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Context: Managing a concussion injury should involve the incorporation of a multifaceted approach, including a vision assessment. The frontoparietal circuits and subcortical nuclei are susceptible to trauma from a concussion injury, leading to dysfunction of the vestibulo-ocular system. Research investigating the effect of cumulative subconcussive impacts on neurological function is still in its infancy, but repetitive head impacts may result in vestibular system dysfunction. This dysfunction could create visual deficits, predisposing the individual to further head trauma., Objective: The purpose of this study was to investigate the cumulative effect of subconcussive impacts on minimum perception time, static visual acuity, gaze stability, and dynamic visual acuity scores., Design: Prospective cohort., Setting: Division I university., Patients: Thirty-three Division I men's lacrosse players (age = 19.52 [1.20] y)., Intervention: Competitive lacrosse season., Main Outcome Measures: At the beginning and end of the season, the players completed a vestibulo-ocular reflex assessment, using the InVision™ system by Neurocom® to assess perception, static acuity, gaze stability, and dynamic visual acuity. Score differentials were correlated with the head impact exposure data collected via instrumented helmets., Results: A significant correlation was found between change in perception scores and total number of head impacts (r = .54), and between changes in dynamic visual acuity loss scores on the rightside and maximum rotational acceleration (r = .36). No statistical differences were found between preseason and postseason vestibulo-ocular reflex variables., Conclusions: Cumulative subconcussive impacts may negatively affect vestibulo-ocular reflex scores, resulting in decreased visual performance. This decrease in vestibulo-ocular function may place the athlete at risk of sustaining additional head impacts or other injuries.

Context: Assessment of upper cervical range of motion (UCROM) and mobility is commonly performed in the clinical setting for patients suffering from headache, neck pain, and vestibular dysfunction. Reliable and reproducible measurement of this motion is often difficult or too expensive to perform in the clinical setting. Smartphone applications using the device's internal gyroscope offer an easy and inexpensive means of measuring UCROM, but their reliability has not been reported in the literature., Objective: To assess the reliability of an inclinometer application installed on 2 different devices (iPhone 6 [IP] and android [AN]) and to measure UCROM in a healthy population., Design: Two examiners assessed passive UCROM. Each examiner was assigned to a specific smartphone, and a repeated-measures design consisting of 3 trials for each examiner-phone was performed. The order of testing was randomized, and the examiners were blinded to UCROM measures., Setting: Laboratory., Participants: A total of 38 subjects (19 females and 19 males; age: 23.8 [1.2] y) without pain or injury to the neck or spine for at least 3 months., Intervention: Each examiner passively flexed the head fully, rotated the head fully in 1 direction, and then in another. Peak rotation measures were recorded from each smartphone. Three trials were performed for each phone, with a 2-minute break between examiners/phones., Main Outcome Measures: Intraclass correlation coefficient using a 2-way mixed, absolute agreement model was obtained (1) between each examiner-phone and (2) within each examiner-phone for the measurements in each rotation direction., Results: Interphone/examiner reliability comparing average peak and total UCROM for each device was excellent (.87, .81). Intraphone/examiner reliability, determined across 3 trials, was also excellent (AN right rot. = .91, AN left rot. = .96; IP right rot. = .98, IP left rot. = .95)., Conclusion: UCROM can be reliably measured using a smartphone inclinometer application.

Objective: To evaluate the efficacy of an injury prevention and monitoring program implemented by athletic trainers to reduce workers compensation costs in a hospital system with multiple centers and locations., Methods: A retrospective analysis of workers compensation claims (ie, lost days, light days, and incurred costs) was performed to compare injury data from 2 years before to 2 years after the start of the program., Results: The program significantly reduced the organization's incurred costs by 46.7% (P = 0.031) and light days by 44% (P = 0.022). Lost days were found to decrease by 37%, however, this decrease was not statistically significant (P = 0.078)., Conclusions: Athletic trainers, using their knowledge of anatomy, biomechanics, ergonomics, injury management, and rehabilitation, can effectively prevent and reduce workers compensation costs in a multicenter hospital system.

This chapter describes the use of reversed-phase HPLC with multichannel coulometric electrochemical detection for the routine, sensitive, and simultaneous measurement of oxidized and reduced CoQ10 and CoQ9 in human plasma and serum. Analytes are first resolved chromatographically prior to electrochemical detection using three serially placed flow-through coulometric sensors set for oxidation-reduction-re-oxidation. Such electrochemical manipulation of analytes not only improves selectivity and specificity (decreasing the likelihood of co-elution), but also leads to improved sensitivity and decreased noise. The method is completed in ,18 min, shows excellent linearity, good intra-day (% RSD = 1.2-2.3) and inter-day (% RSD 2.2-3.9) precision, and has a limit of detection to low pg levels (on column). This approach was used to measure oxidized and reduced CoQ10 and CoQ9 in 30 human plasma samples, and oxidized and reduced CoQ10 in 10 human serum samples (NIST Micronutrients Measurement Quality Assurance Program for fat-soluble vitamins).

Intracellular free Zn(2+) is elevated in a variety of pathological conditions, including ischemia-reperfusion injury and Alzheimer's disease. Impairment of mitochondrial respiration is also associated with these pathological conditions. To test whether elevated Zn(2+) and impaired respiration might be linked, respiration of isolated rat liver mitochondria was measured after addition of Zn(2+). Zn(2+) inhibition (K(i)(app) = approximately 1 micrometer) was observed for respiration stimulated by alpha-ketoglutarate at concentrations well within the range of intracellular Zn(2+) reported for cultured hepatocytes. The bc(1) complex is inhibited by Zn(2+) (Link, T. A., and von Jagow, G. (1995) J. Biol. Chem. 270, 25001-25006). However, respiration stimulated by succinate (K(i)(app) = approximately 6 micrometer) was less sensitive to Zn(2+), indicating the existence of a mitochondrial target for Zn(2+) upstream from bc(1) complex. Purified pig heart alpha-ketoglutarate dehydrogenase complex was strongly inhibited by Zn(2+) (K(i)(app) = 0.37 +/- 0.05 micrometer). Glutamate dehydrogenase was more resistant (K(i)(app) = 6 micrometer), malate dehydrogenase was unaffected, and succinate dehydrogenase was stimulated by Zn(2+). Zn(2+) inhibition of alpha-ketoglutarate dehydrogenase complex required enzyme cycling and was reversed by EDTA. Reversibility was inversely related to the duration of exposure and the concentration of Zn(2+). Physiological free Zn(2+) may modulate hepatic mitochondrial respiration by reversible inhibition of the alpha-ketoglutarate dehydrogenase complex. In contrast, extreme or chronic elevation of intracellular Zn(2+) could contribute to persistent reductions in mitochondrial respiration that have been observed in Zn(2+)-rich diseased tissues.

A variety of biological samples such as blood, urine, hair, nail and kidneys has been analysed cadmium. Tantalum ribbon flameless and conventional flame-aspiration atomic-absorption techniques were employed for the analysis.