Developmental changes in upper airway dynamics

Normal children have a less collapsible upper airway in response to subatmospheric pressure administration (P-NEG) during steep than normal adults do, and this upper airway response appears to be modulated by the central ventilatory drive. Children have a greater ventilatory drive than adults. We, therefore, hypothesized that children have increased neuromotor activation of their pharyngeal airway during sleep compared with adults. As infants have few obstructive apneas during steep, we hypothesized that infants would have an upper airway that was resistant to collapse. We, therefore, compared the upper airway pressure-flow (V) relationship during sleep between normal infants, prepubertal children, and adults. We evaluated the upper airway response to 1) intermittent, acute P-NEG (infants, children, and adults), and 2) hypercapnia (children and adults). We found that adults had a more collapsible upper airway during sleep than either infants or children. the children exhibited a vigorous response to both P-NEG and hypercapnia during sleep (P < 0.01), whereas adults had no significant change. Infants had an airway that was resistant to collapse and showed a very rapid response to P-NEG. We conclude that the upper airway is resistant to collapse during sleep in infants and children. Normal children have preservation of upper airway responses to P-NEG and hypercapnia during sleep, whereas responses are diminished in adults. Infants appear to have a different pattern of upper airway activation than older children. We speculate that the pharyngeal airway responses present in normal children are a compensatory response for a relatively narrow upper airway.Johns Hopkins Univ, Eudowood Div Pediat Resp Sci, Baltimore, MD 21287 USAJohns Hopkins Univ, Div Oncol Biostat, Baltimore, MD 21287 USAUniversidade Federal de São Paulo, Escola Paulista Med, Dept Neurol & Internal Med, São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Neurol & Internal Med, São Paulo, BrazilWeb of Scienc

Genomic imbalances in esophageal squamous cell carcinoma identified by molecular cytogenetic techniques

This review summarizes the chromosomal changes detected by molecular cytogenetic approaches in esophageal squamous cell carcinoma (ESCC), the ninth most common malignancy in the world. Whole genome analyses of ESCC cell lines and tumors indicated that the most frequent genomic gains occurred at 1, 2q, 3q, 5p, 6p, 7, 8q, 9q, 11q, 12p, 14q, 15q, 16, 17, 18p, 19q, 20q, 22q and X, with focal amplifications at 1q32, 2p16-22, 3q25-28, 5p13-15.3, 7p12-22, 7q21-22, 8q23-24.2, 9q34, 10q21, 11p11.2, 11q13, 13q32, 14q13-14, 14q21, 14q31-32, 15q22-26, 17p11.2, 18p11.2-11.3 and 20p11.2. Recurrent losses involved 3p, 4, 5q, 6q, 7q, 8p, 9, 10p, 12p, 13, 14p, 15p, 18, 19p, 20, 22, Xp and Y. Gains at 5p and 7q, and deletions at 4p, 9p, and 11q were significant prognostic factors for patients with ESCC. Gains at 6p and 20p, and losses at 10p and 10q were the most significant imbalances, both in primary carcinoma and in metastases, which suggested that these regions may harbor oncogenes and tumor suppressor genes. Gains at 12p and losses at 3p may be associated with poor relapse-free survival. The clinical applicability of these changes as markers for the diagnosis and prognosis of ESCC, or as molecular targets for personalized therapy should be evaluated

Body position and obstructive sleep apnea in children

Study Objectives: In adults, sleep apnea is worse when the patient is in the supine position. However, the relationship between sleep position and obstructive apnea in children is unknown. The objective of this study was to evaluate the relationship between obstructive apnea and body position during sleep in children.Design: Retrospective analysis of the relationship between body position and obstructive apnea in obese and non-obese children.Setting: Tertiary care pediatric sleep center.Patients: Otherwise healthy children, aged 1-10 years, undergoing polysomnography for suspected obstructive sleep apnea syndrome. Obese and non-obese children were evaluated separately.Interventions: Retrospective review of the relationship between sleep position and obstructive apnea during polysomnography.Measurements and Results: Eighty polysomnograms from 56 non-obese and 24 obese children were analyzed. Body position was determined by a sensor during polysomnography, and confirmed by review of videotapes. Children had a lower obstructive apnea hypopnea index when supine vs. prone, and shorter apneas when supine then when on their side. There was no difference in apnea duration between the supine and prone positions. Obese and non-obese children showed similar positional changes.Conclusions: Children with obstructive sleep apnea, in contrast to adults, breathe best when in the supine position.Univ Fed Sao Paulo, Escola Paulista Med, Dept Neurol & Internal Med, Sao Paulo, BrazilJohns Hopkins Univ, Johns Hopkins Biostat Ctr, Baltimore, MD USAJohns Hopkins Univ, Eudowood Div Pediat Resp Sci, Baltimore, MD USAUniv Fed Sao Paulo, Escola Paulista Med, Dept Neurol & Internal Med, Sao Paulo, BrazilWeb of Scienc

Cognitive dysfunction in children with sleep-disordered breathing

Two daily school periods are mandatory in Brazil owing to a shortage of academic facilities, which can decrease cognitive performance, especially in children with sleep-disordered breathing. This study aimed to verify the influence of starting time to school on cognition, comparing children with sleep disorders and normal children. Cognition was assessed in 79 children with sleep-disordered breathing, 468 children with nonrespiratory sleep disorders, and 633 normal control children. We analyzed total sleep time, starting time to school (morning or afternoon), and grades. First grade morning students with sleep-disordered breathing had 8.04 higher odds for cognitive dysfunction than normal children. For children with sleep-disordered breathing, second and third grade morning students had higher odds for cognitive dysfunction than those who studied in the afternoon (3.69 and 4.07). Fourth grade morning students had 8.27 higher odds for cognitive dysfunction than first grade children. In conclusion, sleep-disordered breathing, grades, and starting time to school interact to affect cognition in Brazilian children.Univ Fed Sao Paulo, Dept Neurol, Sleep Disorder Ctr, Sao Paulo, BrazilUniv Fed Sao Paulo, Dept Emergency Med, Sao Paulo, BrazilUniv Fed Sao Paulo, Dept Neurol, Sleep Disorder Ctr, Sao Paulo, BrazilUniv Fed Sao Paulo, Dept Emergency Med, Sao Paulo, BrazilWeb of Scienc

Alterations of the CCND1 and HER-2/neu (ERBB2) proteins in esophageal and gastric cancers

We evaluated the relationship of amplification and polysomy of both the CCND1 and the ERBB2 (alias HER-2/NEU) genes to the overexpression of their proteins in esophageal and gastric cancers and also their association with clinicopathological features. CCND1 gene amplification (45%) was more prevalent than polysomy (25%) in esophageal carcinoma, but the pattern observed was similar in gastric adenocarcinoma (10% amplification, 15% polysomy). For ERBB2, polysomy was a more frequent mechanism than amplification in both esophageal (32.5 vs. 7.5%) and gastric (15 vs. 5%) cancers. Overexpression of cyclin D1 protein was identified in 37.5% of the specimens of esophageal tumors and 35% of gastric tumors, and overexpression of Her-2/neu protein in 12.5 and 7.5%, respectively. The K-statistics revealed a fair agreement in both types of turners only in overexpression and amplification of the CCND1 ggene; the ERBB2 gene showed a fair agreement in amplification and polysomy and the level of protein expression in gastric adenocarcinorna. Thus, polysomy 17 could contribute to a high Her-2/neu protein level, at least in gastric cancer. Our data indicated an association with alcohol consumption and the CCND1 gene or protein levels, in both esophageal and gastric cancers. (c) 2006 Elsevier B.V. All rights reserved