Comparison of protocols measuring diffusion and partition coefficients in the stratum corneum.

Partition (K) and diffusion (D) coefficients are important to measure for the modelling of skin penetration of chemicals through the stratum corneum (SC). We compared the feasibility of three protocols for the testing of 50 chemicals in our main studies, using three cosmetics-relevant model chemicals with a wide range of logP values. Protocol 1: SC concentration-depth profile using tape-stripping (measures KSC/v and DSC /HSC2 , where HSC is the SC thickness); Protocol 2A: incubation of isolated SC with chemical (direct measurement of KSC/v only) and Protocol 2B: diffusion through isolated SC mounted on a Franz cell (measures KSC/v and DSC /HSC2 , and is based on Fick's laws). KSC/v values for caffeine and resorcinol using Protocol 1 and 2B were within 30% of each other, values using Protocol 2A were ~two-fold higher, and all values were within 10-fold of each other. Only indirect determination of KSC/v by Protocol 2B was different from the direct measurement of KSC/v by Protocol 2A and Protocol 1 for 7-EC. The variability of KSC/v for all three chemicals using Protocol 2B was higher compared to Protocol 1 and 2A. DSC /HSC2 values for the three chemicals were of the same order of magnitude using all three protocols. Additionally, using Protocol 1, there was very little difference between parameters measured in pig and human SC. In conclusion, KSC/v, and DSC values were comparable using different methods. Pig skin might be a good surrogate for human skin for the three chemicals tested. Copyright © 2017 The Authors Journal of Applied Toxicology published by John Wiley & Sons Ltd.

Selective processing of body image words in women at-risk for developing an eating disorder: a preliminary study.

We evaluated the utility of the Modified Stroop task as a measure of body image concerns in women at-risk for an eating disorder. Data were collected among 31 participants from an eating disorder prevention program. The Modified Stroop was significantly associated with overeating episodes and an explicit measure of shape concern. The traditional Stroop effect was found while the Modified Stroop effect was non-significant. The results raise questions about the Modified Stroop task's utility in identifying at-risk women. Methodological and clinical implications are discussed.

Effect of desensitization in solid organ transplant recipients depends on some cytokines genes polymorphism.

Desensitization (DS) is widely used to decrease PRA in solid organs transplant candidates (TC). Various numbers of cycles of DS are required to reduce or eliminate donor specific antibodies (DSA). The goal of this study was to investigate if there was a correlation between polymorphism (PM) of some cytokine genes and intensity of DS required to make the recipient/donor cross match compatible. Thirty-one TCs were included in the study. Antibody specificity, percent of reactive antibodies (PRA) and serum concentration of cytokines were analyzed using the LUMINEX platform. PCR-SSP method was used for IL-1alpha, IL-1beta, IL-1R, IL-1Ralpha, IL-4Ralpha, IL-12, IFNgamma, TGFbeta1, TNFalpha, IL-2, IL-4, IL-6 and IL-10 gene PM analysis. Significant relationship between PM of genes encoding IL-4Ralpha, IFNgamma and IL-12 (p70) and susceptibility to DS was demonstrated (p=0.04, p=0.01 and p=0.05 respectively). Correlation between elevated serum level of IL-12 (p70) and A/A or C/A genotype at -1188 position was found in resistant to DS TCs (p=0.015). These results indicate that analysis PM of genes encoding IL-4R, IFNgamma and IL-12 enables to define the DS strategy in TCs more accurately regarding the number of plasmapheresis (PP) cycles and dose of intravenous immunoglobulin (IVIG).

Skin disease among Latino farmworkers in North Carolina.

An estimated 4.2 million seasonal and migrant farmworkers and their dependents live in the U.S. Most of these farmworkers are Latino. These workers are exposed to numerous occupational and environmental risk factors that can result in skin disease. Few data exist on the prevalence of skin disease in this population. The purpose of this study was to estimate the prevalence and predictors of skin disease in a sample of Latino farmworkers in North Carolina. A sample of 59 farmworkers was recruited and interviewed at two camps during the 2004 agricultural season. A dermatologist completed a skin exam of each worker and recorded any skin disease present. Forty-two (77.7%) of the 54 men, and all five of the women examined had a diagnosed skin disease. For the men, onychomycosis (nail fungus, 31.5%), tinea pedis (foot fungus, 27.8%), and acne (24.1 %) were the most commonly diagnosed skin diseases, with contact dermatitis diagnosed in 5.6% of the sample. Other diagnoses included scars, sunburn, and atopic dermatitis. Among the women, diagnoses included melasma (dark patches on the face, 2 cases), xerosis (excessively dry skin, 1 case), tinea pedis (2 cases), onychomycosis (1 case), acne (1 case), and insect bites (1 case). There were no statistically significant differences between workers in the two camps despite different growing seasons and different crops harvested. Skin disease is prevalent among the North Carolina Latino farmworkers who participated in this study, with fungal disease being the most prevalent.

An apparatus and method to characterize causes of positional plagiocephaly.

Positional plagiocephaly (misshapen head in infants) has increased dramatically in the United States since the beginning of the Back to Sleep program in 1992. In order to understand the increase due to repositioning from prone to supine position for sleep, we developed a home-based monitoring system to discern state of sleep and re-positioning frequency in infants. The portable system allows real-time logging of sleep position and patterns by a simplified sleep algorithm and association of sleep head position and movement which are time-stamped for correlation. Preliminary correlatory results suggest that plagiocephalic infants experience greater periods of rapid-eye-movement (REM) sleep than controls and show more narrow range of motion during sleep.

A provocative test to determine brain compliance in the management of patients with hydrocephalus.

Non-invasive techniques to explore intracranial compliance and pressure have been extensively explored in recent years. Previous techniques have used expensive technologies to make these measurements, often with difficulty. We present a novel, inexpensive method and algorithm to observe trends in intracranial compliance measurement targeted towards the treatment and management of hydrocephalus. The technique uses two photo-plethysmographic sensors to record arterial pulse perfusion, a common tilt table apparatus to methodically and artificially increase intracranial pressure, and a digital signal processing algorithm to determine phase difference between the waveforms. A secondary phase-difference disease signature approach is also hypothesized.

A signal analysis algorithm for determining brain compliance non-invasively.

Patients with increased intracranial pressure (ICP) caused by hydrocephalus or brain injury have poor brain compliance or increased brain stiffness. The condition is commonly treated by a surgical diversion of cerebrospinal fluid (CSF) through placement of a ventriculoperitoneal (VP) shunt. These inserted devices frequently fail and require replacement. Assessment of failed devices typically requires an invasive surgical procedure to implant an ICP sensor. Brain compliance can be determined non-invasively by comparing the intracranial pressure (ICP) waveform to the digital artery waveform. The ICP waveform is derived from a piezo sensor snugged into the external ear canal and worn as a headset. The digital artery waveform is derived from a stand pulse oximeter. Digital signal processing performed on sampled data from these two sensors shows a time-lag or phase relationship between the two waves which widens with worsening brain stiffness or compliance. An algorithm is presented that shows how these signals can be used to compute brain compliance. An instrument designed to calculate real-time brain compliance to aid healthcare professionals is described.

Alaska's model program for occupational injury prevention: applying surveillance for effective public health practice.

BACKGROUND: NIOSH established its Alaska Field Station in Anchorage, Alaska, in 1991, after identifying Alaska as America's highest-risk state for traumatic worker fatalities. Since then, NIOSH established comprehensive occupational injury surveillance in Alaska, and formed and facilitated interagency working groups (of state and federal agencies) and industry, labor, and professional organizations to address major factors leading to occupational death and injury in the state. STUDY DESIGN: Descriptive epidemiologic study of registry surveillance data obtained via direct on-site investigation of incidents and data-sharing with jurisdictional agencies. METHODS: We established a surveillance system, obtaining information via data-sharing with jurisdictional agencies and from direct on-site investigation of incidents. Also, we collaborate with state and regional government agencies, industry, workers, and non-governmental organizations to develop interventions. RESULTS: During 1991-1999, Alaska experienced a 50-percent overall decline in work-related deaths, including a substantial decline in commercial fishing deaths, and a very sharp decline in helicopter logging-related deaths. These efforts have lead to major national and international government-industry collaborative efforts in improving the safety of helicopter lift operations, and a concomitant improvement in fishing industry mortality rates among workers fishing Alaskan seas. CONCLUSIONS: Using surveillance data as information for action, these collaborative efforts have contributed to reducing Alaska's high occupational fatality rate. This reduction has been most clearly demonstrated in the rapidly expanding helicopter logging industry. The application of surveillance data also has played an important supportive role in the substantial progress made in reducing the mortality rate in Alaska's commercial fishing industry--historically, Alaska's (and America's) most dangerous industry, and the worst killer of Alaskan workers. Results suggest that extending Alaska's approach to occupational injury surveillance and prevention to other parts of the country, and application of these strategies to the entire spectrum of occupational injury hazards, could have a broad impact on reducing occupational injuries.

Controlled flight into terrain accidents among commuter and air taxi operators in Alaska.

BACKGROUND: Between 1990 and 1998, aviation accidents in Alaska caused 100 occupational pilot deaths (equivalent to 430/100,000 pilots/ year, approximately 86 times the overall U.S. worker fatality rate). Although Alaskan geography and climate increase aviation risks, many accidents were attributed to pilot error. While most accidents occurred during takeoff/landing, most fatalities resulted from Controlled Flight Into Terrain (CFIT). The purpose of this study was to examine risk factors for CFIT. METHODS: Using National Transportation Safety Board airplane accident data we identified CFIT from flight phase and event description fields, and calculated odds ratios for CFIT/non-CFIT accidents for visual conditions, aircraft features, and pilot experience. RESULTS: Between 1991 and 1998, 351 single aircraft commuter and air taxi accidents occurred in Alaska; 59 (17%) were CFIT. Of 140 total fatalities, 82 (59%) occurred in 30 CFIT accidents. There was a twelve-fold risk for death in CFIT vs. non-CFIT accidents (OR = 12.42, 95% CI = 8.19-18.88). Accidents while flying Visual Flight Rules (VFR) into poor visibility were more likely CFIT than non-CFIT (Odds ratio = 46.06, Confidence Interval = 19.32-112.46), and caused 37% of all deaths. Additionally, flights in Instrument Meteorological Conditions (IMC) were 47 times more likely to be CFIT than non-CFIT. No risk for CFIT was shown for flight hours, number of engines, passenger presence, or pilot age. All CFIT were attributed to pilot error, often for continuing VFR into poor visibility. CONCLUSION: CFIT caused most aviation deaths. Further research into human factors contributing to CFIT is needed. Implementation of global-positioning, ground-proximity/avoidance technology, might reduce CFIT incidence.

Massive bilateral phaeochromocytomas in association with Von Hippel Lindau syndrome in pregnancy.

We report a rare case of large bilateral phaeochromocytomas in pregnancy, found coincidentally by ultrasonography at 26 weeks' gestation, in a woman with a family history of Von Hippel Lindau syndrome. Further, we report maternal and fetal serum and amniotic fluid phenoxybenzamine levels from this case.

Alaska's model program for surveillance and prevention of occupational injury deaths.

The National Institute for Occupational Safety and Health (NIOSH) established its Alaska Field Station in Anchorage in 1991 after identifying Alaska as the highest-risk state for traumatic worker fatalities. Since then, the Field Station, working in collaboration with other agencies, organizations, and individuals, has established a program for occupational injury surveillance in Alaska and formed interagency working groups to address the risk factors leading to occupational death and injury in the state. Collaborative efforts have contributed to reducing crash rates and mortality in Alaska's rapidly expanding helicopter logging industry and have played an important supportive role in the substantial progress made in reducing the mortality rate in Alaska's commercial fishing industry (historically Alaska's and America's most dangerous industry). Alaska experienced a 46% overall decline in work-related acute traumatic injury deaths from 1991 to 1998, a 64% decline in commercial fishing deaths, and a very sharp decline in helicopter logging-related deaths. Extending this regional approach to other parts of the country and applying these strategies to the entire spectrum of occupational injury and disease hazards could have a broad effect on reducing occupational injuries.

Epidemiology of work-related aviation fatalities in Alaska, 1990-94.

Alaska, with less than one-half of 1% of the United States workforce, accounts for 9% of all occupational aviation fatalities nationally; 30% of all occupational fatalities in Alaska are related to aviation. To understand this high mortality, we investigated occupational aviation crashes to identify risk factors. Occupational aviation fatalities in Alaska during 1990-94 were examined using National Transportation Safety Board reports and merged with records from the Alaska Occupational Injury Surveillance System. There were 876 aircraft crashes; 407 (46%) were work-related. Occupational crashes were 2.2 times (CI: 1.5, 3.2) more likely to result in fatalities than non-occupational crashes. Risk factors identified included poor weather conditions defined as Instrument Meteorological Conditions (IMC). A crash during IMC was 5.3 times (CI: 3.5, 7.9) more likely to result in fatalities than crashes in other conditions. Of aircraft involved in fatal occupational incidents, 33% were not completely destroyed, allowing the potential for survivors. An estimated 30% reduction in fatalities could have occurred if current technology in occupant protection had been used.

Preventing deaths in Alaska's commercial fishing industry.

BACKGROUND AND PURPOSE: The arctic and sub-arctic waters of Alaska provide a very hazardous work setting, with special hazards posed by great distances, seasonal darkness, cold waters, high winds, brief fishing seasons, and icing. Our intent is to reduce the remarkably high occupational fatality rate (200/100,000/year in 1991-1992) among Alaska's commercial fishing workers. Over 90% of these deaths have been due to drowning or drowning plus hypothermia, primarily associated with vessel capsizings and sinkings. METHODS: Comprehensive surveillance for commercial fishing occupational fatalities was established during 1991 in Alaska. During 1990 through 1994, the U.S. Commercial Fishing Industry Vessel Safety Act of 1988 required the implementation of comprehensive prevention measures for all fishing vessels in offshore cold waters, including immersion suits and other personal flotation devices, survival craft (life rafts), emergency position-indicating radio beacons, and crew training in emergency response and first aid. Parallel to this, voluntary training efforts by nonprofit organizations have greatly increased. RESULTS: During 1990-1994, drowning was the leading cause of occupational death in Alaska. During this period, 117 fishers died, 101 of them from drowning or drowning/hypothermia. During 1991-1994, there was a substantial decrease in Alaskan commercial fishing-related deaths, from 34 in 1991 to 35 in 1992, 22 in 1993, and 10 in 1994. While man-overboard drownings and some other categories of deaths (falls, fires) have continued to occur, the most marked progress has been in vessel-related events. CONCLUSION: Specific measures tailored to prevent drowning in vessel capsizings and sinkings in Alaska's commercial fishing industry have been very successful so far. Additional efforts must be made to reduce the frequency of vessel events and to prevent man-overboard events and drownings associated with them.

Effective injury prevention using surveillance data: helicopter logging, Alaska, 1992-1995.

BACKGROUND AND PURPOSE: To reduce the fatality rate in helicopter sling-load logging in Alaska. These operations--on rugged terrain, due to environmental restrictions and economics--are an emerging technology application worldwide. During 1992 and 1993, crashes during these operations in Alaska resulted in multiple fatalities. METHODS: During 1992, comprehensive surveillance for these events was established, combining electronic media and interagency notification with active investigation to identify preventable risk factors. These data were applied in mid-1993 by an interagency working group, which included representatives of the Alaska Department of Health and Social Services, Alaska Department of Labor, Federal Aviation Administration, National Transportation, Safety Board, U.S. Coast Guard, Occupational Safety and Health Administration, U.S. Forest Service, and National Institute for Occupational Safety and Health. In response to surveillance data, consensus safety recommendations were developed. Working closely with industry, immediate improvements were made in worker training, work/rest cycles, and oversight. Surveillance results are being used to evaluate the effectiveness of interventions. On March 1-2, 1995, an international workshop was convened in Ketchikan, Alaska, to involve industry and government agencies in planning for durable prevention in this industry. RESULTS: In Alaska between January 1, 1992, and June 30, 1993, there were 6 helicopter crashes, with 9 fatal (4 in pilots) and 10 severe nonfatal injuries, out of only 25 helicopters flying in helicopter logging operations. Alaska logging helicopters thus had the extraordinarily high annual crash rate of 16% and a catastrophic pilot fatality rate of 5,000/100,000/year. Investigation revealed that all crashes involved improper operational and/or maintenance practices. Since these recommendations were implemented in July 1993, there have been no additional helicopter logging fatalities in Alaska through 1995. The 1995 meeting resulted in further recommendations, including more vigorous oversight; development of rigorous voluntary industry standards for equipment, maintenance, and training; exclusive use of multi-engine rotocraft; and more vigorous controls on alcohol and drug use in this industry.

Effectiveness of phosphate acquisition by juvenile cold-desert perennials from different patterns of fertile-soil microsites.

Phosphate uptake was measured for Artemisia tridentata, Agropyron desertorum and Pseudoroegneria spicata, three common perennial North American Great Basin species. Four patterns of nutrient-rich microsites were used in the experiments (different distances, densities and nutrient concentrations) All species were more efficient at taking up P from microsites nearest the plants than from more distant microsites. Artemisia and Agropyron acquired P more rapidly from the distant microsites when there was a larger number of microsites and, therefore, a greater probability of encounter. Uptake from the nearest microsites did not increase after 26 days, while uptake from distant microsites increased and was equal to uptake from the nearest microsites by the end of the experiment. Phosphate uptake was four to five times higher for Artemisia than for Agropyron on a shoot mass basis and seven to eight times greater than for Pseudoroegneria, which reflects species relative growth rates. Differences in shoot dry mass were significant among species, but little evidence was found for interspecific competition. Root density, root dry mass and P uptake in the upper part of the soil mixture was higher for Artemisia than the other species. Phosphate acquisition seems to be influenced by the distance of microsites and their density and the ability of plants to encounter and proliferate absorbing organs in the microsites.

Rapid physiological adjustment of roots to localized soil enrichment.

SOIL microsites rich in available nutrients are an important source of mineral nutrients for plants in many environments(1-5). Patchiness in nutrient availability below ground is analogous to resource availability in canopy gaps above ground(6). Although the physiological changes occurring in leaves exposed to sun and shade in canopy gaps are well known(7-9), we do not know any studies that show similar physiological changes in roots in enriched soil patches. Here we present evidence of large and rapid increases in the uptake kinetics of plant roots after creating nutrient-rich soil patches in the field. The mean rate of phosphate uptake at a given external phosphate concentration increased by as much as 80% for roots from enriched soil patches compared with roots of control patches treated with distilled water. The changes took place within days of patch treatment. This degree of plasticity was particularly notable for plants growing in soils of very low available phosphorus. These results showing rapid physiological plasticity of roots in fertile soil microsites have important implications for the theory and modelling of nutrient uptake in all soils.

Identification of vitamin E-dependent water soluble fluorescent compounds in mouse tissues.

The present paper describes the identification of two vitamin E-dependent, water soluble fluorescent compounds in mouse tissues. Ultraviolet and fluorescent spectroscopy, derivatization with 1-dimethylamino-naphthalene-5-sulfonyl chloride (dansyl chloride) and cochromatography using high performance liquid chromatography (HPLC) were utilized for the identification of the unknown compounds. The water soluble fluorescent compounds in mouse tissues were identified as tyrosine and tryptophan. The compounds were previously found to increase significantly in vitamin E deficiency in various tissues.

Malondialdehyde-containing proteins and their relationship to vitamin E.

A high molecular weight (Sephadex G-15 void volume), water-soluble, fluorescent material that was found to increase significantly in the mouse liver in response to vitamin E deficiency was separated into six proteins by high performance liquid chromatography (HPLC) using a TSK G2000 SW column. One of these proteins increased significantly in concentration due to vitamin E deficiency and had a molecular weight of 20,000 daltons. This protein was found to contain malondialdehyde, an end product of lipid peroxidation, attached to it presumably in a Schiff-base type structure with amino groups. This appears to be the first report in the literature of direct evidence that malondialdehyde is attached to protein in vivo.

Ozone-related fluorescent compounds in mouse liver and lung.

Groups of ten female, weanling mice were fed a basal, vitamin E-deficient diet or a basal diet supplemented with RRR-alpha-tocopheryl acetate for 14 months. During the last month one group from each dietary regimen was exposed for 30-60 min/day to 1.5 ppm ozone (25 hr total ozone exposure) and the remaining groups to control ambient air. The liver and lung tissues were homogenized and extracted with 2:1 chloroform:methanol and water. The water-soluble and organic solvent-soluble fluorescent materials were separated on Sephadex G-25 and LH-20 columns, respectively. Excitation and emission wavelengths for the eluting fractions were determined by continuous emission scans from 250 to 600 nm for each excitation wavelength between 250 and 500 nm (in increments of 25 nm). Ozone exposure did not effect the concentration of any of the fluorescent materials examined in the lung, but it resulted in a significant increase in two of four water-soluble compounds in the liver with excitation wavelength maxima/emission wavelength maxima of 270 nm/310 nm and 275 nm/350 nm (smaller molecular weight material) suggesting in vivo lipid oxidation.