The prevalence of SRBD in DMD is significant. There is a bimodal presentation of SRBD, with OSA found in the first decade and hypoventilation more commonly seen at the beginning of the second decade. Polysomnography is recommended in children with symptoms of OSA, or at the stage of becoming wheelchair-bound. In patients with the early stages of respiratory failure, assessment with polysomnography-identified sleep hypoventilation and assisted in initiating NIV.

f Specific major histocompatibility complex (MHC) class I alleles are associated with an increased frequency of spontaneous control of human and simian immunodeficiency viruses (HIV and SIV). The mechanism of control is thought to involve MHC class I-restricted CD8 ؉ T cells, but it is not clear whether particular CD8 ؉ T cell responses or a broad repertoire of epitope-specific CD8 ؉ T cell populations (termed T cell breadth) are principally responsible for mediating immunologic control. To test the hypothesis that heterozygous macaques control SIV replication as a function of superior T cell breadth, we infected MHC-homozygous and MHC-heterozygous cynomolgus macaques with the pathogenic virus SIVmac239. As measured by a gamma interferon enzyme-linked immunosorbent spot assay (IFN-␥ ELISPOT) using blood, T cell breadth did not differ significantly between homozygotes and heterozygotes. Surprisingly, macaques that controlled SIV replication, regardless of their MHC zygosity, shared durable T cell responses against similar regions of Nef. While the limited genetic variability in these animals prevents us from making generalizations about the importance of Nef-specific T cell responses in controlling HIV, these results suggest that the T cell-mediated control of virus replication that we observed is more likely the consequence of targeting specificity rather than T cell breadth.

Red Bull energy drink has become extraordinarily popular amongst college students for use as a study aid. We investigated the combined effects of Red Bull's two active ingredients, caffeine and taurine, on short term memory. Studies on the effects of these two neuromodulators on memory have yielded mixed results, and their combined actions have not yet been investigated. In this double-blind study, college student subjects consumed either caffeine and taurine pills or a placebo and then completed a memory assessment. Heart rate and blood pressure were monitored throughout the testing period. The combination of caffeine and taurine had no effect on short term memory, but did cause a significant decline in heart rate and an increase in mean arterial blood pressure. The heart rate decline may have been caused by pressure-induced bradycardia that was triggered by caffeine ingestion and perhaps enhanced by the actions of taurine.

OBJECTIVES: It remains uncertain whether treatment with adenotonsillectomy for obstructive sleep apnea in children improves cognitive function. The Preschool Obstructive Sleep Apnea Tonsillectomy and Adenoidectomy study was a prospective randomized controlled study in which researchers evaluated outcomes 12 months after adenotonsillectomy compared with no surgery in preschool children symptomatic for obstructive sleep apnea.METHODS: A total of 190 children (age 3-5 years) were randomly assigned to early adenotonsillectomy (within 2 months) or to routine wait lists (12-month wait, no adenotonsillectomy [NoAT]). Baseline and 12-month assessments included cognitive and behavioral testing, medical assessment, polysomnography, and audiology. The primary outcome was global IQ at 12-month follow-up, measured by the Woodcock Johnson III Brief Intellectual Ability (BIA). Questionnaires included the Pediatric Sleep Questionnaire, Parent Rating Scale of the Behavioral Assessment System for Children-II, and Behavior Rating Inventory of Executive Function, Preschool Version.RESULTS: A total of 141 children (75.8%) attended baseline and 12-month assessments, and BIA was obtained at baseline and 12-month follow-up for 61 and 60 participants in the adenotonsillectomy versus NoAT groups, respectively. No cognitive gain was found after adenotonsillectomy compared with NoAT, adjusted for baseline; BIA scores at 12-month follow-up were as follows: adenotonsillectomy, 465.46 (17.9) versus NoAT, 463.12 (16.6) (mean [SD]). Improvements were seen for polysomnogram arousals and apnea indices and for parent reports of symptoms (Pediatric Sleep Questionnaire), behavior (Behavior Assessment System for Children behavioral symptoms, P = .04), overall health, and daytime napping. CONCLUSIONS: Structured testing showed no treatment-attributable improvement in cognitive functioning of preschool children 12 months after adenotonsillectomy compared with NoAT. Improvements were seen after adenotonsillectomy in sleep and behavior by using polysomnogram monitoring and parental questionnaires.WHAT'S KNOWN ON THIS SUBJECT: Studies to evaluate changes in neurocognition after adenotonsillectomy for obstructive sleep apnea suggest that younger children may have potential for greater improvement. The previous study with a randomized design was in school-aged children.WHAT THIS STUDY ADDS: This randomized study of preschool children showed reduced frequency of day naps and confirmed polysomnographic and behavioral improvements after adenotonsillectomy compared with those still awaiting surgery, but our primary analysis showed no improvement in global IQ.

The overall CD8 T cell response to human/simian immunodeficiency virus (HIV/SIV) targets a collection of discrete epitope specificities. Some of these epitope-specific CD8 T cells emerge in the weeks and months following infection and rapidly select for sequence variants, whereas other CD8 T cell responses develop during the chronic infection phase and rarely select for sequence variants. In this study, we tested the hypothesis that acute-phase CD8 T cell responses that do not rapidly select for escape variants are unable to control viral replication in vivo as well as those that do rapidly select for escape variants. We created a derivative of live attenuated SIV (SIVmac239Δnef) in which we ablated five epitopes that elicit early CD8 T cell responses and rapidly accumulate sequence variants in SIVmac239-infected Mauritian cynomolgus macaques (MCMs) that are homozygous for the M3 major histocompatibility complex (MHC) haplotype. This live attenuated SIV variant was called m3KOΔnef. Viremia was significantly higher in M3 homozygous MCMs infected with m3KOΔnef than in either MHC-mismatched MCMs infected with m3KOΔnef or MCMs infected with SIVmac239Δnef. Three CD8 T cell responses, including two that do not rapidly select for escape variants, predominated during early m3KOΔnef infection in the M3 homozygous MCMs, but these animals were unable to control viral replication. These results provide evidence that acute-phase CD8 T cell responses that have the potential to rapidly select for escape variants in the early phase of infection are needed to establish viral control in vivo.