every 90 s) and sustained hypoxia (SH; 10% O(2)) during sleep for up to 14 days on the induction of nitric oxide synthase (NOS) isoforms in the brain were examined in the cortex of Sprague-Dawley rats. No significant changes of endothelial NOS (eNOS) and neuronal NOS (nNOS) occurred over time with either IH or SH.

Non-iatrogenic pathology of the preterm infant.

Non-iatrogenic anatomical findings at autopsy provide insight into preterm infant physiology. The different patterns of lipid accumulation in the adrenal may correspond to long-term differences in stress response. Cardiac papillary muscle infarction occurs with asphyxia or shock and can explain myocardial dysfunction.

Differential expression of cysteinyl leukotriene receptors 1 and 2 in tonsils of children with obstructive sleep apnea syndrome or recurrent infection.

Background: Recurrent tonsillitis and sleep apnea are the major indications for tonsillectomy in children. We hypothesized that the recurrent vibration in the upper airway of snoring children would promote inflammatory changes in the tonsillar tissue and would lead to the up-regulation of cysteinyl leukotriene (LT) receptors (Rs).

Objective: To assess the expression patterns of the human LT-Rs in children undergoing tonsillectomy, and compare those patterns in children having recurrent throat infections (RIs) and children with obstructive sleep apnea syndrome (SA).

Platelet-activating factor receptor and respiratory and metabolic responses to hypoxia and hypercapnia.

Activation of the platelet-activating factor receptor (PAFR) regulates neural transmission. A PAFR blocker reduced the peak hypoxic (pHVR) but not hypercapnic ventilatory (HCVR) responses in rats [Am. J.

Neurobehavioral implications of habitual snoring in children.

Objective: Current guidelines for the treatment of children with obstructive sleep apnea (OSA) suggest that primary snoring (PS) in children is benign. However, PS has not been well evaluated, and it is unknown whether PS is associated with serious morbidity. This study investigated whether PS is associated with neurobehavioral deficits in children.

Increased oxidative stress is associated with chronic intermittent hypoxia-mediated brain cortical neuronal cell apoptosis in a mouse model of sleep apnea.

Chronic intermittent hypoxia (CIH), as occurs in obstructive sleep apnea (SA), is associated with substantial cortico-hippocampal damage leading to impairments of neurocognitive, respiratory and cardiovascular functions. Previous studies in a rat model have shown that CIH increases brain cortical neuronal cell death. However, the molecular events leading to CIH-mediated neuronal cell death remain largely undefined.

The role of complement in neonatal hypoxic-ischemic cerebral injury.

Complement activation participates in tissue injury after temporary loss of blood flow (ischemia-reperfusion injury). Recently reported evidence indicates that complement activation is a pathologic mechanism of injury in the post-hypoxic-ischemic neonatal brain. Therefore, recently developed complement inhibitors may find a role in the amelioration of neonatal hypoxic-ischemic cerebral injury.

Neurobehavioral correlates of sleep-disordered breathing in children.

The effects of sleep-disordered breathing (SDB) on neurobehavioral function were examined in two matched groups of children from the general population. Thirty-five children with polysomnographically confirmed SDB were matched for ethnicity, age, gender, maternal educational attainment, and maternal smoking, to healthy children with no evidence of SDB. Children with SDB had significantly lower mean scores on the Differential Ability Scales for General Conceptual Ability (similar to IQ) and for the Non-verbal Cluster.

Plasma C-reactive protein levels among children with sleep-disordered breathing.

Introduction: Levels of C-reactive protein (CRP), an important serum marker of inflammation with major implications for cardiovascular morbidity and atherogenesis, are elevated among adult patients with sleep-disordered breathing (SDB). We hypothesized that elevated CRP plasma levels would also be present among children with SDB.

Methods: Eighty-one children (mean age: 9.

New concepts in abnormalities of respiratory control in children.

Purpose Of Review: Respiratory control disorders such as apnea of prematurity, apparent life-threatening events, sudden infant death syndrome, and central hypoventilation are relatively frequent conditions in the pediatric age range and are associated with substantial morbidity and mortality. The explosion of technological breakthroughs in biology and medicine has facilitated our understanding of the fundamental mechanisms that govern the development of brain regions underlying respiratory control functions.

Recent Findings: Recent critically important discoveries encompass the identification of neurons that constitute the central respiratory rhythm generator in the brainstem, the conceptual framework allowing for many neurons located in multiple strategic regions within the brain to coordinate central chemosensitivity, the discovery of long-term and short-term plasticity in hypoxic ventilatory regulation, and the recent uncovering of specific gene mutations in children affected with congenital central hypoventilation syndrome.

Psychiatric symptoms in children with insomnia referred to a pediatric sleep medicine center.

Background And Purpose: To assess the frequency and nature of clinical and psychiatric symptoms in children referred to a pediatric sleep center for evaluation of insomnia.

Patients And Methods: A retrospective chart review of all children referred to the pediatric sleep medicine was conducted. Children presenting exclusively with sleep initiation and/or maintenance problems underwent a structured clinical psychiatric interview and their parents completed the behavioral assessment system for children (BASC), pediatric symptom checklist, the clinical attention problem scale and a detailed sleep questionnaire.

Peripheral arterial tonometry events and electroencephalographic arousals in children.

Study Objectives: Peripheral arterial tonometry (PAT) is a sensitive measure of moment-to-moment changes in sympathetic activity and reliably identifies arousals in adult subjects. We investigated whether PAT events during sleep are associated with visually recognizable electroencephalographic arousals in healthy children and in children with sleep-disordered breathing.

Design: Prospective cohort.

Sleep pressure correlates of cognitive and behavioral morbidity in snoring children.

Study Objectives: Sleep architecture is not preserved in children with sleep-disordered breathing but, rather, undergoes dynamic changes that exhibit significant correlation with severity of sleep-disordered breathing. A sleep pressure score (SPS) with a cutoff value of 0.25 was derived from analysis of a large cohort of snoring and control children.

Sleep pressure score: a new index of sleep disruption in snoring children.

Study Objectives: Excessive daytime sleepiness (EDS), as measured by objective criteria, is infrequent in snoring children despite a high prevalence of EDS-related behavioral manifestations. We hypothesized that sleep architecture and arousal indexes may be altered relative to the severity of sleep-disordered breathing (SDB).

Design: Retrospective and prospective study.

Platelet-activating factor receptor modulates respiratory adaptation to long-term intermittent hypoxia in mice.

During hypoxia, release of platelet-activating factor (PAF) and activation of its cognate receptor (PAFR) regulate neural transmission and are required for full expression of peak hypoxic ventilatory response (pHVR) but not hypercapnic ventilatory response. However, it is unclear whether PAFR underlie components of long-term ventilatory adaptations to hypoxia. To examine this issue, adult male PAFR(+/+) and PAFR(-/-) mice were exposed to intermittent hypoxia (IH) consisting of 90 s 21% O(2) and 90 s 10% O(2) for 30 days, and normoxic and hypoxic ventilatory patterns were assessed using whole body plethysmography.

Platelet-activating factor receptor-deficient mice are protected from experimental sleep apnea-induced learning deficits.

Intermittent hypoxia (IH) during sleep, a hallmark of sleep apnea, is associated with neurobehavioral impairments, regional neurodegeneration and increased oxidative stress and inflammation in rodents. Platelet-activating factor (PAF) is an important mediator of both normal neural plasticity and brain injury. We report that mice deficient in the cell surface receptor for PAF (PAFR-/-), a bioactive mediator of oxidative stress and inflammation, are protected from the spatial reference learning deficits associated with IH.