An evaluation of the reliability of the foot-tapping test in a healthy sample

The foot-tapping test (FTT) can be used to assess upper motor neuron dysfunction in clinical populations. However, relatively little is known regarding the reliability or normative values of the FTT in either healthy or clinical populations. Although several different FTT methods have been used, no study to date has demonstrated the reliability or validity of FTT by comparing it across several different counting methods in healthy persons. This unfortunately limits its usefulness in medicine and research.Open Access fees paid for in whole or in part by the University of Oklahoma Libraries.Ye

Group B Streptococcal β-Hemolysin/Cytolysin Directly Impairs Cardiomyocyte Viability and Function

BACKGROUND: Group B Streptococcus (GBS) is a leading cause of neonatal sepsis where myocardial dysfunction is an important contributor to poor outcome. Here we study the effects of the GBS pore-forming beta-hemolysin/cytolysin (Bh/c) exotoxin on cardiomyocyte viability, contractility, and calcium transients. METHODOLOGY/PRINCIPAL FINDINGS: HL-1 cardiomyocytes exposed to intact wild-type (WT) or isogenic Deltabeta h/c mutant GBS, or to cell-free extracts from either strain, were assessed for viability by trypan blue exclusion and for apoptosis by TUNEL staining. Functionality of exposed cardiomyocytes was analyzed by visual quantitation of the rate and extent of contractility. Mitochondrial membrane polarization was measured in TMRE-loaded cells exposed to GBS beta h/c. Effects of GBS beta h/c on calcium transients were studied in fura-2AM-loaded primary rat ventricular cardiomyocytes. Exposure of HL-1 cardiomyocytes to either WT GBS or beta h/c extracts significantly reduced both rate and extent of contractility and later induced necrotic and apoptotic cell death. No effects on cardiomyocyte viability or function were observed after treatment with Deltabeta h/c mutant bacteria or extracts. The beta h/c toxin was associated with complete and rapid loss of detectable calcium transients in primary neonatal rat ventricular cardiomyocytes and induced a loss of mitochondrial membrane polarization. These effects on viability and function were abrogated by the beta h/c inhibitor, dipalmitoyl phosphatidylcholine (DPPC). CONCLUSIONS/SIGNIFICANCE: Our data show a rapid loss of cardiomyocyte viability and function induced by GBS beta h/c, and these deleterious effects are inhibited by DPPC, a normal constituent of human pulmonary surfactant.. These findings have clinical implications for the cardiac dysfunction observed in neonatal GBS infections

Parental perceptions regarding mandatory mouthguard use in competitive youth soccer

Objective: To understand factors that influence parental perceptions regarding mandatory mouthguard use in competitive youth soccer. Setting and subjects: A web based survey of parents whose 8–14 year old children participated in outdoor competitive youth soccer during the fall of 2002. Questions focused on: previous injury, education provided, dentist/physician recommendations, and parental perceptions of mouthguard use. Main outcome measure: The outcome variable was parental agreement with the statement "mouthguards should be mandatory for competitive youth soccer". Logistic regression and χ(2) were performed using STATA 8.0. Results: Altogether 120 parents participated. The children had a mean (SD) age of 11.8 (1.5) years and 48% were female; 14% wore mouthguards and 11% suffered orofacial injuries. Nineteen percent of parents reported receiving educational material from the youth soccer organization. Although 92% of parents believed that mouthguards were effective in reducing orofacial injuries, only one half agreed that mouthguards should be mandatory. Thirty percent of respondents reported that their dentist/physician recommended mouthguards for competitive youth soccer. Logistic regression showed that dentist/physician recommendation and parental female gender were independently associated with parental agreement for mandatory mouthguard use (odds ratio 2.9, 95% confidence interval (CI) 1.2 to 7.3; odds ratio 3.0, 95% CI 1.1 to 6.5). Conclusions: Few athletes wear mouthguards during competitive youth soccer. Health care professionals in this study did not capitalize on the apparent influence they have on parental beliefs regarding mouthguard use. Efforts are needed by both health professionals and soccer organizations to educate parents about orofacial injuries and mouthguard use in competitive youth soccer

THE SPECTROSCOPY AND PHOTOPHYSICS OF π\pi HYDROGEN-BONDED COMPLEXES: BENZENE-CHCl3CHCl_{3}

Author Institution: Department of Chemistry, Purdue UniversityA vibronic level study of the spectroscopy and photophysics of the $C6H6-CHCl3$ complex has been carried out using a combination of laser-induced fluorescence and resonant two-photon ionization (R2Pl). In $C_{6}H_{6}-CHCl_{3}$, the $S1-S0$ origin remains forbidden while the $16^{1}_{0}$ transition is weakly induced. Neither $6^{1}_{0}$ nor $16^{1}_{0}$ are split by the presence of the $CHCl_{3}$ molecule. On this basis, a $C_{3v}$ structure is deduced for the complex, placing $CHCl_{3}$ on the six-fold axis of benzene. The large blue-shift of the complex's absorption relative to benzene $(+178 cm^{-1})$ and the efficient fragmentation of the complex following one-color R2Pl reflect a hydrogen-bonded orientation for $CHCl3$ relative to benzene's $\pi$ cloud. Dispersed fluorescence scans place a firm upper bound on the ground state binding energy of the complex of $2024cm^{-1}$. Both the $6^{1}$ and $6^{1} l^{1}$ leves do not dissociate on the time-scale of the $S_{1}$ fluorescence and show evidence of extensive state mixing with van der Waals' levels primarily built on the $0^{0}$ level of benzene. The $C_{6}H_{6} (CHCl_{3})_{2}$ cluster shows extensive intermolecular structure beginning at $+84 cm^{-1}$, a strong origin transition, and splitting of $6^{1}$. A structure which places both $CHCl_{3}$ molecules on the same side of the benzene ring is suggested on this basis. The vibronic level scheme used to deduce the structure of $C_{6}H_{6}-CHCl_{3}$ is tested against previous data on other $C_{6}H_{6}-X$ complexes. The scheme is found to be capable, in favorable cases, of deducing the structures of $C_{6}H_{6}-X$ complexes based purely on vibronic level data. Finally, the results on $C_{6}H_{6}-CHCl_{3}$ are compared with those on $C_{6}H_{6}-HCl$ and $C_{6}H_{6}-H_{2}O$ to evaluate the charaeteristics of the hydrogen bond

A Numerical Analysis of Shipboard and Coastal Zone Color Scanner Time Series of New Production Within Gulf Stream Cyclonic Eddies in the South Atlantic Bight

Eddy-induced upwelling occurs along the western edge of the Gulf Stream between Cape Canaveral, Florida, and Cape Hatteras, North Carolina, in the South Atlantic Bight (SAB). Coastal zone color scanner images of 1-km resolution spanning the period April 13-21, 1979, were processed to examine these eddy features in relation to concurrent shipboard and current/temperature measurements at moored arrays. A quasi-one-dimensional (z), time-dependent biological model, using only nitrate as a nutrient source, has been combined with a three-dimensional physical model in an attempt to replicate the observed phytoplankton field at the northward edge of an eddy. The model is applicable only to the SAB south of the Charleston Bump, at approximately 31.5-degrees-N, since no feature analogous to the bump exists in the model bathymetry. The modeled chlorophyll, nitrate, and primary production fields of the euphotic zone are very similar to those obtained from the satellite and shipboard data at the leading edges of the observed eddies south of the Charleston Bump. The horizontal and vertical simulated fluxes of nitrate and chlorophyll show that only approximately 10% of the upwelled nitrate is utilized by the phytoplankton of the modeled grid box on the northern edge of the cyclone, while approximately 75% is lost horizontally, with the remainder still in the euphotic zone after the 10-day period of the model. Loss of chlorophyll due-to sinking is very small in this strong upwelling region of the cyclone. The model is relatively insensitive to variations in the sinking parameterization and the external nitrate and chlorophyll fields but is very sensitive to a reduction of the maximum potential growth rate to half that measured. Given the success of this model in simulating the new production of the selected upwelling region, other upwelling regions for which measurements or successful models of physical and biological quantities and rates exist could be modeled similarly

AN EVALUATION OF THE FOOT TAPPING TEST (FTT) IN A HEALTHY POPULATION

Brian A. PribbleƗ1, Daniel J. Larsonǂ1, Christopher D. Blackǂ1, FACSM, Daniel J. BlackwoodƗ1 Jacob Rookard*1 and Rebecca D. Larsonǂ1 1University of Oklahoma, Norman, Oklahoma Simple in nature, the foot tapping test (FTT) has potential as an objective measure of upper motor function. Despite this, the reliability of the FTT has not been well identified. Furthermore, it is uncertain as to how to best measure the FTT as number of foot taps may vary upon counting methods. In order to make the FTT more clinically relevant, more research must be done on the FTT in healthy individuals in order to determine if it is a reliable measure of foot tapping ability. PURPOSE: The purpose of the study was to investigate reliability measures of the FTT in a healthy population using a variety of different measurement and counting methods. By identifying the reliability of the different measurement methods we hope to be able to make recommendations for future FTT research. METHODS: 20 healthy individuals, ages of 18-31, completed a series of foot tapping trials over 4 visits. While seated, subjects tapped their foot repeatedly for 10 seconds while researchers counted the number of foot taps. The starting foot was randomized for each visit and tested twice with the shoes ON and twice with shoes OFF (giving 8 trials per visit * 4 visits = 32 trials per subject). The number of foot taps was determined for each trial with visual inspection, video playback (slowed and normal speed), and with the use of a force plate. The mean values of the FTT trials were compared across days, dominant vs. non-dominant foot, the shoes ON/OFF conditions, and with the different counting methods. RESULTS: Significant differences were found in foot tapping rates in the shoes ON (mean: 54.3 taps) vs shoes OFF (mean: 53.4 taps) and dominant (mean: 53.2 taps) vs. non-dominant (mean: 51.1 taps) foot analyses (p\u3c0.05). Furthermore it was found that a significant difference in the mean number of foot taps existed between visit 1 (mean: 51.2 taps) and visits 2, 3, and 4 (mean: 54.3, 53.5, and 46.7 taps respectively) (p\u3e0.05). It was found that the FTT exhibited high test-retest reliability (Pearson r \u3e0.80) and high Cronbach’s alpha (alpha \u3e0.80) across the live, slowed video counts, and force plate measurements for both the shoes ON and shoes OFF trials. CONCLUSION: It was found that the FTT exhibits a high level of reliability across the live, slowed video, and force plate measures with both the shoes ON and shoes OFF. Given the observed reliability, the use of force plate with the FTT offers an attractive alternative to live counting or video playback methods