Judy R. Wilson

A toxicity index of skin and wound cleansers used on in vitro fibroblasts and keratinocytes.

OBJECTIVE: To determine toxicity indexes of commercially available skin, wound, and skin/wound cleansers on in vitro fibroblasts and keratinocytes. DESIGN: Seventeen cleansers and 3 liquid bath soaps were evaluated for cytotoxic effect on human infant dermal fibroblasts and epidermal keratinocytes. Both skin cell types were exposed to serial 10-fold dilutions of each cleanser until treated cell viability was comparable to untreated controls. RESULTS: The experimental design allowed calculation of relative toxicity indexes ranging from 0 to 100,000. Shur-Clens, SAF-Clens, and saline were found to be the least toxic to fibroblasts (toxicity index 0); Dial Antibacterial Soap and Ivory Liqui-Gel were the most toxic (toxicity index 100,000). Biolex, Shur-Clens, and Techni-Care were the least toxic to keratinocytes (toxicity index 0); hydrogen peroxide, modified Dakins solution, and povidone (10%) were found to be the most toxic (toxicity index 100,000). CONCLUSIONS: Successful cutaneous tissue repair depends on the viability of the principal cell types involved (fibroblasts and keratinocytes). Toxicity indexes provide helpful guidelines for subsequent in vivo evaluations and clinical applications. The study findings also suggest that judicious use of these supposedly innocuous agents should be considered in a clinical setting.

Clenbuterol: a substitute for anabolic steroids?

Clenbuterol is a recently popular drug used by athletes in many sports for its purported anabolic effects and reduction of subcutaneous fat. It is a beta-2 (beta 2) agonist prescribed overseas as a bronchodilator, but not approved for use in this country. It is on the banned substance list of the United States Olympic Committee. To avoid any erosion of confidence, physicians caring for athletes need accurate information regarding clenbuterol. Such information is unavailable within the routine medical environs. A review of the literature of animal husbandry reveals that this drug, when administered in doses far greater than those required for bronchodilation, does indeed increase the deposition rate of lean mass and retard adipose gain. There are no human studies available. Animal studies were conducted on laboratory and slaughter stock. No investigation into long-term cardiovascular side effects has been undertaken. The rate of extrapolation from animal studies to unsupervised human usage is alarming. If this category of drugs does preserve lean mass in humans, there are legitimate medical applications. Trials of efficacy and safety are needed.

Hyperbaric Oxygen Reduces the Progression and Accelerates the Regression of Atherosclerosis in Rabbits

We studied the effect of hyperbaric oxygen (HBO) treatment on the extent of diet-induced accumulation of lipid oxidation products in rabbit plasma and tissues, on plasma paraoxonase activity, and on the extent of progression and regression of atherosclerotic lesions in the rabbit aorta. HBO treatment of cholesterol-fed rabbits dramatically reduces the development of arterial lesions despite having little or no effect on plasma or individual lipoprotein cholesterol concentrations. Compared with no treatment in cholesterol-fed animals, HBO treatment also substantially reduces the accumulation of lipid oxidation products (conjugated dienes, trienes, and thiobarbituric acid-reactive substances) in plasma, in the low density lipoprotein and high density lipoprotein fractions of plasma, in the liver, and in the aortic tissues. In addition, HBO treatment prevents the decrease in plasma paraoxonase activity observed in rabbits fed cholesterol-rich diets. Similarly, in regression studies, HBO treatment has no effect on the rate of plasma (or lipoprotein) cholesterol decline but significantly accelerates aortic lesion regression compared with no treatment. Direct measures of aortic cholesterol content support these morphological observations. On the basis of these results, we conclude that repeated, but relatively short, exposure to HBO induces an antioxidant defense mechanism(s) that is responsible for retarding the development or accelerating the regression of atherosclerotic lesions.

Hyperbaric oxygen treatment decreases inflammation and mechanical hypersensitivity in an animal model of inflammatory pain.

Hyperbaric oxygen therapy has been used to treat a variety of ailments from carbon monoxide poisoning to fibromyalgia. The purpose of this experiment was to explore the effect of hyperbaric oxygen treatment on carrageenan-induced inflammation and pain in rats. Hyperbaric oxygen treatment significantly decreased inflammation and pain following carrageenan injection. Clinically hyperbaric oxygen may be used in situations where NSAIDS are contraindicated or in persistent cases of inflammation.

Hyperbaric Oxygen in the Treatment of Migraine With Aura

Cephalalgia is one of the most common medical complaints and the search continues for relief. Early treatments for migraine included inhalation of 100% oxygen. It has been theorized that the increased levels of oxygen in the blood act as an alpha‐adrenergic agent to alleviate headache pain through vasoconstriction and local metabolic effects. The presence of muscle tenderness during some migraine headaches has also been established. The purpose of this study was to document relief of cephalalgia through use of a visual analog pain scale, algometry, and manual palpation. Female subjects with confirmed migraine were randomly assigned to begin with either the control (100% oxygen, no pressure) or hyperbaric treatment (100% oxygen, pressure). Manual palpation and algometry of 10 sites were done, bilaterally, by a trained specialist. Pain was evaluated with a visual analog scale. Resolution of tenderness and edema following both treatments was observable by manual palpation while algometry showed no differences between the two. Subjective pain was significantly decreased following hyperbaric oxygen treatment but not following the control treatment. Results suggest that hyperbaric oxygen treatment reduces migraine headache pain and that the patients subjective assessment was the best indicator of relief.

Hyperbaric oxygen treatment decreases pain in two nerve injury models

Hyperbaric oxygen (HBO) treatment has been used clinically to treat a variety of ailments, including severe burns and carbon monoxide poisoning, and in research settings has produced promising results when used to treat animal models of inflammatory pain. However, studies examining neuropathic pain or nerve injury models have been limited to physiological assessments and not whether the pain condition improves. The purpose of this study was to evaluate the effect of HBO on two common models of neuropathic pain, L5 ligation and chronic constriction injury (CCI) of the sciatic nerve. Following surgical manipulations, animals demonstrating mechanical hyperalgesia were randomly assigned to either HBO treatment or control for 90min treatment sessions, after which mechanical sensitivity was assessed at 15min and 6h post. Daily HBO sessions, with assessments 15min post-treatment, continued for two weeks, followed by 5 days of assessment only. The results indicated that both models demonstrated significant improvement in response to treatment over the course of the two-week period, with CCI animals recovering more quickly and maintaining this recovery throughout the post-treatment period. Hyperbaric oxygen treatment appears to be successful in relieving neuropathic pain for an extended period of time, and future research should be aimed at investigating the precise mechanisms underlying this positive effect.

Effects of Pressure-Demand Respirator Wear on Physiological and Perceptual Variables during Progressive Exercise to Maximal Levels

Current regulations governing the certification of respiratory protective devices are based on data published in the early 1950s. The limited data base of this early work and documented increases in the average height of the population underscore the need for additional information concerning the parameters of certification. In the present study, a protocol using an inclined treadmill (0.5% grade every 12 sec) was used to test a heterogeneous population (n = 38). Through submaximal up to and including maximal exercise levels with and without respirator wear, maximal oxygen uptake (VO2max) was significantly greater (p less than 0.01) with the respirator (44.11 +/- 1.3 mL/kg.min) than without the respirator (42.18 +/- 1.4 mL/kg.min) while maximal ventilation volumes (VEmax) were not significantly different (with = 118.7 +/- 4 L/min; without 119.6 +/- 5 L/min). While peak inspired flows (PFI) with the respirator (268 +/- 7 L/min) were less than without the respirator (281 +/- 9 L/min), p greater than 0.05, the lower peak expired flow (PFE) with the respirator (289 +/- 12 L/min) than without the respirator (324 +/- 13 L/min), p less than 0.01, indicated a significant blunting effect of the respiratory flows by the expired resistance during exercise to maximal levels. Peak inspired pressures (PPi) with and without the respirator were not significantly different (p greater than 0.05). The negative values obtained within the facepiece of the respirator (-7.65 +/- 0.8 cmH2O), however, indicate that the positive pressure within the facepiece was lost, and respiratory protection may be compromised. Peak expired pressure with the respirator (13.05 +/- 0.7 cmH2O) was significantly greater than without the respirator (10.7 +/- 0.5 cmH2O) indicating that, despite a lower PFE, greater force was required to overcome the resistances of the respirator on expiration. The dyspnea index, an index of physiological effort; suggests that the subjects were working at a higher percentage of their respiratory reserve with the respirator (p less than 0.05) than without. Perceptually, subjects also felt that breathing with the respirator was more difficult (p less than 0.05). The maximum heart rate and the ratings of perceived exertion were not significantly different between the two tests at maximal exercise levels. Maximum oxygen uptake was considered reached when subjects attained a respiratory exchange ratio of at least 1.15, when a heart rate response at or greater than age-predicted maximum was achieved, when ratings of perceived exertion indicated exhaustion, and/or when the measure of VO2 had plateaued during the final minute of exercise.(ABSTRACT TRUNCATED AT 400 WORDS)

Clinical Pulmonary Function Tests as Predictors of Work Performance during Respirator Wear

The Occupational Safety and Health Administration (OSHA) mandate requiring medical information for respirator users provides the physician with little or no guidance as to what objective criteria may be valuable in assessing the workers ability to use a respirator safely. Therefore, the purpose of this study is to use the results of clinical pulmonary function testing to predict performance time on maximal- and endurance-type exercise tests. Respirator mask wear reduced clinical pulmonary function measures from 7%-15% from mouthpiece controls. The resistances of the mask reduced forced vital capacity by an average of 11.6% (0.65 L); forced expiratory volume in 1 sec by 7.3% (0.33 L); and maximum voluntary ventilation in 15 sec by 7.4% (12.4 L/min). Stepwise linear regression analysis was used to determine the clinical pulmonary function measures that were the best predictors of work performance. The MVV.25 with the respirator was determined to be the best predictor of maximal exercise performance both with and without the respirator. The difference in peak inspired flow with and without the respirator was the best predictor of performance time with the respirator during the endurance walk to exhaustion. Recommendations are made to the physician for procedures for determining a workers pulmonary capacity and calculating the effect of the respirator in reducing that capacity. This information then will allow the physician to determine safe levels of ventilation for a particular work task.

Effects of a Six-Week Randomized Training Program on Speed and Agility in Previously Trained Adolescent Males

Athletes are constantly searching for training regimens to gain performance advantages for competition. Protocols are designed to promote increases in performance over shortand longterm periods but, most of these protocols improve only specific variables such as strength or running speed but not overall performance. The purpose of this study was to determine if increases in speed performance could be seen using a randomized style of sports performance training on adolescents who were familiar with, and had previously trained, using this style. Eight-male subjects, mean age of 14.6±0.9 years, participated in this training study. Mean height and weight were 1.7 m±0.12 m and 77.6 kg±15.3 kg, respectively. The study consisted of 6 weeks of randomized sports performance training. Subjects participating in the study had at least 12 weeks of previous randomized sports performance training. Three performance assessments (Russian box, plank, and timed ladder) were conducted prior to the 1st week of training and after the 6th week. Girth measurements (arm, thigh, and chest) and weight were also assessed preand post-training. Following the 6 weeks of training, significant differences (p<0.05 two-tailed, paired t-test) were observed in all three performance assessments. Pre/ post measurements for the Russian box, plank, and timed ladder were 72.13±20.27 touches/91.13±30.99 touches, 239.86±194.67 seconds/346.57±272.09 seconds, and 281±39.62 seconds/255.75±33.23 seconds, respectively. No significant differences were seen in preand post-training subject weight or girth measurements (arm, thigh, and chest). Results support that randomized sports performance training can continue to increase performance in adolescents with previous training experience.

The Prevalence of Signs of Median Nerve Compression among College Students in Kinesiology

Purpose: The purpose of this study was to assess the prevalence of signs of Median Nerve Compression (MNC) among male and female college students. Methods: Forty-one Kinesiology majors, 24 males (58%) and 17 females (42%) completed surveys to assess the volume of physical activity, computer use, and distal upper extremity pain associated with these activities. Each participant was assessed for signs of MNC with the Phalen’s test, Tinel’s tap test, and the hand elevation test. Grip strength was measured by hand grip dynamometry and participants’ percentile norms were calculated. Results: Indications of MNC were present in 17% of participants, (6 males, 1 female). Fiftyone percent of students experienced computer-related hand and forearm musculoskeletal pain. Eighty-one percent of those had pain during extended computer use and 41% of students experienced occasional pain with physical activity. It is noteworthy that 85% of participants used the computer 4 hours per day or less. Also, with each category of computer use and physical activity, 93% of participants had not experienced pain in the last two weeks. Conclusion: Though none of these factors could be associated with MNC, the prevalence of symptoms was similar to carpal tunnel syndrome (14%) in the general population.