Prolonged exposure to particulate chromate inhibits RAD51 nuclear import mediator proteins.

PubMed

Browning, Cynthia L; Wise, John Pierce

2017-09-15

Particulate hexavalent chromium (Cr(VI)) is a human lung carcinogen and a human health concern. The induction of structural chromosome instability is considered to be a driving mechanism of Cr(VI)-induced carcinogenesis. Homologous recombination repair protects against Cr(VI)-induced chromosome damage, due to its highly accurate repair of Cr(VI)-induced DNA double strand breaks. However, recent studies demonstrate Cr(VI) inhibits homologous recombination repair through the misregulation of RAD51. RAD51 is an essential protein in HR repair that facilitates the search for a homologous sequence. Recent studies show prolonged Cr(VI) exposure prevents proper RAD51 subcellular localization, causing it to accumulate in the cytoplasm. Since nuclear import of RAD51 is crucial to its function, this study investigated the effect of Cr(VI) on the RAD51 nuclear import mediators, RAD51C and BRCA2. We show acute (24h) Cr(VI) exposure induces the proper localization of RAD51C and BRCA2. In contrast, prolonged (120h) exposure increased the cytoplasmic localization of both proteins, although RAD51C localization was more severely impaired. These results correlate temporally with the previously reported Cr(VI)-induced RAD51 cytoplasmic accumulation. In addition, we found Cr(VI) does not inhibit interaction between RAD51 and its nuclear import mediators. Altogether, our results suggest prolonged Cr(VI) exposure inhibits the nuclear import of RAD51C, and to a lesser extent, BRCA2, which results in the cytoplasmic accumulation of RAD51. Cr(VI)-induced inhibition of nuclear import may play a key role in its carcinogenic mechanism since the nuclear import of many tumor suppressor proteins and DNA repair proteins is crucial to their function. Copyright © 2017 Elsevier Inc. All rights reserved.

Prolonged daily light exposure increases body fat mass through attenuation of brown adipose tissue activity

PubMed Central

Kooijman, Sander; van den Berg, Rosa; Ramkisoensing, Ashna; Boon, Mariëtte R.; Kuipers, Eline N.; Loef, Marieke; Zonneveld, Tom C. M.; Lucassen, Eliane A.; Sips, Hetty C. M.; Chatzispyrou, Iliana A.; Houtkooper, Riekelt H.; Meijer, Johanna H.; Coomans, Claudia P.; Biermasz, Nienke R.; Rensen, Patrick C. N.

2015-01-01

Disruption of circadian rhythmicity is associated with obesity and related disorders, including type 2 diabetes and cardiovascular disease. Specifically, prolonged artificial light exposure associates with obesity in humans, although the underlying mechanism is unclear. Here, we report that increasing the daily hours of light exposure increases body adiposity through attenuation of brown adipose tissue (BAT) activity, a major contributor of energy expenditure. Mice exposed to a prolonged day length of 16- and 24-h light, compared with regular 12-h light, showed increased adiposity without affecting food intake or locomotor activity. Mechanistically, we demonstrated that prolonged day length decreases sympathetic input into BAT and reduces β3-adrenergic intracellular signaling. Concomitantly, prolonging day length decreased the uptake of fatty acids from triglyceride-rich lipoproteins, as well as of glucose from plasma selectively by BAT. We conclude that impaired BAT activity is an important mediator in the association between disturbed circadian rhythm and adiposity, and anticipate that activation of BAT may overcome the adverse metabolic consequences of disturbed circadian rhythmicity. PMID:25964318

Media Impacts on Women's Fertility Desires: A Prolonged Exposure Experiment.

PubMed

Knobloch-Westerwick, Silvia; Willis, Laura E; Kennard, Ashley R

2016-06-01

Media exposure may have implications for family planning, a public health issue of key importance. Drawing on social comparison theory and social identity theory, a prolonged exposure experiment examined whether media portrayals of women's social roles affect fertility desires among 166 American, nonstudent, never married, childless women ages 21-35 years old. After sign-up and baseline sessions, participants viewed magazine pages five days in a row. Stimuli presented women in either mother/homemaker roles, beauty ideal roles, or professional roles. Three days later, participants again indicated their number of desired children and time planned until first birth. Exposure to mother/homemaker and beauty ideal portrayals increased the number of desired children across time. Exposure to professional portrayals increased the time planned until 1st birth compared to beauty ideal portrayals-this impact was partially mediated by a shift toward more progressive gender norms (per social identity theory) and assimilation (per social comparison theory).

Prolonged Exposure Therapy for Combat-Related Posttraumatic Stress Disorder: Comparing Outcomes for Veterans of Different Wars

PubMed Central

Yoder, Matthew; Tuerk, Peter W.; Price, Matthew; Grubaugh, Anouk L.; Strachan, Martha; Myrick, Hugh; Acierno, Ron

2012-01-01

There is significant support for exposure therapy as an effective treatment for posttraumatic stress disorder (PTSD) across a variety of populations, including veterans; however, there is little empirical information regarding how veterans of different war theaters respond to exposure therapy. Accordingly, questions remain regarding therapy effectiveness for treatment of PTSD for veterans of different eras. Such questions have important implications for the dissemination of evidence based treatments, treatment development, and policy. The current study compared treatment outcomes across 112 veterans of the Vietnam War, the first Persian Gulf War, and the wars in Afghanistan and Iraq. All subjects were diagnosed with PTSD and enrolled in Prolonged Exposure (PE) treatment. Veterans from all three groups showed significant improvement in PTSD symptoms, with veterans from Vietnam and Afghanistan/Iraq responding similarly to treatment. Persian Gulf veterans did not respond to treatment at the same rate or to the same degree as veterans from the other two eras. Questions and issues regarding the effectiveness of evidence based treatment for veterans from different eras are discussed. PMID:22449084

Prolonged exposure therapy for combat-related posttraumatic stress disorder: comparing outcomes for veterans of different wars.

PubMed

Yoder, Matthew; Tuerk, Peter W; Price, Matthew; Grubaugh, Anouk L; Strachan, Martha; Myrick, Hugh; Acierno, Ron

2012-02-01

There is significant support for exposure therapy as an effective treatment for posttraumatic stress disorder (PTSD) across a variety of populations, including veterans; however, there is little empirical information regarding how veterans of different war theaters respond to exposure therapy. Accordingly, questions remain regarding therapy effectiveness for treatment of PTSD for veterans of different eras. Such questions have important implications for the dissemination of evidence based treatments, treatment development, and policy. The current study compared treatment outcomes across 112 veterans of the Vietnam War, the first Persian Gulf War, and the wars in Afghanistan and Iraq. All subjects were diagnosed with PTSD and enrolled in prolonged exposure (PE) treatment. Veterans from all three groups showed significant improvement in PTSD symptoms, with veterans from Vietnam and Afghanistan/Iraq responding similarly to treatment. Persian Gulf veterans did not respond to treatment at the same rate or to the same degree as veterans from the other two eras. Questions and issues regarding the effectiveness of evidence based treatment for veterans from different eras are discussed.

Home cage locomotor changes in non-human primates after prolonged welding-fume exposure.

PubMed

Kim, Choong Yong; Sung, Jae Hyuck; Chung, Yong Hyun; Park, Jung Duck; Han, Jeong Hee; Lee, Jong Seong; Heo, Jeong Doo; Yu, Il Je

2013-12-01

To define the relationship between the brain concentration of manganese and neurological signs, such as locomotion, after prolonged welding-fume exposure, cynomolgus monkeys were acclimated for 1 month and then divided into three concentration groups: unexposed, low concentration (31 mg/m(3) total suspended particulate (TSP), 0.9 mg/m(3) of Mn), and high concentration (62 mg/m(3) TSP, 1.95 mg/m(3) of Mn) of TSP. The monkeys were exposed to manual metal-arc stainless steel (MMA-SS) welding fumes for 2 h per day over 8 months in an inhalation chamber system equipped with an automatic fume generator. The home cage locomotor activity and patterns were determined using a camera system over 2-4 consecutive days. After 25 and 32 weeks of exposure, the home cage locomotor activity of the high-concentration primates was found to be 5-6 times higher than that of the unexposed primates, and this increased locomotor activity was maintained for 7 weeks after ceasing the welding-fume exposure, eventually subsiding to three times higher after 13 weeks of recovery. Therefore, the present results, along with our previous observations of a high magnetic resonance imaging (MRI) T1 signal in the globus pallidus and increased blood Mn concentration, indicate that prolonged welding-fume exposure can cause neurobehavioral changes in cynomolgus monkeys.

Ozone exposure of a weed community produces adaptive changes in seed populations of Spergula arvensis.

PubMed

Landesmann, Jennifer B; Gundel, Pedro E; Martínez-Ghersa, M Alejandra; Ghersa, Claudio M

2013-01-01

Tropospheric ozone is one of the major drivers of global change. This stress factor alters plant growth and development. Ozone could act as a selection pressure on species communities composition, but also on population genetic background, thus affecting life history traits. Our objective was to evaluate the consequences of prolonged ozone exposure of a weed community on phenotypic traits of Spergulaarvensis linked to persistence. Specifically, we predicted that the selection pressure exerted by high ozone concentrations as well as the concomitant changes in the weed community would drive population adaptive changes which will be reflected on seed germination, dormancy and longevity. In order to test seed viability and dormancy level, we conducted germination experiments for which we used seeds produced by S. arvensis plants grown within a weed community exposed to three ozone treatments during four years (0, 90 and 120 ppb). We also performed a soil seed bank experiment to test seed longevity with seeds coming from both the four-year ozone exposure experiment and from a short-term treatment conducted at ambient and added ozone concentrations. We found that prolonged ozone exposure produced changes in seed germination, dormancy and longevity, resulting in three S. arvensis populations. Seeds from the 90 ppb ozone selection treatment had the highest level of germination when stored at 75% RH and 25 °C and then scarified. These seeds showed the lowest dormancy level when being subjected to 5 ºC/5% RH and 25 ºC/75% followed by 5% RH storage conditions. Furthermore, ozone exposure increased seed persistence in the soil through a maternal effect. Given that tropospheric ozone is an important pollutant in rural areas, changes in seed traits due to ozone exposure could increase weed persistence in fields, thus affecting weed-crop interactions, which could ultimately reduce crop production.

Ozone Exposure of a Weed Community Produces Adaptive Changes in Seed Populations of Spergula arvensis

PubMed Central

Landesmann, Jennifer B.; Gundel, Pedro E.; Martínez-Ghersa, M. Alejandra; Ghersa, Claudio M.

2013-01-01

Tropospheric ozone is one of the major drivers of global change. This stress factor alters plant growth and development. Ozone could act as a selection pressure on species communities composition, but also on population genetic background, thus affecting life history traits. Our objective was to evaluate the consequences of prolonged ozone exposure of a weed community on phenotypic traits of Spergula arvensis linked to persistence. Specifically, we predicted that the selection pressure exerted by high ozone concentrations as well as the concomitant changes in the weed community would drive population adaptive changes which will be reflected on seed germination, dormancy and longevity. In order to test seed viability and dormancy level, we conducted germination experiments for which we used seeds produced by S. arvensis plants grown within a weed community exposed to three ozone treatments during four years (0, 90 and 120 ppb). We also performed a soil seed bank experiment to test seed longevity with seeds coming from both the four-year ozone exposure experiment and from a short-term treatment conducted at ambient and added ozone concentrations. We found that prolonged ozone exposure produced changes in seed germination, dormancy and longevity, resulting in three S. arvensis populations. Seeds from the 90 ppb ozone selection treatment had the highest level of germination when stored at 75% RH and 25 °C and then scarified. These seeds showed the lowest dormancy level when being subjected to 5 ºC/5% RH and 25 ºC/75% followed by 5% RH storage conditions. Furthermore, ozone exposure increased seed persistence in the soil through a maternal effect. Given that tropospheric ozone is an important pollutant in rural areas, changes in seed traits due to ozone exposure could increase weed persistence in fields, thus affecting weed-crop interactions, which could ultimately reduce crop production. PMID:24086640

The inoculating role of previous exposure to potentially traumatic life events on coping with prolonged exposure to rocket attacks: A lifespan perspective.

PubMed

Palgi, Yuval; Gelkopf, Marc; Berger, Rony

2015-06-30

Relatively little research have addressed the effect of prolonged exposure to rocket attacks with a lifespan perspective and only a handful of these studies focused on the effect of this exposure as a function of aging. The present study examined the effects of seven years of rocket attacks fired toward the south of Israel on adult participants of different ages. We examined whether potentially traumatic life events (PTLEs) unrelated to rocket attacks moderated the association between post-traumatic stress (PTS) symptoms and age. Data were obtained from a 2007 telephone survey using the Random Digit Dialing method and including 343 individuals (76.7% participation rate). Exposure to rockets, PTLEs, global distress, and post-traumatic symptomatology were assessed. Older age was associated with a higher level of PTS symptoms. Higher PTLE levels attenuated the association between age and PTS symptoms. Our results suggest that age is a risk factor for developing PTS symptoms under prolonged exposure to rocket attacks. However, previous levels of exposure to other negative events, as well as gender, appear to inoculate a person to stress, thus modulating the age-PTS association. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Prolonged Exposure versus Dynamic Therapy for Adolescent PTSD: A Pilot Randomized Controlled Trial

ERIC Educational Resources Information Center

Gilboa-Schechtman, Eva; Foa, Edna B.; Shafran, Naama; Aderka, Idan M.; Powers, Mark B.; Rachamim, Lilach; Rosenbach, Lea; Yadin, Elna; Apter, Alan

2010-01-01

Objective: To examine the efficacy and maintenance of developmentally adapted prolonged exposure therapy for adolescents (PE-A) compared with active control time-limited dynamic therapy (TLDP-A) for decreasing posttraumatic and depressive symptoms in adolescent victims of single-event traumas. Method: Thirty-eight adolescents (12 to 18 years old)…

Protection of the public in situations of prolonged radiation exposure. The application of the Commission's system of radiological protection to controllable radiation exposure due to natural sources and long-lived radioactive residues.

PubMed

1999-01-01

This report provides guidance on the application of the ICRP system of radiological protection to prolonged exposure situations affecting members of the public. It addresses the general application of the Commission's system to the control of prolonged exposures resulting from practices and to the undertaking of interventions in prolonged exposure situations. Additionally, it provides recommendations on generic reference levels for such interventions. The report also considers some specific situations and discusses a number of issues that have been of concern, namely: natural radiation sources that may give rise to high doses; the restoration and rehabilitation of sites where human activities involving radioactive substances have been carried out; the return to 'normality' following an accident that has released radioactive substances to the environment; and the global marketing of commodities for public consumption that contain radioactive substances. Annexes provide some examples of prolonged exposure situations and discuss the radiological protection quantities, radiation-induced health effects and aspects of the Commission's system of radiological protection relevant to prolonged exposure. Quantitative recommendations for prolonged exposures are provided in the report. They must be interpreted with extreme caution; Chapters 4 and 5 stress the upper bound nature of the following values: Generic reference levels for intervention, in terms of existing total annual doses, are given as < approximately 100 mSv, above which intervention is almost always justifiable (situations for which the annual dose threshold for deterministic effects in relevant organs is exceeded will almost always require intervention), and < approximately 10 mSv, below which intervention is not likely to be justifiable (and above which it may be necessary). Intervention exemption levels for commodities, especially building materials, are expressed as an additional annual dose of approximately 1

Physiological Stress Responses to Prolonged Exposure to MS-222 and Surgical Implantation in Juvenile Chinook Salmon

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wagner, Katie A.; Woodley, Christa M.; Seaburg, Adam

While many studies have investigated the effects of transmitters on fish condition, behavior, and survival, to our knowledge, no studies have taken into account anesthetic exposure time in addition to tag and surgery effects. We investigated stress responses to prolonged MS-222 exposure after stage 4 induction in surgically implanted juvenile Chinook salmon (Oncorhynchus tshawytscha). Survival, tag loss, plasma cortisol concentration, and blood Na +, K +, Ca 2+, and pH were measured immediately following anesthetic exposure and surgical implantation and 1, 7, and 14 days post-treatment. Despite the prolonged anesthetic exposure, 3-15 minutes post Stage 4 induction, there were nomore » mortalities or tag loss in any treatment. MS-222 was effective at delaying immediate cortisol release during surgical implantation; however, osmotic disturbances resulted, which were more pronounced in longer anesthetic time exposures. From day 1 to day 14, Na +, Ca 2+, and pH significantly decreased, while cortisol significantly increased. The cortisol increase was exacerbated by surgical implantation. There was a significant interaction between MS-222 time exposure and observation day for Na +, Ca 2+, K +, and pH; variations were seen in the longer time exposures, although not consistently. In conclusion, stress response patterns suggest stress associated with surgical implantation is amplified with increased exposure to MS-222.« less

Physical Simulation of a Prolonged Plasma-Plume Exposure of a Space Debris Object

NASA Astrophysics Data System (ADS)

Shuvalov, V. A.; Gorev, N. B.; Tokmak, N. A.; Kochubei, G. S.

2018-05-01

A methodology has been developed for the physical (laboratory) simulation of the prolonged exposure of a space debris object to high-energy ions of a plasma plume for removing the object into low-Earth orbit with its subsequent burning in the Earth's atmosphere. The methodology is based on the equivalence criteria of two modes of exposure (in the Earth's ionosphere and in the setup) and the procedure for accelerated resource tests in terms of the sputtering of the space debris material and its deceleration by a plasma jet in the Earth's ionosphere.

Prolonged Exposure Therapy for a Vietnam Veteran with PTSD and Early-Stage Dementia

ERIC Educational Resources Information Center

Duax, Jeanne M.; Waldron-Perrine, Brigid; Rauch, Sheila A. M.; Adams, Kenneth M.

2013-01-01

Although prolonged exposure therapy (PE) is considered an evidence-based treatment for PTSD, there has been little published about the use of this treatment for older adults with comorbid early-stage dementia. As the number of older adults in the United States continues to grow, so will their unique mental health needs. The present article…

Drug-induced QT interval prolongation: does ethnicity of the thorough QT study population matter?

PubMed Central

Shah, Rashmi R

2013-01-01

Inter-ethnic differences in drug responses have been well documented. Drug-induced QT interval prolongation is a major safety concern and therefore, regulatory authorities recommend a clinical thorough QT study (TQT) to investigate new drugs for their QT-prolonging potential. A positive study, determined by breach of a preset regulatory threshold, significantly influences late phase clinical trials by requiring intense ECG monitoring. A few studies that are currently available, although not statistically conclusive at present, question the assumption that ethnicity of the study population may not influence the outcome of a TQT study. Collective consideration of available pharmacogenetic and clinical information suggests that there may be inter-ethnic differences in QT-prolonging effects of drugs and that Caucasians may be more sensitive than other populations. The information also suggest s that (a) these differences may depend on the QT-prolonging potency of the drug and (b) exposure–response (E–R) analysis may be more sensitive than simple changes in QTc interval in unmasking this difference. If the QT response in Caucasians is generally found to be more intense than in non-Caucasians, there may be significant regulatory implications for domestic acceptance of data from a TQT study conducted in foreign populations. However, each drug will warrant an individual consideration when extrapolating the results of a TQT studyfrom one ethnic population to another and the ultimate clinical relevance of any difference. Further adequately designed and powered studies, investigating the pharmacologic properties and E–R relationships of additional drugs with different potencies, are needed in Caucasians, Oriental/Asian and African populations before firm conclusions can be drawn. PMID:22882246

Cognitive functions and cerebral oxygenation changes during acute and prolonged hypoxic exposure.

PubMed

Davranche, Karen; Casini, Laurence; Arnal, Pierrick J; Rupp, Thomas; Perrey, Stéphane; Verges, Samuel

2016-10-01

The present study aimed to assess specific cognitive processes (cognitive control and time perception) and hemodynamic correlates using functional near-infrared spectroscopy (fNIRS) during acute and prolonged high-altitude exposure. Eleven male subjects were transported via helicopter and dropped at 14 272 ft (4 350 meters) of altitude where they stayed for 4 days. Cognitive tasks, involving a conflict task and temporal bisection task, were performed at sea level the week before ascending to high altitude, the day of arrival (D0), the second (D2) and fourth (D4) day at high altitude. Cortical hemodynamic changes in the prefrontal cortex (PFC) area were monitored with fNIRS at rest and during the conflict task. Results showed that high altitude impacts information processing in terms of speed and accuracy. In the early hours of exposure (D0), participants displayed slower reaction times (RT) and decision errors were twice as high. While error rate for simple spontaneous responses remained twice that at sea level, the slow-down of RT was not detectable after 2 days at high-altitude. The larger fNIRS responses from D0 to D2 suggest that higher prefrontal activity partially counteracted cognitive performance decrements. Cognitive control, assessed through the build-up of a top-down response suppression mechanism, the early automatic response activation and the post-error adjustment were not impacted by hypoxia. However, during prolonged hypoxic exposure the temporal judgments were underestimated suggesting a slowdown of the internal clock. A decrease in cortical arousal level induced by hypoxia could consistently explain both the slowdown of the internal clock and the persistence of a higher number of errors after several days of exposure. Copyright © 2016 Elsevier Inc. All rights reserved.

Service utilization following participation in cognitive processing therapy or prolonged exposure therapy for post-traumatic stress disorder.

PubMed

Meyers, Laura L; Strom, Thad Q; Leskela, Jennie; Thuras, Paul; Kehle-Forbes, Shannon M; Curry, Kyle T

2013-01-01

This study evaluated the impact of a course of prolonged exposure or cognitive processing therapy on mental health and medical service utilization and health care service costs provided by the Department of Veterans Affairs (VA). Data on VA health service utilization and health care costs were obtained from national VA databases for 70 veterans who completed prolonged exposure or cognitive processing therapy at a Midwestern VA medical center. Utilization of services and cost data were examined for the year before and after treatment. Results demonstrated a significant decrease in the use of individual and group psychotherapy. Direct costs associated with mental health care decreased by 39.4%. Primary care and emergency department services remained unchanged.

Neural Circuits via Which Single Prolonged Stress Exposure Leads to Fear Extinction Retention Deficits

ERIC Educational Resources Information Center

Knox, Dayan; Stanfield, Briana R.; Staib, Jennifer M.; David, Nina P.; Keller, Samantha M.; DePietro, Thomas

2016-01-01

Single prolonged stress (SPS) has been used to examine mechanisms via which stress exposure leads to post-traumatic stress disorder symptoms. SPS induces fear extinction retention deficits, but neural circuits critical for mediating these deficits are unknown. To address this gap, we examined the effect of SPS on neural activity in brain regions…

Prolonged exposure of mixed aerobic cultures to low temperature and benzalkonium chloride affect the rate and extent of nitrification.

PubMed

Yang, Jeongwoo; Tezel, Ulas; Li, Kexun; Pavlostathis, Spyros G

2015-03-01

The combined effect of benzalkonium chloride (BAC) and prolonged exposure to low temperature on nitrification was investigated. Ammonia oxidation at 22-24°C by an enriched nitrifying culture was inhibited at increasing BAC concentrations and ceased at 15 mg BAC/L. The non-competitive inhibition coefficient was 1.5±0.9 mg BAC/L. Nitrification tests were conducted without and with BAC at 5mg/L using an aerobic, mixed heterotrophic/nitrifying culture maintained at a temperature range of 24-10°C. Maintaining this culture at 10°C for over one month in the absence of BAC, resulted in slower nitrification kinetics compared to those measured when the culture was first exposed to 10°C. BAC was degraded by the heterotrophic population, but its degradation rate decreased significantly as the culture temperature decreased to 10°C. These results confirm the negative impact of quaternary ammonium compounds on the nitrification process, which is further exacerbated by prolonged, low temperature conditions. Copyright © 2014 Elsevier Ltd. All rights reserved.

Response of Escherichia coli to Prolonged Berberine Exposure.

PubMed

Budeyri Gokgoz, Nilay; Avci, Fatma Gizem; Yoneten, Kubra Karaosmanoglu; Alaybeyoglu, Begum; Ozkirimli, Elif; Sayar, Nihat Alpagu; Kazan, Dilek; Sariyar Akbulut, Berna

2017-07-01

Berberine is a plant-derived alkaloid possessing antimicrobial activity; unfortunately, its efflux through multidrug resistance pumps reduces its efficacy. Cellular life span of Escherichia coli is generally shorter with prolonged berberine exposure; nevertheless, about 30% of the cells still remain robust following this treatment. To elucidate its mechanism of action and to identify proteins that could be involved in development of antimicrobial resistance, protein profiles of E. coli cells treated with berberine for 4.5 and 8 hours were compared with control cells. A total of 42 proteins were differentially expressed in cells treated with berberine for 8 hours when compared to control cells. In both 4.5 and 8 hours of berberine-treated cells, carbohydrate and peptide uptake regimens remained unchanged, although amino acid maintenance regimen switched from transport to synthesis. Defect in cell division persisted and this condition was confirmed by images obtained from scanning electron microscopy. Universal stress proteins were not involved in stress response. The significant increase in the abundance of elongation factors could suggest the involvement of these proteins in protection by exhibiting chaperone activities. Furthermore, the involvement of the outer membrane protein OmpW could receive special attention as a protein involved in response to antimicrobial agents, since the expression of only this porin protein was upregulated after 8 hours of exposure.

Does virtual reality increase emotional engagement during exposure for PTSD? Subjective distress during prolonged and virtual reality exposure therapy.

PubMed

Reger, Greg M; Smolenski, Derek; Norr, Aaron; Katz, Andrea; Buck, Benjamin; Rothbaum, Barbara O

2018-06-08

Prolonged exposure (PE) is a treatment for posttraumatic stress disorder (PTSD) based on emotional processing theory. According to this theory, emotional engagement during imaginal exposure is critical to clinical outcome. One rationale for virtual reality exposure therapy (VRE) is the ability of trauma-relevant, multi-sensory stimuli to increase emotional engagement. This study compared the subjective distress of active duty soldiers (N = 108) during exposure via PE or VRE. Soldiers with higher mean or peak distress during the first imaginal exposure had higher baseline PTSD symptom severity. There was no difference between groups on average or peak distress during imaginal exposure at the first or final exposure session. There were no significant differences in between-session habituation observed between VRE and PE groups. However, each ten-point decrease in SUDS scores, either mean or peak, from the initiation of imaginal exposure to the end of treatment, was associated with a greater decrease in CAPS-W scores for both groups. There were no group differences in these trajectories or the magnitude of the association between distress/habituation, and PTSD symptoms. Future research on VRE should measure patient ratings of engagement during exposure to better understand which patients are aided by this innovative approach to treatment. Published by Elsevier Ltd.

Prolonged Exposure for Guilt and Shame in a Veteran of Operation Iraqi Freedom

PubMed Central

Paul, Lisa A.; Gros, Daniel F.; Strachan, Martha; Worsham, Glenna; Foa, Edna B.; Acierno, Ron

2014-01-01

Morally injurious events appear capable of producing posttraumatic stress disorder (PTSD), even though they may not involve actual or perceived life-threat or a response of fear, horror, or helplessness. Researchers have questioned whether exposure therapies can address these events. The current report presents evidence of the effectiveness of this treatment approach for addressing posttraumatic symptoms related to a morally injurious event through an illustrative case of an Operation Iraqi Freedom veteran with PTSD characterized by symptoms of guilt and shame. The veteran was successfully treated with nine sessions of prolonged exposure therapy, reporting minimal PTSD symptoms one week post-treatment and at a six-month follow-up assessment. Implications for the treatment of veterans with significant guilt and shame using exposure-based therapies, and with respect to the recent changes to the diagnostic criteria for PTSD, are discussed. PMID:25505798

Virtual reality exposure versus prolonged exposure for PTSD: Which treatment for whom?

PubMed

Norr, Aaron M; Smolenski, Derek J; Katz, Andrea C; Rizzo, Albert A; Rothbaum, Barbara O; Difede, JoAnn; Koenen-Woods, Patricia; Reger, Mark A; Reger, Greg M

2018-06-01

The majority of studies comparing active psychological treatments for posttraumatic stress disorder (PTSD) do not find significant differences at posttreatment. This was the case in a recent trial examining prolonged exposure (PE) and virtual reality exposure (VRE) among active-duty soldiers with combat-related PTSD. Matching individual patients to specific treatments provides a potential avenue to improve significantly the public health impact of effective treatments for PTSD. A composite moderator approach was used to identify profiles of patients who would see superior PTSD symptom reduction in VRE or PE to inform future treatment matching. Active duty U.S. army soldiers (N = 108) were enrolled in a randomized clinical trial comparing VRE and PE in the treatment of PTSD stemming from deployments to Iraq or Afghanistan. Eighteen baseline variables were examined to identify treatment response heterogeneity in two patient groups: those with a superior response to PE and those with a superior response to VRE. The final composite moderator comprised four of 18 baseline variables. Results revealed that patients who were predicted to see greater PTSD symptom reduction in VRE were likely to be younger, not taking antidepressant medication, had greater PTSD hyperarousal symptoms, and were more likely to have greater than minimal suicide risk. Results suggest that treatment matching based on patient profiles could meaningfully improve treatment efficacy for combat-related PTSD. Future research can build on these results to improve our understanding of how to improve treatment matching for PTSD. © 2018 Wiley Periodicals, Inc.

FEASIBILITY AND EFFECTIVENESS OF DYADIC PROLONGED EXPOSURE INTERVENTION FOR PREVENTING POSTTRAUMATIC GRIEF IN YOUNG CHILDREN: A CASE REPORT OF TWO SIBLINGS.

PubMed

Rachamim, Lilach

2017-09-01

This article highlights the feasibility of a dyadic prolonged exposure (DPE) intervention (L. Rachamim, I. Mirochnik, L. Helpman, N. Nacasch, & E. Yadin, ) in a 3-year-old preschooler and in a 6-year-old kindergartener immediately following the traumatic death of their younger sibling. It presents a detailed case description of the DPE treatment addressing traumatic grief and includes transcribed treatment dialogue. At the time of treatment termination, both children and caregivers resumed normal functioning. The results suggest that DPE intervention may ameliorate posttraumatic grief symptoms in young children. Controlled studies of preventive interventions for this population are clearly warranted. © 2017 Michigan Association for Infant Mental Health.

Prolonged Exposure Treatment of Chronic PTSD in Juvenile Sex Offenders: Promising Results from Two Case Studies

ERIC Educational Resources Information Center

Hunter, John A.

2010-01-01

Prolonged exposure (PE) was used to treat chronic PTSD secondary to severe developmental trauma in two adolescent male sex offenders referred for residential sex offender treatment. Both youth were treatment resistant prior to initiation of PE and showed evidence of long-standing irritability and depression/anxiety. Clinical observation and…

Direction of Influence between Posttraumatic and Depressive Symptoms during Prolonged Exposure Therapy among Children and Adolescents

ERIC Educational Resources Information Center

Aderka, Idan M.; Foa, Edna B.; Applebaum, Edna; Shafran, Naama; Gilboa-Schechtman, Eva

2011-01-01

Objective: Our objective in the present study was to examine the temporal sequencing of posttraumatic and depressive symptoms during prolonged exposure therapy for posttraumatic stress disorder (PTSD) among children and adolescents. Method: Participants were 73 children and adolescents (56.2% female) between the ages of 8 and 18. Participants…

Potential Adverse Effects of Prolonged Sevoflurane Exposure on Developing Monkey Brain: From Abnormal Lipid Metabolism to Neuronal Damage.

PubMed

Liu, Fang; Rainosek, Shuo W; Frisch-Daiello, Jessica L; Patterson, Tucker A; Paule, Merle G; Slikker, William; Wang, Cheng; Han, Xianlin

2015-10-01

Sevoflurane is a volatile anesthetic that has been widely used in general anesthesia, yet its safety in pediatric use is a public concern. This study sought to evaluate whether prolonged exposure of infant monkeys to a clinically relevant concentration of sevoflurane is associated with any adverse effects on the developing brain. Infant monkeys were exposed to 2.5% sevoflurane for 9 h, and frontal cortical tissues were harvested for DNA microarray, lipidomics, Luminex protein, and histological assays. DNA microarray analysis showed that sevoflurane exposure resulted in a broad identification of differentially expressed genes (DEGs) in the monkey brain. In general, these genes were associated with nervous system development, function, and neural cell viability. Notably, a number of DEGs were closely related to lipid metabolism. Lipidomic analysis demonstrated that critical lipid components, (eg, phosphatidylethanolamine, phosphatidylserine, and phosphatidylglycerol) were significantly downregulated by prolonged exposure of sevoflurane. Luminex protein analysis indicated abnormal levels of cytokines in sevoflurane-exposed brains. Consistently, Fluoro-Jade C staining revealed more degenerating neurons after sevoflurane exposure. These data demonstrate that a clinically relevant concentration of sevoflurane (2.5%) is capable of inducing and maintaining an effective surgical plane of anesthesia in the developing nonhuman primate and that a prolonged exposure of 9 h resulted in profound changes in gene expression, cytokine levels, lipid metabolism, and subsequently, neuronal damage. Generally, sevoflurane-induced neuronal damage was also associated with changes in lipid content, composition, or both; and specific lipid changes could provide insights into the molecular mechanism(s) underlying anesthetic-induced neurotoxicity and may be sensitive biomarkers for the early detection of anesthetic-induced neuronal damage. Published by Oxford University Press on behalf of the

Increased risk of QT prolongation associated with atherosclerotic diseases in arseniasis-endemic area in southwestern coast of Taiwan

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, C.-H.; Chen, C.-L.; Hsiao, C.K.

2009-09-15

Chronic arsenic exposure has been documented to be associated with various cardiovascular diseases. We aimed to investigate 1) the increased risk of QT prolongation in chronic arsenic exposure, and 2) the relationships of cardiac repolarization (QT interval duration) with ischemic heart disease and carotid atherosclerosis. We studied 280 men and 355 women living in the endemic area of arseniasis in southwestern Taiwan. QT intervals in electrocardiogram and carotid intima-media thickness (IMT) by ultrasonography were measured. Ischemic heart disease was diagnosed by history or abnormal electrocardiogram. Significant associations of the corrected QT interval (QTc) duration with ischemic heart disease and carotidmore » intima-medium thickness and plaque were observed after adjustment for various risk factors in the multiple linear regression analysis (all p values < 0.05). Three indices of chronic arsenic exposure were all significantly associated with the risk of QTc prolongation showing dose-response relationships (p < 0.001). Chronic arsenic exposure was dose-dependently associated with the risk of QTc prolongation. Ischemic heart disease and carotid atherosclerosis were significantly associated with QTc intervals in chronic arsenic exposure. QTc prolongation might be suggested as an early biomarker for ischemic heart disease or carotid atherosclerosis in population with previous exposure to arsenic.« less

Short and prolonged exposure to hyperglycaemia in human fibroblasts and endothelial cells: metabolic and osmotic effects.

PubMed

Moruzzi, Noah; Del Sole, Marianna; Fato, Romana; Gerdes, Jantje M; Berggren, Per-Olof; Bergamini, Christian; Brismar, Kerstin

2014-08-01

High blood glucose levels are the main feature of diabetes. However, the underlying mechanism linking high glucose concentration to diabetic complications is still not fully elucidated, particularly with regard to human physiology. Excess of glucose is likely to trigger a metabolic response depending on the cell features, activating deleterious pathways involved in the complications of diabetes. In this study, we aim to elucidate how acute and prolonged hyperglycaemia alters the biology and metabolism in human fibroblasts and endothelial cells. We found that hyperglycaemia triggers a metabolic switch from oxidative phosphorylation to glycolysis that is maintained over prolonged time. Moreover, osmotic pressure is a major factor in the early metabolic response, decreasing both mitochondrial transmembrane potential and cellular proliferation. After prolonged exposure to hyperglycaemia we observed decreased mitochondrial steady-state and uncoupled respiration, together with a reduced ATP/ADP ratio. At the same time, we could not detect major changes in mitochondrial transmembrane potential and reactive oxygen species. We suggest that the physiological and metabolic alterations observed in healthy human primary fibroblasts and endothelial cells are an adaptive response to hyperglycaemia. The severity of metabolic and bioenergetics impairment associated with diabetic complications may occur after longer glucose exposure or due to interactions with cell types more sensitive to hyperglycaemia. Copyright © 2014 Elsevier Ltd. All rights reserved.

Media exposure and prolonged grief: A study of bereaved parents and siblings after the 2011 Utøya Island terror attack.

PubMed

Kristensen, Pål; Dyregrov, Kari; Dyregrov, Atle; Heir, Trond

2016-11-01

After terror attacks, the media coverage can be a potential secondary stressor for bereaved families. In the present study, we aimed to examine the level of prolonged grief (PG), and to explore the association between media exposure and PG in parents and siblings of individuals who were killed in a terror attack. Parents and siblings (n = 103) from 42 different families bereaved by the 2011 Utøya Island mass shooting participated in a survey 18 months after the attack. The survey measured the amount of media exposure experienced by the bereaved during the first month after the attack. PG was self-reported using the Inventory of Complicated Grief (ICG). Data was analyzed with multilevel methods with mixed effects models. Of the total sample of participants, 78.6% (n = 81/103) had sum scores higher than the designated cutoff >25 on ICG, indicating a probable prolonged grief disorder (PGD). Multilevel analysis showed significantly higher level of PG among those who reported high exposure to the media coverage (>4 hours daily) the first month after the attack, among females, and among those who were in contact with their son/daughter/brother/sister by telephone during the attack. With the cross-sectional design, caution should be taken about making interpretations about causal effects. Media exposure may trigger or maintain prolonged grief reactions. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Cultural Adaptations of Prolonged Exposure Therapy for Treatment and Prevention of Posttraumatic Stress Disorder in African Americans

PubMed Central

Williams, Monnica T.; Malcoun, Emily; Sawyer, Broderick A.; Davis, Darlene M.; Bahojb Nouri, Leyla; Bruce, Simone Leavell

2014-01-01

Posttraumatic stress disorder (PTSD) is a highly disabling disorder, afflicting African Americans at disproportionately higher rates than the general population. When receiving treatment, African Americans may feel differently towards a European American clinician due to cultural mistrust. Furthermore, racism and discrimination experienced before or during the traumatic event may compound posttrauma reactions, impacting the severity of symptoms. Failure to adapt treatment approaches to encompass cultural differences and racism-related traumas may decrease treatment success for African American clients. Cognitive behavioral treatment approaches are highly effective, and Prolonged Exposure (PE) in particular has the most empirical support for the treatment of PTSD. This article discusses culturally-informed adaptations of PE that incorporates race-related trauma themes specific to the Black experience. These include adding more sessions at the front end to better establish rapport, asking directly about race-related themes during the assessment process, and deliberately bringing to the forefront race-related experiences and discrimination during treatment when indicated. Guidelines for assessment and the development of appropriate exposures are provided. Case examples are presented demonstrating adaptation of PE for a survivor of race-related trauma and for a woman who developed internalized racism following a sexual assault. Both individuals experienced improvement in their posttrauma reactions using culturally-informed adaptations to PE. PMID:25379272

Effects of prolonged exposure to space flight factors for 175 days on lettuce seeds

NASA Astrophysics Data System (ADS)

Nevzgodina, L. V.; Maximova, E. N.; Akatov, Yu. A.

We have studied the effects of prolonged (up to 175 days) exposure of Lactuca sativa seeds to space flight factors, including primary cosmic radiation heavy ions. The data obtained evidence a significant fourfold increase ofs pontaneous mutagenesis in seeds both with regard to the total number of aberrant cells as well as the formation of single cells with multiple aberrations. Comparison of the present experiment with earlier works shows that the frequency of such aberrations increases with the duration of the flight.

Determining a threshold sub-acute dose leading to minimal physiological alterations following prolonged exposure to the nerve agent VX in rats.

PubMed

Bloch-Shilderman, E; Rabinovitz, I; Egoz, I; Yacov, G; Allon, N; Nili, U

2018-02-01

VX, a potent inhibitor of cholinesterase (ChE), is considered as one of the most toxic, persistent and least volatile nerve agents. VX is absorbed in various environmental surfaces and is gradually released long after its initial dispersal. Its toxicity is mainly caused by disrupting central and peripheral cholinergic nervous system activity, leading to potential long-term detrimental effects on health. The primary objective of the present study was to assess the threshold VX dose leading to minimal physiological alterations following prolonged VX exposure. Characterization of such a threshold is crucial for dealing with unresolved operative dilemmas such as when it is safe enough to resettle a population that has been evacuated from a VX-contaminated area. Rats, continuously exposed to various doses of VX (0.225-45 µg/kg/day) for 4 weeks via implanted mini-osmotic pumps, showed a dose-dependent and continuous decrease in ChE activity in whole blood, brain and muscles, ranging between 20 and 100%. Exposure to 13.5 µg/kg/day led to a stable low ChE activity level (~ 20%), accompanied by transient and negligible electrocorticogram spectral power transformations, especially in the theta and alpha brain wave frequencies, and a significant decrease in total brain M2 receptor density. These changes were neither accompanied by observable signs of intoxication nor by changes in motor function, circadian rhythm or TSPO level (a reliable marker of brain damage). Following exposure to lower doses of 2.25 and 0.225 µg/kg/day, the only change measured was a reduction in ChE activity of 60 and 20%, respectively. Based on these results, we delineate ChE inhibition as the physiological measure most susceptible to alterations following prolonged VX exposure, and determine for the first time the threshold sub-acute VX dose for minimal physiological effects (up to 20% reduction in ChE activity) in the rat as 0.225 µg/kg/day.

POPULATION-BASED EXPOSURE MODELING FOR AIR POLLUTANTS AT EPA'S NATIONAL EXPOSURE RESEARCH LABORATORY

EPA Science Inventory

The US EPA's National Exposure Research Laboratory (NERL) has been developing, applying, and evaluating population-based exposure models to improve our understanding of the variability in personal exposure to air pollutants. Estimates of population variability are needed for E...

Combining group-based exposure therapy with prolonged exposure to treat U.S. Vietnam veterans with PTSD: a case study.

PubMed

Ready, David J; Vega, Edward M; Worley, Virginia; Bradley, Bekh

2012-10-01

Group-based exposure therapy (GBET) of 16-week duration was developed to treat combat-related posttraumatic stress disorder (PTSD) and decreased PTSD symptoms in 3 noncontrolled open trials with low attrition (0%-5%). Group-based exposure therapy has not produced as much PTSD symptom reduction as Prolonged Exposure (PE) within a U.S. Veterans Affairs PTSD treatment program, although PE had more dropouts (20%). This pilot study was of a model that combined key elements of GBET with components of PE in an effort to increase the effectiveness of a group-based treatment while reducing its length and maintaining low attrition. Twice per week, 8 Vietnam combat veterans with PTSD were treated for 12 weeks, with an intervention that included 2 within-group war trauma presentations per participant, 6 PE style individual imaginal exposure (IE) sessions per participant, daily listening to recorded IE sessions, and daily in vivo exposure exercises. All completed treatment and showed Significant reductions on all measures of PTSD with large effect sizes; 7 participants no longer met PTSD criteria on treating clinician administered interviews and a self-report measure at posttreatment. Significant reductions in depression with large effect sizes and moderate reductions in PTSD-related cognitions were also found. Most gains were maintained 6 months posttreatment. Published 2012. This article is a US Government work and is in the public domain in the USA.

Emotional attentional control predicts changes in diurnal cortisol secretion following exposure to a prolonged psychosocial stressor.

PubMed

Lenaert, Bert; Barry, Tom J; Schruers, Koen; Vervliet, Bram; Hermans, Dirk

2016-01-01

Hypothalamic-pituitary-adrenal (HPA) axis irregularities have been associated with several psychological disorders. Hence, the identification of individual difference variables that predict variations in HPA-axis activity represents an important challenge for psychiatric research. We investigated whether self-reported attentional control in emotionally demanding situations prospectively predicted changes in diurnal salivary cortisol secretion following exposure to a prolonged psychosocial stressor. Low ability to voluntarily control attention has previously been associated with anxiety and depressive symptomatology. Attentional control was assessed using the Emotional Attentional Control Scale. In students who were preparing for academic examination, salivary cortisol was assessed before (time 1) and after (time 2) examination. Results showed that lower levels of self-reported emotional attentional control at time 1 (N=90) predicted higher absolute diurnal cortisol secretion and a slower decline in cortisol throughout the day at time 2 (N=71). Difficulty controlling attention during emotional experiences may lead to chronic HPA-axis hyperactivity after prolonged exposure to stress. These results indicate that screening for individual differences may foster prediction of HPA-axis disturbances, paving the way for targeted disorder prevention. Copyright © 2015 Elsevier Ltd. All rights reserved.

Music exposure induced prolongation of cardiac allograft survival and generated regulatory CD4⁺ cells in mice.

PubMed

Uchiyama, M; Jin, X; Zhang, Q; Amano, A; Watanabe, T; Niimi, M

2012-05-01

In clinical practice, music has been used to decrease stress, heart rate, and blood pressure and to provide a distraction from disease symptoms. We investigated sound effects on alloimmune responses in murine heart transplantation. Naïve and eardrum-ruptured CBA/N (CBA, H2(K)) underwent transplantation of a C57BL/6 (B6, H2(b)) heart and were exposed to 1 of 3 types of music-opera (La Traviata), classical (Mozart), and New Age (Enya)-or 1 of 6 different single sound frequencies for 7 days. An adoptive transfer study was performed to determine whether regulatory cells were generated in allograft recipients. Cell-proliferation, cytokine, and flow cytometry assessments were also performed. CBA recipients of a B6 graft exposed to opera and classical music had significantly prolonged allograft survival (median survival times [MSTs], 26.5 and 20 days, respectively), whereas those exposed to 6 single sound frequencies and New Age did not (MSTs, 7, 8, 9, 8, 8, 8, and 11 days, respectively). Untreated and eardrum-ruptured CBA rejected B6 grafts acutely (MSTs, 7 and 8.5 days, respectively). Adoptive transfer of whole splenocytes, CD4(+) cells, and CD4(+)CD25(+) cells from opera-exposed primary recipients resulted in significantly prolonged allograft survival in naive secondary recipients (MSTs, 36, 68, and >50 days, respectively). Cell-proliferation, interleukin (IL)-2 and interferon-γ were suppressed in opera-exposed mice, whereas IL-4 and IL-10 from opera-exposed recipients were up-regulated. Flow cytometry studies showed an increased CD4(+)CD25(+)Foxp3(+) cell population in splenocytes from opera-exposed mice. In conclusion, exposure to some types of music may induce prolonged survival of fully allogeneic cardiac allografts and generate CD4(+)CD25(+)Foxp3(+) regulatory cells. Copyright © 2012 Elsevier Inc. All rights reserved.

Pankiller effect of prolonged exposure to menadione on glioma cells: potentiation by vitamin C.

PubMed

Vita, Marina F; Nagachar, Nivedita; Avramidis, Dimitrios; Delwar, Zahid M; Cruz, Mabel H; Siden, Åke; Paulsson, Kajsa M; Yakisich, Juan Sebastian

2011-12-01

Menadione (Vitamin K3) has anti-tumoral effects against a wide range of cancer cells. Its potential toxicity to normal cells and narrow therapeutic range limit its use as single agent but in combination with radiation or other anti-neoplastic agents can be of therapeutic use. In this paper, we first evaluated the early (within 3 h) effect of menadione on ongoing DNA replication. In normal rat cerebral cortex mini-units menadione showed an age dependent anti-proliferative effect. In tissue mini-units prepared from newborn rats, menadione inhibited ongoing DNA replication with an IC (50) of approximately 10 μM but 50 μM had no effect on mini-units from prepared adult rat tissue. The effect of short (72 h) and prolonged exposure (1-2 weeks) to menadione alone in the DBTRG.05MG human glioma cells line and in combination with vitamin C was studied. After short period of exposure data show that menadione alone or in combination with vitamin C provided similar concentration-response curves (and IC(50) values). Prolonged exposure to these drugs was evaluated by their ability to kill 100% of glioma cells and prevent regrowth when cells are re-incubated in drug-free media. In this long-term assay, menadione:vitamin C at a ratio 1:100 showed higher anti-proliferative activity when compared to each drug alone and allowed to reduce each drug concentration between 2.5 to 5-fold. Similar anti-proliferative effect was demonstrated in 8 patient derived glioblastoma cell cultures. Our data should be able to encourage further advanced studies on animal models to evaluate the potential use of this combination therapy for glioma treatment.

Pesticide exposures and respiratory health in general populations.

PubMed

Ye, Ming; Beach, Jeremy; Martin, Jonathan W; Senthilselvan, Ambikaipakan

2017-01-01

Human exposures to pesticides can occur in the workplace, in the household and through the ambient environment. While several articles have reviewed the impact of pesticide exposures on human respiratory health in occupational settings, to the best of our knowledge, this article is the first one to review published studies on the association between pesticide exposures and human respiratory health in the general populations. In this article, we critically reviewed evidences up to date studying the associations between non-occupational pesticide exposures and respiratory health in general populations. This article also highlighted questions arising from these studies, including our recent analyses using the data from the Canadian Health Measures Survey (CHMS), for future research. We found few studies have addressed the impact of environmental pesticide exposures on respiratory health, especially on lung function, in general populations. In the studies using the data from CHMS Cycle 1, exposures to OP insecticides, pyrethroid insecticides, and the organochlorine pesticide DDT were associated with impaired lung function in the Canadian general population, but no significant associations were observed for the herbicide 2,4-D. Future research should focus on the potential age-specific and pesticide-specific effect on respiratory health in the general population, and repeated longitudinal study design is critical for assessing the temporal variations in pesticide exposures. Research findings from current studies of non-occupational pesticide exposures and their health impact in general population will help to improve the role of regulatory policies in mitigating pesticide-related public health problems, and thereafter providing greater benefit to the general population. Copyright © 2016. Published by Elsevier B.V.

Clinician perceptions of using a smartphone app with prolonged exposure therapy.

PubMed

Kuhn, Eric; Eftekhari, Afsoon; Hoffman, Julia E; Crowley, Jill J; Ramsey, Kelly M; Reger, Greg M; Ruzek, Josef I

2014-11-01

Clinician perceptions of clinical innovations affect their adoption and spread. This study investigated mental health clinicians' (n = 163) perceptions of a patient-facing smartphone application (app) for prolonged exposure (PE) therapy for posttraumatic stress disorder, before its public release. After reading a description of the app, participants rated perceptions of it based on diffusion of innovations theory constructs. Perceptions were generally favorable regarding the app's relative advantage over existing PE practices, compatibility with their values and needs, and complexity. Age (<40 years), smartphone ownership, and having used apps in care related to more favorable perceptions. Smartphone ownership, relative advantage, and complexity significantly predicted intention to use the app if it were available. These findings suggest that clinicians are receptive to using a PE app and that dissemination efforts should target sub-groups of PE clinicians to maximize adoption.

The effect of prolonged exposure to 750 C air on the tribological performance of PM212

NASA Technical Reports Server (NTRS)

Bemis, Kirk; Bogdanski, Michael S.; Dellacorte, Christopher; Sliney, Harold E.

1994-01-01

The effect of prolonged exposure to 750 C air on the tribological performance and dimensional stability of PM212, a high temperature, self-lubricating composite, is studied. PM212, by weight, contains 70 percent metal-bonded Cr3C2, 15 percent BaF2/CaF2 eutectic, and 15 percent silver. Rub blocks were fabricated from PM212 by cold isostatic pressing followed by sintering. Prior to tribo-testing, the rub blocks were exposed to 750 C air for periods ranging from 100 to 1000 hours. Then, the rub blocks were slid against nickel-based superalloy disks in a double-rub-block tribometer in air under a 66 N load at temperatures from 25 to 750 C with a sliding velocity of 0.36 m/s. Unexposed rub blocks were tested for baseline comparison. Friction coefficients ranged from 0.24 to 0.37 for the unexposed rub blocks and from 0.32 to 0.56 for the exposed ones. Wear for both the composite blocks and superalloy disks was typically in the moderate to low range of 10(exp -5) to 10(exp -6) mm(exp 3)/N-m. Friction and wear data were similar for the rub blocks exposed for 100, 500, and 1000 hours. Prolonged exposure to 750 C air increased friction and wear of the PM212 rub blocks at room temperature, but their triboperformance remained unaffected at higher temperatures, probably due to the formation of lubricious metal oxides. Dimensional stability of the composite was studied by exposing specimens of varying thicknesses for 500 hours in air at 750 C. Block thicknesses were found to increase with increased exposure time until steady state was reached after 100 hours of exposure, probably due to oxidation.

Acceptability of prolonged exposure therapy among U.S. Iraq war veterans with PTSD symptomology.

PubMed

Kehle-Forbes, Shannon M; Polusny, Melissa A; Erbes, Christopher R; Gerould, Heather

2014-08-01

Despite efforts to increase the availability of prolonged exposure therapy (PE) within the Department of Veterans Affairs, little is known about the acceptability of PE among veteran populations. We queried a sample of 58 U.S. National Guard Iraq War veterans previously deployed to combat who screened positive for posttraumatic stress disorder (PTSD) as to whether they would prefer PE, treatment with an antidepressant, or no treatment. We also gathered open-ended responses regarding the veterans' reasons for their choice and potential barriers to engaging in that treatment. A majority (53.4%) of veterans who completed the interview said they would choose to participate in PE, 36.2% preferred antidepressant treatment, 8.6% chose no treatment, and 1.8% were unable to choose among the options. Credibility of the treatment rationale and beliefs about the treatment's efficacy were the most frequently given reasons for choosing PE (45.2%); past treatment experience was the most common reason for choosing antidepressant treatment (47.6%). The most commonly cited barrier for those who chose both antidepressant treatment and PE was time to participate (52.4% and 77.4%, respectively). The findings suggest that PE is a credible and acceptable treatment option for veterans with PTSD symptomology. Published 2014. This article is a US Government work and is in the public domain in the USA.

Effects of prolonged light exposure times on water sorption, solubility and cross-linking density of simplified etch-and-rinse adhesives.

PubMed

Wambier, Letícia; Malaquias, Tamirez; Wambier, Denise Stadler; Patzlaff, Rafael T; Bauer, José; Loguercio, Alessandro D; Reis, Alessandra

2014-06-01

This study evaluated the effects of light exposure times on water sorption, solubility, and polymer cross-linking density of simplified etch-and-rinse adhesives. Four commercial adhesives (XP Bond, Adper Single Bond 2, Tetric N-Bond, and Ambar) were selected, and resin disks 5 mm in diameter and 1.0 mm thick were prepared and light cured for 20, 40, or 80 s using an LED light-curing unit at 1200 mW/cm2. Water sorption and solubility were evaluated over a 28-day period. For polymer cross-linking density, additional specimens were prepared and their Knoop hardness measured before and after immersion in 100% ethanol. The data from each test were evaluated using a two-way ANOVA and Tukey's test (α = 0.05). The XP Bond adhesive showed higher water sorption (similar to Adper Single Bond 2) and solubility (p < 0.05) than did the other materials. Prolonged exposure times did not reduce the water sorption but did reduce the solubility of all tested materials (p < 0.05). For Ambar, the increase in the exposure time resulted in a significantly lower percent reduction in hardness. Water sorption, solubility, and cross-linking density of the materials selected in this study seem to be mainly influenced by the adhesive composition. Prolonged light exposure times reduced the solubility of the materials.

Prolonged intrahepatic cholestasis after exposure to loxoprofen.

PubMed

Ichikawa, Takeshi; Sato, Hiroko; Kaira, Kyoichi; Oh-I, Shinsuke; Kakizaki, Satoru; Sato, Ken; Takagi, Hitoshi; Mori, Masatomo

2008-12-01

The objective of this report was to describe a case of prolonged intrahepatic cholestasis likely associated with the use of loxoprofen, a phenylpropionate NSAID. A 36-year-old female patient was transferred to Gunma University Hospital, Maebashi, Japan, with progressive pruritus and jaundice that developed after 5-day treatment with 120 mg/d of loxoprofen (maximum recommended dose, 180 mg/d) for menstrual pain. Liver function tests found the following concentrations: total bilirubin, 27.5 mg/dL (normal [nl] range, 0.3-1.2 mg/dL); aspartate aminotransferase, 151 IU/L (nl, 13-33 IU/L); alkaine aminotransferase, 470 IU/L (nl, 8-42 IU/L); alkaline phosphatase, 1082 IU/L (n1, 115-359 IUAL); and gamma-glutamyl transpeptidase, 795 IU/L (nl, 10-47 IU/L) indicative of intrahepatic cholestasis. No use of alcohol or other drugs or herbal products was reported. The patient had a history of elevated hepatic enzymes of unknown origin following the use of mefenamic acid. The patient was prescribed ursodeoxycholic acid 3 weeks after the onset of symptoms of intrahepatic cholestasis. Thereafter, due to progressive cholestasis, an IV pulse of methylprednisolone (1000 mg/d) and the herbal product Inchin-ko-to (TJ-135) were administered. Plasma bilirubin adsorption (PA) and plasma exchange (PE) were performed. Following treatment with PA and PE for 3 weeks with administration of methylprednisolone and Inchin-ko-to, signs and symptoms of intrahepatic cholestasis began to resolve (3.5 months after the onset); they were completely resolved 8 months after the initial episode. A Naranjo scale score of 6 suggested that loxoprofen was likely the cause of the prolonged cholestasis in this patient. Based on the Naranjo score, this case of prolonged intrahepatic cholestasis in a young woman was likely associated with loxoprofen use.

PM POPULATION EXPOSURE AND DOSE MODELS

EPA Science Inventory

The overall objective of this study is the development of a refined probabilistic exposure and dose model for particulate matter (PM) suitable for predicting PM10 and PM2.5 population exposures. This modeling research will be conducted both in-house by EPA scientists and through...

Improving PTSD Outcomes in OIF/OEF Returnees: A Randomized Clinical Trial of Hydrocortisone Augmentation of Prolonged Exposure Therapy

DTIC Science & Technology

2012-08-01

Melissa D . Altman, PhD will ensure that the ratings are accomplished in a reasonable time frame, and make the results available to the PI and co...Glucocorticoid augmentation of prolonged exposure therapy: rationale and case report. European Journal of Traumatology. 2010(1): 5643. d . Solutions to...Brief Assessment of Cognition in Schizophrenia (BACS): Symbol-Coding Category Fluency: Animal Naming Trail Making Test: Part A Timed paper

Unusual Versatility of the Filamentous, Diazotrophic Cyanobacterium Anabaena torulosa Revealed for Its Survival during Prolonged Uranium Exposure

PubMed Central

Chandwadkar, Pallavi; Nayak, Chandrani

2017-01-01

ABSTRACT Reports on interactions between cyanobacteria and uranyl carbonate are rare. Here, we present an interesting succession of the metabolic responses employed by a marine, filamentous, diazotrophic cyanobacterium, Anabaena torulosa for its survival following prolonged exposure to uranyl carbonate extending up to 384 h at pH 7.8 under phosphate-limited conditions. The cells sequestered uranium (U) within polyphosphates on initial exposure to 100 μM uranyl carbonate for 24 to 28 h. Further incubation until 120 h resulted in (i) significant degradation of cellular polyphosphates causing extensive chlorosis and cell lysis, (ii) akinete differentiation followed by (iii) extracellular uranyl precipitation. X-ray diffraction (XRD) analysis, fluorescence spectroscopy, X-ray absorption near edge structure (XANES), and extended X-ray absorption fine structure (EXAFS) spectroscopy established the identity of the bioprecipitated uranium as a U(VI) autunite-type mineral, which settled at the bottom of the vessel. Surprisingly, A. torulosa cells resurfaced as small green flakes typical of actively growing colonies on top of the test solutions within 192 to 240 h of U exposure. A consolidated investigation using kinetics, microscopy, and physiological and biochemical analyses suggested a role of inducible alkaline phosphatase activity of cell aggregates/akinetes in facilitating the germination of akinetes leading to substantial regeneration of A. torulosa by 384 h of uranyl incubation. The biomineralized uranium appeared to be stable following cell regeneration. Altogether, our results reveal novel insights into the survival mechanism adopted by A. torulosa to resist sustained uranium toxicity under phosphate-limited oxic conditions. IMPORTANCE Long-term effects of uranyl exposure in cyanobacteria under oxic phosphate-limited conditions have been inadequately explored. We conducted a comprehensive examination of the metabolic responses displayed by a marine cyanobacterium

Unusual Versatility of the Filamentous, Diazotrophic Cyanobacterium Anabaena torulosa Revealed for Its Survival during Prolonged Uranium Exposure.

PubMed

Acharya, Celin; Chandwadkar, Pallavi; Nayak, Chandrani

2017-05-01

Reports on interactions between cyanobacteria and uranyl carbonate are rare. Here, we present an interesting succession of the metabolic responses employed by a marine, filamentous, diazotrophic cyanobacterium, Anabaena torulosa for its survival following prolonged exposure to uranyl carbonate extending up to 384 h at pH 7.8 under phosphate-limited conditions. The cells sequestered uranium (U) within polyphosphates on initial exposure to 100 μM uranyl carbonate for 24 to 28 h. Further incubation until 120 h resulted in (i) significant degradation of cellular polyphosphates causing extensive chlorosis and cell lysis, (ii) akinete differentiation followed by (iii) extracellular uranyl precipitation. X-ray diffraction (XRD) analysis, fluorescence spectroscopy, X-ray absorption near edge structure (XANES), and extended X-ray absorption fine structure (EXAFS) spectroscopy established the identity of the bioprecipitated uranium as a U(VI) autunite-type mineral, which settled at the bottom of the vessel. Surprisingly, A. torulosa cells resurfaced as small green flakes typical of actively growing colonies on top of the test solutions within 192 to 240 h of U exposure. A consolidated investigation using kinetics, microscopy, and physiological and biochemical analyses suggested a role of inducible alkaline phosphatase activity of cell aggregates/akinetes in facilitating the germination of akinetes leading to substantial regeneration of A. torulosa by 384 h of uranyl incubation. The biomineralized uranium appeared to be stable following cell regeneration. Altogether, our results reveal novel insights into the survival mechanism adopted by A. torulosa to resist sustained uranium toxicity under phosphate-limited oxic conditions. IMPORTANCE Long-term effects of uranyl exposure in cyanobacteria under oxic phosphate-limited conditions have been inadequately explored. We conducted a comprehensive examination of the metabolic responses displayed by a marine cyanobacterium, Anabaena

European consumer exposure to cosmetic products, a framework for conducting population exposure assessments.

PubMed

Hall, B; Tozer, S; Safford, B; Coroama, M; Steiling, W; Leneveu-Duchemin, M C; McNamara, C; Gibney, M

2007-11-01

Access to reliable exposure data is essential to evaluate the toxicological safety of ingredients in cosmetic products. This study was carried out by European cosmetic manufacturers acting within the trade association Colipa, with the aim to construct a probabilistic European population model of exposure. The study updates, in distribution form, the current exposure data on daily quantities of six cosmetic products. Data were collected using a combination of market information databases and a controlled product use study. In total 44,100 households and 18,057 individual consumers in five European countries provided data using their own products. All product use occasions were recorded, including those outside of home. The raw data were analysed using Monte Carlo simulation and a European Statistical Population Model of exposure was constructed. A significant finding was an inverse correlation between frequency of product use and quantity used per application for body lotion, facial moisturiser, toothpaste and shampoo. Thus it is not appropriate to calculate daily exposure to these products by multiplying the maximum frequency value by the maximum quantity per event value. The results largely confirm the exposure parameters currently used by the cosmetic industry. Design of this study could serve as a model for future assessments of population exposure to chemicals in products other than cosmetics.

Randomized Trial of Prolonged Exposure for Posttraumatic Stress Disorder with and without Cognitive Restructuring: Outcome at Academic and Community Clinics

ERIC Educational Resources Information Center

Foa, Edna B.; Hembree, Elizabeth A.; Cahill, Shawn P.; Rauch, Sheila A. M.; Riggs, David S.; Feeny, Norah C.; Yadin, Elna

2005-01-01

Female assault survivors (N = 171) with chronic posttraumatic stress disorder (PTSD) were randomly assigned to prolonged exposure (PE) alone, PE plus cognitive restructuring (PE/CR), or wait-list (WL). Treatment, which consisted of 9-12 sessions, was conducted at an academic treatment center or at a community clinic for rape survivors. Evaluations…

In Vitro Acquisition of Secondary Azole Resistance in Aspergillus fumigatus Isolates after Prolonged Exposure to Itraconazole: Presence of Heteroresistant Populations

PubMed Central

Escribano, Pilar; Recio, Sandra; Peláez, Teresa; González-Rivera, Milagros; Bouza, Emilio

2012-01-01

Secondary resistance to azoles in Aspergillus fumigatus isolates from patients taking long-term itraconazole therapy has been described. We studied the acquisition of secondary azole resistance in 20 A. fumigatus isolates with no mutations at codon 54, 98, 138, 220, 432, or 448 in the cyp51A gene. Adjusted conidium inocula (3 × 107 CFU/ml) of each isolate were prepared and progressively or directly exposed to increasing itraconazole concentrations, ranging from 0.5 μg/ml to 16 μg/ml. Itraconazole, voriconazole, and posaconazole MICs were determined using the CLSI M38-A2 procedure before (MICinitial) and after (MICfinal) exposure to itraconazole. In both procedures, the MICfinal was significantly higher than the MICinitial. However, after progressive exposure to itraconazole, the MICs of the three azoles were higher than after direct exposure. No mutations were found at codon 54, 98, 138, 220, 432, or 448 in the cyp51A gene of isolates growing at the highest concentration of itraconazole. More concentrated conidium inocula (2 × 109 CFU/ml) plated in itraconazole at 4 μg/ml revealed the presence of heteroresistant populations in two initially wild-type isolates. These isolates became resistant to itraconazole and posaconazole only after use of the concentrated inoculum. These heteroresistant isolates harbored a mutation at codon G54, and the MICs of itraconazole and posaconazole were >16 μg/ml. In all procedures, A. fumigatus short tandem repeat (STRAf) typing was used to demonstrate that the genotype did not change before or after exposure to itraconazole. PMID:22006000

Ecological modelling and toxicity data coupled to assess population recovery of marine amphipod Gammarus locusta: Application to disturbance by chronic exposure to aniline.

PubMed

de los Santos, Carmen B; Neuparth, Teresa; Torres, Tiago; Martins, Irene; Cunha, Isabel; Sheahan, Dave; McGowan, Tom; Santos, Miguel M

2015-06-01

A population agent-based model of marine amphipod Gammarus locusta was designed and implemented as a basis for ecological risk assessment of chemical pollutants impairing life-history traits at the individual level. We further used the model to assess the toxic effects of aniline (a priority hazardous and noxious substance, HNS) on amphipod populations using empirically-built dose-response functions derived from a chronic bioassay that we previously performed with this species. We observed a significant toxicant-induced mortality and adverse effects in reproductive performance (reduction of newborn production) in G. locusta at the individual level. Coupling the population model with the toxicological data from the chronic bioassay allowed the projection of the ecological costs associated with exposure to aniline that might occur in wild populations. Model simulations with different scenarios indicated that even low level prolonged exposure to the HNS aniline can have significant long-term impacts on G. locusta population abundance, until the impacted population returns to undisturbed levels. This approach may be a useful complement in ecotoxicological studies of chemical pollution to transfer individual-collected data to ecological-relevant levels. Copyright © 2015 Elsevier B.V. All rights reserved.

Effects of processing and prolonged high temperature exposure on the microstructure of Nb-1Zr-C sheet

NASA Technical Reports Server (NTRS)

Uz, Mehmet; Titran, R. H.

1993-01-01

High temperature stability of the microstructure of Nb-1Zr sheet containing 0.1 and 0.06 wt. percent C was studied as affected by processing and prolonged 1350 K exposure with and without applied stress. Sheets were fabricated by cold rolling bars that were single-, double-, or triple-extruded at 1900 K. Creep samples were double-annealed (1 h at 1755 K + 2 h at 1475 K) prior to testing at 1350 K and 10,000 - 34,500 h. The microstructures of the as-cast, extruded, rolled, DA, and crept samples were characterized using various metallographic and analytical methods. The precipitates were rather coarse Nb2C initially, but transformed to finer (less than or equal to 1 micron) carbides of (Zr, Nb)C with each subsequent high temperature process. The grain size, and the relative amount and morphology of (Zr, Nb)C were found to be affected by the number of extrusions and to some extent by C-content. However, the microstructures of all the crept samples were similar with (Zr, Nb)C distributed throughout the matrix indicating that prolonged exposure to 1350 K gave rise to complete transformation of Nb2C to (Zr, Nb)C regardless of the processing history. These and other observations are presented with the emphasis on the correlation between processing, microstructure, and creep properties.

Integrating population dynamics into mapping human exposure to seismic hazard

NASA Astrophysics Data System (ADS)

Freire, S.; Aubrecht, C.

2012-11-01

Disaster risk is not fully characterized without taking into account vulnerability and population exposure. Assessment of earthquake risk in urban areas would benefit from considering the variation of population distribution at more detailed spatial and temporal scales, and from a more explicit integration of this improved demographic data with existing seismic hazard maps. In the present work, "intelligent" dasymetric mapping is used to model population dynamics at high spatial resolution in order to benefit the analysis of spatio-temporal exposure to earthquake hazard in a metropolitan area. These night- and daytime-specific population densities are then classified and combined with seismic intensity levels to derive new spatially-explicit four-class-composite maps of human exposure. The presented approach enables a more thorough assessment of population exposure to earthquake hazard. Results show that there are significantly more people potentially at risk in the daytime period, demonstrating the shifting nature of population exposure in the daily cycle and the need to move beyond conventional residence-based demographic data sources to improve risk analyses. The proposed fine-scale maps of human exposure to seismic intensity are mainly aimed at benefiting visualization and communication of earthquake risk, but can be valuable in all phases of the disaster management process where knowledge of population densities is relevant for decision-making.

Rates and risk factors for prolonged opioid use after major surgery: population based cohort study

PubMed Central

Soneji, Neilesh; Ko, Dennis T; Yun, Lingsong; Wijeysundera, Duminda N

2014-01-01

Objective To describe rates and risk factors for prolonged postoperative use of opioids in patients who had not previously used opioids and undergoing major elective surgery. Design Population based retrospective cohort study. Setting Acute care hospitals in Ontario, Canada, between 1 April 2003 and 31 March 2010. Participants 39 140 opioid naïve patients aged 66 years or older who had major elective surgery, including cardiac, intrathoracic, intra-abdominal, and pelvic procedures. Main outcome measure Prolonged opioid use after discharge, as defined by ongoing outpatient prescriptions for opioids for more than 90 days after surgery. Results Of the 39 140 patients in the entire cohort, 49.2% (n=19 256) were discharged from hospital with an opioid prescription, and 3.1% (n=1229) continued to receive opioids for more than 90 days after surgery. Following risk adjustment with multivariable logistic regression modelling, patient related factors associated with significantly higher risks of prolonged opioid use included younger age, lower household income, specific comorbidities (diabetes, heart failure, pulmonary disease), and use of specific drugs preoperatively (benzodiazepines, selective serotonin reuptake inhibitors, angiotensin converting enzyme inhibitors). The type of surgical procedure was also highly associated with prolonged opioid use. Compared with open radical prostatectomies, both open and minimally invasive thoracic procedures were associated with significantly higher risks (odds ratio 2.58, 95% confidence interval 2.03 to 3.28 and 1.95 1.36 to 2.78, respectively). Conversely, open and minimally invasive major gynaecological procedures were associated with significantly lower risks (0.73, 0.55 to 0.98 and 0.45, 0.33 to 0.62, respectively). Conclusions Approximately 3% of previously opioid naïve patients continued to use opioids for more than 90 days after major elective surgery. Specific patient and surgical characteristics were associated with

Prolonged exposure to arsenic in UK private water supplies: toenail, hair and drinking water concentrations.

PubMed

Middleton, D R S; Watts, M J; Hamilton, E M; Fletcher, T; Leonardi, G S; Close, R M; Exley, K S; Crabbe, H; Polya, D A

2016-05-18

Chronic exposure to arsenic (As) in drinking water is an established cause of cancer and other adverse health effects. Arsenic concentrations >10 μg L(-1) were previously measured in 5% of private water supplies (PWS) in Cornwall, UK. The present study investigated prolongued exposure to As by measuring biomarkers in hair and toenail samples from 212 volunteers and repeated measurements of As in drinking water from 127 households served by PWS. Strong positive Pearson correlations (rp = 0.95) indicated stability of water As concentrations over the time period investigated (up to 31 months). Drinking water As concentrations were positively correlated with toenail (rp = 0.53) and hair (rp = 0.38) As concentrations - indicative of prolonged exposure. Analysis of washing procedure solutions provided strong evidence of the effective removal of exogenous As from toenail samples. Significantly higher As concentrations were measured in hair samples from males and smokers and As concentrations in toenails were negatively associated with age. A positive association between seafood consumption and toenail As and a negative association between home-grown vegetable consumption and hair As was observed for volunteers exposed to <1 As μg L(-1) in drinking water. These findings have important implications regarding the interpretation of toenail and hair biomarkers. Substantial variation in biomarker As concentrations remained unaccounted for, with soil and dust exposure as possible explanations.

An estimation of Canadian population exposure to cosmic rays.

PubMed

Chen, Jing; Timmins, Rachel; Verdecchia, Kyle; Sato, Tatsuhiko

2009-08-01

The worldwide average exposure to cosmic rays contributes to about 16% of the annual effective dose from natural radiation sources. At ground level, doses from cosmic ray exposure depend strongly on altitude, and weakly on geographical location and solar activity. With the analytical model PARMA developed by the Japan Atomic Energy Agency, annual effective doses due to cosmic ray exposure at ground level were calculated for more than 1,500 communities across Canada which cover more than 85% of the Canadian population. The annual effective doses from cosmic ray exposure in the year 2000 during solar maximum ranged from 0.27 to 0.72 mSv with the population-weighted national average of 0.30 mSv. For the year 2006 during solar minimum, the doses varied between 0.30 and 0.84 mSv, and the population-weighted national average was 0.33 mSv. Averaged over solar activity, the Canadian population-weighted average annual effective dose due to cosmic ray exposure at ground level is estimated to be 0.31 mSv.

Factors related to clinician attitudes toward prolonged exposure therapy for PTSD.

PubMed

Ruzek, Josef I; Eftekhari, Afsoon; Rosen, Craig S; Crowley, Jill J; Kuhn, Eric; Foa, Edna B; Hembree, Elizabeth A; Karlin, Bradley E

2014-08-01

This study examines pretraining attitudes toward prolonged exposure (PE) therapy in a sample of 1,275 mental health clinicians enrolled in a national PE training program sponsored by the U.S. Department of Veterans Affairs. Attitudes assessed via survey included values placed on outcomes targeted by PE, outcome expectancies (positive expectancies for patient improvement and negative expectancies related to patient deterioration, clinician time burden, and clinician emotional burden), and self-efficacy for delivering PE. Results indicated that clinicians were receptive to learning PE and had positive expectations about the treatment, but expressed concerns that PE might increase patient distress. Responses varied by clinician characteristics with psychologists, clinicians working in specialty PTSD treatment settings (as opposed to those in mental health clinics and other clinic types), and those with a primarily cognitive-behavioral orientation expressing attitudes that were most supportive of learning and implementing PE across various indicators. Implications for addressing attitudinal barriers to implementation of PE therapy are discussed. Published 2014. This article is a US Government work and is in the public domain in the USA.

Outcomes of Prolonged Exposure therapy for veterans with posttraumatic stress disorder.

PubMed

Goodson, Jason T; Lefkowitz, Carin M; Helstrom, Amy W; Gawrysiak, Michael J

2013-08-01

Prolonged Exposure (PE) is an evidenced-based psychotherapy for posttraumatic stress disorder (PTSD) that is being disseminated nationally within the U.S. Department of Veterans Affairs (VA) with promising initial results. Empirical evidence, however, regarding the effectiveness of PE for treatment of PTSD in military veterans is limited. Building on previous treatment outcome research, the current study investigated the effectiveness of PE in a diverse veteran sample. One-hundred fifteen veterans were enrolled in PE at an urban VA medical center and its surrounding outpatient clinics. PTSD and depression symptoms as well as quality of life were measured before and after treatment. Several baseline patient characteristics were examined as predictors of treatment response. Eighty-four participants completed treatment. Participants experienced a 42% reduction in PTSD symptoms, a 31% reduction in depression symptoms, and an increase in quality of life following PE. Veterans not prescribed psychotropic medication reported greater PTSD symptom reduction than veterans prescribed such medication. The implications of these results for treatment programs targeting PTSD in veterans are discussed. Copyright © 2013 International Society for Traumatic Stress Studies.

Modeling Population and Ecosystem Response to Sublethal Toxicant Exposure

DTIC Science & Technology

2000-09-30

Modeling Population and Ecosystem Response to Sublethal Toxicant Exposure Principal Investigator: Roger M. Nisbet Department of Ecology, Evolution...DATES COVERED 00-00-2000 to 00-00-2000 4. TITLE AND SUBTITLE Modeling Population and Ecosystem Response to Sublethal Toxicant Exposure 5a...those of real populations. We have also investigated how toxicants may affect the stability of the system. If the toxicant effect is primarily an

Population exposure to heat-related extremes: Demographic change vs climate change

NASA Astrophysics Data System (ADS)

Jones, B.; O'Neill, B. C.; Tebaldi, C.; Oleson, K. W.

2014-12-01

Extreme heat events are projected to increase in frequency and intensity in the coming decades [1]. The physical effects of extreme heat on human populations are well-documented, and anticipating changes in future exposure to extreme heat is a key component of adequate planning/mitigation [2, 3]. Exposure to extreme heat depends not only on changing climate, but also on changes in the size and spatial distribution of the human population. Here we focus on systematically quantifying exposure to extreme heat as a function of both climate and population change. We compare exposure outcomes across multiple global climate and spatial population scenarios, and characterize the relative contributions of each to population exposure to extreme heat. We consider a 2 x 2 matrix of climate and population output, using projections of heat extremes corresponding to RCP 4.5 and RCP 8.5 from the NCAR community land model, and spatial population projections for SSP 3 and SSP 5 from the NCAR spatial population downscaling model. Our primary comparison is across RCPs - exposure outcomes from RCP 4.5 versus RCP 8.5 - paying particular attention to how variation depends on the choice of SSP in terms of aggregate global and regional exposure, as well as the spatial distribution of exposure. We assess how aggregate exposure changes based on the choice of SSP, and which driver is more important, population or climate change (i.e. does that outcome vary more as a result of RCP or SSP). We further decompose the population component to analyze the contributions of total population change, migration, and changes in local spatial structure. Preliminary results from a similar study of the US suggests a four-to-six fold increase in total exposure by the latter half of the 21st century. Changes in population are as important as changes in climate in driving this outcome, and there is regional variation in the relative importance of each. Aggregate population growth, as well as redistribution of

Exposure of the general population to gasoline.

PubMed Central

Akland, G G

1993-01-01

This paper summarizes the currently available information on gasoline exposure to the general population. In general, the largest contribution to the time weighted exposures results from exposures while indoors, which are influenced by the outside air, indoor sources, and attached garages. Personal activities, including refueling and commuting, contribute significantly higher exposures but last for only a small portion of the 24-hr time weighted average. The highest exposed group includes those individuals living near large service stations and those with contaminated water supplies. PMID:8020446

POPULATION EXPOSURES TO PARTICULATE MATTER: A COMPARISON OF EXPOSURE MODEL PREDICTIONS AND MEASUREMENT DATA

EPA Science Inventory

The US EPA National Exposure Research Laboratory (NERL) is currently developing an integrated human exposure source-to-dose modeling system (HES2D). This modeling system will incorporate models that use a probabilistic approach to predict population exposures to environmental ...

The Relationship between Posttraumatic and Depressive Symptoms during Prolonged Exposure with and without Cognitive Restructuring for the Treatment of Posttraumatic Stress Disorder

ERIC Educational Resources Information Center

Aderka, Idan M.; Gillihan, Seth J.; McLean, Carmen P.; Foa, Edna B.

2013-01-01

Objective: In the present study, we examined the relationship between posttraumatic and depressive symptoms during prolonged exposure (PE) treatment with and without cognitive restructuring (CR) for the treatment of posttraumatic stress disorder (PTSD). Method: Female assault survivors (N = 153) with PTSD were randomized to either PE alone or PE…

Genocide Exposure and Subsequent Suicide Risk: A Population-Based Study

PubMed Central

Levine, Stephen Z.; Levav, Itzhak; Yoffe, Rinat; Becher, Yifat; Pugachova, Inna

2016-01-01

The association between periods of genocide-related exposures and suicide risk remains unknown. Our study tests that association using a national population-based study design. The source population comprised of all persons born during1922-1945 in Nazi-occupied or dominated European nations, that immigrated to Israel by 1965, were identified in the Population Register (N = 220,665), and followed up for suicide to 2014, totaling 16,953,602 person-years. The population was disaggregated to compare a trauma gradient among groups that immigrated before (indirect, n = 20,612, 9%); during (partial direct, n = 17,037, 8%); or after (full direct, n = 183,016, 83%) exposure to the Nazi era. Also, the direct exposure groups were examined regarding pre- or post-natal exposure periods. Cox regression models were used to compute Hazard Ratios (HR) of suicide risk to compare the exposure groups, adjusting for confounding by gender, residential SES and history of psychiatric hospitalization. In the total population, only the partial direct exposure subgroup was at greater risk compared to the indirect exposure group (HR = 1.73, 95% CI, 1.10, 2.73; P < .05). That effect replicated in six sensitivity analyses. In addition, sensitivity analyses showed that exposure at ages 13 plus among females, and follow-up by years since immigration were associated with a greater risk; whereas in utero exposure among persons with no psychiatric hospitalization and early postnatal exposure among males were at a reduced risk. Tentative mechanisms impute biopsychosocial vulnerability and natural selection during early critical periods among males, and feelings of guilt and entrapment or defeat among females. PMID:26901411

Prolonged exposure does not increase soil microbial community compositional response to warming along geothermal gradients.

PubMed

Radujkovic, Dajana; Verbruggen, Erik; Sigurdsson, Bjarni D; Leblans, Niki I W; Janssens, Ivan A; Vicca, Sara; Weedon, James T

2018-02-01

Global change is expected to affect soil microbial communities through their responsiveness to temperature. It has been proposed that prolonged exposure to elevated temperatures may lead to progressively larger effects on soil microbial community composition. However, due to the relatively short-term nature of most warming experiments, this idea has been challenging to evaluate. The present study took the advantage of natural geothermal gradients (from +1°C to +19°C above ambient) in two subarctic grasslands to test the hypothesis that long-term exposure (>50 years) intensifies the effect of warming on microbial community composition compared to short-term exposure (5-7 years). Community profiles from amplicon sequencing of bacterial and fungal rRNA genes did not support this hypothesis: significant changes relative to ambient were observed only starting from the warming intensity of +9°C in the long term and +7°C/+3°C in the short term, for bacteria and fungi, respectively. Our results suggest that microbial communities in high-latitude grasslands will not undergo lasting shifts in community composition under the warming predicted for the coming 100 years (+2.2°C to +8.3°C). © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Modeling population exposures to silver nanoparticles present in consumer products

NASA Astrophysics Data System (ADS)

Royce, Steven G.; Mukherjee, Dwaipayan; Cai, Ting; Xu, Shu S.; Alexander, Jocelyn A.; Mi, Zhongyuan; Calderon, Leonardo; Mainelis, Gediminas; Lee, KiBum; Lioy, Paul J.; Tetley, Teresa D.; Chung, Kian Fan; Zhang, Junfeng; Georgopoulos, Panos G.

2014-11-01

Exposures of the general population to manufactured nanoparticles (MNPs) are expected to keep rising due to increasing use of MNPs in common consumer products (PEN 2014). The present study focuses on characterizing ambient and indoor population exposures to silver MNPs (nAg). For situations where detailed, case-specific exposure-related data are not available, as in the present study, a novel tiered modeling system, Prioritization/Ranking of Toxic Exposures with GIS (geographic information system) Extension (PRoTEGE), has been developed: it employs a product life cycle analysis (LCA) approach coupled with basic human life stage analysis (LSA) to characterize potential exposures to chemicals of current and emerging concern. The PRoTEGE system has been implemented for ambient and indoor environments, utilizing available MNP production, usage, and properties databases, along with laboratory measurements of potential personal exposures from consumer spray products containing nAg. Modeling of environmental and microenvironmental levels of MNPs employs probabilistic material flow analysis combined with product LCA to account for releases during manufacturing, transport, usage, disposal, etc. Human exposure and dose characterization further employ screening microenvironmental modeling and intake fraction methods combined with LSA for potentially exposed populations, to assess differences associated with gender, age, and demographics. Population distributions of intakes, estimated using the PRoTEGE framework, are consistent with published individual-based intake estimates, demonstrating that PRoTEGE is capable of capturing realistic exposure scenarios for the US population. Distributions of intakes are also used to calculate biologically relevant population distributions of uptakes and target tissue doses through human airway dosimetry modeling that takes into account product MNP size distributions and age-relevant physiological parameters.

Dynamics of immediate early gene and neuropeptide gene response to prolonged immobilization stress: evidence against a critical role of the termination of exposure to the stressor.

PubMed

Trnecková, Lenka; Rotllant, David; Klenerová, Vera; Hynie, Sixtus; Armario, Antonio

2007-02-01

Stress-induced expression of immediate early genes (IEGs) appears to be transient even if the exposure to the stressor persists. However, there are some exceptions which suggest that particular characteristics of stressors can affect the dynamics of IEG expression. We studied in selected telencephalic, diencephalic and brainstem regions the mRNA levels of two clearly distinct IEGs (c-fos and arc) during prolonged exposure to a severe stressor such as immobilization (IMO) and after releasing the rats from the situation. Although regional differences were observed with the two IEGs, overall, c-fos mRNA levels progressively declined over the course of 4 h of continuous exposure to IMO, whereas arc mRNA levels were maintained at high levels in the brain regions that express this gene under stress (telencephalon). Levels of CRF hnRNA in the hypothalamus paraventricular nucleus only slightly declined during prolonged exposure to IMO. Surprisingly, termination of exposure to IMO did not modify CRF gene expression in the paraventricular nucleus or the pattern of IEGs expression, with the exception of c-fos in the lateral septum. Thus, putative signals associated to the termination of exposure to IMO were unable to modify either IEG expression in most brain areas or CRF gene expression in the paraventricular nucleus.

A statistical framework for the validation of a population exposure model based on personal exposure data

NASA Astrophysics Data System (ADS)

Rodriguez, Delphy; Valari, Myrto; Markakis, Konstantinos; Payan, Sébastien

2016-04-01

Currently, ambient pollutant concentrations at monitoring sites are routinely measured by local networks, such as AIRPARIF in Paris, France. Pollutant concentration fields are also simulated with regional-scale chemistry transport models such as CHIMERE (http://www.lmd.polytechnique.fr/chimere) under air-quality forecasting platforms (e.g. Prev'Air http://www.prevair.org) or research projects. These data may be combined with more or less sophisticated techniques to provide a fairly good representation of pollutant concentration spatial gradients over urban areas. Here we focus on human exposure to atmospheric contaminants. Based on census data on population dynamics and demographics, modeled outdoor concentrations and infiltration of outdoor air-pollution indoors we have developed a population exposure model for ozone and PM2.5. A critical challenge in the field of population exposure modeling is model validation since personal exposure data are expensive and therefore, rare. However, recent research has made low cost mobile sensors fairly common and therefore personal exposure data should become more and more accessible. In view of planned cohort field-campaigns where such data will be available over the Paris region, we propose in the present study a statistical framework that makes the comparison between modeled and measured exposures meaningful. Our ultimate goal is to evaluate the exposure model by comparing modeled exposures to monitor data. The scientific question we address here is how to downscale modeled data that are estimated on the county population scale at the individual scale which is appropriate to the available measurements. To assess this question we developed a Bayesian hierarchical framework that assimilates actual individual data into population statistics and updates the probability estimate.

Satellite-aided evaluation of population exposure to air pollution

USGS Publications Warehouse

Todd, William J.; George, Anthony J.; Bryant, Nevin A.

1979-01-01

The Clean Air Act Amendments of 1977 set schedules for states to implement regional, spatial assessments of air quality impacts. Accordingly, the U.S. Environmental Protection Agency recently published guidelines for quantifying population exposure to adverse air quality impact by using air quality and population data by census tracts. Our research complements the EPA guidelines in that it demonstrates the ability to determine population exposure to air pollution through computer processing that utilizes Landsat satellite-derived land use information. Three variables-a 1985 estimate of total suspended particulates for 2-km2 grid cells, Landsat-derived residential land cover data for 0.45-ha cells, and population totals for census tracts-were spatially registered and cross-tabulated to produce tabular and map products illustrating relative air quality exposure for residential population by 2-km2 cells. It would cost $20,000 to replicate our analysis for an area similar in size to the 4000-km2 Portland area. Once completed, the spatially fine, computer-compatible air quality and population data are amenable to the timely and efficient generation of population-at-risk tabular and map information on a continuous or periodic basis.

Exposure to contaminants and nutritional intakes in a French vegetarian population.

PubMed

Fleury, S; Rivière, G; Allès, B; Kesse-Guyot, E; Méjean, C; Hercberg, S; Touvier, M; Bemrah, N

2017-11-01

The NutriNet Santé study collected, on a voluntary basis, the dietary consumption of French vegetarian populations (N = 1766, including 188 vegan individuals) from 18 to 81 years (18-77 years for the vegan). Taking advantage of the availability of contamination data generated in the context of the second French total diet study, dietary exposures of French vegetarian populations to several contaminants were estimated. Results showed that exposures to persistent organic pollutants (PCBs, PCDD/Fs for instance) was dramatically lower than those of the general French population due to the non consumption of food of animal origins. On the other hand, exposures to phytoestrogens, some mycotoxins (T2 and HT2 toxins) and some trace elements (Cd, Al, Sn, Ni) were higher in the vegetarian population compared to those of the general population. Despite some limitations of this approach (both the consumption study and the total diet study were not aimed to estimate dietary exposure of the vegetarian populations), this study showed that dietary habits can dramatically influence the exposure of some contaminants. Copyright © 2017 Elsevier Ltd. All rights reserved.

Changes in CR-39 proton sensitivity due to prolonged exposure to high vacuums relevant to the National Ignition Facility and OMEGA.

PubMed

Manuel, M J-E; Rosenberg, M J; Sinenian, N; Rinderknecht, H; Zylstra, A B; Séguin, F H; Frenje, J; Li, C K; Petrasso, R D

2011-09-01

When used at facilities like OMEGA and the NIF, CR-39 is exposed to high vacuum environments before and after irradiation by charged particles and neutrons. Using an electrostatic linear accelerator at MIT, studies have been conducted to investigate the effects of high vacuum exposure on the sensitivity of CR-39 to fusion protons in the ~1-9 MeV energy range. High vacuum conditions, of order 10(-5) Torr, experienced by CR-39 samples at these facilities were emulated. It is shown that vacuum exposure times longer than ~16 h before proton irradiation result in a decrease in proton sensitivity, whereas no effect was observed for up to 67 h of vacuum exposure after proton irradiation. CR-39 sensitivity curves are presented for samples with prolonged exposure to high vacuum before and after proton irradiation. © 2011 American Institute of Physics

A POPULATION EXPOSURE MODEL FOR PARTICULATE MATTER: SHEDS-PM

EPA Science Inventory

The US EPA National Exposure Research Laboratory (NERL) has developed a population exposure and dose model for particulate matter (PM) that will be publicly available in Fall 2002. The Stochastic Human Exposure and Dose Simulation (SHEDS-PM) model uses a probabilistic approach ...

DIETARY EXPOSURE TO PYRETHROIDS IN THE U.S POPULATION

EPA Science Inventory

We examined the contribution of pyrethroid residues in food as an important driver of exposure. The levels of urinary metabolites of pyrethroids reported in NHANES were used as a general estimate of population exposure to pyrethroids. Dietary exposure to pyrethroids was estimat...

Signal transduction disturbance related to hepatocarcinogenesis in mouse by prolonged exposure to Nanjing drinking water.

PubMed

Zhang, Rui; Sun, Jie; Zhang, Yan; Cheng, Shupei; Zhang, Xiaowei

2013-09-01

Toxicogenomic approaches were used to investigate the potential hepatocarcinogenic effects on mice by oral exposure to Nanjing drinking water (NJDW). Changes in the hepatic transcriptome of 3 weeks male mice (Mus musculus) were monitored and dissected after oral exposure to NJDW for 90 days. No preneoplastic and neoplastic lesions were observed in the hepatic tissue by the end of NJDW exposure. However, total of 746 genes were changed transcriptionally. Thirty-one percent of differentially expressed genes (DEGs) were associated with the functional categories of cell cycle regulation, adhesion, growth, apoptosis, and signal transduction, which are closely implicated in tumorigenesis and progression. Interrogation of Kyoto Encyclopedia of Genes and Genomes revealed that 43 DEGs were mapped to several crucial signaling pathways implicated in the pathogenesis of hepatocellular carcinoma (HCC). In signal transduction network constructed via Genes2Networks software, Egfr, Akt1, Atf2, Ctnnb1, Hras, Mapk1, Smad2, and Ccnd1 were hubs. Direct gene-disease relationships obtained from Comparative Toxicogenomics Database and scientific literatures revealed that the hubs have direct mechanism or biomarker relationships with hepatocellular preneoplastic lesions or hepatocarcinogenesis. Therefore, prolonged intake of NJDW without employing any indoor water treatment strategy might predispose mouse to HCC. Furthermore, Egfr, Akt1, Ctnnb1, Hras, Mapk1, Smad2, and Ccnd1 were identified as promising biomarkers of the potential combined hepatocarcinogenicity.

The "PE coach" smartphone application: an innovative approach to improving implementation, fidelity, and homework adherence during prolonged exposure.

PubMed

Reger, Greg M; Hoffman, Julia; Riggs, David; Rothbaum, Barbara O; Ruzek, Josef; Holloway, Kevin M; Kuhn, Eric

2013-08-01

Prolonged exposure (PE) is an empirically supported treatment that is being disseminated broadly to providers in the Department of Veterans Affairs and Department of Defense. Innovative methods are needed to support the implementation, dissemination, and patient and provider adherence to PE. The PE Coach is a smartphone application (app) designed to mitigate barriers to PE implementation. PE Coach is installed on the patient's phone and includes a range of capabilities for use during the PE session and after each session to support the treatment. Functions include the ability to audio record treatment sessions onto the patient's device, to construct the in vivo hierarchy on the device, to record completed homework exercises, to review homework adherence, and to track symptom severity over time. The app also allows sessions and homework to be scheduled directly in the app, populating the device calendar with patient reminder notifications. In the final session, a visual display of symptom improvement and habituation to items on the in vivo hierarchy is presented. These capabilities may significantly improve convenience, provider implementation and adherence, and patient compliance with treatment. Future research is needed to test whether PE Coach is useful and effective. PsycINFO Database Record (c) 2013 APA, all rights reserved.

Sympathetic neural overactivity in healthy humans after prolonged exposure to hypobaric hypoxia

PubMed Central

Hansen, Jim; Sander, Mikael

2003-01-01

Acute exposure to hypoxia causes chemoreflex activation of the sympathetic nervous system. During acclimatization to high altitude hypoxia, arterial oxygen content recovers, but it is unknown to what degree sympathetic activation is maintained or normalized during prolonged exposure to hypoxia. We therefore measured sympathetic nerve activity directly by peroneal microneurography in eight healthy volunteers (24 ± 2 years of age) after 4 weeks at an altitude of 5260 m (Chacaltaya, Bolivian Andes) and at sea level (Copenhagen). The subjects acclimatized well to altitude, but in every subject sympathetic nerve activity was highly elevated at altitude vs. sea level (48 ± 5 vs. 16 ± 3 bursts min−1, respectively, P < 0.05), coinciding with increased mean arterial blood pressure (87 ± 3 vs. 77 ± 2 mmHg, respectively, P < 0.05). To examine the underlying mechanisms, we administered oxygen (to eliminate chemoreflex activation) and saline (to reduce cardiopulmonary baroreflex deactivation). These interventions had minor effects on sympathetic activity (48 ± 5 vs. 38 ± 4 bursts min−1, control vs. oxygen + saline, respectively, P < 0.05). Moreover, sympathetic activity was still markedly elevated (37 ± 5 bursts min−1) when subjects were re-studied under normobaric, normoxic and hypervolaemic conditions 3 days after return to sea level. In conclusion, acclimatization to high altitude hypoxia is accompanied by a striking and long-lasting sympathetic overactivity. Surprisingly, chemoreflex activation by hypoxia and baroreflex deactivation by dehydration together could account for only a small part of this response, leaving the major underlying mechanisms unexplained. PMID:12563015

Effects of prolonged exposure and virtual reality exposure on suicidal ideation in active duty soldiers: An examination of potential mechanisms.

PubMed

Norr, Aaron M; Smolenski, Derek J; Reger, Greg M

2018-05-12

The current study sought to investigate the effects of exposure therapy on suicidal ideation (SI), as well as potential mechanistic pathways of SI reduction among active duty military personnel. Active duty army soldiers (N = 162) were recruited from a military base in the U.S. and were enrolled in a randomized clinical trial comparing Prolonged Exposure (PE), Virtual Reality Exposure (VRE), and a wait-list control for the treatment of posttraumatic stress disorder (PTSD) stemming from deployments to Iraq or Afghanistan. PTSD diagnosis followed DSM-IV-TR criteria. Outcome measures were assessed via self-report and clinician interview. PTSD symptoms, depressive symptoms, and SI were included in an autoregressive cross-lagged panel model to examine mechanistic pathways. Analyses revealed that PE/VRE had a lower probability of post-treatment suicidal ideation (OR = 0.23, 95% CI [0.06, 0.86]) compared to the waitlist control. Mediation analyses revealed a significant indirect effect from treatment condition to post-treatment PTSD symptoms through mid-treatment SI (Estimate = -1.420, 95% CI -3.559, -0.223]). Baseline suicidal ideation did not interact with treatment condition to predict PTSD symptom change at mid-treatment (p = .231) or post-treatment (p = .672). PE/VRE successfully reduced SI, and the presence of SI at baseline did not affect PTSD symptom reduction, promoting the utility of using PE/VRE to address suicidality among individuals with PTSD. Mediation analyses suggest that reductions in SI were achieved early in treatment. Published by Elsevier Ltd.

Glycyrrhizin Treatment Facilitates Extinction of Conditioned Fear Responses After a Single Prolonged Stress Exposure in Rats.

PubMed

Lai, Shuhua; Wu, Gangwei; Jiang, Zhixian

2018-01-01

Impaired fear memory extinction is widely considered a key mechanism of post-traumatic stress disorder (PTSD). Recent studies have suggested that neuroinflammation after a single prolonged stress (SPS) exposure may play a critical role in the impaired fear memory extinction. Studies have shown that high mobility group box chromosomal protein 1 (HMGB-1) is critically involved in neuroinflammation. However, the role of HMGB-1 underlying the development of impairment of fear memory extinction is still not known. Thus, we examined the levels of HMGB-1 in the basolateral amygdala (BLA) following SPS using Western blot and evaluated the levels of microglia and astrocytes activation in the BLA after SPS using immunohistochemical staining. We then examined the effects of pre-SPS intra-BLA administration of glycyrrhizin, an HMGB1 inhibitor, or LPS-RS, a competitive TLR4 antagonist, on subsequent post-SPS fear extinction. We found that SPS treatment prolonged the extinction of contextual fear memory after the SPS. The impairment of SPS-induced extinction of contextual fear memory was associated with increased HMGB1 and Toll-like receptor 4 (TLR4) levels in the BLA. Additionally, the impairment of SPS-induced extinction of contextual fear memory was associated with increased activation of microglia and astrocyte in the BLA. Intra-BLA administrations of glycyrrhizin (HMGB-1 inhibitor) or LPS-RS (TLR4 antagonist) can prevent the development of SPS-induced fear extinction impairment. Taken together, these results suggested that SPS treatment may not only produce short term effects on the HMGB1/TLR4-mediated pro-inflammation, but alter the response of microglia and astrocytes to the exposure to fear associated contextual stimuli. © 2018 The Author(s). Published by S. Karger AG, Basel.

Prolonged Cough in Pediatric Population First Line Care, Belgian Guidelines

PubMed Central

Leconte, Sophie; Valentin, Stéphanie; Dromelet, Estelle; De Jonghe, Michel

2017-01-01

Background: The clinical approach to a prolonged cough, i.e. a cough lasting more than three weeks, is challenging for general practitioners as well for primary care pediatricians. What the recommended clinical approach in primary care is, how cough duration or cough characteristics impact the diagnosis, and what the efficiency and safety of antibiotics or symptomatic treatments are remain in question for primary care physicians. Objective: The last Belgian guidelines were published in 2006 and needed to be reviewed. Those background questions were used to conduct our guideline updating procedure. Methods: We systematically performed a pyramidal literature search between the periods 2006-2014 in order to write evidence based guidelines. The data of the literature was summarized, discussed by the authors, experts and the Belgian primary care guidelines committee. Recommendations were formulated and scored following the GRADE classification. Results: The consultation history as well as the physical examination should be directed towards searching for warning signs (GRADE 1B) and towards the common etiologies depending on cough duration (GRADE 2C). If the cough lasts for more than eight weeks, chest radiography and spirometry should be considered (GRADE 2C). An antibiotic is recommended for a prolonged wet cough (over eight weeks) if prolonged bacterial bronchitis is suspected (GRADE 1B). In the absence of clinical signs of a specific etiology of a cough, no drug can be recommended (GRADE 1B). For all cases, it is initially suggested to avoid irritants (GRADE 1C) as well as to take into account the concerns of parents and inform them about the natural development of a cough. Conclusions: More research is needed to provide evidence on the clinical pathway on prolonged cough for primary care. Cough duration of more than eight weeks and prolonged wet cough are the most useful cough characteristics. Regarding a specific cough treatment, no medication has proved any effect

Occupational airborne exposure of the general population of a Norwegian county.

PubMed

Bakke, P; Baste, V; Hanoa, R; Gulsvik, A

1992-02-01

Occupational airborne exposure was examined for a stratified sample (N = 1275) of the general population aged 18-73 years in Hordaland County, Norway. The subjects identified all jobs of more than six months since leaving school and stated whether they had been occupationally exposed to specific agents and work processes potentially harmful to the lungs. The prevalence in the population ever having been exposed was 18% for asbestos, 9% for quartz, 5% for aluminum dust, 6% for wood dust, 12% for metal gases, 12% for welding, 9% for soldering, and 1% for hairdressing. According to occupational title (last job), 3% of the population had held a job with a high degree of airborne exposure, 26% a job with moderate exposure, and 70% a job with no airborne exposure. During their worklife both the men and the women tended to leave polluted jobs more often than unpolluted jobs. Occupational exposure to airborne pollutants potentially harmful to the lungs is widespread in this Norwegian general population.

[The key problems in the population exposure assessment of hazardous chemicals accidents].

PubMed

Pan, L J; Liu, F P; Zhang, X; Bai, X T; Shi, X M

2016-07-06

Serious accidents of hazardous chemicals can cause a variety of acute or chronic impairment in human health. The effects of hazardous chemicals on human health can be identified by carrying on population exposure assessment. Through analyzing the domestic and overseas population exposure assessment cases related to hazardous chemicals accidents, we summarized that the base and key of the population exposure assessment were to identify the characteristics of the chemicals , delimit the area and the population exposed to the chemicals, and collect the data of the monitored chemicals and the population health in the polluted area.

Intraocular pressure and cerebral oxygenation during prolonged headward acceleration.

PubMed

Eiken, Ola; Keramidas, Michail E; Taylor, Nigel A S; Grönkvist, Mikael

2017-01-01

Supra-tolerance head-to-foot directed gravitoinertial load (+Gz) typically induces a sequence of symptoms/signs, including loss of: peripheral vision-central vision-consciousness. The risk of unconsciousness is greater when anti-G-garment failure occurs after prolonged rather than brief exposures, presumably because, in the former condition, mental signs are not consistently preceded by impaired vision. The aims were to investigate if prolonged exposure to moderately elevated +Gz reduces intraocular pressure (IOP; i.e., improves provisions for retinal perfusion), or the cerebral anoxia reserve. Subjects were exposed to 4-min +Gz plateaux either at 2 and 3 G (n = 10), or at 4 and 5 G (n = 12). Measurements included eye-level mean arterial pressure (MAP), oxygenation of the cerebral frontal cortex, and at 2 and 3 G, IOP. IOP was similar at 1 (14.1 ± 1.6 mmHg), 2 (14.0 ± 1.6 mmHg), and 3 G (14.0 ± 1.6 mmHg). During the G exposures, MAP exhibited an initial prompt drop followed by a partial recovery, end-exposure values being reduced by ≤30 mmHg. Cerebral oxygenation showed a similar initial drop, but without recovery, and was followed by either a plateau or a further slight decrement to a minimum of about -14 μM. Gz loading did not affect IOP. That cerebral oxygenation remained suppressed throughout these G exposures, despite a concomitant partial recovery of MAP, suggests that the increased risk of unconsciousness upon G-garment failure after prolonged +Gz exposure is due to reduced cerebral anoxia reserve.

Estimation of the dietary acrylamide exposure of the Polish population.

PubMed

Mojska, Hanna; Gielecińska, Iwona; Szponar, Lucjan; Ołtarzewski, Maciej

2010-01-01

The objective of our study was to determine acrylamide content in the Polish foods and to assess the average dietary acrylamide exposure of the Polish population. We analysed the acrylamide content in Polish food using GCQ-MS/MS method. The daily dietary acrylamide exposure was computed using a probabilistic approach for the total Polish population (1-96 years) and for the following age groups: 1-6, 7-18 and 19-96, using Monte Carlo simulation technique. To assess the Polish population exposure to acrylamide present in food, food consumption data was taken from the 'Household Food Consumption and Anthropometric Survey in Poland'. The mean content of acrylamide in tested 225 samples of foodstuffs taken randomly all over Poland, ranged widely from 11 to 3647 microg/kg of product. For the total Polish population (1-96 years) the estimated acrylamide mean exposure is 0.43 microg/kg of body weight per day. The main sources of dietary acrylamide in Polish population were as follow: bread--supplied 45% of total dietary acrylamide intake, French fries and potato crisps--23%, roasted coffee--19%. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Treating Low-Income and Minority Women with Posttraumatic Stress Disorder: A Pilot Study Comparing Prolonged Exposure and Treatment as Usual Conducted by Community Therapists

ERIC Educational Resources Information Center

Feske, Ulrike

2008-01-01

Twenty-one female psychiatric outpatients with chronic posttraumatic stress disorder (PTSD) are randomly assigned to prolonged exposure (PE; n = 9) for PTSD or treatment as usual (TAU; n = 12). Participants are predominately low income and African American with complex trauma and psychiatric histories. Treatment is delivered by community…

Effects of five sulphonamides on duckweed (Lemna minor) after prolonged exposure time and their dependency on photoradiation.

PubMed

Białk-Bielińska, Anna; Matzke, Marianne; Caban, Magda; Stolte, Stefan; Kumirska, Jolanta; Stepnowski, Piotr

2018-03-15

Sulphonamides (SAs) are one of the most commonly used veterinary drugs and therefore their residues are regularly found in the environment. So far scientific attention has mostly been paid to the evaluation of their acute ecotoxicological effects with data on long-term effects for non-target organisms still largely missing. Therefore, the main aim of this study was to evaluate the potential toxicities of five sulphonamides to duckweed (Lemna minor) after prolonged exposure time (14days). To elucidate whether their phytotoxic effects result from potential photodegradation products, the toxicity of standard solutions of selected sulphonamides was also investigated in a standard 7-day test but after irradiation (by keeping them under the test conditions) for the selected time (after 7 and 14days). The ecotoxicological tests were accompanied by chemical analyses to be able to link the observed effects to the concentrations and nature of the exposed compounds. The results showed a shift in the toxicity of SAs: a strong decrease in toxicity for the two most toxic sulphonamides (sulphamethoxazole and sulphadimethoxine) and a slight increase in toxicity for three other SAs (sulphadimidine, sulphathiazole, sulphamerazine) in the prolonged test. However, a decrease in the toxicity and concentration of all the SAs was observed when stock solutions were irradiated prior to the toxicity experiment, which suggests that the observed effects towards L. minor of five SAs in the prolonged test cannot be directly associated with the degradation of these compounds under the test conditions but with their different mode of toxic action towards these organisms. Copyright © 2017 Elsevier B.V. All rights reserved.

Bisphenol A exposure and cardiac electrical conduction in excised rat hearts.

PubMed

Posnack, Nikki Gillum; Jaimes, Rafael; Asfour, Huda; Swift, Luther M; Wengrowski, Anastasia M; Sarvazyan, Narine; Kay, Matthew W

2014-04-01

Bisphenol A (BPA) is used to produce polycarbonate plastics and epoxy resins that are widely used in everyday products, such as food and beverage containers, toys, and medical devices. Human biomonitoring studies have suggested that a large proportion of the population may be exposed to BPA. Recent epidemiological studies have reported correlations between increased urinary BPA concentrations and cardiovascular disease, yet the direct effects of BPA on the heart are unknown. The goal of our study was to measure the effect of BPA (0.1-100 μM) on cardiac impulse propagation ex vivo using excised whole hearts from adult female rats. We measured atrial and ventricular activation times during sinus and paced rhythms using epicardial electrodes and optical mapping of transmembrane potential in excised rat hearts exposed to BPA via perfusate media. Atrioventricular activation intervals and epicardial conduction velocities were computed using recorded activation times. Cardiac BPA exposure resulted in prolonged PR segment and decreased epicardial conduction velocity (0.1-100 μM BPA), prolonged action potential duration (1-100 μM BPA), and delayed atrioventricular conduction (10-100 μM BPA). These effects were observed after acute exposure (≤ 15 min), underscoring the potential detrimental effects of continuous BPA exposure. The highest BPA concentration used (100 μM) resulted in prolonged QRS intervals and dropped ventricular beats, and eventually resulted in complete heart block. Our results show that acute BPA exposure slowed electrical conduction in excised hearts from female rats. These findings emphasize the importance of examining BPA's effect on heart electrophysiology and determining whether chronic in vivo exposure can cause or exacerbate conduction abnormalities in patients with preexisting heart conditions and in other high-risk populations.

A PROBABILISTIC POPULATION EXPOSURE MODEL FOR PM10 AND PM 2.5

EPA Science Inventory

A first generation probabilistic population exposure model for Particulate Matter (PM), specifically for predicting PM10, and PM2.5, exposures of an urban, population has been developed. This model is intended to be used to predict exposure (magnitude, frequency, and duration) ...

Coexistence of Ureaplasma and chorioamnionitis is associated with prolonged mechanical ventilation.

PubMed

Jung, Euiseok; Choi, Chang Won; Kim, Su Yeong; Sung, Tae-Jung; Kim, Haeryoung; Park, Kyoung Un; Kim, Han-Suk; Kim, Beyong Il; Choi, Jung-Hwan

2017-01-01

Both histologic chorioamnionitis (HCAM) and Ureaplasma infection are considered important contributors to perinatal lung injury. We tested the hypothesis that coexistence of maternal HCAM and perinatal Ureaplasma exposure increases the risk of prolonged mechanical ventilation in extremely low-birthweight (ELBW) infants. A retrospective cohort study was carried out of all ELBW infants born between January 2008 and December 2013 at a single academic center. Placental pathology and gastric fluid Ureaplasma data were available for all infants. Culture and polymerase chain reaction were used to detect Ureaplasma in gastric fluid. Prolonged mechanical ventilation was defined as mechanical ventilation that began within 28 days after birth and continued. Of 111 ELBW infants enrolled, 84 survived beyond 36 weeks of postmenstrual age (PMA) and were included in the analysis. Eighteen infants (21.4%) had both HCAM and Ureaplasma exposure. Seven infants (8.3%) required mechanical ventilation beyond 36 weeks of PMA. Coexistence of HCAM and Ureaplasma in gastric fluid was significantly associated with prolonged mechanical ventilation after adjustment for gestational age, sex, mode of delivery, and use of macrolide antibiotics (OR, 8.7; 95%CI: 1.1-67.2). Coexistence of maternal HCAM and perinatal Ureaplasma exposure significantly increases the risk of prolonged mechanical ventilation in ELBW infants. © 2016 Japan Pediatric Society.

Prolonged exposure for the treatment of Spanish-speaking Puerto Ricans with posttraumatic stress disorder: a feasibility study

PubMed Central

2011-01-01

Background Most of the empirical studies that support the efficacy of prolonged exposure (PE) for treating posttraumatic stress disorder (PTSD) have been conducted on white mainstream English-speaking populations. Although high PTSD rates have been reported for Puerto Ricans, the appropriateness of PE for this population remains unclear. The purpose of this study was to examine the feasibility of providing PE to Spanish speaking Puerto Ricans with PTSD. Particular attention was also focused on identifying challenges faced by clinicians with limited experience in PE. This information is relevant to help inform practice implications for training Spanish-speaking clinicians in PE. Results Fourteen patients with PTSD were randomly assigned to receive PE (n = 7) or usual care (UC) (n = 7). PE therapy consisted of 15 weekly sessions focused on gradually confronting and emotionally processing distressing trauma-related memories and reminders. Five patients completed PE treatment; all patients attended the 15 sessions available to them. In UC, patients received mental health services available within the health care setting where they were recruited. They also had the option of self-referring to a mental health provider outside the study setting. The Clinician-Administered PTSD Scale (CAPS) was administered at baseline, mid-treatment, and post-treatment to assess PTSD symptom severity. Treatment completers in the PE group demonstrated significantly greater reductions in PTSD symptoms than the UC group. Forty percent of the PE patients showed clinically meaningful reductions in PTSD symptoms from pre- to post-treatment. Conclusions PE appears to be viable for treating Puerto Rican Spanish-speaking patients with PTSD. This therapy had good patient acceptability and led to improvements in PTSD symptoms. Attention to the clinicians' training process contributed strongly to helping them overcome the challenges posed by the intervention and increased their acceptance of PE. PMID

Heat exposure in cities: combining the dynamics of temperature and population

NASA Astrophysics Data System (ADS)

Hu, L.; Wilhelmi, O.; Uejio, C. K.

2017-12-01

Assessment of human exposure to extreme heat requires the distributions of temperature and population. However, both variables are dynamic, thus presenting many challenges in capturing temperature and population patterns spatially and over time in an urban context. This study aims to improve the understanding of spatiotemporal patterns of urban population exposure to heat, taking Chicago, USA as an example. We estimate the hourly, geographically variable, population distribution considering commute of workers and students in a regular weekday and analyze the diurnal air temperature patterns during different meteorological conditions from satellite observations. The results show a relatively larger temperature increase in less urbanized areas during extreme heat events (EHEs), resulting in a spatially homogeneous temperature distribution over Chicago Metropolitan area. A lake cooling effect is weaker during EHEs. Population dynamics due to daily commute determine higher population density in more urbanized areas during daytime. The city-wide analysis reveals that the exposure is more sensitive to the nighttime temperature increases, and EHEs enhance this sensitivity. The high exposure hotspots are identified at the northwest Chicago, Cicero and Oak Park areas, where the influence from Lake Michigan is weakened, while the spatial extent of high outdoor exposure areas varies diurnally. This study's findings have potential to better inform general heat mitigation strategies during hot summer months and facilitate emergency response during EHEs. Availability of remotely-sensed temperature observations as well as the workers and students commute-adjusted population data allows for the adoption of this study's methodology in other major metropolitan areas. A better understanding of space-time patterns of urban population's exposure to heat will further enable local decision makers to mitigate extreme heat health risks and develop more targeted heat preparedness and

PROJECTING THE RESPONSE OF FISH POPULATION GROWTH RATE TO SEDIMENT EXPOSURE

EPA Science Inventory

Sediment is one of the main stressors on stream fish populations in Georgia. Here, a quantitative approach relating sediment exposure to stream fish population dynamics is presented, where equations characterize sediment exposure to vital rates, then vital rates are used in a mat...

THE CONTRIBUTION OF AMBIENT PM2.5 TO TOTAL PERSONAL EXPOSURES: RESULTS FROM A POPULATION EXPOSURE MODEL FOR PHILADELPHIA, PA

EPA Science Inventory

The US EPA National Exposure Research Laboratory (NERL) is currently developing an integrated human exposure source-to-dose modeling system (HES2D). This modeling system will incorporate population exposure modules that use a probabilistic approach to predict population exposu...

Population-Level Exposure to Particulate Air Pollution during Active Travel: Planning for Low-Exposure, Health-Promoting Cities

PubMed Central

Hankey, Steve; Lindsey, Greg; Marshall, Julian D.

2016-01-01

Background: Providing infrastructure and land uses to encourage active travel (i.e., bicycling and walking) are promising strategies for designing health-promoting cities. Population-level exposure to air pollution during active travel is understudied. Objectives: Our goals were a) to investigate population-level patterns in exposure during active travel, based on spatial estimates of bicycle traffic, pedestrian traffic, and particulate concentrations; and b) to assess how those exposure patterns are associated with the built environment. Methods: We employed facility–demand models (active travel) and land use regression models (particulate concentrations) to estimate block-level (n = 13,604) exposure during rush-hour (1600–1800 hours) in Minneapolis, Minnesota. We used the model-derived estimates to identify land use patterns and characteristics of the street network that are health promoting. We also assessed how exposure is correlated with indicators of health disparities (e.g., household income, proportion of nonwhite residents). Our work uses population-level rates of active travel (i.e., traffic flows) rather than the probability of walking or biking (i.e., “walkability” or “bikeability”) to assess exposure. Results: Active travel often occurs on high-traffic streets or near activity centers where particulate concentrations are highest (i.e., 20–42% of active travel occurs on blocks with high population-level exposure). Only 2–3% of blocks (3–8% of total active travel) are “sweet spots” (i.e., high active travel, low particulate concentrations); sweet spots are located a) near but slightly removed from the city-center or b) on off-street trails. We identified 1,721 blocks (~ 20% of local roads) where shifting active travel from high-traffic roads to adjacent low-traffic roads would reduce exposure by ~ 15%. Active travel is correlated with population density, land use mix, open space, and retail area; particulate concentrations were

Use of population exposure frequency distributions to simulate effects of policy interventions on NO2 exposure

NASA Astrophysics Data System (ADS)

Dimitroulopoulou, C.; Ashmore, M. R.; Terry, A. C.

2017-02-01

Health effects of air pollution on individuals depend on their personal exposure, but few modelling tools are available which can predict how the distribution of personal exposures within a city will change in response to policies to reduce emissions both indoors and outdoors. We describe a new probabilistic modelling framework (INDAIR-2/EXPAIR), which provides predictions of the personal exposure frequency distribution (PEFD) across a city to assess the effects of both reduced emissions from home sources and reduced roadside concentrations on population exposure. The model uses a national time activity database, which gives the percentage of each population group in different residential and non-residential micro-environments, and links this, for the home, to predictions of concentrations from a three-compartment model, and for non-residential microenvironments to empirical indoor/outdoor ratios. This paper presents modelled PEFDs for NO2 in the city of Leicester, for children, the elderly, and office workers, comparing results in different seasons and on different days of the week. While the mean NO2 population exposure was close to, or below the urban background concentration, the 95%ile of the PEFD was well above the urban background concentration. The relationship between both mean and 95%ile PEFD and urban background concentrations was strongly influenced by air exchange rate. The 24 h mean PEFD showed relative small differences between the population groups, with both removal of home sources and reductions of roadside concentrations on roads with a high traffic density having similar effects in reducing mean exposure. In contrast, the 1 h maximum of the PEFD was significantly higher for children and the elderly than for office workers, and showed a much greater response to reduced home emissions in these groups. The results demonstrate the importance of understanding the dynamics of NO2 exposure at a population level within different groups, if the benefits

Population-Based Assessment of Exposure to Risk Behaviors in Motion Pictures

PubMed Central

Sargent, James D.; Worth, Keilah A.; Beach, Michael; Gerrard, Meg; Heatherton, Todd F.

2008-01-01

The aim of most population-based studies of media is to relate a specific exposure to an outcome of interest. A research program has been developed that evaluates exposure to different components of movies in an attempt of assess the association of such exposure with the adoption of substance use during adolescence. To assess exposure to movie substance use, one must measure both viewing time and content. In developing the exposure measure, the study team was interested in circumventing a common problem in exposure measurement, where measures often conflate exposure to media with attention to media. Our aim in this paper is to present a validated measure of exposure to entertainment media, the Beach method, which combines recognition of a movie title with content analysis of the movie for substance use, to generate population based measures of exposure to substance use in this form of entertainment. PMID:19122801

Population-Based Assessment of Exposure to Risk Behaviors in Motion Pictures.

PubMed

Sargent, James D; Worth, Keilah A; Beach, Michael; Gerrard, Meg; Heatherton, Todd F

2008-01-01

The aim of most population-based studies of media is to relate a specific exposure to an outcome of interest. A research program has been developed that evaluates exposure to different components of movies in an attempt of assess the association of such exposure with the adoption of substance use during adolescence. To assess exposure to movie substance use, one must measure both viewing time and content. In developing the exposure measure, the study team was interested in circumventing a common problem in exposure measurement, where measures often conflate exposure to media with attention to media. Our aim in this paper is to present a validated measure of exposure to entertainment media, the Beach method, which combines recognition of a movie title with content analysis of the movie for substance use, to generate population based measures of exposure to substance use in this form of entertainment.

Homework "Dose," Type, and Helpfulness as Predictors of Clinical Outcomes in Prolonged Exposure for PTSD.

PubMed

Cooper, Andrew A; Kline, Alexander C; Graham, Belinda; Bedard-Gilligan, Michele; Mello, Patricia G; Feeny, Norah C; Zoellner, Lori A

2017-03-01

Homework is often viewed as central to prolonged exposure (PE) for posttraumatic stress disorder (PTSD), but its relationship with treatment outcome is not well understood. We evaluated homework type, dose, and patients' perceptions of helpfulness as predictors of symptom change and posttreatment outcomes in PE. Patients with chronic PTSD received PE in a randomized clinical trial. Independent evaluators assessed PTSD severity at pre- and posttreatment. Patients reported homework adherence and perceived helpfulness at the beginning of each session, separately for in vivo and imaginal exposure assignments. These variables were examined as predictors of change in PTSD symptoms, PTSD remission, and good end-state functioning (GESF; low PTSD, depression, and anxiety) at posttreatment. Higher imaginal homework adherence predicted greater symptom improvement between sessions and across treatment, as well as twice the odds of achieving remission and GESF. Patients who were at least moderately adherent to imaginal homework assignments (two or more times a week) reported more symptom gains than those who were least adherent but did not differ from those who were most adherent. In vivo adherence was not consistently associated with better outcome, perhaps due to heterogeneity in form and function of weekly assignments. Higher ratings of helpfulness of both types of homework predicted greater symptom improvement from pre- to posttreatment and between sessions. Overall, imaginal exposure homework may complement in-session exposures by enhancing key change processes, though perfect adherence is not necessary. Patients' perceptions of helpfulness may reflect buy-in or perceived match between homework completion and functional impairment. Clinically, in addition to targeting adherence to homework assignments, querying about perceived helpfulness and adjusting assignments appropriately may help augment clinical gains. Copyright © 2016. Published by Elsevier Ltd.

Prolonged restraint stressor exposure in outbred CD-1 mice impacts microbiota, colonic inflammation, and short chain fatty acids.

PubMed

Maltz, Ross M; Keirsey, Jeremy; Kim, Sandra C; Mackos, Amy R; Gharaibeh, Raad Z; Moore, Cathy C; Xu, Jinyu; Bakthavatchalu, Vasudevan; Somogyi, Arpad; Bailey, Michael T

2018-01-01

Stressor-exposure has been shown to exacerbate inflammation and change the composition of the gastrointestinal microbiota; however stressor-induced effects on microbiota-derived metabolites and their receptors are unknown. Thus, bacterial-produced short chain fatty acids (SCFAs), as well as microbial community composition, were assessed in the colons of mice exposed to stress during infection with Citrobacter rodentium. Mice were exposed to overnight restraint on 7 consecutive nights, or left undisturbed as a control. After the first exposure of restraint, mice were orally challenged with C. rodentium or with vehicle. Microbial community composition was assessed using 16S rRNA gene sequencing and SCFA levels measured using gas chromatography-mass spectrometry (GC-MS). Pathogen levels and colonic inflammation were also assessed 6 days post-infection. Results demonstrated that the microbial community structure and SCFA production were significantly affected by both stressor exposure and C. rodentium-infection. Exposure to prolonged restraint in the absence of infection significantly reduced SCFAs (acetic acid, butyric acid, and propionic acid). Multiple bacterial taxa were affected by stressor exposure, with the relative abundance of Lactobacillus being significantly reduced and directly correlated with propionic acid. Lactobacillus abundances were inversely correlated with colonic inflammation, supporting the contention that Lactobacillus helps to regulate mucosal inflammatory responses. Our data indicates that restraint stressor can have significant effects on pathogen-induced colonic inflammation and suggest that stressor-induced changes in the microbiota, microbial-produced SCFAs and their receptors may be involved.

Population-Level Exposure to Particulate Air Pollution during Active Travel: Planning for Low-Exposure, Health-Promoting Cities.

PubMed

Hankey, Steve; Lindsey, Greg; Marshall, Julian D

2017-04-01

Providing infrastructure and land uses to encourage active travel (i.e., bicycling and walking) are promising strategies for designing health-promoting cities. Population-level exposure to air pollution during active travel is understudied. Our goals were a ) to investigate population-level patterns in exposure during active travel, based on spatial estimates of bicycle traffic, pedestrian traffic, and particulate concentrations; and b ) to assess how those exposure patterns are associated with the built environment. We employed facility-demand models (active travel) and land use regression models (particulate concentrations) to estimate block-level ( n = 13,604) exposure during rush-hour (1600-1800 hours) in Minneapolis, Minnesota. We used the model-derived estimates to identify land use patterns and characteristics of the street network that are health promoting. We also assessed how exposure is correlated with indicators of health disparities (e.g., household income, proportion of nonwhite residents). Our work uses population-level rates of active travel (i.e., traffic flows) rather than the probability of walking or biking (i.e., "walkability" or "bikeability") to assess exposure. Active travel often occurs on high-traffic streets or near activity centers where particulate concentrations are highest (i.e., 20-42% of active travel occurs on blocks with high population-level exposure). Only 2-3% of blocks (3-8% of total active travel) are "sweet spots" (i.e., high active travel, low particulate concentrations); sweet spots are located a ) near but slightly removed from the city-center or b ) on off-street trails. We identified 1,721 blocks (~ 20% of local roads) where shifting active travel from high-traffic roads to adjacent low-traffic roads would reduce exposure by ~ 15%. Active travel is correlated with population density, land use mix, open space, and retail area; particulate concentrations were mostly unchanged with land use. Public health officials and

Absence of acute ocular damage in humans after prolonged exposure to intense RF EMF

NASA Astrophysics Data System (ADS)

Adibzadeh, F.; van Rhoon, G. C.; Verduijn, G. M.; Naus-Postema, N. C.; Paulides, M. M.

2016-01-01

The eye is considered to be a critical organ when determining safety standards for radio frequency (RF) radiation. Experimental data obtained using animals showed that RF heating of the eye, particularly over a specific threshold, can induce cataracts. During the treatment of cancer in the head and neck by hyperthermia, the eyes receive a considerable dose of RF radiation due to stray radiation from the prolonged (60 min) and intense exposure at 434 MHz of this region. In the current study, we verified the exposure guidelines for humans by determining the association between the electromagnetic and thermal dose in the eyes with the reported ocular effects. We performed a simulation study to retrospectively assess the specific absorption rate (SAR) and temperature increase in the eyes of 16 selected patients (encompassing a total of 74 treatment sessions) whose treatment involved high power delivery as well as a minimal distance between the tumor site and the eye. Our results show that the basic restrictions on the peak 10 g spatial-averaged SAR (10 W kg-1) and peak tissue temperature increase (1 °C) are exceeded by up to 10.4 and 4.6 times, on average, and by at least 6.2 and 1.8 times when considering the lower limit of the 95% confidence interval. Evaluation of the acute effects according to patients’ feedback (all patients), the common toxicity criteria scores (all patients) and an ophthalmology investigation (one patient with the highest exposure) revealed no indication of any serious acute ocular effect, even though the eyes were exposed to high electromagnetic fields, leading to a high thermal dose. We also found that, although there is a strong correlation (R 2  =  0.88) between the predicted induced SAR and temperature in the eye, there are large uncertainties regarding the temperature-SAR relationship. Given this large uncertainty (129%) compared with the uncertainty of 3D temperature simulations (61%), we recommend using temperature

PREDICTING POPULATION EXPOSURES TO PM: THE IMPORTANCE OF MICROENVIRONMENTAL CONCENTRATIONS AND HUMAN ACTIVITIES

EPA Science Inventory

The Stochastic Human Exposure and Dose Simulation (SHEDS) models being developed by the US EPA/NERL use a probabilistic approach to predict population exposures to pollutants. The SHEDS model for particulate matter (SHEDS-PM) estimates the population distribution of PM exposure...

Piperaquine Population Pharmacokinetics and Cardiac Safety in Cambodia

PubMed Central

Lon, Chanthap; Spring, Michele; Sok, Sommethy; Ta-aksorn, Winita; Kodchakorn, Chanikarn; Pann, Sut-Thang; Chann, Soklyda; Ittiverakul, Mali; Sriwichai, Sabaithip; Buathong, Nillawan; Kuntawunginn, Worachet; So, Mary; Youdaline, Theng; Milner, Erin; Wojnarski, Mariusz; Lanteri, Charlotte; Manning, Jessica; Prom, Satharath; Haigney, Mark; Cantilena, Louis; Saunders, David

2017-01-01

ABSTRACT Despite the rising rates of resistance to dihydroartemisinin-piperaquine (DP), DP remains a first-line therapy for uncomplicated malaria in many parts of Cambodia. While DP is generally well tolerated as a 3-day DP (3DP) regimen, compressed 2-day DP (2DP) regimens were associated with treatment-limiting cardiac repolarization effects in a recent clinical trial. To better estimate the risks of piperaquine on QT interval prolongation, we pooled data from three randomized clinical trials conducted between 2010 and 2014 in northern Cambodia. A population pharmacokinetic model was developed to compare exposure-response relationships between the 2DP and 3DP regimens while accounting for differences in regimen and sample collection times between studies. A 2-compartment model with first-order absorption and elimination without covariates best fit the data. The linear slope-intercept model predicted a 0.05-ms QT prolongation per ng/ml of piperaquine (5 ms per 100 ng/ml) in this largely male population. Though the plasma half-life was similar in both regimens, peak and total piperaquine exposures were higher in those treated with the 2DP regimen. Furthermore, the correlation between the plasma piperaquine concentration and the QT interval prolongation was stronger in the population receiving the 2DP regimen. Neither the time since the previous meal nor the baseline serum magnesium or potassium levels had additive effects on QT interval prolongation. As electrocardiographic monitoring is often nonexistent in areas where malaria is endemic, 2DP regimens should be avoided and the 3DP regimen should be carefully considered in settings where viable alternative therapies exist. When DP is employed, the risk of cardiotoxicity can be mitigated by combining a 3-day regimen, enforcing a 3-h fast before and after administration, and avoiding the concomitant use of QT interval-prolonging medications. (This study used data from three clinical trials that are registered at

Osborn waves in severe accidental hypothermia secondary to prolonged immobilization and malnutrition.

PubMed

Rotondi, Francesco; Manganelli, Fiore; Candelmo, Fiore; Marino, Luciano; Di Lorenzo, Emilio; Alfano, Ferdinando; Stanco, Giovanni; Rosato, Giuseppe

2010-07-01

We report the case of a 77-year-old man, in whom accidental hypothermia was secondary to prolonged immobilization and malnutrition. The electrocardiogram showed typical Osborn waves, which disappeared with the rewarming of the patient. The diagnosis of hypothermia is easy in patients with a history of prolonged exposure to a cold environment but accidental hypothermia may also occur as a consequence of prolonged immobilization and malnutrition. ECG analysis is very important for a correct and fast diagnosis.

Exposure estimate for FD&C colour additives for the US population.

PubMed

Doell, Diana L; Folmer, Daniel E; Lee, Hyoung S; Butts, Kyla M; Carberry, Susan E

2016-05-01

Dietary exposures to the seven food, drug, and cosmetic (FD&C) colour additives that are approved for general use in food in the United States were estimated for the US population (aged 2 years and older), children (aged 2-5 years) and teenage boys (aged 13-18 years) based on analytical levels of the FD&C colour additives in foods. Approximately 600 foods were chosen for analysis, based on a survey of product labels, for the levels of FD&C colour additives. Dietary exposure was estimated using both 2-day food consumption data from the combined 2007-10 National Health and Nutrition Examination Survey (NHANES) and 10-14-day food consumption data from the 2007-10 NPD Group, Inc. National Eating Trends - Nutrient Intake Database (NPD NET-NID). Dietary exposure was estimated at the mean and 90th percentile using three different exposure scenarios: low exposure, average exposure and high exposure, to account for the range in the amount of each FD&C colour additive for a given food. For all populations and all exposure scenarios, the highest cumulative eaters-only exposures in food were determined for FD&C Red No. 40, FD&C Yellow No. 5 and FD&C Yellow No. 6. In addition, the eaters-only exposure was estimated for individual food categories in order to determine which food categories contributed the most to the exposure for each FD&C colour additive. Breakfast Cereal, Juice Drinks, Soft Drinks, and Frozen Dairy Desserts/Sherbet (also referred to as Ice Cream, Frozen Yogurt, Sherbet (including Bars, Sticks, Sandwiches)) were the major contributing food categories to exposure for multiple FD&C colour additives for all three populations.

Is Exposure Necessary? A Randomized Clinical Trial of Interpersonal Psychotherapy for PTSD

PubMed Central

Markowitz, John C.; Petkova, Eva; Neria, Yuval; Van Meter, Page E.; Zhao, Yihong; Hembree, Elizabeth; Lovell, Karina; Biyanova, Tatyana; Marshall, Randall D.

2015-01-01

Background Exposure to trauma reminders has been considered imperative in psychotherapy for posttraumatic stress disorder (PTSD). No treatment benefits all patients, however. We tested Interpersonal Psychotherapy, which has demonstrated antidepressant efficacy and showed promise in pilot PTSD research, as a non-exposure-based, non-cognitive behavioral PTSD treatment. Methods A randomized, fourteen-week trial compared Interpersonal Psychotherapy; Prolonged Exposure, an exposure-based exemplar; and Relaxation Therapy, an active control psychotherapy. Subjects were 110 unmedicated patients having DSM-IV chronic PTSD and Clinician-Administered PTSD Scale (CAPS) score >50. Randomization stratified for comorbid major depression. We hypothesized Interpersonal Psychotherapy would be no more than minimally inferior (CAPS difference <12.5 points) to Prolonged Exposure. Results All therapies had large within-group pre/post effect sizes (d=1.32–1.88). Response rates (>30% CAPS improvement) were: Interpersonal Psychotherapy 63%, Prolonged Exposure 47%, Relaxation Therapy 38% (n.s.). Interpersonal psychotherapy and Prolonged Exposure CAPS outcome differed by 5.5 points (n.s.); the null hypothesis of more than minimal Interpersonal Psychotherapy inferiority was rejected (p=0.035). Patients with comorbid major depression dropped out from Prolonged Exposure nine times more than non-depressed Prolonged Exposure patients. Interpersonal Psychotherapy and Prolonged Exposure improved quality of life and social functioning more than Relaxation Therapy. Conclusions This first controlled study of individual Interpersonal Psychotherapy for PTSD demonstrated non-inferiority to the “gold standard” PTSD treatment. Interpersonal Psychotherapy had (non-significantly) lower attrition and higher response rates than Prolonged Exposure. Contradicting a widespread clinical belief, PTSD treatment may not require cognitive behavioral exposure to trauma reminders. Moreover, as differential

Lead exposure in Canada geese of the Eastern Prairie Population

USGS Publications Warehouse

DeStefano, S.; Brand, C.J.; Rusch, D.H.; Finley, Daniel L.; Gillespie, M.M.

1991-01-01

We monitored lead exposure in Eastern Prairie Population Canada geese during summer-winter, 1986-1987 and 1987-1988 at 5 areas. Blood lead concentrations in geese trapped during summer at Cape Churchill Manitoba were below levels indicative of recent lead exposure (0.18 ppm). Geese exposed to lead (≥0.18 ppm blood lead) increased to 7.6% at Oak Hammock Wildlife Management Area (WMA), southern Manitoba, where lead shot was still in use, and to 10.0% at Roseau River WMA, northern Minnesota, when fall-staging geese were close to a source of lead shot in Manitoba. Proportion of birds exposed to lead dropped to <2% at Lac Qui Parle WMA, Minnesota, a steel shot zone since 1980. On the wintering grounds at Swan Lake National Wildlife Refuge in Missouri, 4.9% of all geese showed exposure to lead before the hunting season. Lead exposure rose to 10.0% after hunting ended and then decreased to 5.2% in late winter. Incidence of lead shot in gizzards and concentrations of lead in livers supported blood assay data. Soil samples indicated that lead shot continues to be available to geese at Swan Lake, even though the area was established as a non-toxic shot zone in 1978. Steel shot zones have reduced lead exposure in the Eastern Prairie Population, but lead shot persists in the environment and continues to account for lead exposure and mortality in Eastern Prairie Population Canada geese.

Exposure estimate for FD&C colour additives for the US population

PubMed Central

Folmer, Daniel E.; Lee, Hyoung S.; Butts, Kyla M.; Carberry, Susan E.

2016-01-01

Dietary exposures to the seven food, drug, and cosmetic (FD&C) colour additives that are approved for general use in food in the United States were estimated for the US population (aged 2 years and older), children (aged 2–5 years) and teenage boys (aged 13–18 years) based on analytical levels of the FD&C colour additives in foods. Approximately 600 foods were chosen for analysis, based on a survey of product labels, for the levels of FD&C colour additives. Dietary exposure was estimated using both 2-day food consumption data from the combined 2007–10 National Health and Nutrition Examination Survey (NHANES) and 10–14-day food consumption data from the 2007–10 NPD Group, Inc. National Eating Trends – Nutrient Intake Database (NPD NET-NID). Dietary exposure was estimated at the mean and 90th percentile using three different exposure scenarios: low exposure, average exposure and high exposure, to account for the range in the amount of each FD&C colour additive for a given food. For all populations and all exposure scenarios, the highest cumulative eaters-only exposures in food were determined for FD&C Red No. 40, FD&C Yellow No. 5 and FD&C Yellow No. 6. In addition, the eaters-only exposure was estimated for individual food categories in order to determine which food categories contributed the most to the exposure for each FD&C colour additive. Breakfast Cereal, Juice Drinks, Soft Drinks, and Frozen Dairy Desserts/Sherbet (also referred to as Ice Cream, Frozen Yogurt, Sherbet (including Bars, Sticks, Sandwiches)) were the major contributing food categories to exposure for multiple FD&C colour additives for all three populations. PMID:27092991

APPROACHES TO ECOSYSTEM AND HUMAN EXPOSURE TO MERCURY FOR SENSITIVE POPULATIONS

EPA Science Inventory

Both human and ecosystem exposure studies evaluate exposure of sensitive and vulnerable populations. We will discuss how ecosystem exposure modeling studies completed for input into the US Clean Air Mercury Rule (CAMR) to evaluate the response of aquatic ecosystems to changes in ...

Bisphenol A Exposure and Cardiac Electrical Conduction in Excised Rat Hearts

PubMed Central

Jaimes, Rafael; Asfour, Huda; Swift, Luther M.; Wengrowski, Anastasia M.; Sarvazyan, Narine; Kay, Matthew W.

2014-01-01

Background: Bisphenol A (BPA) is used to produce polycarbonate plastics and epoxy resins that are widely used in everyday products, such as food and beverage containers, toys, and medical devices. Human biomonitoring studies have suggested that a large proportion of the population may be exposed to BPA. Recent epidemiological studies have reported correlations between increased urinary BPA concentrations and cardiovascular disease, yet the direct effects of BPA on the heart are unknown. Objectives: The goal of our study was to measure the effect of BPA (0.1–100 μM) on cardiac impulse propagation ex vivo using excised whole hearts from adult female rats. Methods: We measured atrial and ventricular activation times during sinus and paced rhythms using epicardial electrodes and optical mapping of transmembrane potential in excised rat hearts exposed to BPA via perfusate media. Atrioventricular activation intervals and epicardial conduction velocities were computed using recorded activation times. Results: Cardiac BPA exposure resulted in prolonged PR segment and decreased epicardial conduction velocity (0.1–100 μM BPA), prolonged action potential duration (1–100 μM BPA), and delayed atrioventricular conduction (10–100 μM BPA). These effects were observed after acute exposure (≤ 15 min), underscoring the potential detrimental effects of continuous BPA exposure. The highest BPA concentration used (100 μM) resulted in prolonged QRS intervals and dropped ventricular beats, and eventually resulted in complete heart block. Conclusions: Our results show that acute BPA exposure slowed electrical conduction in excised hearts from female rats. These findings emphasize the importance of examining BPA’s effect on heart electrophysiology and determining whether chronic in vivo exposure can cause or exacerbate conduction abnormalities in patients with preexisting heart conditions and in other high-risk populations. Citation: Posnack NG, Jaimes R III, Asfour H

PM2.5 Population Exposure in New Delhi Using a Probabilistic Simulation Framework.

PubMed

Saraswat, Arvind; Kandlikar, Milind; Brauer, Michael; Srivastava, Arun

2016-03-15

This paper presents a Geographical Information System (GIS) based probabilistic simulation framework to estimate PM2.5 population exposure in New Delhi, India. The framework integrates PM2.5 output from spatiotemporal LUR models and trip distribution data using a Gravity model based on zonal data for population, employment and enrollment in educational institutions. Time-activity patterns were derived from a survey of randomly sampled individuals (n = 1012) and in-vehicle exposure was estimated using microenvironmental monitoring data based on field measurements. We simulated population exposure for three different scenarios to capture stay-at-home populations (Scenario 1), working population exposed to near-road concentrations during commutes (Scenario 2), and the working population exposed to on-road concentrations during commutes (Scenario 3). Simulated annual average levels of PM2.5 exposure across the entire city were very high, and particularly severe in the winter months: ∼200 μg m(-3) in November, roughly four times higher compared to the lower levels in the monsoon season. Mean annual exposures ranged from 109 μg m(-3) (IQR: 97-120 μg m(-3)) for Scenario 1, to 121 μg m(-3) (IQR: 110-131 μg m(-3)), and 125 μg m(-3) (IQR: 114-136 μ gm(-3)) for Scenarios 2 and 3 respectively. Ignoring the effects of mobility causes the average annual PM2.5 population exposure to be underestimated by only 11%.

Competing for Consciousness: Prolonged Mask Exposure Reduces Object Substitution Masking

ERIC Educational Resources Information Center

Goodhew, Stephanie C.; Visser, Troy A. W.; Lipp, Ottmar V.; Dux, Paul E.

2011-01-01

In object substitution masking (OSM) a sparse, temporally trailing 4-dot mask impairs target identification, even though it has different contours from, and does not spatially overlap with the target. Here, we demonstrate a previously unknown characteristic of OSM: Observers show reduced masking at prolonged (e.g., 640 ms) relative to intermediate…

Training in the implementation of prolonged exposure therapy: provider correlates of treatment outcome.

PubMed

Eftekhari, Afsoon; Crowley, Jill J; Ruzek, Josef I; Garvert, Donn W; Karlin, Bradley E; Rosen, Craig S

2015-02-01

The authors examined the degree to which provider characteristics, such as profession, treatment orientation, prior experience in treating posttraumatic stress disorder (PTSD), prior experience with prolonged exposure (PE) therapy, and attitudes about PE, were related to the clinical outcomes of veterans receiving care from clinicians participating in the national Department of Veterans Affairs (VA) PE Training Program. Positive patient outcomes were achieved by providers of every profession, theoretical orientation, level of clinical experience treating PTSD, and prior PE training experience. With 1,105 providers and 32 predictors (13 provider variables), power was at least 90% power to detect an effect of β = .15. Profession was the only provider characteristic significantly related to outcomes, but the mean effect (a 2 point difference on the PTSD Checklist) was too small to be clinically meaningful. The results support the intensive training model used in the VA PE training program and demonstrate that clinicians of varying backgrounds can be trained using interactive training workshops followed by case consultation to deliver PE effectively. Published 2015. This article is a US Government work and is in the public domain in the USA.

Assessment of population exposure to particulate matter pollution in Chongqing, China.

PubMed

Wang, Shuxiao; Zhao, Yu; Chen, Gangcai; Wang, Fei; Aunan, Kristin; Hao, Jiming

2008-05-01

To determine the population exposure to PM(10) in Chongqing, China, we developed an indirect model by combining information on the time activity patterns of various demographic subgroups with estimates of the PM(10) concentrations in different microenvironments (MEs). The spatial and temporal variations of the exposure to PM(10) were illustrated in a geographical information system (GIS). The population weighted exposure (PWE) for the entire population was 229, 155 and 211 microg/m(3), respectively, in winter, summer and as the annual average. Indoor PM(10) level at home was the largest contributor to the PWE, especially for the rural areas where high pollution levels were found due to solid fuels burning. Elder people had higher PM(10) exposure than adults and youth, due to more time spent in indoor MEs. The highest health risk due to particulate was found in the city zone and northeast regions, suggesting that pollution abatement should be prioritized in these areas.

Calcium, magnesium, and phosphorus metabolism, and parathyroid-calcitonin function during prolonged exposure to elevated CO2 concentrations on submarines.

PubMed

Messier, A A; Heyder, E; Braithwaite, W R; McCluggage, C; Peck, A; Schaefer, K E

1979-01-01

Studies of calcium and phosphorus metabolism and acid-base balance were carried out on three Fleet Ballistic Missile (FBM) submarines during prolonged exposure to elevated concentrations of CO2. The average CO2 concentration in the submarine atmosphere during patrols ranged from 0.85% to 1% CO2. In the three studies, in which 9--15 subjects participated, the urinary excretion of calcium and phosphate fell during the first three weeks to a level commensurate with a decrease in plasma calcium and increase in phosphorus. In the fourth week of one patrol, a marked increase was found in urinary calcium excretion, associated with a rise in blood PCO2 and bicarbonate. Urinary calcium excretion decreased again during the 5th to 8th week, with a secondary decrease in blood pH and plasma calcium. During the third patrol, the time course of acid-base changes corresponded well with that found during the second patrol. There was a trend toward an increase in plasma calcium between the fourth and fifth week commensurate with the transient rise in pH and bicarbonate. Plasma parathyroid and calcitonin hormone activities were measured in two patrols and no significant changes were found. Hydroxyproline excretion decreased in the three-week study and remained unchanged in the second patrol, which lasted 57 days. It is suggested that during prolonged exposure to low levels of CO2 (up to 1% CO2), calcium metabolism is controlled by the uptake and release of CO2 in the bones. The resulting phases in bone buffering, rather than renal regulation, determine acid-base balance.

POPULATION EXPOSURE AND DOSE MODEL FOR AIR TOXICS: A BENZENE CASE STUDY

EPA Science Inventory

The EPA's National Exposure Research Laboratory (NERL) is developing a human exposure and dose model called the Stochastic Human Exposure and Dose Simulation model for Air Toxics (SHEDS-AirToxics) to characterize population exposure to air toxics in support of the National Air ...

Prolonged exposure to WIN55,212-2 causes down-regulation of the CB1 receptor and the development of tolerance to its anticonvulsant effects in the hippocampal neuronal culture model of acquired epilepsy

PubMed Central

Blair, Robert E.; Deshpande, Laxmikant S.; Sombati, Sompong; Elphick, Maurice R.; Martin, Billy R.; DeLorenzo, Robert J.

2009-01-01

Summary Cannabinoids have been shown to cause CB1-receptor dependent anticonvulsant activity in both in vivo and in vitro models of status epilepticus (SE) and acquired epilepsy (AE). It has been further demonstrated in these models that the endocannabinoid system functions in a tonic manner to suppress seizure discharges through a CB1-receptor dependent pathway. Although acute cannabinoid treatment has anticonvulsant activity, little is known concerning the effects of prolonged exposure to CB1 agonists and development of tolerance on the epileptic phenotype. This study was carried out to evaluate the effects of prolonged exposure to the CB1 agonist WIN55,212-2 on seizure activity in a hippocampal neuronal culture model of low-Mg2+ induced spontaneous recurrent epileptiform discharges (SREDs). Following low-Mg2+ induced SREDs, cultures were returned to maintenance media containing 10, 100 or 1000 nM WIN55,212-2 from 4 to 24 hours. Whole-cell current-clamp analysis of WIN55,212-2 treated cultures revealed a concentration-dependent increase in SRED frequency. Immunocytochemical staining revealed that WIN55,212-2 treatment induced a concentration-dependent down-regulation of the CB1 receptor in neuronal processes and at both glutamatergic and GABAergic presynaptic terminals. Prolonged exposure to the inactive enantiomer WIN55,212-3 in low-Mg2+ treated cultures had no effect on the frequency of SREDs or CB1 receptor staining. The results from this study further substantiate a role for a tonic CB1 receptor-dependent endocannabinoid regulation of seizure discharge and suggest that prolonged exposure to cannabinoids results in the development of tolerance to the anticonvulsant effects of cannabinoids and an exacerbation of seizure activity in the epileptic phenotype. PMID:19540252

Epidemic gasoline exposures following Hurricane Sandy.

PubMed

Kim, Hong K; Takematsu, Mai; Biary, Rana; Williams, Nicholas; Hoffman, Robert S; Smith, Silas W

2013-12-01

Major adverse climatic events (MACEs) in heavily-populated areas can inflict severe damage to infrastructure, disrupting essential municipal and commercial services. Compromised health care delivery systems and limited utilities such as electricity, heating, potable water, sanitation, and housing, place populations in disaster areas at risk of toxic exposures. Hurricane Sandy made landfall on October 29, 2012 and caused severe infrastructure damage in heavily-populated areas. The prolonged electrical outage and damage to oil refineries caused a gasoline shortage and rationing unseen in the USA since the 1970s. This study explored gasoline exposures and clinical outcomes in the aftermath of Hurricane Sandy. Prospectively collected, regional poison control center (PCC) data regarding gasoline exposure cases from October 29, 2012 (hurricane landfall) through November 28, 2012 were reviewed and compared to the previous four years. The trends of gasoline exposures, exposure type, severity of clinical outcome, and hospital referral rates were assessed. Two-hundred and eighty-three gasoline exposures were identified, representing an 18 to 283-fold increase over the previous four years. The leading exposure route was siphoning (53.4%). Men comprised 83.0% of exposures; 91.9% were older than 20 years of age. Of 273 home-based calls, 88.7% were managed on site. Asymptomatic exposures occurred in 61.5% of the cases. However, minor and moderate toxic effects occurred in 12.4% and 3.5% of cases, respectively. Gastrointestinal (24.4%) and pulmonary (8.4%) symptoms predominated. No major outcomes or deaths were reported. Hurricane Sandy significantly increased gasoline exposures. While the majority of exposures were managed at home with minimum clinical toxicity, some patients experienced more severe symptoms. Disaster plans should incorporate public health messaging and regional PCCs for public health promotion and toxicological surveillance.

Influence of internal variability on population exposure to hydroclimatic changes

NASA Astrophysics Data System (ADS)

Mankin, Justin S.; Viviroli, Daniel; Mekonnen, Mesfin M.; Hoekstra, Arjen Y.; Horton, Radley M.; E Smerdon, Jason; Diffenbaugh, Noah S.

2017-04-01

Future freshwater supply, human water demand, and people’s exposure to water stress are subject to multiple sources of uncertainty, including unknown future pathways of fossil fuel and water consumption, and ‘irreducible’ uncertainty arising from internal climate system variability. Such internal variability can conceal forced hydroclimatic changes on multi-decadal timescales and near-continental spatial-scales. Using three projections of population growth, a large ensemble from a single Earth system model, and assuming stationary per capita water consumption, we quantify the likelihoods of future population exposure to increased hydroclimatic deficits, which we define as the average duration and magnitude by which evapotranspiration exceeds precipitation in a basin. We calculate that by 2060, ∽31%-35% of the global population will be exposed to >50% probability of hydroclimatic deficit increases that exceed existing hydrological storage, with up to 9% of people exposed to >90% probability. However, internal variability, which is an irreducible uncertainty in climate model predictions that is under-sampled in water resource projections, creates substantial uncertainty in predicted exposure: ∽86%-91% of people will reside where irreducible uncertainty spans the potential for both increases and decreases in sub-annual water deficits. In one population scenario, changes in exposure to large hydroclimate deficits vary from -3% to +6% of global population, a range arising entirely from internal variability. The uncertainty in risk arising from irreducible uncertainty in the precise pattern of hydroclimatic change, which is typically conflated with other uncertainties in projections, is critical for climate risk management that seeks to optimize adaptations that are robust to the full set of potential real-world outcomes.

A dynamic urban air pollution population exposure assessment study using model and population density data derived by mobile phone traffic

NASA Astrophysics Data System (ADS)

Gariazzo, Claudio; Pelliccioni, Armando; Bolignano, Andrea

2016-04-01

A dynamic city-wide air pollution exposure assessment study has been carried out for the urban population of Rome, Italy, by using time resolved population distribution maps, derived by mobile phone traffic data, and modelled air pollutants (NO2, O3 and PM2.5) concentrations obtained by an integrated air dispersion modelling system. More than a million of persons were tracked during two months (March and April 2015) for their position within the city and its surroundings areas, with a time resolution of 15 min and mapped over an irregular grid system with a minimum resolution of 0.26 × 0.34 Km2. In addition, demographics information (as gender and age ranges) were available in a separated dataset not connected with the total population one. Such BigData were matched in time and space with air pollution model results and then used to produce hourly and daily resolved cumulative population exposures during the studied period. A significant mobility of population was identified with higher population densities in downtown areas during daytime increasing of up to 1000 people/Km2 with respect to nigh-time one, likely produced by commuters, tourists and working age population. Strong variability (up to ±50% for NO2) of population exposures were detected as an effect of both mobility and time/spatial changing in pollutants concentrations. A comparison with the correspondent stationary approach based on National Census data, allows detecting the inability of latter in estimating the actual variability of population exposure. Significant underestimations of the amount of population exposed to daily PM2.5 WHO guideline was identified for the Census approach. Very small differences (up to a few μg/m3) on exposure were detected for gender and age ranges population classes.

Dietary exposure to acrylamide from potato crisps to the Spanish population.

PubMed

Arribas-Lorenzo, G; Morales, F J

2009-03-01

Potato crisps are one of the food commodities that contribute most to overall dietary human exposure of acrylamide. This investigation has estimated the dietary exposure to acrylamide form potato crisps in the Spanish population. Sampling of potato crisps (n = 36) from 16 different producers were carried out in March 2008. An average level of 740 microg kg(-1) (ranging from 81 to 2622 microg kg(-1); minimum to maximum) and a median of 592 microg kg(-1) were obtained. Acrylamide levels in marketed potato crisps have been significantly reduced (nearly to 50%) compared with a previous sampling performed 4 years earlier. The observed signal value (90th percentile) was 1377 microg kg(-1) with 86% of the samples with acrylamide levels lower than 1000 microg kg(-1). Dietary exposure to acrylamide from potato crisp consumption in the total Spanish population was estimated to be 0.042 microg kg(-1) body weight day(-1) by using a deterministic approach based on the National consumption database. In a second study, dietary exposure (based on a 3-day food record) was determined to be 0.053 microg kg(-1) body weight day(-1) for the adult population (17-60 years) and 0.142 microg kg(-1) body weight day(-1) for children (7-12 years). The contribution of potato crisps to the estimated dietary acrylamide exposure of the Spanish population is moderate as compared with other European Member States.

Combining a Job-Exposure Matrix with Exposure Measurements to Assess Occupational Exposure to Benzene in a Population Cohort in Shanghai, China

PubMed Central

Friesen, Melissa C.; Coble, Joseph B.; Lu, Wei; Shu, Xiao-Ou; Ji, Bu-Tian; Xue, Shouzheng; Portengen, Lutzen; Chow, Wong-Ho; Gao, Yu-Tang; Yang, Gong; Rothman, Nathaniel; Vermeulen, Roel

2012-01-01

Background: Generic job-exposure matrices (JEMs) are often used in population-based epidemiologic studies to assess occupational risk factors when only the job and industry information of each subject is available. JEM ratings are often based on professional judgment, are usually ordinal or semi-quantitative, and often do not account for changes in exposure over time. We present an empirical Bayesian framework that combines ordinal subjective JEM ratings with benzene measurements. Our aim was to better discriminate between job, industry, and time differences in exposure levels compared to using a JEM alone. Methods: We combined 63 221 short-term area air measurements of benzene exposure (1954–2000) collected during routine health and safety inspections in Shanghai, China, with independently developed JEM intensity ratings for each job and industry using a mixed-effects model. The fixed-effects terms included the JEM intensity ratings for job and industry (both ordinal, 0–3) and a time trend that we incorporated as a b-spline. The random-effects terms included job (n = 33) and industry nested within job (n = 399). We predicted the benzene concentration in two ways: (i) a calibrated JEM estimate was calculated using the fixed-effects model parameters for calendar year and JEM intensity ratings; (ii) a job-/industry-specific estimate was calculated using the fixed-effects model parameters and the best linear unbiased predictors from the random effects for job and industry using an empirical Bayes estimation procedure. Finally, we applied the predicted benzene exposures to a prospective population-based cohort of women in Shanghai, China (n = 74 942). Results: Exposure levels were 13 times higher in 1965 than in 2000 and declined at a rate that varied from 4 to 15% per year from 1965 to 1985, followed by a small peak in the mid-1990s. The job-/industry-specific estimates had greater differences between exposure levels than the calibrated JEM estimates (97.5th

Dynamic assessments of population exposure to urban greenspace using multi-source big data.

PubMed

Song, Yimeng; Huang, Bo; Cai, Jixuan; Chen, Bin

2018-09-01

A growing body of evidence has proven that urban greenspace is beneficial to improve people's physical and mental health. However, knowledge of population exposure to urban greenspace across different spatiotemporal scales remains unclear. Moreover, the majority of existing environmental assessments are unable to quantify how residents enjoy their ambient greenspace during their daily life. To deal with this challenge, we proposed a dynamic method to assess urban greenspace exposure with the integration of mobile-phone locating-request (MPL) data and high-spatial-resolution remote sensing images. This method was further applied to 30 major cities in China by assessing cities' dynamic greenspace exposure levels based on residents' surrounding areas with different buffer scales (0.5km, 1km, and 1.5km). Results showed that regarding residents' 0.5-km surrounding environment, Wenzhou and Hangzhou were found to be with the greenest exposure experience, whereas Zhengzhou and Tangshan were the least ones. The obvious diurnal and daily variations of population exposure to their surrounding greenspace were also identified to be highly correlated with the distribution pattern of urban greenspace and the dynamics of human mobility. Compared with two common measurements of urban greenspace (green coverage rate and green area per capita), the developed method integrated the dynamics of population distribution and geographic locations of urban greenspace into the exposure assessment, thereby presenting a more reasonable way to assess population exposure to urban greenspace. Additionally, this dynamic framework could hold potential utilities in supporting urban planning studies and environmental health studies and advancing our understanding of the magnitude of population exposure to greenspace at different spatiotemporal scales. Copyright © 2018 Elsevier B.V. All rights reserved.

Risk assessment of dietary exposure to aluminium in the Chinese population.

PubMed

Ma, Ning; Liu, Zhao-Ping; Yang, Da-Jin; Liang, Jiang; Zhu, Jiang-Hui; Xu, Hai-Bin; Li, Feng-Qin; Li, Ning

2016-10-01

In order to address the issue of excessive intake of aluminium (Al) from Al-containing food additives in the Chinese diet, this study conducted a dietary exposure assessment of Al in the general population based on the national surveillance data of Al content in foods and national food consumption data. It was found that the mean dietary exposure of the whole Chinese population to Al from Al-containing food additives was 1.795 mg kg ‒1 bw week ‒1 , not exceeding the PTWI, while high dietary exposures (e.g., 97.5 th percentile) to Al were 7.660 and 2.103-2.903 mg kg ‒1 bw week ‒1 for children, respectively, both exceeding the PTWI. It was found that the dietary exposure to Al for 32.5% of the total Chinese population and 42.6% of children aged 4-6 years exceeded the PTWI. Wheat flour and wheat-based products are the main source of dietary A l exposure (85% of the total intake); and puffed foods are the major source of Al intake for children. These findings suggested that consumption of Al-containing food additives could be a health concern for consumers with high food consumption (97.5 th percentile) and children under the age of 14 years.

Pattern of Change in Prolonged Exposure and Cognitive-Processing Therapy for Female Rape Victims With Posttraumatic Stress Disorder

PubMed Central

Nishith, Pallavi; Resick, Patricia A.; Griffin, Michael G.

2010-01-01

Curve estimation techniques were used to identify the pattern of therapeutic change in female rape victims with posttraumatic stress disorder (PTSD). Within-session data on the Posttraumatic Stress Disorder Symptom Scale were obtained, in alternate therapy sessions, on 171 women. The final sample of treatment completers included 54 prolonged exposure (PE) and 54 cognitive-processing therapy (CPT) completers. For both PE and CPT, a quadratic function provided the best fit for the total PTSD, reexperiencing, and arousal scores. However, a difference in the line of best fit was observed for the avoidance symptoms. Although a quadratic function still provided a better fit for the PE avoidance, a linear function was more parsimonious in explaining the CPT avoidance variance. Implications of the findings are discussed. PMID:12182271

Measuring Lead Exposure in Infants, Children, and Other Sensitive Populations.

ERIC Educational Resources Information Center

National Academy of Sciences - National Research Council, Washington, DC.

Adverse health effects from exposure to lead are now recognized to be among industrialized society's most important health problems. This report, prepared by the National Research Council's Committee on Measuring Lead Exposure in Critical Populations, concurs with new findings issued by the Centers for Disease Control which state that lead…

Sleep disturbances as predictors of prolonged exposure therapy effectiveness among veterans with PTSD.

PubMed

Sexton, Minden B; Avallone, Kimberly M; Smith, Erin R; Porter, Katherine E; Ashrafioun, Lisham; Todd Arnedt, J; Rauch, Sheila A M

2017-10-01

Sleep disturbances (SD) are pronounced in Veterans with posttraumatic stress disorder (PTSD). In clinical trials, SD have been shown to limit the effectiveness of evidence-based treatments for non-PTSD disorders. The purpose of this study was to investigate the relationships between pretreatment SD and the effectiveness of Prolonged Exposure (PE) therapy for Veterans with PTSD. Twenty-one Veterans completed the Pittsburgh Sleep Quality Index (PSQI) and the Clinician Administered PTSD Scale upon presenting to a PTSD specialty clinic. Veterans completed the PTSD Symptom Checklist-Civilian (PCL-C) at the initiation of PE and biweekly thereafter for the duration of treatment (96 total assessments). Correlations and hierarchical linear modeling were utilized to examine the potential impact of baseline sleep variables on the slope and magnitude of treatment outcomes. Higher PSQI total scores, and higher sleep latency and sleep medication use subscale scores were associated with higher PCL-C scores at baseline. Veterans evidenced significant reductions in PTSD symptoms during the course of the treatment study. Total PSQI scores and composites were not associated with reduced effectiveness of PE treatment or the slope of PTSD symptom changes. Sleep disturbances do not preclude Veterans from benefits derived from engagement in this gold standard PTSD intervention. Published by Elsevier B.V.

Occupational exposures and chronic respiratory symptoms: a population-based study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Korn, R.J.; Dockery, D.W.; Speizer, F.E.

1987-01-01

Data from a random sample of 8515 white adults residing in six cities in the eastern and midwestern United States were used to examine the relationships between occupational exposures to dust or to gases and fumes and chronic respiratory symptoms. 31% of the population had a history of occupational dust exposure and 30% reported exposure to gas or to fumes. After adjusting for smoking habits, age, gender, and city of residence, subjects with either occupational exposure had significantly elevated prevalence of chronic cough, chronic phlegm, persistent wheeze, and breathlessness. The adjusted relative odds of chronic respiratory symptoms for subjects exposedmore » to dust ranged from 1.32 to 1.60. Subjects with gas or fume exposure had relative odds of symptoms between 1.27 and 1.43 when compared to unexposed subjects. Occupational dust exposure was associated with a higher prevalence of chronic obstructive pulmonary disease (COPD) as defined by an FEV1/FVC ratio of less than 0.6, when comparing exposed and unexposed participants (OR=1.53, 95% CI=1.17-2.08). Gas or fume exposure was associated with a small, but not significant, increase in COPD prevalence. Significant trends were noted for wheeze and phlegm with increasing duration of dust exposure. Although 36% of exposed subjects reported exposure to both dust and fumes, there was no evidence of a multiplicative interaction between the effects of the individual exposures. Smoking was a significant independent predictor of symptoms, but did not appear to modify the effect of dust or fumes on symptom reporting. These data, obtained in random samples of general populations, demonstrate that chronic respiratory disease can be independently associated with occupational exposures.« less

Occupational exposures and chronic respiratory symptoms. A population-based study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Korn, R.J.; Dockery, D.W.; Speizer, F.E.

1987-08-01

Data from a random sample of 8515 white adults residing in 6 cities in the eastern and midwestern United States were used to examine the relationships between occupational exposures to dust or to gases and fumes and chronic respiratory symptoms; 31% of the population had a history of occupational dust exposure and 30% reported exposure to gas or fumes. After adjusting for smoking habits, age, gender, and city of residence, subjects with either occupational exposure had significantly elevated prevalences of chronic cough, chronic phlegm, persistent wheeze, and breathlessness. The adjusted relative odds of chronic respiratory symptoms for subjects exposed tomore » dust ranged from 1.32 to 1.60. Subjects with gas or fume exposure had relative odds of symptoms between 1.27 and 1.43 when compared with unexposed subjects. Occupational dust exposure was associated with a higher prevalence of chronic obstructive pulmonary disease as defined by an FEV1/FVC ratio of less than 0.6, when comparing exposed and unexposed participants (OR = 1.53, 95% Cl = 1.17-2.08). Gas or fume exposure was associated with a small, but not significant, increase in COPD prevalence. Significant trends were noted for wheeze and phlegm with increasing duration of dust exposure. Although 36% of exposed subjects reported exposure to both dust and fumes, there was no evidence of a multiplicative interaction between the effects of the individual exposures. Smoking was a significant independent predictor of symptoms, but did not appear to modify the effect of dust or fumes on symptom reporting. These data, obtained in random samples of general populations, demonstrate that chronic respiratory symptoms and disease can be independently associated with occupational exposures.« less

Sea lice and salmon population dynamics: effects of exposure time for migratory fish.

PubMed

Krkosek, Martin; Morton, Alexandra; Volpe, John P; Lewis, Mark A

2009-08-07

The ecological impact of parasite transmission from fish farms is probably mediated by the migration of wild fishes, which determines the period of exposure to parasites. For Pacific salmon and the parasitic sea louse, Lepeophtheirus salmonis, analysis of the exposure period may resolve conflicting observations of epizootic mortality in field studies and parasite rejection in experiments. This is because exposure periods can differ by 2-3 orders of magnitude, ranging from months in the field to hours in experiments. We developed a mathematical model of salmon-louse population dynamics, parametrized by a study that monitored naturally infected juvenile salmon held in ocean enclosures. Analysis of replicated trials indicates that lice suffer high mortality, particularly during pre-adult stages. The model suggests louse populations rapidly decline following brief exposure of juvenile salmon, similar to laboratory study designs and data. However, when the exposure period lasts for several weeks, as occurs when juvenile salmon migrate past salmon farms, the model predicts that lice accumulate to abundances that can elevate salmon mortality and depress salmon populations. The duration of parasite exposure is probably critical to salmon-louse population dynamics, and should therefore be accommodated in coastal planning and management where fish farms are situated on wild fish migration routes.

Prolonged inorganic arsenite exposure suppresses insulin-stimulated AKT S473 phosphorylation and glucose uptake in 3T3-L1 adipocytes: involvement of the adaptive antioxidant response.

PubMed

Xue, Peng; Hou, Yongyong; Zhang, Qiang; Woods, Courtney G; Yarborough, Kathy; Liu, Huiyu; Sun, Guifan; Andersen, Melvin E; Pi, Jingbo

2011-04-08

There is growing evidence that chronic exposure of humans to inorganic arsenic, a potent environmental oxidative stressor, is associated with the incidence of type 2 diabetes (T2D). One critical feature of T2D is insulin resistance in peripheral tissues, especially in mature adipocytes, the hallmark of which is decreased insulin-stimulated glucose uptake (ISGU). Despite the deleterious effects of reactive oxygen species (ROS), they have been recognized as a second messenger serving an intracellular signaling role for insulin action. Nuclear factor erythroid 2-related factor 2 (NRF2) is a central transcription factor regulating cellular adaptive response to oxidative stress. This study proposes that in response to arsenic exposure, the NRF2-mediated adaptive induction of endogenous antioxidant enzymes blunts insulin-stimulated ROS signaling and thus impairs ISGU. Exposure of differentiated 3T3-L1 cells to low-level (up to 2 μM) inorganic arsenite (iAs³(+)) led to decreased ISGU in a dose- and time-dependent manner. Concomitant to the impairment of ISGU, iAs³(+) exposure significantly attenuated insulin-stimulated intracellular ROS accumulation and AKT S473 phosphorylation, which could be attributed to the activation of NRF2 and induction of a battery of endogenous antioxidant enzymes. In addition, prolonged iAs³(+) exposure of 3T3-L1 adipocytes resulted in significant induction of inflammatory response genes and decreased expression of adipogenic genes and glucose transporter type 4 (GLUT4), suggesting chronic inflammation and reduction in GLUT4 expression may also be involved in arsenic-induced insulin resistance in adipocytes. Taken together our studies suggest that prolonged low-level iAs³(+) exposure activates the cellular adaptive oxidative stress response, which impairs insulin-stimulated ROS signaling that is involved in ISGU, and thus causes insulin resistance in adipocytes. Copyright © 2011 Elsevier Inc. All rights reserved.

Prolonged inorganic arsenite exposure suppresses insulin-stimulated AKT S473 phosphorylation and glucose uptake in 3T3-L1 adipocytes: Involvement of the adaptive antioxidant response

PubMed Central

Xue, Peng; Hou, Yongyong; Zhang, Qiang; Woods, Courtney G.; Yarborough, Kathy; Liu, Huiyu; Sun, Guifan; Andersen, Melvin E.; Pi, Jingbo

2011-01-01

There is growing evidence that chronic exposure of humans to inorganic arsenic, a potent environmental oxidative stressor, is associated with the incidence of type 2 diabetes (T2D). One critical feature of T2D is insulin resistance in peripheral tissues, especially in mature adipocytes, the hallmark of which is decreased insulin-stimulated glucose uptake (ISGU). Despite the deleterious effects of reactive oxygen species (ROS), they have been recognized as a second messenger serving an intracellular signaling role for insulin action. Nuclear factor erythroid 2-related factor 2 (NRF2) is a central transcription factor regulating cellular adaptive response to oxidative stress. This study proposes that in response to arsenic exposure, the NRF2-mediated adaptive induction of endogenous antioxidant enzymes blunts insulin-stimulated ROS signaling and thus impairs ISGU. Exposure of differentiated 3T3-L1 cells to low-level (up to 2 μM) inorganic arsenite (iAs3+) led to decreased ISGU in a dose- and time-dependent manner. Concomitant to the impairment of ISGU, iAs3+ exposure significantly attenuated insulin-stimulated intracellular ROS accumulation and AKT S473 phosphorylation, which could be attributed to the activation of NRF2 and induction of a battery of endogenous antioxidant enzymes. In addition, prolonged iAs3+ exposure of 3T3-L1 adipocytes resulted in significant induction of inflammatory response genes and decreased expression of adipogenic genes and glucose transporter type 4 (GLUT4), suggesting chronic inflammation and reduction in GLUT4 expression may also be involved in arsenic-induced insulin resistance in adipocytes. Taken together our studies suggest that prolonged low-level iAs3+ exposure activates the cellular adaptive oxidative stress response, which impairs insulin-stimulated ROS signaling that is involved in ISGU, and thus causes insulin resistance in adipocytes. PMID:21396911

Human physiological responses to cold exposure: Acute responses and acclimatization to prolonged exposure.

PubMed

Castellani, John W; Young, Andrew J

2016-04-01

Cold exposure in humans causes specific acute and chronic physiological responses. This paper will review both the acute and long-term physiological responses and external factors that impact these physiological responses. Acute physiological responses to cold exposure include cutaneous vasoconstriction and shivering thermogenesis which, respectively, decrease heat loss and increase metabolic heat production. Vasoconstriction is elicited through reflex and local cooling. In combination, vasoconstriction and shivering operate to maintain thermal balance when the body is losing heat. Factors (anthropometry, sex, race, fitness, thermoregulatory fatigue) that influence the acute physiological responses to cold exposure are also reviewed. The physiological responses to chronic cold exposure, also known as cold acclimation/acclimatization, are also presented. Three primary patterns of cold acclimatization have been observed, a) habituation, b) metabolic adjustment, and c) insulative adjustment. Habituation is characterized by physiological adjustments in which the response is attenuated compared to an unacclimatized state. Metabolic acclimatization is characterized by an increased thermogenesis, whereas insulative acclimatization is characterized by enhancing the mechanisms that conserve body heat. The pattern of acclimatization is dependent on changes in skin and core temperature and the exposure duration. Published by Elsevier B.V.

Land Use as a Driver of Patterns of Rodenticide Exposure in Modeled Kit Fox Populations

PubMed Central

Nogeire, Theresa M.; Lawler, Joshua J.; Schumaker, Nathan H.; Cypher, Brian L.; Phillips, Scott E.

2015-01-01

Although rodenticides are increasingly regulated, they nonetheless cause poisonings in many non-target wildlife species. Second-generation anticoagulant rodenticide use is common in agricultural and residential landscapes. Here, we use an individual-based population model to assess potential population-wide effects of rodenticide exposures on the endangered San Joaquin kit fox (Vulpes macrotis mutica). We estimate likelihood of rodenticide exposure across the species range for each land cover type based on a database of reported pesticide use and literature. Using a spatially-explicit population model, we find that 36% of modeled kit foxes are likely exposed, resulting in a 7-18% decline in the range-wide modeled kit fox population that can be linked to rodenticide use. Exposures of kit foxes in low-density developed areas accounted for 70% of the population-wide exposures to rodenticides. We conclude that exposures of non-target kit foxes could be greatly mitigated by reducing the use of second-generation anticoagulant rodenticides in low-density developed areas near vulnerable populations. PMID:26244655

Differential tolerance to cyanobacterial exposure between geographically distinct populations of Perca fluviatilis.

PubMed

Persson, Karl-Johan; Bergström, Kristofer; Mazur-Marzec, Hannah; Legrand, Catherine

2013-12-15

Toxic cyanobacterial blooms are an important problem worldwide. Cyanobacteria may negatively impact young-of-the-year (YOY) fish directly (toxin production, turbidity, decrease in water quality) or indirectly (trophic toxin transfer, changes in prey species composition). Here we test whether there are any differences in cyanobacterial tolerance between four geographically distinct populations of European perch (Perca fluviatilis). We show that P. fluviatilis may develop tolerance against cyanobacteria demonstrated by the ability of individuals from a marine site (exposed to annual cyanobacterial blooms) to increase their detoxification more than individuals from an oligotrophic site (rarely exposed to cyanobacteria). Our results also revealed significant interaction effects between genotypes within a population and response to cyanobacterial exposure in terms of absolute growth and detoxification activity. This genotype by treatment interaction may result in local adaptations to cyanobacterial exposure in P. fluviatilis. Hence, the sensitivity against cyanobacterial exposure may differ between within species populations increasing the importance of local management of fish populations. Copyright © 2013 Elsevier Ltd. All rights reserved.

RESPIRATORY DOSE TO SUSCEPTIBLE POPULATIONS ASSESSED BY EXPOSURE AND DOSIMETRY STUDIES

EPA Science Inventory

Respiratory Dose to Susceptible Populations Assessed by Exposure and Dosimetry Studies

Chong Kim1 and Ronald Williams2, 1USEPA National Health and Environmental Effects Research Laboratory and 2USEPA National Exposure Research Laboratory, RTP, NC.

Rationale: Parti...

SHEDS-PM: A POPULATION EXPOSURE MODEL FOR PREDICTING DISTRIBUTIONS OF PM EXPOSURE AND DOSE FROM BOTH OUTDOOR AND INDOOR SOURCES

EPA Science Inventory

The US EPA National Exposure Research Laboratory (NERL) has developed a population exposure and dose model for particulate matter (PM), called the Stochastic Human Exposure and Dose Simulation (SHEDS) model. SHEDS-PM uses a probabilistic approach that incorporates both variabi...

Chronotype and environmental light exposure in a student population.

PubMed

Porcheret, Kate; Wald, Lucien; Fritschi, Lin; Gerkema, Menno; Gordijn, Marijke; Merrrow, Martha; Rajaratnam, Shantha M W; Rock, Daniel; Sletten, Tracey L; Warman, Guy; Wulff, Katharina; Roenneberg, Till; Foster, Russell G

2018-06-18

In humans and most other species, changes in the intensity and duration of light provide a critical set of signals for the synchronisation of the circadian system to the astronomical day. The timing of activity within the 24 h day defines an individual's chronotype, i.e. morning, intermediate or evening type. The aim of this study was to investigate the associations between environmental light exposure, due to geographical location, on the chronotype of university students. Over 6 000 university students from cities in the Northern Hemisphere (Oxford, Munich and Groningen) and Southern Hemisphere (Perth, Melbourne and Auckland) completed the Munich ChronoType Questionnaire. In parallel, light measures (daily irradiance, timing of sunrise and sunset) were compiled from satellite or ground stations at each of these locations. Our data shows that later mid-sleep point on free days (corrected for oversleep on weekends MFS sc ) is associated with (i) residing further from the equator, (ii) a later sunset, (iii) spending more time outside and (iv) waking from sleep significantly after sunrise. However, surprisingly, MSF sc did not correlate with daily light intensity at the different geographical locations. Although these findings appear to contradict earlier studies suggesting that in the wider population increased light exposure is associated with an earlier chronotype, our findings are derived exclusively from a student population aged between 17 and 26 years. We therefore suggest that the age and occupation of our population increase the likelihood that these individuals will experience relatively little light exposure in the morning whilst encountering more light exposure later in the day, when light has a delaying effect upon the circadian system.

Exposure to genocide and the risk of schizophrenia: a population-based study.

PubMed

Levine, S Z; Levav, I; Goldberg, Y; Pugachova, I; Becher, Y; Yoffe, R

2016-03-01

No evidence exists on the association between genocide and the incidence of schizophrenia. This study aims to identify critical periods of exposure to genocide on the risk of schizophrenia. This population-based study comprised of all subjects born in European nations where the Holocaust occurred from 1928 to 1945, who immigrated to Israel by 1965 and were indexed in the Population Register (N = 113 932). Subjects were followed for schizophrenia disorder in the National Psychiatric Case Registry from 1950 to 2014. The population was disaggregated to compare groups that immigrated before (indirect exposure: n = 8886, 7.8%) or after (direct exposure: n = 105 046, 92.2%) the Nazi or fascist era of persecutions began. The latter group was further disaggregated to examine likely initial prenatal or postnatal genocide exposures. Cox regression modelling was computed to compare the risk of schizophrenia between the groups, adjusting for confounders. The likely direct group was at a statistically (p < 0.05) greater risk of schizophrenia (hazard ratio = 1.27, 95% confidence interval 1.06-1.51) than the indirect group. Also, the likely combined in utero and postnatal, and late postnatal (over age 2 years) exposure subgroups were statistically at greater risk of schizophrenia than the indirect group (p < 0.05). The likely in utero only and early postnatal (up to age 2 years) exposure subgroups compared with the indirect exposure group did not significantly differ. These results were replicated across three sensitivity analyses. This study showed that genocide exposure elevated the risk of schizophrenia, and identified in utero and postnatal (combined) and late postnatal (age over 2 years) exposures as critical periods of risk.

Estimating the long-term historic evolution of exposure to flooding of coastal populations

NASA Astrophysics Data System (ADS)

Stevens, A. J.; Clarke, D.; Nicholls, R. J.; Wadey, M. P.

2015-06-01

Coastal managers face the task of assessing and managing flood risk. This requires knowledge of the area of land, the number of people, properties and other infrastructure potentially affected by floods. Such analyses are usually static; i.e. they only consider a snapshot of the current situation. This misses the opportunity to learn about the role of key drivers of historical changes in flood risk, such as development and population rise in the coastal flood plain, as well as sea-level rise. In this paper, we develop and apply a method to analyse the temporal evolution of residential population exposure to coastal flooding. It uses readily available data in a GIS environment. We examine how population and sea-level change have modified exposure over two centuries in two neighbouring coastal sites: Portsea and Hayling Islands on the UK south coast. The analysis shows that flood exposure changes as a result of increases in population, changes in coastal population density and sea level rise. The results indicate that to date, population change is the dominant driver of the increase in exposure to flooding in the study sites, but climate change may outweigh this in the future. A full analysis of changing flood risk is not possible as data on historic defences and wider vulnerability are not available. Hence, the historic evolution of flood exposure is as close as we can get to a historic evolution of flood risk. The method is applicable anywhere that suitable floodplain geometry, sea level and population data sets are available and could be widely applied, and will help inform coastal managers of the time evolution in coastal flood drivers.

Prolonged Pulmonary Exposure to Diesel Exhaust Particles Exacerbates Renal Oxidative Stress, Inflammation and DNA Damage in Mice with Adenine-Induced Chronic Renal Failure.

PubMed

Nemmar, Abderrahim; Karaca, Turan; Beegam, Sumaya; Yuvaraju, Priya; Yasin, Javed; Hamadi, Naserddine Kamel; Ali, Badreldin H

2016-01-01

Epidemiological evidence indicates that patients with chronic kidney diseases have increased susceptibility to adverse outcomes related to long-term exposure to particulate air pollution. However, mechanisms underlying these effects are not fully understood. Presently, we assessed the effect of prolonged exposure to diesel exhaust particles (DEP) on chronic renal failure induced by adenine (0.25% w/w in feed for 4 weeks), which is known to involve inflammation and oxidative stress. DEP (0.5m/kg) was intratracheally (i.t.) instilled every 4th day for 4 weeks (7 i.t. instillation). Four days following the last exposure to either DEP or saline (control), various renal endpoints were measured. While body weight was decreased, kidney weight increased in DEP+adenine versus saline+adenine or DEP. Water intake, urine volume, relative kidney weight were significantly increased in adenine+DEP versus DEP and adenine+saline versus saline. Plasma creatinine and urea increased and creatinine clearance decreased in adenine+DEP versus DEP and adenine+saline versus saline. Tumor necrosis factor α, lipid peroxidation and reactive oxygen species were significantly increased in adenine+DEP compared with either DEP or adenine+saline. The antioxidant calase was significantly decreased in adenine+DEP compared with either adenine+saline or DEP. Notably, renal DNA damage was significantly potentiated in adenine+DEP compared with either adenine+saline or DEP. Similarly, systolic blood pressure was increased in adenine+DEP versus adenine+saline or DEP, and in DEP versus saline. Histological evaluation revealed more collagen deposition, higher number of necrotic cell counts and dilated tubules, cast formation and collapsing glomeruli in adenine+DEP versus adenine+saline or DEP. Prolonged pulmonary exposure to diesel exhaust particles worsen renal oxidative stress, inflammation and DNA damage in mice with adenine-induced chronic renal failure. Our data provide biological plausibility that air

Does Use of Low-Molecular-Weight Heparin during Pregnancy Influence the Risk of Prolonged Labor: A Population-Based Cohort Study

PubMed Central

Sandström, Anna; Cnattingius, Sven; Wikström, Anna-Karin

2015-01-01

Background The use of low-molecular-weight heparins (LMWHs) during pregnancy is increasing. In vitro studies and small clinical studies support the hypothesis that LMWH treatment during pregnancy may reduce duration of labor. The aim of this study was to investigate if use of LMWH is associated with a reduced risk of diagnosis of prolonged labor, after taking maternal, fetal and other delivery characteristics into account. Methods and Findings A population-based cohort study from the Swedish Medical Birth Register from April 2006 through December 2011. We identified 514 875 term (≥37 weeks) deliveries of live singleton infants in cephalic presentation with spontaneous or induced onsets of labor. The Birth Register was linked to the Prescribed Drug Register to retrieve information on dispensed LMWH during pregnancy and to the Patient Register for information on underlying diagnosis for use of LMWH. Diagnosis of prolonged labor in the Birth Register was retrieved from diagnosis at discharge from the delivery hospital. The risk of diagnosis of prolonged labor in relation to treatment with LMWH was assessed using logistic regression analysis to estimate unadjusted and adjusted odds ratios. A total of 5 275 (1.0%) of the pregnant women used LMWH. The absolute risk of diagnosis of prolonged labor for nulliparous women was 19.9% among women using LMWH in third trimester, and 21.2% in women without use of LMWH. For parous women the corresponding absolute risks were 4.3% and 4.7%, respectively. Compared to nulliparous women without use of LMWH, nulliparous women with LMWH during third trimester had an odds ratio (OR) of 0.92 (95% CI 0.81–1.05, p-value: 0.051) for diagnosis of prolonged labor in unadjusted analyses and after adjustments for maternal characteristics, gestational age and epidural analgesia the OR was 1.00 (95% CI 0.87–1.15, p-value: 0.673). Parous women treated with LMWH in third trimester presented the same pattern, unadjusted OR for diagnosis of

Prolonged pupal dormancy is associated with significant fitness cost for adults of Rhagoletis cerasi (Diptera: Tephritidae).

PubMed

Moraiti, Cleopatra A; Nakas, Christos T; Papadopoulos, Nikos T

2012-08-01

In temperate areas, dormancy (diapause and/or quiescence) enables herbivorous insect species to persist and thrive by synchronizing growth and reproduction with the seasonal phenology of their host plants. Within-population variability in dormancy increases survival chances under unpredictable environmental changes. However, prolonged dormancy may be costly, incurring trade-offs in important adult fitness traits such as life span and reproduction. We used the European cherry fruit fly, Rhagoletis cerasi, a stenophagous, univoltine species that overwinters in the pupal stage for usually one or more years to test the hypotheses that prolonged dormancy of pupae has trade-offs with body size, survival and reproduction of the resulting adults. We used two geographically isolated populations of R. cerasi to compare the demographic traits of adults obtained from pupae subjected to one or two cycles of warm-cold periods (annual and prolonged dormancy respectively). Regardless of population, adults from pupae that experienced prolonged dormancy were larger than counterparts emerging within 1year. Prolonged dormancy did not affect adult longevity but both lifetime fecundity and oviposition were significantly decreased. Extension of the life cycle of some individuals in R. cerasi populations in association with prolonged dormancy is likely a bet-hedging strategy. Copyright © 2012 Elsevier Ltd. All rights reserved.

Prenatal Nicotinic Exposure Upregulates Pulmonary C-fiber NK1R Expression to Prolong Pulmonary C-fiber-Mediated Apneic Response

PubMed Central

Zhao, Lei; Zhuang, Jianguo; Zang, Na; Lin, Yong; Lee, Lu-Yuan; Xu, Fadi

2015-01-01

Prenatal nicotinic exposure (PNE) prolongs bronchopulmonary C-fiber (PCF)-mediated apneic response to intra-atrial bolus injection of capsaicin in rat pups. The relevant mechanisms remain unclear. Pulmonary substance P and adenosine and their receptors (neurokinin-A receptor, NK1R and ADA1 receptor, ADA1R) and transient receptor potential cation channel subfamily V member 1 (TRPV1) expressed on PCFs are critical for PCF sensitization and/or activation. Here, we compared substance P and adenosine in BALF and NK1R, ADA1R, and TRPV1 expression in the nodose/jugular (N/J) ganglia (vagal pulmonary C-neurons retrogradely labeled) between Ctrl and PNE pups. We found that PNE failed to change BALF substance P and adenosine content, but significantly upregulated both mRNA and protein TRPV1 and NK1R in the N/J ganglia and only NK1R mRNA in pulmonary C-neurons. To define the role of NK1R in the PNE-induced PCF sensitization, the apneic response to capsaicin (i.v.) without or with pretreatment of SR140333 (a peripheral and selective NK1R antagonist) was compared and the prolonged apnea by PNE significantly shortened by SR140333. To clarify if the PNE-evoked responses depended on action of nicotinic acetylcholine receptors (nAChRs), particularly α7nAChR, mecamylamine or methyllycaconitine (a general nAChRs or a selective α7nAChR antagonist) was administrated via another mini-pump over the PNE period. Mecamylamine or methyllycaconitine eliminated the PNE-evoked mRNA and protein responses. Our data suggest that PNE is able to elevate PCF NK1R expression via activation of nAChRs, especially α7nAChR, which likely contributes to sensitize PCFs and prolong the PCF-mediated apneic response to capsaicin. PMID:26524655

Sun exposure profile in the French population. Results of the EDIFICE Melanoma survey.

PubMed

Sassolas, B; Grange, F; Touboul, C; Lebbe, C; Saiag, P; Mortier, L; Lhomel, C; Robert, C

2015-02-01

The incidence of melanoma is increasing worldwide, causing significant economic burden at community and individual levels. Ultraviolet radiation, from natural sunlight or artificial sources, is the main environmental, modifiable risk factor for melanoma. The present analysis assesses the profile of sun exposure in the French population as well as the level of awareness about ultraviolet risk and protection. The survey was conducted via telephone interviews in September and October 2011. In total, 1502 respondents were questioned about their own sun exposure with the question "do you ever, even occasionally, spend time in the sun, during leisure-time, vacation or your professional occupation?" They were also asked about sun protection measures used: protective clothing, a hat or sunscreen. More than three respondents out of four (78%) declared exposing themselves to the sun, with an average of 113 days per year. Of these, 38% did not use appropriate sun protection measures. We identified the following characteristics of individuals declaring high sun exposure: chiefly men under the age of 40, higher socio-professional levels, and adults with no children. Individuals who make a poor use of protective measures are mostly men and of low educational levels. Individuals declaring low sun exposure were chiefly: women, individuals over the age of 60, and those with no professional activity. The high sun protection population comprises mostly: women, higher socio-professional levels, with no specific age-group profile. Analysis of the EDIFICE Melanoma survey provides information about the attitudes of the French population towards sun exposure. The most frequent contexts of sun exposure and the associated socio-demographic characteristics of the population with at-risk attitudes regarding sun exposure are identified. This deeper insight into the profile of at-risk populations will allow interventions to be more accurately targeted, thus potentially improving public health

Reconstructing population exposures to environmental chemicals from biomarkers: challenges and opportunities.

PubMed

Georgopoulos, Panos G; Sasso, Alan F; Isukapalli, Sastry S; Lioy, Paul J; Vallero, Daniel A; Okino, Miles; Reiter, Larry

2009-02-01

A conceptual/computational framework for exposure reconstruction from biomarker data combined with auxiliary exposure-related data is presented, evaluated with example applications, and examined in the context of future needs and opportunities. This framework employs physiologically based toxicokinetic (PBTK) modeling in conjunction with numerical "inversion" techniques. To quantify the value of different types of exposure data "accompanying" biomarker data, a study was conducted focusing on reconstructing exposures to chlorpyrifos, from measurements of its metabolite levels in urine. The study employed biomarker data as well as supporting exposure-related information from the National Human Exposure Assessment Survey (NHEXAS), Maryland, while the MENTOR-3P system (Modeling ENvironment for TOtal Risk with Physiologically based Pharmacokinetic modeling for Populations) was used for PBTK modeling. Recently proposed, simple numerical reconstruction methods were applied in this study, in conjunction with PBTK models. Two types of reconstructions were studied using (a) just the available biomarker and supporting exposure data and (b) synthetic data developed via augmenting available observations. Reconstruction using only available data resulted in a wide range of variation in estimated exposures. Reconstruction using synthetic data facilitated evaluation of numerical inversion methods and characterization of the value of additional information, such as study-specific data that can be collected in conjunction with the biomarker data. Although the NHEXAS data set provides a significant amount of supporting exposure-related information, especially when compared to national studies such as the National Health and Nutrition Examination Survey (NHANES), this information is still not adequate for detailed reconstruction of exposures under several conditions, as demonstrated here. The analysis presented here provides a starting point for introducing improved designs for future

Prolonged exposure to bacterial toxins downregulated expression of toll-like receptors in mesenchymal stromal cell-derived osteoprogenitors

PubMed Central

Mo, Irene Fung Ying; Yip, Kevin Hak Kong; Chan, Wing Keung; Law, Helen Ka Wai; Lau, Yu Lung; Chan, Godfrey Chi Fung

2008-01-01

Background Human mesenchymal stromal cells (MSCs, also known as mesenchymal stem cells) are multipotent cells with potential therapeutic value. Owing to their osteogenic capability, MSCs may be clinically applied for facilitating osseointegration in dental implants or orthopedic repair of bony defect. However, whether wound infection or oral microflora may interfere with the growth and osteogenic differentiation of human MSCs remains unknown. This study investigated whether proliferation and osteogenic differentiation of MSCs would be affected by potent gram-positive and gram-negative derived bacterial toxins commonly found in human settings. Results We selected lipopolysaccharide (LPS) from Escherichia coli and lipoteichoic acid (LTA) from Streptococcus pyogenes as our toxins of choice. Our findings showed both LPS and LTA did not affect MSC proliferation, but prolonged LPS challenge upregulated the osteogenic differentiation of MSCs, as assessed by alkaline phosphatase activity and calcium deposition. Because toll-like receptors (TLRs), in particularly TLR4 and TLR2, are important for the cellular responsiveness to LPS and LTA respectively, we evaluated their expression profiles serially from MSCs to osteoblasts by quantitative PCR. We found that during osteogenic differentiation, MSC-derived osteoprogenitors gradually expressed TLR2 and TLR4 by Day 12. But under prolonged incubation with LPS, MSC-derived osteoprogenitors had reduced TLR2 and TLR4 gene expression. This peculiar response to LPS suggests a possible adaptive mechanism when MSCs are subjected to continuous exposure with bacteria. Conclusion In conclusion, our findings support the potential of using human MSCs as a biological graft, even under a bacterial toxin-rich environment. PMID:18799018

Effects on respiratory homeostasis of prolonged, continuous hyperoxia at 1.5 to 3.0 ATA in man in Predictive Studies V

NASA Technical Reports Server (NTRS)

Gelfand, R.; Clark, J. M.; Lambertsen, C. J.; Pisarello, J. B.

1987-01-01

Prolonged exposures of men to continuous hyperoxia at 3.0, 2.5, 2.0, and 1.5 ATA were conducted to define CNS oxygen tolerance and to investigate the effects of prolonged hyperoxia on CNS and other organ functions. Altered respiratory homeostasis was evident during exposures of men to 2.5 and 3.0 ATA O2 as nonprogressive increment in ventilation and reciprocal decrement in PET(CO2). These changes were progressive during exposure at 1.5 ATA O2. Mean values of respiratory reactivity at CO2 were somewhat increased following prolonged hyperoxia at 1.5 and 2.5 ATA, compared to preexposure mean values. Hypoxic ventilatory response was unchanged or enhanced after oxygen exposures at 1.5 and 2.5 ATA. Observed respiratory and body temperature changes were not of sufficient magnitude to impair function.

Satellite-aided evaluation of population exposure to air pollution

NASA Technical Reports Server (NTRS)

Todd, W. J.; George, A. J., Jr.; Bryant, N. A.

1979-01-01

The evaluation of population exposure to air pollution through the computer processing of Landsat digital land use data, along with total suspended particulate estimates and population data by census tracts, is demonstrated. Digital image processing was employed to analyze simultaneously data from Landsat MSS bands 4 through 7 in order to extract land use and land cover information. The three data sets were spatially registered in a digital format, compatible with integrated computer processing, and cross-tabulated. A map illustrating relative air quality by 2-sq km cells for the residential population in the Portland, Oregon area is obtained.

Characterizing prolonged heat effects on mortality in a sub-tropical high-density city, Hong Kong

NASA Astrophysics Data System (ADS)

Ho, Hung Chak; Lau, Kevin Ka-Lun; Ren, Chao; Ng, Edward

2017-11-01

Extreme hot weather events are likely to increase under future climate change, and it is exacerbated in urban areas due to the complex urban settings. It causes excess mortality due to prolonged exposure to such extreme heat. However, there is lack of universal definition of prolonged heat or heat wave, which leads to inadequacies of associated risk preparedness. Previous studies focused on estimating temperature-mortality relationship based on temperature thresholds for assessing heat-related health risks but only several studies investigated the association between types of prolonged heat and excess mortality. However, most studies focused on one or a few isolated heat waves, which cannot demonstrate typical scenarios that population has experienced. In addition, there are limited studies on the difference between daytime and nighttime temperature, resulting in insufficiency to conclude the effect of prolonged heat. In sub-tropical high-density cities where prolonged heat is common in summer, it is important to obtain a comprehensive understanding of prolonged heat for a complete assessment of heat-related health risks. In this study, six types of prolonged heat were examined by using a time-stratified analysis. We found that more consecutive hot nights contribute to higher mortality risk while the number of consecutive hot days does not have significant association with excess mortality. For a day after five consecutive hot nights, there were 7.99% [7.64%, 8.35%], 7.74% [6.93%, 8.55%], and 8.14% [7.38%, 8.88%] increases in all-cause, cardiovascular, and respiratory mortality, respectively. Non-consecutive hot days or nights are also found to contribute to short-term mortality risk. For a 7-day-period with at least five non-consecutive hot days and nights, there was 15.61% [14.52%, 16.70%] increase in all-cause mortality at lag 0-1, but only -2.00% [-2.83%, -1.17%] at lag 2-3. Differences in the temperature-mortality relationship caused by hot days and hot nights

Characterizing prolonged heat effects on mortality in a sub-tropical high-density city, Hong Kong.

PubMed

Ho, Hung Chak; Lau, Kevin Ka-Lun; Ren, Chao; Ng, Edward

2017-11-01

Extreme hot weather events are likely to increase under future climate change, and it is exacerbated in urban areas due to the complex urban settings. It causes excess mortality due to prolonged exposure to such extreme heat. However, there is lack of universal definition of prolonged heat or heat wave, which leads to inadequacies of associated risk preparedness. Previous studies focused on estimating temperature-mortality relationship based on temperature thresholds for assessing heat-related health risks but only several studies investigated the association between types of prolonged heat and excess mortality. However, most studies focused on one or a few isolated heat waves, which cannot demonstrate typical scenarios that population has experienced. In addition, there are limited studies on the difference between daytime and nighttime temperature, resulting in insufficiency to conclude the effect of prolonged heat. In sub-tropical high-density cities where prolonged heat is common in summer, it is important to obtain a comprehensive understanding of prolonged heat for a complete assessment of heat-related health risks. In this study, six types of prolonged heat were examined by using a time-stratified analysis. We found that more consecutive hot nights contribute to higher mortality risk while the number of consecutive hot days does not have significant association with excess mortality. For a day after five consecutive hot nights, there were 7.99% [7.64%, 8.35%], 7.74% [6.93%, 8.55%], and 8.14% [7.38%, 8.88%] increases in all-cause, cardiovascular, and respiratory mortality, respectively. Non-consecutive hot days or nights are also found to contribute to short-term mortality risk. For a 7-day-period with at least five non-consecutive hot days and nights, there was 15.61% [14.52%, 16.70%] increase in all-cause mortality at lag 0-1, but only -2.00% [-2.83%, -1.17%] at lag 2-3. Differences in the temperature-mortality relationship caused by hot days and hot nights

Subtleties in practical application of prolonged infusion of β-lactam antibiotics.

PubMed

De Waele, Jan J; Lipman, Jeffrey; Carlier, Mieke; Roberts, Jason A

2015-05-01

Prolonged infusion (PI) of β-lactam antibiotics is increasingly used in order to optimise antibiotic exposure in critically ill patients. Physicians are often not aware of a number of subtleties that may jeopardise the treatment. In this clinically based paper, we stress pragmatic issues, such as the importance of a loading dose before PI, and discuss a number of important practicalities that are mandatory to benefit from the pharmacokinetic advantages of prolonged β-lactam antibiotic administration. Copyright © 2015 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

A population-based job exposure matrix for power-frequency magnetic fields.

PubMed

Bowman, Joseph D; Touchstone, Jennifer A; Yost, Michael G

2007-09-01

A population-based job exposure matrix (JEM) was developed to assess personal exposures to power-frequency magnetic fields (MF) for epidemiologic studies. The JEM compiled 2,317 MF measurements taken on or near workers by 10 studies in the United States, Sweden, New Zealand, Finland, and Italy. A database was assembled from the original data for six studies plus summary statistics grouped by occupation from four other published studies. The job descriptions were coded into the 1980 Standard Occupational Classification system (SOC) and then translated to the 1980 job categories of the U.S. Bureau of the Census (BOC). For each job category, the JEM database calculated the arithmetic mean, standard deviation, geometric mean, and geometric standard deviation of the workday-average MF magnitude from the combined data. Analysis of variance demonstrated that the combining of MF data from the different sources was justified, and that the homogeneity of MF exposures in the SOC occupations was comparable to JEMs for solvents and particulates. BOC occupation accounted for 30% of the MF variance (p < 10(-6)), and the contrast (ratio of the between-job variance to the total of within- and between-job variances) was 88%. Jobs lacking data had their exposures inferred from measurements on similar occupations. The JEM provided MF exposures for 97% of the person-months in a population-based case-control study and 95% of the jobs on death certificates in a registry study covering 22 states. Therefore, we expect this JEM to be useful in other population-based epidemiologic studies.

Prolonged noise exposure-induced auditory threshold shifts in rats

PubMed Central

Chen, Guang-Di; Decker, Brandon; Muthaiah, Vijaya Prakash Krishnan; Sheppard, Adam; Salvi, Richard

2014-01-01

Noise-induced hearing loss (NIHL) initially increases with exposure duration, but eventually reaches an asymptotic threshold shift (ATS) once the exposure duration exceeds 18-24 h. Equations for predicting the ATS have been developed for several species, but not for rats, even though this species is extensively used in noise exposure research. To fill this void, we exposed rats to narrowband noise (NBN, 16-20 kHz) for 5 weeks starting at 80 dB SPL in the first week and then increasing the level by 6 dB per week to a final level of 104 dB SPL. Auditory brainstem responses (ABR) were recorded before, during, and following the exposure to determine the amount of hearing loss. The noise induced threshold shift to continuous long-term exposure, defined as compound threshold shift (CTS), within and above 16-20 kHz increased with noise level at the rate of 1.82 dB threshold shift per dB of noise level (NL) above a critical level (C) of 77.2 dB SPL i.e. CTS = 1.82(NL-77.2). The normalized amplitude of the largest ABR peak measured at 100 dB SPL decreased at the rate of 3.1% per dB of NL above the critical level of 76.9 dB SPL, i.e., %ABR Reduction = 3.1%(NL-76.9). ABR thresholds measured >30 days post-exposure only partially recovered resulting in a permanent threshold shift of 30-40 dB along with severe hair cell loss in the basal, high-frequency region of the cochlea. In the rat, CTS increases with noise level with a slope similar to humans and chinchillas. The critical level (C) in the rat is similar to that of humans, but higher than that of chinchillas. PMID:25219503

Prolonged second stage of labor is associated with low Apgar score.

PubMed

Altman, Maria; Sandström, Anna; Petersson, Gunnar; Frisell, Thomas; Cnattingius, Sven; Stephansson, Olof

2015-11-01

There is no consensus on the effects of a prolonged second stage of labor on neonatal outcomes. In this large Swedish population-based cohort study, our objective was to investigate prolonged second stage and risk of low Apgar score at 5 min. All nulliparous women (n = 32,796) delivering a live born singleton infant in cephalic presentation at ≥37 completed weeks after spontaneous onset of labor between 2008 and 2012 in the counties of Stockholm and Gotland were included. Data were obtained from computerized records. Exposure was time from fully retracted cervix until delivery. Logistic regression analyses were used to estimate crude and adjusted odds ratios (ORs) with 95% confidence intervals (CIs). Adjustments were made for maternal age, height, BMI, smoking, sex, gestational age, sex-specific birth weight for gestational age and head circumference. Epidural analgesia was included in a second model. The primary outcome measure was Apgar score at 5 min <7 and <4. We found that the overall rates of 5 min Apgar score <7 and <4 were 7.0 and 1.3 per 1000 births, respectively. Compared to women with <1 h from retracted cervix to birth, adjusted ORs of Apgar score <7 at 5 min generally increased with length of second stage of labor: 1 to <2 h: OR 1.78 (95% CI 1.19-2.66); 2 to <3 h: OR 1.66 (1.05-2.62); 3 to <4 h: OR 2.08 (1.29-3.35); and ≥4 h: OR 2.71 (1.67-4.40). We conclude that prolonged second stage of labor is associated with an increased risk of low 5 min Apgar score.

A non-inferiority trial of Prolonged Exposure for posttraumatic stress disorder: In person versus home-based telehealth.

PubMed

Acierno, Ron; Knapp, Rebecca; Tuerk, Peter; Gilmore, Amanda K; Lejuez, Carl; Ruggiero, Kenneth; Muzzy, Wendy; Egede, Leonard; Hernandez-Tejada, Melba A; Foa, Edna B

2017-02-01

This is the first randomized controlled trial to evaluate non-inferiority of Prolonged Exposure (PE) delivered via home-based telehealth (HBT) compared to standard in-person (IP) PE. One-hundred thirty two Veterans recruited from a Southeastern Veterans Affairs Medical Center and affiliated University who met criteria for posttraumatic stress disorder (PTSD) were randomized to receive PE via HBT or PE via IP. Results indicated that PE-HBT was non-inferior to PE-IP in terms of reducing PTSD scores at post-treatment, 3 and 6 month follow-up. However, non-inferiority hypotheses for depression were only supported at 6 month follow-up. HBT has great potential to reduce patient burden associated with receiving treatment in terms of travel time, travel cost, lost work, and stigma without sacrificing efficacy. These findings indicate that telehealth treatment delivered directly into patients' homes may dramatically increase the reach of this evidence-based therapy for PTSD without diminishing effectiveness. Published by Elsevier Ltd.

Prolonged sitting in cars: prevalence, socio-demographic variations, and trends.

PubMed

Sugiyama, Takemi; Merom, Dafna; van der Ploeg, Hidde P; Corpuz, Grace; Bauman, Adrian; Owen, Neville

2012-10-01

Prolonged sitting is detrimentally associated with health outcomes. However, the prevalence and characteristics of those who sit in cars for long periods are not well understood. This study examined the population prevalence, socio-demographic variations, and trends for prolonged sitting in cars among adults. Using the Sydney Greater Metropolitan Area Household Travel Survey, the prevalence of prolonged sitting time in cars (≥2 h/day) was calculated for four 3-year periods (1997-99, 2000-02, 2003-05, and 2006-08) for each population subgroup. Trends were calculated as the mean change in prevalence between adjacent survey periods. Cars were used for 66% of the total trips recorded (n=336,505). The prevalence of prolonged sitting time in cars was 16-18% in men, and 10-12% in women. Relatively higher prevalence rates were found among middle-age groups (men: 20-22%, women: 12-15%), full-time workers (men: 21-24%, women: 14-15%), those with higher income (men: 21-25%, women: 14-16%), couples with children (men: 20-21%, women: 12-14%), and those living in outer suburbs (men: 20-23%, women: 12-13%). Trends were stable in men, but increasing in women. Several subgroups (older age; living in regional suburbs) also showed increasing trends. These findings provide evidence to inform integrated approaches to measurement and policy development on prolonged car use among the public health, urban planning, and transport sectors. Copyright © 2012 Elsevier Inc. All rights reserved.

BOOK REVIEW: NCRP Report No. 160: Ionizing Radiation Exposure of the Population of the United States NCRP Report No. 160: Ionizing Radiation Exposure of the Population of the United States

NASA Astrophysics Data System (ADS)

Thurston, Jim

2010-10-01

This report by Committee 6 of the Council is an extensive update of a previous report on the exposure of the US population to ionizing radiation sources from data gathered in the 1980s (published as Report 93 in 1987). It is combined with an update on the more in-depth assessment of data on medical exposures previously reported in 1989 (Report 100). Individual chapters in this new report are dedicated to specific sources of exposure to the US population—both from natural and artificial radiation—and the level of detail in each chapter is intended to reflect the significance of the contribution of each source to the total collective dose of the population. The first chapter is on the most significant contributor: background radiation. It expands on the concept of natural background radiation in Report 93, renaming it 'ubiquitous background', and describing in detail the contributions from both extra-terrestrial and terrestrial sources. The data demonstrates that the average dose from such exposure has varied little since the previous report (a slight increase from 3.0 mSv to 3.1 mSv). The next chapter is on medical radiation, i.e. the exposure to the population when attending as patients, not including occupational exposure to hospital workers. The most striking data published in the entire report is the increase in the contribution to the total US population dose attributed to such medical exposures. It is now as significant as that from background radiation: medical exposures now account for an average effective dose to the US citizen of 3.00 mSv, up from 0.53 mSv in 1992 (Report 100). The most important contribution to this increase is the 1.46 mSv from CT scanning alone. The nuclear medicine (including PET) contribution is up from 0.14 mSv to 0.77mSv. This evidently must be due to significant changes in medical radiological practice in the US tied to the increase in the availability of CT and PET imaging facilities. These increasing contributions have driven

Internal migration and urbanization in China: impacts on population exposure to household air pollution (2000-2010).

PubMed

Aunan, Kristin; Wang, Shuxiao

2014-05-15

Exposure to fine particles ≤ 2.5 μm in aerodynamic diameter (PM2.5) from incomplete combustion of solid fuels in household stoves, denoted household air pollution (HAP), is a major contributor to ill health in China and globally. Chinese households are, however, undergoing a massive transition to cleaner household fuels. The objective of the present study is to establish the importance of internal migration when it comes to the changing household fuel use pattern and the associated exposure to PM2.5 for the period 2000 to 2010. We also estimate health benefits of the fuel transition in terms of avoided premature deaths. Using China Census data on population, migration, and household fuel use for 2000 and 2010 we identify the size, place of residence, and main cooking fuel of sub-populations in 2000 and 2010, respectively. We combine these data with estimated exposure levels for the sub-populations and estimate changes in population exposure over the decade. We find that the population weighted exposure (PWE) for the Chinese population as a whole was reduced by 52 (36-70) μg/m(3) PM2.5 over the decade, and that about 60% of the reduction can be linked to internal migration. During the same period the migrant population, in total 261 million people, was subject to a reduced population weighted exposure (ΔPWE) of 123 (87-165) μg/m(3) PM2.5. The corresponding figure for non-migrants is 34 (23-47) μg/m(3). The largest ΔPWE was estimated for rural-to-urban migrants (138 million people), 214 (154-283) μg/m(3). The estimated annual health benefit associated with the reduced exposure in the total population is 31 (26-37) billion USD, corresponding to 0.4% of the Chinese GDP. Copyright © 2014 Elsevier B.V. All rights reserved.

Infection prevention and control during prolonged human space travel.

PubMed

Mermel, Leonard A

2013-01-01

Prolonged human spaceflight to another planet or an asteroid will introduce unique challenges of mitigating the risk of infection. During space travel, exposure to microgravity, radiation, and stress alter human immunoregulatory responses, which can in turn impact an astronaut's ability to prevent acquisition of infectious agents or reactivation of latent infection. In addition, microgravity affects virulence, growth kinetics, and biofilm formation of potential microbial pathogens. These interactions occur in a confined space in microgravity, providing ample opportunity for heavy microbial contamination of the environment. In addition, there is the persistence of aerosolized, microbe-containing particles. Any mission involving prolonged human spaceflight must be carefully planned to minimize vulnerabilities and maximize the likelihood of success.

Econometric model for age- and population-dependent radiation exposures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sandquist, G.M.; Slaughter, D.M.; Rogers, V.C.

1991-01-01

The economic impact associated with ionizing radiation exposures in a given human population depends on numerous factors including the individual's mean economic status as a function age, the age distribution of the population, the future life expectancy at each age, and the latency period for the occurrence of radiation-induced health effects. A simple mathematical model has been developed that provides an analytical methodology for estimating the societal econometrics associated with radiation effects are to be assessed and compared for economic evaluation.

Prolonged exposure therapy for the treatment of patients diagnosed with psychogenic non-epileptic seizures (PNES) and post-traumatic stress disorder (PTSD).

PubMed

Myers, Lorna; Vaidya-Mathur, Urmi; Lancman, Marcelo

2017-01-01

Although there is general consensus that psychogenic non-epileptic seizures (PNES) are treated with psychotherapy, the effectiveness of most psychotherapeutic modalities remains understudied. In this treatment series of 16 patients dually diagnosed with PNES and post-traumatic stress disorder (PTSD), we evaluated the effect of prolonged exposure therapy (PE) on reduction of PNES. Secondary measures included Beck Depression Inventory (BDI-II) and Post-Traumatic Disorder Diagnostic Scale (PDS). Subjects diagnosed with video EEG-confirmed PNES and PTSD confirmed through neuropsychological testing and clinical interview were treated with traditional PE psychotherapy with certain modifications for the PNES. Treatment was conducted over the course of 12-15 weekly sessions. Seizure frequency was noted in each session by examining the patients' seizure logs, and mood and PTSD symptomatology was assessed at baseline and on the final session. Eighteen subjects enrolled, and 16 (88.8%) completed the course of treatment. Thirteen of the 16 (81.25%) therapy completers reported no seizures by their final PE session, and the other three reported a decline in seizure frequency (Z=-3.233, p=0.001). Mean scores on scales of depression (M=-13.56, SD=12.27; t (15)=-4.420, p<0,001) and PTSD symptoms (M=-17.1875, SD=13.01; t (15)=-5.281, p<0.001) showed significant improvement from baseline to final session. Longitudinal seizure follow up in 14 patients revealed that gains made on the final session were maintained at follow-up (Z=-1.069 p=0.285). Prolonged exposure therapy for patients dually diagnosed with PNES and PTSD reduced the number of PNES and improved mood and post traumatic symptomatology. Follow-up revealed that gains made in seizure control on the last day of treatment were maintained over time. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Population exposure to hazardous air quality due to the 2015 fires in Equatorial Asia.

PubMed

Crippa, P; Castruccio, S; Archer-Nicholls, S; Lebron, G B; Kuwata, M; Thota, A; Sumin, S; Butt, E; Wiedinmyer, C; Spracklen, D V

2016-11-16

Vegetation and peatland fires cause poor air quality and thousands of premature deaths across densely populated regions in Equatorial Asia. Strong El-Niño and positive Indian Ocean Dipole conditions are associated with an increase in the frequency and intensity of wildfires in Indonesia and Borneo, enhancing population exposure to hazardous concentrations of smoke and air pollutants. Here we investigate the impact on air quality and population exposure of wildfires in Equatorial Asia during Fall 2015, which were the largest over the past two decades. We performed high-resolution simulations using the Weather Research and Forecasting model with Chemistry based on a new fire emission product. The model captures the spatio-temporal variability of extreme pollution episodes relative to space- and ground-based observations and allows for identification of pollution sources and transport over Equatorial Asia. We calculate that high particulate matter concentrations from fires during Fall 2015 were responsible for persistent exposure of 69 million people to unhealthy air quality conditions. Short-term exposure to this pollution may have caused 11,880 (6,153-17,270) excess mortalities. Results from this research provide decision-relevant information to policy makers regarding the impact of land use changes and human driven deforestation on fire frequency and population exposure to degraded air quality.

Population exposure to hazardous air quality due to the 2015 fires in Equatorial Asia

PubMed Central

Crippa, P.; Castruccio, S.; Archer-Nicholls, S.; Lebron, G. B.; Kuwata, M.; Thota, A.; Sumin, S.; Butt, E.; Wiedinmyer, C.; Spracklen, D. V.

2016-01-01

Vegetation and peatland fires cause poor air quality and thousands of premature deaths across densely populated regions in Equatorial Asia. Strong El-Niño and positive Indian Ocean Dipole conditions are associated with an increase in the frequency and intensity of wildfires in Indonesia and Borneo, enhancing population exposure to hazardous concentrations of smoke and air pollutants. Here we investigate the impact on air quality and population exposure of wildfires in Equatorial Asia during Fall 2015, which were the largest over the past two decades. We performed high-resolution simulations using the Weather Research and Forecasting model with Chemistry based on a new fire emission product. The model captures the spatio-temporal variability of extreme pollution episodes relative to space- and ground-based observations and allows for identification of pollution sources and transport over Equatorial Asia. We calculate that high particulate matter concentrations from fires during Fall 2015 were responsible for persistent exposure of 69 million people to unhealthy air quality conditions. Short-term exposure to this pollution may have caused 11,880 (6,153–17,270) excess mortalities. Results from this research provide decision-relevant information to policy makers regarding the impact of land use changes and human driven deforestation on fire frequency and population exposure to degraded air quality. PMID:27848989

Hip pain onset in relation to cumulative workplace and leisure time mechanical load: a population based case-control study.

PubMed

Pope, D P; Hunt, I M; Birrell, F N; Silman, A J; Macfarlane, G J

2003-04-01

In an unselected community sample of adults, to assess the role and importance of exposure to mechanical factors both at work and leisure in the aetiology of hip pain. A population based prevalence case-control study. Cases and controls were identified from a population survey of 3847 subjects registered with two general practices in Cheshire, United Kingdom. All subjects received a postal questionnaire which inquired about hip pain during the past month. An occupational history was obtained, including exposure to each of seven physical demands. Information was also obtained on history of participation in eight common sporting activities. 88% of those invited to participate returned a completed questionnaire. The 352 subjects with hip pain were designated as cases, and the remaining 3002 subjects as controls. In people ever employed, hip pain was significantly associated with high cumulative workplace exposure (before onset) of walking long distances over rough ground, lifting/moving heavy weights, sitting for prolonged periods, walking long distances, frequent jumping between different levels, and standing for prolonged periods. Odds ratios (ORs) in the higher exposure categories ranged from 1.46 to 2.65. Cumulative exposure to three sporting activities was significantly associated with hip pain: track and field sports, jogging, and walking, with odds ratios varying between 1.57 to 1.94. On multivariate analysis three factors were independent predictors of hip pain onset: cumulative exposure of sitting for prolonged periods (higher exposure v not exposed: OR=1.82, 95% confidence interval (CI) 1.13 to 2.92), lifting weights >50 lb (23 kg) (OR=1.74, 95% CI 1.06 to 2.86) (both relating to the workplace), and walking as a leisure activity (OR=1.97, 95% CI 1.32 to 2.94). The population attributable risk associated with each of these activities was 21%, 13%, and 16%, respectively Cumulative exposure to some workplace and sporting "mechanical" risk factors for hip

Value of Formalin Fixation for the Prolonged Preservation of Rodent Myocardial Microanatomical Organization: Evidence by MR Diffusion Tensor Imaging.

PubMed

Giannakidis, Archontis; Gullberg, Grant T; Pennell, Dudley J; Firmin, David N

2016-07-01

Previous ex vivo diffusion tensor imaging (DTI) studies on formalin-fixed myocardial tissue assumed that, after some initial changes in the first 48 hr since the start of fixation, DTI parameters remain stable over time. Prolonged preservation of cardiac tissue in formalin prior to imaging has been seen many times in the DTI literature as it is considered orderly. Our objective is to define the effects of the prolonged cardiac tissue exposure to formalin on tissue microanatomical organization, as this is assessed by DTI parameters. DTI experiments were conducted on eight excised rodent hearts that were fixed by immersion in formalin. The samples were randomly divided into two equinumerous groups corresponding to shorter (∼2 weeks) and more prolonged (∼6-8 weeks) durations of tissue exposure to formalin prior to imaging. We found that when the duration of cardiac tissue exposure to formalin before imaging increased, water diffusion became less restricted, helix angle (HA) histograms flattened out and exhibited heavier tails (even though the classic HA transmural variation was preserved), and a significant loss of inter-voxel primary diffusion orientation integrity was introduced. The prolonged preservation of cardiac tissue in formalin profoundly affected its microstructural organization, as this was assessed by DTI parameters. The accurate interpretation of diffusivity profiles necessitates awareness of the pitfalls of prolonged cardiac tissue exposure duration to formalin. The acquired knowledge works to the advantage of a proper experimental design of DTI studies of fixed hearts. Anat Rec, 299:878-887, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Factors on working conditions and prolonged fatigue among physicians in Japan.

PubMed

Wada, Koji; Arimatsu, Mayuri; Yoshikawa, Toru; Oda, Susumu; Taniguchi, Hatsumi; Higashi, Toshiaki; Aizawa, Yoshiharu

2008-10-01

Fatigue among physicians could affect patients' safety and physicians' health. Fatigue could be caused by unfavorable working conditions. However, there have been no studies on the working conditions and fatigue among physicians in Japan. The objective of this study was to determine the factors on working conditions associated with prolonged fatigue among physicians in Japan. A questionnaire was mailed to physicians who graduated from one of the medical schools in Japan and who have had more than 3 years of experience in clinical practice. They were asked to assess 10 different aspects of their working conditions using a 5-point Likert scale. Prolonged fatigue was measured using the checklist of individual strength questionnaire. Multiple regression analysis was used to examine the multivariate relationship between the variables and prolonged fatigue. Data from 377 men and 101 women were analyzed in this study. For both male and female physicians, a harder workload was positively associated and better career satisfaction was negatively associated with prolonged fatigue. Prolonged fatigue was negatively associated with better relationships with other physicians and staff for male physicians and less personal time for female physicians. The adjusted variance in prolonged fatigue related to exposure variables was 26 and 29% in men and in women, respectively. The result of this study suggested that it is desirable to take these factors into consideration in the management of prolonged fatigue among physicians in Japan.

[Causation between occupational prolonged standing time during progestation and pregnancy related complications].

PubMed

Weng, Ting-ting; Xu, Ye-qing; Yan, Shuang-qin; Pan, Wei-jun; Tao, Fang-biao

2013-06-01

To describe the epidemiological characteristics of profession related long-standing behavior during preconception and progestation, and to probe the relationship between prolonged standing jobs and the common pregnancy related complications among pregnant women, in Ma' anshan city,Anhui province. In this cohort study, subjects who had their first antenatal examination at Ma' anshan Maternal and Child Care Centers were recruited under informed consent, from October 2008 to October 2010. All the information were collected through questionnaires in the first, second and third trimesters respectively. Three questionnaires were filled in by subjects under the guidance of healthcare takers. In the study, the 75(th) percentile of prolonged-standing times were 4.0 h/d and 3.0 h/d respectively in preconception and progestation. The characteristics of pregnant women with low social/economic status, prone to be involved in stand-long occupation. Results in logistic regression analysis, prolonged-standing jobs during preconception was the risk factor of pregnancy-induced hypertension and severe anemia. The adjusted odds ratios were 2.05 (95%CI:1.26-3.31) and 1.38(95%CI:1.03-1.85)respectively. Prolonged standing jobs appeared to be common occupational exposure to and risks of both pregnant woman and their fetus. Exposure to these kinds of jobs during preconception could increase the risk of pregnancy-induced hypertension and severe anemia. In order to promote maternal health programs, all the related occupational risk factors should be valued and avoided during preconception and pregnancy.

Neural circuits via which single prolonged stress exposure leads to fear extinction retention deficits

PubMed Central

Stanfield, Briana R.; Staib, Jennifer M.; David, Nina P.; Keller, Samantha M.; DePietro, Thomas

2016-01-01

Single prolonged stress (SPS) has been used to examine mechanisms via which stress exposure leads to post-traumatic stress disorder symptoms. SPS induces fear extinction retention deficits, but neural circuits critical for mediating these deficits are unknown. To address this gap, we examined the effect of SPS on neural activity in brain regions critical for extinction retention (i.e., fear extinction circuit). These were the ventral hippocampus (vHipp), dorsal hippocampus (dHipp), basolateral amygdala (BLA), prelimbic cortex (PL), and infralimbic cortex (IL). SPS or control rats were fear conditioned then subjected to extinction training and testing. Subsets of rats were euthanized after extinction training, extinction testing, or immediate removal from the housing colony (baseline condition) to assay c-Fos levels (measure of neural activity) in respective brain region. SPS induced extinction retention deficits. During extinction training SPS disrupted enhanced IL neural activity and inhibited BLA neural activity. SPS also disrupted inhibited BLA and vHipp neural activity during extinction testing. Statistical analyses suggested that SPS disrupted functional connectivity within the dHipp during extinction training and increased functional connectivity between the BLA and vHipp during extinction testing. Our findings suggest that SPS induces extinction retention deficits by disrupting both excitatory and inhibitory changes in neural activity within the fear extinction circuit and inducing changes in functional connectivity within the Hipp and BLA. PMID:27918273

Socio-demographic patterns of posttraumatic stress disorder in Medellin, Colombia and the context of lifetime trauma exposure

PubMed Central

Gaviria, Silvia Lucia; Espinola, Maria; Restrepo, Diana; Lotero, Juliana; Berbesi, Dedsy Y.; Sierra, Gloria Maria; Chaskel, Roberto; Espinel, Zelde; Shultz, James M.

2016-01-01

ABSTRACT Colombia, South America is currently transitioning to post-conflict status following 6 decades of armed conflict. The population has experienced extensive exposures to potentially traumatic events throughout the lifespan. Sources of trauma exposure include the prolonged armed insurgency, narco-trafficking violence, urban gang violence, violent actions of criminal bands, intra-familial violence, gender-based violence, and sex trafficking. Exposure to potentially traumatic events is related to a variety of psychiatric outcomes, in particular, posttraumatic stress disorder. Given this context of lifetime trauma exposure, socio-demographic patterns of posttraumatic stress disorder were explored in a sample of residents of Medellin, Colombia, the nation's second largest city and a nexus for multiple types of trauma exposure. PMID:28265488

Surgery for subacromial impingement syndrome in relation to intensities of occupational mechanical exposures across 10-year exposure time windows.

PubMed

Dalbøge, Annett; Frost, Poul; Andersen, Johan Hviid; Svendsen, Susanne Wulff

2018-03-01

We aimed to identify intensities of occupational mechanical exposures (force, arm elevation and repetition) that do not entail an increased risk of surgery for subacromial impingement syndrome (SIS) even after prolonged durations of exposure. Additionally, we wanted to evaluate if exposure to hand-arm vibration (HAV) is an independent risk factor. We used data from a register-based cohort study of the entire Danish working population (n=2 374 403). During follow-up (2003-2008), 14 118 first-time events of surgery for SIS occurred. For each person, we linked register-based occupational codes (1993-2007) to a general population job exposure matrix to obtain year-by-year exposure intensities on measurement scales for force, upper arm elevation >90° and repetition and expert rated intensities of exposure to HAV. For 10-year exposure time windows, we calculated the duration of exposure at specific intensities above minimal (low, medium and high). We used a logistic regression technique equivalent to discrete survival analysis adjusting for cumulative effects of other mechanical exposures. We found indications of safe exposure intensities for repetition (median angular velocity <45°/s), while force exertion ≥10% of maximal voluntary electrical activity and upper arm elevation >90° >2 min/day implied an increased risk reaching ORs of 1.7 and 1.5 after 10 years at low intensities. No associations were found for HAV. We found indications of safe exposure intensities for repetition. Any intensities of force and upper arm elevation >90° above minimal implied an increased risk across 10-year exposure time windows. No independent associations were found for HAV. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

A POPULATION EXPOSURE MODEL FOR PARTICULATE MATTER: CASE STUDY RESULTS FOR PM 2.5 IN PHILADELPHIA, PA

EPA Science Inventory

A population exposure model for particulate matter (PM), called the Stochastic Human Exposure and Dose Simulation (SHEDS-PM) model, has been developed and applied in a case study of daily PM2.5 exposures for the population living in Philadelphia, PA. SHEDS-PM is a probabilisti...

IONIZING RADIATION EXPOSURE OF THE POPULATION OF THE U.S.

EPA Science Inventory

This report updates information published by the National Council on Radiation Protection and Measurements (NCRP) in 1987. NCRP reports are considered the authoritative reference for the sources and magnitude of average background exposure to the U.S. population.

Development of and Selected Performance Characteristics of CANJEM, a General Population Job-Exposure Matrix Based on Past Expert Assessments of Exposure.

PubMed

Sauvé, Jean-François; Siemiatycki, Jack; Labrèche, France; Richardson, Lesley; Pintos, Javier; Sylvestre, Marie-Pierre; Gérin, Michel; Bégin, Denis; Lacourt, Aude; Kirkham, Tracy L; Rémen, Thomas; Pasquet, Romain; Goldberg, Mark S; Rousseau, Marie-Claude; Parent, Marie-Élise; Lavoué, Jérôme

2018-06-12

We developed a job-exposure matrix called CANJEM using data generated in population-based case-control studies of cancer. This article describes some of the decisions in developing CANJEM, and some of its performance characteristics. CANJEM is built from exposure information from 31673 jobs held by study subjects included in our past case-control studies. For each job, experts had evaluated the intensity, frequency, and likelihood of exposure to a predefined list of agents based on jobs histories and descriptions of tasks and workplaces. The creation of CANJEM involved a host of decisions regarding the structure of CANJEM, and operational decisions regarding which parameters to present. The goal was to produce an instrument that would provide great flexibility to the user. In addition to describing these decisions, we conducted analyses to assess how well CANJEM covered the range of occupations found in Canada. Even at quite a high level of resolution of the occupation classifications and time periods, over 90% of the recent Canadian working population would be covered by CANJEM. Prevalence of exposure of specific agents in specific occupations ranges from 0% to nearly 100%, thereby providing the user with basic information to discriminate exposed from unexposed workers. Furthermore, among exposed workers there is information that can be used to discriminate those with high exposure from those with low exposure. CANJEM provides good coverage of the Canadian working population and possibly that of several other countries. Available in several occupation classification systems and including 258 agents, CANJEM can be used to support exposure assessment efforts in epidemiology and prevention of occupational diseases.

Prenatal nicotinic exposure prolongs superior laryngeal C-fiber-mediated apnea and bradycardia through enhancing neuronal TRPV1 expression and excitation.

PubMed

Gao, Xiuping; Zhao, Lei; Zhuang, Jianguo; Zang, Na; Xu, Fadi

2017-10-01

Maternal cigarette smoke, including prenatal nicotinic exposure (PNE), is responsible for sudden infant death syndrome (SIDS). The fatal events of SIDS are characterized by severe bradycardia and life-threatening apneas. Although activation of transient receptor potential vanilloid 1 (TRPV1) of superior laryngeal C fibers (SLCFs) could induce bradycardia and apnea and has been implicated in SIDS pathogenesis, how PNE affects the SLCF-mediated cardiorespiratory responses remains unexplored. Here, we tested the hypothesis that PNE would aggravate the SLCF-mediated apnea and bradycardia via up-regulating TRPV1 expression and excitation of laryngeal C neurons in the nodose/jugular (N/J) ganglia. To this end, we compared the following outcomes between control and PNE rat pups at postnatal days 11-14: 1 ) the cardiorespiratory responses to intralaryngeal application of capsaicin (10 µg/ml, 50 µl), a selective stimulant for TRPV1 receptors, in anesthetized preparation; 2 ) immunoreactivity and mRNA of TRPV1 receptors of laryngeal sensory C neurons in the N/J ganglia retrogradely traced by 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate; and 3 ) TRPV1 currents and electrophysiological characteristics of these neurons by using whole-cell patch-clamp technique in vitro Our results showed that PNE markedly prolonged the apneic response and exacerbated the bradycardic response to intralaryngeal perfusion of capsaicin, which was associated with up-regulation of TRPV1 expression in laryngeal C neurons. In addition, PNE increased the TRPV1 currents, depressed the slow delayed rectifier potassium currents, and increased the resting membrane potential of these neurons. Our results suggest that PNE is capable of aggravating the SLCF-mediated apnea and bradycardia through TRPV1 sensitization and neuronal excitation, which may contribute to the pathogenesis of SIDS.-Gao, X., Zhao, L., Zhuang, J., Zang, N., Xu, F. Prenatal nicotinic exposure prolongs superior

Probabilistic estimation of residential air exchange rates for population-based human exposure modeling

EPA Science Inventory

Residential air exchange rates (AERs) are a key determinant in the infiltration of ambient air pollution indoors. Population-based human exposure models using probabilistic approaches to estimate personal exposure to air pollutants have relied on input distributions from AER meas...

Changes in exposure to ‘life stressors’ in the Aboriginal and Torres Strait Islander population, 2002 to 2008

PubMed Central

2014-01-01

Background The Negative Life Events Scale (NLES) has been included in nationally representative surveys of the Indigenous and Australian population since 2002 as a measure of exposure to a range of ‘life stressors’. There has been limited reporting or analysis of estimates of the NLES from these surveys. This paper reports changes in exposure to stressors from 2002 to 2008 for the Indigenous population, and examines inter-relationships between eleven NLES items. Data for the 2006 Australian population is also included for comparative purposes. Methods Data from the 2002 and 2008 National Aboriginal and Torres Strait Islander Social Surveys (NATSISS) and the 2006 General Social Survey (GSS) were accessed from the Australia Bureau of Statistics in order to determine significant changes in exposure to stressors for the 2002 and 2008 Indigenous population by remoteness and to compare this with the 2006 Australian population. Factor analysis was used to assess the inter-relationships between stressors for the Indigenous and Australian population by remoteness. Results In remote locations, between 2002 and 2008, exposure to life stressors decreased significantly for the Indigenous population across seven of the eleven stressors. In non-remote locations, exposure to four of the stressors increased significantly. Exposure to stressors in the 2002 and 2008 non-remote Indigenous population were significantly higher than those for the 2006 Australian population for all items, except ‘alcohol and/or drug problems’ and ‘trouble with the police’, which showed no evidence of a difference. The factor analysis of the NLES for the 2002 and 2008 remote and non-remote Indigenous populations and the 2006 Australian population showed a consistent clustering of items into three groups: social transgressions; grief and trauma; and labour market stressors. Conclusions The reduction in exposure to life stressors for the remote Indigenous population may be related to policy and

“How Will It Help Me?”: Reasons Underlying Treatment Preferences Between Sertraline and Prolonged Exposure in PTSD

PubMed Central

Chen, Jessica A.; Keller, Stephanie M.; Zoellner, Lori A.; Feeny, Norah C.

2014-01-01

Individuals with posttraumatic stress disorder (PTSD) often wait years before seeking treatment. Improving treatment initiation and adherence requires a better understanding patient beliefs that lead to treatment preferences. Using a treatment-seeking sample (N = 200) with chronic PTSD, qualitative reasons underlying treatment preferences for either prolonged exposure (PE) or sertraline (SER) were examined. Reasons for treatment preference primarily focused on how the treatment was perceived to reduce PTSD symptoms rather than practical ones. Patients were more positive about PE than SER. Individual differences did not reliably predict underlying preference reasons, suggesting that what makes a treatment desirable is not strongly determined by current functioning, treatment, or trauma history. Taken together, this information is critical for treatment providers, arguing for enhancing psychoeducation about how treatment works and acknowledging pre-existing biases against pharmacotherapy for PTSD that should be addressed. This knowledge has the potential to optimize and better personalize PTSD patient care. PMID:23896851

The analysis of QT interval and repolarization morphology of the heart in chronic exposure to lead.

PubMed

Kiełtucki, J; Dobrakowski, M; Pawlas, N; Średniawa, B; Boroń, M; Kasperczyk, S

2017-10-01

There are no common recommendations regarding electrocardiographic monitoring in occupationally exposed workers. Therefore, the present study was designed to investigate whether exposure to lead results in an increase of selected electrocardiography (ECG) pathologies, such as QT interval prolongation and repolarization disorders, in occupationally exposed workers. The study group included 180 workers occupationally exposed to lead compounds. The exposed group was divided according to the median of the mean blood lead level (PbB mean ) calculated based on a series of measurements performed during 5-year observation period (35 µg/dl) into two subgroups: low exposure (LE, PbB mean = 20.0-35.0 µg/dl) and high exposure (HE, PbB mean = 35.1-46.4 µg/dl). The control group consisted of 69 healthy workers without occupational exposure to lead. ECG evaluation included the analysis of heart rate (HR), QT interval and repolarization abnormalities. Mean QT interval was significantly greater in the exposed population than in the control group by 2%. In the HE group, mean QT interval was significantly greater than in the control group by 4% and significantly different from those noted in the LE group. Positive correlations between QT interval and lead exposure indices were also reported. Besides, there was a negative correlation between HR and blood lead level. Increased concentration of lead in the blood above 35 μg/dl is associated with the QT interval prolongation, which may trigger arrhythmias when combined with other abnormalities, such as long QT syndrome. Therefore, electrocardiographic evaluation should be a part of a routine monitoring of occupationally exposed populations.

Reinventing the Wheel: Impact of Prolonged Antibiotic Exposure on Multi-Drug Resistant Ventilator-Associated Pneumonia in Trauma Patients.

PubMed

Lewis, Richard H; Sharpe, John P; Swanson, Joseph M; Fabian, Timothy C; Croce, Martin A; Magnotti, Louis J

2018-04-16

Multi-drug resistant (MDR) strains of both Acinetobacter baumannii (AB) and Pseudomonas aeruginosa (PA) as causative VAP pathogens are becoming increasingly common. Still, the risk factors associated with this increased resistance have yet to be elucidated. The purpose of this study was to examine the changing sensitivity patterns of these pathogens over time and determine which risk factors predict MDR in trauma patients with VAP. Patients with either AB or PA VAP over 10 years were stratified by pathogen sensitivity (sensitive (SEN) and MDR), age, severity of shock and injury severity. Prophylactic and empiric antibiotic days, risk factors for severe VAP and mortality were compared. Multivariable logistic regression (MLR) was performed to determine which risk factors were independent predictors of MDR. 397 patients were identified with AB or PA VAP. There were 173 episodes of AB (91 SEN and 82 MDR) and 224 episodes of PA (170 SEN and 54 MDR). The incidence of MDR VAP did not change over the study (p=0.633). Groups were clinically similar with the exception of 24-hour transfusions (14 vs 19 units, p = 0.009) and extremity AIS (1 vs 3, p<0.001), both significantly increased in the MDR group. Antibiotic exposure as well as mIEAT (63% vs 81%, p<0.001) were significantly increased in the MDR group. MLR identified prophylactic antibiotic days (OR 23.1; 95%CI 16.7-28, p<0.001) and mIEAT (OR 18.1; 95%CI 12.2-26.1, p=0.001) as independent predictors of MDR after adjusting for severity of shock, injury severity, severity of VAP and antibiotic exposure. Prolonged exposure to unnecessary antibiotics remains one of the strongest predictors for the development of antibiotic resistance. MLR identified prophylactic antibiotic days and mIEAT an independent risk factors for MDR VAP. Thus, limiting prophylactic antibiotic days is the only potentially modifiable risk factor for the development of MDR VAP in trauma patients. Level III, Prognostic LEVEL OF EVIDENCE: Multi

Probabilistic exposure assessment to face and oral care cosmetic products by the French population.

PubMed

Bernard, A; Dornic, N; Roudot, Ac; Ficheux, As

2018-01-01

Cosmetic exposure data for face and mouth are limited in Europe. The aim of the study was to assess the exposure to face cosmetics using recent French consumption data (Ficheux et al., 2016b, 2015). Exposure was assessed using a probabilistic method for thirty one face products from four lines of products: cleanser, care, make-up and make-up remover products and two oral care products. Probabilistic exposure was assessed for different subpopulation according to sex and age in adults and children. Pregnant women were also studied. The levels of exposure to moisturizing cream, lip balm, mascara, eyeliner, cream foundation, toothpaste and mouthwash were higher than the values currently used by the Scientific Committee on Consumer Safety (SCCS). Exposure values found for eye shadow, lipstick, lotion and milk (make-up remover) were lower than SCCS values. These new French exposure values will be useful for safety assessors and for safety agencies in order to protect the general population and the at risk populations. Copyright © 2017. Published by Elsevier Ltd.

Pathogen exposure and blood chemistry in the Washington population of northern sea otters (Enhydra lutris kenyoni)

USGS Publications Warehouse

White, C. LeAnn; Schuler, Krysten L.; Thomas, Nancy J.; Webb, Julie L.; Saliki, Jeremiah T.; Ip, Hon S.; Dubey, J.P.; Frame, Elizabeth R.

2013-01-01

Northern sea otters (Enhydra lutris kenyoni) from Washington State, United States were evaluated in 2011 to determine health status and pathogen exposure. Antibodies to Brucella spp. (10%) and influenza A virus (23%) were detected for the first time in this population in 2011. Changes in clinical pathology values (serum chemistries), exposure to pathogens, and overall health of the population over the last decade were assessed by comparing 2011 data to the data collected on this population in 2001–2002. Several serum chemistry parameters were different between study years and sexes but were not clinically significant. The odds of canine distemper virus exposure were higher for otters sampled in 2001–2002 (80%) compared to 2011 (10%); likelihood of exposure significantly increased with age. Prevalence of exposure to Sarcocystis neurona was also higher in 2001–2002 (29%) than in 2011 (0%), but because testing methods varied between study years the results were not directly comparable. Exposure to Leptospira spp. was only observed in 2001–2002. Odds of Toxoplasma gondii exposure were higher for otters sampled in 2011 (97%) than otters in 2001–2002 (58%). Substantial levels of domoic acid (n = 2) and saxitoxin (n = 2) were found in urine or fecal samples from animals sampled in 2011. No evidence of calicivirus or Coxiella burnetii exposure in the Washington population of northern sea otters was found in either 2001–2002 or 2011. Changes in exposure status from 2001–2002 to 2011 suggest that the Washington sea otter population may be dealing with new disease threats (e.g., influenza) while also increasing their susceptibility to diseases that may be highly pathogenic in naïve individuals (e.g., canine distemper).

Predicting QT prolongation in humans during early drug development using hERG inhibition and an anaesthetized guinea-pig model

PubMed Central

Yao, X; Anderson, D L; Ross, S A; Lang, D G; Desai, B Z; Cooper, D C; Wheelan, P; McIntyre, M S; Bergquist, M L; MacKenzie, K I; Becherer, J D; Hashim, M A

2008-01-01

Background and purpose: Drug-induced prolongation of the QT interval can lead to torsade de pointes, a life-threatening ventricular arrhythmia. Finding appropriate assays from among the plethora of options available to predict reliably this serious adverse effect in humans remains a challenging issue for the discovery and development of drugs. The purpose of the present study was to develop and verify a reliable and relatively simple approach for assessing, during preclinical development, the propensity of drugs to prolong the QT interval in humans. Experimental approach: Sixteen marketed drugs from various pharmacological classes with a known incidence—or lack thereof—of QT prolongation in humans were examined in hERG (human ether a-go-go-related gene) patch-clamp assay and an anaesthetized guinea-pig assay for QT prolongation using specific protocols. Drug concentrations in perfusates from hERG assays and plasma samples from guinea-pigs were determined using liquid chromatography-mass spectrometry. Key results: Various pharmacological agents that inhibit hERG currents prolong the QT interval in anaesthetized guinea-pigs in a manner similar to that seen in humans and at comparable drug exposures. Several compounds not associated with QT prolongation in humans failed to prolong the QT interval in this model. Conclusions and implications: Analysis of hERG inhibitory potency in conjunction with drug exposures and QT interval measurements in anaesthetized guinea-pigs can reliably predict, during preclinical drug development, the risk of human QT prolongation. A strategy is proposed for mitigating the risk of QT prolongation of new chemical entities during early lead optimization. PMID:18587422

Fox smell abrogates the effect of herbal odor to prolong mouse cardiac allograft survival.

PubMed

Jin, Xiangyuan; Uchiyama, Masateru; Zhang, Qi; Niimi, Masanori

2014-05-09

Herbal medicines have unique odors, and the act of smelling may have modulatory effects on the immune system. We investigated the effect of olfactory exposure to Tokishakuyaku-san (TJ-23), a Japanese herbal medicine, on alloimmune responses in a murine model of cardiac allograft transplantation. Naïve or olfactory-dysfunctional CBA mice underwent transplantation of a C57BL/6 heart and were exposed to the odor of TJ-23 until rejection. Some naïve CBA recipients of an allograft were given olfactory exposure to Sairei-to (TJ-114), trimethylthiazoline (TMT), individual components of TJ-23, or a TJ-23 preparation lacking one component. Adoptive transfer studies were performed to determine whether regulatory cells were generated. Untreated CBA mice rejected their C57BL/6 allografts acutely, as did olfactory-dysfunctional CBA mice exposed to the odor of TJ-23. CBA recipients of a C57BL/6 heart given olfactory exposure to TJ-23 had significantly prolonged allograft survival, whereas those exposed to the odor of TJ-114, TMT, one component of TJ-23, or TJ-23 lacking a component did not. Secondary allograft recipients that were given, at 30 days after transplantation, either whole splenocytes, CD4+ cells, or CD4+CD25+ cells from primary recipients exposed to the odor of TJ-23 had indefinitely prolonged allograft survival. Prolonged survival of cardiac allografts and generation of regulatory cells was associated with exposure to the odor of TJ-23 in our model. The olfactory area of the brain may have a role in the modulation of immune responses.

Changes in Negative Cognitions Mediate PTSD Symptom Reductions During Client-Centered Therapy and Prolonged Exposure for Adolescents

PubMed Central

McLean, Carmen P.; Yeh, Rebecca; Rosenfield, David; Foa, Edna B.

2015-01-01

Objective To assess whether changes in negative trauma-related cognitions play an important role in reducing symptoms of posttraumatic stress disorder (PTSD) and depression during prolonged exposure therapy for adolescents (PE-A). Method Secondary analysis of data from a randomized controlled trial comparing PE-A with client-centered therapy (CCT) for PTSD. Participants were 61 adolescent female sexual assault survivors ages 13–18 who received 8–14 weekly sessions of PE-A or CCT at a community rape crisis center. PTSD severity was assessed at baseline, mid-treatment, post-treatment, and 3-months post-treatment. Participants also completed self-report measures of negative posttraumatic cognitions and depressive symptoms at the same assessment points. Results Cross lag panel mediation analyses showed that change in negative trauma-related cognitions mediated change in PTSD symptoms and depressive symptoms whereas change in PTSD and depressive symptoms did not mediate change in negative cognitions. Conclusion Our findings support EPT and suggest that change in negative trauma-related cognitions is a mechanism of both PE-A and CCT. PMID:25812826

Factors affecting outdoor exposure in winter: population-based study

NASA Astrophysics Data System (ADS)

Mäkinen, Tiina M.; Raatikka, Veli-Pekka; Rytkönen, Mika; Jokelainen, Jari; Rintamäki, Hannu; Ruuhela, Reija; Näyhä, Simo; Hassi, Juhani

2006-09-01

The extent of outdoor exposure during winter and factors affecting it were examined in a cross-sectional population study in Finland. Men and women aged 25-74 years from the National FINRISK 2002 sub-study ( n=6,591) were queried about their average weekly occupational, leisure-time and total cold exposure during the past winter. The effects of gender, age, area of residence, occupation, ambient temperature, self-rated health, physical activity and education on cold exposure were analysed. The self-reported median total cold exposure time was 7 h/week (8 h men, 6 h women),<1 h/week (2 h men, 0 h women) at work, 4 h/week (5 h men, 4 h women) during leisure time and 1 h/week (1 h men, 1.5 h women) while commuting to work. Factors associated with increased occupational cold exposure among men were: being employed in agriculture, forestry and industry/mining/construction or related occupations, being less educated and being aged 55-64 years. Factors associated with increased leisure-time cold exposure among men were: employment in industry/mining/construction or related occupations, being a pensioner or unemployed, reporting at least average health, being physically active and having college or vocational education. Among women, being a housewife, pensioner or unemployed and engaged in physical activity increased leisure-time cold exposure, and young women were more exposed than older ones. Self-rated health was positively associated with leisure time cold exposure in men and only to a minor extent in women. In conclusion, the subjects reported spending 4% of their total time under cold exposure, most of it (71%) during leisure time. Both occupational and leisure-time cold exposure is greater among men than women.

The validated sun exposure questionnaire: association of objective and subjective measures of sun exposure in a Danish population-based sample.

PubMed

Køster, B; Søndergaard, J; Nielsen, J B; Allen, M; Olsen, A; Bentzen, J

2017-02-01

Few questionnaires used in monitoring sun-related behaviour have been tested for validity. We established the criteria validity of a questionnaire developed for monitoring population sun-related behaviour. During May-August 2013, 664 Danes wore a personal electronic ultraviolet radiation (UVR) dosimeter for 1 week that measured their outdoor time and dose of erythemal UVR exposure. In the following week, they answered a questionnaire on their sun-related behaviour in the measurement week. Outdoor time measured by dosimetry correlated strongly with both outdoor time and the developed exposure scale measured in the questionnaire. Exposure measured in standard erythema dose (SED) by dosimetry correlated strongly with the exposure scale. In a linear regression model of UVR (SED) received, 41% of the variation was explained by skin type, age, week of participation and exposure scale, with exposure scale as the main contributor. The weekly sunburn fraction correlated strongly with the number of ambient sun hours (r = 0·73, P < 0·001). This criteria-validated questionnaire provides evidence of the exposure that the questionnaire aimed to measure. The evidence provided showed a strong link between the objectively measured behaviour and the behaviour measured by this survey construct. The questionnaire is the first validated tool to measure the UVR exposure in a national population-based sample. © 2016 The Authors. British Journal of Dermatology published by John Wiley & Sons Ltd on behalf of British Association of Dermatologists.

Does prolonged cyanide exposure have a diabetogenic effect?

PubMed

Soto-Blanco, B; Sousa, A B; Manzano, H; Guerra, J L; Górniak, S L

2001-04-01

Cyanide exposure through cassava consumption has been associated with the development of malnutrition-related diabetes mellitus (MRDM). However, there are few experimental reproductions of this disease. In the present study 42 rats received 0, 9.0 or 12.0 mg KCN/kg bw/d for 15 d, 26 pigs were dosed with 0, 2.0, 4.0 or 6.0 mg KCN/kg for 74 d, and 34 goats received 0, 0.3, 0.6, 1.2 or 3.0 mg KCN/kg for 5 mo. At the end of each experimental period, plasma samples were obtained for glucose and thiocyanate measurement, and the pancreas was collected for histopathologic study. No significant differences in plasma glucose concentrations occurred between groups. The pancreas had no pathology. Chronic cyanide exposure did not promote diabetogenic effects in rats, swine or goats, suggesting that cyanide is not responsible for MRDM in humans.

Poultry Consumption and Arsenic Exposure in the U.S. Population

PubMed Central

Nigra, Anne E.; Nachman, Keeve E.; Love, David C.; Grau-Perez, Maria; Navas-Acien, Ana

2016-01-01

Background: Arsenicals (roxarsone and nitarsone) used in poultry production likely increase inorganic arsenic (iAs), monomethylarsonic acid (MMA), dimethylarsinic acid (DMA), and roxarsone or nitarsone concentrations in poultry meat. However, the association between poultry intake and exposure to these arsenic species, as reflected in elevated urinary arsenic concentrations, is unknown. Objectives: Our aim was to evaluate the association between 24-hr dietary recall of poultry consumption and arsenic exposure in the U.S. population. We hypothesized first, that poultry intake would be associated with higher urine arsenic concentrations and second, that the association between turkey intake and increased urine arsenic concentrations would be modified by season, reflecting seasonal use of nitarsone. Methods: We evaluated 3,329 participants ≥ 6 years old from the 2003–2010 National Health and Nutrition Examination Survey (NHANES) with urine arsenic available and undetectable urine arsenobetaine levels. Geometric mean ratios (GMR) of urine total arsenic and DMA were compared across increasing levels of poultry intake. Results: After adjustment, participants in the highest quartile of poultry consumption had urine total arsenic 1.12 (95% CI: 1.04, 1.22) and DMA 1.13 (95% CI: 1.06, 1.20) times higher than nonconsumers. During the fall/winter, participants in the highest quartile of turkey intake had urine total arsenic and DMA 1.17 (95% CI: 0.99, 1.39; p-trend = 0.02) and 1.13 (95% CI: 0.99, 1.30; p-trend = 0.03) times higher, respectively, than nonconsumers. Consumption of turkey during the past 24 hr was not associated with total arsenic or DMA during the spring/summer. Conclusions: Poultry intake was associated with increased urine total arsenic and DMA in NHANES 2003–2010, reflecting arsenic exposure. Seasonally stratified analyses by poultry type provide strong suggestive evidence that the historical use of arsenic-based poultry drugs contributed to arsenic

Effectiveness of Prolonged Exposure and Cognitive Processing Therapy for U.S. Veterans With a History of Traumatic Brain Injury.

PubMed

Ragsdale, Katie A; Voss Horrell, Sarah C

2016-10-01

This retrospective analysis of previously existing nonrandomized clinical data examined the effectiveness of completing prolonged exposure (PE) or cognitive processing therapy (CPT) in a sample of 41 U.S. veterans at a Veterans Affairs medical center. The sample included 19 veterans with diagnoses of posttraumatic stress disorder (PTSD) and traumatic brain injury (TBI) and 22 veterans with PTSD only. Diagnostic groups did not significantly differ on PTSD and depression symptom reduction, F(2, 36) = 0.05, p = .951; Pillai's trace = 0.00, partial η 2 = .00. Veterans who completed PE showed greater symptom reduction than those who completed CPT, F(2, 36) = 12.10, p < .001; Pillai's trace = 0.40, partial η 2 = .40, regardless of TBI status. Overall, our results suggested that TBI status should not preclude individuals from being offered trauma-focused PTSD treatment. Copyright © 2016 International Society for Traumatic Stress Studies.

Evaluation of World Population-Weighted Effective Dose due to Cosmic Ray Exposure

PubMed Central

Sato, Tatsuhiko

2016-01-01

After the release of the Report of the United Nations Scientific Committee of the Effects of Atomic Radiation in 2000 (UNSCEAR2000), it became commonly accepted that the world population-weighted effective dose due to cosmic-ray exposure is 0.38 mSv, with a range from 0.3 to 2 mSv. However, these values were derived from approximate projections of altitude and geographic dependences of the cosmic-ray dose rates as well as the world population. This study hence re-evaluated the population-weighted annual effective doses and their probability densities for the entire world as well as for 230 individual nations, using a sophisticated cosmic-ray flux calculation model in tandem with detailed grid population and elevation databases. The resulting world population-weighted annual effective dose was determined to be 0.32 mSv, which is smaller than the UNSCEAR’s evaluation by 16%, with a range from 0.23 to 0.70 mSv covering 99% of the world population. These values were noted to vary with the solar modulation condition within a range of approximately 15%. All assessed population-weighted annual effective doses as well as their statistical information for each nation are provided in the supplementary files annexed to this report. These data improve our understanding of cosmic-ray radiation exposures to populations globally. PMID:27650664

The impact of ergonomic work environment exposures on the risk of disability pension: Prospective results from DWECS/DREAM.

PubMed

Labriola, Merete; Feveile, Helene; Christensen, Karl B; Strøyer, Jesper; Lund, Thomas

2009-11-01

The objectives were to identify the impact of ergonomic work environment exposures on the risk of disability pension. A representative sample of 8475 employees of the total working population in Denmark were interviewed regarding work environment exposures and followed in a national register with data on granted disability pension. For women, approximately 34% of the disability pension cases were attributable to ergonomic work environment exposures. For men, 21% of the disability pension cases were attributable to ergonomic work environment. Ergonomic work environment, especially physically demanding work, working with hands lifted and repetitive work, are areas of intervention at the workplace that can facilitate and prolong labour market participation. The study provides estimates for the association between ergonomic exposures at work and administrative, cost-related measures of work disability in a large population-based longitudinal cohort study over 14 years. Approximately 21% for men and 34% for women of the disability pension cases were attributable to ergonomic work environment exposures.

Glucose Homeostasis During Short-term and Prolonged Exposure to High Altitudes

PubMed Central

Ader, Marilyn; Bergman, Richard N.

2015-01-01

Most of the literature related to high altitude medicine is devoted to the short-term effects of high-altitude exposure on human physiology. However, long-term effects of living at high altitudes may be more important in relation to human disease because more than 400 million people worldwide reside above 1500 m. Interestingly, individuals living at higher altitudes have a lower fasting glycemia and better glucose tolerance compared with those who live near sea level. There is also emerging evidence of the lower prevalence of both obesity and diabetes at higher altitudes. The mechanisms underlying improved glucose control at higher altitudes remain unclear. In this review, we present the most current evidence about glucose homeostasis in residents living above 1500 m and discuss possible mechanisms that could explain the lower fasting glycemia and lower prevalence of obesity and diabetes in this population. Understanding the mechanisms that regulate and maintain the lower fasting glycemia in individuals who live at higher altitudes could lead to new therapeutics for impaired glucose homeostasis. PMID:25675133

Predicting the sensitivity of populations from individual exposure to chemicals: the role of ecological interactions.

PubMed

Gabsi, Faten; Schäffer, Andreas; Preuss, Thomas G

2014-07-01

Population responses to chemical stress exposure are influenced by nonchemical, environmental processes such as species interactions. A realistic quantification of chemical toxicity to populations calls for the use of methodologies that integrate these multiple stress effects. The authors used an individual-based model for Daphnia magna as a virtual laboratory to determine the influence of ecological interactions on population sensitivity to chemicals with different modes of action on individuals. In the model, hypothetical chemical toxicity targeted different vital individual-level processes: reproduction, survival, feeding rate, or somatic growth rate. As for species interactions, predatory and competition effects on daphnid populations were implemented following a worst-case approach. The population abundance was simulated at different food levels and exposure scenarios, assuming exposure to chemical stress solely or in combination with either competition or predation. The chemical always targeted one vital endpoint. Equal toxicity-inhibition levels differently affected the population abundance with and without species interactions. In addition, population responses to chemicals were highly sensitive to the environmental stressor (predator or competitor) and to the food level. Results show that population resilience cannot be attributed to chemical stress only. Accounting for the relevant ecological interactions would reduce uncertainties when extrapolating effects of chemicals from individuals to the population level. Validated population models should be used for a more realistic risk assessment of chemicals. © 2014 SETAC.

Assessment of Population and Microenvironmental Exposure to Fine Particulate Matter (PM2.5)

NASA Astrophysics Data System (ADS)

Jiao, Wan

A positive relationship exists between fine particulate matter (PM 2.5) exposure and adverse health effects. PM2.5 concentration-response functions used in the quantitative risk assessment were based on findings from human epidemiological studies that relied on areawide ambient concentrations as surrogate for actual ambient exposure, which cannot capture the spatial and temporal variability in human exposures. The goal of the study is to assess inter-individual, geographic and seasonal variability in population exposures to inform the interpretation of available epidemiological studies, and to improve the understanding of how exposure-related factors in important exposure microenvironments contribute to the variability in individual PM2.5 exposure. Typically, the largest percentage of time in which an individual is exposed to PM2.5 of ambient origin occurs in indoor residence, and the highest ambient PM2.5 concentrations occur in transportation microenvironments because of the proximity to on-road traffic emissions. Therefore, indoor residence and traffic-related transportation microenvironments were selected for further assessment in the study. Population distributions of individual daily PM2.5 exposures were estimated for the selected regions and seasons using the Stochastic Human Exposure and Dose Simulation Model for Particulate Matter (SHEDS-PM). For the indoor residence, the current practice by assuming the entire residence to be one large single zone for calculating the indoor residential PM 2.5 concentration was evaluated by applying an indoor air quality model, RISK, to compare indoor PM2.5 concentrations between single-zone and multi-zone scenarios. For the transportation microenvironments, one field data collection focused on in-vehicle microenvironment and was conducted to quantify the variability in the in-vehicle PM2.5 concentration with respect to the outside vehicle concentration for a wide range of conditions that affect intra-vehicle variability

Nickel on the market: a baseline survey of articles in 'prolonged contact' with skin.

PubMed

Ringborg, Evelina; Lidén, Carola; Julander, Anneli

2016-08-01

In April 2014, the European Chemicals Agency defined the concept of 'prolonged contact with skin' as used in the EU nickel restriction. To establish a baseline of nickel-releasing items on the Swedish market conforming with the EU nickel restriction according to the definition of 'prolonged contact' with the skin. We performed a limited market survey in Stockholm, Sweden. Items with metallic parts that come into contact with the skin, except those explicitly mentioned in the legal text, were chosen. The dimethylglyoxime (DMG) test was used to evaluate nickel release. One hundred and forty-one items belonging to one of three categories - accessories, utensils for needlework, painting and writing (called utensils), and electronic devices - were tested in the study. Forty-four percent of all items were DMG test-positive (releasing nickel), and 9% gave a doubtful DMG test result. The large proportion of nickel-releasing items in the present study shows clearly that broader parts of industry need to take action to prevent nickel allergy. The high proportion of DMG test-positive items indicates that there is still much work to be done to reduce the nickel exposure of the population. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Contribution of inorganic arsenic sources to population exposure risk on a regional scale.

PubMed

Chou, Wei-Chun; Chen, Jein-Wen; Liao, Chung-Min

2016-07-01

Chronic exposure to inorganic arsenic (iAs) in the human population is associated with various internal cancers and other adverse outcomes. The purpose of this study was to estimate a population-scale exposure risk attributable to iAs consumptions by linking a stochastic physiological-based pharmacokinetic (PBPK) model and biomonitoring data of iAs in urine. The urinary As concentrations were obtained from a total of 1,043 subjects living in an industrial area of Taiwan. The results showed that the study subjects had an iAs exposure risk of 27 % (the daily iAs intake for 27 % study subjects exceeded the WHO-recommended value, 2.1 μg iAs day(-1) kg(-1) body weight). Moreover, drinking water and cooked rice contributed to the iAs exposure risk by 10 and 41 %, respectively. The predicted risks in the current study were 4.82, 27.21, 34.69, and 64.17 %, respectively, among the mid-range of Mexico, Taiwan (this study), Korea, and Bangladesh reported in the literature. In conclusion, we developed a population-scale-based risk model that covered the broad range of iAS exposure by integrating stochastic PBPK modeling and reverse dosimetry to generate probabilistic distribution of As intake corresponding to urinary As measured from the cohort study. The model can also be updated as new urinary As information becomes available.

Venetoclax does not prolong the QT interval in patients with hematological malignancies: an exposure-response analysis.

PubMed

Freise, Kevin J; Dunbar, Martin; Jones, Aksana K; Hoffman, David; Enschede, Sari L Heitner; Wong, Shekman; Salem, Ahmed Hamed

2016-10-01

Venetoclax (ABT-199/GDC-0199) is a selective first-in-class B cell lymphoma-2 inhibitor being developed for the treatment of hematological malignancies. The aim of this study was to determine the potential of venetoclax to prolong the corrected QT (QTc) interval and to evaluate the relationship between systemic venetoclax concentration and QTc interval. The study population included 176 male and female patients with relapsed or refractory chronic lymphocytic leukemia/small lymphocytic lymphoma (n = 105) or non-Hodgkin's lymphoma (n = 71) enrolled in a phase 1 safety, pharmacokinetic, and efficacy study. Electrocardiograms were collected in triplicate at time-matched points (2, 4, 6, and 8 h) prior to the first venetoclax administration and after repeated venetoclax administration to achieve steady state conditions. Venetoclax doses ranged from 100 to 1200 mg daily. Plasma venetoclax samples were collected after steady state electrocardiogram measurements. The mean and upper bound of the 2-sided 90 % confidence interval (CI) QTc change from baseline were <5 and <10 ms, respectively, at all time points and doses (<400, 400, and >400 mg). Three subjects had single QTc values >500 ms and/or ΔQTc > 60 ms. The effect of venetoclax concentration on both ΔQTc and QTc was not statistically significant (P > 0.05). At the mean maximum concentrations achieved with therapeutic (400 mg) and supra-therapeutic (1200 mg) venetoclax doses, the estimated drug effects on QTc were 0.137 (90 % CI [-1.01 to 1.28]) and 0.263 (90 % CI [-1.92 to 2.45]) ms, respectively. Venetoclax does not prolong QTc interval even at supra-therapeutic doses, and there is no relationship between venetoclax concentrations and QTc interval.

Neural circuits via which single prolonged stress exposure leads to fear extinction retention deficits.

PubMed

Knox, Dayan; Stanfield, Briana R; Staib, Jennifer M; David, Nina P; Keller, Samantha M; DePietro, Thomas

2016-12-01

Single prolonged stress (SPS) has been used to examine mechanisms via which stress exposure leads to post-traumatic stress disorder symptoms. SPS induces fear extinction retention deficits, but neural circuits critical for mediating these deficits are unknown. To address this gap, we examined the effect of SPS on neural activity in brain regions critical for extinction retention (i.e., fear extinction circuit). These were the ventral hippocampus (vHipp), dorsal hippocampus (dHipp), basolateral amygdala (BLA), prelimbic cortex (PL), and infralimbic cortex (IL). SPS or control rats were fear conditioned then subjected to extinction training and testing. Subsets of rats were euthanized after extinction training, extinction testing, or immediate removal from the housing colony (baseline condition) to assay c-Fos levels (measure of neural activity) in respective brain region. SPS induced extinction retention deficits. During extinction training SPS disrupted enhanced IL neural activity and inhibited BLA neural activity. SPS also disrupted inhibited BLA and vHipp neural activity during extinction testing. Statistical analyses suggested that SPS disrupted functional connectivity within the dHipp during extinction training and increased functional connectivity between the BLA and vHipp during extinction testing. Our findings suggest that SPS induces extinction retention deficits by disrupting both excitatory and inhibitory changes in neural activity within the fear extinction circuit and inducing changes in functional connectivity within the Hipp and BLA. © 2016 Knox et al.; Published by Cold Spring Harbor Laboratory Press.

Effect of leucine supplementation on fat free mass with prolonged hypoxic exposure during a 13-day trek to Everest Base Camp: a double-blind randomized study.

PubMed

Wing-Gaia, Stacie L; Gershenoff, Dana C; Drummond, Micah J; Askew, E Wayne

2014-03-01

Loss of body weight and fat-free mass (FFM) are commonly noted with prolonged exposure to hypobaric hypoxia. Recent evidence suggests protein supplementation, specifically leucine, may potentially attenuate loss of FFM in subcaloric conditions during normoxia. The purpose of this study was to determine if leucine supplementation would prevent the loss of FFM in subcaloric conditions during prolonged hypoxia. Eighteen physically active male (n = 10) and female (n = 8) trekkers completed a 13-day trek in Nepal to Everest Base Camp with a mean altitude of 4140 m (range 2810-5364 m). In this double-blind study, participants were randomized to ingest either leucine (LEU) (7 g leucine, 93 kcal, 14.5 g whey-based protein) or an isocaloric isonitrogenous control (CON) (0.3 g LEU, 93 kcal, 11.3 g collagen protein) twice daily prior to meals. Body weight, body composition, and circumferences of bicep, thigh, and calf were measured pre- and post-trek. There was a significant time effect for body weight (-2.2% ± 1.7%), FFM (-1.7% ± 1.5%), fat mass (-4.0% ± 6.9%), and circumferences (p < 0.05). However, there was no treatment effect on body weight (CON -2.3 ± 2.0%; LEU -2.2 ± 1.5%), FFM (CON -2.1 ± 1.5%; LEU -1.2 ± 1.6%), fat mass (CON -2.9% ± 5.9%; LEU -5.4% ± 8.1%), or circumferences. Although a significant loss of body weight, FFM, and fat mass was noted in 13 days of high altitude exposure, FFM loss was not attenuated by leucine. Future studies are needed to determine if leucine attenuates loss of FFM with longer duration high altitude exposure.

Pre-treatment Predictors of Dropout from Prolonged Exposure Therapy in Patients with Chronic Posttraumatic Stress Disorder and Comorbid Substance Use Disorders

PubMed Central

Belleau, Emily L.; Chin, Eu Gene; Wanklyn, Sonya G.; Zambrano-Vazquez, Laura; Schumacher, Julie A.; Coffey, Scott F.

2017-01-01

Posttraumatic stress disorder (PTSD) and substance use disorders (SUDs) are commonly co-occurring disorders associated with more adverse consequences than PTSD alone. Prolonged exposure therapy (PE) is one of the most efficacious treatments for PTSD. However, among individuals with PTSD-SUD, 35–62% of individuals drop out of trauma-focused exposure treatments. Thus, it is important to identify predictors of PTSD treatment dropout among substance abusers with PTSD in order to gain information about adapting treatment strategies to enhance retention and outcomes. The current study explored pre-treatment predictors of early termination from PE treatment in a sample of 85 individuals receiving concurrent treatment for PTSD and a SUD in a residential treatment facility as part of a randomized controlled trial. The results indicated that less education and more anxiety sensitivity uniquely predicted PE treatment dropout. Demographic variables, PTSD severity, SUD severity, mental health comorbidities, and emotion regulation difficulties did not predict treatment dropout. These results suggest that adding pre-treatment interventions that address anxiety sensitivity, and promote social adjustment and cognitive flexibility, could possibly improve PE retention rates in clients with high anxiety or low education. PMID:28147254

Aminoglycoside exposure and renal function before lung transplantation in adult cystic fibrosis patients.

PubMed

Novel-Catin, Etienne; Pelletier, Solenne; Reynaud, Quitterie; Nove-Josserand, Raphaele; Durupt, Stephane; Dubourg, Laurence; Durieu, Isabelle; Fouque, Denis

2018-04-18

Patients with cystic fibrosis (CF) are at risk of kidney injury even before undergoing lung transplantation, because of prolonged exposure to aminoglycosides (AGs), chronic dehydration and complications of diabetes mellitus. The usual equations estimating the glomerular filtration rate (GFR), such as Cockcroft-Gault and Modification of Diet in Renal Disease, are not adapted to the CF population due to patients' low body weight and reduced muscle mass. The aim of this study was to precisely measure GFR in adult CF patients and to see whether repeated AG treatment would impair renal function before lung transplantation. Inulin or iohexol clearances were performed in 25 adult CF patients when they entered the lung transplant waiting list. No patient was treated with AGs at the time of GFR measurement. Body mass index (BMI), history of diabetes mellitus and blood pressure were recorded. Exposure to intravenous (IV) AGs within 5 years prior to the GFR measurement was obtained from the patient's medical files. Urine samples were collected to check for albuminuria and proteinuria. The population was predominantly female (67%). The mean age was 32 years, the mean BMI was 19 kg/m2 and 28% had CF-related diabetes. Median exposure to IV AG within 5 years before GFR measurement was 155 days with a mean dosage of 7.7mg/kg/day. The mean measured GFR was 106 mL/min/1.73 m2 and the mean estimated GFR according to the Chronic Kidney Disease Epidemiology Collaboration formula was 124 mL/min/1.73 m2. Despite prolonged exposure to high-dose IV AG, no decline in GFR was observed in these patients.

Lung volumes identify an at-risk group in persons with prolonged secondhand tobacco smoke exposure but without overt airflow obstruction.

PubMed

Arjomandi, Mehrdad; Zeng, Siyang; Geerts, Jeroen; Stiner, Rachel K; Bos, Bruce; van Koeverden, Ian; Keene, Jason; Elicker, Brett; Blanc, Paul D; Gold, Warren M

2018-01-01

Exposure to secondhand smoke (SHS) is associated with occult obstructive lung disease as evident by abnormal airflow indices representing small airway disease despite having preserved spirometry (normal forced expiratory volume in 1 s-to-forced vital capacity ratio, FEV 1 /FVC). The significance of lung volumes that reflect air trapping in the presence of preserved spirometry is unclear. To investigate whether lung volumes representing air trapping could determine susceptibility to respiratory morbidity in people with SHS exposure but without spirometric chronic obstructive pulmonary disease, we examined a cohort of 256 subjects with prolonged occupational SHS exposure and preserved spirometry. We elicited symptom prevalence by structured questionnaires, examined functional capacity (maximum oxygen uptake, VO 2max ) by exercise testing, and estimated associations of those outcomes with air trapping (plethysmography-measured residual volume-to-total lung capacity ratio, RV/TLC), and progressive air trapping with exertion (increase in fraction of tidal breathing that is flow limited on expiration during exercise (per cent of expiratory flow limitation, %EFL)). RV/TLC was within the predicted normal limits, but was highly variable spanning 22%±13% and 16%±8% across the increments of FEV 1 /FVC and FEV 1 , respectively. Respiratory complaints were prevalent (50.4%) with the most common symptom being ≥2 episodes of cough per year (44.5%). Higher RV/TLC was associated with higher OR of reporting respiratory symptoms (n=256; r 2 =0.03; p=0.011) and lower VO 2max (n=179; r 2 =0.47; p=0.013), and %EFL was negatively associated with VO 2max (n=32; r 2 =0.40; p=0.017). In those at risk for obstruction due to SHS exposure but with preserved spirometry, higher RV/TLC identifies a subgroup with increased respiratory symptoms and lower exercise capacity.

Climate-Related Hazards: A Method for Global Assessment of Urban and Rural Population Exposure to Cyclones, Droughts, and Floods

PubMed Central

Christenson, Elizabeth; Elliott, Mark; Banerjee, Ovik; Hamrick, Laura; Bartram, Jamie

2014-01-01

Global climate change (GCC) has led to increased focus on the occurrence of, and preparation for, climate-related extremes and hazards. Population exposure, the relative likelihood that a person in a given location was exposed to a given hazard event(s) in a given period of time, was the outcome for this analysis. Our objectives were to develop a method for estimating the population exposure at the country level to the climate-related hazards cyclone, drought, and flood; develop a method that readily allows the addition of better datasets to an automated model; differentiate population exposure of urban and rural populations; and calculate and present the results of exposure scores and ranking of countries based on the country-wide, urban, and rural population exposures to cyclone, drought, and flood. Gridded global datasets on cyclone, drought and flood occurrence as well as population density were combined and analysis was carried out using ArcGIS. Results presented include global maps of ranked country-level population exposure to cyclone, drought, flood and multiple hazards. Analyses by geography and human development index (HDI) are also included. The results and analyses of this exposure assessment have implications for country-level adaptation. It can also be used to help prioritize aid decisions and allocation of adaptation resources between countries and within a country. This model is designed to allow flexibility in applying cyclone, drought and flood exposure to a range of outcomes and adaptation measures. PMID:24566046

Utilizing Telehealth to Support Treatment of Acute Stress Disorder in a Theater of War: Prolonged Exposure via Clinical Videoconferencing.

PubMed

Pelton, Dan; Wangelin, Bethany; Tuerk, Peter

2015-05-01

Posttraumatic stress disorder (PTSD) and acute stress disorder are prevalent mental health diagnoses associated with the military operations in Iraq and Afghanistan and are especially significant in service members returning from combat. Prolonged exposure (PE) therapy is a highly effective behavioral treatment for these symptoms, and providing this treatment as soon as possible, even in the midst of a soldier's combat deployment, has strong potential benefits. In the current case study, telehealth technology was used to support the delivery of PE therapy to treat a service member diagnosed with acute stress disorder in a war zone. PE was conducted face-to-face on the relatively secure Forward Operating Base for the first half of therapy and via clinical videoconferencing (CV) to the service member's remote combat outpost during the later stages of therapy. The service member exhibited marked improvements in symptoms over 10 sessions. Results are consistent with previous empirical findings and highlight the potential benefits of using telehealth to deliver evidenced-based treatment for traumatic stress disorders in a war zone. This case study provides a preliminary working model for delivering PE in a combat environment using multiple delivery systems. Benefits and clinical utility of CV-delivered exposure therapy are discussed, particularly for providers pending future operational deployments (e.g., including members of the military, independent government agencies, and first responders) and for those treating patients in remote locations.

Identifying the socioeconomic determinants of population exposure to particulate matter (PM2.5) in China using geographically weighted regression modeling.

PubMed

Chen, Jing; Zhou, Chunshan; Wang, Shaojian; Hu, Jincan

2018-06-04

Air pollution contributes significantly to premature death in China. However, only a limited number of studies have identified the potential determinants of population exposure to PM 2.5 from a socioeconomic perspective. This paper analyses the socioeconomic determinants of population exposure at the city level in China. We first estimated population exposure to PM 2.5 by integrating high resolution spatial distribution maps of PM 2.5 concentrations and population density, using data for 2013. Then, geographically weighted regression (GWR) modeling was undertaken to explore the strength and direction of relationships between the selected socioeconomic factors and population exposure. The results indicate that approximately 75% of the population of China lived in an area where PM 2.5 concentrations were over 35 μg/m 3 in 2013. From the GWR models, we found that the percentages for cities that showed a statistically significant relationship (p < 0.05) between population exposure and each of the six factors were: urbanization, 91.92%; industry share, 91.58%; construction level, 88.55%; urban expansion, 73.40%; income disparity, 64.98%; and private vehicles, 27.27%. The R-squared value for the six factors in the multivariable GWR model was 0.88, and all cities demonstrated a statistically significant relationship. More importantly, the association between the six factors and population exposure was found to be spatially heterogeneous at the local geographic level. Consideration of these six drivers of population exposure can help policy makers and epidemiologists to evaluate and reduce population exposure risks. Copyright © 2018 Elsevier Ltd. All rights reserved.

Prolonged fatigue in Ukraine and the United States: Prevalence and risk factors

PubMed Central

Friedberg, Fred; Tintle, Nathan; Clark, Jake; Bromet, Evelyn J.

2015-01-01

Background Prolonged, severe, unalleviated fatigue may be disabling whether it occurs on its own or in conjunction with medical or psychiatric conditions. This paper compares the prevalence and correlates of prolonged fatigue in general population samples in Ukraine versus the U.S. Methods Population surveys were conducted in 2002 in both Ukraine (Ukraine World Mental Health [WMH] Survey) and the U.S. (National Comorbidity Survey-Replication; NCS-R). Both surveys administered the Composite International Diagnostic Interview (CIDI 3.0), which contained modules assessing: neurasthenia (prolonged fatigue); mood, anxiety, and alcohol/drug use disorders; chronic medical conditions; and demographic characteristics. Multivariable logistic regression was used to examine risk factors in each country. Results The lifetime prevalence of prolonged fatigue was higher in Ukraine (5.2%) than the U.S. (3.7%). In both countries, one-fifth of individuals with prolonged fatigue had no medical or DSM-IV psychiatric condition. Also in both settings, fatigue was significantly associated with sociodemographic characteristics (being female, not working, and married before) as well as early onset and adult episodes of mood/anxiety disorder. Fatigue prevalence in Ukraine increased with age, but decreased in the U.S. at age 70. Unique risk factors for fatigue in Ukraine included lower socio-economic status, Ukrainian vs Russian ethnicity, and cardiovascular disease. Unique risk factors in the U.S. were parental depression/anxiety, adult episodes of alcohol/drugs, pain conditions, and other health problems. Conclusions The lifetime prevalence of prolonged fatigue in Ukraine was 40% higher than that found in U.S. data. In addition, fatigue prevalence increased sharply with age in Ukraine perhaps due to limited social and medical resources and greater comorbidity. PMID:26807341

Spatial aspects of building and population exposure data and their implications for global earthquake exposure modeling

USGS Publications Warehouse

Dell’Acqua, F.; Gamba, P.; Jaiswal, K.

2012-01-01

This paper discusses spatial aspects of the global exposure dataset and mapping needs for earthquake risk assessment. We discuss this in the context of development of a Global Exposure Database for the Global Earthquake Model (GED4GEM), which requires compilation of a multi-scale inventory of assets at risk, for example, buildings, populations, and economic exposure. After defining the relevant spatial and geographic scales of interest, different procedures are proposed to disaggregate coarse-resolution data, to map them, and if necessary to infer missing data by using proxies. We discuss the advantages and limitations of these methodologies and detail the potentials of utilizing remote-sensing data. The latter is used especially to homogenize an existing coarser dataset and, where possible, replace it with detailed information extracted from remote sensing using the built-up indicators for different environments. Present research shows that the spatial aspects of earthquake risk computation are tightly connected with the availability of datasets of the resolution necessary for producing sufficiently detailed exposure. The global exposure database designed by the GED4GEM project is able to manage datasets and queries of multiple spatial scales.

Application of a dynamic population-based model for evaluation of exposure reduction strategies in the baking industry

NASA Astrophysics Data System (ADS)

Meijster, Tim; Warren, Nick; Heederik, Dick; Tielemans, Erik

2009-02-01

Recently a dynamic population model was developed that simulates a population of bakery workers longitudinally through time and tracks the development of work-related sensitisation and respiratory symptoms in each worker. Input for this model comes from cross-sectional and longitudinal epidemiological studies which allowed estimation of exposure response relationships and disease transition probabilities This model allows us to study the development of diseases and transitions between disease states over time in relation to determinants of disease including flour dust and/or allergen exposure. Furthermore it enables more realistic modelling of the health impact of different intervention strategies at the workplace (e.g. changes in exposure may take several years to impact on ill-health and often occur as a gradual trend). A large dataset of individual full-shift exposure measurements and real-time exposure measurements were used to obtain detailed insight into the effectiveness of control measures and other determinants of exposure. Given this information a population wide reduction of the median exposure with 50% was evaluated in this paper.

What would you choose? Sertraline or prolonged exposure in community and PTSD treatment seeking women.

PubMed

Feeny, Norah C; Zoellner, Lori A; Mavissakalian, Matig R; Roy-Byrne, Peter P

2009-01-01

Both sertraline (SER) and prolonged exposure (PE) are empirically supported treatments for chronic posttraumatic stress disorder (PTSD). While efficacious, these treatments are quite different in approach, and such differences may influence both treatment choice and treatment outcome. To date, we know very little about the relative efficacy of pharmacological and psychological treatments for chronic PTSD. In Study 1, we compared rates of treatment choice (SER or PE) in 74 trauma-exposed women. In Study 2, we extended this work to an open-choice treatment trial, in which 31 female assault survivors with chronic PTSD received their choice of SER or PE for ten weeks and were followed over time. In Study 1 (82%) and Study 2 (74.2%), the majority of women chose PE. In Study 2, both SER and PE evidenced moderate to large unadjusted effect sizes, with evidence of an advantage for PE in propensity adjusted analyses at posttreatment. Women with co-occurring major depressive disorder (MDD) were more likely to choose SER than those without MDD. However, among those with MDD, the advantage of PE was particularly evident. Our results highlight the presence of clear treatment preferences for PTSD and their potential impact on outcome. This study underscores the importance of systematic study of patient preferences and encourages a rethinking of one-size fits all approaches to treatment for mental disorders. (c) 2009 Wiley-Liss, Inc.

Implementation outcomes of military provider training in cognitive processing therapy and prolonged exposure therapy for post-traumatic stress disorder.

PubMed

Borah, Elisa V; Wright, Edward C; Donahue, D Allen; Cedillos, Elizabeth M; Riggs, David S; Isler, William C; Peterson, Alan L

2013-09-01

Between 2006 and 2012, the Department of Defense trained thousands of military mental health providers in the use of evidence-based treatments for post-traumatic stress disorder. Most providers were trained in multiday workshops that focused on the use of Cognitive Processing Therapy and Prolonged Exposure. This study is a follow-up evaluation of the implementation practices of 103 Air Force mental health providers. A survey was administered online to workshop participants; 34.2% of participants responded. Findings on treatment implementation with the providers indicated that a majority of respondents found the trainings valuable and were interested in using the treatments, yet they reported a lack of time in their clinic appointment structure to support their use. Insufficient supervision was also cited as a barrier to treatment use. Results suggest the need to improve strategies for implementing evidence-based practices with providers to enhance clinical outcomes in military settings. Reprint & Copyright © 2013 Association of Military Surgeons of the U.S.

Variations in population exposure and sensitivity to lahar hazards from Mount Rainier, Washington

NASA Astrophysics Data System (ADS)

Wood, Nathan; Soulard, Christopher

2009-12-01

Although much has been done to understand, quantify, and delineate volcanic hazards, there are fewer efforts to assess societal vulnerability to these hazards, particularly demographic differences in exposed populations or spatial variations in exposure to regional hazards. To better understand population diversity in volcanic hazard zones, we assess the number and types of people in a single type of hazard zone (lahars) for 27 communities downstream of Mount Rainier, Washington (USA). Using various socioeconomic and hazard datasets, we estimate that there are more than 78 000 residents, 59 000 employees, several dependent-population facilities (e.g., child-day-care centers, nursing homes) and numerous public venues (e.g., churches, hotels, museums) in a Mount Rainier lahar-hazard zone. We find that communities vary in the primary category of individuals in lahar-prone areas—exposed populations are dominated by residents in some communities (e.g., Auburn), employees in others (e.g., Tacoma), and tourists likely outnumber both of these groups in yet other areas (e.g., unincorporated Lewis County). Population exposure to potential lahar inundation varies considerably—some communities (e.g., Auburn) have large numbers of people but low percentages of them in hazard zones, whereas others (e.g., Orting) have fewer people but they comprise the majority of a community. A composite lahar-exposure index is developed to help emergency managers understand spatial variations in community exposure to lahars and results suggest that Puyallup has the highest combination of high numbers and percentages of people and assets in lahar-prone areas. Risk education and preparedness needs will vary based on who is threatened by future lahars, such as residents, employees, tourists at a public venue, or special-needs populations at a dependent-care facility. Emergency managers must first understand the people whom they are trying to prepare before they can expect these people to take

Variations in population exposure and sensitivity to lahar hazards from Mount Rainier, Washington

USGS Publications Warehouse

Wood, N.; Soulard, C.

2009-01-01

Although much has been done to understand, quantify, and delineate volcanic hazards, there are fewer efforts to assess societal vulnerability to these hazards, particularly demographic differences in exposed populations or spatial variations in exposure to regional hazards. To better understand population diversity in volcanic hazard zones, we assess the number and types of people in a single type of hazard zone (lahars) for 27 communities downstream of Mount Rainier, Washington (USA). Using various socioeconomic and hazard datasets, we estimate that there are more than 78 000 residents, 59 000 employees, several dependent-population facilities (e.g., child-day-care centers, nursing homes) and numerous public venues (e.g., churches, hotels, museums) in a Mount Rainier lahar-hazard zone. We find that communities vary in the primary category of individuals in lahar-prone areas-exposed populations are dominated by residents in some communities (e.g., Auburn), employees in others (e.g., Tacoma), and tourists likely outnumber both of these groups in yet other areas (e.g., unincorporated Lewis County). Population exposure to potential lahar inundation varies considerably-some communities (e.g., Auburn) have large numbers of people but low percentages of them in hazard zones, whereas others (e.g., Orting) have fewer people but they comprise the majority of a community. A composite lahar-exposure index is developed to help emergency managers understand spatial variations in community exposure to lahars and results suggest that Puyallup has the highest combination of high numbers and percentages of people and assets in lahar-prone areas. Risk education and preparedness needs will vary based on who is threatened by future lahars, such as residents, employees, tourists at a public venue, or special-needs populations at a dependent-care facility. Emergency managers must first understand the people whom they are trying to prepare before they can expect these people to take

QT Prolongation, Torsades de Pointes, and Psychotropic Medications: A 5-Year Update.

PubMed

Beach, Scott R; Celano, Christopher M; Sugrue, Alan M; Adams, Caitlin; Ackerman, Michael J; Noseworthy, Peter A; Huffman, Jeff C

Some psychotropic medications have been associated with prolongation of the QT interval and QT prolongation, especially in those with medical illness, and are linked to lethal ventricular arrhythmias, such as Torsades de Pointes (TdP). In 2013, we published a review of QT prolongation, TdP, and psychotropic medications. We provide an update over the past 5 years on the specific concerns most relevant to clinicians who see medically ill patients. In this nonsystematic review, we aimed to carefully and intensively identify new articles by utilizing a structured PubMed search from 2012-present. QT prolongation remains an imperfect, though well-established marker of risk for TdP. Among antidepressant medications, citalopram does appear to prolong the QT interval more than other selective serotonin reuptake inhibitors, though the clinical significance of this prolongation remains unclear. Escitalopram appears to prolong the QT interval to a lesser extent. Haloperidol carries a risk for QT prolongation, but the assertion that intravenous haloperidol is inherently riskier may be confounded by its primary use in medically ill populations. Among atypical antipsychotic agents, ziprasidone-and possibly iloperidone-is associated with the greatest QT prolongation, whereas aripiprazole appears safest from this standpoint. The evidence for clinically meaningful QT prolongation with most classes of psychiatric agents remains minimal. The most important risk-reducing intervention clinicians can make is undertaking a careful analysis of other QT risk factors when prescribing psychiatric medications. Copyright © 2017 Academy of Consultation-Liaison Psychiatry. Published by Elsevier Inc. All rights reserved.

Opposite Influence of Perceptual Memory on Initial and Prolonged Perception of Sensory Ambiguity

PubMed Central

de Jong, Maartje Cathelijne; Knapen, Tomas; van Ee, Raymond

2012-01-01

Observers continually make unconscious inferences about the state of the world based on ambiguous sensory information. This process of perceptual decision-making may be optimized by learning from experience. We investigated the influence of previous perceptual experience on the interpretation of ambiguous visual information. Observers were pre-exposed to a perceptually stabilized sequence of an ambiguous structure-from-motion stimulus by means of intermittent presentation. At the subsequent re-appearance of the same ambiguous stimulus perception was initially biased toward the previously stabilized perceptual interpretation. However, prolonged viewing revealed a bias toward the alternative perceptual interpretation. The prevalence of the alternative percept during ongoing viewing was largely due to increased durations of this percept, as there was no reliable decrease in the durations of the pre-exposed percept. Moreover, the duration of the alternative percept was modulated by the specific characteristics of the pre-exposure, whereas the durations of the pre-exposed percept were not. The increase in duration of the alternative percept was larger when the pre-exposure had lasted longer and was larger after ambiguous pre-exposure than after unambiguous pre-exposure. Using a binocular rivalry stimulus we found analogous perceptual biases, while pre-exposure did not affect eye-bias. We conclude that previously perceived interpretations dominate at the onset of ambiguous sensory information, whereas alternative interpretations dominate prolonged viewing. Thus, at first instance ambiguous information seems to be judged using familiar percepts, while re-evaluation later on allows for alternative interpretations. PMID:22295095

Disaggregation of nation-wide dynamic population exposure estimates in The Netherlands: Applications of activity-based transport models

NASA Astrophysics Data System (ADS)

Beckx, Carolien; Int Panis, Luc; Uljee, Inge; Arentze, Theo; Janssens, Davy; Wets, Geert

Traditional exposure studies that link concentrations with population data do not always take into account the temporal and spatial variations in both concentrations and population density. In this paper we present an integrated model chain for the determination of nation-wide exposure estimates that incorporates temporally and spatially resolved information about people's location and activities (obtained from an activity-based transport model) and about ambient pollutant concentrations (obtained from a dispersion model). To the best of our knowledge, it is the first time that such an integrated exercise was successfully carried out in a fully operational modus for all models under consideration. The evaluation of population level exposure in The Netherlands to NO 2 at different time-periods, locations, for different subpopulations (gender, socio-economic status) and during different activities (residential, work, transport, shopping) is chosen as a case-study to point out the new features of this methodology. Results demonstrate that, by neglecting people's travel behaviour, total average exposure to NO 2 will be underestimated by 4% and hourly exposure results can be underestimated by more than 30%. A more detailed exposure analysis reveals the intra-day variations in exposure estimates and the presence of large exposure differences between different activities (traffic > work > shopping > home) and between subpopulations (men > women, low socio-economic class > high socio-economic class). This kind of exposure analysis, disaggregated by activities or by subpopulations, per time of day, provides useful insight and information for scientific and policy purposes. It demonstrates that policy measures, aimed at reducing the overall (average) exposure concentration of the population may impact in a different way depending on the time of day or the subgroup considered. From a scientific point of view, this new approach can be used to reduce exposure misclassification.

Pharmacokinetics of prolonged-release tacrolimus and implications for use in solid organ transplant recipients.

PubMed

Tanzi, Maria G; Undre, Nasrullah; Keirns, James; Fitzsimmons, William E; Brown, Malcolm; First, M Roy

2016-08-01

Prolonged-release tacrolimus was developed as a once-daily formulation with ethylcellulose as the excipient, resulting in slower release and reduction in peak concentration (Cmax ) for a given dose compared with immediate-release tacrolimus, which is administered twice daily. This manuscript reviews pharmacokinetic information on prolonged-release tacrolimus in healthy subjects, in transplant recipients converted from immediate-release tacrolimus, and in de novo kidney and liver transplant recipients. As with the immediate-release formulation, prolonged-release tacrolimus shows a strong correlation between trough concentration (Cmin ) and area under the 24-hour time-concentration curve (AUC24 ), indicating that trough whole blood concentrations provide an accurate measure of drug exposure. We present the pharmacokinetic similarities and differences between the two formulations, so that prescribing physicians will have a better understanding of therapeutic drug monitoring in patients receiving prolonged-release tacrolimus. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Review of exposure therapy: a gold standard for PTSD treatment.

PubMed

Rauch, Sheila A M; Eftekhari, Afsoon; Ruzek, Josef I

2012-01-01

Prolonged exposure (PE) is an effective first-line treatment for posttraumatic stress disorder (PTSD), regardless of the type of trauma, for Veterans and military personnel. Extensive research and clinical practice guidelines from various organizations support this conclusion. PE is effective in reducing PTSD symptoms and has also demonstrated efficacy in reducing comorbid issues such as anger, guilt, negative health perceptions, and depression. PE has demonstrated efficacy in diagnostically complex populations and survivors of single- and multiple-incident traumas. The PE protocol includes four main therapeutic components (i.e., psychoeducation, in vivo exposure, imaginal exposure, and emotional processing). In light of PE's efficacy, the Veterans Health Administration designed and supported a PE training program for mental health professionals that has trained over 1,300 providers. Research examining the mechanisms involved in PE and working to improve its acceptability, efficacy, and efficiency is underway with promising results.

Variable population exposure and distributed travel speeds in least-cost tsunami evacuation modelling

NASA Astrophysics Data System (ADS)

Fraser, S. A.; Wood, N. J.; Johnston, D. M.; Leonard, G. S.; Greening, P. D.; Rossetto, T.

2014-11-01

Evacuation of the population from a tsunami hazard zone is vital to reduce life-loss due to inundation. Geospatial least-cost distance modelling provides one approach to assessing tsunami evacuation potential. Previous models have generally used two static exposure scenarios and fixed travel speeds to represent population movement. Some analyses have assumed immediate departure or a common evacuation departure time for all exposed population. Here, a method is proposed to incorporate time-variable exposure, distributed travel speeds, and uncertain evacuation departure time into an existing anisotropic least-cost path distance framework. The method is demonstrated for hypothetical local-source tsunami evacuation in Napier City, Hawke's Bay, New Zealand. There is significant diurnal variation in pedestrian evacuation potential at the suburb level, although the total number of people unable to evacuate is stable across all scenarios. Whilst some fixed travel speeds approximate a distributed speed approach, others may overestimate evacuation potential. The impact of evacuation departure time is a significant contributor to total evacuation time. This method improves least-cost modelling of evacuation dynamics for evacuation planning, casualty modelling, and development of emergency response training scenarios. However, it requires detailed exposure data, which may preclude its use in many situations.

Variable population exposure and distributed travel speeds in least-cost tsunami evacuation modelling

USGS Publications Warehouse

Fraser, Stuart A.; Wood, Nathan J.; Johnston, David A.; Leonard, Graham S.; Greening, Paul D.; Rossetto, Tiziana

2014-01-01

Evacuation of the population from a tsunami hazard zone is vital to reduce life-loss due to inundation. Geospatial least-cost distance modelling provides one approach to assessing tsunami evacuation potential. Previous models have generally used two static exposure scenarios and fixed travel speeds to represent population movement. Some analyses have assumed immediate departure or a common evacuation departure time for all exposed population. Here, a method is proposed to incorporate time-variable exposure, distributed travel speeds, and uncertain evacuation departure time into an existing anisotropic least-cost path distance framework. The method is demonstrated for hypothetical local-source tsunami evacuation in Napier City, Hawke's Bay, New Zealand. There is significant diurnal variation in pedestrian evacuation potential at the suburb level, although the total number of people unable to evacuate is stable across all scenarios. Whilst some fixed travel speeds approximate a distributed speed approach, others may overestimate evacuation potential. The impact of evacuation departure time is a significant contributor to total evacuation time. This method improves least-cost modelling of evacuation dynamics for evacuation planning, casualty modelling, and development of emergency response training scenarios. However, it requires detailed exposure data, which may preclude its use in many situations.

Applicability of western chemical dietary exposure models to the Chinese population.

PubMed

Zhao, Shizhen; Price, Oliver; Liu, Zhengtao; Jones, Kevin C; Sweetman, Andrew J

2015-07-01

A range of exposure models, which have been developed in Europe and North America, are playing an increasingly important role in priority setting and the risk assessment of chemicals. However, the applicability of these tools, which are based on Western dietary exposure pathways, to estimate chemical exposure to the Chinese population to support the development of a risk-based environment and exposure assessment, is unclear. Three frequently used modelling tools, EUSES, RAIDAR and ACC-HUMANsteady, have been evaluated in terms of human dietary exposure estimation by application to a range of chemicals with different physicochemical properties under both model default and Chinese dietary scenarios. Hence, the modelling approaches were assessed by considering dietary pattern differences only. The predicted dietary exposure pathways were compared under both scenarios using a range of hypothetical and current emerging contaminants. Although the differences across models are greater than those between dietary scenarios, model predictions indicated that dietary preference can have a significant impact on human exposure, with the relatively high consumption of vegetables and cereals resulting in higher exposure via plants-based foodstuffs under Chinese consumption patterns compared to Western diets. The selected models demonstrated a good ability to identify key dietary exposure pathways which can be used for screening purposes and an evaluative risk assessment. However, some model adaptations will be required to cover a number of important Chinese exposure pathways, such as freshwater farmed-fish, grains and pork. Copyright © 2015 Elsevier Inc. All rights reserved.

Physiologic effects of prolonged conducted electrical weapon discharge in ethanol-intoxicated adults.

PubMed

Moscati, Ronald; Ho, Jeffrey D; Dawes, Donald M; Miner, James R

2010-06-01

This study examines the physiologic effects of prolonged conducted electrical weapon (CEW) exposure on alcohol-intoxicated adult subjects. Adult volunteers were recruited at a TASER International training conference. All subjects ingested mixed drinks until clinical intoxication or until a minimum breath alcohol level of 0.08 mg/dL was achieved. Blood samples for venous pH, Pco(2), bicarbonate, and lactate were measured in all subjects at baseline, immediately after alcohol ingestion, immediately after exposure to a 15-second TASER X26 discharge (Taser International Inc, Scottsdale, AZ), and 24 hours post-alcohol ingestion. Laboratory values were compared at sampling times using repeated-measure analysis of variance. A focused analysis comparing time points within groups was then performed using paired t tests. Twenty-two subjects were enrolled into the study. There was a decrease in pH and bicarbonate and an increase in lactate after alcohol ingestion. There was a further increase in lactate and drop in pH after CEW exposure. No subject experienced a significant adverse event. All values had returned to baseline levels at 24 hours except lactate, which demonstrated a small but clinically insignificant increase. Prolonged continuous CEW exposure in the setting of acute alcohol intoxication has no clinically significant effect on subjects in terms of markers of metabolic acidosis. The acidosis seen is consistent with what occurs with ethanol intoxication or moderate exertion. Copyright (c) 2010 Elsevier Inc. All rights reserved.

Sun Exposure Prevalence and Associated Skin Health Habits: Results from the Austrian Population-Based UVSkinRisk Survey

PubMed Central

Haluza, Daniela; Simic, Stana; Moshammer, Hanns

2016-01-01

Recreational sun exposure accounts for a large number of acute and chronic dermatological diseases, including skin cancer. This study aimed at estimating the one-year prevalence of sun exposure and skin health-associated knowledge and attitudes among Austrian citizens. The population-based UVSkinRisk survey investigated a representative sample of Austrian adults using a structured questionnaire. In total, 1500 study subjects (median age 33.0 years, 50.5% females) participated in this questionnaire survey. Among study participants, prevalence of sun exposure was 47%, with slightly higher rates in males (48%) compared to females (46%). Younger age, lower professional category, darker skin type, motives to tan, sunbed use, sunburn, and outdoor sport activity increased the odds for prevalent sun exposure. This is the first population-based study evaluating the prevailing sun exposure and recreational habits influencing skin health among Austrian citizens. Despite public media campaigns educating on the harmful effects of sunlight exposure, we found a high prevalence of self-reported sunlight exposure. The results suggest that multifaceted socio-cultural characteristics stimulate recreational sun exposure and tanning habits. Communicating individualized Public (Skin) Health messages might be the key to prevent photo-induced skin health hazards in light-skinned populations. The practical and theoretical implications of these findings are discussed. PMID:26797627

Exposures Related to House Dust Microbiota in a U.S. Farming Population.

PubMed

Lee, Mi Kyeong; Carnes, Megan U; Butz, Natasha; Azcarate-Peril, M Andrea; Richards, Marie; Umbach, David M; Thorne, Peter S; Beane Freeman, Laura E; Peddada, Shyamal D; London, Stephanie J

2018-06-01

Environmental factors can influence the house dust microbiota, which may impact health outcomes. Little is known about how farming exposures impact the indoor microbiota. We aimed to identify exposures related to bacterial communities in house dust in a U.S. farming population. We used 16S rRNA amplicon sequencing to characterize bacterial communities in vacuumed dust samples from the bedrooms of a subset of 879 households of farmers and farmers' spouses enrolled in the Agricultural Lung Health Study (ALHS), a case-control study of asthma nested within the Agricultural Health Study (AHS) in North Carolina and Iowa. Information on current farming (past 12 mo), including both crop and animal farming, and other potential microbial sources was obtained via questionnaires. We used linear regression to evaluate associations between exposures and bacterial diversity within each sample, analysis of similarity (ANOSIM), and permutational multivariate analysis of variance (PERMANOVA) to identify exposures related to diversity between samples, and analysis of composition of microbiome to examine whether exposures related to diversity were also related to differential abundance of specific operational taxonomic units (OTUs). Current farming was positively associated with bacterial diversity in house dust, with or without adjustment for nonfarm exposures related to diversity, including presence of indoor pets, home condition, and season of dust collection. Many taxa exhibited differential abundance related to farming. Some taxa in the phyla Chloroflexi and Verrucomicrobia were associated [false discovery rate (FDR)<0.05] with farming but not with other nonfarm factors. Many taxa correlated with the concentration of house dust of endotoxin, commonly studied as a general marker of exposure to the farming environment. In this farming population, house dust microbiota differed by current farming status. Understanding the determinants of the indoor microbiota is the first step

Vestibulo-Cervico-Ocular Responses and Tracking Eye Movements after Prolonged Exposure to Microgravity

NASA Technical Reports Server (NTRS)

Kornilova, L. N.; Naumov, I. A.; Azarov, K. A.; Sagalovitch, S. V.; Reschke, Millard F.; Kozlovskaya, I. B.

2007-01-01

The vestibular function and tracking eye movements were investigated in 12 Russian crew members of ISS missions on days 1(2), 4(5-6), and 8(9-10) after prolonged exposure to microgravity (126 to 195 days). The spontaneous oculomotor activity, static torsional otolith-cervico-ocular reflex, dynamic vestibulo-cervico-ocular responses, vestibular reactivity, tracking eye movements, and gaze-holding were studied using videooculography (VOG) and electrooculography (EOG) for parallel eye movement recording. On post-flight days 1-2 (R+1-2) some cosmonauts demonstrated: - an increased spontaneous oculomotor activity (floating eye movements, spontaneous nystagmus of the typical and atypical form, square wave jerks, gaze nystagmus) with the head held in the vertical position; - suppressed otolith function (absent or reduced by one half amplitude of torsional compensatory eye counter-rolling) with the head inclined statically right- or leftward by 300; - increased vestibular reactivity (lowered threshold and increased intensity of the vestibular nystagmus) during head turns around the longitudinal body axis at 0.125 Hz; - a significant change in the accuracy, velocity, and temporal characteristics of the eye tracking. The pattern, depth, dynamics, and velocity of the vestibular function and tracking eye movements recovery varied with individual participants in the investigation. However, there were also regular responses during readaptation to the normal gravity: - suppression of the otolith function was typically accompanied by an exaggerated vestibular reactivity; - the structure of visual tracking (the accuracy of fixational eye rotations, smooth tracking, and gaze-holding) was disturbed (the appearance of correcting saccades, the transition of smooth tracking to saccadic tracking) only in those cosmonauts who, in parallel to an increased reactivity of the vestibular input, also had central changes in the oculomotor system (spontaneous nystagmus, gaze nystagmus).

Transgenerational effects and recovery of microplastics exposure in model populations of the freshwater cladoceran Daphnia magna Straus.

PubMed

Martins, Alexandra; Guilhermino, Lúcia

2018-08-01

The environmental contamination by microplastics is a global challenge to ecosystem and human health, and the knowledge on the long-term effects of such particles is limited. Thus, the effects of microplastics and post-exposure recovery were investigated over 4 generations (F 0 , F 1 , F 2 , F 3 ) using Daphnia magna as model. Effect criteria were parental mortality, growth, several reproductive parameters, and population growth rate. Microplastics exposure (0.1mg/l of pristine polymer microspheres 1-5μm diameter) caused parental mortality (10-100%), and significantly (p≤0.05) decreased growth, reproduction, and population growth rate leading to the extinction of the microplastics-exposed model population in the F 1 generation. Females descending from those exposed to microplastics in F 0 and exposed to clean medium presented some recovery but up to the F 3 generation they still had significantly (p≤0.05) reduced growth, reproduction, and population growth rate. Overall, these results indicate that D. magna recovery from chronic exposure to microplastics may take several generations, and that the continuous exposure over generations to microplastics may cause population extinction. These findings have implications to aquatic ecosystem functioning and services, and raise concern on the long-term animal and human exposure to microplastics through diverse routes. Copyright © 2018. Published by Elsevier B.V.

Matgéné: a program to develop job-exposure matrices in the general population in France.

PubMed

Févotte, Joëlle; Dananché, Brigitte; Delabre, Laurène; Ducamp, Stephane; Garras, Loïc; Houot, Marie; Luce, Danièle; Orlowski, Ewa; Pilorget, Corinne; Lacourt, Aude; Brochard, Patrick; Goldberg, Marcel; Imbernon, Ellen

2011-10-01

Matgéné is a program to develop job-exposure matrices (JEMs) adapted to the general population in France for the period since 1950. The aim is to create retrospective exposure assessment tools for estimating the prevalence of occupational exposure to various agents that can then be correlated to health-related parameters. JEMs were drawn up by a team of six industrial hygienists who based their assessments on available occupational measurement, economic and statistical data, and several thousand job descriptions from epidemiological studies performed in France since 1984. Each JEM is specific to one agent, assessing exposure for a set of homogeneous combinations (occupation × activity × period) according to two occupational classifications (ISCO 1968 and PCS 1994) and one economic activities classification (NAF 2000). The cells of the JEM carry an estimate of the probability and level of exposure. Level is estimated by the duration and intensity of exposure-linked tasks or by description of the tasks when exposure measurement data are lacking for the agent in question. The JEMs were applied to a representative sample of the French population in 2007, and prevalence for each exposure was estimated in various population groups. All documents and data are available on a dedicated website. By the end of 2010, 18 JEMs have been developed and eight are under development, concerning a variety of chemical agents: organic and mineral dust, mineral fibers, and solvents. By implementation in the French population, exposure prevalences were calculated at different dates and for complete careers, and attributable risk fractions were estimated for certain pathologies. Some of these results were validated by comparison with those of other programs. Initial Matgéné JEMs results are in agreement with the French and international literature, thus validating the methodology. Exposure estimates precision, however, vary between agents and according to the amount of exposure

Prolonged exposure to 1,25(OH)2D3 and high ionized calcium induces FGF-23 production in intestinal epithelium-like Caco-2 monolayer: A local negative feedback for preventing excessive calcium transport.

PubMed

Rodrat, Mayuree; Wongdee, Kannikar; Panupinthu, Nattapon; Thongbunchoo, Jirawan; Teerapornpuntakit, Jarinthorn; Krishnamra, Nateetip; Charoenphandhu, Narattaphol

2018-02-15

Overdose of oral calcium supplement and excessive intestinal calcium absorption can contribute pathophysiological conditions, e.g., nephrolithiasis, vascular calcification, dementia, and cardiovascular accident. Since our previous investigation has indicated that fibroblast growth factor (FGF)-23 could abolish the 1,25-dihydroxyvitamin D 3 [1,25(OH) 2 D 3 ]-enhanced calcium absorption, we further hypothesized that FGF-23 produced locally in the enterocytes might be part of a local negative feedback loop to regulate calcium absorption. Herein, 1,25(OH) 2 D 3 was found to enhance the transcellular calcium transport across the epithelium-like Caco-2 monolayer, and this stimulatory effect was diminished by preceding prolonged exposure to high-dose 1,25(OH) 2 D 3 or high concentration of apical ionized calcium. Pretreatment with a neutralizing antibody for FGF-23 prevented this negative feedback regulation of calcium hyperabsorption induced by 1,25(OH) 2 D 3 . FGF-23 exposure completely abolished the 1,25(OH) 2 D 3 -enhanced calcium transport. Western blot analysis revealed that FGF-23 expression was upregulated in a dose-dependent manner by 1,25(OH) 2 D 3 or apical calcium exposure. Finally, calcium-sensing receptor (CaSR) inhibitors were found to prevent the apical calcium-induced suppression of calcium transport. In conclusion, prolonged exposure to high apical calcium and calcium hyperabsorption were sensed by CaSR, which, in turn, increased FGF-23 expression to suppress calcium transport. This local negative feedback loop can help prevent unnecessary calcium uptake and its detrimental consequences. Copyright © 2018 Elsevier Inc. All rights reserved.

Exposure to pesticides and mental disorders in a rural population of Southern Brazil.

PubMed

Campos, Ÿlida; Dos Santos Pinto da Silva, Valéria; Sarpa Campos de Mello, Márcia; Barros Otero, Ubirani

2016-09-01

Exposure to pesticides has been associated with mental disorders, especially in occupationally exposed populations, such as farmers. This effect has been attributed to the neurotoxic and endocrine-disrupting activity of pesticides, as suggested by experimental studies. To determine the prevalence of common mental disorders and self-reported depression, and analyze their association with the exposure to pesticides in a rural population resident in the municipality of Dom Feliciano, Rio Grande do Sul, where tobacco farming is the main economic activity. A cross-sectional study evaluating the prevalence of common mental disorders and self-reported depression in a sample of 869 adult individuals resident in Dom Feliciano, between October 2011 and March 2012 was performed. The evaluation of common mental disorders was performed using the Self-Reporting Questionnaire (SRQ-20), setting a cutoff point of 8 for both genders. A standardized questionnaire was used to obtain information on self-reported depression upon prior diagnosis by a health professional, and self-reported exposure to pesticide. In order to evaluate the association between exposure to pesticides and mental disorders, a non-conditional multivariate logistic regression analysis was performed. The prevalence of common mental disorders and self-reported depression in the sample population were 23% and 21%, respectively. Among individuals who reported depression, an increase of 73% was observed in the odds of pesticide exposure at an age equal to or less than 15 years. There was a positive association between self-reported pesticide poisoning and common mental disorders (OR=2.63; 95% CI, 1.62-4.25) as well as self-reported depression (OR=2.62; 95% CI, 1.63-4.21). Individuals who reported depression had a greater odds of exposure to pyrethroids (OR=1.80; 95% CI, 1.01-3.21) and aliphatic alcohol (OR=1.99; 95% CI, 1.04-3.83). An SRQ-20≥8 was associated with an approximately seven times higher odds of exposure

Augmenting Prolonged Exposure therapy for PTSD with intranasal oxytocin: A randomized, placebo-controlled pilot trial.

PubMed

Flanagan, Julianne C; Sippel, Lauren M; Wahlquist, Amy; Moran-Santa Maria, Megan M; Back, Sudie E

2018-03-01

Posttraumatic stress disorder (PTSD) is a chronic, debilitating condition for which Prolonged Exposure (PE) therapy is highly efficacious. However, for some individuals, premature dropout and residual PTSD symptoms remain obstacles. The neuropeptide oxytocin is a promising candidate to enhance PE due to its ability to enhance 1) prosocial cognition and behavior, which are theorized to promote positive working alliance, and 2) extinction learning, which is the central mechanism of action underlying successful PE treatment. Despite a robust theoretical rationale, no studies to date have combined evidence-based psychotherapy for PTSD with oxytocin. This randomized, placebo-controlled, double-blind pilot trial examined the feasibility, safety, and preliminary efficacy of augmenting PE with oxytocin. Participants were 17 individuals with diverse index traumas. Participants self-administered intranasal oxytocin (40 IU) or matching placebo 45 min prior to each weekly PE therapy session. One adverse event occurred in the placebo group and three individuals dropped out (17.6%; 2 oxytocin group and 1 placebo group). The oxytocin group demonstrated lower PTSD and depression symptoms during PE, and had higher working alliance scores, although these differences did not reach statistical significance. Although preliminary, the findings support the feasibility of oxytocin combined with PE. Adequately powered studies are necessary to determine whether oxytocin enhances PE treatment outcomes and to examine potential mechanisms, such as accelerating extinction learning, enhancing early response, and preventing premature dropout. NCT03238924. Copyright © 2017. Published by Elsevier Ltd.

Prenatal nicotinic exposure upregulates pulmonary C-fiber NK1R expression to prolong pulmonary C-fiber-mediated apneic response

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhao, Lei; Zhuang, Jianguo; Zang, Na

Prenatal nicotinic exposure (PNE) prolongs bronchopulmonary C-fiber (PCF)-mediated apneic response to intra-atrial bolus injection of capsaicin in rat pups. The relevant mechanisms remain unclear. Pulmonary substance P and adenosine and their receptors (neurokinin-A receptor, NK1R and ADA{sub 1} receptor, ADA{sub 1}R) and transient receptor potential cation channel subfamily V member 1 (TRPV1) expressed on PCFs are critical for PCF sensitization and/or activation. Here, we compared substance P and adenosine in BALF and NK1R, ADA{sub 1}R, and TRPV1 expression in the nodose/jugular (N/J) ganglia (vagal pulmonary C-neurons retrogradely labeled) between Ctrl and PNE pups. We found that PNE failed to changemore » BALF substance P and adenosine content, but significantly upregulated both mRNA and protein TRPV1 and NK1R in the N/J ganglia and only NK1R mRNA in pulmonary C-neurons. To define the role of NK1R in the PNE-induced PCF sensitization, the apneic response to capsaicin (i.v.) without or with pretreatment of SR140333 (a peripheral and selective NK1R antagonist) was compared and the prolonged apnea by PNE significantly shortened by SR140333. To clarify if the PNE-evoked responses depended on action of nicotinic acetylcholine receptors (nAChRs), particularly α7nAChR, mecamylamine or methyllycaconitine (a general nAChR or a selective α7nAChR antagonist) was administrated via another mini-pump over the PNE period. Mecamylamine or methyllycaconitine eliminated the PNE-evoked mRNA and protein responses. Our data suggest that PNE is able to elevate PCF NK1R expression via activation of nAChRs, especially α7nAChR, which likely contributes to sensitize PCFs and prolong the PCF-mediated apneic response to capsaicin. - Highlights: • PNE upregulated NK1R and TRPV1 gene and protein expression in the N/J ganglia. • PNE only elevated NK1R mRNA in vagal pulmonary C-neurons. • Blockage of peripheral NK1R reduced the PNE-induced PCF sensitization. • PNE induced gene and

Bacterial population dynamics during the ensiling of Medicago sativa (alfalfa) and subsequent exposure to air.

PubMed

McGarvey, J A; Franco, R B; Palumbo, J D; Hnasko, R; Stanker, L; Mitloehner, F M

2013-06-01

To describe, at high resolution, the bacterial population dynamics and chemical transformations during the ensiling of alfalfa and subsequent exposure to air. Samples of alfalfa, ensiled alfalfa and silage exposed to air were collected and their bacterial population structures compared using 16S rRNA gene libraries containing approximately 1900 sequences each. Cultural and chemical analyses were also performed to complement the 16S gene sequence data. Sequence analysis revealed significant differences (P < 0·05) in the bacterial populations at each time point. The alfalfa-derived library contained mostly sequences associated with the Gammaproteobacteria (including the genera: Enterobacter, Erwinia and Pantoea); the ensiled material contained mostly sequences associated with the lactic acid bacteria (LAB) (including the genera: Lactobacillus, Pediococcus and Lactococcus). Exposure to air resulted in even greater percentages of LAB, especially among the genus Lactobacillus, and a significant drop in bacterial diversity. In-depth 16S rRNA gene sequence analysis revealed significant bacterial population structure changes during ensiling and again during exposure to air. This in-depth description of the bacterial population dynamics that occurred during ensiling and simulated feed out expands our knowledge of these processes. © 2013 The Society for Applied Microbiology No claim to US Government works.

INCREASED SUSCEPTIBILITY OF ADULTS FOLLOWING DEVELOPMENT EXPOSURE TO NEUROTOXICANTS: ANOTHER SUSCEPTIBLE POPULATION?

EPA Science Inventory

There is considerable public and regulatory interest in the adverse outcomes of developmental exposure to toxicants. The 1996 Food Quality Protection Act spurred research on understanding potential neurotoxic, immunotoxic, and endocrine outcomes in susceptible populations, parti...

Modeling population exposures to outdoor sources of hazardous air pollutants.

PubMed

Ozkaynak, Halûk; Palma, Ted; Touma, Jawad S; Thurman, James

2008-01-01

Accurate assessment of human exposures is an important part of environmental health effects research. However, most air pollution epidemiology studies rely upon imperfect surrogates of personal exposures, such as information based on available central-site outdoor concentration monitoring or modeling data. In this paper, we examine the limitations of using outdoor concentration predictions instead of modeled personal exposures for over 30 gaseous and particulate hazardous air pollutants (HAPs) in the US. The analysis uses the results from an air quality dispersion model (the ASPEN or Assessment System for Population Exposure Nationwide model) and an inhalation exposure model (the HAPEM or Hazardous Air Pollutant Exposure Model, Version 5), applied by the US. Environmental protection Agency during the 1999 National Air Toxic Assessment (NATA) in the US. Our results show that the total predicted chronic exposure concentrations of outdoor HAPs from all sources are lower than the modeled ambient concentrations by about 20% on average for most gaseous HAPs and by about 60% on average for most particulate HAPs (mainly, due to the exclusion of indoor sources from our modeling analysis and lower infiltration of particles indoors). On the other hand, the HAPEM/ASPEN concentration ratio averages for onroad mobile source exposures were found to be greater than 1 (around 1.20) for most mobile-source related HAPs (e.g. 1, 3-butadiene, acetaldehyde, benzene, formaldehyde) reflecting the importance of near-roadway and commuting environments on personal exposures to HAPs. The distribution of the ratios of personal to ambient concentrations was found to be skewed for a number of the VOCs and reactive HAPs associated with major source emissions, indicating the importance of personal mobility factors. We conclude that the increase in personal exposures from the corresponding predicted ambient levels tends to occur near locations where there are either major emission sources of HAPs

Sun-exposure knowledge and protection behavior in a North Chinese population: a questionnaire-based study.

PubMed

Cheng, Shaowei; Lian, Shi; Hao, Yongjing; Kang, Nan; Li, Shujuan; Nie, Yanjun; Zhang, Fan

2010-08-01

Sun exposure can cause a range of skin disorders. Skin damage can be prevented by following certain sun-protection measures. However, the majority of reported studies regarding sun-exposure knowledge and behavior have involved Caucasian populations. A self-administered multiple-choice questionnaire was administered. The questionnaire consisted of 13 questions aimed at evaluating people's knowledge, awareness, and protection behavior regarding sun exposure, and their knowledge of sunscreens and sunscreen use. A total of 623 volunteers were enrolled, including 238 men (38.2%) and 385 women (61.8%). The percentages of correct answers regarding sun-exposure knowledge and awareness ranged from 50% to 80%. Overall, 58.8% used sunscreen as a sun-protection measure in daily life, followed by use of protective clothes (49.3%), sun umbrella (45.4%), sunglasses (45.3%), and hat (42.2%). Fifty-two percent thought that suntan was harmful or not attractive. The mean sun-protection factor (SPF) of the sunscreens used was 27.7 +/- 9.2 and the mean UVA protection grade (PA) was 2.3 +/- 0.6. Knowledge and awareness concerning the harmful effects of sun exposure are widespread among the Chinese population. Sunscreens with high SPF and PA are the most commonly used among Chinese people. Clear sex differences were observed. There is a significant difference in the attitude toward suntan between Chinese and Caucasian populations.

[Exposure to VOCs in furniture factories in two populations in northern Colombia].

PubMed

Vargas-Ramos, Yadiris E; Marrugo-Negrete, José L

2014-01-01

Assess the exposure to volatile organic compounds (VOCs)in furniture handicraft factories workers in two populations of Sucre (Sincelejo and Sampués), North of Colombia.Identify possible signs and/or symptoms related to exposure to these contaminants. This was an analytical cross sectional study (2011), using a questionnaire. Study population consisted of 66 individuals, 41 exposed and 25 controls. Personal samples were collected for concentration quantifying of benzene, toluene, ethylbenzene and xylenes (both groups) and contrasting them with health effects possible attributed to these contaminants. The concentrations of benzene, toluene and m/p-xylene were higher in the exposed group (9.5 mg/m(3), 8.1 mg/m(3) and 12.1 mg/m(3))compared with the control group (0.2 mg/m(3), 0.3 mg/m(3) and 0.03 mg/m(3)). Muscular pain 82.9 % (PR=3.8; CI95%:1.2-11.8) and somnolence 65.9 % (PR=4.9; CI95%:1.7-14.7)were associated with a higher exposure.Factor such as mixtures of solvents (thinner) in the work and vehicles' traffic can contribute to these results. Several sources contribute to increases personal exposure of VOCs in furniture handicraft factories workers North of Colombia. Additionally, excessive use of these compounds may be generating adverse effects on the health of workers.

Impact of Prolonged Breastfeeding on Dental Caries: A Population-Based Birth Cohort Study.

PubMed

Peres, Karen Glazer; Nascimento, Gustavo G; Peres, Marco Aurelio; Mittinty, Murthy N; Demarco, Flavio Fernando; Santos, Ina Silva; Matijasevich, Alicia; Barros, Aluisio J D

2017-07-01

Few studies have assessed the effect of breastfeeding, bottle feeding, and sugar consumption on children's dental caries. We investigated whether the duration of breastfeeding is a risk factor for dental caries in the primary dentition, independently of sugar consumption. An oral health study ( n = 1303) nested in a birth cohort study was carried out in southern Brazil. The average number of decayed, missing, and filled primary tooth surfaces (dmfs) and severe early childhood caries (S-ECC: dmfs ≥6) were investigated at age 5 years. Breastfeeding was the main exposure collected at birth and at 3, 12, and 24 months of age. Data on sugar consumption were collected at 24, 48, and 60 months of age. Marginal structural modeling was used to estimate the controlled direct effect of breastfeeding (0-12, 13-23, and ≥24 months) on dmfs and on S-ECC. The prevalence of S-ECC was 23.9%. The mean number of dmfs was 4.05. Children who were breastfed for ≥24 months had a higher number of dmfs (mean ratio: 1.9; 95% confidence interval: 1.5-2.4) and a 2.4 times higher risk of having S-ECC (risk ratio: 2.4; 95% confidence interval: 1.7-3.3) than those who were breastfed up to 12 months of age. Breastfeeding between 13 and 23 months had no effect on dental caries. Prolonged breastfeeding increases the risk of having dental caries. Preventive interventions for dental caries should be established as early as possible because breastfeeding is beneficial for children's health. Mechanisms underlying this process should be investigated more deeply. Copyright © 2017 by the American Academy of Pediatrics.

Exposure Assessment Tools by Lifestages and Populations - General Population

EPA Pesticide Factsheets

EPA ExpoBox is a toolbox for exposure assessors. Its purpose is to provide a compendium of exposure assessment and risk characterization tools that will present comprehensive step-by-step guidance and links to relevant exposure assessment data bases

Evaluation of benzodiazepines and zolpidem in nails and their stability after prolonged exposure to chlorinated water.

PubMed

Moretti, Matteo; Andrello, Luisa; Visonà, Silvia; Vignali, Claudia; Groppi, Angelo; Freni, Francesca; Osculati, Antonio; Tajana, Luca; Morini, Luca

2018-04-15

The study aims the development and validation of a LC-MS/MS method for the identification and quantification of benzodiazepines and zolpidem in nails as alternative keratinized matrix to hair in long-term monitoring of anxiolytic and hypnotic drugs. Both fingernail and toenail samples (1-2 mm) were collected by clipping the excess overhang of the nail from volunteers and from postmortem cases. They were washed twice with organic solvents, dried under nitrogen stream, pulverized, immersed in a methanol solution (internal standard: diazepam-D5) and sonicated up to two hours. The solution was then direct injected in the LC-MS/MS system. Mass spectrometry was set in MRM mode, selecting two transitions for each substance. 32 analytes among benzodiazepines, metabolites and hypnotics were included in the list. The method fulfilled the internationally required criteria for validation. Limits of detection ranged from 0.03 pg/mg (zolpidem) to 13.1 pg/mg (bromazepam). 9 subjects under therapy were positive at 7 different benzodiazepines and/or metabolites (lorazepam, desalkylflurazepam, bromazepam, diazepam, alprazolam, lormetazepam and prazepam), while 5 molecules were measured in 4 postmortem cases (diazepam, desmethyldiazepam, delorazepam, 7-aminoclonazepam and zolpidem). In vitro experiments on eight authentic samples suggested that benzodiazepines in nails are influenced by the prolonged exposure to chlorinated water. Copyright © 2018 Elsevier B.V. All rights reserved.

Prolonged Exposure Therapy With Veterans and Active Duty Personnel Diagnosed With PTSD and Traumatic Brain Injury.

PubMed

Wolf, Gregory K; Kretzmer, Tracy; Crawford, Eric; Thors, Christina; Wagner, H Ryan; Strom, Thad Q; Eftekhari, Afsoon; Klenk, Megan; Hayward, Laura; Vanderploeg, Rodney D

2015-08-01

The present study used archival clinical data to analyze the delivery and effectiveness of prolonged exposure (PE) and ancillary services for posttraumatic stress disorder (PTSD) among Operation Enduring Freedom, Operation Iraqi Freedom, and Operation New Dawn veterans (N = 69) with histories of mild to severe traumatic brain injury (TBI). Data from standard clinical assessments of veterans and active duty personnel treated in both inpatient and outpatient programs at 2 Department of Veteran Affairs medical centers were examined. Symptoms were assessed with self-report measures of PTSD (PTSD Checklist) and depression (Beck Depression Inventory-II) before and throughout therapy. Mixed linear models were utilized to determine the slope of reported symptoms throughout treatment, and the effects associated with fixed factors such as site, treatment setting (residential vs. outpatient), and TBI severity were examined. Results demonstrated significant decreases in PTSD, B = -3.00, 95% CI [-3.22, -2.78]; t(210) = -13.5; p < .001, and in depressive symptoms, B = -1.46, 95% CI [-1.64, -1.28]; t(192) = -8.32; p < .001. The effects of PE treatment did not differ by clinical setting and participants with moderate to severe injuries reported more rapid gains than those with a history of mild TBI. The results provide evidence that PE may well be effective for veterans with PTSD and TBI. Copyright © 2015 International Society for Traumatic Stress Studies.

[Solar exposure time for sunburn in Mexican population].

PubMed

Castanedo Cázares, Juan Pablo; Torres Álvarez, Bertha; Sobrevilla Ondarza, Salvador; Ehnis Pérez, Adriana; Gordillo Moscoso, Antonio

2012-01-01

THe minimal erythemal dose (MED) quantifies an individual's sensitivity to UV radiation (UVR). To estimate it in our population and establish the time of exposure inducing it during daily activities would allow us to calculate risk intervals. From 2005-2012, the UV solar radiation was measured with terrestrial radiometry and compared to public UV index (UVI). We determined the MED in 90 individuals with the prevalent phototypes in Mexico (III, IV, V), and estimated the time needed for the development of sunburn. The average MED for phototype III was 39 (IC 95%: 35-42) mJ/cm2, for IV 48 (IC 95%:42-53) mJ/cm2, and for V was 84 (IC 95%:75-92) mJ/cm2 (ANOVA, p ≤ 0.001). Approximately, 80% of the daily UVR was accumulated between 10:00-16:00 h, and 77% of the annual UV dose is received between March-October. The public UVI had a high correlation with the one quantified at terrestrial level (r = 0.89; p ≤ 0.001). Mexico receives continuously high levels of UVR. Phototype III will present sunburn after 22-33 min in a summer day, while phototype V will require over one hour of exposure. This last group is at risk of chronic exposure without considering consequences.

[Secondary traumatization/trauma among employees in palliative care units--the products of prolonged repeated exposure to suffering and death].

PubMed

Samson, Tali; Shvartzman, Pesach

2012-11-01

The palliative care philosophy accepts the dying process as a natural phase in the life cycle and provides quality end of life care for terminal patients and their family members. Prolonged exposure to the physical symptoms and pain, as well as the psychological, spiritual, and existential suffering of the dying patient, may be fertile ground for the development of post-traumatic stress symptoms among palliative care teams. Work-related positive outcomes (such as compassion, satisfaction and meaning) and work-related negative outcomes (such as compassion fatigue, secondary traumatization and burnout) can exist side by side, and the unique balance between them will determine the quality of life of the worker. This review presents the current knowledge about the prevalence and causes of work-related stress outcomes among palliative care teams and measurement tools that are available. The literature review discusses secondary traumatization in palliative care teams and relevant messages for the development of treatment options, burnout prevention programs and support interventions for professionals who lead the care for terminal patients in Israel.

Changing US Population Demographics: What Does This Mean for Listeriosis Incidence and Exposure?

PubMed

Pohl, Aurelie M; Pouillot, Régis; Van Doren, Jane M

2017-09-01

Listeria monocytogenes is an important cause of foodborne illness hospitalization, fetal loss, and death in the United States. Listeriosis incidence rate varies significantly among population subgroups with pregnant women, older persons, and the Hispanic population having increased relative risks compared with the other subpopulations. Using estimated rates of listeriosis per subpopulation based on FoodNet data from 2004 to 2009, we evaluate the expected number of cases and incidence rates of listeriosis in the US population and the pregnant women subpopulation as the demographic composition changes over time with respect to ethnicity, pregnancy status, and age distribution. If the incidence rate per subpopulation is held constant, the overall US population listeriosis incidence rate would increase from 0.25 per 100,000 (95% confidence interval [CI]: 0.19-0.34) in 2010 to 0.28 (95% CI: 0.22-0.38) in 2020 and 0.32 (95% CI: 0.25-0.43) in 2030, because of the changes in the population structure. Similarly, the pregnancy-associated incidence rate is expected to increase from 4.0 per 100,000 pregnant women (95% CI: 2.5-6.5) in 2010 to 4.1 (95% CI: 2.6-6.7) in 2020 and 4.4 (95% CI: 2.7-7.2) in 2030 as the proportion of Hispanic pregnant women increases. We further estimate that a reduction of 12% in the exposure of the US population to L. monocytogenes would be needed to maintain a constant incidence rate from 2010 to 2020 (current trend), assuming infectivity (strain virulence distribution and individual susceptibility) is unchanged. To reduce the overall US population incidence rate by one-third (Healthy People 2020 goal) would require a reduction in exposure (or infectivity) to L. monocytogenes of 48% over the same time period. Reduction/elimination in exposure of pregnant and Hispanic subpopulations alone could not meet this target. This information may be useful in setting public health targets, developing risk management options, and in interpreting trends in the

Holocaust exposure and subsequent suicide risk: a population-based study.

PubMed

Bursztein Lipsicas, Cendrine; Levav, Itzhak; Levine, Stephen Z

2017-03-01

To examine the association between the extent of genocide exposure and subsequent suicide risk among Holocaust survivors. Persons born in Holocaust-exposed European countries during the years 1922-1945 that immigrated to Israel by 1965 were identified in the Population Registry (N = 209,429), and followed up for suicide (1950-2014). They were divided into three groups based on likely exposure to Nazi persecution: those who immigrated before (indirect; n = 20,229; 10%), during (partial direct; n = 17,189; 8%), and after (full direct; n = 172,061; 82%) World War II. Groups were contrasted for suicide risk, accounting for the extent of genocide in their respective countries of origin, high (>70%) or lower levels (<50%). Cox model survival analyses were computed examining calendar year at suicide. Sensitivity analyses were recomputed for two additional suicide-associated variables (age and years since immigration) for each exposure group. All analyses were adjusted for confounders. Survival analysis showed that compared to the indirect exposure group, the partial direct exposure group from countries with high genocide level had a statistically significant (P < .05) increased suicide risk for the main outcome (calendar year: HR 1.78, 95% CI 1.09, 2.90). This effect significantly (P < .05) replicated in two sensitivity analyses for countries with higher relative levels of genocide (age: HR 1.77, 95% CI 1.09, 2.89; years since immigration: HR 1.85, 95% CI 1.14, 3.02). The full direct exposure group was not at significant suicide risk compared to the indirect exposure group. Suicide associations for groups from countries with relative lower level of genocide were not statistically significant. This study partly converges with findings identifying Holocaust survivors (full direct exposure) as a resilient group. A tentative mechanism for higher vulnerability to suicide risk of the partial direct exposure group from countries with higher genocide exposure includes

Lifetime fluoridation exposure and dental caries experience in a military population.

PubMed

Mahoney, Gregory; Slade, Gary D; Kitchener, Scott; Barnett, Adrian

2008-12-01

While there is good evidence of caries-preventive benefits of fluoride in drinking water among children and adolescents, there is little information about effectiveness of water fluoridation among adults. To determine whether exposure to fluoride in drinking water is associated with caries experience in Australian Defence Force (ADF) personnel. Cross-sectional study of 876 deployable ADF personnel aged 17-56 years. At each person's mandatory annual dental examination, military dentists recorded the number of decayed, missing and filled teeth (DMFT) using visual, tactile and radiographic criteria. Participants also completed a questionnaire, listing residential locations in each year from 1964 to 2003. People were classified into four categories according to the percentage of their lifetime living in places with fluoridated water: <10%, 10% to <50%, 50% to <90% and > or =90%. Mean DMFT was compared among those categories of fluoridation exposure and the association was evaluated statistically using analysis of variance to adjust for age, sex, years of service and rank. Without adjustment for confounders, the mean DMFT (+/-95% confidence interval) was 6.3 +/- 0.8 for <10% fluoridation exposure, 7.8 +/- 0.8 for 10% to <50% exposure, 7.5 +/- 0.7 for 50% to <90% exposure and 4.6 +/- 0.6 for > or =90% exposure (P < 0.01). However, age was inversely associated with mean DMFT and in the <10% exposure group, 91% of people were aged <35 years. Service rank was also significantly associated with both fluoridation exposure and DMFT. After adjustment for all covariates, mean DMFT was 24% lower among people in the two groups with > or =50% exposure compared with the <10% exposure group. Degree of lifetime exposure to fluoridated drinking water was inversely associated with DMFT in a dose-response manner among this adult military population.

Cooperation between Strain-Specific and Broadly Neutralizing Responses Limited Viral Escape and Prolonged the Exposure of the Broadly Neutralizing Epitope

PubMed Central

Anthony, Colin; York, Talita; Bekker, Valerie; Matten, David; Selhorst, Philippe; Ferreria, Roux-Cil; Garrett, Nigel J.; Karim, Salim S. Abdool; Morris, Lynn; Wood, Natasha T.; Moore, Penny L.

2017-01-01

ABSTRACT V3-glycan-targeting broadly neutralizing antibodies (bNAbs) are a focus of HIV-1 vaccine development. Understanding the viral dynamics that stimulate the development of these antibodies can provide insights for immunogen design. We used a deep-sequencing approach, together with neutralization phenotyping, to investigate the rate and complexity of escape from V3-glycan-directed bNAbs compared to overlapping early strain-specific neutralizing antibody (ssNAb) responses to the V3/C3 region in donor CAP177. Escape from the ssNAb response occurred rapidly via an N334-to-N332 glycan switch, which took just 7.5 weeks to reach >50% frequency. In contrast, escape from the bNAbs was mediated via multiple pathways and took longer, with escape first occurring through an increase in V1 loop length, which took 46 weeks to reach 50% frequency, followed by an N332-to-N334 reversion, which took 66 weeks. Importantly, bNAb escape was incomplete, with contemporaneous neutralization observed up to 3 years postinfection. Both the ssNAb response and the bNAb response were modulated by the presence/absence of the N332 glycan, indicating an overlap between the two epitopes. Thus, selective pressure by ssNAbs to maintain the N332 glycan may have constrained the bNAb escape pathway. This slower and incomplete viral escape resulted in prolonged exposure of the bNAb epitope, which may in turn have aided the maturation of the bNAb lineage. IMPORTANCE The development of an HIV-1 vaccine is of paramount importance, and broadly neutralizing antibodies are likely to be a key component of a protective vaccine. The V3-glycan-targeting bNAb responses are among the most promising vaccine targets, as they are commonly elicited during infection. Understanding the interplay between viral evolution and the development of these antibodies provides insights that may guide immunogen design. Our work contrasted the dynamics of the early strain-specific antibodies and the later broadly neutralizing

Calibrating a population-based job-exposure matrix using inspection measurements to estimate historical occupational exposure to lead for a population-based cohort in Shanghai, China

PubMed Central

Koh, Dong-Hee; Bhatti, Parveen; Coble, Joseph B.; Stewart, Patricia A; Lu, Wei; Shu, Xiao-Ou; Ji, Bu-Tian; Xue, Shouzheng; Locke, Sarah J.; Portengen, Lutzen; Yang, Gong; Chow, Wong-Ho; Gao, Yu-Tang; Rothman, Nathaniel; Vermeulen, Roel; Friesen, Melissa C.

2012-01-01

The epidemiologic evidence for the carcinogenicity of lead is inconsistent and requires improved exposure assessment to estimate risk. We evaluated historical occupational lead exposure for a population-based cohort of women (n=74,942) by calibrating a job-exposure matrix (JEM) with lead fume (n=20,084) and lead dust (n=5,383) measurements collected over four decades in Shanghai, China. Using mixed-effect models, we calibrated intensity JEM ratings to the measurements using fixed-effects terms for year and JEM rating. We developed job/industry-specific estimates from the random-effects terms for job and industry. The model estimates were applied to subjects’ jobs when the JEM probability rating was high for either job or industry; remaining jobs were considered unexposed. The models predicted that exposure increased monotonically with JEM intensity rating and decreased 20–50-fold over time. The cumulative calibrated JEM estimates and job/industry-specific estimates were highly correlated (Pearson correlation=0.79–0.84). Overall, 5% of the person-years and 8% of the women were exposed to lead fume; 2% of the person-years and 4% of the women were exposed to lead dust. The most common lead-exposed jobs were manufacturing electronic equipment. These historical lead estimates should enhance our ability to detect associations between lead exposure and cancer risk in future epidemiologic analyses. PMID:22910004

Correlates of exposure to second-hand smoke in an urban Mediterranean population

PubMed Central

Twose, Jorge; Schiaffino, Anna; García, Montse; Borras, Josep Maria; Fernández, Esteve

2007-01-01

Background To describe the socio-demographic factors associated with exposure to second-hand smoke (SHS) in different settings (home, leisure, and workplace). Methods We analysed cross-sectional data on self-reported SHS exposure in 1059 non-daily smokers interviewed in the Cornellà Health Interview Survey Follow-up Study in 2002. We calculated age-adjusted prevalence rates and prevalence rate ratios of SHS exposure at home, at the workplace, during leisure time, and in any of these settings. Results The age-standardized prevalence rate of SHS exposure in any setting was 69.5% in men and 62.9% in women. Among men, 25.9% reported passive smoking at home, 55.1% during leisure time, and 34.0% at the workplace. Among women, prevalence rates in these settings were 34.1%, 44.3% and 30.1%, respectively. Overall exposure to SHS decreased with age in both men and women. In men, SHS exposure was related to marital status, physical activity, smoking, and alcohol intake. In women, SHS exposure was related to educational level, marital status, occupational status, self-perceived health, smoking-related illness, and alcohol intake. Conclusion The prevalence of SHS exposure in this population was high. The strongest association with exposure were found for age and occupational status in men, and age and educational level in women. PMID:17683585

Usage patterns of aromatherapy among the French general population: A descriptive study focusing on dermal exposure.

PubMed

Dornic, N; Ficheux, A S; Roudot, A C; Saboureau, D; Ezzedine, K

2016-04-01

Although likely benefits of aromatherapy are well documented, little is known about essential oils consumption and exposure to molecules present in the oils. The aim of our study was to determine usage patterns of 12 types of essential oils among a quite large panel, sorted per sex and quintile of age from birth to 70. A survey was conducted in September 2014 among 1507 French individuals, selected to build a representative panel of the general population. The key point of our study, apart from the fact that it has never been done among general population, was the focus on dermal exposure. Information about types of essential oils used, skin areas exposed, frequencies and quantities were collected. Our work revealed that some sub-populations could be significantly exposed to molecules of toxicological concern, especially in terms of skin sensitization. This work is the first step to assess human exposure to these molecules, and will help safety authorities and risk managers to protect the population. Copyright © 2016 Elsevier Inc. All rights reserved.

The Public Health Exposome: A Population-Based, Exposure Science Approach to Health Disparities Research

PubMed Central

Juarez, Paul D.; Matthews-Juarez, Patricia; Hood, Darryl B.; Im, Wansoo; Levine, Robert S.; Kilbourne, Barbara J.; Langston, Michael A.; Al-Hamdan, Mohammad Z.; Crosson, William L.; Estes, Maurice G.; Estes, Sue M.; Agboto, Vincent K.; Robinson, Paul; Wilson, Sacoby; Lichtveld, Maureen Y.

2014-01-01

The lack of progress in reducing health disparities suggests that new approaches are needed if we are to achieve meaningful, equitable, and lasting reductions. Current scientific paradigms do not adequately capture the complexity of the relationships between environment, personal health and population level disparities. The public health exposome is presented as a universal exposure tracking framework for integrating complex relationships between exogenous and endogenous exposures across the lifespan from conception to death. It uses a social-ecological framework that builds on the exposome paradigm for conceptualizing how exogenous exposures “get under the skin”. The public health exposome approach has led our team to develop a taxonomy and bioinformatics infrastructure to integrate health outcomes data with thousands of sources of exogenous exposure, organized in four broad domains: natural, built, social, and policy environments. With the input of a transdisciplinary team, we have borrowed and applied the methods, tools and terms from various disciplines to measure the effects of environmental exposures on personal and population health outcomes and disparities, many of which may not manifest until many years later. As is customary with a paradigm shift, this approach has far reaching implications for research methods and design, analytics, community engagement strategies, and research training. PMID:25514145

Effects of exposure to oil spills on human health: Updated review.

PubMed

Laffon, Blanca; Pásaro, Eduardo; Valdiglesias, Vanessa

2016-01-01

Oil spills may involve health risks for people participating in the cleanup operations and coastal inhabitants, given the toxicological properties of the oil components. In spite of this, only after a few major oil spills (crude oil or fuel oil no. 6) have studies on effects of exposure to diverse aspects of human health been performed. Previously, Aguilera et al. (2010) examined all documents published to that date dealing with any type of human health outcome in populations exposed to oil spills. The aim of the present review was to compile all new information available and determine whether evidence reported supports the existence of an association between exposure and adverse human health risks. Studies were classified in three groups according to type of health outcome addressed: (i) effects on mental health, (ii) physical/physiological effects, and (iii) genotoxic, immunotoxic, and endocrine toxicity. New studies published on oil-spill-exposed populations-coastal residents in the vicinity of the spills or participants in cleanup operations-provide additional support to previous evidence on adverse health effects related to exposure regarding different parameters in all three categories considered. Some of the observed effects even indicated that several symptoms may persist for some years after exposure. Hence, (1) health protection in these individuals should be a matter of concern; and (2) health risk assessment needs to be carried out not only at the time of exposure but also for prolong periods following exposure, to enable early detection of any potential exposure-related harmful effects.

Consumption of cosmetic products by the French population. Third part: Product exposure amount.

PubMed

Dornic, N; Ficheux, A S; Roudot, A C

2017-08-01

A recent study in France provided valuable data on the frequency and amount of use of cosmetic products (Ficheux et al., 2015, 2016a). The aim of the present study was to generate Product Exposure Amount data, i.e. the amounts of cosmetics applied to the skin among the French population using the raw data collected during the previous enquiry. These data are useful to derive Consumer exposure level data which are paramount for skin sensitization risk assessments. Exposure data were generated for 69 different cosmetics, classified as products for the hair, face, buccal hygiene, hands, feet, body, shaving and depilation, sunscreens as well as products specifically intended for babies. Exposure was calculated using a probabilistic Monte Carlo method. The main strength of this work was the break-down of data by age and sex. The results showed that some data used by the International Fragrance Association in skin sensitization risk assessments, in particular facial care products and deodorants, could be unsuitable for the protection of French consumers. For the first time, data were also generated for products intended for babies' nappy area. These data will be useful for the implementation of the Quantitative Risk Assessment for skin sensitization among the French population. Copyright © 2017 Elsevier Ltd. All rights reserved.

Climate change and health: Indoor heat exposure in vulnerable populations

DOE Office of Scientific and Technical Information (OSTI.GOV)

White-Newsome, Jalonne L., E-mail: jalonne@umich.edu; Sanchez, Brisa N., E-mail: brisa@umich.edu; Jolliet, Olivier, E-mail: ojolliet@umich.edu

2012-01-15

Introduction: Climate change is increasing the frequency of heat waves and hot weather in many urban environments. Older people are more vulnerable to heat exposure but spend most of their time indoors. Few published studies have addressed indoor heat exposure in residences occupied by an elderly population. The purpose of this study is to explore the relationship between outdoor and indoor temperatures in homes occupied by the elderly and determine other predictors of indoor temperature. Materials and methods: We collected hourly indoor temperature measurements of 30 different homes; outdoor temperature, dewpoint temperature, and solar radiation data during summer 2009 inmore » Detroit, MI. We used mixed linear regression to model indoor temperatures' responsiveness to weather, housing and environmental characteristics, and evaluated our ability to predict indoor heat exposures based on outdoor conditions. Results: Average maximum indoor temperature for all locations was 34.85 Degree-Sign C, 13.8 Degree-Sign C higher than average maximum outdoor temperature. Indoor temperatures of single family homes constructed of vinyl paneling or wood siding were more sensitive than brick homes to outdoor temperature changes and internal heat gains. Outdoor temperature, solar radiation, and dewpoint temperature predicted 38% of the variability of indoor temperatures. Conclusions: Indoor exposures to heat in Detroit exceed the comfort range among elderly occupants, and can be predicted using outdoor temperatures, characteristics of the housing stock and surroundings to improve heat exposure assessment for epidemiological investigations. Weatherizing homes and modifying home surroundings could mitigate indoor heat exposure among the elderly.« less

Future Coastal Population Growth and Exposure to Sea-Level Rise and Coastal Flooding - A Global Assessment

PubMed Central

Neumann, Barbara; Vafeidis, Athanasios T.; Zimmermann, Juliane; Nicholls, Robert J.

2015-01-01

Coastal zones are exposed to a range of coastal hazards including sea-level rise with its related effects. At the same time, they are more densely populated than the hinterland and exhibit higher rates of population growth and urbanisation. As this trend is expected to continue into the future, we investigate how coastal populations will be affected by such impacts at global and regional scales by the years 2030 and 2060. Starting from baseline population estimates for the year 2000, we assess future population change in the low-elevation coastal zone and trends in exposure to 100-year coastal floods based on four different sea-level and socio-economic scenarios. Our method accounts for differential growth of coastal areas against the land-locked hinterland and for trends of urbanisation and expansive urban growth, as currently observed, but does not explicitly consider possible displacement or out-migration due to factors such as sea-level rise. We combine spatially explicit estimates of the baseline population with demographic data in order to derive scenario-driven projections of coastal population development. Our scenarios show that the number of people living in the low-elevation coastal zone, as well as the number of people exposed to flooding from 1-in-100 year storm surge events, is highest in Asia. China, India, Bangladesh, Indonesia and Viet Nam are estimated to have the highest total coastal population exposure in the baseline year and this ranking is expected to remain largely unchanged in the future. However, Africa is expected to experience the highest rates of population growth and urbanisation in the coastal zone, particularly in Egypt and sub-Saharan countries in Western and Eastern Africa. The results highlight countries and regions with a high degree of exposure to coastal flooding and help identifying regions where policies and adaptive planning for building resilient coastal communities are not only desirable but essential. Furthermore, we

Future coastal population growth and exposure to sea-level rise and coastal flooding--a global assessment.

PubMed

Neumann, Barbara; Vafeidis, Athanasios T; Zimmermann, Juliane; Nicholls, Robert J

2015-01-01

Coastal zones are exposed to a range of coastal hazards including sea-level rise with its related effects. At the same time, they are more densely populated than the hinterland and exhibit higher rates of population growth and urbanisation. As this trend is expected to continue into the future, we investigate how coastal populations will be affected by such impacts at global and regional scales by the years 2030 and 2060. Starting from baseline population estimates for the year 2000, we assess future population change in the low-elevation coastal zone and trends in exposure to 100-year coastal floods based on four different sea-level and socio-economic scenarios. Our method accounts for differential growth of coastal areas against the land-locked hinterland and for trends of urbanisation and expansive urban growth, as currently observed, but does not explicitly consider possible displacement or out-migration due to factors such as sea-level rise. We combine spatially explicit estimates of the baseline population with demographic data in order to derive scenario-driven projections of coastal population development. Our scenarios show that the number of people living in the low-elevation coastal zone, as well as the number of people exposed to flooding from 1-in-100 year storm surge events, is highest in Asia. China, India, Bangladesh, Indonesia and Viet Nam are estimated to have the highest total coastal population exposure in the baseline year and this ranking is expected to remain largely unchanged in the future. However, Africa is expected to experience the highest rates of population growth and urbanisation in the coastal zone, particularly in Egypt and sub-Saharan countries in Western and Eastern Africa. The results highlight countries and regions with a high degree of exposure to coastal flooding and help identifying regions where policies and adaptive planning for building resilient coastal communities are not only desirable but essential. Furthermore, we

Brominated flame retardants - Exposure and risk assessment for the general population.

PubMed

Fromme, H; Becher, G; Hilger, B; Völkel, W

2016-01-01

Brominated flame retardants (BFRs) are a large group of different substances used in numerous products to prevent fire hazards. Some of them are persistent in the environment, accumulate in the food chain and are of toxicological concern, while for others current data are limited. Meanwhile, BFRs have been found in many environmental media, foods, and biota including humans. This review presents recent findings obtained from monitoring data in environmental media relevant for human exposure, as well as dietary exposure. In this context, concentrations in indoor and ambient air and in house dust are outlined. Furthermore, we summarize human biomonitoring data on BFR levels in blood and breast milk. Current estimates of the overall exposure of the general population using different relevant subsets are also addressed. All of these data are discussed in relation to currently available toxicological reference values used for risk assessment purposes. Obviously, the exposure of the general population varies considerably in different parts of the world and even within countries. Polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCD) show the highest intake during infancy. While the highest intake for BDE 47 for all groups was observed in the US, the total BDE 209 and HBCD intake was highest in the UK. For HBCD and all PBDEs except BDE 209, diet accounts for a large proportion of the total intake during infancy in all countries. With regard to toddlers and adults, the contribution of diet to total intake is high in Germany and the UK, while in the US, the high concentrations of PBDE in dust resulted in a notably smaller proportion of the intake being attributed to diet. Copyright © 2015 Elsevier GmbH. All rights reserved.

Predictive Analytics for Identification of Patients at Risk for QT Interval Prolongation - A Systematic Review.

PubMed

Tomaselli Muensterman, Elena; Tisdale, James E

2018-06-08

Prolongation of the heart rate-corrected QT (QTc) interval increases the risk for torsades de pointes (TdP), a potentially fatal arrhythmia. The likelihood of TdP is higher in patients with risk factors, which include female sex, older age, heart failure with reduced ejection fraction, hypokalemia, hypomagnesemia, concomitant administration of ≥ 2 QTc interval-prolonging medications, among others. Assessment and quantification of risk factors may facilitate prediction of patients at highest risk for developing QTc interval prolongation and TdP. Investigators have utilized the field of predictive analytics, which generates predictions using techniques including data mining, modeling, machine learning, and others, to develop methods of risk quantification and prediction of QTc interval prolongation. Predictive analytics have also been incorporated into clinical decision support (CDS) tools to alert clinicians regarding patients at increased risk of developing QTc interval prolongation. The objectives of this paper are to assess the effectiveness of predictive analytics for identification of patients at risk of drug-induced QTc interval prolongation, and to discuss the efficacy of incorporation of predictive analytics into CDS tools in clinical practice. A systematic review of English language articles (human subjects only) was performed, yielding 57 articles, with an additional 4 articles identified from other sources; a total of 10 articles were included in this review. Risk scores for QTc interval prolongation have been developed in various patient populations including those in cardiac intensive care units (ICUs) and in broader populations of hospitalized or health system patients. One group developed a risk score that includes information regarding genetic polymorphisms; this score significantly predicted TdP. Development of QTc interval prolongation risk prediction models and incorporation of these models into CDS tools reduces the risk of QTc interval

POPULATION-BASED EXPOSURE MEASUREMENTS IN ARIZONA: A PHASE FIELD STUDY IN SUPPORT OF THE NATIONAL HUMAN EXPOSURE ASSESSMENT SURVEY

EPA Science Inventory

The objectives of this field study are to determine the distributions of total human exposures to multi-media pollutants in the classes of metals, pesticides, and volatile organic compounds (VOCs) by studying a proportionate-based sample of the total population (with a nested des...

QTc prolongation after brain surgery.

PubMed

Capparelli, Federico J; Abello, Mauricio; Patricio Maskin, L; Arista, Eugenia; Hlavnicka, Alejandro; Diaz, Maria Fernanda; Varela, Daniel; Wainsztein, Nestor A

2013-03-01

Abnormalities observed in the electrocardiogram (ECG) after acute central nervous system (CNS) events have been reported. Our objective was to assess the incidence of heart rate-corrected QT interval (QTc) prolongation in patients admitted to the intensive care unit (ICU) after brain surgery. Admission standard 12-lead ECGs were analyzed blinded to patient data. The QT interval was measured and Bazzett's formula was used to obtain QTc. Prolonged QTc was defined as ≧450 ms. We included 114 patients in the study. The mean age was 49±17 years. Brain neoplasm was the surgical indication in 90% of the patients. The mean QTc was 470±42 ms. Prolonged QTc was found in 71% patients. The heart rate-corrected QT interval was between 450 ms and 500 ms in 52% and >500 ms in 19% of the patients. The heart rate and concentration of serum glucose were higher in the prolonged QTc group. Only 7·5% of all patients had hypokalemia (≤3 mEq/l). In the prolonged QTc group 9·2% had hypokalemia compared to 3·2% in normal QTc patients (P = 0·406). There were no significant associations between categories of QTc and the serum levels of creatinine, magnesium, calcium, sodium, or pH. Phenytoin and metoclopramide were not frequently used in patients with prolonged QTc. This study supports our hypothesis that prolonged QTc is frequently observed after a brain surgery. Hypokalemia, hypocalcaemia, and drugs such as metoclopramide or phenytoin could not explain the high incidence of prolonged QTc. Brain injury during a surgical procedure may be one of the primary causes of QTc prolongation after neurosurgery.

Dietary acrylamide exposure of the French population: results of the second French Total Diet Study.

PubMed

Sirot, Véronique; Hommet, Frédéric; Tard, Alexandra; Leblanc, Jean-Charles

2012-03-01

Acrylamide is a heat-induced carcinogen compound that is found in some foods consequently to cooking or other thermal processes. In the second French Total Diet Study (TDS), acrylamide was analysed in 192 food samples collected in mainland France to be representative of the population diet and prepared "as consumed". Highest mean concentrations were found in potato chips/crisps (954 μg/kg), French fries and other fried potatoes (724 μg/kg), and salted biscuits other than potato chips (697 μg/kg). Exposure of general adult and child populations was assessed by combining analytical results with national consumption data. Mean acrylamide exposure was assessed to be 0.43±0.33 μg/kg of body weight (bw) per day for adults and 0.69±0.58 μg/kg bw/day for children. Although the exposure assessed is lower than in previous evaluations, the calculated margins of exposure, based on benchmark dose limits defined for carcinogenic effects, remain very low especially for young children (below 100 at the 95th percentile of exposure), indicating a health concern. It is therefore advisable to continue efforts in order to reduce dietary exposure to acrylamide. Copyright © 2012 Elsevier Ltd. All rights reserved.

Modeling Population-Level Consequences of Polychlorinated Biphenyl Exposure in East Greenland Polar Bears.

PubMed

Pavlova, Viola; Grimm, Volker; Dietz, Rune; Sonne, Christian; Vorkamp, Katrin; Rigét, Frank F; Letcher, Robert J; Gustavson, Kim; Desforges, Jean-Pierre; Nabe-Nielsen, Jacob

2016-01-01

Polychlorinated biphenyls (PCBs) can cause endocrine disruption, cancer, immunosuppression, or reproductive failure in animals. We used an individual-based model to explore whether and how PCB-associated reproductive failure could affect the dynamics of a hypothetical polar bear (Ursus maritimus) population exposed to PCBs to the same degree as the East Greenland subpopulation. Dose-response data from experimental studies on a surrogate species, the mink (Mustela vision), were used in the absence of similar data for polar bears. Two alternative types of reproductive failure in relation to maternal sum-PCB concentrations were considered: increased abortion rate and increased cub mortality. We found that the quantitative impact of PCB-induced reproductive failure on population growth rate depended largely on the actual type of reproductive failure involved. Critical potencies of the dose-response relationship for decreasing the population growth rate were established for both modeled types of reproductive failure. Comparing the model predictions of the age-dependent trend of sum-PCBs concentrations in females with actual field measurements from East Greenland indicated that it was unlikely that PCB exposure caused a high incidence of abortions in the subpopulation. However, on the basis of this analysis, it could not be excluded that PCB exposure contributes to higher cub mortality. Our results highlight the necessity for further research on the possible influence of PCBs on polar bear reproduction regarding their physiological pathway. This includes determining the exact cause of reproductive failure, i.e., in utero exposure versus lactational exposure of offspring; the timing of offspring death; and establishing the most relevant reference metrics for the dose-response relationship.

Assessing multimedia/multipathway exposures to inorganic arsenic at population and individual level using MERLIN-Expo.

PubMed

Van Holderbeke, Mirja; Fierens, Tine; Standaert, Arnout; Cornelis, Christa; Brochot, Céline; Ciffroy, Philippe; Johansson, Erik; Bierkens, Johan

2016-10-15

In this study, we report on model simulations performed using the newly developed exposure tool, MERLIN-Expo, in order to assess inorganic arsenic (iAs) exposure to adults resulting from past emissions by non-ferrous smelters in Belgium (Northern Campine area). Exposure scenarios were constructed to estimate external iAs exposure as well as the toxicologically relevant As (tAs, i.e., iAs, MMA and DMA) body burden in adults living in the vicinity of the former industrial sites as compared to adults living in adjacent areas and a reference area. Two scenarios are discussed: a first scenario studying exposure to iAs at the aggregated population level and a second scenario studying exposure at the individual level for a random sub-sample of subjects in each of the three different study areas. These two scenarios only differ in the type of human related input data (i.e., time-activity data, ingestion rates and consumption patterns) that were used, namely averages (incl. probability density functions, PDFs) in the simulation at population level and subject-specific values in the simulation at individual level. The model predictions are shown to be lower than the corresponding biomonitoring data from the monitoring campaign. Urinary tAs levels in adults, irrespective of the area they lived in, were under-predicted by MERLIN-Expo by 40% on average. The model predictions for individual adults, by contrast, under-predict the biomonitoring data by 7% on average, but with more important under-predictions for subjects at the upper end of exposure. Still, average predicted urinary tAs levels from the simulations at population level and at individual level overlap, and, at least for the current case, lead to similar conclusions. These results constitute a first and partial verification of the model performance of MERLIN-Expo when dealing with iAs in a complex site-specific exposure scenario, and demonstrate the robustness of the modelling tool for these situations. Copyright �

Web-PE: Internet-Delivered Prolonged Exposure Therapy for PTSD

DTIC Science & Technology

2015-10-01

order to meet the growing demand for effective and efficient treatment for posttraumatic stress disorder ( PTSD ) in a timely manner. Web-treatments...posttraumatic stress disorder ( PTSD ) in a timely manner. Effective EBTs for PTSD are available, but barriers to accessing care can deter military...Exposure, combat, psychological treatment, military, psychotherapy, trauma, posttraumatic stress , posttraumatic stress disorder 16. SECURITY

Hypoxic ventilatory sensitivity in men is not reduced by prolonged hyperoxia (Predictive Studies V and VI)

NASA Technical Reports Server (NTRS)

Gelfand, R.; Lambertsen, C. J.; Clark, J. M.; Hopkin, E.

1998-01-01

Potential adverse effects on the O2-sensing function of the carotid body when its cells are exposed to toxic O2 pressures were assessed during investigations of human organ tolerance to prolonged continuous and intermittent hyperoxia (Predictive Studies V and VI). Isocapnic hypoxic ventilatory responses (HVR) were determined at 1.0 ATA before and after severe hyperoxic exposures: 1) continuous O2 breathing at 1.5, 2.0, and 2.5 ATA for 17.7, 9.0, and 5.7 h and 2) intermittent O2 breathing at 2.0 ATA (30 min O2-30 min normoxia) for 14.3 O2 h within 30-h total time. Postexposure curvature of HVR hyperbolas was not reduced compared with preexposure controls. The hyperbolas were temporarily elevated to higher ventilations than controls due to increments in respiratory frequency that were proportional to O2 exposure time, not O2 pressure. In humans, prolonged hyperoxia does not attenuate the hypoxia-sensing function of the peripheral chemoreceptors, even after exposures that approach limits of human pulmonary and central nervous system O2 tolerance. Current applications of hyperoxia in hyperbaric O2 therapy and in subsea- and aerospace-related operations are guided by and are well within these exposure limits.

Electronic cigarette use and exposure in the pediatric population.

PubMed

Collaco, Joseph M; Drummond, M Bradley; McGrath-Morrow, Sharon A

2015-02-01

Electronic cigarette (e-cigarette) use has gained recent widespread popularity and acceptance in the general population. What effect e-cigarettes may have on pediatric health remains unknown. Although many jurisdictions have laws that prevent the sale of e-cigarettes to minors and the use of e-cigarettes in public places, infants, children, and adolescents are increasingly exposed to them. In this pediatric-focused review, we discuss the history of these devices, user demographics, known health effects, and current legislative efforts to protect minors from exposure.

Electronic Cigarette Use and Exposure in the Pediatric Population

PubMed Central

Collaco, Joseph M.; Drummond, M. Bradley; McGrath-Morrow, Sharon A.

2017-01-01

Electronic cigarette (e-cigarette) use has gained recent widespread popularity and acceptance in the general population. What effect e-cigarettes may have on pediatric health remains unknown. Although many jurisdictions have laws that prevent the sale of e-cigarettes to minors and the use of e-cigarettes in public places, infants, children, and adolescents are increasingly exposed to them. In this pediatric-focused review, we discuss the history of these devices, user demographics, known health effects, and current legislative efforts to protect minors from exposure. PMID:25546699

ASSESSMENT OF CADMIUM EXPOSURE AND TOXICITY RISK IN AN AMERICAN VEGETARIAN POPULATION

EPA Science Inventory

It has been postulated that nonvegetarians may be exposed to less cadmium than vegetarians because of the cadmium-poor meat in their diet. This study attempts to test this possibility by measuring the cadmium exposure and accumulation in a population subgroup that includes many v...

Incidence of nephrolithiasis in relation to environmental exposure to lead and cadmium in a population study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hara, Azusa; Yang, Wen-Yi; Petit, Thibault

Whether environmental exposure to nephrotoxic agents that potentially interfere with calcium homeostasis, such as lead and cadmium, contribute to the incidence of nephrolithiasis needs further clarification. We investigated the relation between nephrolithiasis incidence and environmental lead and cadmium exposure in a general population. In 1302 participants randomly recruited from a Flemish population (50.9% women; mean age, 47.9 years), we obtained baseline measurements (1985–2005) of blood lead (BPb), blood cadmium (BCd), 24-h urinary cadmium (UCd) and covariables. We monitored the incidence of kidney stones until October 6, 2014. We used Cox regression to calculate multivariable-adjusted hazard ratios for nephrolithiasis. At baseline,more » geometric mean BPb, BCd and UCd was 0.29 µmol/L, 9.0 nmol/L, and 8.5 nmol per 24 h, respectively. Over 11.5 years (median), nephrolithiasis occurred in 40 people. Contrasting the low and top tertiles of the distributions, the sex- and age-standardized rates of nephrolithiasis expressed as events per 1000 person-years were 0.68 vs. 3.36 (p=0.0016) for BPb, 1.80 vs. 3.28 (p=0.11) for BCd, and 1.65 vs. 2.95 (p=0.28) for UCd. In continuous analysis, with adjustments applied for sex, age, serum magnesium, and 24-h urinary volume and calcium, the hazard ratios expressing the risk associated with a doubling of the exposure biomarkers were 1.35 (p=0.015) for BPb, 1.13 (p=0.22) for BCd, and 1.23 (p=0.070) for UCd. In conclusion, our results suggest that environmental lead exposure is a risk factor for nephrolithiasis in the general population. - Highlights: • Prevalence and incidence rates of nephrolithiasis are increasing worldwide. • Lead and cadmium interfere with calcium homeostasis and might cause nephrolithiasis. • Environmental exposure to lead, not cadmium, predicts nephrolithiasis in the population. • Safety standards for environmental lead exposure need to account for nephrolithiasis. • Reducing environmental

Prolonged exposure of cortical neurons to oligomeric amyloid-β impairs NMDA receptor function via NADPH oxidase-mediated ROS production: protective effect of green tea (–)-epigallocatechin-3-gallate

PubMed Central

He, Yan; Cui, Jiankun; Lee, James C-M; Ding, Shinghua; Chalimoniuk, Malgorzata; Simonyi, Agnes; Sun, Albert Y; Gu, Zezong; Weisman∥, Gary A; Gibson Wood, W; Sun, Grace Y

2011-01-01

Excessive production of Aβ (amyloid β-peptide) has been shown to play an important role in the pathogenesis of AD (Alzheimer's disease). Although not yet well understood, aggregation of Aβ is known to cause toxicity to neurons. Our recent study demonstrated the ability for oligomeric Aβ to stimulate the production of ROS (reactive oxygen species) in neurons through an NMDA (N-methyl-d-aspartate)-dependent pathway. However, whether prolonged exposure of neurons to aggregated Aβ is associated with impairment of NMDA receptor function has not been extensively investigated. In the present study, we show that prolonged exposure of primary cortical neurons to Aβ oligomers caused mitochondrial dysfunction, an attenuation of NMDA receptor-mediated Ca2+ influx and inhibition of NMDA-induced AA (arachidonic acid) release. Mitochondrial dysfunction and the decrease in NMDA receptor activity due to oligomeric Aβ are associated with an increase in ROS production. Gp91ds-tat, a specific peptide inhibitor of NADPH oxidase, and Mn(III)-tetrakis(4-benzoic acid)-porphyrin chloride, an ROS scavenger, effectively abrogated Aβ-induced ROS production. Furthermore, Aβ-induced mitochondrial dysfunction, impairment of NMDA Ca2+ influx and ROS production were prevented by pre-treatment of neurons with EGCG [(−)-epigallocatechin-3-gallate], a major polyphenolic component of green tea. Taken together, these results support a role for NADPH oxidase-mediated ROS production in the cytotoxic effects of Aβ, and demonstrate the therapeutic potential of EGCG and other dietary polyphenols in delaying onset or retarding the progression of AD. PMID:21434871

Ultraviolet light sensitivity and prolonged UVR-erythema

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wilson, P.D.; Kaidbey, K.H.; Kligman, A.M.

The erythema and tanning responses in skin type I (n . 15) and skin type IV (n . 17) have been compared in caucasoids following a single exposure to solar simulated radiation. The former sunburn easily and do not tan while the latter do not burn and tan readily. The dose of radiation was 5 times the Minimal Erythema Dose (MED). The test sites were the extensor aspect of the forearm (exposed site) and flexor aspect of the upper arm (nonexposed site). The responses were monitored at 24 and 48 hr and then twice weekly for 8 weeks. The groupmore » of skin type I individuals had a lower MED and a much more prolonged erythema on both the exposed and nonexposed sites than the group of type IV individuals. All differences were highly significant (p less than 0.005). After 4 weeks erythema remained present in all of the type I subjects but had disappeared in 16 of the 17 type IV subjects. Within the groups there was no difference between erythema duration on exposed vs. nonexposed sites, but there was a highly significant difference (p less than 0.005) between the lower MED on the upper arm and higher MED on the forearm. These results contrast with those of other reports in which prolonged erythema could not be correlated with fair complexion, sunburn sensitivity, ethnic background, or skin type but was instead found to be a distinct feature of persons who had developed nonmelanoma skin cancer. Since prolonged erythema is related to skin type it is therefore not solely a feature of patients with skin cancer.« less

Wild mushroom exposures in Florida, 2003-2007.

PubMed

Kintziger, Kristina W; Mulay, Prakash; Watkins, Sharon; Schauben, Jay; Weisman, Richard; Lewis-Younger, Cynthia; Blackmore, Carina

2011-01-01

Exposure to wild mushrooms can lead to serious illness and death. However, there is little information on the epidemiology of mushroom exposures nationwide, as there is no specific surveillance for this outcome. We described mushroom exposures in Florida using available data sources. We performed a population-based study of mushroom exposure calls to the Florida Poison Information Center Network (FPICN) and cases of mushroom poisoning reported in hospital inpatient and emergency department (ED) data from 2003 through 2007. There were 1,538 unduplicated mushroom exposures reported during this period, including 1,355 exposure calls and 428 poisoning cases. Most exposures reported to FPICN occurred in children ≤6 years of age (45%) and males (64%), and most were unintentional ingestions (60%). Many exposures resulted in no effect (35%), although 21% reported mild symptoms that resolved rapidly, 23% reported prolonged/systemic (moderate) symptoms, and 1% reported life-threatening effects. Most calls occurred when in or en route to a health-care facility (43%). More than 71% of poisonings identified in hospital records were managed in an ED, and most occurred in young adults 16-25 years of age (49%), children ≤6 years of age (21%), adults >25 years of age (21%), and males (70%). No deaths were reported. Combined, these data were useful for describing mushroom exposures. Most exposures occurred in males and in young children (≤6 years of age) and young adults (16-25 years of age), with 78% resulting in contact with a health-care facility. Education should target parents of young children-especially during summer, when mushrooms are more abundant-and young adults who are likely experimenting with mushrooms for their potential hallucinogenic properties.

Changing US Population Demographics: What Does This Mean for Listeriosis Incidence and Exposure?

PubMed Central

Pouillot, Régis; Van Doren, Jane M.

2017-01-01

Abstract Listeria monocytogenes is an important cause of foodborne illness hospitalization, fetal loss, and death in the United States. Listeriosis incidence rate varies significantly among population subgroups with pregnant women, older persons, and the Hispanic population having increased relative risks compared with the other subpopulations. Using estimated rates of listeriosis per subpopulation based on FoodNet data from 2004 to 2009, we evaluate the expected number of cases and incidence rates of listeriosis in the US population and the pregnant women subpopulation as the demographic composition changes over time with respect to ethnicity, pregnancy status, and age distribution. If the incidence rate per subpopulation is held constant, the overall US population listeriosis incidence rate would increase from 0.25 per 100,000 (95% confidence interval [CI]: 0.19–0.34) in 2010 to 0.28 (95% CI: 0.22–0.38) in 2020 and 0.32 (95% CI: 0.25–0.43) in 2030, because of the changes in the population structure. Similarly, the pregnancy-associated incidence rate is expected to increase from 4.0 per 100,000 pregnant women (95% CI: 2.5–6.5) in 2010 to 4.1 (95% CI: 2.6–6.7) in 2020 and 4.4 (95% CI: 2.7–7.2) in 2030 as the proportion of Hispanic pregnant women increases. We further estimate that a reduction of 12% in the exposure of the US population to L. monocytogenes would be needed to maintain a constant incidence rate from 2010 to 2020 (current trend), assuming infectivity (strain virulence distribution and individual susceptibility) is unchanged. To reduce the overall US population incidence rate by one-third (Healthy People 2020 goal) would require a reduction in exposure (or infectivity) to L. monocytogenes of 48% over the same time period. Reduction/elimination in exposure of pregnant and Hispanic subpopulations alone could not meet this target. This information may be useful in setting public health targets, developing risk management options, and in

An Atlas of ShakeMaps and population exposure catalog for earthquake loss modeling

USGS Publications Warehouse

Allen, T.I.; Wald, D.J.; Earle, P.S.; Marano, K.D.; Hotovec, A.J.; Lin, K.; Hearne, M.G.

2009-01-01

We present an Atlas of ShakeMaps and a catalog of human population exposures to moderate-to-strong ground shaking (EXPO-CAT) for recent historical earthquakes (1973-2007). The common purpose of the Atlas and exposure catalog is to calibrate earthquake loss models to be used in the US Geological Survey's Prompt Assessment of Global Earthquakes for Response (PAGER). The full ShakeMap Atlas currently comprises over 5,600 earthquakes from January 1973 through December 2007, with almost 500 of these maps constrained-to varying degrees-by instrumental ground motions, macroseismic intensity data, community internet intensity observations, and published earthquake rupture models. The catalog of human exposures is derived using current PAGER methodologies. Exposure to discrete levels of shaking intensity is obtained by correlating Atlas ShakeMaps with a global population database. Combining this population exposure dataset with historical earthquake loss data, such as PAGER-CAT, provides a useful resource for calibrating loss methodologies against a systematically-derived set of ShakeMap hazard outputs. We illustrate two example uses for EXPO-CAT; (1) simple objective ranking of country vulnerability to earthquakes, and; (2) the influence of time-of-day on earthquake mortality. In general, we observe that countries in similar geographic regions with similar construction practices tend to cluster spatially in terms of relative vulnerability. We also find little quantitative evidence to suggest that time-of-day is a significant factor in earthquake mortality. Moreover, earthquake mortality appears to be more systematically linked to the population exposed to severe ground shaking (Modified Mercalli Intensity VIII+). Finally, equipped with the full Atlas of ShakeMaps, we merge each of these maps and find the maximum estimated peak ground acceleration at any grid point in the world for the past 35 years. We subsequently compare this "composite ShakeMap" with existing global

Glyphosate in the general population and in applicators: a critical review of studies on exposures.

PubMed

Solomon, Keith R

2016-09-01

The recent classification of glyphosate as a probable human carcinogen by the International Agency for Research on Cancer (IARC) was arrived at without a detailed assessment of exposure. Glyphosate is widely used as an herbicide, which might result in exposures of the general public and applicators. Exposures were estimated from information in the open literature and unpublished reports provided by Monsanto Company. Based on the maximum measured concentration in air, an exposure dose of 1.04 × 10  -   6  mg/kg body mass (b.m.)/d was estimated. Assuming consumption of surface water without treatment, the 90th centile measured concentration would result in a consumed dose of 2.25 × 10  -   5  mg/kg b.m./d. Estimates by the Food and Agriculture Organization of the United Nations (FAO) of consumed doses in food provided a median exposure of 0.005 mg/kg b.m./d (range 0.002-0.013). Based on tolerance levels, the conservative estimate by the US Environmental Protection Agency (US EPA) for exposure of the general population via food and water was 0.088 mg/kg b.m./d (range 0.058-0.23). For applicators, 90th centiles for systemic exposures based on biomonitoring and dosimetry (normalized for penetration through the skin) were 0.0014 and 0.021 mg/kg b.m./d, respectively. All of these exposures are less than the reference dose and the acceptable daily intakes proposed by several regulatory agencies, thus supporting a conclusion that even for these highly exposed populations the exposures were within regulatory limits.

Bronchopulmonary C-fibers' IL1RI contributes to the prolonged apneic response to intra-atrial injection of capsaicin by prenatal nicotinic exposure in rat pups

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhao, Lei; Zhuang, Jianguo; Xu, Fadi, E-mail: fxu@

Prenatal nicotinic exposure (PNE) as a SIDS model reportedly sensitizes bronchopulmonary C-fibers (PCFs), contributing to the prolonged PCF-mediated apnea in rat pups, but the relevant mechanisms are not fully understood. Pulmonary IL-1β upregulated by cigarette smoke is known to stimulate or sensitize PCFs acting via IL-1 type I receptor (IL1RI) and inhibit inspiration frequency. Because of its upregulation observed in SIDS victims, we hypothesized that PNE increased pulmonary IL-1β release and IL1RI expression in pulmonary C-neurons via action on α7 nicotinic acetylcholine receptors (α7nAChR) to induce the prolonged PCF-mediated apnea. IL-1β in BALF and IL1RI in the nodose/jugular (N/J) ganglionmore » and vagal pulmonary C-neurons retrogradely-traced were compared between Ctrl (saline) and PNE pups and among the vehicle-treated Ctrl and PNE and methyllycaconitine (a selective α7nAChR antagonist)-treated PNE pups. The effect of IL-1RI blockade (IL-1Ra) on the PCF-mediated apnea was also compared between Ctrl and PNE pups. PNE significantly elevated IL-1β in BALF and upregulated IL1RI gene and protein expression in N/J ganglia and gene in vagal pulmonary C-neurons. All of these responses were eliminated by pretreatment with blockade of α7nAChR. In addition, the prolonged PCF-mediated apnea in PNE pups was significantly shortened by right atrial bolus injection of IL-1Ra. We conclude that PNE enhances pulmonary IL-1β release and PCF IL1RI expression acting via α7nAChR in contributing to sensitization of PCFs and prolongation of the PCF-mediated apneic response. - Highlights: • PNE increased pulmonary IL-1β release and IL1R1 expression in the N/J ganglia. • PNE elevated IL1R1 mRNA in vagal pulmonary C-neurons. • Blockage of peripheral IL1R1 reduced the PNE-induced PCF sensitization. • PNE induced the changes in IL-1β and IL1R1 dependent on action of α7nAChR.« less

Prolonged environment-induced hyperthermia alters autophagy in oxidative skeletal muscle in Sus scrofa.

PubMed

Ganesan, Shanthi; Brownstein, Alexandra J; Pearce, Sarah C; Hudson, Matthew B; Gabler, Nicolas K; Baumgard, Lance H; Rhoads, Robert P; Selsby, Joshua T

2018-05-01

Prolonged heat stress represents a continuing threat to human health and agricultural production. Despite the broad, negative impact of prolonged hyperthermia little is known about underlying pathological mechanisms leading to negative health outcomes, which has limited the development of etiological interventions and left clinicians and producers with only cooling and rehydration strategies. The purpose of this investigation was to determine the extent to which prolonged environment-induced hyperthermia altered autophagy in oxidative skeletal muscle in a large animal model, serving the dual purpose of accurately modeling human physiology as well as agricultural production. We hypothesized that prolonged hyperthermia would induce autophagy in skeletal muscle, independent of the accompanying caloric restriction. To test this hypothesis pigs were treated as follows: thermoneutral (20 °C), heat stress (35 °C), or were held under thermoneutral conditions but pair-fed to the heat stress group for seven days. Upon euthanasia the red portion of the semitendinosus was collected. We found that prolonged hyperthermic exposure increased oxidative stress without a corresponding change in antioxidant enzyme activities. Hyperthermia prevented initiation of autophagy despite increased markers of nucleation, elongation and autophagosome formation. However, p62 relative protein abundance, which is inversely correlated with autophagic degradation, was strongly increased suggesting suppressed degradation of autophagosomes. Markers of mitophagy and mitochondrial abundance were largely similar between groups. These data indicate that faulty autophagy plays a key role in hyperthermic muscle dysfunction. Copyright © 2018 Elsevier Ltd. All rights reserved.

Risk assessment of population inhalation exposure to volatile organic compounds and carbonyls in urban China.

PubMed

Du, Zhengjian; Mo, Jinhan; Zhang, Yinping

2014-12-01

Over the past three decades, China has experienced rapid urbanization. The risks to its urban population posed by inhalation exposure to hazardous air pollutants (HAPs) have not been well characterized. Here, we summarize recent measurements of 16 highly prevalent HAPs in urban China and compile their distribution inputs. Based on activity patterns of urban Chinese working adults, we derive personal exposures. Using a probabilistic risk assessment method, we determine cancer and non-cancer risks for working females and males. We also assess the uncertainty associated with risk estimates using Monte Carlo simulation, accounting for variations in HAP concentrations, cancer potency factors (CPFs) and inhalation rates. Average total lifetime cancer risks attributable to HAPs are 2.27×10(-4) (2.27 additional cases per 10,000 people exposed) and 2.93×10(-4) for Chinese urban working females and males, respectively. Formaldehyde, 1,4-dichlorobenzene, benzene and 1,3-butadiene are the major risk contributors yielding the highest median cancer risk estimates, >1×10(-5). About 70% of the risk is due to exposures occurring in homes. Outdoor sources contribute most to the risk of benzene, ethylbenzene and carbon tetrachloride, while indoor sources dominate for all other compounds. Chronic exposure limits are not exceeded for non-carcinogenic effects, except for formaldehyde. Risks are overestimated if variation is not accounted for. Sensitivity analyses demonstrate that the major contributors to total variance are range of inhalation rates, CPFs of formaldehyde, 1,4-dichlorobenzene, benzene and 1,3-butadiene, and indoor home concentrations of formaldehyde and benzene. Despite uncertainty, risks exceeding the acceptable benchmark of 1×10(-6) suggest actions to reduce exposures. Future efforts should be directed toward large-scale measurements of air pollutant concentrations, refinement of CPFs and investigation of population exposure parameters. The present study is a first

Paternal work stress and prolonged time to pregnancy.

PubMed

Lee, Mi-Sun; Paek, Domyung; Eum, Ki-Do; Siegrist, Johannes; Li, Jian; Lee, Hye-Eun; Cho, Sung-Il

2009-01-01

The aim of this study was to explore an association between psychosocial stress at work in married men and their spouses' prolonged time to pregnancy (TTP). All married male workers of a large Korean petrochemical enterprise and their wives fulfilling the selection criteria were included. Main selection criteria were lack of use of contraceptives and experienced pregnancy in recent past. Data were available from 322 couples. Psychosocial stress at work was measured by the effort-reward imbalance questionnaire. Prolonged TTP was measured by the "TTP questionnaire". After adjustment for confounding effects of demographic and life-style characteristics and benzene exposure, delayed TTP, defined by frequency of first-cycle pregnancy, was associated with one standard deviation (SD) increase of the effort-reward ratio in the chronically stressed group of married men (OR = 0.47; 95% CI = 0.22-0.99) in logistic regression analysis. A similar, but somewhat weaker effect, was found for the overall group (OR = 0.67; 95% CI = 0.47-0.94). Paternal stress at work, as measured by effort-reward imbalance, seemed to be associated with a decreased number of conceptions in the first menstrual cycle.

Permethrin treated clothing to protect outdoor workers: evaluation of different methods for mosquito exposure against populations with differing resistance status.

PubMed

Richards, Stephanie L; Agada, Nwanne; Balanay, Jo Anne G; White, Avian V

2018-02-01

Minimizing arthropod exposure (e.g. mosquito and tick bites) is vital to protect health of outdoor workers. Personal protective measures can help protect against exposure. Here, the quantity of permethrin was evaluated for different fabric types after washing. Cone and petri dish exposure assays were used to investigate the knockdown/mortality of permethrin-susceptible and permethrin-resistant populations of mosquitoes. Permethrin-treated clothing was effective against the tested mosquito population that was susceptible to permethrin but not a permethrin-resistant population. Permethrin quantity was significantly highest in the 100% cotton fabric and for the 0 wash group. Permethrin quantity in fabrics decreased with washing. No significant differences (p > 0.05) were observed in knockdown/mortality rates for either exposure method. The protective effect of permethrin-treated clothing against mosquitoes is impacted by many factors, e.g. wash frequency, fabric type, and the susceptibility/resistance status of local mosquito populations.

Recovery of Breathing and Forelimb Function after Prolonged Exposure to Repetitive Acute Intermittent Hypoxia

DTIC Science & Technology

2017-03-01

breathing capacity (Aim 1) and forelimb function (Aim 2), without systemic hypertension or hippocampal pathology (Aim 3). SPECIFIC AIMS Aim 1 (Florida...benefits. On the other hand, there was no evidence for pathology ( hypertension or hippocampal pathology). We were not able to perform time-series... hypertension or hippocampal (CA1) pathology. However, we did see striking (and surprising) preliminary evidence that prolonged rAIH: 1) reduced volume of the

Gene-environment interaction between SCN5A-1103Y and hypokalemia influences QT interval prolongation in African Americans: the Jackson Heart Study.

PubMed

Akylbekova, Ermeg L; Payne, John P; Newton-Cheh, Christopher; May, Warren L; Fox, Ervin R; Wilson, James G; Sarpong, Daniel F; Taylor, Herman A; Maher, Joseph F

2014-01-01

African-American ancestry, hypokalemia, and QT interval prolongation on the electrocardiogram are all risk factors for sudden cardiac death (SCD), but their interactions remain to be characterized. SCN5A-1103Y is a common missense variant, of African ancestry, of the cardiac sodium channel gene. SCN5A-1103Y is known to interact with QT-prolonging factors to promote ventricular arrhythmias in persons at high risk for SCD, but its clinical impact in the general African-American population has not been established. We genotyped SCN5A-S1103Y in 4,476 participants of the Jackson Heart Study, a population-based cohort of African Americans. We investigated the effect of SCN5A-1103Y, including interaction with hypokalemia, on QT interval prolongation, a widely-used indicator of prolonged myocardial repolarization and predisposition to SCD. We then evaluated the two sub-components of the QT interval: QRS duration and JT interval. The carrier frequency for SCN5A-1103Y was 15.4%. SCN5A-1103Y was associated with QT interval prolongation (2.7 milliseconds; P < .001) and potentiated the effect of hypokalemia on QT interval prolongation (14.6 milliseconds; P = .02). SCN5A-1103Y had opposing effects on the two sub-components of the QT interval, with shortening of QRS duration (-1.5 milliseconds; P = .001) and prolongation of the JT interval (3.4 milliseconds; P < .001). Hypokalemia was associated with diuretic use (78%; P < .001). SCN5A-1103Y potentiates the effect of hypokalemia on prolonging myocardial repolarization in the general African-American population. These findings have clinical implications for modification of QT prolonging factors, such as hypokalemia, in the 15% of African Americans who are carriers of SCN5A-1103Y. © 2014.

Translating QT interval prolongation from conscious dogs to humans.

PubMed

Dubois, Vincent F S; Smania, Giovanni; Yu, Huixin; Graf, Ramona; Chain, Anne S Y; Danhof, Meindert; Della Pasqua, Oscar

2017-02-01

In spite of screening procedures in early drug development, uncertainty remains about the propensity of new chemical entities (NCEs) to prolong the QT/QTc interval. The evaluation of proarrhythmic activity using a comprehensive in vitro proarrhythmia assay does not fully account for pharmacokinetic-pharmacodynamic (PKPD) differences in vivo. In the present study, we evaluated the correlation between drug-specific parameters describing QT interval prolongation in dogs and in humans. Using estimates of the drug-specific parameter, data on the slopes of the PKPD relationships of nine compounds with varying QT-prolonging effects (cisapride, sotalol, moxifloxacin, carabersat, GSK945237, SB237376 and GSK618334, and two anonymized NCEs) were analysed. Mean slope estimates varied between -0.98 ms μM -1 and 6.1 ms μM -1 in dogs and -10 ms μM -1 and 90 ms μM -1 in humans, indicating a wide range of effects on the QT interval. Linear regression techniques were then applied to characterize the correlation between the parameter estimates across species. For compounds without a mixed ion channel block, a correlation was observed between the drug-specific parameter in dogs and humans (y = -1.709 + 11.6x; R 2  = 0.989). These results show that per unit concentration, the drug effect on the QT interval in humans is 11.6-fold larger than in dogs. Together with information about the expected therapeutic exposure, the evidence of a correlation between the compound-specific parameter in dogs and in humans represents an opportunity for translating preclinical safety data before progression into the clinic. Whereas further investigation is required to establish the generalizability of our findings, this approach can be used with clinical trial simulations to predict the probability of QT prolongation in humans. © 2016 The British Pharmacological Society.

Identifying the translational gap in the evaluation of drug-induced QTc interval prolongation

PubMed Central

Chain, Anne SY; Dubois, Vincent FS; Danhof, Meindert; Sturkenboom, Miriam CJM; Della Pasqua, Oscar

2013-01-01

Aims Given the similarities in QTc response between dogs and humans, dogs are used in pre-clinical cardiovascular safety studies. The objective of our investigation was to characterize the PKPD relationships and identify translational gaps across species following the administration of three compounds known to cause QTc interval prolongation, namely cisapride, d, l-sotalol and moxifloxacin. Methods Pharmacokinetic and pharmacodynamic data from experiments in conscious dogs and clinical trials were included in this analysis. First, pharmacokinetic modelling and deconvolution methods were applied to derive drug concentrations at the time of each QT measurement. A Bayesian PKPD model was then used to describe QT prolongation, allowing discrimination of drug-specific effects from other physiological factors known to alter QT interval duration. A threshold of ≥10 ms was used to explore the probability of prolongation after drug administration. Results A linear relationship was found to best describe the pro-arrhythmic effects of cisapride, d,l-sotalol and moxifloxacin both in dogs and in humans. The drug-specific parameter (slope) in dogs was statistically significantly different from humans. Despite such differences, our results show that the probability of QTc prolongation ≥10 ms in dogs nears 100% for all three compounds at the therapeutic exposure range in humans. Conclusions Our findings indicate that the slope of PKPD relationship in conscious dogs may be used as the basis for the prediction of drug-induced QTc prolongation in humans. Furthermore, the risk of QTc prolongation can be expressed in terms of the probability associated with an increase ≥10 ms, allowing direct inferences about the clinical relevance of the pro-arrhythmic potential of a molecule. PMID:23351036

Metal induced inhalation exposure in urban population: A probabilistic approach

NASA Astrophysics Data System (ADS)

Widziewicz, Kamila; Loska, Krzysztof

2016-03-01

The paper was aimed at assessing the health risk in the populations of three Silesian cities: Bielsko-Biała, Częstochowa and Katowice exposed to the inhalation intake of cadmium, nickel and arsenic present in airborne particulate matter. In order to establish how the exposure parameters affects risk a probabilistic risk assessment framework was used. The risk model was based on the results of the annual measurements of As, Cd and Ni concentrations in PM2.5 and the sets of data on the concentrations of those elements in PM10 collected by the Voivodship Inspectorate of Environmental Protection over 2012-2013 period. The risk was calculated as an incremental lifetime risk of cancer (ILCR) in particular age groups (infants, children, adults) following Monte Carlo approach. With the aim of depicting the effect the variability of exposure parameters exerts on the risk, the initial parameters of the risk model: metals concentrations, its infiltration into indoor environment, exposure duration, exposure frequency, lung deposition efficiency, daily lung ventilation and body weight were modeled as random variables. The distribution of inhalation cancer risk due to exposure to ambient metals concentrations was LN (1.80 × 10-6 ± 2.89 × 10-6) and LN (6.17 × 10-7 ± 1.08 × 10-6) for PM2.5 and PM10-bound metals respectively and did not exceed the permissible limit of the acceptable risk. The highest probability of contracting cancer was observed for Katowice residents exposed to PM2.5 - LN (2.01 × 10-6 ± 3.24 × 10-6). Across the tested age groups adults were approximately one order of magnitude at higher risk compared to infants. Sensitivity analysis showed that exposure duration (ED) and body weight (BW) were the two variables, which contributed the most to the ILCR.

ASSESSING EXPOSURES TO MOBILE SOURCE AIR TOXIC EMISSIONS FOR POPULATIONS LIVING NEAR ROADWAYS

EPA Science Inventory

A growing number of epidemiological studies have identified an increase in occurrence of adverse health effects for populations living near major roads. However, the biological mechanism(s) leading to the adverse effects have not been identified. Limitations in exposure assessm...

Methadone prolongs cardiac conduction in young patients with cancer-related pain

PubMed Central

Anghelescu, Doralina L.; Patel, Rakesh M.; Mahoney, Daniel P.; Trujillo, Luis; Faughnan, Lane G.; Steen, Brenda D.; Baker, Justin N.; Pei, Deqing

2016-01-01

Objective Methadone prolongs cardiac conduction, from mild corrected QT (QTc) prolongation to torsades de pointes and ventricular fibrillation, in adults. However, methadone use for pain and its effects on cardiac conduction have not been investigated in pediatric populations. Methods A retrospective review of QTc intervals in patients receiving methadone analgesia was conducted. Medical records from a 4-year period (September 2006 to October 2010) at a pediatric oncology institution were reviewed, and correlations were tested between cardiac conduction and methadone dosage and duration of therapy, electrolyte levels, renal and hepatic dysfunction, and concurrent medications. Results Of the 61 patients who received methadone, 37 met our inclusion criteria and underwent 137 electrocardiograms (ECGs). During methadone treatment, the mean QTc was longer than that at baseline (446.5 vs 437.55 ms). The mean methadone dose was 27.0 ± 24.3 mg/d (range, 5–125 mg/d; median, 20 mg/d) or 0.47 ± 0.45 mg/kg per day (range, 0.05–2.25 mg/kg per day; median, 0.37 mg/kg per day), and the mean duration of therapy was 49 days. The authors identified a correlation between automated and manual ECG readings by two cardiologists (Pearson r = 0.649; p < 0.0001), but the authors found no correlations between methadone dose or duration and concurrent QTc-prolonging medications, sex, age, electrolyte abnormalities, or renal or hepatic dysfunction. Conclusion At a clinically effective analgesic dose, methadone dosage and duration were not correlated with QTc prolongation, even in the presence of other risk factors, suggesting that methadone use may be safe in pediatric populations. The correlation between automated and manual ECG readings suggests that automated ECG readings are reliable for monitoring cardiac conductivity during the reported methadone-dosage regimens. PMID:27194198

Lead exposure of the child population in Greece.

PubMed

Maravelias, C; Athanaselis, S; Poulos, L; Alevisopoulos, G; Ewers, U; Koutselinis, A

1994-12-18

Lead exposure of the child population was studied in three different areas in Greece: Kalamata which is a rural area of Southern Greece; Tavros, a district of Athens with a considerable industrial activity; and Lavrion, a small city near Athens where a lead-zinc mining and smelting industrial complex has existed for more than 90 years. The results were evaluated with respect to a number of individual, social and environmental variables (i.e. smelter, occupation of the father) especially those concerning the area of Lavrion which is the most heavily polluted area in Greece. The results of this study can be considered as an index for the extent of the lead pollution problem in the named areas of Greece.

Estimating population food and nutrient exposure: a comparison of store survey data with household panel food purchases.

PubMed

Eyles, Helen; Neal, Bruce; Jiang, Yannan; Ni Mhurchu, Cliona

2016-05-28

Population exposure to food and nutrients can be estimated from household food purchases, but store surveys of foods and their composition are more available, less costly and might provide similar information. Our aim was to compare estimates of nutrient exposure from a store survey of packaged food with those from household panel food purchases. A cross-sectional store survey of all packaged foods for sale in two major supermarkets was undertaken in Auckland, New Zealand, between February and May 2012. Longitudinal household food purchase data (November 2011 to October 2012) were obtained from the nationally representative, population-weighted New Zealand Nielsen HomeScan® panel. Data on 8440 packaged food and non-alcoholic beverage products were collected in the store survey. Food purchase data were available for 1229 households and 16 812 products. Store survey data alone produced higher estimates of exposure to Na and sugar compared with estimates from household panel food purchases. The estimated mean difference in exposure to Na was 94 (95 % CI 72, 115) mg/100 g (20 % relative difference; P<0·01), to sugar 1·6 (95 % CI 0·8, 2·5) g/100 g (11 %; P<0·01), to SFA -0·3 (95 % CI -0·8, 0·3) g/100 g (6 %; P=0·3) and to energy -18 (-71, 35) kJ/100 g (2 %; P=0·51). Compared with household panel food purchases, store survey data provided a reasonable estimate of average population exposure to key nutrients from packaged foods. However, caution should be exercised in using such data to estimate population exposure to Na and sugar and in generalising these findings to other countries, as well as over time.

Distinct effects of brief and prolonged adaptation on orientation tuning in primary visual cortex

PubMed Central

Patterson, Carlyn A.; Wissig, Stephanie C.; Kohn, Adam

2013-01-01

Recent stimulus history–adaptation–alters neuronal responses and perception. Previous electrophysiological and perceptual studies suggest that prolonged adaptation strengthens and makes more persistent the effects seen after briefer exposures. However, no systematic comparison has been made between the effects of adaptation lasting hundreds of milliseconds, which might arise during a single fixation, and the more prolonged adaptation typically used in imaging and perceptual studies. Here we determine how 0.4 s, 4 s, and 40 s of adaptation alters orientation tuning in primary visual cortex of anesthetized macaque monkeys, and how quickly responses recover after adapter offset. We measured responses to small (1.3 deg) and large (7.4 deg) gratings because previous work has shown that adaptation effects can depend on stimulus size. Adaptation with small gratings reduced responsivity and caused tuning to shift away from the adapter. These effects strengthened with more prolonged adaptation. For responses to large gratings, brief and prolonged adaptation produced indistinguishable effects on responsivity but caused opposite shifts in tuning preference. Recovery from adaptation was notably slower after prolonged adaptation, even when this did not induce stronger effects. We show that our results can be explained by an adaptation-induced weakening of surround suppression, the dynamics of this suppression, and differential effects of brief and prolonged adaptation across response epochs. Our findings show that effects do not simply scale with adaptation duration, and suggest that distinct strategies exist for adjusting to moment-to-moment fluctuations in input and to more persistent visual stimuli. PMID:23303933

Prenatal Arsenic Exposure and Birth Outcomes among a Population Residing near a Mining-Related Superfund Site.

PubMed

Claus Henn, Birgit; Ettinger, Adrienne S; Hopkins, Marianne R; Jim, Rebecca; Amarasiriwardena, Chitra; Christiani, David C; Coull, Brent A; Bellinger, David C; Wright, Robert O

2016-08-01

Limited epidemiologic data exist on prenatal arsenic exposure and fetal growth, particularly in the context of co-exposure to other toxic metals. We examined whether prenatal arsenic exposure predicts birth outcomes among a rural U.S. population, while adjusting for exposure to lead and manganese. We collected maternal and umbilical cord blood samples at delivery from 622 mother-infant pairs residing near a mining-related Superfund site in Northeast Oklahoma. Whole blood arsenic, lead, and manganese were measured using inductively coupled plasma mass spectrometry. We modeled associations between arsenic concentrations and birth weight, gestational age, head circumference, and birth weight for gestational age. Median (25th-75th percentile) maternal and umbilical cord blood metal concentrations, respectively, were as follows: arsenic, 1.4 (1.0-2.3) and 2.4 (1.8-3.3) μg/L; lead, 0.6 (0.4-0.9) and 0.4 (0.3-0.6) μg/dL; manganese, 22.7 (18.8-29.3) and 41.7 (32.2-50.4) μg/L. We estimated negative associations between maternal blood arsenic concentrations and birth outcomes. In multivariable regression models adjusted for lead and manganese, an interquartile range increase in maternal blood arsenic was associated with -77.5 g (95% CI: -127.8, -27.3) birth weight, -0.13 weeks (95% CI: -0.27, 0.01) gestation, -0.22 cm (95% CI: -0.42, -0.03) head circumference, and -0.14 (95% CI: -0.24, -0.04) birth weight for gestational age z-score units. Interactions between arsenic concentrations and lead or manganese were not statistically significant. In a population with environmental exposure levels similar to the U.S. general population, maternal blood arsenic was negatively associated with fetal growth. Given the potential for relatively common fetal and early childhood arsenic exposures, our finding that prenatal arsenic can adversely affect birth outcomes is of considerable public health importance. Claus Henn B, Ettinger AS, Hopkins MR, Jim R, Amarasiriwardena C, Christiani DC

Dietary cadmium exposure and kidney stone incidence: a population-based prospective cohort study of men & women.

PubMed

Thomas, Laura D K; Elinder, Carl-Gustaf; Tiselius, Hans-Göran; Wolk, Alicja; Akesson, Agneta

2013-09-01

Cadmium exposure is associated with increased urinary calcium excretion. Hypercalciuria is recognised as a major risk factor for kidney stone formation. Increased prevalence of kidney stones among those occupationally exposed to cadmium has previously been suggested. Food is the main source of cadmium exposure in the general population with tobacco representing an important additional source among smokers. We aimed to assess the association between dietary cadmium exposure and kidney stone incidence in two large population-based, prospective cohorts of men (Cohort of Swedish Men; COSM) and women (The Swedish Mammography Cohort; SMC). Those with a history of kidney stones were excluded. At baseline 1997, men (45-79yrs) and women (48 to 83yrs), completed a self-administered questionnaire on diet and lifestyle. During 12years of follow-up, we ascertained 707 cases of kidney stones in men and 290 in women through linkage of the cohorts to the national inpatient and outpatient registers. Individual dietary cadmium exposure was estimated using dietary data and concentrations of cadmium in food. Hazard ratios (HR) were calculated using the Cox proportional hazards regression models with adjustment for other risk factors. Estimated dietary cadmium exposure was not associated with increased kidney stone incidence among men HR 0.97 (95% confidence interval (CI): 0.77-1.23) or women HR 0.99 (95% CI: 0.89-1.43), comparing the highest tertile with the lowest. In conclusion, our results do not support a strong association between dietary cadmium and kidney stone risk at the exposure levels seen in the general population. Copyright © 2013 Elsevier Ltd. All rights reserved.

Effect of Prolonged Exposure Therapy Delivered Over 2 Weeks vs 8 Weeks vs Present-Centered Therapy on PTSD Symptom Severity in Military Personnel: A Randomized Clinical Trial.

PubMed

Foa, Edna B; McLean, Carmen P; Zang, Yinyin; Rosenfield, David; Yadin, Elna; Yarvis, Jeffrey S; Mintz, Jim; Young-McCaughan, Stacey; Borah, Elisa V; Dondanville, Katherine A; Fina, Brooke A; Hall-Clark, Brittany N; Lichner, Tracey; Litz, Brett T; Roache, John; Wright, Edward C; Peterson, Alan L

2018-01-23

Effective and efficient treatment is needed for posttraumatic stress disorder (PTSD) in active duty military personnel. To examine the effects of massed prolonged exposure therapy (massed therapy), spaced prolonged exposure therapy (spaced therapy), present-centered therapy (PCT), and a minimal-contact control (MCC) on PTSD severity. Randomized clinical trial conducted at Fort Hood, Texas, from January 2011 through July 2016 and enrolling 370 military personnel with PTSD who had returned from Iraq, Afghanistan, or both. Final follow-up was July 11, 2016. Prolonged exposure therapy, cognitive behavioral therapy involving exposure to trauma memories/reminders, administered as massed therapy (n = 110; 10 sessions over 2 weeks) or spaced therapy (n = 109; 10 sessions over 8 weeks); PCT, a non-trauma-focused therapy involving identifying/discussing daily stressors (n = 107; 10 sessions over 8 weeks); or MCC, telephone calls from therapists (n = 40; once weekly for 4 weeks). Outcomes were assessed before and after treatment and at 2-week, 12-week, and 6-month follow-up. Primary outcome was interviewer-assessed PTSD symptom severity, measured by the PTSD Symptom Scale-Interview (PSS-I; range, 0-51; higher scores indicate greater PTSD severity; MCID, 3.18), used to assess efficacy of massed therapy at 2 weeks posttreatment vs MCC at week 4; noninferiority of massed therapy vs spaced therapy at 2 weeks and 12 weeks posttreatment (noninferiority margin, 50% [2.3 points on PSS-I, with 1-sided α = .05]); and efficacy of spaced therapy vs PCT at posttreatment. Among 370 randomized participants, data were analyzed for 366 (mean age, 32.7 [SD, 7.3] years; 44 women [12.0%]; mean baseline PSS-I score, 25.49 [6.36]), and 216 (59.0%) completed the study. At 2 weeks posttreatment, mean PSS-I score was 17.62 (mean decrease from baseline, 7.13) for massed therapy and 21.41 (mean decrease, 3.43) for MCC (difference in decrease, 3.70 [95% CI,0.72 to 6.68]; P = .02

A population-based exposure assessment methodology for carbon monoxide: Development of a carbon monoxide passive sampler and occupational dosimeter

DOE Office of Scientific and Technical Information (OSTI.GOV)

Apte, Michael G.

Two devices, an occupational carbon monoxide (CO) dosimeter (LOCD), and an indoor air quality (IAQ) passive sampler were developed for use in population-based CO exposure assessment studies. CO exposure is a serious public health problem in the U.S., causing both morbidity and mortality (lifetime mortality risk approximately 10{sup -4}). Sparse data from population-based CO exposure assessments indicate that approximately 10% of the U.S. population is exposed to CO above the national ambient air quality standard. No CO exposure measurement technology is presently available for affordable population-based CO exposure assessment studies. The LOCD and IAQ Passive Sampler were tested in themore » laboratory and field. The palladium-molybdenum based CO sensor was designed into a compact diffusion tube sampler that can be worn. Time-weighted-average (TWA) CO exposure of the device is quantified by a simple spectrophotometric measurement. The LOCD and IAQ Passive Sampler were tested over an exposure range of 40 to 700 ppm-hours and 200 to 4200 ppm-hours, respectively. Both devices were capable of measuring precisely (relative standard deviation <20%), with low bias (<10%). The LOCD was screened for interferences by temperature, humidity, and organic and inorganic gases. Temperature effects were small in the range of 10°C to 30°C. Humidity effects were low between 20% and 90% RH. Ethylene (200 ppm) caused a positive interference and nitric oxide (50 ppm) caused a negative response without the presence of CO but not with CO.« less

FURTHER REFINEMENTS AND TESTING OF APEX3.0: EPA'S POPULATION EXPOSURE MODEL FOR CRITERIA AND AIR TOXIC INHALATION

EPA Science Inventory

The Air Pollutants Exposure Model (APEX(3.0)) is a PC-based model that was derived from the probabilistic NAAQS Exposure Model for carbon monoxide (pNEM/CO). APEX will be one of the tools used to estimate human population exposure for criteria and air toxic pollutants as part ...

Fluoride exposure and indicators of thyroid functioning in the Canadian population: implications for community water fluoridation

PubMed Central

Barberio, Amanda M; Hosein, F Shaun; Quiñonez, Carlos; McLaren, Lindsay

2017-01-01

Background There are concerns that altered thyroid functioning could be the result of ingesting too much fluoride. Community water fluoridation (CWF) is an important source of fluoride exposure. Our objectives were to examine the association between fluoride exposure and (1) diagnosis of a thyroid condition and (2) indicators of thyroid functioning among a national population-based sample of Canadians. Methods We analysed data from Cycles 2 and 3 of the Canadian Health Measures Survey (CHMS). Logistic regression was used to assess associations between fluoride from urine and tap water samples and the diagnosis of a thyroid condition. Multinomial logistic regression was used to examine the relationship between fluoride exposure and thyroid-stimulating hormone (TSH) level (low/normal/high). Other available variables permitted additional exploratory analyses among the subset of participants for whom we could discern some fluoride exposure from drinking water and/or dental products. Results There was no evidence of a relationship between fluoride exposure (from urine and tap water) and the diagnosis of a thyroid condition. There was no statistically significant association between fluoride exposure and abnormal (low or high) TSH levels relative to normal TSH levels. Rerunning the models with the sample constrained to the subset of participants for whom we could discern some source(s) of fluoride exposure from drinking water and/or dental products revealed no significant associations. Conclusion These analyses suggest that, at the population level, fluoride exposure is not associated with impaired thyroid functioning in a time and place where multiple sources of fluoride exposure, including CWF, exist. PMID:28839078

Matrix Population Model for Estimating Effects from Time-Varying Aquatic Exposures: Technical Documentation

EPA Science Inventory

The Office of Pesticide Programs models daily aquatic pesticide exposure values for 30 years in its risk assessments. However, only a fraction of that information is typically used in these assessments. The population model employed herein is a deterministic, density-dependent pe...

Population and business exposure to twenty scenario earthquakes in the State of Washington

USGS Publications Warehouse

Wood, Nathan; Ratliff, Jamie

2011-01-01

This report documents the results of an initial analysis of population and business exposure to scenario earthquakes in Washington. This analysis was conducted to support the U.S. Geological Survey (USGS) Pacific Northwest Multi-Hazards Demonstration Project (MHDP) and an ongoing collaboration between the State of Washington Emergency Management Division (WEMD) and the USGS on earthquake hazards and vulnerability topics. This report was developed to help WEMD meet internal planning needs. A subsequent report will provide analysis to the community level. The objective of this project was to use scenario ground-motion hazard maps to estimate population and business exposure to twenty Washington earthquakes. In consultation with the USGS Earthquake Hazards Program and the Washington Division of Geology and Natural Resources, the twenty scenario earthquakes were selected by WEMD (fig. 1). Hazard maps were then produced by the USGS and placed in the USGS ShakeMap archive.

Variable population exposure and distributed travel speeds in least-cost tsunami evacuation modelling

NASA Astrophysics Data System (ADS)

Fraser, S. A.; Wood, N. J.; Johnston, D. M.; Leonard, G. S.; Greening, P. D.; Rossetto, T.

2014-06-01

Evacuation of the population from a tsunami hazard zone is vital to reduce life-loss due to inundation. Geospatial least-cost distance modelling provides one approach to assessing tsunami evacuation potential. Previous models have generally used two static exposure scenarios and fixed travel speeds to represent population movement. Some analyses have assumed immediate evacuation departure time or assumed a common departure time for all exposed population. In this paper, a method is proposed to incorporate time-variable exposure, distributed travel speeds, and uncertain evacuation departure time into an existing anisotropic least-cost path distance framework. The model is demonstrated for a case study of local-source tsunami evacuation in Napier City, Hawke's Bay, New Zealand. There is significant diurnal variation in pedestrian evacuation potential at the suburb-level, although the total number of people unable to evacuate is stable across all scenarios. Whilst some fixed travel speeds can approximate a distributed speed approach, others may overestimate evacuation potential. The impact of evacuation departure time is a significant contributor to total evacuation time. This method improves least-cost modelling of evacuation dynamics for evacuation planning, casualty modelling, and development of emergency response training scenarios.

Treatment initiation and dropout from prolonged exposure and cognitive processing therapy in a VA outpatient clinic.

PubMed

Kehle-Forbes, Shannon M; Meis, Laura A; Spoont, Michele R; Polusny, Melissa A

2016-01-01

Emerging data suggest that few veterans are initiating prolonged exposure (PE) and cognitive processing therapy (CPT) and dropout levels are high among those who do start the therapies. The goal of this study was to use a large sample of veterans seen in routine clinical care to 1) report the percent of eligible and referred veterans who (a) initiated PE/CPT, (b) dropped out of PE/CPT, (c) were early PE/CPT dropouts, 2) examine predictors of PE/CPT initiation, and 3) examine predictors of early and late PE/CPT dropout. We extracted data from the medical records of 427 veterans who were offered PE/CPT following an intake at a Veterans Health Administration (VHA) PTSD Clinical Team. Eighty-two percent (n = 351) of veterans initiated treatment by attending Session 1 of PE/CPT; among those veterans, 38.5% (n = 135) dropped out of treatment. About one quarter of veterans who dropped out were categorized as early dropouts (dropout before Session 3). No significant predictors of initiation were identified. Age was a significant predictor of treatment dropout; younger veterans were more likely to drop out of treatment than older veterans. Therapy type was also a significant predictor of dropout; veterans receiving PE were more likely to drop out late than veterans receiving CPT. Findings demonstrate that dropout from PE/CPT is a serious problem and highlight the need for additional research that can guide the development of interventions to improve PE/CPT engagement and adherence. (c) 2016 APA, all rights reserved).

Occupational exposures and asthma in 14,000 adults from the general population

PubMed Central

Le Moual, Nicole; Kennedy, Susan M.; Kauffmann, Francine

2004-01-01

The association of occupational exposures and asthma were studied in 14151 adults, aged 25–59 years, from the general population of the French PAARC (Pollution Atmospherique et Affections Respiratoires Chroniques, 1975) Survey. Associations of asthma to specific jobs such as personal care workers, waiters, stock clerks were observed, with age, sex, smoking adjusted odds ratios between 1.5 and 1.7. Exposures to 18 asthmagenic agents (low, high molecular weight and mixed environment) were estimated by an asthma-specific job exposure matrix. Risks associated with asthma increased when excluding subjects with imprecise estimates of exposure. Risks further increased when increasing specificity of the definition of asthma considering jobs or specific agents such as industrial cleaning agents, latex, flour, highly reactive chemicals, and textiles. For example, for industrial cleaning agents, odds ratios increased from 1.55 (95% CI: 1.08, 2.23) for ever asthma, to 2.51 (95% CI: 1.33, 4.75) for asthma with airflow limitation, to 2.17 (95% CI: 1.41, 3.34) for asthma onset after age 14, and to 2.35 (95% CI: 1.38, 4.00) for asthma onset after beginning of current job. Results underlined the importance of the specificity of exposure and asthma definitions and indicated a deleterious role of occupational exposure on asthma, especially for cleaning agents. PMID:15561990

Conservation of body calcium by increased dietary intake of potassium: A potential measure to reduce the osteoporosis process during prolonged exposure to microgravity

NASA Technical Reports Server (NTRS)

Nechay, Bohdan R.

1989-01-01

During the 1988 NASA Summer Faculty Fellowship Program, it was proposed that the loss of skeletal calcium upon prolonged exposure to microgravity could be explained, in part, by a renal maladjustment characterized by an increased urinary excretion of calcium. It was theorized that because the conservation of body fluids and electrolytes depends upon the energy of adenosine triphosphate and enzymes that control the use of its energy for renal ion transport, an induction of renal sodium and potassium-dependent adenosine triphosphatase (Na + K ATPase) by oral loading with potassium would increase the reabsorption of sodium directly and that of calcium indirectly, leading to improved hydration and to reduced calcium loss. Preliminary studies showed the following. Rats drinking water containing 0.2 M potassium chloride for six to 13 days excreted in urine 22 muEq of calcium and 135 muEq of sodium per 100 grams of body weight per day. The corresponding values for control rats drinking tap water were 43 muEq and 269 muEq respectively. Renal Na + K ATPase activity in potassium loaded rats was higher than in controls. Thus, oral potassium loading resulted in increased Na + K ATPase activity and diminished urinary excretion of calcium and of sodium as predicted by the hypothesis. An extension of these studies to humans has the potential of resulting in development of harmless, non-invasive, drug-free, convenient measures to reduce bone loss and other electrolyte and fluid problems in space travelers exposed to prolonged periods of microgravity.

Assessment of prescription opioid intentional exposures across the rural-urban continuum in the United States using both population and drug availability rates.

PubMed

Le Lait, Marie-Claire; Martinez, Erin M; Severtson, Stevan G; Lavery, Sarah A; Bucher-Bartelson, Becki; Dart, Richard C

2014-12-01

Prescription opioid abuse and misuse are a serious problem in the U.S. today. Several studies have shown that the epidemic disproportionately affects rural areas. This paper uses three different rates to gain a more complete picture of opioid abuse in rural areas. This study examines prescription opioid intentional exposures using opioid classes tracked in the RADARS(®) System Poison Center Program. Intentional exposure rates were calculated adjusting for population and unique recipients of dispensed drug (URDD). These rates were analyzed using time (quarter) and the proportion of a three-digit zip code residing in a rural area as covariates. Additionally, the URDD per population rate was calculated to examine the proportion of the population filling prescriptions for opioids. After adjusting for population, intentional exposure cases significantly increased as the proportion of the population residing in a rural area increased. However, when adjusting for URDD, intentional exposure cases decreased with increasing rural population. The URDD per population increased as the proportion of people residing in a rural area increased. Using both population and URDD adjusted intentional exposure rates gives a more complete picture of opioid abuse in rural areas. Considering product availability can be used to develop opioid abuse prevention strategies and further the education of physicians serving rural areas about this epidemic. Copyright © 2014 John Wiley & Sons, Ltd.

Analysis of Intervention Strategies for Inhalation Exposure to Polycyclic Aromatic Hydrocarbons and Associated Lung Cancer Risk Based on a Monte Carlo Population Exposure Assessment Model

PubMed Central

Zhou, Bin; Zhao, Bin

2014-01-01

It is difficult to evaluate and compare interventions for reducing exposure to air pollutants, including polycyclic aromatic hydrocarbons (PAHs), a widely found air pollutant in both indoor and outdoor air. This study presents the first application of the Monte Carlo population exposure assessment model to quantify the effects of different intervention strategies on inhalation exposure to PAHs and the associated lung cancer risk. The method was applied to the population in Beijing, China, in the year 2006. Several intervention strategies were designed and studied, including atmospheric cleaning, smoking prohibition indoors, use of clean fuel for cooking, enhancing ventilation while cooking and use of indoor cleaners. Their performances were quantified by population attributable fraction (PAF) and potential impact fraction (PIF) of lung cancer risk, and the changes in indoor PAH concentrations and annual inhalation doses were also calculated and compared. The results showed that atmospheric cleaning and use of indoor cleaners were the two most effective interventions. The sensitivity analysis showed that several input parameters had major influence on the modeled PAH inhalation exposure and the rankings of different interventions. The ranking was reasonably robust for the remaining majority of parameters. The method itself can be extended to other pollutants and in different places. It enables the quantitative comparison of different intervention strategies and would benefit intervention design and relevant policy making. PMID:24416436

Analysis of intervention strategies for inhalation exposure to polycyclic aromatic hydrocarbons and associated lung cancer risk based on a Monte Carlo population exposure assessment model.

PubMed

Zhou, Bin; Zhao, Bin

2014-01-01

It is difficult to evaluate and compare interventions for reducing exposure to air pollutants, including polycyclic aromatic hydrocarbons (PAHs), a widely found air pollutant in both indoor and outdoor air. This study presents the first application of the Monte Carlo population exposure assessment model to quantify the effects of different intervention strategies on inhalation exposure to PAHs and the associated lung cancer risk. The method was applied to the population in Beijing, China, in the year 2006. Several intervention strategies were designed and studied, including atmospheric cleaning, smoking prohibition indoors, use of clean fuel for cooking, enhancing ventilation while cooking and use of indoor cleaners. Their performances were quantified by population attributable fraction (PAF) and potential impact fraction (PIF) of lung cancer risk, and the changes in indoor PAH concentrations and annual inhalation doses were also calculated and compared. The results showed that atmospheric cleaning and use of indoor cleaners were the two most effective interventions. The sensitivity analysis showed that several input parameters had major influence on the modeled PAH inhalation exposure and the rankings of different interventions. The ranking was reasonably robust for the remaining majority of parameters. The method itself can be extended to other pollutants and in different places. It enables the quantitative comparison of different intervention strategies and would benefit intervention design and relevant policy making.

Physiology of prolonged bed rest

NASA Technical Reports Server (NTRS)

Greenleaf, J. E.

1988-01-01

Bed rest has been a normal procedure used by physicians for centuries in the treatment of injury and disease. Exposure of patients to prolonged bed rest in the horizontal position induces adaptive deconditioning responses. While deconditioning responses are appropriate for patients or test subjects in the horizontal position, they usually result in adverse physiological responses (fainting, muscular weakness) when the patient assume the upright posture. These deconditioning responses result from reduction in hydrostatic pressure within the cardiovascular system, virtual elimination of longitudinal pressure on the long bones, some decrease in total body metabolism, changes in diet, and perhaps psychological impact from the different environment. Almost every system in the body is affected. An early stimulus is the cephalic shift of fluid from the legs which increases atrial pressure and induces compensatory responses for fluid and electrolyte redistribution. Without countermeasures, deterioration in strength and muscle function occurs within 1 wk while increased calcium loss may continue for months. Research should also focus on drug and carbohydrate metabolism.

Previous Exposure to Anesthesia and Autism Spectrum Disorder (ASD): A Puerto Rican Population-Based Sibling Cohort Study.

PubMed

Creagh, O; Torres, H; Rivera, K; Morales-Franqui, M; Altieri-Acevedo, G; Warner, D

2016-01-01

Autism Spectrum Disorder (ASD) is characterized by impaired social interaction and communication, and by restricted and repetitive behavior, that begins usually before a child is three years old.(1) Researchers have shown that prevalence rates in the U.S. may be as high as 1 in 68.(52) A number of studies have examined the effects of early exposure to anesthesia on brain development and subsequent impairment in neurocognitive function; yet, little is known about the possible effects of anesthetic agents on social-behavioral functioning. The association between exposure to anesthesia either in uterus, during the first years of life, or later and development of Autistic Spectrum Disorder (ASD) or its severity was determined in a retrospective population based cohort study. Identify if children who had previous exposure to anesthesia either in uterus, first years of life during their developing brain years, or later, are at risk of developing ASD and its severe form of the disease. Data was obtained from structured interviews administered to a sample of 515 parents/guardians distributed in two groups: ASD = 262 children diagnosed with this condition and Non-ASD: 253 children (siblings of ASD group) without diagnosis (95% confidence interval) that freely decided to participate and agreed to a consent form. Variables studied include: demographics, diagnosis and severity of ASD, exposure to anesthesia, method of childbirth, and age of exposure Children less than 2 years of age were considered into have developing brain period. Data was analyzed using Chi-square or Fisher exact test. In contrast to non-ASD group, most of the children within ASD group were male, 76% (p=0.0001). With regards to methods of childbirth, 64% of the ASD population were vaginal delivery (VD; Non-anesthesia exposure group) and 36% cesarean delivery (CD) compared to non-autistic population with 71% VD and 29% CD, which demonstrates no statistical difference between both groups (p=0.1113). Out of

Previous Exposure to Anesthesia and Autism Spectrum Disorder (ASD): A Puerto Rican Population-Based Sibling Cohort Study.

PubMed

Creagh, O; Torres, H; Rivera, K; Morales-Franqui, M; Altieri-Acevedo, G; Warner, D

2015-01-01

Autism Spectrum Disorder (ASD) is characterized by impaired social interaction and communication, and by restricted and repetitive behavior, that begins usually before a child is three years old.1 Researchers have shown that prevalence rates in the U.S. may be as high as 1 in 68.52 A number of studies have examined the effects of early exposure to anesthesia on brain development and subsequent impairment in neurocognitive function; yet, little is known about the possible effects of anesthetic agents on social-behavioral functioning. The association between exposure to anesthesia either in uterus, during the first years of life, or later and development of Autistic Spectrum Disorder (ASD) or its severity was determined in a retrospective population based cohort study. Identify if children who had previous exposure to anesthesia either in uterus, first years of life during their developing brain years, or later, are at risk of developing ASD and its severe form of the disease. Data was obtained from structured interviews administered to a sample of 515 parents/guardians distributed in two groups: ASD = 262 children diagnosed with this condition and Non-ASD: 253 children (siblings of ASD group) without diagnosis (p = 0.8069) when comparing exposure to anesthesia in uterus to subsequent severe form of ASD. Of the 262 ASD patients, 99 had exposure to anesthetics before their diagnosis, while in Non-ASD population, 110 had exposure to anesthesia, demonstrating no statistically significant association between both groups (p = 0.2091). Out of 99 ASD patients exposed to anesthesia prior to their diagnosis, 72 were exposed before age 2. When compared to the 110 Non-ASD patients exposed to anesthesia, 86 had exposure during this developing brain period, which indicates no statistically significant association (p = 0.4207). In addition, most of the ASD children exposed to anesthesia during developing brain were diagnosed with mild degree of the disorder when compared to ASD

Biologically based modeling of multimedia, multipathway, multiroute population exposures to arsenic

PubMed Central

Georgopoulos, Panos G.; Wang, Sheng-Wei; Yang, Yu-Ching; Xue, Jianping; Zartarian, Valerie G.; Mccurdy, Thomas; Özkaynak, Halûk

2011-01-01

This article presents an integrated, biologically based, source-to-dose assessment framework for modeling multimedia/multipathway/multiroute exposures to arsenic. Case studies demonstrating this framework are presented for three US counties (Hunderton County, NJ; Pima County, AZ; and Franklin County, OH), representing substantially different conditions of exposure. The approach taken utilizes the Modeling ENvironment for TOtal Risk studies (MENTOR) in an implementation that incorporates and extends the approach pioneered by Stochastic Human Exposure and Dose Simulation (SHEDS), in conjunction with a number of available databases, including NATA, NHEXAS, CSFII, and CHAD, and extends modeling techniques that have been developed in recent years. Model results indicate that, in most cases, the food intake pathway is the dominant contributor to total exposure and dose to arsenic. Model predictions are evaluated qualitatively by comparing distributions of predicted total arsenic amounts in urine with those derived using biomarker measurements from the NHEXAS — Region V study: the population distributions of urinary total arsenic levels calculated through MENTOR and from the NHEXAS measurements are in general qualitative agreement. Observed differences are due to various factors, such as interindividual variation in arsenic metabolism in humans, that are not fully accounted for in the current model implementation but can be incorporated in the future, in the open framework of MENTOR. The present study demonstrates that integrated source-to-dose modeling for arsenic can not only provide estimates of the relative contributions of multipathway exposure routes to the total exposure estimates, but can also estimate internal target tissue doses for speciated organic and inorganic arsenic, which can eventually be used to improve evaluation of health risks associated with exposures to arsenic from multiple sources, routes, and pathways. PMID:18073786

Environmental risks for nontuberculous mycobacteria. Individual exposures and climatic factors in the cystic fibrosis population.

PubMed

Prevots, D Rebecca; Adjemian, Jennifer; Fernandez, Aisling G; Knowles, Michael R; Olivier, Kenneth N

2014-09-01

Persons with cystic fibrosis are at high risk of pulmonary nontuberculous mycobacterial infection, with a national prevalence estimated at 13%. The risk of nontuberculous mycobacteria associated with specific environmental exposures, and the correlation with climatic conditions in this population has not been described. To describe the association of pulmonary nontuberculous mycobacteria with individual exposures to water and soil aerosols, and the population associations of these infections with climatic factors. We conducted a nested case-control study within a cohort study of pulmonary nontuberculous mycobacteria prevalence at 21 geographically diverse national cystic fibrosis centers. Incident nontuberculous mycobacterial infection cases (at least one prior negative culture followed by one positive culture) were age- and sex-matched to culture-negative controls. Exposures to water and soil were assessed by administering a standardized questionnaire. Cohort prevalence at each of the 21 centers was correlated with climatic conditions in the same area through linear regression modeling. Overall, 48 cases and 85 control subjects were enrolled. Indoor swimming was associated with incident infection (adjusted odds ratio, 5.9, 95% confidence interval, 1.3-26.1), although only nine cases (19%) and five control subjects (6%) reported indoor swimming in the 4 months prior to infection. Exposure to showering and municipal water supply was common among both cases and control subjects: 77% of cases and 76% of control subjects reported showering at least daily. In linear regression, average annual atmospheric water vapor content was significantly predictive of center prevalence (P = 0.0019), with R(2) = 0.40. Atmospheric conditions explain more of the variation in disease prevalence than individual behaviors. The risk of specific exposures may vary by geographic region due to differences in conditions favoring mycobacterial growth and survival. However, because exposure to

Xenon Treatment Protects Against Cold Ischemia Associated Delayed Graft Function and Prolongs Graft Survival in Rats

PubMed Central

Zhao, H; Watts, H R; Chong, M; Huang, H; Tralau-Stewart, C; Maxwell, P H; Maze, M; George, A J T; Ma, D

2013-01-01

Prolonged hypothermic storage causes ischemia-reperfusion injury (IRI) in the renal graft, which is considered to contribute to the occurrence of the delayed graft function (DGF) and chronic graft failure. Strategies are required to protect the graft and to prolong renal graft survival. We demonstrated that xenon exposure to human proximal tubular cells (HK-2) led to activation of range of protective proteins. Xenon treatment prior to or after hypothermia–hypoxia challenge stabilized the HK-2 cellular structure, diminished cytoplasmic translocation of high-mobility group box (HMGB) 1 and suppressed NF-κB activation. In the syngeneic Lewis-to-Lewis rat model of kidney transplantation, xenon exposure to donors before graft retrieval or to recipients after engraftment decreased caspase-3 expression, localized HMGB-1 within nuclei and prevented TLR-4/NF-κB activation in tubular cells; serum pro-inflammatory cytokines IL-1β, IL-6 and TNF-α were reduced and renal function was preserved. Xenon treatment of graft donors or of recipients prolonged renal graft survival following IRI in both Lewis-to-Lewis isografts and Fischer-to-Lewis allografts. Xenon induced cell survival or graft functional recovery was abolished by HIF-1α siRNA. Our data suggest that xenon treatment attenuates DGF and enhances graft survival. This approach could be translated into clinical practice leading to a considerable improvement in long-term graft survival. PMID:23710625

Xenon treatment attenuates early renal allograft injury associated with prolonged hypothermic storage in rats.

PubMed

Zhao, Hailin; Yoshida, Akira; Xiao, Wei; Ologunde, Rele; O'Dea, Kieran P; Takata, Masao; Tralau-Stewart, Catherine; George, Andrew J T; Ma, Daqing

2013-10-01

Prolonged hypothermic storage elicits severe ischemia-reperfusion injury (IRI) to renal grafts, contributing to delayed graft function (DGF) and episodes of acute immune rejection and shortened graft survival. Organoprotective strategies are therefore needed for improving long-term transplant outcome. The aim of this study is to investigate the renoprotective effect of xenon on early allograft injury associated with prolonged hypothermic storage. Xenon exposure enhanced the expression of heat-shock protein 70 (HSP-70) and heme oxygenase 1 (HO-1) and promoted cell survival after hypothermia-hypoxia insult in human proximal tubular (HK-2) cells, which was abolished by HSP-70 or HO-1 siRNA. In the brown Norway to Lewis rat renal transplantation, xenon administered to donor or recipient decreased the renal tubular cell death, inflammation, and MHC II expression, while delayed graft function (DGF) was therefore reduced. Pathological changes associated with acute rejection, including T-cell, macrophage, and fibroblast infiltration, were also decreased with xenon treatment. Donors or recipients treated with xenon in combination with cyclosporin A had prolonged renal allograft survival. Xenon protects allografts against delayed graft function, attenuates acute immune rejection, and enhances graft survival after prolonged hypothermic storage. Furthermore, xenon works additively with cyclosporin A to preserve post-transplant renal function.

Exploring physical exposures and identifying high-risk work tasks within the floor layer trade

PubMed Central

McGaha, Jamie; Miller, Kim; Descatha, Alexis; Welch, Laurie; Buchholz, Bryan; Evanoff, Bradley; Dale, Ann Marie

2014-01-01

Introduction Floor layers have high rates of musculoskeletal disorders yet few studies have examined their work exposures. This study used observational methods to describe physical exposures within floor laying tasks. Methods We analyzed 45 videos from 32 floor layers using Multimedia-Video Task Analysis software to determine the time in task, forces, postures, and repetitive hand movements for installation of four common flooring materials. We used the WISHA checklists to define exposure thresholds. Results Most workers (91%) met the caution threshold for one or more exposures. Workers showed high exposures in multiple body parts with variability in exposures across tasks and for different materials. Prolonged exposures were seen for kneeling, poor neck and low back postures, and intermittent but frequent hand grip forces. Conclusions Floor layers experience prolonged awkward postures and high force physical exposures in multiple body parts, which probably contribute to their high rates of musculoskeletal disorders. PMID:24274895

Antenatal exposure to Ureaplasma species exacerbates bronchopulmonary dysplasia synergistically with subsequent prolonged mechanical ventilation in preterm infants.

PubMed

Inatomi, Tadashi; Oue, Shinya; Ogihara, Tohru; Hira, Seigo; Hasegawa, Masashi; Yamaoka, Shigeo; Yasui, Masako; Tamai, Hiroshi

2012-03-01

The presence of microorganisms in gastric fluid in neonates at birth is postulated to reflect antenatal infection and also to be associated with the development of bronchopulmonary dysplasia (BPD). A logistic regression analysis, after controlling for other risk factors, indicated that Ureaplasma-positive infants were not at increased risk for moderate/severe BPD (adjusted odds ratio (OR): 2.58, 95% confidence interval (CI): 0.57-6.89, P = 0.12). However, the association between the presence of Ureaplasma species and the risk for moderate/severe BPD increased significantly in infants on mechanical ventilation (MV) ≥2 wk (adjusted OR: 4.17, 95% CI: 1.62-44.1, P = 0.009). An analysis using a lung injury marker indicated that Ureaplasma-positive infants with MV ≥2 wk, but not other infants, showed higher serum KL-6 levels in samples taken from cord blood, and that KL-6 levels increased time-dependently up to 4 wk of age. Antenatal exposure to Ureaplasma species induces lung injury prior to birth and synergistically contributes to the development of BPD in infants requiring prolonged MV (≥2 wk). We recovered gastric fluid specimens from 122 infants with gestational age (GA) <29 wk or birth weight <1,000 g to investigate whether these microorganisms influence respiratory outcome of BPD. A PCR analysis was used to detect urease and 16S ribosomal RNA (rRNA) genes to classify neonates into Ureaplasma-positive or Ureaplasma-negative infants.

Characteristics of U.S. veterans who begin and complete prolonged exposure and cognitive processing therapy for PTSD.

PubMed

Mott, Juliette M; Mondragon, Sasha; Hundt, Natalie E; Beason-Smith, Melissa; Grady, Rebecca H; Teng, Ellen J

2014-06-01

This retrospective chart-review study examined patient-level correlates of initiation and completion of evidence-based psychotherapy (EBP) for posttraumatic stress disorder (PTSD) among treatment-seeking U.S. veterans. We identified all patients (N = 796) in a large Veterans Affairs PTSD and anxiety clinic who attended at least 1 individual psychotherapy appointment with 1 of 8 providers trained in EBP. Within this group, 91 patients (11.4%) began EBP (either Cognitive Processing Therapy or Prolonged Exposure) and 59 patients (7.9%) completed EBP. The medical records of all EBP patients (n = 91) and a provider-matched sample of patients who received another form of individual psychotherapy (n = 66) were reviewed by 4 independent raters. Logistic regression analyses revealed that Iraq and Afghanistan veterans were less likely to begin EBP than veterans from other service eras, OR = 0.48, 95% CI = [0.24, 0.94], and veterans who were service connected for PTSD were more likely than veterans without service connection to begin EBP, OR = 2.33, 95% CI = [1.09, 5.03]. Among those who began EBP, Iraq and Afghanistan veteran status, OR = 0.09, 95% CI = [0.03, 0.30], and a history of psychiatric inpatient hospitalization, OR = 0.13, 95% CI = [0.03, 0.54], were associated with decreased likelihood of EBP completion. Published 2014. This article is a US Government work and is in the public domain in the USA.

Assessment of mycotoxin exposure in the Belgian population using biomarkers: aim, design and methods of the BIOMYCO study.

PubMed

Heyndrickx, Ellen; Sioen, Isabelle; Bellemans, Mia; De Maeyer, Mieke; Callebaut, Alfons; De Henauw, Stefaan; De Saeger, Sarah

2014-01-01

Mycotoxins are harmful food contaminants. Currently, human exposure assessment to these toxins is often based on calculations combining mycotoxin occurrence data in food with population data on food consumption. Because of limitations inherent to that approach, biomarkers have been proposed as a suitable alternative whereby a more accurate assessment of exposure at the individual level can be performed. The BIOMYCO study is designed to assess human mycotoxin exposure using urinary biomarkers of exposure. Over the different seasons of 2013 and 2014, morning urine is gathered in a representative part of the Belgian population according to a designed study protocol, whereby 140 children (3-12 years old) and 278 adults (19-65 years old) are selected based on random cluster sampling stratified for sex, age and geographical areas. Every participant completes a food frequency questionnaire to assess the consumption of relevant foodstuffs (n = 43) of both the day before the urine collection and the previous month. Validated multi-toxin LC-MS/MS methods are used to analyse aflatoxins, fumonisins, ochratoxin A, trichothecenes, zearalenone and their metabolites in morning urine. The study protocol is approved by the ethical committee of the Ghent University Hospital. Within this paper, study design and methods are described. The BIOMYCO study is the first study whereby a multi-toxin approach is applied for mycotoxin exposure assessment in adults and children on a large scale. Moreover, it is the first study that will describe the exposure to an elaborated set of mycotoxins in the Belgian population. In first instance, descriptive analysis will be performed, describing the exposure to mycotoxins for the child and adult group. Exposure of different subgroups will be compared. Furthermore, correlations between the mycotoxin concentrations measured and the food consumption reported will be estimated to explore whether the mycotoxin exposure could be explained by the consumption

A comparison of methods for calculating population exposure estimates of daily weather for health research.

PubMed

Hanigan, Ivan; Hall, Gillian; Dear, Keith B G

2006-09-13

To explain the possible effects of exposure to weather conditions on population health outcomes, weather data need to be calculated at a level in space and time that is appropriate for the health data. There are various ways of estimating exposure values from raw data collected at weather stations but the rationale for using one technique rather than another; the significance of the difference in the values obtained; and the effect these have on a research question are factors often not explicitly considered. In this study we compare different techniques for allocating weather data observations to small geographical areas and different options for weighting averages of these observations when calculating estimates of daily precipitation and temperature for Australian Postal Areas. Options that weight observations based on distance from population centroids and population size are more computationally intensive but give estimates that conceptually are more closely related to the experience of the population. Options based on values derived from sites internal to postal areas, or from nearest neighbour sites--that is, using proximity polygons around weather stations intersected with postal areas--tended to include fewer stations' observations in their estimates, and missing values were common. Options based on observations from stations within 50 kilometres radius of centroids and weighting of data by distance from centroids gave more complete estimates. Using the geographic centroid of the postal area gave estimates that differed slightly from the population weighted centroids and the population weighted average of sub-unit estimates. To calculate daily weather exposure values for analysis of health outcome data for small areas, the use of data from weather stations internal to the area only, or from neighbouring weather stations (allocated by the use of proximity polygons), is too limited. The most appropriate method conceptually is the use of weather data from

Nutritional considerations during prolonged exposure to a confined, hyperbaric, hyperoxic environment: recommendations for saturation divers.

PubMed

Deb, S K; Swinton, P A; Dolan, E

2016-01-01

Saturation diving is an occupation that involves prolonged exposure to a confined, hyperoxic, hyperbaric environment. The unique and extreme environment is thought to result in disruption to physiological and metabolic homeostasis, which may impact human health and performance. Appropriate nutritional intake has the potential to alleviate and/or support many of these physiological and metabolic concerns, whilst enhancing health and performance in saturation divers. Therefore, the purpose of this review is to identify the physiological and practical challenges of saturation diving and consequently provide evidence-based nutritional recommendations for saturation divers to promote health and performance within this challenging environment. Saturation diving has a high-energy demand, with an energy intake of between 44 and 52 kcal/kg body mass per day recommended, dependent on intensity and duration of underwater activity. The macronutrient composition of dietary intake is in accordance with the current Institute of Medicine guidelines at 45-65 % and 20-35 % of total energy intake for carbohydrate and fat intake, respectively. A minimum daily protein intake of 1.3 g/kg body mass is recommended to facilitate body composition maintenance. Macronutrient intake between individuals should, however, be dictated by personal preference to support the attainment of an energy balance. A varied diet high in fruit and vegetables is highly recommended for the provision of sufficient micronutrients to support physiological processes, such as vitamin B12 and folate intake to facilitate red blood cell production. Antioxidants, such as vitamin C and E, are also recommended to reduce oxidised molecules, e.g. free radicals, whilst selenium and zinc intake may be beneficial to reinforce endogenous antioxidant reserves. In addition, tailored hydration and carbohydrate fueling strategies for underwater work are also advised.

Exposure to ambient air pollution and the incidence of dementia: A population-based cohort study.

PubMed

Chen, Hong; Kwong, Jeffrey C; Copes, Ray; Hystad, Perry; van Donkelaar, Aaron; Tu, Karen; Brook, Jeffrey R; Goldberg, Mark S; Martin, Randall V; Murray, Brian J; Wilton, Andrew S; Kopp, Alexander; Burnett, Richard T

2017-11-01

Emerging studies have implicated air pollution in the neurodegenerative processes. Less is known about the influence of air pollution, especially at the relatively low levels, on developing dementia. We conducted a population-based cohort study in Ontario, Canada, where the concentrations of pollutants are among the lowest in the world, to assess whether air pollution exposure is associated with incident dementia. The study population comprised all Ontario residents who, on 1 April 2001, were 55-85years old, Canadian-born, and free of physician-diagnosed dementia (~2.1 million individuals). Follow-up extended until 2013. We used population-based health administrative databases with a validated algorithm to ascertain incident diagnosis of dementia as well as prevalent cases. Using satellite observations, land-use regression model, and an optimal interpolation method, we derived long-term average exposure to fine particulate matter (≤2.5μm in diameter) (PM 2.5 ), nitrogen dioxide (NO 2 ), and ozone (O 3 ), respectively at the subjects' historical residences based on a population-based registry. We used multilevel spatial random-effects Cox proportional hazards models, adjusting for individual and contextual factors, such as diabetes, brain injury, and neighborhood income. We conducted various sensitivity analyses, such as lagging exposure up to 10years and considering a negative control outcome for which no (or weaker) association with air pollution is expected. We identified 257,816 incident cases of dementia in 2001-2013. We found a positive association between PM 2.5 and dementia incidence, with a hazard ratio (HR) of 1.04 (95% confidence interval (CI): 1.03-1.05) for every interquartile-range increase in exposure to PM 2.5 . Similarly, NO 2 was associated with increased incidence of dementia (HR=1.10; 95% CI: 1.08-1.12). No association was found for O 3 . These associations were robust to all sensitivity analyses examined. These estimates translate to 6.1% of

Effects of prolonged exposure to moderate static magnetic field and its synergistic effects with alkaline pH on Enterococcus faecalis.

PubMed

Fan, Wei; Huang, Zhuo; Fan, Bing

2018-02-01

Static magnetic field (SMF) has been shown to biologically affect various microorganisms, but its effects on Enterococcus faecalis, which is associated with multiple dental infections, have not been reported yet. Besides, Enterococcus faecalis was found to be resistant to the alkaline environment provided by a major dental antimicrobial, calcium hydroxide. Therefore, the antibacterial activity of prolonged exposure to moderate SMF (170 mT) and its possible synergistic activity with alkaline pH (pH = 9) were evaluated in the study. The ability to form a biofilm under these conditions was examined by crystal violet assay. Real-time quantitative PCR was performed to evaluate the relative expression of stress (dnaK and groEL) and virulence (efaA, ace, gelE and fsrC) related genes. As the results indicated, cell proliferation was inhibited after 120 h of SMF exposure. What's more, the combined treatment of SMF and alkaline pH showed significantly improved antimicrobial action when compared to single SMF and alkaline pH treatment for more than 24 h and 72 h respectively. However, the ability to form a biofilm was also enhanced under SMF and alkaline pH treatments. SMF can induce stress response by up-regulating the expression of dnaK and elevate virulence gene expression (efaA and ace). These responses were more significant and more genes were up-regulated including groEL, gelE and fsrC when exposed to SMF and alkaline pH simultaneously. Hence, combination of SMF and alkaline pH could be a promising disinfection strategy in dental area and other areas associated with Enterococcus faecalis infections. Copyright © 2017 Elsevier Ltd. All rights reserved.

Variation in Definition of Prolonged Mechanical Ventilation.

PubMed

Rose, Louise; McGinlay, Michael; Amin, Reshma; Burns, Karen Ea; Connolly, Bronwen; Hart, Nicholas; Jouvet, Philippe; Katz, Sherri; Leasa, David; Mawdsley, Cathy; McAuley, Danny F; Schultz, Marcus J; Blackwood, Bronagh

2017-10-01

Consistency of definitional criteria for terminology applied to describe subject cohorts receiving mechanical ventilation within ICU and post-acute care settings is important for understanding prevalence, risk stratification, effectiveness of interventions, and projections for resource allocation. Our objective was to quantify the application and definition of terms for prolonged mechanical ventilation. We conducted a scoping review of studies (all designs except single-case study) reporting a study population (adult and pediatric) using the term prolonged mechanical ventilation or a synonym. We screened 5,331 references, reviewed 539 full-text references, and excluded 120. Of the 419 studies (representing 38 countries) meeting inclusion criteria, 297 (71%) reported data on a heterogeneous subject cohort, and 66 (16%) included surgical subjects only (46 of those 66, 70% cardiac surgery). Other studies described COPD (16, 4%), trauma (22, 5%), neuromuscular (17, 4%), and sepsis (1, 0.2%) cohorts. A total of 741 terms were used to refer to the 419 study cohorts. The most common terms were: prolonged mechanical ventilation (253, 60%), admission to specialized unit (107, 26%), and long-term mechanical ventilation (79, 19%). Some authors (282, 67%) defined their cohorts based on duration of mechanical ventilation, with 154 studies (55%) using this as the sole criterion. We identified 37 different durations of ventilation ranging from 5 h to 1 y, with > 21 d being the most common (28 of 282, 7%). For studies describing a surgical cohort, minimum ventilation duration required for inclusion was ≥ 24 h for 20 of 66 studies (30%). More than half of all studies (237, 57%) did not provide a reason/rationale for definitional criteria used, with only 28 studies (7%) referring to a consensus definition. We conclude that substantial variation exists in the terminology and definitional criteria for cohorts of subjects receiving prolonged mechanical ventilation. Standardization of

[Prolonged exposure to atmospheric air pollution and mortality from respiratory causes].

PubMed

Eilstein, D

2009-12-01

Different designs can be used to analyze the relationships between respiratory mortality and long term exposure to atmospheric pollution: epidemiological studies (cohort, prevalence study) demonstrate the reality of the relationship and toxicological studies explain it. Cohort studies have the advantage of being able to take into account many confounding factors and thus avoid biases (which is not the case with prevalence studies), but require significant human and financial resources. They were first adopted in the US, but are now more often applied in Europe. The results are relatively consistent, as they all show a statistically significant association between an increase in particulate pollution and cardiopulmonary mortality. Mortality from lung cancer is also associated with long term exposition to particles and sometimes to ozone or nitrogen oxides. Cerebrovascular diseases and sudden death of young children have also been associated with particulate pollution. The relationships are more powerful for long term than short term exposure but are also linear and without threshold. In order to explain these effects (today the causality of the relationship is certain) there are many possible factors, particularly regarding particulate exposures: an increase in cardiovascular risk biomarkers (fibrinogen, white blood cells, and platelets), atherosclerosis, chronic inflammation of lung tissues increased by acute exposure, etc. More and more studies address the interaction between gene and environment and even epigenetic phenomena which could be responsible of these effects. Public Health impact could be quantified. The European E&H surveillance program Apheis, for example, estimated that if PM2.5 levels remained below 15 microg/m(3), a 30 year old person could see his life expectancy increased by 1 month to 2 years, depending on the studied city. Finally, mortality is not the only relevant indicator for health effects of air pollution. ISAAC studies address asthma

Ecosystem Consequences of Prolonged Ozone Pollution in the Southern Sierra Nevada

NASA Astrophysics Data System (ADS)

Cousins, S.; Battles, J. J.; Cisneros, R.; Esperanza, A.; Swenson, D.

2015-12-01

While acute O3 exposure is widely known to damage plant tissues, the chronic effects on long lived organisms such as trees remain unclear. In the southern Sierra Nevada, O3 pollution has afflicted pine-dominated forests for over 40 years. Here we report the results of a long-term study of O3 impact on tree injury, growth, and mortality. Our study employed a network of forest plots along a gradient of O3 pollution with recurring measurements from 1991-2012. Over the same period and locations, summer O3 was monitored via partnership with USNPS and USFS, making this one of the longest known ecosystem studies of O3 pollution and its effects. We found that exposure at the most polluted sites declined 33%, from a W126 index of 20.12 ppm-hrs in 1992 to 13.5 ppm-hrs in 2012. The severity of foliar pollution damage at these sites also declined, from 43.9 on the 0-100 Ozone Injury Index (OII) scale to 34.2, a drop of 22%. At locations with lower O3 exposure, damage declined from OII of 16.9 to 9.2. Mean annual tree mortality rates over the 20 year period, calculated with a profile likelihood approach, were 0.5%/yr (95% CI 0.3 to 0.8 %/yr). This rate is similar to that of healthy canopy trees in similar unpolluted stands. However, low and declining tree growth rates reveal possible ecosystem impacts of prolonged exposure to pollution. Across affected sites, mean relative growth rates were 1.1%/yr in 1991-2000, and just 0.9%/yr in 2000-2011, a decline of 15.6% in the second decade. Initial analyses suggest that tree damage is positively correlated with June-October O3, as indicated by previous studies. Further analysis will explore the drivers of ecosystem impacts and roles of other natural and anthropogenic stressors, including variation in climatic water deficit. Understanding the consequences of prolonged O3 exposure on both individual trees and complex forest ecosystems helps identify the hidden environmental costs of tropospheric O3 and potential benefits of cleaner air.

Assessment of the effect of population and diary sampling methods on estimation of school-age children exposure to fine particles.

PubMed

Che, W W; Frey, H Christopher; Lau, Alexis K H

2014-12-01

Population and diary sampling methods are employed in exposure models to sample simulated individuals and their daily activity on each simulation day. Different sampling methods may lead to variations in estimated human exposure. In this study, two population sampling methods (stratified-random and random-random) and three diary sampling methods (random resampling, diversity and autocorrelation, and Markov-chain cluster [MCC]) are evaluated. Their impacts on estimated children's exposure to ambient fine particulate matter (PM2.5 ) are quantified via case studies for children in Wake County, NC for July 2002. The estimated mean daily average exposure is 12.9 μg/m(3) for simulated children using the stratified population sampling method, and 12.2 μg/m(3) using the random sampling method. These minor differences are caused by the random sampling among ages within census tracts. Among the three diary sampling methods, there are differences in the estimated number of individuals with multiple days of exposures exceeding a benchmark of concern of 25 μg/m(3) due to differences in how multiday longitudinal diaries are estimated. The MCC method is relatively more conservative. In case studies evaluated here, the MCC method led to 10% higher estimation of the number of individuals with repeated exposures exceeding the benchmark. The comparisons help to identify and contrast the capabilities of each method and to offer insight regarding implications of method choice. Exposure simulation results are robust to the two population sampling methods evaluated, and are sensitive to the choice of method for simulating longitudinal diaries, particularly when analyzing results for specific microenvironments or for exposures exceeding a benchmark of concern. © 2014 Society for Risk Analysis.

Spatial distribution of diesel transit bus emissions and urban populations: implications of coincidence and scale on exposure.

PubMed

Gouge, Brian; Ries, Francis J; Dowlatabadi, Hadi

2010-09-15

Macroscale emissions modeling approaches have been widely applied in impact assessments of mobile source emissions. However, these approaches poorly characterize the spatial distribution of emissions and have been shown to underestimate emissions of some pollutants. To quantify the implications of these limitations on exposure assessments, CO, NO(X), and HC emissions from diesel transit buses were estimated at 50 m intervals along a bus rapid transit route using a microscale emissions modeling approach. The impacted population around the route was estimated using census, pedestrian count and transit ridership data. Emissions exhibited significant spatial variability. In intervals near major intersections and bus stops, emissions were 1.6-3.0 times higher than average. The coincidence of these emission hot spots and peaks in pedestrian populations resulted in a 20-40% increase in exposure compared to estimates that assumed homogeneous spatial distributions of emissions and/or populations along the route. An additional 19-30% increase in exposure resulted from the underestimate of CO and NO(X) emissions by macroscale modeling approaches. The results of this study indicate that macroscale modeling approaches underestimate exposure due to poor characterization of the influence of vehicle activity on the spatial distribution of emissions and total emissions.

Targeted benefits of prolonged-infusion piperacillin-tazobactam in an in vitro infection model of Pseudomonas aeruginosa.

PubMed

Zelenitsky, S; Nash, J; Weber, Z; Iacovides, H; Ariano, R

2016-10-01

Given the inconsistent clinical findings, our goal was to characterize the pharmacodynamics (PDs) of prolonged-infusion piperacillin-tazobactam (TZP) in an in vitro pharmacodynamic model of Pseudomonas aeruginosa. Specifically, the study was designed to investigate the influence of MIC on the activity of prolonged-infusion TZP using pharmacokinetics (PKs) consistent with a non-critically ill patient population. There was no benefit with prolonged- compared with standard-infusion TZP against isolates with susceptible MICs of 8 or 16 mg/L. However, prolonged-infusion TZP produced more than two times the final bacterial kill against less susceptible isolates with an intermediate MIC of 32 mg/L. The PDs of TZP were well described by a sigmoid Emax model (r(2) = 0.84) where %ƒT>MIC thresholds of 27 and 75% were associated with bacteriostatic and bactericidal effects, respectively. However, the well-established PD relationship with %ƒT>MIC was not observed with prolonged-infusion TZP. In conclusion, this study characterizes the targeted benefits of prolong-infusion TZP based on pathogen MIC, and supports the assertion that the benefits are selective and most likely observed in patients with less susceptible pathogens or altered PKs.

Quantification of Acute Vocal Fold Epithelial Surface Damage with Increasing Time and Magnitude Doses of Vibration Exposure

PubMed Central

Kojima, Tsuyoshi; Van Deusen, Mark; Jerome, W. Gray; Garrett, C. Gaelyn; Sivasankar, M. Preeti; Novaleski, Carolyn K.; Rousseau, Bernard

2014-01-01

Because the vocal folds undergo repeated trauma during continuous cycles of vibration, the epithelium is routinely susceptible to damage during phonation. Excessive and prolonged vibration exposure is considered a significant predisposing factor in the development of vocal fold pathology. The purpose of the present study was to quantify the extent of epithelial surface damage following increased time and magnitude doses of vibration exposure using an in vivo rabbit phonation model. Forty-five New Zealand white breeder rabbits were randomized to nine groups and received varying phonation time-doses (30, 60, or 120 minutes) and magnitude-doses (control, modal intensity phonation, or raised intensity phonation) of vibration exposure. Scanning electron microscopy and transmission electron microscopy was used to quantify the degree of epithelial surface damage. Results revealed a significant reduction in microprojection density, microprojection height, and depth of the epithelial surface with increasing time and phonation magnitudes doses, signifying increased epithelial surface damage risk with excessive and prolonged vibration exposure. Destruction to the epithelial cell surface may provide significant insight into the disruption of cell function following prolonged vibration exposure. One important goal achieved in the present study was the quantification of epithelial surface damage using objective imaging criteria. These data provide an important foundation for future studies of long-term tissue recovery from excessive and prolonged vibration exposure. PMID:24626217

Simulation of population-based commuter exposure to NO₂ using different air pollution models.

PubMed

Ragettli, Martina S; Tsai, Ming-Yi; Braun-Fahrländer, Charlotte; de Nazelle, Audrey; Schindler, Christian; Ineichen, Alex; Ducret-Stich, Regina E; Perez, Laura; Probst-Hensch, Nicole; Künzli, Nino; Phuleria, Harish C

2014-05-12

We simulated commuter routes and long-term exposure to traffic-related air pollution during commute in a representative population sample in Basel (Switzerland), and evaluated three air pollution models with different spatial resolution for estimating commute exposures to nitrogen dioxide (NO2) as a marker of long-term exposure to traffic-related air pollution. Our approach includes spatially and temporally resolved data on actual commuter routes, travel modes and three air pollution models. Annual mean NO2 commuter exposures were similar between models. However, we found more within-city and within-subject variability in annual mean (±SD) NO2 commuter exposure with a high resolution dispersion model (40 ± 7 µg m(-3), range: 21-61) than with a dispersion model with a lower resolution (39 ± 5 µg m(-3); range: 24-51), and a land use regression model (41 ± 5 µg m(-3); range: 24-54). Highest median cumulative exposures were calculated along motorized transport and bicycle routes, and the lowest for walking. For estimating commuter exposure within a city and being interested also in small-scale variability between roads, a model with a high resolution is recommended. For larger scale epidemiological health assessment studies, models with a coarser spatial resolution are likely sufficient, especially when study areas include suburban and rural areas.

Occupational Exposure to Benzene and Non-Hodgkin Lymphoma in a Population-Based Cohort: The Shanghai Women’s Health Study

PubMed Central

Friesen, Melissa C.; Vermeulen, Roel; Shu, Xiao-Ou; Purdue, Mark P.; Stewart, Patricia A.; Xiang, Yong-Bing; Chow, Wong-Ho; Zheng, Tongzhang; Ji, Bu-Tian; Yang, Gong; Linet, Martha S.; Hu, Wei; Zhang, Heping; Zheng, Wei; Gao, Yu-Tang; Rothman, Nathaniel; Lan, Qing

2015-01-01

Background The association between benzene exposure and non-Hodgkin lymphoma (NHL) has been the subject of debate as a result of inconsistent epidemiologic evidence. An International Agency for Research on Cancer (IARC) working group evaluated benzene in 2009 and noted evidence for a positive association between benzene exposure and NHL risk. Objective We evaluated the association between occupational benzene exposure and NHL among 73,087 women enrolled in the prospective population-based Shanghai Women’s Health Study. Methods Benzene exposure estimates were derived using a previously developed exposure assessment framework that combined ordinal job-exposure matrix intensity ratings with quantitative benzene exposure measurements from an inspection database of Shanghai factories collected between 1954 and 2000. Associations between benzene exposure metrics and NHL (n = 102 cases) were assessed using Cox proportional hazard models, with study follow-up occurring from December 1996 through December 2009. Results Women ever exposed to benzene had a significantly higher risk of NHL [hazard ratio (HR) = 1.87, 95% CI: 1.19, 2.96]. Compared with unexposed women, significant trends in NHL risk were observed for increasing years of benzene exposure (ptrend = 0.006) and increasing cumulative exposure levels (ptrend = 0.005), with the highest duration and cumulative exposure tertiles having a significantly higher association with NHL (HR = 2.07, 95% CI: 1.07, 4.01 and HR = 2.16, 95% CI: 1.17, 3.98, respectively). Conclusions Our findings, using a population-based prospective cohort of women with diverse occupational histories, provide additional evidence that occupational exposure to benzene is associated with NHL risk. Citation Bassig BA, Friesen MC, Vermeulen R, Shu XO, Purdue MP, Stewart PA, Xiang YB, Chow WH, Zheng T, Ji BT, Yang G, Linet MS, Hu W, Zhang H, Zheng W, Gao YT, Rothman N, Lan Q. 2015. Occupational exposure to benzene and non-Hodgkin lymphoma in a population

Occupational Exposure to Benzene and Non-Hodgkin Lymphoma in a Population-Based Cohort: The Shanghai Women's Health Study.

PubMed

Bassig, Bryan A; Friesen, Melissa C; Vermeulen, Roel; Shu, Xiao-Ou; Purdue, Mark P; Stewart, Patricia A; Xiang, Yong-Bing; Chow, Wong-Ho; Zheng, Tongzhang; Ji, Bu-Tian; Yang, Gong; Linet, Martha S; Hu, Wei; Zhang, Heping; Zheng, Wei; Gao, Yu-Tang; Rothman, Nathaniel; Lan, Qing

2015-10-01

The association between benzene exposure and non-Hodgkin lymphoma (NHL) has been the subject of debate as a result of inconsistent epidemiologic evidence. An International Agency for Research on Cancer (IARC) working group evaluated benzene in 2009 and noted evidence for a positive association between benzene exposure and NHL risk. We evaluated the association between occupational benzene exposure and NHL among 73,087 women enrolled in the prospective population-based Shanghai Women's Health Study. Benzene exposure estimates were derived using a previously developed exposure assessment framework that combined ordinal job-exposure matrix intensity ratings with quantitative benzene exposure measurements from an inspection database of Shanghai factories collected between 1954 and 2000. Associations between benzene exposure metrics and NHL (n = 102 cases) were assessed using Cox proportional hazard models, with study follow-up occurring from December 1996 through December 2009. Women ever exposed to benzene had a significantly higher risk of NHL [hazard ratio (HR) = 1.87, 95% CI: 1.19, 2.96]. Compared with unexposed women, significant trends in NHL risk were observed for increasing years of benzene exposure (p(trend) = 0.006) and increasing cumulative exposure levels (p(trend) = 0.005), with the highest duration and cumulative exposure tertiles having a significantly higher association with NHL (HR = 2.07, 95% CI: 1.07, 4.01 and HR = 2.16, 95% CI: 1.17, 3.98, respectively). Our findings, using a population-based prospective cohort of women with diverse occupational histories, provide additional evidence that occupational exposure to benzene is associated with NHL risk.

Occupational exposure to chemicals drives the increased risk of asthma and rhinitis observed for exposure to vapours, gas, dust and fumes: a cross-sectional population-based study.

PubMed

Schyllert, Christian; Rönmark, Eva; Andersson, Martin; Hedlund, Ulf; Lundbäck, Bo; Hedman, Linnea; Lindberg, Anne

2016-10-01

Occupational exposure to the composite measure vapours, gases, dusts and fumes (VGDF), contribute to the burden of asthma and rhinitis. The objective was to evaluate occupational exposure to VGDF, which is further divided into the components chemicals, organic and inorganic dust in relation to asthma and rhinitis. Previously examined participants from three population-based cohorts in the Obstructive Lung disease In Northern Sweden (OLIN) studies were re-examined during 2002-2004. In total, 4036 participated in a structured interview and answered a questionnaire on occupational exposures. Occupational exposure to VGDF increased the risk of asthma, and concomitant asthma and rhinitis. Exposure to chemicals, but not dust, showed a similar pattern. Exposure to chemicals increased the risks (OR, 95% CI) of rhinitis without asthma (1.29, 1.10 to 1.52), asthma without rhinitis (1.42, 1.15 to 1.77) and concomitant asthma and rhinitis (1.60, 1.31 to 1.96) when adjusted for confounders such as age, smoking habits, body mass index and sex. The association between exposure to chemicals and asthma and rhinitis remained independent of exposure to dust and was also so when excluding exposure to isocyanates and welding fumes. The results were similar for women and men, as well as for never-smokers and participants without a history of allergy. In this cross-sectional population-based study, occupational exposure to chemicals contributed substantially to the increased risk of asthma and rhinitis observed for occupational exposure to VGDF. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Fluoride exposure and indicators of thyroid functioning in the Canadian population: implications for community water fluoridation.

PubMed

Barberio, Amanda M; Hosein, F Shaun; Quiñonez, Carlos; McLaren, Lindsay

2017-10-01

There are concerns that altered thyroid functioning could be the result of ingesting too much fluoride. Community water fluoridation (CWF) is an important source of fluoride exposure. Our objectives were to examine the association between fluoride exposure and (1) diagnosis of a thyroid condition and (2) indicators of thyroid functioning among a national population-based sample of Canadians. We analysed data from Cycles 2 and 3 of the Canadian Health Measures Survey (CHMS). Logistic regression was used to assess associations between fluoride from urine and tap water samples and the diagnosis of a thyroid condition. Multinomial logistic regression was used to examine the relationship between fluoride exposure and thyroid-stimulating hormone (TSH) level (low/normal/high). Other available variables permitted additional exploratory analyses among the subset of participants for whom we could discern some fluoride exposure from drinking water and/or dental products. There was no evidence of a relationship between fluoride exposure (from urine and tap water) and the diagnosis of a thyroid condition. There was no statistically significant association between fluoride exposure and abnormal (low or high) TSH levels relative to normal TSH levels. Rerunning the models with the sample constrained to the subset of participants for whom we could discern some source(s) of fluoride exposure from drinking water and/or dental products revealed no significant associations. These analyses suggest that, at the population level, fluoride exposure is not associated with impaired thyroid functioning in a time and place where multiple sources of fluoride exposure, including CWF, exist. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

New Rodent Population Models May Inform Human Health Risk Assessment and Identification of Genetic Susceptibility to Environmental Exposures.

PubMed

Harrill, Alison H; McAllister, Kimberly A

2017-08-15

This paper provides an introduction for environmental health scientists to emerging population-based rodent resources. Mouse reference populations provide an opportunity to model environmental exposures and gene-environment interactions in human disease and to inform human health risk assessment. This review will describe several mouse populations for toxicity assessment, including older models such as the Mouse Diversity Panel (MDP), and newer models that include the Collaborative Cross (CC) and Diversity Outbred (DO) models. This review will outline the features of the MDP, CC, and DO mouse models and will discuss published case studies investigating the use of these mouse population resources in each step of the risk assessment paradigm. These unique resources have the potential to be powerful tools for generating hypotheses related to gene-environment interplay in human disease, performing controlled exposure studies to understand the differential responses in humans for susceptibility or resistance to environmental exposures, and identifying gene variants that influence sensitivity to toxicity and disease states. These new resources offer substantial advances to classical toxicity testing paradigms by including genetically sensitive individuals that may inform toxicity risks for sensitive subpopulations. Both in vivo and complementary in vitro resources provide platforms with which to reduce uncertainty by providing population-level data around biological variability. https://doi.org/10.1289/EHP1274.

Effect of prolonged incubation with copper on endothelium-dependent relaxation in rat isolated aorta

PubMed Central

Chiarugi, Alberto; Pitari, Giovanni Mario; Costa, Rosa; Ferrante, Margherita; Villari, Loredana; Amico-Roxas, Matilde; Godfraind, Théophile; Bianchi, Alfredo; Salomone, Salvatore

2002-01-01

We investigated the effects of prolonged exposure to copper (Cu2+) on vascular functioning of isolated rat aorta. Aortic rings were exposed to CuSO4 (3–24 h) in Dulbecco's modified Eagle medium with or without 10% foetal bovine serum (FBS) and then challenged with vasoconstrictors or vasodilators in the absence of Cu2+. Exposure to 2 μM Cu2+ in the absence of FBS did not modify the response to phenylephrine (PE) or acetylcholine (ACh) in aortic rings incubated for 24 h. Identical exposure in the presence of FBS increased the contractile response to 1 μM PE by 30% (P<0.05) and impaired the relaxant response to 3 μM ACh or 1 μM A23187 (ACh, from 65.7±7.1 to 6.2±1.1%, n=8; A23187, from 74.6±8.2 to 12.0±0.8%, n=6; P<0.01 for both). Cu2+ exposure did not affect the relaxant response to NO-donors. Impairment of vasorelaxation appeared 3 h after incubation with 2 μM Cu2+ and required 12 h to attain a steady state. Vasorelaxation to ACh was partially restored by 1 mM tiron (intracellular scavenger of superoxide ions; maximum relaxation 34.2±6.4%, n=10, P<0.01 vs Cu2+ alone), whereas catalase, superoxide dismutase or cycloheximide were ineffective. Twenty-four hour-exposure to 2 μM Cu2+ did not affect endothelium integrity or eNOS expression, and increased the Cu content in arterial rings from 6.8±1.1 to 18.9±2.9 ng mg−1 wet weight, n=8; P<0.01. Our results show that, in the presence of FBS, prolonged exposure to submicromolar concentrations of Cu2+ impaired endothelium-dependent vasorelaxation in aortic rings, probably through an intracellular generation of superoxide ions. PMID:12163352

The modifying effect of the building envelope on population exposure to PM2.5 from outdoor sources.

PubMed

Taylor, J; Shrubsole, C; Davies, M; Biddulph, P; Das, P; Hamilton, I; Vardoulakis, S; Mavrogianni, A; Jones, B; Oikonomou, E

2014-12-01

A number of studies have estimated population exposure to PM2.5 by examining modeled or measured outdoor PM2.5 levels. However, few have taken into account the mediating effects of building characteristics on the ingress of PM2.5 from outdoor sources and its impact on population exposure in the indoor domestic environment. This study describes how building simulation can be used to determine the indoor concentration of outdoor-sourced pollution for different housing typologies and how the results can be mapped using building stock models and Geographical Information Systems software to demonstrate the modifying effect of dwellings on occupant exposure to PM2.5 across London. Building archetypes broadly representative of those in the Greater London Authority were simulated for pollution infiltration using EnergyPlus. In addition, the influence of occupant behavior on indoor levels of PM2.5 from outdoor sources was examined using a temperature-dependent window-opening scenario. Results demonstrate a range of I/O ratios of PM2.5 , with detached and semi-detached dwellings most vulnerable to high levels of infiltration. When the results are mapped, central London shows lower I/O ratios of PM2.5 compared with outer London, an apparent inversion of exposure most likely caused by the prevalence of flats rather than detached or semi-detached properties. Population exposure to air pollution is typically evaluated using the outdoor concentration of pollutants and does not account for the fact that people in London spend over 80% of their time indoors. In this article, building simulation is used to model the infiltration of outdoor PM2.5 into the domestic indoor environment for dwellings in a London building stock model, and the results mapped. The results show the variation in relative vulnerability of dwellings to pollution infiltration, as well as an estimated absolute indoor concentration across the Greater London Authority (GLA) scaled by local outdoor levels. The

Clinical dysphagia risk predictors after prolonged orotracheal intubation.

PubMed

Medeiros, Gisele Chagas de; Sassi, Fernanda Chiarion; Mangilli, Laura Davison; Zilberstein, Bruno; Andrade, Claudia Regina Furquim de

2014-01-01

To elucidate independent risk factors for dysphagia after prolonged orotracheal intubation. The participants were 148 consecutive patients who underwent clinical bedside swallowing assessments from September 2009 to September 2011. All patients had received prolonged orotracheal intubations and were admitted to one of several intensive care units of a large Brazilian school hospital. The correlations between the conducted water swallow test results and dysphagia risk levels were analyzed for statistical significance. Of the 148 patients included in the study, 91 were male and 57 were female (mean age, 53.64 years). The univariate analysis results indicated that specific variables, including extraoral loss, multiple swallows, cervical auscultation, vocal quality, cough, choking, and other signs, were possible significant high-risk indicators of dysphagia onset. The multivariate analysis results indicated that cervical auscultation and coughing were independent predictive variables for high dysphagia risk. Patients displaying extraoral loss, multiple swallows, cervical auscultation, vocal quality, cough, choking and other signs should benefit from early swallowing evaluations. Additionally, early post-extubation dysfunction recognition is paramount in reducing the morbidity rate in this high-risk population.

Inhibition of spontaneous recovery of fear by mGluR5 after prolonged extinction training.

PubMed

Mao, Sheng-Chun; Chang, Chih-Hua; Wu, Chia-Chen; Orejarena, M Juliana; Orejanera, Maria Juliana; Manzoni, Olivier J; Gean, Po-Wu

2013-01-01

Fear behavior is vital for survival and involves learning contingent associations of non-threatening cues with aversive stimuli. In contrast, excessive levels of fear can be maladaptive and lead to anxiety disorders. Generally, extensive sessions of extinction training correlates with reduced spontaneous recovery. The molecular mechanisms underlying the long-term inhibition of fear recovery following repeated extinction training are not fully understood. Here we show that in rats, prolonged extinction training causes greater reduction in both fear-potentiated startle and spontaneous recovery. This effect was specifically blocked by metabotropic glutamate receptor 5 (mGluR5), but not by mGluR1 antagonists and by a protein synthesis inhibitor. Similar inhibition of memory recovery following prolonged extinction training was also observed in mice. In agreement with the instrumental role of mGluR5 in the prolonged inhibition of fear recovery, we found that FMR1-/- mice which exhibit enhanced mGluR5-mediated signaling exhibit lower spontaneous recovery of fear after extinction training than wild-type littermates. At the molecular level, we discovered that prolonged extinction training reversed the fear conditioning-induced increase in surface expression of GluR1, AMPA/NMDA ratio, postsynaptic density-95 (PSD-95) and synapse-associated protein-97 (SAP97). Accordingly, delivery of Tat-GluR2(3Y), a synthetic peptide that blocks AMPA receptor endocytosis, inhibited prolonged extinction training-induced inhibition of fear recovery. Together, our results demonstrate that prolonged extinction training results in the mGluR5-dependent long-term inhibition of fear recovery. This effect may involve the degradation of original memory and may explain the beneficial effects of prolonged exposure therapy for the treatment of phobias.

Single Intravenous Dose of Novel Flurbiprofen-Loaded Proniosome Formulations Provides Prolonged Systemic Exposure and Anti-inflammatory Effect.

PubMed

Verma, Preeti; Prajapati, Sunil K; Yadav, Rajbharan; Senyschyn, Danielle; Shea, Peter R; Trevaskis, Natalie L

2016-11-07

hydrated proniosomes can prolong systemic drug exposure over 3 days and provide a sustained therapeutic effect. The developed proniosomes represent a novel approach to treat acute pain and inflammation with the potential to be administered as a single intravenous dose by a clinician at the time of injury or surgery that provides adequate relief for several days and reduces fluctuations in therapy. Similar systems loaded with different drugs have potential for broader application in anesthesia, anti-infective, antiemetic, and cancer therapy.

Prolonged grief symptoms related to loss of physical functioning: examining unique associations with medical service utilization.

PubMed

Holland, Jason M; Graves, Stacy; Klingspon, Kara L; Rozalski, Vincent

2016-01-01

Prolonged grief, a severe and chronic form of grieving most commonly studied in the context of bereavement, may have relevance to losses associated with chronic illness (e.g. grief related to loss of functioning or loss of a planned future). The purpose of the present study is to examine the unique associations between prolonged grief symptoms and service utilization patterns. An online self-report assessment battery was administered among a sample of 275 older adults with at least one chronic illness that caused significant physical impairment. Even after statistically controlling for relevant physical health (e.g. severity of physical limitations, somatic symptoms, number of chronic illnesses) and psychosocial variables (e.g. social support, depression/anxiety), more severe prolonged grief symptoms were associated with a greater number of emergency room visits, overnight stays in the hospital and total nights in the hospital. These findings highlight the importance of screening for prolonged grief symptomatology with older individuals with a debilitating chronic illness. Recent evidence suggests that prolonged grief may have relevance for losses associated with physical illness. The present study shows that prolonged grief reactions related to physical illness (e.g. grieving the loss of functioning) are uniquely associated with increased hospital-based service utilization. Given the relevance of prolonged grief reactions in this population, practitioners may wish to assess for these symptoms. Future clinical research should focus on developing interventions to target prolonged grief symptoms associated with these losses.

General Population Job Exposure Matrix Applied to a Pooled Study of Prevalent Carpal Tunnel Syndrome

PubMed Central

Dale, Ann Marie; Zeringue, Angelique; Harris-Adamson, Carisa; Rempel, David; Bao, Stephen; Thiese, Matthew S.; Merlino, Linda; Burt, Susan; Kapellusch, Jay; Garg, Arun; Gerr, Fred; Hegmann, Kurt T.; Eisen, Ellen A.; Evanoff, Bradley

2015-01-01

A job exposure matrix may be useful for the study of biomechanical workplace risk factors when individual-level exposure data are unavailable. We used job title–based exposure data from a public data source to construct a job exposure matrix and test exposure-response relationships with prevalent carpal tunnel syndrome (CTS). Exposures of repetitive motion and force from the Occupational Information Network were assigned to 3,452 active workers from several industries, enrolled between 2001 and 2008 from 6 studies. Repetitive motion and force exposures were combined into high/high, high/low, and low/low exposure groupings in each of 4 multivariable logistic regression models, adjusted for personal factors. Although force measures alone were not independent predictors of CTS in these data, strong associations between combined physical exposures of force and repetition and CTS were observed in all models. Consistent with previous literature, this report shows that workers with high force/high repetition jobs had the highest prevalence of CTS (odds ratio = 2.14–2.95) followed by intermediate values (odds ratio = 1.09–2.27) in mixed exposed jobs relative to the lowest exposed workers. This study supports the use of a general population job exposure matrix to estimate workplace physical exposures in epidemiologic studies of musculoskeletal disorders when measures of individual exposures are unavailable. PMID:25700886

COMPARISONS OF PESTICIDE LEVELS AND EXPOSURES IN NHEXAS ARIZONA AND ARIZONA-MEXICO BORDER POPULATIONS

EPA Science Inventory

The distributions of organophosphate (OP) insecticides chlorpyrifos and diazinon in exposure matrices such as indoor air, house dust, food, and water have been determined for 416 homes in the general Arizona population, and for 87 homes along the Arizona-Mexico border. The con...

Renal Function in De Novo Liver Transplant Recipients Receiving Different Prolonged-Release Tacrolimus Regimens-The DIAMOND Study.

PubMed

TruneČka, P; Klempnauer, J; Bechstein, W O; Pirenne, J; Friman, S; Zhao, A; Isoniemi, H; Rostaing, L; Settmacher, U; Mönch, C; Brown, M; Undre, N; Tisone, G

2015-07-01

DIAMOND: multicenter, 24-week, randomized trial investigating the effect of different once-daily, prolonged-release tacrolimus dosing regimens on renal function after de novo liver transplantation. Arm 1: prolonged-release tacrolimus (initial dose 0.2mg/kg/day); Arm 2: prolonged-release tacrolimus (0.15-0.175mg/kg/day) plus basiliximab; Arm 3: prolonged-release tacrolimus (0.2mg/kg/day delayed until Day 5) plus basiliximab. All patients received MMF plus a bolus of corticosteroid (no maintenance steroids). eGFR (MDRD4) at Week 24. Secondary endpoints: composite efficacy failure, BCAR and AEs. Baseline characteristics were comparable. Tacrolimus trough levels were readily achieved posttransplant; initially lower in Arm 2 versus 1 with delayed initiation in Arm 3. eGFR (MDRD4) was higher in Arms 2 and 3 versus 1 (p = 0.001, p = 0.047). Kaplan-Meier estimates of composite efficacy failure-free survival were 72.0%, 77.6%, 73.9% in Arms 1-3. BCAR incidence was significantly lower in Arm 2 versus 1 and 3 (p = 0.016, p = 0.039). AEs were comparable. Prolonged-release tacrolimus (0.15-0.175mg/kg/day) immediately posttransplant plus basiliximab and MMF (without maintenance corticosteroids) was associated with lower tacrolimus exposure, and significantly reduced renal function impairment and BCAR incidence versus prolonged-release tacrolimus (0.2mg/kg/day) administered immediately posttransplant. Delayed higher-dose prolonged-release tacrolimus initiation significantly reduced renal function impairment compared with immediate posttransplant administration, but BCAR incidence was comparable. © 2015 The Authors. American Journal of Transplantation published by Wiley Periodicals Inc.

Prolonged CT urography in duplex kidney.

PubMed

Gong, Honghan; Gao, Lei; Dai, Xi-Jian; Zhou, Fuqing; Zhang, Ning; Zeng, Xianjun; Jiang, Jian; He, Laichang

2016-05-13

Duplex kidney is a common anomaly that is frequently associated with multiple complications. Typical computed tomography urography (CTU) includes four phases (unenhanced, arterial, parenchymal and excretory) and has been suggested to considerably aid in the duplex kidney diagnosi. Unfortunately, regarding duplex kidney with prolonged dilatation, the affected parenchyma and tortuous ureters demonstrate a lack of or delayed excretory opacification. We used prolonged-delay CTU, which consists of another prolonged-delay phase (1- to 72-h delay; mean delay: 24 h) to opacify the duplicated ureters and affected parenchyma. Seventeen patients (9 males and 8 females; age range: 2.5-56 y; mean age: 40.4 y) with duplex kidney were included in this study. Unenhanced scans did not find typical characteristics of duplex kidney, except for irregular perirenal morphology. Duplex kidney could not be confirmed on typical four-phase CTU, whereas it could be easily diagnosed in axial and CT-3D reconstruction using prolonged CTU (prolonged-delay phase). Between January 2005 and October 2010, in this review board-approved study (with waived informed consent), 17 patients (9 males and 8 females; age range: 2.5 ~ 56 y; mean age: 40.4 y) with suspicious duplex kidney underwent prolonged CTU to opacify the duplicated ureters and confirm the diagnosis. Our results suggest the validity of prolonged CTU to aid in the evaluation of the function of the affected parenchyma and in the demonstration of urinary tract malformations.

Stimulation of cardiovascular adaptability during prolonged space exposure

NASA Technical Reports Server (NTRS)

Gorman, H. A.

1971-01-01

The deconditioning effects of weightlessness on the cardiovascular system of astronauts are discussed. It is believed that man cannot tolerate indefinite exposure to weightlessness without considerable circulatory deterioration. Analyses of data collected from space flights to date substantiate these beliefs, and confirm the fact that some form of compensation must be provided to keep the cardiovascular system of space travelers properly conditioned. Sequential pulsatile devices were investigated to produce periodic hydrostatic pressure gradients in the venous system of eight subhuman primates. Intermittent venous pooling of blood in the extremities triggers and stimulates the vascular reflex mechanisms of the cardiovascular system that may have significant benefits in maintaining the circulatory system in proper tone under weightless conditions. Electrocardiograms, blood pressure measurements, cardiac output and stroke volume determinations were used to evaluate the efficiency of the described technique. Results were amazingly consistent to indicate an efficient system for intermittently exercising the heart within safe and medically acceptable limits.

Xenon treatment protects against cold ischemia associated delayed graft function and prolongs graft survival in rats.

PubMed

Zhao, H; Watts, H R; Chong, M; Huang, H; Tralau-Stewart, C; Maxwell, P H; Maze, M; George, A J T; Ma, D

2013-08-01

Prolonged hypothermic storage causes ischemia-reperfusion injury (IRI) in the renal graft, which is considered to contribute to the occurrence of the delayed graft function (DGF) and chronic graft failure. Strategies are required to protect the graft and to prolong renal graft survival. We demonstrated that xenon exposure to human proximal tubular cells (HK-2) led to activation of range of protective proteins. Xenon treatment prior to or after hypothermia-hypoxia challenge stabilized the HK-2 cellular structure, diminished cytoplasmic translocation of high-mobility group box (HMGB) 1 and suppressed NF-κB activation. In the syngeneic Lewis-to-Lewis rat model of kidney transplantation, xenon exposure to donors before graft retrieval or to recipients after engraftment decreased caspase-3 expression, localized HMGB-1 within nuclei and prevented TLR-4/NF-κB activation in tubular cells; serum pro-inflammatory cytokines IL-1β, IL-6 and TNF-α were reduced and renal function was preserved. Xenon treatment of graft donors or of recipients prolonged renal graft survival following IRI in both Lewis-to-Lewis isografts and Fischer-to-Lewis allografts. Xenon induced cell survival or graft functional recovery was abolished by HIF-1α siRNA. Our data suggest that xenon treatment attenuates DGF and enhances graft survival. This approach could be translated into clinical practice leading to a considerable improvement in long-term graft survival. © Copyright 2013 The American Society of Transplantation and the American Society of Transplant Surgeons.

Post-training Beliefs, Intentions, and Use of Prolonged Exposure Therapy by Clinicians in the Veterans Health Administration.

PubMed

Ruzek, J I; Eftekhari, A; Crowley, J; Kuhn, E; Karlin, B E; Rosen, C S

2017-01-01

To examine how changes in beliefs during the training process predict adoption of prolonged exposure therapy (PE) by veterans health administration clinicians who received intensive training in this evidence-based treatment. Participants completed a 4-day PE workshop and received expert consultation as they used PE with two or more training cases. Participants were surveyed prior to the workshop, after the workshop, after case consultation (n = 1.034), and 6 months after training (n = 810). Hierarchical regression was used to assess how pre-training factors, and changes in beliefs during different stages of training incrementally predicted post-training intent to use PE and how many patients clinicians were treating with PE 6 months after training. Post-training intent to use PE was high (mean = 6.2, SD = 0.81 on a 1-7 scale), yet most participants treated only 1 or 2 patients at a time with PE. Pre-training factors predicted intent to use and actual use of PE. Changes in beliefs during the workshop had statistically significant yet modest effects on intent and use of PE. Changes in beliefs during case consultation had substantial effects on intent and actual use of PE. Pre-training factors and changes in beliefs during training (especially during case consultation) influence clinicians' adoption of PE. Use of PE was influenced not only by its perceived clinical advantages/disadvantages, but also by contextual factors (working in a PTSD specialty clinic, perceived control over one's schedule, and ability to promote PE to patients and colleagues).

Beta-lactam antibiotic-induced platelet dysfunction: Evidence for irreversible inhibition of platelet activation in vitro and in vivo after prolonged exposure to penicillin

DOE Office of Scientific and Technical Information (OSTI.GOV)

Burroughs, S.F.; Johnson, G.J.

beta-Lactam antibiotics cause platelet dysfunction with bleeding complications. Previous in vitro studies documented reversible inhibition of agonist-receptor interaction. This mechanism is inadequate to explain the effect of beta-lactam antibiotics in vivo. Platelet function does not return to normal immediately after drug treatment, implying irreversible inhibition of platelet function. We report here evidence of irreversible platelet functional and biochemical abnormalities after in vitro and in vivo exposure to beta-lactam antibiotics. Irreversible binding of (14C)-penicillin (Pen) occurred in vitro. After 24 hours' in vitro incubation with 10 to 20 mmol/L Pen, or ex vivo after antibiotic treatment, irreversible functional impairment occurred; butmore » no irreversible inhibition of alpha 2 adrenergic receptors, measured with (3H)-yohimbine, or high-affinity thromboxane A2/prostaglandin H2 (TXA2/PGH2) receptors, measured with agonist (3H)-U46619 and antagonist (3H)-SQ29548, occurred. However, low-affinity platelet TXA2/PGH2 receptors were decreased 40% after Pen exposure in vitro or in vivo, indicating irreversible membrane alteration. Two postreceptor biochemical events were irreversibly inhibited in platelets incubated with Pen for 24 hours in vitro or ex vivo after antibiotic treatment. Thromboxane synthesis was inhibited 28.3% to 81.7%. Agonist-induced rises in cytosolic calcium ((Ca2+)i) were inhibited 40.1% to 67.5% in vitro and 26.6% to 52.2% ex vivo. Therefore, Pen binds to platelets after prolonged exposure, resulting in irreversible dysfunction attributable to inhibition of TXA2 synthesis and impairment of the rise in (Ca2+)i. The loss of low-affinity TXA2/PGH2 receptors suggests that the primary site of action of these drugs is on the platelet membrane.« less

Within- and among-population level differences in response to chronic copper exposure in southern toads, Anaxyrus terrestris.

PubMed

Lance, Stacey L; Flynn, R Wesley; Erickson, Matthew R; Scott, David E

2013-06-01

Environmental contaminants are implicated in the global decline of amphibian populations. Copper (Cu) is a widespread contaminant that can be toxic at concentrations just above the normal physiological range. In the present study we examined the effects of chronic Cu aqueous exposure on embryos and larvae of southern toads, Anaxyrus (Bufo) terrestris. Measurable levels of Cu were found in larvae, with tissue concentrations up to 27.5 μg Cu/g dry mass. Aqueous concentrations of Cu as low as 10 μg/L significantly reduced survival to the free-swimming stage and no larvae reached metamorphosis at concentrations above 15 μg/L. Clutches from populations with prior Cu exposure had the lowest survivorship. Among several populations there was significant variation in survivorship at different levels of Cu. More data are needed to understand the underlying causes of within- and among-population resilience to anthropogenic stressors. Copyright © 2013 Elsevier Ltd. All rights reserved.

Low extracellular potassium prolongs repolarization and evokes early afterdepolarization in human induced pluripotent stem cell-derived cardiomyocytes.

PubMed

Kuusela, Jukka; Larsson, Kim; Shah, Disheet; Prajapati, Chandra; Aalto-Setälä, Katriina

2017-06-15

Long QT syndrome (LQTS) is characterized by a prolonged QT-interval on electrocardiogram and by increased risk of sudden death. One of the most common and potentially life-threatening electrolyte disturbances is hypokalemia, characterized by low concentrations of K + Using a multielectrode array platform and current clamp technique, we investigated the effect of low extracellular K + concentration ([K + ] Ex ) on the electrophysiological properties of hiPSC-derived cardiomyocytes (CMs) generated from a healthy control subject (WT) and from two symptomatic patients with type 1 of LQTS carrying G589D (LQT1A) or IVS7-2A>G mutation (LQT1B) in KCNQ1 The baseline prolongations of field potential durations (FPDs) and action potential durations (APDs) were longer in LQT1-CMs than in WT-CMs. Exposure to low [K + ] Ex prolonged FPDs and APDs in a concentration-dependent fashion. LQT1-CMs were found to be more sensitive to low [K + ] Ex compared to WT-CMs. At baseline, LQT1A-CMs had more prolonged APDs than LQT1B-CMs, but low [K + ] Ex caused more pronounced APD prolongation in LQT1B-CMs. Early afterdepolarizations in the action potentials were observed in a subset of LQT1A-CMs with further prolonged baseline APDs and triangular phase 2 profiles. This work demonstrates that the hiPSC-derived CMs are sensitive to low [K + ] Ex and provide a platform to study acquired LQTS. © 2017. Published by The Company of Biologists Ltd.

Exposure of human melanocytes to UVB twice and subsequent incubation leads to cellular senescence and senescence-associated pigmentation through the prolonged p53 expression.

PubMed

Choi, Suh-Yeon; Bin, Bum-Ho; Kim, Wanil; Lee, Eunkyung; Lee, Tae Ryong; Cho, Eun-Gyung

2018-06-01

Ultraviolet radiation (UVR) is a well-known factor in skin aging and pigmentation, and daily exposure to subcytotoxic doses of UVR might accelerate senescence and senescence-associated phenomena in human melanocytes. To establish an in vitro melanocyte model to mimic the conditions of repeated exposure to subcytotoxic doses of UVB irradiation and to investigate key factor(s) for melanocyte senescence and senescence-associated phenomena. Human epidermal melanocytes were exposed twice with 20 mJ/cm 2 UVB over a 24-h interval and subsequently cultivated for 2 weeks. Senescent phenotypes were addressed morphologically, and by measuring the senescence-associated β-galactosidase (SA-β-Gal) activity, cell proliferation capacity with cell cycle analysis, and melanin content. The established protocol successfully induced melanocyte senescence, and senescent melanocytes accompanied hyperpigmentation. Prolonged expression of p53 was responsible for melanocyte senescence and hyperpigmentation, and treatment with the p53-inhibitor pifithrin-α at 2-weeks post-UVB irradiation, but not at 48 h, significantly reduced melanin content along with decreases in tyrosinase levels. Melanocyte senescence model will be useful for studying the long-term effects of UVB irradiation and pigmentation relevant to physiological photoaging, and screening compounds effective for senescence-associated p53-mediated pigmentation. Copyright © 2018 Japanese Society for Investigative Dermatology. Published by Elsevier B.V. All rights reserved.

Exposure Assessment Tools by Lifestages and Populations

EPA Pesticide Factsheets

EPA ExpoBox is a toolbox for exposure assessors. Its purpose is to provide a compendium of exposure assessment and risk characterization tools that will present comprehensive step-by-step guidance and links to relevant exposure assessment data bases

Survival of soil bacteria during prolonged desiccation.

NASA Technical Reports Server (NTRS)

Chen, M.; Alexander, M.

1973-01-01

A determination was made of the kinds and numbers of bacteria surviving when two soils were maintained in the laboratory under dry conditions for more than half a year. Certain non-spore-forming bacteria were found to survive in the dry condition for long periods. A higher percentage of drought-tolerant than drought-sensitive bacteria was able to grow at low water activities. When they were grown in media with high salt concentrations, bacteria generally became more tolerant of prolonged drought and they persisted longer. The percent of cells in a bacterial population that remained viable when exposed to drought stress varied with the stage of growth.

Forced migration and mental health: prolonged internal displacement, return migration and resilience.

PubMed

Siriwardhana, Chesmal; Stewart, Robert

2013-03-01

Forced internal displacement has been rising steadily, mainly due to conflict. Many internally displaced people (IDP) experience prolonged displacement. Global research evidence suggests that many of these IDP are at high risk for developing mental disorders, adding weight to the global burden of disease. However, individual and community resilience may act as protective factors. Return migration may be an option for some IDP populations, especially when conflicts end, although return migration may itself be associated with worse mental health. Limited evidence is available on effects of resettlement or return migration following prolonged forced internal displacement on mental health. Also, the role of resilience factors remains to be clarified following situations of prolonged displacement. The public health impact of internal displacement is not clearly understood. Epidemiological and interventional research in IDP mental health needs to look beyond medicalised models and encompass broader social and cultural aspects. The resilience factor should be integrated and explored more in mental health research among IDP and a clearly focused multidisciplinary approach is advocated.

Cadmium exposure and risk of prostate cancer: a meta-analysis of cohort and case-control studies among the general and occupational populations

PubMed Central

Chen, Cheng; Xun, Pengcheng; Nishijo, Muneko; Carter, Sue; He, Ka

2016-01-01

We aimed to evaluate the association of cadmium exposure with the risk of prostate cancer in both the general and occupational populations. Online database searches were performed for studies of prostate cancer risk and cadmium exposure. Twelve cohort studies (5 in the general, 7 in occupational populations) and 9 case-control studies (3 in the general, 6 in occupational populations) were identified. Five/seven cohort studies in the general and occupational populations consist of 78,263/13, 434 participants with a mean follow-up of 12.1/43.0 years, respectively. Case-control studies include 334 cases/670 controls in the general population, and 1,315 cases/4,477 controls in occupational populations. Comparing the highest to the lowest category of cadmium exposure in the general population, the weighted relative risk of prostate cancer incidence and mortality among cohort studies, and the weighted odds ratio in case-control studies were 1.05 (95%CI [0.91, 1.22]), 0.83 (95%CI [0.35, 1.98]), and 1.27 (95%CI [0.58,2.78]), respectively. For occupational populations, the weighted OR in case-control studies was 1.17 (95%CI [0.85, 1.62]), and the weighted standardized mortality ratio in cohort studies was 98 (95%CI [75, 126]). Accumulated epidemiological evidence does not support the hypothesis that cadmium exposure may increase the risk of prostate cancer in either the general or occupational populations. PMID:27174617

Cadmium exposure and risk of prostate cancer: a meta-analysis of cohort and case-control studies among the general and occupational populations.

PubMed

Chen, Cheng; Xun, Pengcheng; Nishijo, Muneko; Carter, Sue; He, Ka

2016-05-13

We aimed to evaluate the association of cadmium exposure with the risk of prostate cancer in both the general and occupational populations. Online database searches were performed for studies of prostate cancer risk and cadmium exposure. Twelve cohort studies (5 in the general, 7 in occupational populations) and 9 case-control studies (3 in the general, 6 in occupational populations) were identified. Five/seven cohort studies in the general and occupational populations consist of 78,263/13, 434 participants with a mean follow-up of 12.1/43.0 years, respectively. Case-control studies include 334 cases/670 controls in the general population, and 1,315 cases/4,477 controls in occupational populations. Comparing the highest to the lowest category of cadmium exposure in the general population, the weighted relative risk of prostate cancer incidence and mortality among cohort studies, and the weighted odds ratio in case-control studies were 1.05 (95%CI [0.91, 1.22]), 0.83 (95%CI [0.35, 1.98]), and 1.27 (95%CI [0.58,2.78]), respectively. For occupational populations, the weighted OR in case-control studies was 1.17 (95%CI [0.85, 1.62]), and the weighted standardized mortality ratio in cohort studies was 98 (95%CI [75, 126]). Accumulated epidemiological evidence does not support the hypothesis that cadmium exposure may increase the risk of prostate cancer in either the general or occupational populations.

New Rodent Population Models May Inform Human Health Risk Assessment and Identification of Genetic Susceptibility to Environmental Exposures

PubMed Central

Harrill, Alison H.

2017-01-01

Background: This paper provides an introduction for environmental health scientists to emerging population-based rodent resources. Mouse reference populations provide an opportunity to model environmental exposures and gene–environment interactions in human disease and to inform human health risk assessment. Objectives: This review will describe several mouse populations for toxicity assessment, including older models such as the Mouse Diversity Panel (MDP), and newer models that include the Collaborative Cross (CC) and Diversity Outbred (DO) models. Methods: This review will outline the features of the MDP, CC, and DO mouse models and will discuss published case studies investigating the use of these mouse population resources in each step of the risk assessment paradigm. Discussion: These unique resources have the potential to be powerful tools for generating hypotheses related to gene–environment interplay in human disease, performing controlled exposure studies to understand the differential responses in humans for susceptibility or resistance to environmental exposures, and identifying gene variants that influence sensitivity to toxicity and disease states. Conclusions: These new resources offer substantial advances to classical toxicity testing paradigms by including genetically sensitive individuals that may inform toxicity risks for sensitive subpopulations. Both in vivo and complementary in vitro resources provide platforms with which to reduce uncertainty by providing population-level data around biological variability. https://doi.org/10.1289/EHP1274 PMID:28886592

Efficacy of smoking cessation therapy alone or integrated with prolonged exposure therapy for smokers with PTSD: Study protocol for a randomized controlled trial.

PubMed

Powers, Mark B; Kauffman, Brooke Y; Kleinsasser, Anne L; Lee-Furman, Eunjung; Smits, Jasper A J; Zvolensky, Michael J; Rosenfield, David

2016-09-01

Posttraumatic stress disorder (PTSD) is related to an increased risk of smoking cessation failure. In fact, the quit rate in smokers with PTSD (23.2%) is one of the lowest of all mental disorders. Features of PTSD that contribute to smokers' progression to nicotine dependence and cessation relapse include negative affect, fear, increased arousal, irritability, anger, distress intolerance, and anxiety sensitivity. Anxiety sensitivity is higher in people with PTSD than in any other anxiety disorder except for panic disorder. High anxiety sensitivity is uniquely associated with greater odds of lapse and relapse during quit attempts. Distress intolerance, a perceived or behavioral tendency to not tolerate distress, is related to both the maintenance of PTSD and problems in quitting smoking. Prolonged exposure (PE) and interoceptive exposure (IE) reduce PTSD symptoms, distress intolerance, and anxiety sensitivity. Thus, they emerge as promising candidates to augment standard smoking cessation interventions for individuals with PTSD. The present study tests a 12-session specialized treatment for smokers with PTSD. This Integrated PTSD and Smoking Treatment (IPST) combines cognitive-behavioral therapy and nicotine replacement treatment for smoking cessation (standard care; SC) with PE to target PTSD symptoms and IE to reduce anxiety sensitivity and distress intolerance. Adult smokers (N=80) with PTSD will be randomly assigned to either: (1) IPST or (2) SC. Primary outcomes are assessed at weeks 0, 6, 8, 10, 14, 16, 22, and 30. Copyright © 2016. Published by Elsevier Inc.

Breast cancer risk from low-dose exposures to ionizing radiation: results of parallel analysis of three exposed populations of women

DOE Office of Scientific and Technical Information (OSTI.GOV)

Land, C.E.; Boice, J.D. Jr.; Shore, R.E.

1980-08-01

Breast cancer incidence data were analyzed from three populations of women exposed to ionizing radiation: survivors of the Hiroshima and Nagasaki atomic bombs, patients in Massachusetts tuberculosis sanitoria who were exposed to multiple chest fluoroscopies, and patients treated by X-rays for acute postpartum mastitis in Rochester, New York. Parallel analyses by radiation dose, age at exposure, and time after exposure suggested that risk of radiation-induced cancer increased approximately linearly with increasing dose and was heavily dependent on age at exposure; however, the risk was otherwise remarkably similar among the three populations, at least for ages 10 to 40 years atmore » exposure, and followed the same temporal pattern of occurrence as did breast cancer incidence in nonexposed women of similar ages.« less

Bone Resorption and Environmental Exposure to Cadmium in Women: A Population Study

PubMed Central

Schutte, Rudolph; Nawrot, Tim S.; Richart, Tom; Thijs, Lutgarde; Vanderschueren, Dirk; Kuznetsova, Tatiana; Van Hecke, Etienne; Roels, Harry A.; Staessen, Jan A.

2008-01-01

Background Environmental exposure to cadmium decreases bone density indirectly through hypercalciuria resulting from renal tubular dysfunction. Objective We sought evidence for a direct osteotoxic effect of cadmium in women. Methods We randomly recruited 294 women (mean age, 49.2 years) from a Flemish population with environmental cadmium exposure. We measured 24-hr urinary cadmium and blood cadmium as indexes of lifetime and recent exposure, respectively. We assessed the multivariate-adjusted association of exposure with specific markers of bone resorption, urinary hydroxylysylpyridinoline (HP) and lysylpyridinoline (LP), as well as with calcium excretion, various calciotropic hormones, and forearm bone density. Results In all women, the effect sizes associated with a doubling of lifetime exposure were 8.4% (p = 0.009) for HP, 6.9% (p = 0.10) for LP, 0.77 mmol/day (p = 0.003) for urinary calcium, –0.009 g/cm2 (p = 0.055) for proximal forearm bone density, and –16.8% (p = 0.065) for serum parathyroid hormone. In 144 postmenopausal women, the corresponding effect sizes were –0.01223 g/cm2 (p = 0.008) for distal forearm bone density, 4.7% (p = 0.064) for serum calcitonin, and 10.2% for bone-specific alkaline phosphatase. In all women, the effect sizes associated with a doubling of recent exposure were 7.2% (p = 0.001) for urinary HP, 7.2% (p = 0.021) for urinary LP, –9.0% (p = 0.097) for serum parathyroid hormone, and 5.5% (p = 0.008) for serum calcitonin. Only one woman had renal tubular dysfunction (urinary retinol-binding protein > 338 μg/day). Conclusions In the absence of renal tubular dysfunction, environmental exposure to cadmium increases bone resorption in women, suggesting a direct osteotoxic effect with increased calciuria and reactive changes in calciotropic hormones. PMID:18560534

The role of nitric oxide synthase in reduced vasocontractile responsiveness induced by prolonged α1-adrenergic receptor stimulation in rat thoracic aorta

PubMed Central

Gürdal, Hakan; Can, Alp; Uğur, Mehmet

2005-01-01

Prolonged exposure (6–12 h) of rat aorta to alpha1-adrenergic receptor (α1AR) agonist phenylephrine (Phe) leads to a decrease in α1AR-mediated vasoconstriction. This reduced responsiveness to α1AR stimulation was strongly dependent on the intactness of the endothelium. We examined the effect of Phe on nitric oxide synthase (NOS) activity by measuring the conversion of [3H]L-arginine to [3H]L-citrulline in rat aorta or in endothelial cells isolated from rat aorta. Phe stimulation increased NOS activity in control aortas. This response was antagonized by prazosin. However, Phe increased neither the activity of NOS nor intracellular Ca2+ in the isolated endothelial cells from the control aortas, whereas acetylcholine (Ach) was able to stimulate both responses in these cells. This result suggests that Phe stimulates α1AR on vascular smooth muscle cells and has an indirect influence on endothelial cells to increase NOS activity. In Phe-exposed aortic rings, basal NOS activity was found to have increased compared to vehicle-exposed control rings. Stimulation with Phe or Ach caused a small increase over basal NOS activity in these preparations. Prolonged exposure to Phe also caused an enhancement of Ach-mediated vasorelaxation in rat aorta. Immunoblot and reverse transcription–polymerase chain reaction experiments showed that prolonged exposure of rat aorta to Phe resulted in an increased expression of eNOS, but not iNOS. This increase was antagonized by nonselective antagonist prazosin. Immunohistochemical staining experiments also showed that expression of eNOS increased in endothelial cells after Phe exposure of the aortas. These results, all together, showed that prolonged exposure of rat aorta to α1AR agonist Phe enhanced the expression of eNOS and basal NOS activity, which probably causes a decreased vasocontractile response to Phe or to other agonists such as 5HT (5-hydroxytryptamine) in rat aorta. This phenomenon can be considered more as a functional

Prolonged menstrual cycles in female workers exposed to ethylene glycol ethers in the semiconductor manufacturing industry.

PubMed

Hsieh, G-Y; Wang, J-D; Cheng, T-J; Chen, P-C

2005-08-01

It has been shown that female workers exposed to ethylene glycol ethers (EGEs) in the semiconductor industry have higher risks of spontaneous abortion, subfertility, and menstrual disturbances, and prolonged waiting time to pregnancy. To examine whether EGEs or other chemicals are associated with long menstrual cycles in female workers in the semiconductor manufacturing industry. Cross-sectional questionnaire survey during the annual health examination at a wafer manufacturing company in Taiwan in 1997. A three tiered exposure-assessment strategy was used to analyse the risk. A short menstrual cycle was defined to be a cycle less than 24 days and a long cycle to be more than 35 days. There were 606 valid questionnaires from 473 workers in fabrication jobs and 133 in non-fabrication areas. Long menstrual cycles were associated with workers in fabrication areas compared to those in non-fabrication areas. Using workers in non-fabrication areas as referents, workers in photolithography and diffusion areas had higher risks for long menstrual cycles. Workers exposed to EGEs and isopropanol, and hydrofluoric acid, isopropanol, and phosphorous compounds also showed increased risks of a long menstrual cycle. Exposure to multiple chemicals, including EGEs in photolithography, might be associated with long menstrual cycles, and may play an important role in a prolonged time to pregnancy in the wafer manufacturing industry; however, the prevalence in the design, possible exposure misclassification, and chance should be considered.

Comparing Virtual Reality Exposure Therapy to Prolonged Exposure in the Treatment of Soldiers with PTSD

DTIC Science & Technology

2014-06-01

Type I alpha should be discussed in relation to the findings for multiple primary hypothesis tests conducted . o The hypotheses indicated in the...memory during exposure. However, there is limited research on the effectiveness of either treatment with active duty military personnel and there are...VRE or were assigned to a minimal attention wait list. All assessments were conducted by a psychologist blind to treatment group. External

Comparison in waterborne Cu, Ni and Pb bioaccumulation kinetics between different gammarid species and populations: Natural variability and influence of metal exposure history.

PubMed

Urien, N; Farfarana, A; Uher, E; Fechner, L C; Chaumot, A; Geffard, O; Lebrun, J D

2017-12-01

Kinetic parameters (uptake from solution and elimination rate constants) of Cu, Ni and Pb bioaccumulation were determined from two Gammarus pulex and three Gammarus fossrum wild populations collected from reference sites throughout France in order to assess the inter-species and the natural inter-population variability of metal bioaccumulation kinetics in that sentinel organism. For that, each population was independently exposed for seven days to either 2.5μgL -1 Cu (39.3nM), 40μgL -1 Ni (681nM) or 10μgL -1 Pb (48.3nM) in laboratory controlled conditions, and then placed in unexposed microcosms for a 7-day depuration period. In the same way, the possible influence of metal exposure history on subsequent metal bioaccumulation kinetics was addressed by collecting wild gammarids from three populations inhabiting stations contaminated either by Cd, Pb or both Pb and Ni (named pre-exposed thereafter). In these pre-exposed organisms, assessment of any changes in metal bioaccumulation kinetics was achieved by comparison with the natural variability of kinetic parameters defined from reference populations. Results showed that in all studied populations (reference and pre-exposed) no significant Cu bioaccumulation was observed at the exposure concentration of 2.5μgL -1 . Concerning the reference populations, no significant differences in Ni and Pb bioaccumulation kinetics between the two species (G. pulex and G. fossarum) was observed allowing us to consider all the five reference populations to determine the inter-population natural variability, which was found to be relatively low (kinetic parameters determined for each population remained within a factor of 2 of the minimum and maximum values). Organisms from the population exhibiting a Pb exposure history presented reduced Ni uptake and elimination rate constants, whereas no influence on Ni kinetic parameters was observed in organisms from the population exhibiting an exposure history to both Ni and Pb. Furthermore

[Brain function recovery after prolonged posttraumatic coma].

PubMed

Klimash, A V; Zhanaidarov, Z S

2016-01-01

To explore the characteristics of brain function recovery in patients after prolonged posttraumatic coma and with long-unconscious states. Eighty-seven patients after prolonged posttraumatic coma were followed-up for two years. An analysis of a clinical/neurological picture after a prolonged episode of coma was based on the dynamics of vital functions, neurological status and patient's reactions to external stimuli. Based on the dynamics of the clinical/neurological picture that shows the recovery of functions of the certain brain areas, three stages of brain function recovery after a prolonged episode of coma were singled out: brain stem areas, diencephalic areas and telencephalic areas. These functional/anatomic areas of brain function recovery after prolonged coma were compared to the present classifications.

Poultry Consumption and Arsenic Exposure in the U.S. Population.

PubMed

Nigra, Anne E; Nachman, Keeve E; Love, David C; Grau-Perez, Maria; Navas-Acien, Ana

2017-03-01

Arsenicals (roxarsone and nitarsone) used in poultry production likely increase inorganic arsenic (iAs), monomethylarsonic acid (MMA), dimethylarsinic acid (DMA), and roxarsone or nitarsone concentrations in poultry meat. However, the association between poultry intake and exposure to these arsenic species, as reflected in elevated urinary arsenic concentrations, is unknown. Our aim was to evaluate the association between 24-hr dietary recall of poultry consumption and arsenic exposure in the U.S. population. We hypothesized first, that poultry intake would be associated with higher urine arsenic concentrations and second, that the association between turkey intake and increased urine arsenic concentrations would be modified by season, reflecting seasonal use of nitarsone. We evaluated 3,329 participants ≥ 6 years old from the 2003-2010 National Health and Nutrition Examination Survey (NHANES) with urine arsenic available and undetectable urine arsenobetaine levels. Geometric mean ratios (GMR) of urine total arsenic and DMA were compared across increasing levels of poultry intake. After adjustment, participants in the highest quartile of poultry consumption had urine total arsenic 1.12 (95% CI: 1.04, 1.22) and DMA 1.13 (95% CI: 1.06, 1.20) times higher than nonconsumers. During the fall/winter, participants in the highest quartile of turkey intake had urine total arsenic and DMA 1.17 (95% CI: 0.99, 1.39; p -trend = 0.02) and 1.13 (95% CI: 0.99, 1.30; p -trend = 0.03) times higher, respectively, than nonconsumers. Consumption of turkey during the past 24 hr was not associated with total arsenic or DMA during the spring/summer. Poultry intake was associated with increased urine total arsenic and DMA in NHANES 2003-2010, reflecting arsenic exposure. Seasonally stratified analyses by poultry type provide strong suggestive evidence that the historical use of arsenic-based poultry drugs contributed to arsenic exposure in the U.S. Nigra AE, Nachman KE, Love DC, Grau

[Pathophysiology of prolonged hypokinesia].

PubMed

Kovalenko, E A

1976-01-01

Hypokinesia is an important problem in modern medicine. In the pathogenetic effect of prolonged hypokinesia the main etiological factor is diminished motor activity; of major importance are disorders in the energy and plastic metabolism which affect the muscle system; the contributing factors are cardiovascular deconditioning and orthostatic intolerance. This is attributed to a decreased oxygen supply and eliminated hydrostatic influences during a prolonged recumbency. Blood redistribution in the vascular bed is related to the Gauer-Henry reflex and subsequent changes in the fluid-electrolyte balance. Decreased load on the bone system induces changes in the protein-phosphate-calcium metabolism, diminished bone density and increased calcium content in the blood and urine. Changes in the calcium metabolism are systemic. The activity of the higher nervous system and reflex functions is lowered. Changes in the function of the autonomic nervous system which include a noticeable decline of its adaptive-trophic role as a result of the decrease of afferent and efferent impulsation are of great importance. Changes in the hormonal function involve a peculiar stress-reaction which develops at an early stage of hypokinesia as a response to an unusual situation. Prolonged hypokinesia may result in a disturbed function of the pituitary-adrenal system. It is assumed that prolonged hypokinesia may induce a specific disease of hypokinesia during which man cannot lead a normal mode of life and work.

Myopia and Exposure to Organophosphate and Pyrethroid Pesticides in the General United States Population.

PubMed

Migneron-Foisy, Vincent; Bouchard, Maryse F; Freeman, Ellen E; Saint-Amour, Dave

2017-09-01

Previous research suggests that exposure to pesticides might be associated with human myopia, although data were obtained only from highly exposed individuals. The present study aimed to assess whether exposure to organophosphates and pyrethroids in the United States general population was associated with the prevalence of myopia. Data were obtained from the National Health and Nutrition Examination Survey (NHANES, years 1999-2008). One-spot urine samples were used to estimate the concentration of several pesticide metabolites. Exposure data and equivalent spherical refraction errors were available for 5147 and 2911 individuals for organophosphates and pyrethroids, respectively. Multiple logistic regression models were used to assess the relation between log10-transformed urinary levels of pesticide metabolites and the risk of moderate (≤-1 and >-5 diopters [D]) and high myopia (≤-5 D) in adolescents (12- to 19-years old) and young adults (20- to 40-years old). Models were adjusted for sex, age, ethnicity, diabetes, creatinine, cadmium and lead concentrations, and income in both age groups, but also for education level and cigarette and alcohol consumption in the adult group. No association between organophosphates or pyrethroid metabolites and myopia was observed. However, after adjusting for education level and cigarette and alcohol consumption, a statistically significant decreased risk of high myopia in those with a 10-fold increase of dialkyl phosphate metabolites was found in adults but only in men (P < 0.05). Our results suggest that exposure to organophosphates or pyrethroids do not increase the risk of myopia in the United States general population.

Exposure to mercury in susceptible population groups living in the former mercury mining town of Idrija, Slovenia.

PubMed

Kobal, Alfred B; Snoj Tratnik, Janja; Mazej, Darja; Fajon, Vesna; Gibičar, Darija; Miklavčič, Ana; Kocman, David; Kotnik, Jože; Sešek Briški, Alenka; Osredkar, Joško; Krsnik, Mladen; Prezelj, Marija; Knap, Črtomir; Križaj, Bojana; Liang, Lian; Horvat, Milena

2017-01-01

500 years of mercury (Hg) mining in the town of Idrija has caused severe pollution in Idrija and its surroundings. Following the closure of the mine in 1995, the environment remains contaminated with Hg. Sources of elemental-, inorganic- and methyl Hg exposure were identified, potential environmental level of exposure to Hg was evaluated and actual internal exposure to Hg was assessed in selected susceptible population groups comprising school-age children and pregnant women living in Idrija and in control groups from rural and urban environments. The study of pregnant women (n=31) was conducted between 2003 and 2008, and the study of school-age children (n=176) in 2008. Potential interaction of Hg with selenium (Se) in plasma was assessed in both study populations, while in pregnant women antioxidative enzyme activity (glutathione peroxidase, superoxide dismutase and catalase) in erythrocytes of maternal and cord blood was also assessed. Actual exposure to Hg as indicated by levels of Hg in children's blood (geometric mean (GM) 0.92µg/L), mother's blood (GM 1.86µg/L), children's urine (GM 1.08µg/g crea.), mother's urine (GM 2.51µg/L), children's hair (GM 241ng/g) and mother's hair (GM 251ng/g) was higher in the two study groups from Idrija than in the control groups from rural areas, but was still at the level of a "normal" population and reflects mainly exposure to elemental Hg (Hg°) from dental amalgam and, to a certain extent atmospheric Hg°. Furthermore, the internal doses of Hg received during pregnancy did not decrease the bioavailability of Se. Based on observation in children, the increase in Se protein expression is suggested to be a consequence of moderately elevated exposure to Hg°. The observed changes in activity of antioxidative enzymes, as biomarkers of oxidative stress, appear to be mainly associated with pregnancy per se and not with an increased exposure to Hg. In view of the continuing increased potential for Hg exposure and the low

Mercury risk assessment combining internal and external exposure methods for a population living near a municipal solid waste incinerator.

PubMed

Deng, Chunyan; Xie, Han; Ye, Xuejie; Zhang, Haoran; Liu, Maodian; Tong, Yindong; Ou, Langbo; Yuan, Wen; Zhang, Wei; Wang, Xuejun

2016-12-01

Risk assessments for human health have been conducted for municipal solid waste incinerators (MSWIs) in many western countries, whereas only a few risk assessments have been performed for MSWIs in developing countries such as China where the use of waste incineration is increasing rapidly. To assess the mercury exposure risks of a population living near the largest MSWI in South China, we combined internal exposure and external exposure assessment with an individual-specific questionnaire. The mercury concentrations in air, soil, and locally collected food around the MSWI were assessed. The total mercury (T-Hg) and methylmercury (MeHg) of 447 blood samples from a control group, residential exposure group, and MSWI workers were measured. The internal and external exposures of the subject population were analyzed. Significant difference in MeHg concentrations was observed between the control group and the exposed group, between the control group and the MSWI workers, and between the exposed group and the MSWI workers (median levels: 0.70 μg/L, 0.81 μg/L, and 1.02 μg/L for the control group, exposed group, and MSWI workers, respectively). The MeHg/T-Hg ratio was 0.51 ± 0.19, 0.59 ± 0.17 and 0.58 ± 0.25, respectively. Multiple linear regression analysis indicated that MeHg concentrations were positively correlated with the gaseous mercury in the air. Combining internal and external exposure assessment showed that the direct contribution of MSWI emissions was minor compared with the dietary contribution. The external and internal exposures were well matched with each other. This study also suggested that an integrated method combining internal and external exposure assessment with an individual-specific questionnaire is feasible to assess the risks for a population living near a MSWI. Copyright © 2016 Elsevier Ltd. All rights reserved.

Pregnancy exposures and risk of childhood asthma admission in a population birth cohort.

PubMed

Algert, Charles S; Bowen, Jennifer R; Lain, Samantha L; Allen, Hugh D; Vivian-Taylor, Josephine M; Roberts, Christine L

2011-12-01

There is increasing interest in the potential for in utero exposures to affect the risk of asthma. We used population data to explore the associations between perinatal conditions and the risk of hospital admission with asthma between the 2nd and 5th birthday. The study population was 240,511 singleton infants born during 2001-2003. Birth records and longitudinally linked hospital admissions were used to identify asthma admissions and to model potential risk factors. A total of 7245 children (3.0%) had one or more childhood admissions with asthma. In utero infectious exposures associated with childhood asthma were maternal antenatal admission with a urinary tract infection (UTI) [adjusted odds ratio (aOR) = 1.49, 95% confidence interval (1.23-1.79)] and pre-term pre-labor rupture of membranes (PROM) [aOR = 1.23 (1.04-1.45)]. There was no evidence that gestational age at time of first antenatal UTI admission (<28, ≥ 28 wks) affected the risk of asthma (homogeneity test p = 0.6). Pre-term birth was a risk factor for asthma admission, with the risk decreasing by 5.3% with each extra week of gestation. Autumn and winter conceptions were associated with an increased risk of childhood asthma admission: winter aOR = 1.15 (1.08-1.23), autumn aOR = 1.09 (1.02-1.16). As in utero exposure to both UTI and PROM carry an increased risk of childhood asthma admission, this suggests that the immune system response generally is the relevant factor rather than a specific organism. The season-associated risk is consistent with early pregnancy exposures such as the winter flu season or low vitamin D. © 2011 John Wiley & Sons A/S.

The impact of prolonged violent video-gaming on adolescent sleep: an experimental study.

PubMed

King, Daniel L; Gradisar, Michael; Drummond, Aaron; Lovato, Nicole; Wessel, Jason; Micic, Gorica; Douglas, Paul; Delfabbro, Paul

2013-04-01

Video-gaming is an increasingly prevalent activity among children and adolescents that is known to influence several areas of emotional, cognitive and behavioural functioning. Currently there is insufficient experimental evidence about how extended video-game play may affect adolescents' sleep. The aim of this study was to investigate the short-term impact of adolescents' prolonged exposure to violent video-gaming on sleep. Seventeen male adolescents (mean age = 16 ± 1 years) with no current sleep difficulties played a novel, fast-paced, violent video-game (50 or 150 min) before their usual bedtime on two different testing nights in a sleep laboratory. Objective (polysomnography-measured sleep and heart rate) and subjective (single-night sleep diary) measures were obtained to assess the arousing effects of prolonged gaming. Compared with regular gaming, prolonged gaming produced decreases in objective sleep efficiency (by 7 ± 2%, falling below 85%) and total sleep time (by 27 ± 12 min) that was contributed by a near-moderate reduction in rapid eye movement sleep (Cohen's d = 0.48). Subjective sleep-onset latency significantly increased by 17 ± 8 min, and there was a moderate reduction in self-reported sleep quality after prolonged gaming (Cohen's d = 0.53). Heart rate did not differ significantly between video-gaming conditions during pre-sleep game-play or the sleep-onset phase. Results provide evidence that prolonged video-gaming may cause clinically significant disruption to adolescent sleep, even when sleep after video-gaming is initiated at normal bedtime. However, physiological arousal may not necessarily be the mechanism by which technology use affects sleep. © 2012 European Sleep Research Society.

Exposure-safety and efficacy response relationships and population pharmacokinetics of eslicarbazepine acetate.

PubMed

Gidal, B E; Jacobson, M P; Ben-Menachem, E; Carreño, M; Blum, D; Soares-da-Silva, P; Falcão, A; Rocha, F; Moreira, J; Grinnell, T; Ludwig, E; Fiedler-Kelly, J; Passarell, J; Sunkaraneni, S

2018-05-06

Eslicarbazepine acetate (ESL) is a once-daily (QD) oral antiepileptic drug (AED) for focal-onset seizures (FOS). Pharmacokinetic (PK) and pharmacodynamic (PD) models were developed to assess dose selection, identify significant AED drug interactions, and quantitate relationships between exposure and safety and efficacy outcomes from Phase 3 trials of adjunctive ESL. Eslicarbazepine (the primary active metabolite of ESL) population PK was evaluated using data from 1351 subjects enrolled in 14 studies (11 Phase 1 and three Phase 3 studies) after multiple oral doses ranging from 400 to 1200 mg. Population PK and PD models related individual eslicarbazepine exposures to safety outcomes and efficacy responses. Eslicarbazepine PK was described by a one-compartment model with linear absorption and elimination. The probability of a treatment-emergent adverse event (TEAE; dizziness, headache, or somnolence) was higher with an initial dose of ESL 800 mg than with an initial dose of ESL 400 mg QD. Body weight, sex, region, and baseline use of carbamazepine (CBZ) or lamotrigine were also found to influence the probability of TEAEs. Eslicarbazepine exposure influenced serum sodium concentration, standardized seizure frequency, and probability of response; better efficacy outcomes were predicted in patients not from Western Europe (WE; vs WE patients) and those not taking CBZ (vs taking CBZ) at baseline. Pharmacokinetic and PK/PD modeling were implemented during the development of ESL for adjunctive treatment of FOS in adults. This quantitative approach supported decision-making during the development of ESL, and contributed to dosing recommendations and labeling information related to drug interactions. © 2018 The Authors. Acta Neurologica Scandinavica Published by John Wiley & Sons Ltd.

Simulation of Population-Based Commuter Exposure to NO2 Using Different Air Pollution Models

PubMed Central

Ragettli, Martina S.; Tsai, Ming-Yi; Braun-Fahrländer, Charlotte; de Nazelle, Audrey; Schindler, Christian; Ineichen, Alex; Ducret-Stich, Regina E.; Perez, Laura; Probst-Hensch, Nicole; Künzli, Nino; Phuleria, Harish C.

2014-01-01

We simulated commuter routes and long-term exposure to traffic-related air pollution during commute in a representative population sample in Basel (Switzerland), and evaluated three air pollution models with different spatial resolution for estimating commute exposures to nitrogen dioxide (NO2) as a marker of long-term exposure to traffic-related air pollution. Our approach includes spatially and temporally resolved data on actual commuter routes, travel modes and three air pollution models. Annual mean NO2 commuter exposures were similar between models. However, we found more within-city and within-subject variability in annual mean (±SD) NO2 commuter exposure with a high resolution dispersion model (40 ± 7 µg m−3, range: 21–61) than with a dispersion model with a lower resolution (39 ± 5 µg m−3; range: 24–51), and a land use regression model (41 ± 5 µg m−3; range: 24–54). Highest median cumulative exposures were calculated along motorized transport and bicycle routes, and the lowest for walking. For estimating commuter exposure within a city and being interested also in small-scale variability between roads, a model with a high resolution is recommended. For larger scale epidemiological health assessment studies, models with a coarser spatial resolution are likely sufficient, especially when study areas include suburban and rural areas. PMID:24823664

THE RELATIONSHIPS BETWEEN PERSONAL PM EXPOSURES FOR ELDERLY POPULATIONS AND INDOOR AND OUTDOOR CONCENTRATIONS FOR THREE RETIREMENT CENTER SCENARIOS

EPA Science Inventory

Personal exposure, indoor and outdoor concentration, "physical factor", and questionnaire data were collected in three retirement center settings, supporting broader PM-health studies of elderly populations. The studies varied geographically and temporally, with popul...

Adaptive prolonged postreproductive life span in killer whales.

PubMed

Foster, Emma A; Franks, Daniel W; Mazzi, Sonia; Darden, Safi K; Balcomb, Ken C; Ford, John K B; Croft, Darren P

2012-09-14

Prolonged life after reproduction is difficult to explain evolutionarily unless it arises as a physiological side effect of increased longevity or it benefits related individuals (i.e., increases inclusive fitness). There is little evidence that postreproductive life spans are adaptive in nonhuman animals. By using multigenerational records for two killer whale (Orcinus orca) populations in which females can live for decades after their final parturition, we show that postreproductive mothers increase the survival of offspring, particularly their older male offspring. This finding may explain why female killer whales have evolved the longest postreproductive life span of all nonhuman animals.

THE RELATIONSHIPS BETWEEN PERSONAL PM EXPOSURES FOR ELDERLY POPULATIONS AND INDOOR AND OUTDOOR CONCENTRATIONS FOR THREE RETIREMENT CENTER SCENARIOS

EPA Science Inventory

Personal exposures, indoor and outdoor concentrations, and questionnaire data were collected in three retirement center settings, supporting broader PM-health studies of elderly populations. The studies varied geographically and temporally, with populations studied in Baltimor...

AN ESTIMATION OF THE EXPOSURE OF THE POPULATION OF ISRAEL TO NATURAL SOURCES OF IONIZING RADIATION.

PubMed

Epstein, L; Koch, J; Riemer, T; Haquin, G; Orion, I

2017-11-01

The radiation dose to the population of Israel due to exposure to natural sources of ionizing radiation was assessed. The main contributor to the dose is radon that accounts for 60% of the exposure to natural sources. The dose due to radon inhalation was assessed by combining the results of a radon survey in single-family houses with the results of a survey in apartments in multi-storey buildings. The average annual dose due to radon inhalation was found to be 1.2 mSv. The dose rate due to exposure to cosmic radiation was assessed using a code that calculates the dose rate at different heights above sea level, taking into account the solar cycle. The annual dose was calculated based on the fraction of time spent indoors and the attenuation provided by buildings and was found to be 0.2 mSv. The annual dose due to external exposure to the terrestrial radionuclides was similarly assessed. The indoor dose rate was calculated using a model that takes into account the concentrations of the natural radionuclides in building materials, the density and the thickness of the walls. The dose rate outdoors was calculated based on the concentrations of the natural radionuclides in different geological units in Israel as measured in an aerial survey and measurements above ground. The annual dose was found to be 0.2 mSv. Doses due to internal exposure other than exposure to radon were also calculated and were found to be 0.4 mSv. The overall annual exposure of the population of Israel to natural sources of ionizing radiation is therefore 2 mSv and ranges between 1.7 and 2.7 mSv. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Clinical dysphagia risk predictors after prolonged orotracheal intubation

PubMed Central

de Medeiros, Gisele Chagas; Sassi, Fernanda Chiarion; Mangilli, Laura Davison; Zilberstein, Bruno; de Andrade, Claudia Regina Furquim

2014-01-01

OBJECTIVES: To elucidate independent risk factors for dysphagia after prolonged orotracheal intubation. METHODS: The participants were 148 consecutive patients who underwent clinical bedside swallowing assessments from September 2009 to September 2011. All patients had received prolonged orotracheal intubations and were admitted to one of several intensive care units of a large Brazilian school hospital. The correlations between the conducted water swallow test results and dysphagia risk levels were analyzed for statistical significance. RESULTS: Of the 148 patients included in the study, 91 were male and 57 were female (mean age, 53.64 years). The univariate analysis results indicated that specific variables, including extraoral loss, multiple swallows, cervical auscultation, vocal quality, cough, choking, and other signs, were possible significant high-risk indicators of dysphagia onset. The multivariate analysis results indicated that cervical auscultation and coughing were independent predictive variables for high dysphagia risk. CONCLUSIONS: Patients displaying extraoral loss, multiple swallows, cervical auscultation, vocal quality, cough, choking and other signs should benefit from early swallowing evaluations. Additionally, early post-extubation dysfunction recognition is paramount in reducing the morbidity rate in this high-risk population. PMID:24473554

Incidence of nephrolithiasis in relation to environmental exposure to lead and cadmium in a population study.

PubMed

Hara, Azusa; Yang, Wen-Yi; Petit, Thibault; Zhang, Zhen-Yu; Gu, Yu-Mei; Wei, Fang-Fei; Jacobs, Lotte; Odili, Augustine N; Thijs, Lutgarde; Nawrot, Tim S; Staessen, Jan A

2016-02-01

Whether environmental exposure to nephrotoxic agents that potentially interfere with calcium homeostasis, such as lead and cadmium, contribute to the incidence of nephrolithiasis needs further clarification. We investigated the relation between nephrolithiasis incidence and environmental lead and cadmium exposure in a general population. In 1302 participants randomly recruited from a Flemish population (50.9% women; mean age, 47.9 years), we obtained baseline measurements (1985-2005) of blood lead (BPb), blood cadmium (BCd), 24-h urinary cadmium (UCd) and covariables. We monitored the incidence of kidney stones until October 6, 2014. We used Cox regression to calculate multivariable-adjusted hazard ratios for nephrolithiasis. At baseline, geometric mean BPb, BCd and UCd was 0.29µmol/L, 9.0nmol/L, and 8.5nmol per 24h, respectively. Over 11.5 years (median), nephrolithiasis occurred in 40 people. Contrasting the low and top tertiles of the distributions, the sex- and age-standardized rates of nephrolithiasis expressed as events per 1000 person-years were 0.68 vs. 3.36 (p=0.0016) for BPb, 1.80 vs. 3.28 (p=0.11) for BCd, and 1.65 vs. 2.95 (p=0.28) for UCd. In continuous analysis, with adjustments applied for sex, age, serum magnesium, and 24-h urinary volume and calcium, the hazard ratios expressing the risk associated with a doubling of the exposure biomarkers were 1.35 (p=0.015) for BPb, 1.13 (p=0.22) for BCd, and 1.23 (p=0.070) for UCd. In conclusion, our results suggest that environmental lead exposure is a risk factor for nephrolithiasis in the general population. Copyright © 2015 Elsevier Inc. All rights reserved.

Biomonitoring of organophosphate exposure of pesticide sprayers and comparison of exposure levels with other population groups in Thessaly (Greece).

PubMed

Koureas, Michalis; Tsakalof, Andreas; Tzatzarakis, Manolis; Vakonaki, Elena; Tsatsakis, Aristidis; Hadjichristodoulou, Christos

2014-02-01

To evaluate the exposure of different population groups in Thessaly (Greece) to organophosphate pesticides (OPs) and investigate the dependence of exposure levels on pesticide application practices, personal protective and hygienic measures taken. For the exposure assessment, four dialkyl phosphate (DAP) metabolites of organophosphate pesticides were quantified in spot urine samples of 77 pesticide sprayers, 75 residents of the studied agricultural area non-involved in agricultural activities and 112 urban residents who served as a control group. Structured questionnaires were used to record demographic characteristics, pesticide application parameters and protective measures taken. Univariate and multivariate analysis of the obtained cross-sectional data was performed to identify potential risk factors associated with biomarker levels. It was found that total DAP median level in the sprayers' group was 24.9 μg/g creatinine (IQR: 13.0-42.1), while the rural and urban residents had significantly lower (p<0.001) levels of 11.3 μg/g creatinine (IQR: 5.3-18.7) and 11.9 μg/g creatinine (IQR: 6.3-20.3), respectively. In sprayers who had recently applied an OP pesticide (n=28), the median levels of DAP metabolites were 31.8 μg/g creatinine (IQR: 22.3-117.2). Logistic regression analysis showed that the use of full body coveralls while handling and spraying pesticides was significantly associated with lower DAP levels (OR 4.05, 95% CI 1.22 to 13.46). Also, changing clothes immediately after accidental contamination of clothing with pesticide amounts was found to be significantly associated with lower exposure levels (OR 4.04, CI 1.05 to 15.57). Our study findings confirm the increased exposure to OPs in pesticide sprayers and underline the importance of protective measures especially those that focus on dermal exposure mitigation.

Possible interethnic differences in quinidine-induced QT prolongation between healthy Caucasian and Korean subjects

PubMed Central

Shin, Jae-Gook; Kang, Won-ku; Shon, Ji-Hong; Arefayene, Million; Yoon, Young-Ran; Kim, Kyung-Ah; Kim, Doo-Il; Kim, Dong-Soo; Cho, Kwang-Hyun; Woosley, Raymond L; Flockhart, David A

2007-01-01

Aims The aim of this study was to evaluate the pharmacokinetics and pharmacodynamics of quinidine-induced QT prolongation in healthy Caucasian and Korean subjects to investigate interethnic differences in susceptibility to drug-induced arrhythmia. Methods A randomized, double-blind crossover study was conducted in 24 (12 male and 12 female) Korean and 13 (seven male and six female) Caucasian subjects. After a 20 min infusion of quinidine (4 mg kg−1) or saline, the serum concentration of quinidine and the QT interval corrected by Bazett's formula (QTc) were monitored. The dynamic data were analyzed by means of a population modelling approach using NONMEM. Results There were no statistical differences in the pharmacokinetic profiles of quinidine between ethnic groups. The QTc values in Caucasians were higher than those in Koreans at the same quinidine concentrations, especially at higher quinidine concentrations and in female subjects. According to an Emax model , the population modelling approach revealed that E0 (ms) was related to gender (408 + [34*(1 − Sex)]; 1 for male and 0 for female), ΔEmax (ms) was related to ethnicity ((136*fETHN) + Cfemale: fETHN = 1 for Koreans and 1.26 for Caucasians; Cfemale was 106 only for Caucasian females), and EC50 was estimated to be 3.13 µm. Conclusions These results suggest that Korean subjects were less sensitive to quinidine-induced QT prolongation than Caucasian subjects, and that this trend was particularly true for females. Further population-based studies are merited to characterize more completely the ethnic differences in drug-induced QT prolongation between Asians and other ethnic groups. PMID:17096683

PRKCZ methylation is associated with sunlight exposure in a North American but not a Mediterranean population.

PubMed

Aslibekyan, Stella; Dashti, Hassan S; Tanaka, Toshiko; Sha, Jin; Ferrucci, Luigi; Zhi, Degui; Bandinelli, Stefania; Borecki, Ingrid B; Absher, Devin M; Arnett, Donna K; Ordovas, Jose M

2014-11-01

Sunlight exposure has been shown to alter DNA methylation patterns across several human cell-types, including T-lymphocytes. Since epigenetic changes establish gene expression profiles, changes in DNA methylation induced by sunlight exposure warrant investigation. The purpose of this study was to assess the effects of sunlight exposure on CD4+ T-cell methylation patterns on an epigenome-wide scale in a North American population of European origin (n=991). In addition, we investigated the genetic contribution to epigenetic variation (methylQTL). We used linear regression to test the associations between methylation scores at 461,281 cytosine-phosphate-guanine (CpG) sites and sunlight exposure, followed by a genome-wide association analysis (methylQTL) to test for associations between methylation at the top CpG locus and common genetic variants, assuming an additive genetic model. We observed an epigenome-wide significant association between sunlight exposure and methylation status at cg26930596 (p=9.2×10(-8)), a CpG site located in protein kinase C zeta (PRKCZ), a gene previously shown to be entrained by light. MethylQTL analysis resulted in significant associations between cg26930596 and two intergenic single nucleotide polymorphisms on chromosome 3, rs4574216 (p=1.5×10(-10)) and rs4405858 (p=1.9×10(-9)). These common genetic variants reside downstream of WWTR1, a transcriptional co-activator of PRKCZ. Associations observed in the North American population, however, did not replicate in an independent Mediterranean cohort. Our preliminary results support the role of sunlight exposure in epigenetic processes, and lay the groundwork for future studies of the molecular link between sunlight and physiologic processes such as tumorigenesis and metabolism.

Residential and service-population exposure to multiple natural hazards in the Mount Hood region of Clackamas County, Oregon

USGS Publications Warehouse