New epidemiologic evidence confirming that bias does not explain the aspirin/Reye's syndrome association

To determine the validity of the aspirin/Reye's syndrome association, we developed an epidemiologic investigation to assess the effects of five potential sources of bias. A case-control study incorporated procedures to avoid temporal precedence and susceptibility bias. These included classifying cases as having monophasic or biphasic patterns of illness and matching for severity of symptoms at zero-time. To evaluate the effect of a potential recall bias, an "alternate-condition" control group was enrolled. A medical record review study was conducted to assess the potential for diagnostic bias, and a blanket surveillance of all hospitals in a region was conducted to evaluate reporting bias. Twenty-four case subjects and 48 matched controls were enrolled. Eight-eight percent of case subjects and only 17% of controls had received aspirin prior to the onset of Reye's syndrome (matched odds ratio, 35; 95% confidence interval, 4.2 to 288). Further analyses demonstrated that the association could not be attributed to the five potential sources of bias.     

Synchrony levels during evoked seizure-like bursts in mouse neocortical slices

Slices (n = 45) from the somatosensory cortex of mouse (P8-13) generated spontaneous bursts of activity (0.10 +/- 0.05 Hz) that were recorded extracellularly. Multiunit action potential (AP) activity was integrated and used as an index of population activity. In this experimental model, seizure-like activity (SLA) was evoked with bicuculline (5-10 microM) or N-methyl-d-aspartate (NMDA, 5 microM). SLA was an episode with repetitive bursting at a frequency of 0.50 +/- 0.06 Hz. To evaluate whether SLA was associated with a change in synchrony, we obtained simultaneous intracellular and extracellular recordings (n = 40) and quantified the relationship between individual cells and the surrounding population of neurons. During the SLA there was an increase in population activity and bursting activity was observed in neurons and areas that were previously silent. We defined synchrony as cellular activity that is consistently locked with the population bursts. Signal-averaging techniques were used to determine this component. To quantitatively assess change in synchronous activity at SLA onset, we estimated the entropy of the single cell's spike trains and subdivided this measure into network burst-related information and noise-related entropy. The burst-related information was not significantly altered at the onset of NMDA-evoked SLA and slightly increased when evoked with bicuculline. The signal-to-noise ratio determined from the entropy estimates showed a significant decrease (instead of an expected increase) during SLA. We conclude that the increased population activity during the SLA is attributed to recruitment of neurons rather than to increased synchrony of each of the individual elements.     

Development and validation of a psychometric scale for assessing healthcare professionals' knowledge in radiation protection

Introduction

Healthcare professionals must sufficiently understand ionising radiation and the associated protection measures to avoid unnecessarily exposing patients and staff to ionising radiation. Hence, a proper safety culture is important to lowering health risks. The development and establishment of an instrument that can indicate healthcare professionals' understanding/knowledge of radiation protection concepts can greatly contribute to a good safety culture.The purpose of the present study was to develop and psychometrically test the Healthcare Professional Knowledge of Radiation Protection (HPKRP) self-evaluation scale, which was designed to measure the knowledge level of radiation protection by healthcare professionals working with ionising radiation in a clinical environment.

Balance and gait performance after maximal and submaximal endurance exercise in seniors: is there a higher fall-risk?

Impaired balance and gait performance increase fall-risk in seniors. Acute effects of different exercise bouts on gait and balance were not yet addressed. Therefore, 19 healthy seniors (10 women, 9 men, age: 64.6 ± 3.2 years) were examined on 3 days. After exhaustive treadmill testing, participants randomly completed a 2-km treadmill walking test (76 ± 8 % VO_2max) and a resting control condition. Standing balance performance (SBALP) was assessed by single limb-eyes opened (SLEO) and double limb-eyes closed (DLEC) stance. Gait parameters were collected at comfortable walking velocity. A condition × time interaction of center of pressure path length (COP_path) was observed for both balance tasks (p < 0.001). Small (Cohen’s d = 0.42, p = 0.05) and large (d = 1.04, p < 0.001) COP_path increases were found after 2-km and maximal exercise during DLEC. Regarding SLEO, slightly increased COP_path occurred after 2-km walking (d = 0.29, p = 0.65) and large increases after exhaustive exercise (d = 1.24, p < 0.001). No significant differences were found for gait parameters. Alterations of SBALP after exhaustive exercise might lead to higher fall-risk in seniors. Balance changes upon 2-km testing might be of minor relevance. Gait is not affected during single task walking at given velocities.     

A Community and Medical Library Collaboration to Address Senior Caregivers Barriers to Health Services Access

This describes an outreach program to improve access to community resources and online health information for the lay public and professionals engaged in caregiving to seniors. An academic health sciences library and a coalition of community organizations collaborated to develop an authoritative, web-enabled clearinghouse that consolidated access to regional and national health and social service resources and online health information. Findings from a mixed-methods approach of roundtable discussions, key informant structured interviews, and surveys of professionals involved in senior care planning and discharge management were used to develop, pilot test, and evaluate the project. The website was promoted through a series of webinars outlining the range of services and resources available as well as engagement with a variety of community health care organizations. This project advanced understanding of the needs of seniors and their caregivers and created mechanisms to improve access to authoritative health care information supporting senior care. Community feedback on the website launch highlights its value for the lay public and professional caregivers. It also provided a platform for volunteerism and service learning through which individuals can have a collective impact on their community.