A P EDIATRIC S URVEY FOR THE N ATIONAL H IGHWAY T RAFFIC S AFETY A DMINISTRATION : E MERGENCY M EDICAL S ERVICES S YSTEM R E-ASSESSMENTS

Emergency medical services for children, or EMSC, is still a relatively underdeveloped component of most state and local EMS systems. Advocacy and funding for EMSC from the federal EMSC Program, availability of many useful EMSC products, and the rapidly enlarging literature in EMSC have created heightened awareness and interest in improving systems for pediatric emergency, trauma, and critical care. The new National Highway Traffic Safety Administration (NHTSA) EMS Technical Assistance (TA) re-assessment program, the second version of the successful original TA Program from 1988 to 1996, provides an ideal opportunity for state EMS professionals to evaluate EMSC capabilities and to integrate new EMSC products and services. The history of the TA Program reflects the evolution of EMS itself and indicates a historical inattention to children's issues, but re-assessment TA teams now have much useful intervening EMSC history to draw upon and a clear philosophical mandate to integrate children more fully in EMS system planning and management. In order to facilitate state-of-the-art reviews of EMSC within state EMS systems, a pediatric survey for the NHTSA re-assessments is presented. The survey, developed with the input of EMS administrators and physicians and approved by the National Association of State EMS Directors, follows the original ten-component model for EMS system review. It is intended for optional use within the overall EMS review process.     

Teaching advanced operation of an iPod-based speech-generating device to two students with autism spectrum disorders

We evaluated a program for teaching two adolescents with autism spectrum disorders (ASD) to perform more advanced operations on an iPod-based speech-generating device (SGD). The effects of the teaching program were evaluated in a multiprobe multiple baseline across participants design that included two intervention phases. The first intervention focused on teaching the students to navigate between two screen pages and complete a multi-step response sequence to request preferred stimuli. The second intervention aimed to teach the students to turn on and unlock the device prior to navigating to the correct screen pages. Teaching procedures included response prompting, prompt fading, and differential reinforcement. Results showed that both interventions were effective in teaching the respective operations. Learning advanced operation of the iPod-based SGD could be seen as one way to promote greater independence in using such devices for multi-step communication.     

MicroRNAs in nasopharyngeal carcinoma

MicroRNAs（miRNAs） provide insight into both the biology and clinical behavior of many human cancers, including nasopharyngeal carcinoma（NPC）. The dysregulation of miRNAs in NPC results in a variety of tumor-promoting effects. Furthermore, several miRNAs are prognostic markers for NPC. In addition to cellular miRNAs, NPC samples also often contain miRNAs encoded by Epstein-Barr virus, and these miRNAs may impact NPC biology by targeting both cellular and viral genes. Given their numerous putative roles in NPC development and progression, a thorough understanding of the impact of miRNA dysregulation in NPC is expected to shed light on useful biomarkers and therapeutic targets for the clinical management of this disease. In this review, we describe the efforts to date to identify and characterize such miRNAs in the context of NPC.     

Single-dose vaccine against tick-borne encephalitis

Tick-borne encephalitis (TBE) virus is the most important human pathogen transmitted by ticks in Eurasia. Inactivated vaccines are available but require multiple doses and frequent boosters to induce and maintain immunity. Thus far, the goal of developing a safe, live attenuated vaccine effective after a single dose has remained elusive. Here we used a replication-defective (single-cycle) flavivirus platform, RepliVax, to generate a safe, single-dose TBE vaccine. Several RepliVax-TBE candidates attenuated by a deletion in the capsid gene were constructed using different flavivirus backbones containing the envelope genes of TBE virus. RepliVax-TBE based on a West Nile virus backbone (RV-WN/TBE) grew more efficiently in helper cells than candidates based on Langat E5, TBE, and yellow fever 17D backbones, and was found to be highly immunogenic and efficacious in mice. Live chimeric yellow fever 17D/TBE, Dengue 2/TBE, and Langat E5/TBE candidates were also constructed but were found to be underattenuated. RV-WN/TBE was demonstrated to be highly immunogenic in Rhesus macaques after a single dose, inducing a significantly more durable humoral immune response compared with three doses of a licensed, adjuvanted human inactivated vaccine. Its immunogenicity was not significantly affected by preexisting immunity against WN. Immunized monkeys were protected from a stringent surrogate challenge. These results support the identification of a single-cycle TBE vaccine with a superior product profile to existing inactivated vaccines, which could lead to improved vaccine coverage and control of the disease.     

Nonexponential T2* decay in white matter

Visualizing myelin in human brain may help the study of diseases such as multiple sclerosis. Previous studies based on T₁ and T₂ relaxation contrast have suggested the presence of a distinct water pool that may report directly on local myelin content. Recent work indicates that T₂* contrast may offer particular advantages over T₁ and T₂ contrast, especially at high field. However, the complex mechanism underlying T₂* relaxation may render interpretation difficult. To address this issue, T₂* relaxation behavior in human brain was studied at 3 and 7 T. Multiple gradient echoes covering most of the decay curve were analyzed for deviations from mono‐exponential behavior. The data confirm the previous finding of a distinct rapidly relaxing signal component (T₂* ～ 6 ms), tentatively attributed to myelin water. However, in extension to previous findings, this rapidly relaxing component displayed a substantial resonance frequency shift, reaching 36 Hz in the corpus callosum at 7 T. The component's fractional amplitude and frequency shift appeared to depend on both field strength and fiber orientation, consistent with a mechanism originating from magnetic susceptibility effects. The findings suggest that T₂* contrast at high field may be uniquely sensitive to tissue myelin content and that proper interpretation will require modeling of susceptibility‐induced resonance frequency shifts. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.