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Sample records for acute exposure nuclear

  1. Epidemiological studies on radiation carcinogenesis in human populations following acute exposure: nuclear explosions and medical radiation

    SciTech Connect

    Fabrikant, J.I.

    1981-05-01

    The current knowledge of the carcinogenic effect of radiation in man is considered. The discussion is restricted to dose-incidence data in humans, particularly to certain of those epidemiological studies of human populations that are used most frequently for risk estimation for low-dose radiation carcinogenesis in man. Emphasis is placed solely on those surveys concerned with nuclear explosions and medical exposures. (ACR)

  2. Cellular distribution of uranium after acute exposure of renal epithelial cells: SEM, TEM and nuclear microscopy analysis

    NASA Astrophysics Data System (ADS)

    Carrière, Marie; Gouget, Barbara; Gallien, Jean-Paul; Avoscan, Laure; Gobin, Renée; Verbavatz, Jean-Marc; Khodja, Hicham

    2005-04-01

    The major health effect of uranium exposure has been reported to be chemical kidney toxicity, functional and histological damages being mainly observed in proximal tubule cells. Uranium enters the proximal tubule as uranyl-bicarbonate or uranyl-citrate complexes. The aim of our research is to investigate the mechanisms of uranium toxicity, intracellular accumulation and repartition after acute intoxication of rat renal proximal tubule epithelial cells, as a function of its chemical form. Microscopic observations of renal epithelial cells after acute exposure to uranyl-bicarbonate showing the presence of intracellular precipitates as thin needles of uranyl-phosphate localized in cell lysosomes have been published. However the initial site of precipitates formation has not been identified yet: they could either be formed outside the cells before internalization, or directly inside the cells. Uranium solubility as a function and initial concentration was specified by ICP-MS analysis of culture media. In parallel, uranium uptake and distribution in cell monolayers exposed to U-bicarbonate was investigated by nuclear microprobe analyses. Finally, the presence of uranium precipitates was tested out by scanning electron microscopic observations (SEM), while extracellular and/or intracellular precipitates were observed on thin sections of cells by transmission electron microscopy (TEM).

  3. Epidemiological studies on radiation carcinogenesis in human populations following acute exposure: nuclear explosions and medical radiation

    SciTech Connect

    Fabrikant, J.I.

    1982-08-01

    The present review provides an understanding of our current knowledge of the carcinogenic effect of low-dose radiation in man, and surveys the epidemiological studies of human populations exposed to nuclear explosions and medical radiation. Discussion centers on the contributions of quantitative epidemiology to present knowledge, the reliability of the dose-incidence data, and those relevant epidemiological studies that provide the most useful information for risk estimation of cancer-induction in man. Reference is made to dose-incidence relationships from laboratory animal experiments where they may obtain for problems and difficulties in extrapolation from data obtained at high doses to low doses, and from animal data to the human situation. The paper describes the methods of application of such epidemiological data for estimation of excess risk of radiation-induced cancer in exposed human populations, and discusses the strengths and limitations of epidemiology in guiding radiation protection philosophy and public health policy.

  4. An acute exposure to glyphosate-based herbicide alters aromatase levels in testis and sperm nuclear quality.

    PubMed

    Cassault-Meyer, Estelle; Gress, Steeve; Séralini, Gilles-Éric; Galeraud-Denis, Isabelle

    2014-07-01

    Roundup is the major pesticide used in agriculture worldwide; it is a glyphosate-based herbicide. Its molecular effects are studied following an acute exposure (0.5%) of fifteen 60-day-old male rats during an 8-day period. Endocrine (aromatase, estrogen and androgen receptors, Gper1 in testicular and sperm mRNAs) and testicular functions (organ weights, sperm parameters and expression of the blood-testis barrier markers) were monitored at days 68, 87, and 122 after treatment, spermiogenesis and spermatogenesis. The major disruption is an increase of aromatase mRNA levels at least by 50% in treated rats at all times, as well as the aromatase protein. We have also shown a similar increase of Gper1 expression at day 122 and a light modification of BTB markers. A rise of abnormal sperm morphology and a decrease of the expression of protamine 1 and histone 1 testicular in epididymal sperm are observed despite a normal sperm concentration and motility.

  5. Acute exposure to a quinalphos containing insecticide (convoy) causes genetic damage and nuclear changes in peripheral erythrocytes of silver barb, Barbonymus gonionotus.

    PubMed

    Sadiqul, Islam M; Ferdous, Zannatul; Nannu, Md Tanvir Ahmed; Mostakim, Golam Mohammod; Rahman, Md Khalilur

    2016-12-01

    The present study was aimed to assess the genotoxic effect in fish caused by convoy, an insecticide commercial formulation containing quinalphos, present in the aquatic waterbody. For this purpose a freshwater teleost, silver barb was exposed to sublethal concentrations (25% and 50% of LC50) of convoy and erythrocytic cellular abnormalities (ECA) and erythrocytic nuclear abnormalities (ENA) tests were performed in addition to the commonly used micronucleus (MN) assay using peripheral erythrocytes and DNA contents in the different tissues after 1, 24, 36, 48, and 72 h of exposures. The obtained results indicated that acute exposure of different sub lethal concentrations of convoy to the fish resulted in significant alterations of erythrocytes as well as significant reduction of DNA contents in blood and vital organs and tissues, such as the brain, liver, kidney and muscle. Compared to each treatment excluding control group, frequencies of ECA, ENA, and MN were found to be elevated with exposure time of the doses. From this study, we conclude that convoy is a hazardous chemical to silver barb. Bioassays can be used as a tool for screening aquatic pollution, especially for insecticides. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Effect of acute exposure to cadmium on the expression of heat-shock and hormone-nuclear receptor genes in the aquatic midge Chironomus riparius.

    PubMed

    Planelló, R; Martínez-Guitarte, J L; Morcillo, G

    2010-03-01

    Cadmium is a widespread and highly toxic pollutant of particular ecotoxicological relevance for aquatic ecosystems where it accumulates. To identify biomarkers for ecotoxicity monitoring, the effect of cadmium on the expression of different genes related to the stress response as well as to the ecdysone hormone-signalling pathway was studied in the aquatic larvae of Chironomus riparius (Diptera, Chironomidae), a standard test organism in aquatic toxicology testing. Reverse Transcription Polymerase Chain Reaction (RT-PCR) was used to evaluate the effects of acute and short-term cadmium exposures (10mM CdCl(2), 12h and 24h) on the expression of hsp70, hsc70, hsp90 and hsp40 genes, as well as on that of the ecdysone hormonal-receptor genes (EcR and usp). A significant 3-fold increase in the level of hsp70 gene transcripts was induced by the treatment, whereas neither the other stress genes tested (hsp90 and hsp40) nor the constitutive form of hsp70, hsc70, was affected in the larvae exposed to cadmium. These results show that hsp70 is differentially activated to other environmentally regulated heat-shock genes, and constitutes a biomarker of exposure to this toxic metal. In addition, we also found that cadmium is able to alter the expression of the ecdysone receptor gene (EcR), whose mRNA level is significantly increased whereas usp levels remained unaltered. This finding, evidenced for the first time in invertebrates, supports the view that cadmium has the ability to mimic the effect of the hormone by the activation of the ecdysone nuclear receptor, which may partly explain the endocrine disruption capability that has been previously suggested for this toxic metal. Our research adds to the growing evidence implicating heavy metals, and cadmium in particular, as potential endocrine disruptive agents and may have significant implications for ecological risk assessment of endocrine-disrupting compounds in invertebrates.

  7. Risk of chronic myeloid and acute leukemia mortality after exposure to ionizing radiation among workers at four U.S. nuclear weapons facilities and a nuclear naval shipyard.

    PubMed

    Schubauer-Berigan, Mary K; Daniels, Robert D; Fleming, Donald A; Markey, Andrea M; Couch, James R; Ahrenholz, Steven H; Burphy, Jenneh S; Anderson, Jeri L; Tseng, Chih-Yu

    2007-02-01

    A nested case-control study was conducted among workers at five U.S. nuclear facilities to evaluate leukemia mortality risk (excluding chronic lymphocytic) from ionizing radiation using worksite doses and adjusting for potential confounding. Conditional logistic regression was used to estimate the relative risk (RR) of exposed workers and the excess relative risk (ERR) per unit of radiation among 206 cases and 823 age-matched controls. Adjusting for sex and benzene, the RR of leukemia for workers receiving more than 10 mSv was higher compared to those receiving lower or no dose; however, the risk increase was attenuated in the highest dose group. The ERR per 10 mSv was 1.44% (95% CI: < -1.03%, 7.59%) but was higher for workers born after 1921 compared to workers born earlier or when excluding leukemias of uncertain type. Excluding the 7% who were high-dose workers (> 100 mSv), the sex- and benzene-adjusted ERR per 10 mSv was 6.82% (95% CI: -2.87%, 24.1%). The results suggest that risks among these nuclear workers are comparable to those observed in high-dose populations, although no evidence was observed of a positive quadratic dose-response term in this study. This large study is among the first to jointly evaluate benzene and ionizing radiation risk.

  8. Physician knowledge of nuclear medicine radiation exposure.

    PubMed

    Riley, Paul; Liu, Hongjie; Wilson, John D

    2013-01-01

    Because physician knowledge of patient exposure to ionizing radiation from computed tomography (CT) procedures previously has been recognized as poor, the purpose of this systematic review is to determine whether physician or physician trainee knowledge of patient exposure to radiation from nuclear medicine procedures is similarly insufficient. Online databases and printed literature were systematically searched to acquire peer-reviewed published research studies involving assessment of physician or physician trainee knowledge of patient radiation exposure levels incurred during nuclear medicine and CT procedures. An a priori inclusion/exclusion criteria for study selection was used as a review protocol aimed at extracting information pertaining to participants, collection methods, comparisons within studies, outcomes, and study design. Fourteen studies from 8 countries were accepted into the review and revealed similar insufficiencies in physician knowledge of nuclear medicine and CT patient radiation exposures. Radiation exposure estimates for both modalities similarly featured a strong tendency toward physician underestimation. Discussion Comparisons were made and ratios established between physican estimates of patient radiation exposure from nuclear medicine procedures and estimates of CT procedures. A theoretical median of correct physician exposure estimates was used to examine factors affecting lower and higher estimates. The tendency for ordering physicians to underestimate patient radiation exposures from nuclear medicine and CT procedures could lead to their overuse and contribute to increasing the public's exposure to ionizing radiation.

  9. U.S. EPA'S ACUTE REFERENCE EXPOSURE METHODOLOGY FOR ACUTE INHALATION EXPOSURES

    EPA Science Inventory

    The US EPA National Center for Environmental Assessment has developed a methodology to derive acute inhalation toxicity benchmarks, called acute reference exposures (AREs), for noncancer effects. The methodology provides guidance for the derivation of chemical-specific benchmark...

  10. In Vivo Nanodetoxication for Acute Uranium Exposure.

    PubMed

    Guzmán, Luis; Durán-Lara, Esteban F; Donoso, Wendy; Nachtigall, Fabiane M; Santos, Leonardo S

    2015-06-15

    Accidental exposure to uranium is a matter of concern, as U(VI) is nephrotoxic in both human and animal models, and its toxicity is associated to chemical toxicity instead of radioactivity. We synthesized different PAMAM G4 and G5 derivatives in order to prove their interaction with uranium and their effect on the viability of red blood cells in vitro. Furthermore, we prove the effectiveness of the selected dendrimers in an animal model of acute uranium intoxication. The dendrimer PAMAM G4-Lys-Fmoc-Cbz demonstrated the ability to chelate the uranyl ion in vivo, improving the biochemical and histopathologic features caused by acute intoxication with uranium.

  11. Acute myelocytic leukemia after exposure to asbestos

    SciTech Connect

    Kishimoto, T.; Ono, T.; Okada, K.

    1988-08-15

    While the carcinogenicity of asbestos has been established in malignant mesotheliomas and lung cancers, and has recently been suspected in several other types of cancer, asbestos has not been implicated in the pathogenesis of acute leukemias. This article includes two cases of acute myelocytic leukemia in individuals with a long history of exposure to asbestos. Significant numbers of asbestos bodies were detected in specimens of their lungs and bone marrow. In addition, the kind of asbestos in both organs was crocidolite, which is implicated in carcinogenesis. No asbestos bodies were detected in the bone marrow specimens from a control group consisting of ten patients with lung cancer with similar occupational histories. The role of asbestos exposure in the development of leukemia requires further study.

  12. Acute radiation syndrome caused by accidental radiation exposure - therapeutic principles.

    PubMed

    Dörr, Harald; Meineke, Viktor

    2011-11-25

    Fortunately radiation accidents are infrequent occurrences, but since they have the potential of large scale events like the nuclear accidents of Chernobyl and Fukushima, preparatory planning of the medical management of radiation accident victims is very important. Radiation accidents can result in different types of radiation exposure for which the diagnostic and therapeutic measures, as well as the outcomes, differ. The clinical course of acute radiation syndrome depends on the absorbed radiation dose and its distribution. Multi-organ-involvement and multi-organ-failure need be taken into account. The most vulnerable organ system to radiation exposure is the hematopoietic system. In addition to hematopoietic syndrome, radiation induced damage to the skin plays an important role in diagnostics and the treatment of radiation accident victims. The most important therapeutic principles with special reference to hematopoietic syndrome and cutaneous radiation syndrome are reviewed.

  13. Pediatric nuclear medicine in acute care.

    PubMed

    Shammas, Amer; Vali, Reza; Charron, Martin

    2013-03-01

    Various radiopharmaceuticals are available for imaging pediatric patients in an acute care setting. This article focuses on the common applications used on a pediatric patient in acute care. To confirm the clinical diagnosis of brain death, brain scintigraphy is considered accurate and has been favorably compared with other methods of detecting the presence or absence of cerebral blood flow. Ventilation-perfusion lung scans are easy and safe to perform with less radiation exposure than computed tomography pulmonary angiography and remain an appropriate procedure to perform on children with suspected pulmonary embolism as a first imaging test in a hemodynamically stable patient with no history of lung disease and normal chest radiograph. (99m)Tc pertechnetate scintigraphy (Meckel's scan) is the best noninvasive procedure to establish the diagnosis of ectopic gastric mucosa in Meckel's diverticulum. Hepatobiliary scintigraphy is the most accurate diagnostic imaging modality for acute cholecystitis. (99m)Tc-dimercaptosuccinic acid scintigraphy is the simplest, and the most reliable and sensitive method for the early diagnosis of focal or diffuse functional cortical damage. Bone scintigraphy is a sensitive and noninvasive technique for the diagnosis of bone disorders such as osteomyelitis and fracture. Of recent, positron emission tomography imaging using (18)F-NaF has been introduced as an alternative to bone scintigraphy. (18)F-fluorodeoxyglucose-positron emission tomography has the potential to replace other imaging modalities, such as the evaluation of fever of unknown origin in pediatric patients, with better sensitivity and significantly less radiation exposure than gallium scan. Copyright © 2013 Elsevier Inc. All rights reserved.

  14. Regulation of nuclear radiation exposures in India.

    PubMed

    Mishra, U C

    2004-01-01

    India has a long-term program of wide spread applications of nuclear radiations and radioactive sources for peaceful applications in medicine, industry, agriculture and research and is already having several thousand places in the country where such sources are being routinely used. These places are mostly outside the Department of Atomic Energy (DAE) installations. DAE supplies such sources. The most important application of nuclear energy in DAE is in electricity generation through nuclear power plants. Fourteen such plants are operating and many new plants are at various stages of construction. In view of the above mentioned wide spread applications, Indian parliament through an Act, called Atomic Energy Act, 1964 created an autonomous body called Atomic Energy Regulatory Board (AERB) with comprehensive authority and powers. This Board issues codes, guides, manuals, etc., to regulate such installations so as to ensure safe use of such sources and personnel engaged in such installations and environment receives radiation exposures within the upper bounds prescribed by them. Periodic reports are submitted to AERB to demonstrate compliance of its directives. Health, Safety and Environment Group of Bhabha Atomic Research Centres, Mumbai carries out necessary surveillance and monitoring of all installations of the DAE on a routine basis and also periodic inspections of other installations using radiation sources. Some of the nuclear fuel cycle plants like nuclear power plants and fuel reprocessing involve large radioactive source inventories and have potential of accidental release of radioactivity into the environment, an Environmental Surveillance Laboratory (ESL) is set up at each such site much before the facility goes into operation. These ESL's collect baseline data and monitor the environment throughout the life of the facilities including the decommissioning stage. The data is provided to AERB and is available to members of the public. In addition, a multi

  15. Acute methamphetamine exposure inhibits cardiac contractile function.

    PubMed

    Turdi, Subat; Schamber, Robbie M; Roe, Nathan D; Chew, Herbert G; Culver, Bruce; Ren, Jun

    2009-09-10

    Methamphetamine, a commonly seen substance of abuse, has been reported to exert detrimental effect on bodily function including the cardiovascular system although its mechanism of action is poorly understood. This study was designed to examine the direct impact of methamphetamine on isolated whole heart and single cardiomyocyte contractile function. Murine hearts and isolated cardiomyocytes from adult FVB mice were exposed to various concentrations of methamphetamine for 30min prior to the assessment of mechanical function using a Langendroff apparatus and an IonOptix Myocam system, respectively. Cardiac contractile properties analyzed included maximal velocity of left ventricular pressure development and decline (+/-dP/dt), peak shortening amplitude (PS), maximal velocity of shortening/relengthening (+/-dLdt), time-to-PS (TPS), time-to-90% relengthening (TR(90)), resting and electrically stimulated increase of intracellular Ca(2+) as well as intracellular Ca(2+) decay. Our results revealed that acute methamphetamine exposure depressed +/-dP/dt, PS and rise of intracellular Ca(2+) without affecting +/-dLdt, TPS, TR(90), resting intracellular Ca(2+) and intracellular Ca(2+) decay. Furthermore, methamphetamine nullified the adrenergic agonist norepinephrine-elicited positive cardiomyocyte contractile response, including elevated PS, +/-dLdt and shortened TR(90) without affecting TPS. Western blot analysis showed unchanged expression of sarco(endo)plasmic reticulum Ca(2+)-ATPase (SERCA2a) and phospholamban, associated with upregulated Na(+)-Ca(2+) exchanger levels following acute methamphetamine exposure. In addition, methamphetamine promoted overt cardiomyocyte protein damage evaluated by carbonyl formation. Taken together, these results demonstrate direct cardiac depressant effect of methamphetamine in myocardium and isolated cardiomyocytes, possibly associated with protein damage and dampened adrenergic response.

  16. Acute Methamphetamine Exposure Inhibits Cardiac Contractile Function

    PubMed Central

    Turdi, Subat; Schamber, Robbie M.; Roe, Nathan D.; Chew, Herbert G.; Culver, Bruce; Ren, Jun

    2009-01-01

    Methamphetamine, a commonly seen substance of abuse, has been reported to exert detrimental effect on bodily function including the cardiovascular system although its mechanism of action is poorly understood. This study was designed to examine the direct impact of methamphetamine on isolated whole heart and single cardiomyocyte contractile function. Murine hearts and isolated cardiomyocytes from adult FVB mice were exposed to various concentrations of methamphetamine for 30 min prior to the assessment of mechanical function using a Langendroff apparatus and an IonOptix Myocam® system, respectively. Cardiac contractile properties analyzed included maximal velocity of left ventricular pressure development and decline (± dP/dt), peak shortening amplitude (PS), maximal velocity of shortening/relengthening (± dLdt), time-to-PS (TPS), time-to-90% relengthening (TR90), resting and electrically-stimulated increase of intracellular Ca2+ as well as intracellular Ca2+ decay. Our results revealed that acute methamphetamine exposure depressed ± dP/dt, PS and rise of intracellular Ca2+ without affecting ± dLdt, TPS, TR90, resting intracellular Ca2+ and intracellular Ca2+ decay. Furthermore, methamphetamine nullified the adrenergic agonist norepinephrine-elicited positive cardiomyocyte contractile response, including elevated PS, ± dLdt and shortened TR90 without affecting TPS. Western blot analysis showed unchanged expression of sarco(endo)plasmic reticulum Ca2+-ATPase (SERCA2a) and phospholamban, associated with upregulated Na+-Ca2+ exchanger levels following acute methamphetamine exposure. In addition, methamphetamine promoted overt cardiomyocyte protein damage evaluated by carbonyl formation. Taken together, these results demonstrate direct cardiac depressant effect of methamphetamine in myocardium and isolated cardiomyocytes, possibly associated with protein damage and dampened adrenergic response. PMID:19481142

  17. Time course of airway remodelling after an acute chlorine gas exposure in mice

    PubMed Central

    Tuck, Stephanie A; Ramos-Barbón, David; Campbell, Holly; McGovern, Toby; Karmouty-Quintana, Harry; Martin, James G

    2008-01-01

    Accidental chlorine (Cl2) gas inhalation is a common cause of acute airway injury. However, little is known about the kinetics of airway injury and repair after Cl2 exposure. We investigated the time course of airway epithelial damage and repair in mice after a single exposure to a high concentration of Cl2 gas. Mice were exposed to 800 ppm Cl2 gas for 5 minutes and studied from 12 hrs to 10 days post-exposure. The acute injury phase after Cl2 exposure (≤ 24 hrs post-exposure) was characterized by airway epithelial cell apoptosis (increased TUNEL staining) and sloughing, elevated protein in bronchoalveolar lavage fluid, and a modest increase in airway responses to methacholine. The repair phase after Cl2 exposure was characterized by increased airway epithelial cell proliferation, measured by immunoreactive proliferating cell nuclear antigen (PCNA), with maximal proliferation occurring 5 days after Cl2 exposure. At 10 days after Cl2 exposure the airway smooth muscle mass was increased relative to controls, suggestive of airway smooth muscle hyperplasia and there was evidence of airway fibrosis. No increase in goblet cells occurred at any time point. We conclude that a single exposure of mice to Cl2 gas causes acute changes in lung function, including pulmonary responsiveness to methacholine challenge, associated with airway damage, followed by subsequent repair and airway remodelling. PMID:18702818

  18. Acute radiodermatitis from occupational exposure to iridium 192

    SciTech Connect

    Becker, J.; Rosen, T. )

    1989-12-01

    Industrial radiography using the man-made radioisotope iridium 192 is commonplace in the southern states. Despite established procedures and safeguards, accidental exposure may result in typical acute radiodermatitis. We have presented a clinical example of this phenomenon.9 references.

  19. Occupational exposure assessment: Practices in Malaysian nuclear agency

    SciTech Connect

    Sarowi, S. Muhd Ramli, S. A.; Kontol, K. Mohamad; Rahman, N. A. H. Abd.

    2016-01-22

    Malaysian Nuclear Agency (Nuclear Malaysia) is the leading agency in introducing and promoting the application of nuclear science technology in Malaysia. The agency provides major nuclear facilities purposely for research and commercialisation such as reactor, irradiation plants and radioisotope production laboratory. When dealing with ionizing radiation, there is an obligatory requirement to monitor and assess the radiation exposure to the workers. The personal dose of radiation workers were monitored monthly by assessing their Thermoluminescence Dosimeter (TLD) dose reading. This paper will discuss the current practice in managing, assessing, record keeping and reporting of the occupational exposure in Nuclear Malaysia including the Health Physic Group roles and challenges. The statistics on occupational radiation exposure of monitored workers working in different fields in Nuclear Malaysia from 2011 - 2013 will also be presented. The results show that the null hypothesis (H{sub 0}) was accepted which the means of every populations are all equal or not differ significantly. This hypothesis states that the dose exposure received by the radiation workers in Nuclear Malaysia is similar and there were no significant changes from 2011 to 2013. The radiation monitoring programme correlate with the requirement of our national law, the Atomic Energy Licensing Act 1984 (Act 304)

  20. Occupational exposure assessment: Practices in Malaysian nuclear agency

    NASA Astrophysics Data System (ADS)

    Sarowi, S. Muhd; Ramli, S. A.; Kontol, K. Mohamad; Rahman, N. A. H. Abd.

    2016-01-01

    Malaysian Nuclear Agency (Nuclear Malaysia) is the leading agency in introducing and promoting the application of nuclear science technology in Malaysia. The agency provides major nuclear facilities purposely for research and commercialisation such as reactor, irradiation plants and radioisotope production laboratory. When dealing with ionizing radiation, there is an obligatory requirement to monitor and assess the radiation exposure to the workers. The personal dose of radiation workers were monitored monthly by assessing their Thermoluminescence Dosimeter (TLD) dose reading. This paper will discuss the current practice in managing, assessing, record keeping and reporting of the occupational exposure in Nuclear Malaysia including the Health Physic Group roles and challenges. The statistics on occupational radiation exposure of monitored workers working in different fields in Nuclear Malaysia from 2011 - 2013 will also be presented. The results show that the null hypothesis (H₀) was accepted which the means of every populations are all equal or not differ significantly. This hypothesis states that the dose exposure received by the radiation workers in Nuclear Malaysia is similar and there were no significant changes from 2011 to 2013. The radiation monitoring programme correlate with the requirement of our national law, the Atomic Energy Licensing Act 1984 (Act 304).

  1. Occupational exposures and practices in nuclear power plants

    SciTech Connect

    Baum, J.W.

    1989-01-01

    As the first generation of commercial nuclear power comes to a close, it is timely to consider the status of occupational exposure in the power generation industry, that is, the collective occupational radiation doses received by workers in nuclear power plants. The picture is surprising. One might have thought that as newer, larger, and more modern plants came on line, there would be a significant decrease in exposure per unit of electricity generated. There is some indication that this is now happening. One might also have thought that the United States, being a leader in the development of nuclear power, and in the knowledge, experience and technology of nuclear radiation protection, would have the greatest success in controlling exposure. This expectation has not been fulfilled. 32 refs., 4 figs., 5 tabs.

  2. Nuclear medicine in acute and chronic renal failure

    SciTech Connect

    Sherman, R.A.; Byun, K.J.

    1982-07-01

    The diagnostic value of renal scintiscans in patients with acute or chronic renal failure has not been emphasized other than for the estimation of renal size. /sup 131/I OIH, /sup 67/gallium, /sup 99m/TcDTPA, glucoheptonate and DMSA all may be valuable in a variety of specific settings. Acute renal failure due to acute tubular necrosis, hepatorenal syndrome, acute interstitial nephritis, cortical necrosis, renal artery embolism, or acute pyelonephritis may be recognized. Data useful in the diagnosis and management of the patient with obstructive or reflux nephropathy may be obtained. Radionuclide studies in patients with chronic renal failure may help make apparent such causes as renal artery stenosis, chronic pyelonephritis or lymphomatous kidney infiltration. Future correlation of scanning results with renal pathology promises to further expand nuclear medicine's utility in the noninvasive diagnosis of renal disease.

  3. Radiation exposure risks to nuclear well loggers.

    PubMed

    Fujimoto, K; Wilson, J A; Ashmore, J P

    1985-04-01

    This report is based on statistical data from the Canadian National Dose Registry (As82) and information obtained from visits to 1 supplier and 9 oil-well service companies in the Province of Alberta. The companies are representative of most in this industry and provide services at the well head from logging, perforating and fracturing to cementing and tracer work. The information obtained indicates that typical exposures can account for an average dose of 1 to 2 mSv/y. The observations of well-logging procedures revealed a number of potentially hazardous situations which could lead to unnecessary exposure and based upon these, several recommendations are included.

  4. Nuclear imaging in the pediatric acute scrotum

    SciTech Connect

    Valvo, J.R.; Caldamone, A.A.; O'Mara, R.; Rabinowitz, R.

    1982-09-01

    The acute scrotum in the pediatric patient frequently presents a diagnostic dilemma for even the most experienced clinician. In an effort to improve testicular salvage in equivocal cases, immediate surgical intervention has been recommended, despite a large number of unnecessary explorations. Evaluating the sodium pertechnetate /sup 99m/Tc radioisotopic scan in 46 boys, we found this study to be a rapid, reliable, sensitive, and noninvasive test that allows the selection of those patients who require immediate surgical intervention.

  5. Nuclear renal imaging in acute pyelonephritis

    SciTech Connect

    Handmaker, H.

    1982-07-01

    Patients with acute pyelonephritis may present with a spectrum of clinical signs and symptoms. There are few noninvasive diagnostic studies, however, to confirm or exclude this diagnosis. A small number of patients, generally those with severe disease, will demonstrate radiographic changes on excretory urography, but the lack of sensitivity of the IVP in early, acute pyelonephritis is well documented. Several radionuclide techniques have been proposed to assist in the earlier detection of this clinical problem including imaging with Mercury-197 chlormerodrin, Gallium-67 citrate, Technetium-99m glucoheptonate. Technetium-99m DMSA, and, more recently, Indium-111 labeled white blood cells. The success of the renal cortical imaging agents as well as those which localize in infection are described in this report. There appears to be a complimentary role or the cortical imaging agents and the radiopharmaceuticals which localize in bacterial infection. Cortical agents offer the advantage of specific assessment of functioning renal tissue and a convenient, rapid method for following the response to treatment in a noninvasive manner. A pattern is described which may be diagnostic; correlation with Gallium-67 citrate of Indium-111 WBCs may increase the probability of infection as the cause for the cortical abnormality. The measurement of differential renal function using cortical agents provides additional information to assist the clinician in predicting the late effects of infection. Improved sensitivity and specificity, and a reproducible method for following the response to therapy in patients with acute pyelonephritis are the advantages of the techniques described.

  6. Formaldehyde exposure and acute health effects study

    SciTech Connect

    Quackenboss, J.J.; Lebowitz, M.D.; Michaud, J.P.; Bronnimann, D. )

    1989-01-01

    To assess the effects of formaldehyde exposures on health, exposure groups were defined using baseline exposure and health questionnaires. Formaldehyde concentrations were poorly correlated with these exposure classifications, perhaps due to the time delay between classification and monitoring. The 151 households reported here had a mean HCHO concentration of 35 (S.E. 1.5 and median 30) {mu}g/m{sup 3}. Passive samplers prepared in our lab were calibrated in a chamber to derive an estimated sampling rate of 0.311 {mu}g/(mg {center dot} m{sup {minus}3} {center dot} hr). They were also compared to commercially available samplers inside of the homes, with a correlation coefficient of 0.896 and mean difference of 2.6 {mu}g/m{sup 3}. In this report of initial findings from an ongoing study, daily symptoms and peak expiratory flow measurements were compared with an HCHO exposure classification based on the median measured concentrations. None of the symptoms groups were related to HCHO exposure when controlling for age and sex. There was a significant relationship between HCHO exposure and variability in peak expiratory flows that was dependent on age group. It may be especially important to assess the variability in reactive individuals and children to determine the short-term effects of HCHO exposures and possible long-term consequences.

  7. Regulation of adenosine transport by acute and chronic ethanol exposure

    SciTech Connect

    Nagy, L.E.; Casso, D.; Diamond, I.; Gordon, A.S. )

    1989-02-09

    Chronic exposure to ethanol results in a desensitization of adenosine receptor-stimulated cAMP production. Since adenosine is released by cells and is known to desensitize its own as well as other receptors, it may be involved in ethanol-induced desensitization of adenosine receptor function. Therefore, we have examine the acute and chronic effects of ethanol on the transport of adenosine via the nucleoside transport. Acute exposure to ethanol caused an inhibition of adenosine uptake in S49 lymphoma cells. This decrease in uptake resulted in accumulation of extracellular adenosine after ethanol exposure. The effect of ethanol was specific to nucleoside transport. Uptake of uridine, also transported by the nucleoside transporter, was inhibited by ethanol to the same degree as adenosine uptake, while neither isoleucine nor deoxyglucose uptake was altered by ethanol treatment. Inhibition of adenosine uptake by ethanol was non-competitive and dependent on the concentration of ethanol. After chronic exposure to ethanol, cells became tolerant to the acute effects of ethanol. There was no longer an acute inhibition of adenosine uptake, nor was these accumulation of extracellular adenosine. Chronic ethanol exposure also resulted in a decrease in the absolute rate of adenosine uptake. Binding studies using a high affinity lignad for the nucleoside transporter, nitrobenzylthioinosine (NBMPR), indicate that this decreased uptake was due to a decrease in the maximal number of binding sites. These ethanol-induced changes in adenosine transport may be important for the acute and chronic effects of ethanol.

  8. Radiation exposure and lung disease in today's nuclear world.

    PubMed

    Deas, Steven D; Huprikar, Nikhil; Skabelund, Andrew

    2017-03-01

    Ionizing radiation poses important health risks. The per capita annual dose rate has increased in the United States and there is increasing concern for the risks posed by low-dose occupational exposure among workers in nuclear industries and healthcare. Recent nuclear accidents and concern for terrorism have heightened concern for catastrophic, high-dose ionizing radiation exposure. This review will highlight recent research into the risks to lung health posed by ionizing radiation exposure and into potential treatments. Angiotensin-converting enzyme inhibitors and some antioxidants have shown promise as mitigators, to decrease pneumonitis and fibrosis when given after exposure. Studies of survivors of nuclear catastrophes have shown increased risk for lung cancer, especially in nonsmokers. There is evidence for increased lung cancer risk in industrial radiation workers, especially those who process plutonium and may inhale radioactive particles. There does not seem to be an increased risk of lung cancer in healthcare workers who perform fluoroscopic procedures. High-dose ionizing radiation exposure causes pneumonitis and fibrosis, and more research is needed to develop mitigators to improve outcomes in nuclear catastrophes. Long-term, low-dose occupational radiation may increase lung cancer risk. More research to better define this risk could lead to improved safety protocols and screening programs.

  9. Serum metabonomics of acute leukemia using nuclear magnetic resonance spectroscopy

    PubMed Central

    Musharraf, Syed Ghulam; Siddiqui, Amna Jabbar; Shamsi, Tahir; Choudhary, M. Iqbal; Rahman, Atta-ur

    2016-01-01

    Acute leukemia is a critical neoplasm of white blood cells. In order to differentiate between the metabolic alterations associated with two subtypes of acute leukemia, acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML), we investigated the serum of ALL and AML patients and compared with two controls (healthy and aplastic anemia) using 1H NMR (nuclear magnetic resonance) spectroscopy. Thirty-seven putative metabolites were identified using Carr-Purcell-Meiboom-Gill (CPMG) sequence. The use of PLS-DA and OPLS-DA models gave results with 84.38% and 90.63% classification rate, respectively. The metabolites responsible for classification are mainly lipids, lactate and glucose. Compared with controls, ALL and AML patients showed serum metabonomic differences involving aberrant metabolism pathways including glycolysis, TCA cycle, lipoprotein changes, choline and fatty acid metabolisms. PMID:27480133

  10. Acute physiologic effects of secondhand smoke exposure in children.

    PubMed

    Moss, Deborah R; Lucht, Lorrie A; Kip, Kevin E; Reis, Steven E

    2010-07-01

    We investigated the hypothesis that exhaled carbon monoxide (eCO), heart rate (HR), and blood pressure (BP) would increase acutely in exposed but not in unexposed children. In a nonrandomized controlled design, parent-child dyads were assigned to groups based on exposure: child subjects, 7-18 years of age, exposed to smoking daily in the home (exposed) or with no household exposure (unexposed control). HR, BP, and eCO were measured before and after exposure to a parent smoking 1 cigarette (exposed) or a time-lapse equivalent (control). The primary analysis compared mean acute changes in physiological measures following intervention or control procedure. Forty-one dyads were enrolled. At baseline, no differences in child gender, race, ethnicity, HR, BP, lipids, or fasting glucose were noted between exposure groups. Following experimental or control procedures, the median change in eCO was similar between groups (-0.1 ppm exposed vs. 0.0 ppm unexposed, p = .27). Acute hemodynamic changes were also similar between exposed and unexposed children, respectively: (HR change 4.2 vs. 2.6 beats per minute, p = .62; systolic blood pressure change 0.08 vs. 0.41 mm Hg, p = .91; diastolic blood pressure 0.08 vs. 2.27 mm Hg, p = .37). This is the first study to report on acute physiologic changes of secondhand smoke exposure in children in a naturalistic setting. A single acute dose of passive smoke exposure in children did not alter the physiologic variables of HR or BP. Further in-home study using continuous monitoring is needed. Demonstration of acute effects may serve as clinical feedback to motivate parents to quit smoking.

  11. Nuclear medicine in the acute clinical setting: indications, imaging findings, and potential pitfalls.

    PubMed

    Uliel, Livnat; Mellnick, Vincent M; Menias, Christine O; Holz, Andrew L; McConathy, Jonathan

    2013-01-01

    Nuclear medicine imaging provides valuable functional information that complements information obtained with anatomic imaging techniques in the evaluation of patients with specific acute clinical manifestations. Nuclear medicine studies are most often used in conjunction with other imaging modalities and as a problem-solving tool. Under certain circumstances a nuclear medicine study may be indicated as the first-line imaging modality, as in the case of renal scintigraphy for transplant dysfunction in the early postoperative period. Nuclear imaging may be preferred when a conventional first-line study is contraindicated or when it is important to minimize radiation exposure. The portability of nuclear imaging offers particular advantages for the evaluation of critically ill patients whose clinical condition is unstable and who cannot be safely transported out of the intensive care unit. The ability to visualize physiologic and pathophysiologic processes over relatively long time periods without adding to the patient's radiation exposure contributes to the high diagnostic sensitivity of several types of nuclear medicine studies. Viewing the acquired images in the cine mode adds to the value of these studies for diagnosing and characterizing dynamic abnormalities such as intermittent internal bleeding and bile or urine leakage. In this pictorial review, the spectrum of nuclear medicine studies commonly performed in the acute care setting is reviewed according to body systems and organs, with detailed descriptions of the indications, technical considerations, findings, and potential pitfalls of each type of study. Supplemental material available at http://radiographics.rsna.org/lookup/suppl/doi:10.1148/rg.332125098/-/DC1.

  12. Fabrication of high exposure nuclear fuel pellets

    DOEpatents

    Frederickson, James R.

    1987-01-01

    A method is disclosed for making a fuel pellet for a nuclear reactor. A mixture is prepared of PuO.sub.2 and UO.sub.2 powders, where the mixture contains at least about 30% PuO.sub.2, and where at least about 12% of the Pu is the Pu.sup.240 isotope. To this mixture is added about 0.3 to about 5% of a binder having a melting point of at least about 250.degree. F. The mixture is pressed to form a slug and the slug is granulated. Up to about 4.7% of a lubricant having a melting point of at least about 330.degree. F. is added to the granulated slug. Both the binder and the lubricant are selected from a group consisting of polyvinyl carboxylate, polyvinyl alcohol, naturally occurring high molecular weight cellulosic polymers, chemically modified high molecular weight cellulosic polymers, and mixtures thereof. The mixture is pressed to form a pellet and the pellet is sintered.

  13. Pulmonary Inflammatory Responses to Acute Meteorite Dust Exposures - to Acute Meteorite Dust Exposures - Exploration

    NASA Technical Reports Server (NTRS)

    Harrington, A. D.; McCubbin, F. M.; Kaur, J.; Smirnov, A.; Galdanes, K.; Schoonen, M. A. A.; Chen, L. C.; Tsirka, S. E.; Gordon, T.

    2017-01-01

    New initiatives to begin lunar and martian colonization within the next few decades are illustrative of the resurgence of interest in space travel. One of NASA's major concerns with extended human space exploration is the inadvertent and repeated exposure to unknown dust. This highly interdisciplinary study evaluates both the geochemical reactivity (e.g. iron solubility and acellular reactive oxygen species (ROS) generation) and the relative toxicity (e.g. in vitro and in vivo pulmonary inflammation) of six meteorite samples representing either basalt or regolith breccia on the surface of the Moon, Mars, and Asteroid 4Vesta. Terrestrial mid-ocean ridge basalt (MORB) is also used for comparison. The MORB demonstrated higher geochemical reactivity than most of the meteorite samples but caused the lowest acute pulmonary inflammation (API). Notably, the two martian meteorites generated some of the highest API but only the basaltic sample is significantly reactive geochemically. Furthermore, while there is a correlation between a meteorite's soluble iron content and its ability to generate acellular ROS, there is no direct correlation between a particle's ability to generate ROS acellularly and its ability to generate API. However, assorted in vivo API markers did demonstrate strong positive correlations with increasing bulk Fenton metal content. In summary, this comprehensive dataset allows for not only the toxicological evaluation of astromaterials but also clarifies important correlations between geochemistry and health.

  14. Nuclear receptors in acute and chronic cholestasis.

    PubMed

    Gonzalez-Sanchez, Ester; Firrincieli, Delphine; Housset, Chantal; Chignard, Nicolas

    2015-01-01

    Nuclear receptors (NRs) form a family of 48 members. NRs control hepatic processes such as bile acid homeostasis, lipid metabolism and mechanisms involved in fibrosis and inflammation. Due to their central role in the regulation of hepatoprotective mechanisms, NRs are promising therapeutic targets in cholestatic disorders. NRs can be classified into five different physiological clusters. NRs from the 'bile acids and xenobiotic metabolism' and from the 'lipid metabolism and energy homeostasis' clusters are strongly expressed in the liver. Furthermore, NRs from these clusters, such as farnesoid X receptor α (FXRα), pregnane X receptor (PXR) and peroxisome proliferator-activated receptors (PPARs), have been associated with the pathogenesis and the progression of cholestasis. The latter observation is also true for vitamin D receptor (VDR), which is barely detectable in the whole liver, but has been linked to cholestatic diseases. Involvement of VDR in cholestasis is ascribed to a strong expression in nonparenchymal liver cells, such as biliary epithelial cells, Kupffer cells and hepatic stellate cells. Likewise, NRs from other physiological clusters with low hepatic expression, such as estrogen receptor α (ERα) or reverse-Erb α/β (REV-ERB α/β), may also control pathophysiological processes in cholestasis. In this review, we will describe the impact of individual NRs on cholestasis. We will then discuss the potential role of these transcription factors as therapeutic targets. 2015 S. Karger AG, Basel.

  15. 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.

  16. Lung function after acute chlorine exposure

    SciTech Connect

    Jones, R.N.; Hughes, J.M.; Glindmeyer, H.; Weill, H.

    1986-12-01

    Chlorine gas, spreading from a train derailment, caused the deaths of 8 persons and the hospitalization of 23 with sublethal respiratory injuries. Twenty-five others had at least one sign of lower respiratory abnormality but were not hospitalized. One hundred thirteen who were examined for gas effects in the forty-eight hours after exposure, including 20 of 23 of those hospitalized and 21 of 25 of those not hospitalized but with respiratory abnormality, participated in follow-up studies. Probability of admission to hospital was related to distance from the spill, but by 3 wk after exposure there was no detectable difference in lung function relating to distance or apparent severity of injury. In 60 adults tested multiple times over the following 6 yr, longitudinal change in lung function showed expected differences related to smoking but none related to distance or severity of injury. The average annual change in FEV was -34 ml/yr in current smokers and -18 ml/yr in ex and never-smokers. The lack of a discernible chlorine effect in this cohort accords with the findings in most previous studies. Without pre-exposure measurements, a single, lasting reduction in lung function cannot be excluded, but there is no evidence for a persisting abnormal rate of decline.

  17. Advanced medical countermeasures for radiological accidents and nuclear disasters: prevention, prophylaxis, treatment and pre- and post-exposure management.

    NASA Astrophysics Data System (ADS)

    Popov, Dmitri; Maliev, Slava; Jones, Jeffrey

    Countermeasures against nuclear terrorism to prevent or limit the number of irradiated human population or radiation intoxications include early identification of the nuclear terrorism event and all persons which exposed by radiation, decontamination program and procedures, radiation control, and medical countermeasures which include medical diagnosis,differential diagnosis of Acute Radiation Syndromes by Immune Enzyme Assay , pre-exposure vaccination with Human Antiradiation Vaccine, post-exposure specific treatment - de-intoxication with Radiation Antidote IgG (blocking Antiradiation Antibodies). Our Advanced Medical Technology elaborated as a part of effective countermeasure include Plan of Action.Countermeasures against nuclear terrorism to prevent or limit the number of high level of lethality and severe forms of radiation illness or intoxications include A.early identification of the nuclear terrorism event and persons exposed,b. appropriate decontamination, c. radiation control, and d.medical countermeasures and medical management of ARS. Medical countermeasures, which include medical interventions such as active immuneprophylaxis with Human Antiradiation Vaccine , passive immune-prophylaxis with Antiradiation Antitoxins immune-globulins IgG , and chemoprophylaxis - post-exposure antioxidants prophylaxis and antibioticprophylaxis. Medical countermeasures with Antiradiation Vaccine should be initiated before an exposure (if individuals are identified as being at high risk for exposure)but after a confirmed exposure event Antiradiation Vaccine not effective and Antiradiation Antidot IgG must be applyed for treatment of Acute Radiation Syndromes.

  18. Development of acute exposure guideline levels for airborne exposures to hazardous substances.

    PubMed

    Krewski, Daniel; Bakshi, Kulbir; Garrett, Roger; Falke, Ernest; Rusch, George; Gaylor, David

    2004-04-01

    Hazardous substances can be released into the atmosphere due to industrial and transportation accidents, fires, tornadoes, earthquakes, and terrorists, thereby exposing workers and the nearby public to potential adverse health effects. Various enforceable guidelines have been set by regulatory agencies for worker and ambient air quality. However, these exposure levels generally are not applicable to rare lifetime acute exposures, which possibly could occur at high concentrations. Acute exposure guideline levels (AEGLs) provide estimates of concentrations for airborne exposures for an array of short durations that possibly could cause mild (AEGL-1), severe, irreversible, potentially disabling adverse health effects (AEGL-2), or life threatening effects (AEGL-3). These levels can be useful for emergency responders and planners in reducing or eliminating potential risks to the public. Procedures and methodologies for deriving AEGLs are reviewed in this paper that have been developed in the United States, with direct input from international representatives of OECD member-countries, by the National Advisory Committee for Acute Exposure Guidelines for Hazardous Substances and reviewed by the National Research Council. Techniques are discussed for the extrapolation of effects across different exposure durations. AEGLs provide a viable approach for assisting in the prevention, planning, and response to acute airborne exposures to toxic agents.

  19. Biomarkers of Acute Respiratory Allergen Exposure: Screening For Sensitization Potential

    EPA Science Inventory

    Rationale: An in vitro assay to identify respiratory sensitizers will provide a rapid screen and reduce animal use. The study goal was to identify biomarkers that differentiate allergen versus non-allergen responses following an acute exposure. Methods: Female BALB/c mice rec...

  20. Biomarkers of Acute Respiratory Allergen Exposure: Screening For Sensitization Potential

    EPA Science Inventory

    Rationale: An in vitro assay to identify respiratory sensitizers will provide a rapid screen and reduce animal use. The study goal was to identify biomarkers that differentiate allergen versus non-allergen responses following an acute exposure. Methods: Female BALB/c mice rec...

  1. EFFECTS OF ACUTE PYRETHROID EXPOSURE ON THERMOREGULATION IN RATS.

    EPA Science Inventory

    Pyrethroid insecticides produce acute neurotoxicity in mammals. According to the FQPA mandate, the USEPA is required to consider the risk of cumulative toxicity posed to humans through exposure to pyrethroid mixtures. Thermoregulatory response (TR) is being used to determine if t...

  2. Health Impacts from Acute Radiation Exposure

    SciTech Connect

    Strom, Daniel J.

    2003-09-30

    Absorbed doses above1-2 Gy (100-200 rads) received over a period of a day or less lead to one or another of the acute radiation syndromes. These are the hematopoietic syndrome, the gastrointestinal (GI) syndrome, the cerebrovascular (CV) syndrome, the pulmonary syndrome, or the cutaneous syndrome. The dose that will kill about 50% of the exposed people within 60 days with minimal medical care, LD50-60, is around 4.5 Gy (450 rads) of low-LET radiation measured free in air. The GI syndrome may not be fatal with supportive medical care and growth factors below about 10 Gy (1000 rads), but above this is likely to be fatal. Pulmonary and cutaneous syndromes may or may not be fatal, depending on many factors. The CV syndrome is invariably fatal. Lower acute doses, or protracted doses delivered over days or weeks, may lead to many other health outcomes than death. These include loss of pregnancy, cataract, impaired fertility or temporary or permanent sterility, hair loss, skin ulceration, local tissue necrosis, developmental abnormalities including mental and growth retardation in persons irradiated as children or fetuses, radiation dermatitis, and other symptoms listed in Table 2 on page 12. Children of parents irradiated prior to conception may experience heritable ill-health, that is, genetic changes from their parents. These effects are less strongly expressed than previously thought. Populations irradiated to high doses at high dose rates have increased risk of cancer incidence and mortality, taken as about 10-20% incidence and perhaps 5-10% mortality per sievert of effective dose of any radiation or per gray of whole-body absorbed dose low-LET radiation. Cancer risks for non-uniform irradiation will be less.

  3. Acute exposure to environmental tobacco smoke and heart rate variability.

    PubMed Central

    Pope, C A; Eatough, D J; Gold, D R; Pang, Y; Nielsen, K R; Nath, P; Verrier, R L; Kanner, R E

    2001-01-01

    Environmental tobacco smoke (ETS) has been associated with cardiovascular mortality. Pathophysiologic pathways leading from ETS exposure to cardiopulmonary disease are still being explored. Reduced cardiac autonomic function, as measured by heart rate variability (HRV), has been associated with cardiac vulnerability and may represent an important pathophysiologic mechanism linking ETS and risk of cardiac mortality. In this study we evaluated acute ETS exposure in a commercial airport with changes in HRV in 16 adult nonsmokers. We conducted ambulatory electrocardiographic (ECG) monitoring for 8-hr periods while participants alternated 2 hr in nonsmoking and smoking areas. Nicotine and respirable suspended particle concentrations and participants' blood oxygen saturation were also monitored. We calculated time and frequency domain measures of HRV for periods in and out of the smoking area, and we evaluated associations with ETS using comparative statistics and regression modeling. ETS exposure was negatively associated with all measures of HRV. During exposure periods, we observed an average decrement of approximately 12% in the standard deviation of all normal-to-normal heart beat intervals (an estimate of overall HRV). ETS exposures were not associated with mean heart rate or blood oxygen saturation. Altered cardiac autonomic function, assessed by decrements in HRV, is associated with acute exposure to ETS and may be part of the pathophysiologic mechanisms linking ETS exposure and increased cardiac vulnerability. PMID:11485870

  4. Acute inhalation exposure of azodicarbonamide in the guinea pig.

    PubMed

    Shopp, G M; Cheng, Y S; Gillett, N A; Bechtold, W E; Medinsky, M A; Hobbs, C H; Birnbaum, L S; Mauderly, J L

    1987-02-01

    Humans have been exposed to azodicarbonamide (ADA) by inhalation where bulk quantities of ADA are handled in the workplace. Responses of some workers have led to concern for the potential irritant and sensitizing properties of inhaled ADA. This study examined the effects of inhaling ADA on lung structure and function of guinea pigs during and after an acute exposure. Groups of 20 guinea pigs were exposed to each of 3 concentrations of ADA (19, 58, and 97 mg/m3), plus air as a control, for 1 hr. Pulmonary function was measured before exposure (baseline), during exposure, immediately after exposure and 24 hr after exposure. Dynamic compliance (Cdyn), total pulmonary resistance (RL), tidal volume (VT), respiratory frequency and minute volume were measured. In addition, gross necropsies and histological examinations of respiratory tract tissues were done either immediately following the exposure or 24 hr after exposure. There were no effects of ADA exposure on gross necropsy, histology, Cdyn, or RL. Some significant, concentration-related decreases in VT, respiratory frequency and minute volume were seen. The magnitudes of these changes were small: the largest change was seen in minute volume, amounting to a 24% decrease in the high concentration group. Inhalation exposure of guinea pigs to ADA at concentrations of up to 97 mg/m3 resulted in minor changes in pulmonary function without any changes in lung histology.

  5. Gastric acid response to acute exposure to hypergravity

    PubMed Central

    Yoon, Gun; Kim, Hyun-Soo

    2017-01-01

    The influence of environmental stressors on the pathogenesis of gastrointestinal disease has received increased awareness. Stress affects different physiological functions of the gastrointestinal tract, including gastric acid secretion and mucosal blood flow. Repeated exposures of rapid-onset, highly-sustained hypergravity cause severe physical stress in the pilot. Although the effects of exposure to hypergravity on cardiovascular and cerebral functions have been the subjects of numerous studies, crucial information regarding pathophysiological changes in the gastrointestinal tract following hypergravity exposure is lacking. In this study, we investigated the effects of acute exposure to hypergravity on gastric secretory activity and gastrin release. Male Sprague-Dawley rats were exposed to +10Gz three times for 3 min. Gastric juice and blood were collected. The volume and total acidity of gastric juice, and the plasma gastrin level was measured. Acute exposure to +10Gz significantly decreased the gastric juice parameters. The gastric juice volume and total acidity of hypergravity-exposed rats were 3.54 ± 0.32 mL/100 g and 84.90 ± 5.17 mEq/L, respectively, which were significantly lower than those of the nonexposed rats (4.62 ± 0.39 mL/100 g and 97.37 ± 5.42 mEq/L; P < 0.001 and P < 0.001, respectively). In contrast, plasma gastrin level was not significantly altered following hypergravity exposure. We demonstrated that acute exposure to hypergravity led to a significant decrease in the gastric juice volume and acidity but did not alter the plasma gastrin level. PMID:27992379

  6. Role of American Nuclear Insurers in reducing occupational radiation exposure

    SciTech Connect

    Forbes, J.L.

    1980-01-01

    Since 1957 the nuclear insurance pools have provided liability and property insurance for the nation's nuclear power generating stations as mandated by the Price-Anderson Act. Although the insurance was originally structured to give financial protection to the insured in the event of a major accident, the potential for third-party claims arising from routine occupational exposure is becoming a more realistic pathway for a loss to the pools. In order to give maximum protection to the pools' assets, the Liability Engineering Department of American Nuclear Insurers (ANI) performs periodic inspections of the power plants. By concentrating on programs and management areas, ANI inspections complement regulatory inspections so that all major areas of common interest are reviewed. This paper presents the nature, results, and findings of those periodic inspections particularly in the general area of plant radiation protection.

  7. Long Duration Hot Hydrogen Exposure of Nuclear Thermal Rocket Materials

    NASA Technical Reports Server (NTRS)

    Litchford, Ron J.; Foote, John P.; Hickman, Robert; Dobson, Chris; Clifton, Scooter

    2007-01-01

    An arc-heater driven hyper-thermal convective environments simulator was recently developed and commissioned for long duration hot hydrogen exposure of nuclear thermal rocket materials. This newly established non-nuclear testing capability uses a high-power, multi-gas, wall-stabilized constricted arc-heater to .produce high-temperature pressurized hydrogen flows representative of nuclear reactor core environments, excepting radiation effects, and is intended to serve as a low cost test facility for the purpose of investigating and characterizing candidate fuel/structural materials and improving associated processing/fabrication techniques. Design and engineering development efforts are fully summarized, and facility operating characteristics are reported as determined from a series of baseline performance mapping runs and long duration capability demonstration tests.

  8. 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.

  9. Nuclear-weapon-effect research at PSR (Pacific-Sierra Research Corporation) - 1983. Volume 10. Symptomatology of acute radiation effects in humans after exposure to doses of 75 to 4500 rads (cGy) free-in-air. Final technical report, 27 October 1982-30 November 1983

    SciTech Connect

    Baum, S.J.; Young, R.W.; Anno, G.H.; Withers, H.R.

    1984-08-31

    This report distills from available data descriptions of typical human symptoms in reaction to prompt ionizing radiation in the dose range 75 to 4500 rads (cGy) free-in-air. The descriptions correlate symptoms with dose and time over the acute post-exposure period of six weeks. Their purpose is to provide an empirical base for estimating combat troop performance after a nuclear weapon attack. The dose range of interest is subdivided into eight subranges associated with important pathophysiological events. For each subrange, the signs and symptoms manifested by an exposed population are estimated--symptom onset, severity, duration, and incidence. The early or prodromal phase of radiation sickness begins about 2 to 4 hrs after doses of 300 to 530 rads (cGy). Onset time diminishes with dose, occurring within minutes of exposure to 4500 rads (cGy). Characteristic prodromal symptoms are nausea, vomiting, anorexia, and diarrhea. The prodromal phase lasts from several days to a matter of hours, depending on dose. Symptoms of the hemopoietic syndrome are bleeding, fever, infection, and ulceration. Symptoms of the gastrointestinal syndrome are fluid loss, electrolyte imbalance, severe diarrhea, and septicemia.

  10. Management of acute traumatic stress in nuclear and radiological emergencies.

    PubMed

    Vazquez, Marina; Jordan, Osvaldo; Kuper, Enrique; Hernandez, Daniel; Galmarini, Martin; Ferraro, Augusto

    2010-06-01

    In order to effectively respond to and minimize the psychological impact following disasters, such as radio-nuclear ones, it is essential to understand the mechanisms involved in such conditions and how to prevent and treat the psychological impacts, including those related to acute traumatic stress and its consequences across life span. Radio-nuclear emergencies may cause psychological traumatic stress, with its potentially significant consequences in mental health, with both short and long-term effects, which extend beyond the individuals directly affected. Ionizing radiation cannot be perceived by human senses and most people are unaware of the magnitude of its effects, which could result in feelings of helplessness and vulnerability. Those situations with a high degree of uncertainty, regarding potential future health effects, are more psychologically traumatic than others. The present century has witnessed a steady increase in the number of publications concerning the mental health impact of traumatic events, showing the need of increasing the study of traumatic stress and its impact on mental health. A prompt, planned and effective response to manage disaster-induced acute traumatic stress may prevent the evolutionary reactions of traumatic stress into disorders or even chronic stress diseases that can appear after a nuclear or radiological emergency.

  11. Evaluation of exposure limits to toxic gases for nuclear reactor control room operators

    SciTech Connect

    Mahlum, D.D.; Sasser, L.B. )

    1991-07-01

    We have evaluated ammonia, chlorine, Halon (actually a generic name for several halogenated hydro-carbons), and sulfur dioxide for their possible effects during an acute two-minute exposure in order to derive recommendations for maximum exposure levels. To perform this evaluation, we conducted a search to find the most pertinent literature regarding toxicity in humans and in experimental animals. Much of the literature is at least a decade old, not an unexpected finding since acute exposures are less often performed now than they were a few years ago. In most cases, the studies did not specifically examine the effects of two-minute exposures; thus, extrapolations had to be made from studies of longer-exposure periods. Whenever possible, we gave the greatest weight to human data, with experimental animal data serving to strengthen the conclusion arrived at from consideration of the human data. Although certain individuals show hypersensitivity to materials like sulfur dioxide, we have not attempted to factor this information into the recommendations. After our evaluation of the data in the literature, we held a small workshop. Major participants in this workshop were three consultants, all of whom were Diplomates of the American Board of Toxicology, and staff from the Nuclear Regulatory Commission. Our preliminary recommendations for two-minute exposure limits and the rationale for them were discussed and consensus reached on final recommendations. These recommendations are: (1) ammonia-300 to 400-ppm; (2) chlorine-30 ppm; (3) Halon 1301-5%; Halon 1211-2%; and (4) sulfur dioxide-100 ppm. Control room operators should be able to tolerate two-minute exposures to these levels, don fresh-air masks, and continue to operate the reactor if the toxic material is eliminated, or safely shut down the reactor if the toxic gas remains. 96 refs., 9 tabs.

  12. Medical mitigation strategies for acute radiation exposure during spaceflight.

    PubMed

    Epelman, Slava; Hamilton, Douglas R

    2006-02-01

    The United States Government has recently refocused their space program on manned missions to the Moon by 2018 and later to Mars. While there are many potential risks associated with exploration-class missions, one of the most serious and unpredictable is the effect of acute space radiation exposure, and the space program must make every reasonable effort to mitigate this risk. The two cosmic sources of radiation that could impact a mission outside the Earth's magnetic field are solar particle events (SPE) and galactic cosmic radiation (GCR). Either can cause acute and chronic medical illness. Numerous researchers are currently examining the ability of GCR exposure to induce the development of genetic changes that lead to malignancies and other delayed effects. However, relatively little has been published on the medical management of an acute SPE event and the potential impact on the mission and crew. This review paper will provide the readers with medical management options for an acute radiation event based on recommendations from the Department of Homeland Security (DHS), Centers for Disease Control (CDC), and evidence-based critical analysis of the scientific literature. It is the goal of this paper to stimulate debate regarding the definition of safety parameters for exploration-class missions to determine the level of medical care necessary to provide for the crew that will undertake such missions.

  13. Sensory and Cognitive Effects of Acute Exposure to Hydrogen Sulfide

    PubMed Central

    Fiedler, Nancy; Kipen, Howard; Ohman-Strickland, Pamela; Zhang, Junfeng; Weisel, Clifford; Laumbach, Robert; Kelly-McNeil, Kathie; Olejeme, Kelechi; Lioy, Paul

    2008-01-01

    Background Some epidemiologic studies have reported compromised cognitive and sensory performance among individuals exposed to low concentrations of hydrogen sulfide (H2S). Objectives We hypothesized a dose–response increase in symptom severity and reduction in sensory and cognitive performance in response to controlled H2S exposures. Methods In separate exposure sessions administered in random order over three consecutive weeks, 74 healthy subjects [35 females, 39 males; mean age (± SD) = 24.7 ± 4.2; mean years of education = 16.5 ± 2.4], were exposed to 0.05, 0.5, and 5 ppm H2S. During each exposure session, subjects completed ratings and tests before H2S exposure (baseline) and during the final hour of the 2-hr exposure period. Results Dose–response reduction in air quality and increases in ratings of odor intensity, irritation, and unpleasantness were observed. Total symptom severity was not significantly elevated across any exposure condition, but anxiety symptoms were significantly greater in the 5-ppm than in the 0.05-ppm condition. No dose–response effect was observed for sensory or cognitive measures. Verbal learning was compromised during each exposure condition. Conclusions Although some symptoms increased with exposure, the magnitude of these changes was relatively minor. Increased anxiety was significantly related to ratings of irritation due to odor. Whether the effect on verbal learning represents a threshold effect of H2S or an effect due to fatigue across exposure requires further investigation. These acute effects in a healthy sample cannot be directly generalized to communities where individuals have other health conditions and concomitant exposures. PMID:18197303

  14. Chronic nicotine exposure exacerbates acute renal ischemic injury

    PubMed Central

    Grifoni, Samira; Clark, Jeb S.; Csongradi, Eva; Maric, Christine; Juncos, Luis A.

    2011-01-01

    Recent epidemiological reports showed that smoking has a negative impact on renal function and elevates the renal risk not only in the renal patient but perhaps also in the healthy population. Studies suggested that nicotine, a major tobacco alkaloid, links smoking to renal dysfunction. While several studies showed that smoking/chronic nicotine exposure exacerbates the progression of chronic renal diseases, its impact on acute kidney injury is virtually unknown. Here, we studied the effects of chronic nicotine exposure on acute renal ischemic injury. We found that chronic nicotine exposure increased the extent of renal injury induced by warm ischemia-reperfusion as evidenced by morphological changes, increase in plasma creatinine level, and kidney injury molecule-1 expression. We also found that chronic nicotine exposure elevated markers of oxidative stress such as nitrotyrosine as well as malondialdehyde. Interestingly, chronic nicotine exposure alone increased oxidative stress and injury in the kidney without morphological alterations. Chronic nicotine treatment not only increased reactive oxygen species (ROS) production and injury but also exacerbated oxidative stress-induced ROS generation through NADPH oxidase and mitochondria in cultured renal proximal tubule cells. The resultant oxidative stress provoked injury through JNK-mediated activation of the activator protein (AP)-1 transcription factor in vitro. This mechanism might exist in vivo as phosphorylation of JNK and its downstream target c-jun, a component of the AP-1 transcription factor, is elevated in the ischemic kidneys exposed to chronic nicotine. Our results imply that smoking may sensitize the kidney to ischemic insults and perhaps facilitates progression of acute kidney injury to chronic kidney injury. PMID:21511693

  15. Chronic nicotine exposure exacerbates acute renal ischemic injury.

    PubMed

    Arany, Istvan; Grifoni, Samira; Clark, Jeb S; Csongradi, Eva; Maric, Christine; Juncos, Luis A

    2011-07-01

    Recent epidemiological reports showed that smoking has a negative impact on renal function and elevates the renal risk not only in the renal patient but perhaps also in the healthy population. Studies suggested that nicotine, a major tobacco alkaloid, links smoking to renal dysfunction. While several studies showed that smoking/chronic nicotine exposure exacerbates the progression of chronic renal diseases, its impact on acute kidney injury is virtually unknown. Here, we studied the effects of chronic nicotine exposure on acute renal ischemic injury. We found that chronic nicotine exposure increased the extent of renal injury induced by warm ischemia-reperfusion as evidenced by morphological changes, increase in plasma creatinine level, and kidney injury molecule-1 expression. We also found that chronic nicotine exposure elevated markers of oxidative stress such as nitrotyrosine as well as malondialdehyde. Interestingly, chronic nicotine exposure alone increased oxidative stress and injury in the kidney without morphological alterations. Chronic nicotine treatment not only increased reactive oxygen species (ROS) production and injury but also exacerbated oxidative stress-induced ROS generation through NADPH oxidase and mitochondria in cultured renal proximal tubule cells. The resultant oxidative stress provoked injury through JNK-mediated activation of the activator protein (AP)-1 transcription factor in vitro. This mechanism might exist in vivo as phosphorylation of JNK and its downstream target c-jun, a component of the AP-1 transcription factor, is elevated in the ischemic kidneys exposed to chronic nicotine. Our results imply that smoking may sensitize the kidney to ischemic insults and perhaps facilitates progression of acute kidney injury to chronic kidney injury.

  16. Reduction of radiation exposure in Japanese BWR Nuclear Power Plants

    SciTech Connect

    Morikawa, Yoshitake

    1995-03-01

    The reduction of occupational exposure to radiation during the annual inspection and maintenance outages of Japanese boiling water reactors (BWR) is one of the most important objectives for stable and reliable operation. It was shown that this radiation exposure is caused by radionuclides, such as Co-60, Co-58 and Mn-54 which are produced from the metal elements Co, Ni, and Fe present in the corrosion products of structural materials that had been irradiated by neutrons. Therefore, to reduce radiation sources and exposures in Japanese BWRs, attempts have been reinforced to remove corrosion products and activated corrosion products from the primary coolant system. This paper describes the progress of the application of these measures to Japanese BWRs. Most Japanese BWR-4 and BWR-5 type nuclear power plants started their commercial operations during the 1970s. With the elapse of time during operations, a problem came to the forefront, namely that occupational radiation exposure during plant outages gradually increased, which obstructed the smooth running of inspections and maintenance work. To overcome this problem, extensive studies to derive effective countermeasures for radiation exposure reduction were undertaken, based on the evaluation of the plants operation data.

  17. [Occupational radiation exposures during maintenance activities at nuclear power plants].

    PubMed

    Imahori, A

    1987-11-01

    Occupational exposures at nuclear power plants occur mostly during maintenance activities rather than during routine reactor operation. In this paper, statistical summaries of occupational exposures during routine maintenance activities for the years 1982-84 at nuclear power plants in Japan are presented, including comparison of the exposure levels by reactor type and by plant age. Average annual collective doses per reactor for BWRs and PWRs are 7.30 man-Sv and 2.84 man-Sv, respectively, and 78% and 89% of annual doses are incurred during maintenance activities. Average annual outage days of BWRs and PWRs for routine maintenance are 102 d and 97 d. Annual collective doses per reactor, most of which occur during maintenance activities, usually increase with plant age. Higher collective doses are observed for routine maintenance performed on older reactors as compared to newer reactors, especially in BWRs. Collective doses accrued during respective routine maintenance activities have a significant correlation with duration of maintenance and number of workers involved in maintenance.

  18. Acute effects of cigarette smoke exposure on experimental skin flaps

    SciTech Connect

    Nolan, J.; Jenkins, R.A.; Kurihara, K.; Schultz, R.C.

    1985-04-01

    Random vascular patterned caudally based McFarlane-type skin flaps were elevated in groups of Fischer 344 rats. Groups of rats were then acutely exposed on an intermittent basis to smoke generated from well-characterized research filter cigarettes. Previously developed smoke inhalation exposure protocols were employed using a Maddox-ORNL inhalation exposure system. Rats that continued smoke exposure following surgery showed a significantly greater mean percent area of flap necrosis compared with sham-exposed groups or control groups not exposed. The possible pathogenesis of this observation as well as considerations and correlations with chronic human smokers are discussed. Increased risks of flap necrosis by smoking in the perioperative period are suggested by this study.

  19. Does acute exposure to mobile phones affect human attention?

    PubMed

    Russo, Riccardo; Fox, Elaine; Cinel, Caterina; Boldini, Angela; Defeyter, Margaret A; Mirshekar-Syahkal, Dariush; Mehta, Amit

    2006-04-01

    Recent studies have indicated that acute exposure to low level radiofrequency (RF) electromagnetic fields generated by mobile phones affects human cognition. However, the relatively small samples used, in addition to methodological problems, make the outcomes of these studies difficult to interpret. In our study we tested a large sample of volunteers (168) using a series of cognitive tasks apparently sensitive to RF exposure (a simple reaction task, a vigilance task, and a subtraction task). Participants performed those tasks twice, in two different sessions. In one session they were exposed to RFs, with half of subjects exposed to GSM signals and the other half exposed to CW signals, while in the other session they were exposed to sham signals. No significant effects of RF exposure on performance for either GSM or CW were found, independent of whether the phone was positioned on the left or on the right side. (c) 2005 Wiley-Liss, Inc.

  20. Acute versus repeated chocolate exposure: effects on intake and cravings in restrained and unrestrained eaters.

    PubMed

    Coelho, Jennifer S; Nederkoorn, Chantal; Jansen, Anita

    2014-04-01

    The cue-reactivity model, which is based on conditioning processes, posits that repeated food exposure (in the absence of consumption) should decrease cue reactivity. To examine whether repeated chocolate exposure attenuates cravings and intake, relative to those exposed to an acute cue, a 2 (repeated vs acute cue) × 2 (restrained vs unrestrained eaters) design was employed. Fifty female participants were recruited. Repeated exposure reduced cravings in unrestrained eaters (relative to acute exposure), but increased cravings in restrained eaters. An interaction between restraint and exposure emerged on intake, such that restrained eaters ate less after acute exposure than did unrestrained eaters.

  1. Prolonged prenatal psychotropic medication exposure alters neonatal acute pain response.

    PubMed

    Oberlander, Tim F; Eckstein Grunau, Ruth; Fitzgerald, Colleen; Ellwood, Ann-Louise; Misri, Shaila; Rurak, Dan; Riggs, Kenneth Wayne

    2002-04-01

    Selective serotonin reuptake inhibitors (SSRIs) and benzodiazepines are frequently used to treat maternal depression during pregnancy, however the effect of increased serotonin (5HT) and gamma-amino-butyric acid (GABA) agonists in the fetal human brain remains unknown. 5HT and GABA are active during fetal neurologic growth and play early roles in pain modulation, therefore, if prolonged prenatal exposure alters neurodevelopment this may become evident in altered neonatal pain responses. To examine biologic and behavioral effects of prenatal exposure, neonatal responses to acute pain (phenylketonuria heel lance) in infants with prolonged prenatal exposure were examined. Facial action (Neonatal Facial Coding System) and cardiac autonomic reactivity derived from the relationship between respiratory activity and short term variations of heart rate (HRV) were compared between 22 infants with SSRI exposure (SE) [fluoxetine (n = 7), paroxetine (n = 11), sertraline (n = 4)]; 16 infants exposed to SSRIs and clonazepam (SE+) [paroxetine (n = 14), fluoxetine (n = 2)]; and 23 nonexposed infants during baseline, lance, and recovery periods of a heel lance. Length of maternal SSRI use did not vary significantly between exposure groups-[mean (range)] SE:SE+ 183 (31-281):141 (54-282) d (p > 0.05). Infants exposed to SE and SE+ displayed significantly less facial activity to heel lance than control infants. Mean HR increased with lance, but was significantly lower in SE infants during recovery. Using measures of HRV and the transfer relationship between heart rate and respiration, SSRI infants had a greater return of parasympathetic cardiac modulation in the recovery period, whereas a sustained sympathetic response continued in the control group. Prolonged prenatal SSRI exposure appears to be associated with reduced behavioral pain responses and increased parasympathetic cardiac modulation in recovery following an acute neonatal noxious event. Possible 5HT-mediated pain inhibition

  2. Acute and chronic effects of erythromycin exposure on oxidative stress and genotoxicity parameters of Oncorhynchus mykiss.

    PubMed

    Rodrigues, S; Antunes, S C; Correia, A T; Nunes, B

    2016-03-01

    Erythromycin (ERY) is a macrolide antibiotic used in human and veterinary medicine, and has been detected in various aquatic compartments. Recent studies have indicated that this compound can exert biological activity on non-target organisms environmentally exposed. The present study aimed to assess the toxic effects of ERY in Oncorhynchus mykiss after acute and chronic exposures. The here adopted strategy involved exposure to three levels of ERY, the first being similar to concentrations reported to occur in the wild, thus ecologically relevant. Catalase (CAT), total glutathione peroxidase (GPx), glutathione reductase (GRed) activities and lipid peroxidation (TBARS levels) were quantified as oxidative stress biomarkers in gills and liver. Genotoxic endpoints, reflecting different types of genetic damage in blood cells, were also determined, by performing analysis of genetic damage (determination of the genetic damage index, GDI, measured by comet assay) and of erythrocytic nuclear abnormalities (ENAs). The results suggest the occurrence of a mild, but significant, oxidative stress scenario in gills. For acutely exposed organisms, significant alterations were observed in CAT and GRed activities, and also in TBARS levels, which however are modifications with uncertain biological interpretation, despite indicating involvement of an oxidative effect and response. After chronic exposure, a significant decrease of CAT activity, increase of GPx activity and TBARS levels in gills was noticed. In liver, significant decrease in TBARS levels were observed in both exposures. Comet and ENAs assays indicated significant increases on genotoxic damage of O. mykiss, after erythromycin exposures. This set of data (acute and chronic) suggests that erythromycin has the potential to induce DNA strand breaks in blood cells, and demonstrate the induction of chromosome breakage and/or segregational abnormalities. Overall results indicate that both DNA damaging effects induced by

  3. The Exposure Rate Conversion Factor for Nuclear Fallout

    SciTech Connect

    Spriggs, G D

    2009-02-11

    Nuclear fallout is comprised of approximately 2000 radionuclides. About 1000 of these radionuclides are either primary fission products or activated fission products that are created during the burn process. The exposure rate one meter above the surface produced by this complex mixture of radionuclides varies rapidly with time since many of the radionuclides are short-lived and decay numerous times before reaching a stable isotope. As a result, the mixture of radionuclides changes rapidly with time. Using a new code developed at the Lawrence Livermore National Laboratory, the mixture of radionuclides at any given point in time can be calculated. The code also calculates the exposure rate conversion factor (ECF) for all 3864 individual isotopes contained in its database based on the total gamma energy released per decay. Based on the combination of isotope mixture and individual ECFs, the time-dependent variation of the composite exposure rate conversion factor for nuclear fallout can be easily calculated. As example of this new capability, a simple test case corresponding to a 10 kt, uranium-plutonium fuel has been calculated. The results for the time-dependent, composite ECF for this test case are shown in Figure 1. For comparison, we also calculated the composite exposure rate conversion factor using the conversion factors found in Federal Guidance Report No.12 (FGR-12) published by ORNL, which contains the conversion factors for approximately 1000 isotopes. As can be noted from Figure 1, the two functions agree reasonably well at times greater than about 30 minutes. However, they do not agree at early times since FGR-12 does not include all of the short-lived isotopes that are produced in nuclear fallout. It should also be noted that the composite ECF at one hour is 19.7 R/hr per Ci/m{sup 2}. This corresponds to 3148 R/hr per 1 kt per square mile, which agrees reasonably well with the value of 3000 R/hr per 1 kt per square mile as quoted by Glasstone. We have

  4. Human Physiological Responses to Acute and Chronic Cold Exposure

    NASA Technical Reports Server (NTRS)

    Stocks, Jodie M.; Taylor, Nigel A. S.; Tipton, Michael J.; Greenleaf, John E.

    2001-01-01

    When inadequately protected humans are exposed to acute cold, excessive body heat is lost to the environment and unless heat production is increased and heat loss attenuated, body temperature will decrease. The primary physiological responses to counter the reduction in body temperature include marked cutaneous vasoconstriction and increased metabolism. These responses, and the hazards associated with such exposure, are mediated by a number of factors which contribute to heat production and loss. These include the severity and duration of the cold stimulus; exercise intensity; the magnitude of the metabolic response; and individual characteristics such as body composition, age, and gender. Chronic exposure to a cold environment, both natural and artificial, results in physiological alterations leading to adaptation. Three quite different, but not necessarily exclusive, patterns of human cold adaptation have been reported: metabolic, hypothermic, and insulative. Cold adaptation has also been associated with an habituation response, in which there is a desensitization, or damping, of the normal response to a cold stress. This review provides a comprehensive analysis of the human physiological and pathological responses to cold exposure. Particular attention is directed to the factors contributing to heat production and heat loss during acute cold stress, and the ability of humans to adapt to cold environments.

  5. Human Physiological Responses to Acute and Chronic Cold Exposure

    NASA Technical Reports Server (NTRS)

    Stocks, Jodie M.; Taylor, Nigel A. S.; Tipton, Michael J.; Greenleaf, John E.

    2001-01-01

    When inadequately protected humans are exposed to acute cold, excessive body heat is lost to the environment and unless heat production is increased and heat loss attenuated, body temperature will decrease. The primary physiological responses to counter the reduction in body temperature include marked cutaneous vasoconstriction and increased metabolism. These responses, and the hazards associated with such exposure, are mediated by a number of factors which contribute to heat production and loss. These include the severity and duration of the cold stimulus; exercise intensity; the magnitude of the metabolic response; and individual characteristics such as body composition, age, and gender. Chronic exposure to a cold environment, both natural and artificial, results in physiological alterations leading to adaptation. Three quite different, but not necessarily exclusive, patterns of human cold adaptation have been reported: metabolic, hypothermic, and insulative. Cold adaptation has also been associated with an habituation response, in which there is a desensitization, or damping, of the normal response to a cold stress. This review provides a comprehensive analysis of the human physiological and pathological responses to cold exposure. Particular attention is directed to the factors contributing to heat production and heat loss during acute cold stress, and the ability of humans to adapt to cold environments.

  6. Endocrine responses in the rhesus monkey during acute cold exposure

    SciTech Connect

    Lotz, W.G.; Saxton, J.L. )

    1991-03-11

    The authors studied five young male rhesus monkeys (Macaca mulatta), 3.4 to 6.7 kg, to determine the relationship between fluid balance hormones and urine production during acute, dry cold exposure. Each monkey served as its own control in duplicate experimental sessions at 6C or 26C. A 6-h experimental session consisted of 120 min equilibration at 26C, 120 min experimental exposure, and 120 min recovery at 26C. Urinary and venous catheters were inserted on the morning of a session. Rectal (Tre) and skin temperatures were monitored continuously. Blood samples were taken at 0, 30, 60 and 120 min of exposure, and at 60 min postexposure. Plasma was analyzed for arginine vasopressin (AVP), atrial natriuretic factor (ANF), plasma renin activity (PRA), plasma aldosterone (PA), and osmolality. Urine samples were analyzed for osmolality, electrolytes, and creatinine. Mean Tre was 1.6C lower after 120 min at 6C than at 26C. Urine volume and osmolality were not altered by cold exposure, as they are in humans and rats. Vasopressin and PA increased sharply, with mean plasma levels in monkeys exposed to cold more than threefold and tenfold, respectively, the levels in monkeys exposed at 26C. In contrast, ANF, PRA, and plasma osmolality were not significantly changed by cold exposure. The absence of a cold-induced diuresis in the monkey may be related to the marked increase in plasma AVP level.

  7. Mitigation Strategies for Acute Radiation Exposure during Space Flight

    NASA Technical Reports Server (NTRS)

    Hamilton, Douglas R.; Epelman, Slava

    2006-01-01

    While there are many potential risks in a Moon or Mars mission, one of the most important and unpredictable is that of crew radiation exposure. The two forms of radiation that impact a mission far from the protective environment of low-earth orbit, are solar particle events (SPE) and galactic cosmic radiation (GCR). The effects of GCR occur as a long-term cumulative dose that results increased longer-term medical risks such as malignancy and neurological degeneration. Unfortunately, relatively little has been published on the medical management of an acute SPE that could potentially endanger the mission and harm the crew. Reanalysis of the largest SPE in August 1972 revealed that the dose rate was significantly higher than previously stated in the literature. The peak dose rate was 9 cGy h(sup -1) which exceeds the low dose-rate criteria for 25 hrs (National Council on Radiation Protection) and 16 hrs (United Nations Scientific Committee on the Effects of Atomic Radiation). The bone marrow dose accumulated was 0.8 Gy, which exceeded the 25 and 16 hour criteria and would pose a serious medical risk. Current spacesuits would not provide shielding from the damaging effects for an SPE as large as the 1972 event, as increased shielding from 1-5 grams per square centimeters would do little to shield the bone marrow from exposure. Medical management options for an acute radiation event are discussed based on recommendations from the Department of Homeland Security, Centers for Disease Control and evidence-based scientific literature. The discussion will also consider how to define acute exposure radiation safety limits with respect to exploration-class missions, and to determine the level of care necessary for a crew that may be exposed to an SPE similar to August 1972.

  8. Mitigation Strategies for Acute Radiation Exposure during Space Flight

    NASA Technical Reports Server (NTRS)

    Hamilton, Douglas R.; Epelman, Slava

    2006-01-01

    While there are many potential risks in a Moon or Mars mission, one of the most important and unpredictable is that of crew radiation exposure. The two forms of radiation that impact a mission far from the protective environment of low-earth orbit, are solar particle events (SPE) and galactic cosmic radiation (GCR). The effects of GCR occur as a long-term cumulative dose that results increased longer-term medical risks such as malignancy and neurological degeneration. Unfortunately, relatively little has been published on the medical management of an acute SPE that could potentially endanger the mission and harm the crew. Reanalysis of the largest SPE in August 1972 revealed that the dose rate was significantly higher than previously stated in the literature. The peak dose rate was 9 cGy h(sup -1) which exceeds the low-dose-rate criteria for 25 hrs (National Council on Radiation Protection) and 16 hrs (United Nations Scientific Committee on the Effects of Atomic Radiation). The bone marrow dose accumulated was 0.8 Gy, which exceeded the 25 and 16 hour criteria and would pose a serious medical risk. Current spacesuits would not provide shielding from the damaging effects for an SPE as large as the 1972 event, as increased shielding from 1-5 gm/cm(sup 2) would do little to shield the bone marrow from exposure. Medical management options for an acute radiation event are discussed based on recommendations from the Department of Homeland Security, Centers for Disease Control and evidence-based scientific literature. The discussion will also consider how to define acute exposure radiation safety limits with respect to exploration-class missions, and to determine the level of care necessary for a crew that may be exposed to an SPE similar to August 1972.

  9. Mitigation Strategies for Acute Radiation Exposure during Space Flight

    NASA Technical Reports Server (NTRS)

    Hamilton, Douglas R.; Epelman, Slava

    2006-01-01

    While there are many potential risks in a Moon or Mars mission, one of the most important and unpredictable is that of crew radiation exposure. The two forms of radiation that impact a mission far from the protective environment of low-earth orbit, are solar particle events (SPE) and galactic cosmic radiation (GCR). The effects of GCR occur as a long-term cumulative dose that results increased longer-term medical risks such as malignancy and neurological degeneration. Unfortunately, relatively little has been published on the medical management of an acute SPE that could potentially endanger the mission and harm the crew. Reanalysis of the largest SPE in August 1972 revealed that the dose rate was significantly higher than previously stated in the literature. The peak dose rate was 9 cGy h(sup -1) which exceeds the low-dose-rate criteria for 25 hrs (National Council on Radiation Protection) and 16 hrs (United Nations Scientific Committee on the Effects of Atomic Radiation). The bone marrow dose accumulated was 0.8 Gy, which exceeded the 25 and 16 hour criteria and would pose a serious medical risk. Current spacesuits would not provide shielding from the damaging effects for an SPE as large as the 1972 event, as increased shielding from 1-5 gm/cm(sup 2) would do little to shield the bone marrow from exposure. Medical management options for an acute radiation event are discussed based on recommendations from the Department of Homeland Security, Centers for Disease Control and evidence-based scientific literature. The discussion will also consider how to define acute exposure radiation safety limits with respect to exploration-class missions, and to determine the level of care necessary for a crew that may be exposed to an SPE similar to August 1972.

  10. Psychological symptoms and intermittent hypertension following acute microwave exposure

    SciTech Connect

    Forman, S.A.; Holmes, C.K.; McManamon, T.V.; Wedding, W.R.

    1982-11-01

    Two men who were accidently, acutely irradiated with X-band microwave radiation have been followed up clinically for 12 months. Both men developed similar psychological symptoms, which included emotional lability, irritability, headaches, and insomnia. Several months after the incidents, hypertension was diagnosed in both patients. No organic basis for the psychological problems could be found nor could any secondary cause for the hypertension. A similar syndrome following microwave exposure has been described by the East Europeans. The two cases we report, with comparable subjective symptoms and hypertension following a common exposure, provide further strong, circumstantial evidence of cause and effect. A greater knowledge of the mechanisms involved in bioeffects which may be induced by radiofrequency and microwave radiation is definitely needed.

  11. Responses of Hyalella azteca to acute and chronic microplastic exposures.

    PubMed

    Au, Sarah Y; Bruce, Terri F; Bridges, William C; Klaine, Stephen J

    2015-11-01

    Limited information is available on the presence of microplastics in freshwater systems, and even less is known about the toxicological implications of the exposure of aquatic organisms to plastic particles. The present study was conducted to evaluate the effects of microplastic ingestion on the freshwater amphipod, Hyalella azteca. Hyalella azteca was exposed to fluorescent polyethylene microplastic particles and polypropylene microplastic fibers in individual 250-mL chambers to determine 10-d mortality. In acute bioassays, polypropylene microplastic fibers were significantly more toxic than polyethylene microplastic particles; 10-d lethal concentration 50% values for polyethylene microplastic particles and polypropylene microplastic fibers were 4.64 × 10(4) microplastics/mL and 71.43 microplastics/mL, respectively. A 42-d chronic bioassay using polyethylene microplastic particles was conducted to quantify effects on reproduction, growth, and egestion. Chronic exposure to polyethylene microplastic particles significantly decreased growth and reproduction at the low and intermediate exposure concentrations. During acute exposures to polyethylene microplastic particles, the egestion times did not significantly differ from the egestion of normal food materials in the control; egestion times for polypropylene microplastic fibers were significantly slower than the egestion of food materials in the control. Amphipods exposed to polypropylene microplastic fibers also had significantly less growth. The greater toxicity of microplastic fibers than microplastic particles corresponded with longer residence times for the fibers in the gut. The difference in residence time might have affected the ability to process food, resulting in an energetic effect reflected in sublethal endpoints. © 2015 SETAC.

  12. Historical Exposures to Chemicals at the Rocky Flats Nuclear Weapons Plant: A Pilot Retrospective Exposure Assessment

    SciTech Connect

    Robertson, Janeen Denise

    1999-02-01

    In a mortality study of white males who had worked at the Rocky Flats Nuclear Weapons Plant between 1952 and 1979, an increased number of deaths from benign and unspecified intracranial neoplasms was found. A case-control study nested within this cohort investigated the hypothesis that an association existed between brain tumor death and exposure to either internally deposited plutonium or external ionizing radiation. There was no statistically significant association found between estimated radiation exposure from internally deposited plutonium and the development of brain tumors. Exposure by job or work area showed no significant difference between the cohort and the control groups. An update of the study found elevated risk estimates for (1) all lymphopoietic neoplasms, and (2) all causes of death in employees with body burdens greater than or equal to two nanocuries of plutonium. There was an excess of brain tumors for the entire cohort. Similar cohort studies conducted on worker populations from other plutonium handling facilities have not yet shown any elevated risks for brain tumors. Historically, the Rocky Flats Nuclear Weapons Plant used large quantities of chemicals in their production operations. The use of solvents, particularly carbon tetrachloride, was unique to Rocky Flats. No investigation of the possible confounding effects of chemical exposures was done in the initial studies. The objectives of the present study are to (1) investigate the history of chemical use at the Rocky Flats facility; (2) locate and analyze chemical monitoring information in order to assess employee exposure to the chemicals that were used in the highest volume; and (3) determine the feasibility of establishing a chemical exposure assessment model that could be used in future epidemiology studies.

  13. Pediatric acute lymphoblastic leukemia and exposure to pesticides.

    PubMed

    Soldin, Offie P; Nsouli-Maktabi, Hala; Nsouly-Maktabi, Hala; Genkinger, Jeanine M; Loffredo, Christopher A; Ortega-Garcia, Juan Antonio; Colantino, Drew; Barr, Dana B; Luban, Naomi L; Shad, Aziza T; Nelson, David

    2009-08-01

    Organophosphates are pesticides ubiquitous in the environment and have been hypothesized as one of the risk factors for acute lymphoblastic leukemia (ALL). In this study, we evaluated the associations of pesticide exposure in a residential environment with the risk for pediatric ALL. This is a case-control study of children newly diagnosed with ALL, and their mothers (n = 41 child-mother pairs) recruited from Georgetown University Medical Center and Children's National Medical Center in Washington, DC, between January 2005 and January 2008. Cases and controls were matched for age, sex, and county of residence. Environmental exposures were determined by questionnaire and by urinalysis of pesticide metabolites using isotope dilution gas chromatography-high-resolution mass spectrometry. We found that more case mothers (33%) than controls (14%) reported using insecticides in the home (P < 0.02). Other environmental exposures to toxic substances were not significantly associated with the risk of ALL. Pesticide levels were higher in cases than in controls (P < 0.05). Statistically significant differences were found between children with ALL and controls for the organophosphate metabolites diethylthiophosphate (P < 0.03) and diethyldithiophosphate (P < 0.05). The association of ALL risk with pesticide exposure merits further studies to confirm the association.

  14. Pediatric Acute Lymphoblastic Leukemia and Exposure to Pesticides

    PubMed Central

    Soldin, Offie P.; Nsouly-Maktabi, Hala; Genkinger, Jeanine M.; Loffredo, Christopher A.; Ortega-Garcia, Juan Antonio; Colantino, Drew; Barr, Dana B.; Luban, Naomi L.; Shad, Aziza T.; Nelson, David

    2013-01-01

    Organophosphates are pesticides ubiquitous in the environment and have been hypothesized as one of the risk factors for acute lymphoblastic leukemia (ALL). In this study, we evaluated the associations of pesticide exposure in a residential environment with the risk for pediatric ALL. This is a case–control study of children newly diagnosed with ALL, and their mothers (n = 41 child–mother pairs) were recruited from Georgetown University Medical Center and Children's National Medical Center in Washington, DC, between January 2005 and January 2008. Cases and controls were matched for age, sex, and county of residence. Environmental exposures were determined by questionnaire and by urinalysis of pesticide metabolites using isotope dilution gas chromatography–high-resolution mass spectrometry. We found that more case mothers (33%) than controls (14%) reported using insecticides in the home (P < 0.02). Other environmental exposures to toxic substances were not significantly associated with the risk of ALL. Pesticide levels were higher in cases than in controls (P < 0.05). Statistically significant differences were found between children with ALL and controls for the organophosphate metabolites diethylthiophosphate (P < 0.03) and diethyldithiophosphate (P < 0.05). The association of ALL risk with pesticide exposure merits further studies to confirm the association. PMID:19571777

  15. Secondhand smoke exposure induces acutely airway acidification and oxidative stress.

    PubMed

    Kostikas, Konstantinos; Minas, Markos; Nikolaou, Eftychia; Papaioannou, Andriana I; Liakos, Panagiotis; Gougoura, Sofia; Gourgoulianis, Konstantinos I; Dinas, Petros C; Metsios, Giorgos S; Jamurtas, Athanasios Z; Flouris, Andreas D; Koutedakis, Yiannis

    2013-02-01

    Previous studies have shown that secondhand smoke induces lung function impairment and increases proinflammatory cytokines. The aim of the present study was to evaluate the acute effects of secondhand smoke on airway acidification and airway oxidative stress in never-smokers. In a randomized controlled cross-over trial, 18 young healthy never-smokers were assessed at baseline and 0, 30, 60, 120, 180 and 240 min after one-hour secondhand smoke exposure at bar/restaurant levels. Exhaled NO and CO measurements, exhaled breath condensate collection (for pH, H(2)O(2) and NO(2)(-)/NO(3)(-) measurements) and spirometry were performed at all time-points. Secondhand smoke exposure induced increases in serum cotinine and exhaled CO that persisted until 240 min. Exhaled breath condensate pH decreased immediately after exposure (p < 0.001) and returned to baseline by 180 min, whereas H(2)O(2) increased at 120 min and remained increased at 240 min (p = 0.001). No changes in exhaled NO and NO(2)/NO(3) were observed, while decreases in FEV(1) (p < 0.001) and FEV(1)/FVC (p < 0.001) were observed after exposure and returned to baseline by 180 min. A 1-h exposure to secondhand smoke induced airway acidification and increased airway oxidative stress, accompanied by significant impairment of lung function. Despite the reversal in EBC pH and lung function, airway oxidative stress remained increased 4 h after the exposure. Clinical trial registration number (EudraCT): 2009-013545-28. Copyright © 2012 Elsevier Ltd. All rights reserved.

  16. Effects of Acute Exposures to Carbon Dioxide upon Cognitive Functions

    NASA Technical Reports Server (NTRS)

    Ryder, V. E.; Scully, R. R.; Alexander, D. J.; Lam, C. W.; Young, M.; Satish, U.; Basner, M.

    2017-01-01

    Carbon dioxide (CO2) originates from human metabolism and typically remains about 10-fold higher in concentration on the International Space Station (ISS) than at the earth's surface. There have been recurring complaints by crew members of episodes of "mental viscosity" adversely affecting their performance, and there is evidence from the ISS that associates CO2 levels with reports of headaches by crewmembers. Consequently, flight rules have been employed to control CO2 below 3 mm Hg, which is well below the existing Spacecraft Maximum Allowable Concentration (SMAC) of 10 mm Hg for 24-hour exposures, and 5.3 mm Hg for exposures of 7 to 180 days. Headaches, while sometime debilitating themselves, are also symptoms that can provide evidence that physiological defense mechanisms have been breached, and there is evidence that CO2 has effects at levels below the threshold for headaches. This concern appears to be substantiated in reports that CO2 at concentrations below 2 mm Hg substantially reduced some cognitive functions that are associated with the ability to make complex decisions in conditions that are characterized by volatility, uncertainty, complexity, ambiguity, and delayed feedback. These are conditions that could be encountered by crews in off-nominal situations or during the first missions beyond low earth orbit. Therefore, we set out to determine if decision-making under volatile, uncertain, confusing and ambiguous circumstances, where feedback is delayed or absent, is correlated with low levels of CO2 during acute exposures (several hours) in crew-like subjects and to determine if additional cognitive domains are sensitive to concentrations of CO2 at, or below, current ISS levels by using a test battery that is currently available onboard ISS. We enrolled 22 volunteers (8 females, 14 males) between the ages of 30-55 (38.8 +/- 7.0) years whose training and professional experience reflect that of the astronaut corps. Subjects were divided among 4 study

  17. Inhalation exposure system used for acute and repeated-dose methyl isocyanate exposures of laboratory animals.

    PubMed

    Adkins, B; O'Connor, R W; Dement, J M

    1987-06-01

    Laboratory animals were exposed by inhalation for 2 hr/day (acute) or 6 hr/day (four consecutive days, repeated dose) to methyl isocyanate (MIC). Exposures were conducted in stainless steel and glass inhalation exposure chambers placed in stainless steel, wire mesh cages. MIC was delivered with nitrogen via stainless steel and Teflon supply lines. Chamber concentrations ranged from 0 to 60 ppm and were monitored continuously with infrared spectrophotometers to 1 ppm and at 2-hr intervals to 20 ppb with a high performance liquid chromatograph equipped with a fluorescence detector. Other operational parameters monitored on a continuous basis included chamber temperature (20-27 degrees C), relative humidity (31-64%), static (transmural) pressure (-0.3 in.), and flow (300-500 L/min). The computer-assistance system interfaced with the inhalation exposure laboratory is described in detail, including the analytical instrumentation calibration system used throughout this investigation.

  18. Acute and chronic cadmium exposure promotes E-cadherin degradation in MCF7 breast cancer cells.

    PubMed

    Ponce, Esmeralda; Louie, Maggie C; Sevigny, Mary B

    2015-10-01

    Cadmium is an environmental carcinogen that usually enters the body at minute concentrations through diet or cigarette smoke and bioaccumulates in soft tissues. In past studies, cadmium has been shown to contribute to the development of more aggressive cancer phenotypes including increased cell migration and invasion. This study aims to determine if cadmium exposure-both acute and chronic-contributes to breast cancer progression by interfering with the normal functional relationship between E-cadherin and β-catenin. An MCF7 breast cancer cell line (MCF7-Cd) chronically exposed to 10(-7)  M CdCl2 was previously developed and used as a model system to study chronic exposures, whereas parental MCF7 cells exposed to 10(-6)  M CdCl2 for short periods of time were used to study acute exposures. Cadmium exposure of MCF7 cells led to the degradation of the E-cadherin protein via the ubiquitination pathway. This resulted in fewer E-cadherin/β-catenin complexes and the relocation of active β-catenin to the nucleus, where it interacted with transcription factor TCF-4 to modulate gene expression. Interestingly, only cells chronically exposed to cadmium showed a significant decrease in the localization of β-catenin to the plasma membrane and an increased distance between cells. Our data suggest that cadmium exposure promotes breast cancer progression by (1) down-regulating E-cadherin, thus decreasing the number of E-cadherin/β-catenin adhesion complexes, and (2) enhancing the nuclear translocation of β-catenin to increase expression of cancer-promoting proteins (i.e., c-Jun and cyclin D1).

  19. Acute exposure of rabbits to diphenyl diselenide: a toxicological evaluation.

    PubMed

    Straliotto, Marcos Raniel; Mancini, Gianni; de Oliveira, Jade; Nazari, Evelise Maria; Müller, Yara Maria Rauh; Dafre, Alcir; Ortiz, Susana; Silva, Edson Luiz; Farina, Marcelo; Latini, Alexandra; Rocha, João Batista Teixeira; de Bem, Andreza Fabro

    2010-11-01

    The simple organoselenium compound diphenyl diselenide (PhSe)(2) is a promising new pharmacological agent. However, few toxicological evaluations of this molecule have been reported. We evaluated the effects of acute administration of (PhSe)(2) on toxicological parameters in rabbits. Adult New Zealand rabbits were exposed to (PhSe)(2) (5-500 micromol kg(-1) , intraperitoneally) once a day for 5 days. Exposure to 500 micromol kg(-1) caused 85% mortality. Exposure to 50 micromol kg(-1) of (PhSe)(2) increased the glutathione levels in the hippocampus, kidney, heart, muscle and blood, whereas lipoperoxidation (TBARS) decreased in the cerebellum and kidney after exposure to 5 micromol kg(-1) . The activity of glutathione peroxidase increased in the heart and muscle of rabbits treated with 50 micromol kg(-1) of (PhSe)(2) and glutathione reductase activity was reduced in the cerebellum, cerebral cortex and kidney. Treatment with (PhSe)(2) reduced the activity of δ-aminolevulinate dehydratase in the hippocampus and increased this activity in the heart, but did not alter the activity of complexes I and II of the respiratory chain in the liver and brain. Hepatic and renal biochemical and histological parameters were not modified by (PhSe)(2) and apoptosis was not detected in these tissues; however, the hepatic cells tended to accumulate fat vacuoles. These results indicated that acute toxicology to (PhSe)(2) in rabbit is dependent on the dose, which should motivate further experiments on the therapeutic properties of this compound. 2010 John Wiley & Sons, Ltd.

  20. Acute effects of acrolein in human volunteers during controlled exposure

    PubMed Central

    Dwivedi, Aishwarya M.; Johanson, Gunnar; Lorentzen, Johnny C.; Palmberg, Lena; Sjögren, Bengt; Ernstgård, Lena

    2015-01-01

    Abstract Context: Acrolein is a reactive aldehyde mainly formed by combustion. The critical effect is considered to be irritation of the eyes and airways; however, the scarce data available make it difficult to assess effect levels. Objective: The aim of the study was to determine thresholds for acute irritation for acrolein. Methods: Nine healthy volunteers of each sex were exposed at six occasions for 2 h at rest to: clean air, 15 ppm ethyl acetate (EA), and 0.05 ppm and 0.1 ppm acrolein with and without EA (15 ppm) to mask the potential influence of odor. Symptoms related to irritation and central nervous system effects were rated on 100-mm Visual Analogue Scales. Results: The ratings of eye irritation were slightly but significantly increased during exposure to acrolein in a dose-dependent manner (p < 0.001, Friedman test) with a median rating of 8 mm (corresponding to “hardly at all”) at the 0.1 ppm condition and with no influence from EA. No significant exposure-related effects were found for pulmonary function, or nasal swelling, nor for markers of inflammation and coagulation in blood (IL-6, C-reactive protein, serum amyloid A, fibrinogen, factor VIII, von Willebrand factor, and Clara cell protein) or induced sputum (cell count, differential cell count, IL-6 and IL-8). Blink frequency recorded by electromyography was increased during exposure to 0.1 ppm acrolein alone but not during any of the other five exposure conditions. Conclusion: Based on subjective ratings, the present study showed minor eye irritation by exposure to 0.1 ppm acrolein. PMID:26635308

  1. Self-reported acute health symptoms and exposure to companion animals

    EPA Science Inventory

    Background: In order to understand the etiological burden of disease associated with acute health symptoms (e.g. gastrointestinal [GI], respiratory, dermatological), it is important to understand how common exposures influence these symptoms. Exposures to familiar and unfamiliar ...

  2. Self-reported acute health symptoms and exposure to companion animals

    EPA Science Inventory

    Background: In order to understand the etiological burden of disease associated with acute health symptoms (e.g. gastrointestinal [GI], respiratory, dermatological), it is important to understand how common exposures influence these symptoms. Exposures to familiar and unfamiliar ...

  3. Acute exposure to UVB has a more profound effect on plant genome stability than chronic exposure.

    PubMed

    Boyko, Alex; Greer, Michael; Kovalchuk, Igor

    2006-12-01

    Environmental factors that damage DNA have various lengths of exposure and intensity levels. Although the results of increasing the intensity of a DNA damaging agent is often predictable, it is not clear whether the stage during development when the exposure is received has any influence on the amount of DNA damage. In this paper we analyzed the influence of UVB on the stability of Arabidopsis thaliana and the Nicotiana tabacum genomes. Our experiments showed that the acute exposure to UVB produces a significantly greater increase in homologous recombination frequency (HRF) and recombination rate (RR) compared with that produced by chronic exposure. The increase in HRF showed a positive correlation with UVB dose and a negative correlation with plant age. In other words, as the UVB dose was increased, there was a concomitant increase in HRF. Conversely, older plants had a lower HRF increase as compared to younger plants. Our experiments suggest that exposure to UVB makes the most significant impact on genome stability during the early stages of plant development.

  4. Infant acute leukemia and maternal exposures during pregnancy.

    PubMed

    Pombo-de-Oliveira, Maria S; Koifman, Sergio

    2006-12-01

    Infant acute leukemia (IAL) has a unique profile characterized by the high incidence of translocations involving the MLL gene located at the 11q23 region. To test the potential role of intrauterine and perinatal factors linked to the risk of IAL development, a hospital-based case-control study was conducted in different cities of Brazil. A total of 202 children (ages 0-21 months) with newly diagnosed IAL was enrolled (1999-2005), and 440 age-matched controls were selected from the same hospitals wherein IAL cases were treated. A statistically significant association between maternal use of hormones during pregnancy and IAL was observed [odds ratio (OR), 8.76; 95% confidence interval (95% CI), 2.85-26.93] in a multivariable analysis. The association of certain exposures during pregnancy (hormones, dipyrone, metronidazole, and misoprostol) and MLL gene rearrangements was tested using a case-case approach. Despite the lack of statistical significance, the magnitude of the OR for maternal exposure to dipyrone (OR, 1.45; 95% CI, 0.75-2.86), metronidazole (OR, 1.72; 95% CI, 0.64-4.58), quinolones (OR, 2.25; 95% CI, 0.70-25.70), and hormones (OR, 1.88; 95% CI, 0.50-7.01) may suggest the occurrence of interactions between such maternal exposures during pregnancy and MLL rearrangements, yielding into IAL development. The strong and statistically significant association between IAL and estrogen exposure during pregnancy observed in this study deserves further investigation to investigate its role in intrauterine leukemogenesis.

  5. Dental fractures on acute exposure to high altitude.

    PubMed

    Zadik, Yehuda; Einy, Shmuel; Pokroy, Russell; Bar Dayan, Yaron; Goldstein, Liav

    2006-06-01

    There is little in the literature on dental restoration breakage in the aviation environment since reports of problems in combat aviators in War World II. We report two cases of dental fractures during acute exposure to a hypobaric environment. Case 1 was a young officer who suffered an amalgam restoration breakage during a 25,000-ft decompression chamber simulation. Case 2 occurred in an experienced aviator who had a tooth cusp fracture in a molar with a defective amalgam restoration during an unpressurized helicopter flight to 18,000 ft. In both cases, after removing the defective fillings, deep secondary caries were found; both teeth were successfully restored. Because hard-tissue tooth fracture during a high-altitude flight is a rare event, few flight surgeons or dentists are familiar with this phenomenon. We recommend regular dental examinations with careful assessment of previous dental restorations in aircrew subject to decompression.

  6. Effect of acute smoke exposure on hepatic protein synthesis.

    PubMed

    Garrett, R J; Jackson, M A

    1979-05-01

    In vivo hepatic protein synthesis was monitored in female rats under control and smoke-exposed conditions. During the 15 min period after i.v. administration of [3H]proline protein synthesis was 206 +/- 35 nmol of proline per mg of DNA for sham-control animals. When animals were subjected to acute exposure to cigarette smoke, protein synthesis was inhibited and the extent of inhibition was positively correlated with the dosage of smoke (32%, 15 puffs; 66%, 60 puffs). The inhibitory effect of whole smoke on protein synthesis was unaltered by passing the smoke through either charcoal or cambridge filters. Carbon monoxide in smoke is not removed by either type of filter. At a level comparable to that in cigarette smoke carbon monoxide depressed hepatic protein synthesis to the same extent as did whole or filtered smoke.

  7. Acute health effects of accidental chlorine gas exposure

    PubMed Central

    2014-01-01

    Objectives This study was conducted to report the course of an accidental release of chlorine gas that occurred in a factory in Gumi-si, South Korea, on March 5, 2013. We describe the analysis results of 2 patients hospitalized because of chlorine-induced acute health problems, as well as the clinical features of 209 non-hospitalized patients. Methods We analyzed the medical records of the 2 hospitalized patients admitted to the hospital, as well as the medical records and self-report questionnaires of 209 non-hospitalized patients completed during outpatient treatment. Results Immediately after the exposure, the 2 hospitalized patients developed acute asthma-like symptoms such as cough and dyspnea, and showed restrictive and combined pattern ventilatory defects on the pulmonary function test. The case 1 showed asthma-like symptoms over six months and diurnal variability in peak expiratory flow rate was 56.7%. In case 2, his FEV1 after treatment (93%) increased by 25% compared to initial FEV1 (68%). Both cases were diagnosed as chlorine-induced reactive airways dysfunction syndrome (RADS) on the basis of these clinical features. The most frequent chief complaints of the 209 non-hospitalized patients were headache (22.7%), followed by eye irritation (18.2%), nausea (11.2%), and sore throat (10.8%), with asymptomatic patients accounting for 36.5%. The multiple-response analysis of individual symptom revealed headache (42.4%) to be the most frequent symptom, followed by eye irritation (30.5%), sore throat (30.0%), cough (29.6%), nausea (27.6%), and dizziness (27.3%). Conclusions The 2 patients hospitalized after exposure to chlorine gas at the leakage site showed a clinical course corresponding to RADS. All of the 209 non-hospitalized patients only complained of symptoms of the upper airways and mucous membrane irritation. PMID:25852940

  8. Acute arsenic exposure treated with oral D-penicillamine

    SciTech Connect

    Watson, W.A.; Veltri, J.C.; Metcalf, T.J.

    1981-06-01

    Arsenic trioxide (As2O3) is the arsenic compound most commonly implicated in acute toxic exposures. The toxicity of As2O3 is a function of the preparation's particle size and solubility. A 16-month-old female presented at a local emergency room with a history of acute ingestion of As2O3 obtained from a commonly available pesticide. Classic gastrointestinal symptoms of arsenic toxicity were exhibited shortly after ingestion; however, aggressive decontamination followed by early chelation therapy resulted in the cessation of toxic manifestations and an uneventful recovery. Oral chelation therapy with D-penicillamine has rarely been reported as an effective agent in the treatment of arsenic poisoning. The case reported herein is further documentation that D-penicillamine is effective in increasing the mobilization of arsenic. The authors also recommend that products containing arsenic compounds should not be used where children may come in contact with them until the Environmental Protection Agency's child resistant packaging regulations become effective.

  9. Sildenafil does not Improve Exercise Capacity under Acute Hypoxia Exposure.

    PubMed

    Toro-Salinas, A H; Fort, N; Torrella, J R; Pagès, T; Javierre, C; Viscor, G

    2016-09-01

    The increase in pulmonary arterial pressure (PAP) due to hypoxic pulmonary vasoconstriction (HPV) could be a limiting factor for physical performance during hypoxic exposure. Sildenafil has been shown to reduce PAP in situations of moderate or severe hypoxia, and consequently its role as an ergogenic aid and even a possible doping substance must be considered. We performed a double-blind crossover study to determine the effects of sildenafil on cardiovascular, respiratory and metabolic parameters in normoxia and during acute exposure to hypobaric hypoxia (4 000 m) at rest and during maximal and submaximal (60% VO2 max) exercise tests. One hour before testing started, sildenafil (100 mg) or a placebo was orally administered to 11 volunteers. In normoxic conditions, sildenafil did not affect performance. Similarly, no significant differences were found in cardiovascular and respiratory parameters in hypoxic conditions at rest or during exercise. The use of sildenafil to improve physical performance in non-acclimatized subjects is not supported by our data. © Georg Thieme Verlag KG Stuttgart · New York.

  10. Acute skin lesions due to localized ``hot particle`` radiation exposures

    SciTech Connect

    Baum, J.W.; Carsten, A.L.; Kaurin, D.G.L.; Schaefer, C.W.

    1996-06-01

    Purpose of the studies was to determine incidence and severity of lesions resulting from localized deposition of dose to the skin from small (<0.5 mm) discrete radioactive particles. Hanford mini-swine were exposed to localized doses from 0.2 to over 600 Gy (averaged over 1 cm{sup 2} at 70{mu}m depth) from isotopes having max beta particle energies from about 0.3-3 MeV. Incidence of erythema and scabs (indicating ulceration) were scored routinely for up to 71 days post-irradiation. Responses followed normal probability distributions, and thus, no true threshold could be defined. Ten and 50% incidence rates were deduced using probit analyses. Lowest dose producing 10% incidence was about 1 Gy for exposures to Yb-175 (0.5 MeV max energy) beta particles. Severity of lesions was estimated using diameters and persistence. From preliminary considerations of probability of induction, size, and persistence of acute lesions, a special limit for hot particle exposures in the range of 5-50 Gy may be reasonable, with an action level between about 1 Gy and the limit.

  11. Predictors of individual differences in acute response to ozone exposure

    SciTech Connect

    McDonnell, W.F.; Muller, K.E.; Bromberg, P.A.; Shy, C.M. )

    1993-04-01

    The purpose of this study was to identify personal characteristics that predict individual differences in acute FEV1 response to ozone exposure. Response and predictor data were collected on 290 white male volunteers 18 to 32 yr of age who were each exposed to one of six concentrations of ozone between 0.0 and 0.40 part per million. The sample was divided into an exploratory sample of 96 and a confirmatory sample of 194 subjects. Exploratory analysis indicated that ozone, age, and several other variables explained a significant proportion of the variance in response. In the confirmatory sample, only age and ozone concentration predicted FEV1 decrement. For the combined sample ozone explained 31% of the variance, with age accounting for an additional 4%. The model predicted a decreasing response with increasing age for all nonzero ozone concentrations. For exposure to 0.40 ppm, the model predicts decrements in FEV1 of 1.07 and 0.47 L for 18- and 30-yr-old subjects, respectively. We concluded that for white male subjects age was a significant predictor of response, with older subjects being less responsive to ozone. Furthermore, we demonstrated that exploratory analysis without control of type I statistical error rates may result in apparent findings that cannot be replicated.

  12. Acute acid exposure increases rabbit esophageal cell proliferation.

    PubMed

    Carpizo, D R; Reaka, A J; Glaws, W R; Pooley, N; Schmidt, L; Halline, A G; Goldstein, J L; Layden, T J

    1998-02-01

    In the present study we examined whether an acute infusion of HCl into the esophagus of rabbits would cause an increase in esophageal cellular proliferation independent of morphologic evidence of cell injury. To examine this question, the distal two thirds of the rabbit esophagus was infused for 1 hour with either 40 mmol/L HCl or NSS (control), and cellular proliferation was studied 24 and 48 hours later by using bromodeoxyuridine (BrDu) to label the nuclei of dividing cells and ornithine decarboxylase (ODC) enzyme activity as a biochemical index of cell division. Although there was no gross or microscopic evidence of cell necrosis or mucosal inflammation 24 hours after H+ infusion, BrDu labeling of basal cell nuclei was significantly greater 24 hours after H+ infusion (31%+/-6%) as compared with that in control animals infused with NSS (15%+/-4%). This increase in labeling index was paralleled by a threefold greater ODC enzyme activity at 24 hours with H+ infusion. Rete pegs were infrequent in control tissues (4+/-4 rete pegs per 100 microm of esophageal length) or in animals examined 24 hours after acid exposure (4+/-2 rete pegs per 100 microm). However, rete pegs were very prominent 48 hours after acid infusion (22+/-6 rete pegs per 100 microm). A short exposure to acid can cause a significant increase in mucosal proliferation independent of injury, suggesting that esophageal cell acidification either directly or indirectly acts as a tissue mitogen.

  13. Biomarkers of acute respiratory allergen exposure: Screening for sensitization potential

    SciTech Connect

    Pucheu-Haston, Cherie M.; Copeland, Lisa B.; Vallanat, Beena; Boykin, Elizabeth; Ward, Marsha D.W.

    2010-04-15

    Effective hazard screening will require the development of high-throughput or in vitro assays for the identification of potential sensitizers. The goal of this preliminary study was to identify potential biomarkers that differentiate the response to allergens vs non-allergens following an acute exposure in naive individuals. Female BALB/c mice received a single intratracheal aspiration exposure to Metarhizium anisopliae crude antigen (MACA) or bovine serum albumin (BSA) in Hank's Balanced Salt Solution (HBSS) or HBSS alone. Mice were terminated after 1, 3, 6, 12, 18 and 24 h. Bronchoalveolar lavage fluid (BALF) was evaluated to determine total and differential cellularity, total protein concentration and LDH activity. RNA was isolated from lung tissue for microarray analysis and qRT-PCR. MACA administration induced a rapid increase in BALF neutrophils, lymphocytes, eosinophils and total protein compared to BSA or HBSS. Microarray analysis demonstrated differential expression of genes involved in cytokine production, signaling, inflammatory cell recruitment, adhesion and activation in 3 and 12 h MACA-treated samples compared to BSA or HBSS. Further analyses allowed identification of approx 100 candidate biomarker genes. Eleven genes were selected for further assessment by qRT-PCR. Of these, 6 demonstrated persistently increased expression (Ccl17, Ccl22, Ccl7, Cxcl10, Cxcl2, Saa1), while C3ar1 increased from 6-24 h. In conclusion, a single respiratory exposure of mice to an allergenic mold extract induces an inflammatory response which is distinct in phenotype and gene transcription from the response to a control protein. Further validation of these biomarkers with additional allergens and irritants is needed. These biomarkers may facilitate improvements in screening methods.

  14. Flight Performance During Exposure to Acute Hypobaric Hypoxia.

    PubMed

    Steinman, Yuval; van den Oord, Marieke H A H; Frings-Dresen, Monique H W; Sluiter, Judith K

    2017-08-01

    The purpose of the present study was to examine the influence of hypobaric hypoxia (HH) on a pilot's flight performance during exposure to simulated altitudes of 91, 3048, and 4572 m (300, 10,000, and 15,000 ft) and to monitor the pilot's physiological reactions. In a single-blinded counter-balanced design, 12 male pilots were exposed to HH while flying in a flight simulator that had been placed in a hypobaric chamber. Flight performance of the pilots, pilot's alertness level, Spo2, heart rate (HR), minute ventilation (VE), and breathing frequency (BF) were measured. A significant difference was found in Flight Profile Accuracy (FPA) between the three altitudes. Post hoc analysis showed no significant difference in performance between 91 m and 3048 m. A trend was observed at 4572 m, suggesting a decrease in flight performance at that altitude. Significantly lower alertness levels were observed at the start of the flight at 4572 m compared to 91 m, and at the end of the flight at 4572 m compared to the start at that altitude. Spo2 and BF decreased, and HR increased significantly with altitude. The present study did not provide decisive evidence for a decrease in flight performance during exposure to simulated altitudes of 3048 and 4572 m. However, large interindividual variation in pilots' flight performance combined with a gradual decrease in alertness levels observed in the present study puts into question the ability of pilots to safely fly an aircraft while exposed to these altitudes without supplemental oxygen.Steinman Y, van den Oord MHAH, Frings-Dresen MHW, Sluiter JK. Flight performance during exposure to acute hypobaric hypoxia. Aerosp Med Hum Perform. 2017; 88(8):760-767.

  15. Injury to skeletal muscle of mice following acute and sub-acute pregabalin exposure

    PubMed Central

    Moshiri, Mohammad; Moallem, Seyed Adel; Attaranzadeh, Armin; Saberi, Zahra; Etemad, Leila

    2017-01-01

    Objective(s): Pregabalin (PGB) is a new antiepileptic drug that has received FDA approval for patient who suffers from central neuropathic pain, partial seizures, generalized anxiety disorder, fibromyalgia and sleep disorders. This study was undertaken to evaluate the possible adverse effects of PGB on the muscular system of mice. Materials and Methods: To evaluate the effect of PGB on skeletal muscle, the animals were exposed to a single dose of 1, 2 or 5 g /kg or daily doses of 20, 40 or 80 mg/kg for 21 days, intraperitoneally (IP). Twaenty-four hr after the last drug administration, all animals were sacrificed. The level of fast-twitch skeletal muscle troponin I and CK-MM activity were evaluated in blood as an indicator of muscle injury. Skeletal muscle pathological findings were also reported as scores ranging from 1 to 3 based on the observed lesion. Results: In the acute and sub-acute toxicity assay IP injection of PGB significantly increased the activity and levels of CK-MM and fsTnI compared to the control group. Sub-acute exposure to PGB caused damages that include muscle atrophy, infiltration of inflammatory cells and cell degeneration. Conclusion: PGB administration especially in long term care causes muscle atrophy with infiltration of inflammatory cells and cell degeneration. The fsTnI and CK-MM are reliable markers in PGB-related muscle injury. The exact mechanisms behind the muscular damage are unclear and necessitate further investigations. PMID:28392896

  16. Carryover Effects of Acute DEHP Exposure on Ovarian Function and Oocyte Developmental Competence in Lactating Cows

    PubMed Central

    Kalo, Dorit; Hadas, Ron; Furman, Ori; Ben-Ari, Julius; Maor, Yehoshua; Patterson, Donald G.; Tomey, Cynthia; Roth, Zvi

    2015-01-01

    We examined acute exposure of Holstein cows to di(2-ethylhexyl) phthalate (DEHP) and its carryover effects on ovarian function and oocyte developmental competence. Synchronized cows were tube-fed with water or 100 mg/kg DEHP per day for 3 days. Blood, urine and milk samples were collected before, during and after DEHP exposure to examine its clearance pattern. Ovarian follicular dynamics was monitored through an entire estrous cycle by ultrasonographic scanning. Follicular fluids were aspirated from the preovulatory follicles on days 0 and 29 of the experiment and analyzed for phthalate metabolites and estradiol concentration. The aspirated follicular fluid was used as maturation medium for in-vitro embryo production. Findings revealed that DEHP impairs the pattern of follicular development, with a prominent effect on dominant follicles. The diameter and growth rate of the first- and second-wave dominant follicles were lower (P < 0.05) in the DEHP-treated group. Estradiol concentration in the follicular fluid was lower in the DEHP-treated group than in controls, and associated with a higher number of follicular pathologies (follicle diameter >25 mm). The pattern of growth and regression of the corpus luteum differed between groups, with a lower volume in the DEHP-treated group (P < 0.05). The follicular fluid aspirated from the DEHP-treated group, but not the controls, contained 23 nM mono(2-ethylhexyl) phthalate. Culturing of cumulus oocyte complexes in the follicular fluid aspirated from DEHP-treated cows reduced the proportion of oocytes progressing to the MII stage, and the proportions of 2- to 4-cell-stage embryos (P < 0.04) and 7-day blastocysts (P < 0.06). The results describe the risk associated with acute exposure to DEHP and its deleterious carryover effects on ovarian function, nuclear maturation and oocyte developmental competence. PMID:26154164

  17. Acute and chronic poisoning from residential exposures to elemental mercury--Michigan, 1989-1990

    SciTech Connect

    Not Available

    1991-06-14

    From May 1989 through November 1990, eight episodes of elemental mercury exposure in private residences or schools in the United States were reported to the Agency for Toxic Substances and Disease Registry (ATSDR). The case studies in this report document two of these episodes (both in Michigan) of residential mercury poisoning--one involving acute mercury exposure, and the other, chronic exposure to elemental mercury. These episodes illustrate the differing clinical and toxicologic manifestations of acute and chronic mercury poisoning.

  18. QSAR Modeling of Rat Acute Toxicity by Oral Exposure

    PubMed Central

    Zhu, Hao; Martin, Todd M.; Ye, Lin; Sedykh, Alexander; Young, Douglas M.; Tropsha, Alexander

    2009-01-01

    Few Quantitative Structure-Activity Relationship (QSAR) studies have successfully modeled large, diverse rodent toxicity endpoints. In this study, a comprehensive dataset of 7,385 compounds with their most conservative lethal dose (LD50) values has been compiled. A combinatorial QSAR approach has been employed to develop robust and predictive models of acute toxicity in rats caused by oral exposure to chemicals. To enable fair comparison between the predictive power of models generated in this study versus a commercial toxicity predictor, TOPKAT (Toxicity Prediction by Komputer Assisted Technology), a modeling subset of the entire dataset was selected that included all 3,472 compounds used in the TOPKAT’s training set. The remaining 3,913 compounds, which were not present in the TOPKAT training set, were used as the external validation set. QSAR models of five different types were developed for the modeling set. The prediction accuracy for the external validation set was estimated by determination coefficient R2 of linear regression between actual and predicted LD50 values. The use of the applicability domain threshold implemented in most models generally improved the external prediction accuracy but expectedly led to the decrease in chemical space coverage; depending on the applicability domain threshold, R2 ranged from 0.24 to 0.70. Ultimately, several consensus models were developed by averaging the predicted LD50 for every compound using all 5 models. The consensus models afforded higher prediction accuracy for the external validation dataset with the higher coverage as compared to individual constituent models. The validated consensus LD50 models developed in this study can be used as reliable computational predictors of in vivo acute toxicity. PMID:19845371

  19. Acute exposure to acid fog. Effects on mucociliary clearance

    SciTech Connect

    Laube, B.L.; Bowes, S.M. III; Links, J.M.; Thomas, K.K.; Frank, R. )

    1993-05-01

    Submicrometric sulfuric acid (H2SO4) aerosol can affect mucociliary clearance without eliciting irritative symptoms or changes in pulmonary function. The effect of larger fog droplets containing H2SO4 on mucociliary clearance is unknown. We quantified mucociliary clearance from the trachea (n = 4) and small airways (n = 7) of young healthy male adults after an acute exposure to H2SO4 fog (MMAD = 10.3 microns; pH = 2.0; liquid water content = 481 +/- 65 mg/m3; osmolarity = 30 mOsm). Acid fog (AF) or saline fog (SF) (10.9 microns; 492 +/- 116 mg/m3; 30 mOsm) was administered for 40 min of unencumbered breathing (no mouth-piece) at rest and for 20 min of exercise sufficient to produce oronasal breathing. Fog exposures were followed by a methacholine (MCh) challenge (a measure of airway reactivity) or inhalation of technetium-99M radioaerosol (MMAD = 3.4 microns) on 2 study days each. Changes in symptoms and forced ventilatory function were also assessed. Clearance was quantified from computer-assisted analyses of gamma camera images of the lower respiratory tract in terms of %removal/min of the radiolabel from the trachea 25 min after inhalation and from the outer zone of the right lung after 1.9 to 3 h. Symptoms, forced ventilatory function, and MCh response were unaffected by either fog. Tracheal clearance was more rapid in four of four subjects after AF (0.83 +/- 1.58% removal/min) compared with that after SF (-0.54 +/- 0.85% removal/min). Outer zone clearance was more rapid in six of seven subjects after AF (0.22 +/- 0.15% removal/min) compared with that after SF (0.01 +/- 0.09% removal/min).

  20. Acute effects of exposure to 56Fe and 16O particles on learning and memory

    USDA-ARS?s Scientific Manuscript database

    Although it has been shown that exposure to HZE particles disrupts cognitive performance when tested 2-4 weeks after irradiation, it has not been determined whether exposure to HZE particles can exert acute effects on cognitive performance; i.e., effects within 4-48 hrs after exposure. The present ...

  1. Exhaled nitric oxide concentration upon acute exposure to moderate altitude.

    PubMed

    Caspersen, C; Stang, J; Thorsen, E; Stensrud, T

    2013-03-01

    The purpose of this study was to assess immediate changes in the partial pressure of nitric oxide (NO) in exhaled gas (PE NO ) in healthy trained subjects who were acutely exposed to moderate altitude. One group of nine and another group of 20 healthy subjects were exposed to an ambient pressure of 728 hPa (546 mmHg) corresponding to an altitude of 2800 m for 5 and 90 min, respectively, in an altitude chamber. PE NO was measured offline by sampling exhaled gas in tight metal foil bags at 5, 30, 60, and 90 min. A correction for increased expiratory flow rate due to gas density effects at altitude was performed (PE NO corr). PE NO was significantly decreased by 13-16%, while the fraction of NO in exhaled gas (FE NO) was increased by 16-19% compared to sea level. There was no significant change in PE NO corr after exposure to altitude for 5, 30, 60, and 90 min. We conclude that there was no change in PENO upon arrival at altitude after correcting for gas density effects on expiratory flow rate. Corrections for altitude effects must be done before comparing measurements performed at different altitudes when using measurements of FENO to monitor athletes who have asthma during training at altitude.

  2. Gene expression-based dosimetry by dose and time in mice following acute radiation exposure.

    PubMed

    Tucker, James D; Divine, George W; Grever, William E; Thomas, Robert A; Joiner, Michael C; Smolinski, Joseph M; Auner, Gregory W

    2013-01-01

    Rapid and reliable methods for performing biological dosimetry are of paramount importance in the event of a large-scale nuclear event. Traditional dosimetry approaches lack the requisite rapid assessment capability, ease of use, portability and low cost, which are factors needed for triaging a large number of victims. Here we describe the results of experiments in which mice were acutely exposed to (60)Co gamma rays at doses of 0 (control) to 10 Gy. Blood was obtained from irradiated mice 0.5, 1, 2, 3, 5, and 7 days after exposure. mRNA expression levels of 106 selected genes were obtained by reverse-transcription real time PCR. Stepwise regression of dose received against individual gene transcript expression levels provided optimal dosimetry at each time point. The results indicate that only 4-7 different gene transcripts are needed to explain ≥ 0.69 of the variance (R(2)), and that receiver-operator characteristics, a measure of sensitivity and specificity, of ≥ 0.93 for these statistical models were achieved at each time point. These models provide an excellent description of the relationship between the actual and predicted doses up to 6 Gy. At doses of 8 and 10 Gy there appears to be saturation of the radiation-response signals with a corresponding diminution of accuracy. These results suggest that similar analyses in humans may be advantageous for use in a field-portable device designed to assess exposures in mass casualty situations.

  3. Gene Expression-Based Dosimetry by Dose and Time in Mice Following Acute Radiation Exposure

    PubMed Central

    Tucker, James D.; Divine, George W.; Grever, William E.; Thomas, Robert A.; Joiner, Michael C.; Smolinski, Joseph M.; Auner, Gregory W.

    2013-01-01

    Rapid and reliable methods for performing biological dosimetry are of paramount importance in the event of a large-scale nuclear event. Traditional dosimetry approaches lack the requisite rapid assessment capability, ease of use, portability and low cost, which are factors needed for triaging a large number of victims. Here we describe the results of experiments in which mice were acutely exposed to 60Co gamma rays at doses of 0 (control) to 10 Gy. Blood was obtained from irradiated mice 0.5, 1, 2, 3, 5, and 7 days after exposure. mRNA expression levels of 106 selected genes were obtained by reverse-transcription real time PCR. Stepwise regression of dose received against individual gene transcript expression levels provided optimal dosimetry at each time point. The results indicate that only 4–7 different gene transcripts are needed to explain ≥ 0.69 of the variance (R2), and that receiver-operator characteristics, a measure of sensitivity and specificity, of ≥ 0.93 for these statistical models were achieved at each time point. These models provide an excellent description of the relationship between the actual and predicted doses up to 6 Gy. At doses of 8 and 10 Gy there appears to be saturation of the radiation-response signals with a corresponding diminution of accuracy. These results suggest that similar analyses in humans may be advantageous for use in a field-portable device designed to assess exposures in mass casualty situations. PMID:24358280

  4. Occupational exposure to electromagnetic fields and acute leukaemia: analysis of a case-control study

    PubMed Central

    Willett, E; McKinney, P; Fear, N; Cartwright, R; Roman, E

    2003-01-01

    Aims: To investigate whether the risk of acute leukaemia among adults is associated with occupational exposure to electromagnetic fields. Methods: Probable occupational exposure to electromagnetic fields at higher than typical residential levels was investigated among 764 patients diagnosed with acute leukaemia during 1991–96 and 1510 sex and age matched controls. A job exposure matrix was applied to the self reported employment histories to determine whether or not a subject was exposed to electromagnetic fields. Risks were assessed using conditional logistic regression for a matched analysis. Results: Study subjects considered probably ever exposed to electromagnetic fields at work were not at increased risk of acute leukaemia compared to those considered never exposed. Generally, no associations were observed on stratification by sex, leukaemia subtype, number of years since exposure stopped, or occupation; there was no evidence of a dose-response effect using increasing number of years exposed. However, relative to women considered never exposed, a significant excess of acute lymphoblastic leukaemia was observed among women probably exposed to electromagnetic fields at work that remained increased irrespective of time prior to diagnosis or job ever held. Conclusion: This large population based case-control study found little evidence to support an association between occupational exposure to electromagnetic fields and acute leukaemia. While an excess of acute lymphoblastic leukaemia among women was observed, it is unlikely that occupational exposure to electromagnetic fields was responsible, given that increased risks remained during periods when exposure above background levels was improbable. PMID:12883018

  5. Chronic vs. Short-Term Acute O 3 Exposure Effects on Nocturnal Transpiration in Two Californian Oaks

    Treesearch

    Nancy Grulke; E. Paoletti; R. L. Heath

    2007-01-01

    We tested the effect of daytime chronic moderate ozone (O3) exposure, short-term acute exposure, and both chronic and acute O3 exposure combined on nocturnal transpiration in California black oak and blue oak seedlings. Chronic O3 exposure (70 ppb for 8 h/day) was implemented in open-top chambers for...

  6. Nuclear Emulsion Measurements of the Astronauts’ Radiation Exposures on Skylab Missions 2, 3 and 4,

    DTIC Science & Technology

    1975-12-10

    AD-AO19 804 NUCLEAR EMULSION MEASUREMENTS OF THE ASTRONAUTS’ RADIATION EXPOSURES ON SKYLAB MISSIONS 2, 3 AND 4 Hermann J. Schaefer, et al Naval...N/A NUCLEAR EMULSION MEASUREMENTS OF THE ASTRONAUTS’ RADIATION EXPOSURES ON SKYLAB MISSIONS 2, 3, AND 4. N/ ___ _ _ ANZ Hermann J. Schaefer and...corresponding shield distribution of the entire vehicle tesi alirections ofetionable whether the very large effort involved in this eask isd• ~~really

  7. Leukemia risk associated with chronic external exposure to ionizing radiation in a French cohort of nuclear workers.

    PubMed

    Metz-Flamant, C; Samson, E; Caër-Lorho, S; Acker, A; Laurier, D

    2012-11-01

    Leukemia is one of the earliest cancer effects observed after acute exposure to relatively high doses of ionizing radiation. Leukemia mortality after external exposure at low doses and low-dose rates has been investigated at the French Atomic Energy Commission (CEA) and Nuclear Fuel Company (AREVA NC) after an additional follow-up of 10 years. The cohort included radiation-monitored workers employed for at least one year during 1950-1994 at CEA or AREVA NC and followed during 1968-2004. Association between external exposure and leukemia mortality was estimated with excess relative risk (ERR) models and time-dependent modifying factors were investigated with time windows. The cohort included 36,769 workers, followed for an average of 28 years, among whom 73 leukemia deaths occurred. Among the workers with a positive recorded dose, the mean cumulative external dose was 21.7 mSv. Results under a 2-year lag assumption suggested that the risk of leukemia (except chronic lymphatic leukemia) increased significantly by 8% per 10 mSv. The magnitude of the association for myeloid leukemia was larger. The higher ERR/Sv for doses received 2-14 years earlier suggest that time since exposure modifies the effect. The ERR/Sv also appeared higher for doses received at exposure rates ≥20 mSv per year. These results are consistent with those found in other studies of nuclear workers. However, confidence intervals are still wide. Further analyses should be conducted in pooled cohorts of nuclear workers.

  8. ESTIMATED RATE OF FATAL AUTOMOBILE ACCIDENTS ATTRIBUTABLE TO ACUTE SOLVENT EXPOSURE AT LOW INHALED CONCENTRATIONS

    EPA Science Inventory

    Acute solvent exposures may contribute to automobile accidents because they increase reaction time and decrease attention, in addition to impairing other behaviors. These effects resemble those of ethanol consumption, both with respect to behavioral effects and neurological mecha...

  9. ESTIMATED RATE OF FATAL AUTOMOBILE ACCIDENTS ATTRIBUTABLE TO ACUTE SOLVENT EXPOSURE AT LOW INHALED CONCENTRATIONS

    EPA Science Inventory

    Acute solvent exposures may contribute to automobile accidents because they increase reaction time and decrease attention, in addition to impairing other behaviors. These effects resemble those of ethanol consumption, both with respect to behavioral effects and neurological mecha...

  10. Comparison of Acute Health Effects From Exposures to Diesel and Biodiesel Fuel Emissions

    PubMed Central

    Mehus, Aaron A.; Reed, Rustin J.; Lee, Vivien S. T.; Littau, Sally R.; Hu, Chengcheng; Lutz, Eric A.

    2015-01-01

    Objective: To investigate the comparative acute health effects associated with exposures to diesel and 75% biodiesel/25% diesel (B75) blend fuel emissions. Methods: We analyzed multiple health endpoints in 48 healthy adults before and after exposures to diesel and B75 emissions in an underground mine setting—lung function, lung and systemic inflammation, novel biomarkers of exposure, and oxidative stress were assessed. Results: B75 reduced respirable diesel particulate matter by 20%. Lung function declined significantly more after exposure to diesel emissions. Lung inflammatory cells along with sputum and plasma inflammatory mediators increased significantly to similar levels with both exposures. Urinary 8-hydroxydeoxyguanosine, a marker of oxidative stress, was not significantly changed after either exposure. Conclusions: Use of B75 lowered respirable diesel particulate matter exposure and some associated acute health effects, although lung and systemic inflammation were not reduced compared with diesel use. PMID:26147538

  11. Comparison of Acute Health Effects From Exposures to Diesel and Biodiesel Fuel Emissions.

    PubMed

    Mehus, Aaron A; Reed, Rustin J; Lee, Vivien S T; Littau, Sally R; Hu, Chengcheng; Lutz, Eric A; Burgess, Jefferey L

    2015-07-01

    To investigate the comparative acute health effects associated with exposures to diesel and 75% biodiesel/25% diesel (B75) blend fuel emissions. We analyzed multiple health endpoints in 48 healthy adults before and after exposures to diesel and B75 emissions in an underground mine setting-lung function, lung and systemic inflammation, novel biomarkers of exposure, and oxidative stress were assessed. B75 reduced respirable diesel particulate matter by 20%. Lung function declined significantly more after exposure to diesel emissions. Lung inflammatory cells along with sputum and plasma inflammatory mediators increased significantly to similar levels with both exposures. Urinary 8-hydroxydeoxyguanosine, a marker of oxidative stress, was not significantly changed after either exposure. Use of B75 lowered respirable diesel particulate matter exposure and some associated acute health effects, although lung and systemic inflammation were not reduced compared with diesel use.

  12. Mechanism underlying acute lung injury due to sulfur mustard exposure in rats.

    PubMed

    Xiaoji, Zhu; Xiao, Meng; Rui, Xu; Haibo, Chu; Chao, Zhao; Chengjin, Lian; Tao, Wang; Wenjun, Guo; Shengming, Zhang

    2016-08-01

    Sulfur mustard (SM), a bifunctional alkylating agent that causes severe lung damage, is a significant threat to both military and civilian populations. The mechanisms mediating the cytotoxic effects of SM are unknown and were investigated in this study. The purpose of this study was to establish a rat model of SM-induced lung injury to observe the resulting changes in the lungs. Male rats (Sprague Dawley) were anesthetized, intratracheally intubated, and exposed to 2 mg/kg of SM by intratracheal instillation. Animals were euthanized 6, 24, 48, and 72 h post-exposure, and bronchoalveolar lavage fluid (BALF) and lung tissues were collected. Exposure of rats to SM resulted in rapid pulmonary toxicity, including partial bronchiolar epithelium cell shedding, focal ulceration, and an increased amount of inflammatory exudate and number of cells in the alveoli. There was also evidence that the protein content and cell count of BALF peaked at 48 h, and the alveolar septum was widened and filled with lymphocytes. SM exposure also resulted in partial loss of type I alveolar epithelial cell membranes, fuzzy mitochondrial cristae, detachment and dissociation of ribosomes attached to the surface of rough endoplasmic reticulum, cracked, missing, and disorganized microvilli of type II alveolar epithelial cells, and increased apoptotic cells in the alveolar septum. The propylene glycol control group, however, was the same as the normal group. These data demonstrate that the mechanism of a high concentration of SM (2 mg/kg) induced acute lung injury include histologic changes, inflammatory reactions, apoptosis, oxidative stress, and nuclear DNA damage; the degree of injury is time dependent. © The Author(s) 2014.

  13. Occupational radiation exposure at nuclear power plants in Japan and the United States

    SciTech Connect

    Imahori, A.

    1983-01-01

    The annual statistical summaries of occupational exposures at nuclear power plants in Japan and the United States are compiled by reactor type for the years 1970 to 1980. The trends of occupational exposures at nuclear power plants in both countries are similar in many respects. Individual doses have been well controlled below the occupational dose limit (0.05 Sv/yr), but the collective doses (man-sieverts) have been increasing with plant age, especially in boiling-water reactors. Most of the occupational exposure at nuclear power plants is incurred during maintenance activities rather than routine operation; so the annual collective dose per unit of electric output is in inverse proportion to the annual plant capacity factor. An estimate of the cancer risk for the total number of workers exposed at commercial nuclear power plants in 1980 is fewer than ten hypothetical radiation-induced cancer deaths in the United States and fewer than three in Japan.

  14. Sources and magnitude of occupational and public exposures from nuclear medicine procedures

    SciTech Connect

    1996-03-11

    This Report addresses the sources of exposures incurred in the practice of nuclear medicine and provides the necessary data to evaluate the magnitude of exposures to those directly associated with that practice and to those who provide nursing care to the patients containing radiopharmaceuticals. Exposure to members of the public are also addressed. The primary emphasis of this Report is on these individuals and not on the patient, since the patient receives the direct benefit from the nuclear medicine procedure. It is recognized that the patient also receives the bulk of any potential radiation decrement.

  15. Response of rat alveolar macrophages to ozone: quantitative assessment of population size, morphology, and proliferation following acute exposure

    SciTech Connect

    Hotchkiss, J.A.; Harkema, J.R.; Kirkpatrick, D.T.; Henderson, R.F.

    1989-01-01

    The purpose of this study was to evaluate the in vivo effects of an acute exposure to low levels of ozone on rat pulmonary alveolar macrophages (PAM). Fisher 344 rats exposed to 0.0, 0.12, 0.8, or 1.5 ppm O3 for 6 h were killed immediately after and 3, 18, 42, or 66 h after ozone exposure and their lungs were lavaged. Compared to sham-exposed (control) rats, exposure to 0.12 ppm O3 had no measurable effect on the total number, labeling index (LI), mitotic index (MI), or morphology of rat alveolar macrophages. The number of neutrophils was significantly (p less than or equal to 0.001) greater than in controls at 3, 18, and 42 h after exposure to 1.5 ppm O3 and 42 h after exposure to 0.8 ppm O3. The number of PAM was approximately twice that of controls 42 and 66 h after exposure to 0.8 and 1.5 ppm O3. There was a significant (p less than or equal to 0.001) increase in PAM MI 42 and 66 h after exposure to 1.5 ppm O3 and 42 h after 0.8 ppm O3. The increase in the number of PAM in mitosis was preceded by an increase in PAM LI. The PAM LI was significantly (p less than or equal to 0.001) greater than controls 18 and 42 h after exposure but returned to near normal levels by 66 h after exposure. There was a transient decrease in the mean nuclear/cytoplasmic ratio of PAM from rats exposed to 1.5 ppm O3 18 and 42 h after exposure due to an increase in the mean PAM cytoplasmic area. Comparison of the PAM population doubling time (Dt) and cell cycle time (Ct) suggest that PAM proliferation played a significant role in the observed increase in PAM following exposure to 0.8 and 1.5 ppm O3. These results highlight the dynamic response of PAM to an acute exposure to ozone and suggest that the proliferative response of pulmonary alveolar macrophages may be a useful indicator of pulmonary damage following inhalation of an irritant oxidant.

  16. Brewing complications: the effect of acute ethanol exposure on wound healing

    PubMed Central

    Radek, Katherine A.; Ranzer, Matthew J.; DiPietro, Luisa A.

    2009-01-01

    Ethanol consumption is linked to a higher incidence of traumatic wounds and increases the risk for morbidity and mortality following surgical or traumatic injury. One of the most profound effects of acute ethanol exposure on wound healing occurs during the inflammatory response, and altered cytokine production is a primary component. Acute ethanol exposure also impairs the proliferative response during healing, causing delays in epithelial coverage, collagen synthesis, and blood vessel regrowth. The accumulated data support the paradigm that acute ethanol intoxication prior to injury significantly diminishes a patient’s ability to heal efficiently. PMID:19675208

  17. AGE-RELATED TOXICITY PATHWAY ANALYSIS IN BROWN NORWAY RAT BRAIN FOLLOWING ACUTE TOLUENE EXPOSURE

    EPA Science Inventory

    The influence of aging on susceptibility to environmental exposures is poorly understood. To investigate-the contribution of different life stages on response to toxicants, we examined the effects of an acute exposure to the volatile organic compound, toluene (0.0 or 1.0 g/kg), i...

  18. ASSESSING THE IMPORTANCE OF THE BEHAVIORAL EFFECT OF ACUTE EXPOSURE TO TOLUENE IN HUMANS.

    EPA Science Inventory

    There is increasing interest in being able to evaluate potential benefit-cost relationships of controlling exposure to toxic substances. Behavioral effects of acute toluene exposure could be subjected to benefit-cost analysis if it's effects were quantitatively compared to tho...

  19. ACUTE EXPOSURE TO MOLINATE ALTERS NEUROENDOCRINE CONTROL OF OVULATION IN THE RAT

    EPA Science Inventory

    Molinate, a thiocarbamate herbicide, has been shown previously to impair reproductive capability in the male rat. In a two-generation study, molinate exposure to female rats resulted in altered pregnancy outcome. However, published data is lacking on the effects of acute exposure...

  20. USE OF LETHALITY DATA DURING CATEGORICAL REGRESSION MODELING OF ACUTE REFERENCE EXPOSURES

    EPA Science Inventory

    Categorical regression is being considered by the U.S. EPA as an additional tool for derivation of acute reference exposures (AREs) to be used for human health risk assessment for exposure to inhaled chemicals. Categorical regression is used to calculate probability-response fun...

  1. AGE-RELATED TOXICITY PATHWAY ANALYSIS IN BROWN NORWAY RAT BRAIN FOLLOWING ACUTE TOLUENE EXPOSURE

    EPA Science Inventory

    The influence of aging on susceptibility to environmental exposures is poorly understood. To investigate-the contribution of different life stages on response to toxicants, we examined the effects of an acute exposure to the volatile organic compound, toluene (0.0 or 1.0 g/kg), i...

  2. ACUTE EXPOSURE TO MOLINATE ALTERS NEUROENDOCRINE CONTROL OF OVULATION IN THE RAT

    EPA Science Inventory

    Molinate, a thiocarbamate herbicide, has been shown previously to impair reproductive capability in the male rat. In a two-generation study, molinate exposure to female rats resulted in altered pregnancy outcome. However, published data is lacking on the effects of acute exposure...

  3. ASSESSING THE IMPORTANCE OF THE BEHAVIORAL EFFECT OF ACUTE EXPOSURE TO TOLUENE IN HUMANS.

    EPA Science Inventory

    There is increasing interest in being able to evaluate potential benefit-cost relationships of controlling exposure to toxic substances. Behavioral effects of acute toluene exposure could be subjected to benefit-cost analysis if it's effects were quantitatively compared to tho...

  4. Effects of acute electromagnetic fields exposure on the interhemispheric homotopic functional connectivity during resting state.

    PubMed

    Lv, Bin; Shao, Qing; Chen, Zhiye; Ma, Lin; Wu, Tongning

    2015-08-01

    In this paper, we aimed to investigate the possible effects of acute radiofrequency electromagnetic fields (EMF) on the interhemispheric homotopic functional connectivity with resting state functional magnetic resonance imaging (fMRI) technique. We designed a controllable LTE-related EMF exposure environment at 2.573 GHz and performed the 30 min real/sham exposure experiments on human brain under the safety limits. The resting state fMRI signals were collected before and after EMF exposure. Then voxel-mirrored homotopic connectivity method was utilized to evaluate the acute effects of LTE EMF exposure on the homotopic functional connectivity between two human hemispheres. Based on our previous research, we further demonstrated that the 30 min short-term LTE EMF exposure would modulate the interhemispheric homotopic functional connectivity in resting state around the medial frontal gyrus and the paracentral lobule during the real exposure.

  5. Acute Exposure Guideline Levels (AEGLs) for Time Varying Toxic Plumes

    DTIC Science & Technology

    2014-09-12

    chemicals for a general population. Inhalation exposures in the real world, however, vary strongly in space and time and thus do not correspond to the...12-09-2014 Memorandum Report Toxic airborne contaminants Health effects prediction Space and time varying exposures Extension of EPA AEGLs 64-4464...few fixed-duration exposures to a few constant-density conditions are tabulated. The issue of how to treat real toxic plumes, whose agent density

  6. Occupational exposures of nuclear power plant workers in Finland.

    PubMed

    Alm-Lytz, K; Riihiluoma, V; Hyvönen, H

    2001-01-01

    In Finland, the Radiation and Nuclear Safety Authority (STUK) maintains a central dose register where all occupational doses of radiation workers are recorded. The computerised register enables easy control of personal doses, including annual, 5 year and lifetime doses. The type of radiation work is also recorded in the dose register. Finland was one of the first countries in the world to introduce dose limits based on the recommendations of ICRP 60. In this article, the radiation dose data of the Finnish nuclear power plant workers are analysed. The majority of the radiation doses are received during the maintenance outages. The trend of the 5 year doses and their distribution are presented. Doses received during different work assignments were averaged over the years 1996-1999 and they are also discussed in this article.

  7. Guidelines for exposure assessment in health risk studies following a nuclear reactor accident.

    PubMed

    Bouville, André; Linet, Martha S; Hatch, Maureen; Mabuchi, Kiyohiko; Simon, Steven L

    2014-01-01

    Worldwide concerns regarding health effects after the Chernobyl and Fukushima nuclear power plant accidents indicate a clear need to identify short- and long-term health impacts that might result from accidents in the future. Fundamental to addressing this problem are reliable and accurate radiation dose estimates for the affected populations. The available guidance for activities following nuclear accidents is limited with regard to strategies for dose assessment in health risk studies. Here we propose a comprehensive systematic approach to estimating radiation doses for the evaluation of health risks resulting from a nuclear power plant accident, reflected in a set of seven guidelines. Four major nuclear reactor accidents have occurred during the history of nuclear power production. The circumstances leading to these accidents were varied, as were the magnitude of the releases of radioactive materials, the pathways by which persons were exposed, the data collected afterward, and the lifestyle factors and dietary consumption that played an important role in the associated radiation exposure of the affected populations. Accidents involving nuclear reactors may occur in the future under a variety of conditions. The guidelines we recommend here are intended to facilitate obtaining reliable dose estimations for a range of different exposure conditions. We recognize that full implementation of the proposed approach may not always be feasible because of other priorities during the nuclear accident emergency and because of limited resources in manpower and equipment. The proposed approach can serve as a basis to optimize the value of radiation dose reconstruction following a nuclear reactor accident.

  8. [Effect of acute exposure to high altitude on pharmacokinetics of propranolol and metoprolol in rats].

    PubMed

    Zhang, Juanhong; Wang, Rong; Xie, Hua; Yin, Qiang; Jia, Zhengping; Li, Wenbin

    2014-11-01

    To study the pharmacokinetics of propranolol and metoprolol in rats after acute exposure to high altitude. Wistar rats were randomly assigned into 4 groups for treatment with intragastric administration of propranolol or metoprolol after acute exposure to high altitude (4010 m) or normal altitude (50 m). Venous blood samples were collected from the rats at different time points after drug administration to determine the drug concentrations in the plasma and plasma ultrafiltrate using liquid chromatography-mass spectrometry (LC-MS/MS). The protein binding rate of propranolol was significantly increased but that of metoprolol remained unchanged after acute exposure to high altitude. Compared with the rats exposed to normal altitude, the rats with acute exposure to high altitude showed significant alterations in the pharmacokinetic parameters of the drugs, shown by increased Cmax and AUC, prolonged t1/2 and MRT, and lowered Clz/F of propranolol, and by increased Tmax and prolonged t1/2 and MRT of metoprolol without obvious changes of the parameters of the compartmental model. Significant changes in the pharmacokinetics of propranolol and metoprolol occur in rats after acute exposure to high altitude possibly in relation to, apart from the changes in plasma protein binding ratio and blood gas, alterations in metabolic enzyme activities, increased blood viscosity, and species and general conditions of the animals.

  9. Effects of acute exposure to nitrogen dioxide on primary antibody response

    SciTech Connect

    Hidekazu, F.; Fujio, S.

    1981-01-01

    The effects of acute exposure to nitrogen dioxide on primary humoral antibody response to sheep red blood cells in mice were studied. Mice were exposed to 5 ppm, 20 ppm, and 40 ppm nitrogen dioxide for 12 hr. An exposure of 20 ppm or 40 ppm resulted in a significant suppression of antibody responses, but 5 ppm did not affect antibody response. This immunosuppression resulting from nitrogen dioxide exposure was more apparent in males than females. Exposures to 20 ppm nitrogen dioxide for various time intervals revealed that the strongest suppression effect was observed in the group exposed 2 days after antigen injection. A decreased total cell number in the spleen, and more strikingly, in the thymus, was also caused by acute exposure to nitrogen dioxide.

  10. Effects of acute exposure to nitrogen dioxide on primary antibody response

    SciTech Connect

    Hidekazu, F.; Fujio, S.

    1981-05-01

    The effects of acute exposure to nitrogen dioxide on primary humoral antibody response to sheep red blood cells in mice were studied. Mice were exposed to 5 ppM, 20 ppM, and 40 ppM nitrogen dioxide for 12 h. An exposure of 20 ppM or 40 ppM resulted in a significant suppression of antibody responses, but 5 ppM did not affect antibody response. This immunosuppression resulting from nitrogen dioxide exposure was more apparent in males than females. Exposures to 20 ppM nitrogen dioxide for various time intervals revealed that the strongest suppression effect was observed in the group exposed 2 days after antigen injection. A decreased total cell number in the spleen, and more strikingly, in the thymus, was also caused by acute exposure to nitrogen dioxide.

  11. Temporal trends in childhood leukaemia incidence following exposure to radioactive fallout from atmospheric nuclear weapons testing.

    PubMed

    Wakeford, Richard; Darby, Sarah C; Murphy, Michael F G

    2010-05-01

    Notably raised rates of childhood leukaemia incidence have been found near some nuclear installations, in particular Sellafield and Dounreay in the United Kingdom, but risk assessments have concluded that the radiation doses estimated to have been received by children or in utero as a result of operations at these installations are much too small to account for the reported increases in incidence. This has led to speculation that the risk of childhood leukaemia arising from internal exposure to radiation following the intake of radioactive material released from nuclear facilities has been substantially underestimated. The radionuclides discharged from many nuclear installations are similar to those released into the global environment by atmospheric nuclear weapons testing, which was at its height in the late-1950s and early-1960s. Measurements of anthropogenic radionuclides in members of the general public resident in the vicinity of Sellafield and Dounreay have found levels that do not differ greatly from those in persons living remote from nuclear installations that are due to ubiquitous exposure to the radioactive debris of nuclear weapons testing. Therefore, if the leukaemia risk to children resulting from deposition within the body of radioactive material discharged from nuclear facilities has been grossly underestimated, then a pronounced excess of childhood leukaemia would have been expected as a consequence of the short period of intense atmospheric weapons testing. We have examined childhood leukaemia incidence in 11 large-scale cancer registries in three continents for which data were available at least as early as 1962. We found no evidence of a wave of excess cases corresponding to the peak of radioactive fallout from atmospheric weapons testing. The absence of a discernible increase in the incidence of childhood leukaemia following the period of maximum exposure to the radioactive debris of this testing weighs heavily against the suggestion that

  12. Acute Neuroactive Drug Exposures alter Locomotor Activity in Larval Zebrafish

    EPA Science Inventory

    As part of the development of a rapid in vivo screen for prioritization of toxic chemicals, we have begun to characterize the locomotor activity of zebrafish (Danio rerio) larvae by assessing the acute effects of prototypic drugs that act on the central nervous system. Initially,...

  13. Acute Neuroactive Drug Exposures alter Locomotor Activity in Larval Zebrafish

    EPA Science Inventory

    As part of the development of a rapid in vivo screen for prioritization of toxic chemicals, we have begun to characterize the locomotor activity of zebrafish (Danio rerio) larvae by assessing the acute effects of prototypic drugs that act on the central nervous system. Initially,...

  14. A Novel Antibody-Based Biomarker for Chronic Algal Toxin Exposure and Sub-Acute Neurotoxicity

    PubMed Central

    Lefebvre, Kathi A.; Frame, Elizabeth R.; Gulland, Frances; Hansen, John D.; Kendrick, Preston S.; Beyer, Richard P.; Bammler, Theo K.; Farin, Frederico M.; Hiolski, Emma M.; Smith, Donald R.; Marcinek, David J.

    2012-01-01

    The neurotoxic amino acid, domoic acid (DA), is naturally produced by marine phytoplankton and presents a significant threat to the health of marine mammals, seabirds and humans via transfer of the toxin through the foodweb. In humans, acute exposure causes a neurotoxic illness known as amnesic shellfish poisoning characterized by seizures, memory loss, coma and death. Regular monitoring for high DA levels in edible shellfish tissues has been effective in protecting human consumers from acute DA exposure. However, chronic low-level DA exposure remains a concern, particularly in coastal and tribal communities that subsistence harvest shellfish known to contain low levels of the toxin. Domoic acid exposure via consumption of planktivorous fish also has a profound health impact on California sea lions (Zalophus californianus) affecting hundreds of animals yearly. Due to increasing algal toxin exposure threats globally, there is a critical need for reliable diagnostic tests for assessing chronic DA exposure in humans and wildlife. Here we report the discovery of a novel DA-specific antibody response that is a signature of chronic low-level exposure identified initially in a zebrafish exposure model and confirmed in naturally exposed wild sea lions. Additionally, we found that chronic exposure in zebrafish caused increased neurologic sensitivity to DA, revealing that repetitive exposure to DA well below the threshold for acute behavioral toxicity has underlying neurotoxic consequences. The discovery that chronic exposure to low levels of a small, water-soluble single amino acid triggers a detectable antibody response is surprising and has profound implications for the development of diagnostic tests for exposure to other pervasive environmental toxins. PMID:22567140

  15. A novel antibody-based biomarker for chronic algal toxin exposure and sub-acute neurotoxicity

    USGS Publications Warehouse

    Lefebvre, Kathi A.; Frame, Elizabeth R.; Gulland, Frances; Hansen, John D.; Kendrick, Preston S.; Beyer, Richard P.; Bammler, Theo K.; Farin, Frederico M.; Hiolski, Emma M.; Smith, Donald R.; Marcinek, David J.

    2012-01-01

    The neurotoxic amino acid, domoic acid (DA), is naturally produced by marine phytoplankton and presents a significant threat to the health of marine mammals, seabirds and humans via transfer of the toxin through the foodweb. In humans, acute exposure causes a neurotoxic illness known as amnesic shellfish poisoning characterized by seizures, memory loss, coma and death. Regular monitoring for high DA levels in edible shellfish tissues has been effective in protecting human consumers from acute DA exposure. However, chronic low-level DA exposure remains a concern, particularly in coastal and tribal communities that subsistence harvest shellfish known to contain low levels of the toxin. Domoic acid exposure via consumption of planktivorous fish also has a profound health impact on California sea lions (Zalophus californianus) affecting hundreds of animals yearly. Due to increasing algal toxin exposure threats globally, there is a critical need for reliable diagnostic tests for assessing chronic DA exposure in humans and wildlife. Here we report the discovery of a novel DA-specific antibody response that is a signature of chronic low-level exposure identified initially in a zebrafish exposure model and confirmed in naturally exposed wild sea lions. Additionally, we found that chronic exposure in zebrafish caused increased neurologic sensitivity to DA, revealing that repetitive exposure to DA well below the threshold for acute behavioral toxicity has underlying neurotoxic consequences. The discovery that chronic exposure to low levels of a small, water-soluble single amino acid triggers a detectable antibody response is surprising and has profound implications for the development of diagnostic tests for exposure to other pervasive environmental toxins.

  16. Guidelines for Exposure Assessment in Health Risk Studies Following a Nuclear Reactor Accident

    PubMed Central

    Bouville, André; Linet, Martha S.; Hatch, Maureen; Mabuchi, Kiyohiko

    2013-01-01

    Background: Worldwide concerns regarding health effects after the Chernobyl and Fukushima nuclear power plant accidents indicate a clear need to identify short- and long-term health impacts that might result from accidents in the future. Fundamental to addressing this problem are reliable and accurate radiation dose estimates for the affected populations. The available guidance for activities following nuclear accidents is limited with regard to strategies for dose assessment in health risk studies. Objectives: Here we propose a comprehensive systematic approach to estimating radiation doses for the evaluation of health risks resulting from a nuclear power plant accident, reflected in a set of seven guidelines. Discussion: Four major nuclear reactor accidents have occurred during the history of nuclear power production. The circumstances leading to these accidents were varied, as were the magnitude of the releases of radioactive materials, the pathways by which persons were exposed, the data collected afterward, and the lifestyle factors and dietary consumption that played an important role in the associated radiation exposure of the affected populations. Accidents involving nuclear reactors may occur in the future under a variety of conditions. The guidelines we recommend here are intended to facilitate obtaining reliable dose estimations for a range of different exposure conditions. We recognize that full implementation of the proposed approach may not always be feasible because of other priorities during the nuclear accident emergency and because of limited resources in manpower and equipment. Conclusions: The proposed approach can serve as a basis to optimize the value of radiation dose reconstruction following a nuclear reactor accident. Citation: Bouville A, Linet MS, Hatch M, Mabuchi K, Simon SL. 2014. Guidelines for exposure assessment in health risk studies following a nuclear reactor accident. Environ Health Perspect 122:1–5; http://dx.doi.org/10

  17. Acute low-level microwave exposure and central cholinergic activity: studies on irradiation parameters

    SciTech Connect

    Lai, H.; Horita, A.; Guy, A.W.

    1988-01-01

    Sodium-dependent high-affinity choline uptake was measured in the striatum, frontal cortex, hippocampus, and hypothalamus of rats after acute exposure (45 min) to pulsed (2 microseconds, 500 pps) or continuous-wave 2,450-MHz microwaves in cylindrical waveguides or miniature anechoic chambers. In all exposure conditions, the average whole-body specific absorption rate was at 0.6 W/kg. Decrease in choline uptake was observed in the frontal cortex after microwave exposure in all of the above irradiation conditions. Regardless of the exposure system used, hippocampal choline uptake was decreased after exposure to pulsed but not continuous-wave microwaves. Striatal choline uptake was decreased after exposure to either pulsed or continuous-wave microwaves in the miniature anechoic chamber. No significant change in hypothalamic choline uptake was observed under any of the exposure conditions studied. We conclude that depending on the parameters of the radiation, microwaves can elicit specific and generalized biological effects.

  18. Nuclear accumulation of cyclin D1 following long-term fractionated exposures to low-dose ionizing radiation in normal human diploid cells.

    PubMed

    Shimura, Tsutomu; Hamada, Nobuyuki; Sasatani, Megumi; Kamiya, Kenji; Kunugita, Naoki

    2014-01-01

    Cyclin D1 is a mitogenic sensor that responds to growth signals from the extracellular environment and regulates the G 1-to-S cell cycle transition. When cells are acutely irradiated with a single dose of 10 Gy, cyclin D1 is degraded, causing cell cycle arrest at the G 1/S checkpoint. In contrast, cyclin D1 accumulates in human tumor cells that are exposed to long-term fractionated radiation (0.5 Gy/fraction of X-rays). In this study we investigated the effect of fractionated low-dose radiation exposure on cyclin D1 localization in 3 strains of normal human fibroblasts. To specifically examine the nuclear accumulation of cyclin D1, cells were treated with a hypotonic buffer containing detergent to remove cytoplasmic cyclin D1. Proliferating cell nuclear antigen (PCNA) immunofluorescence was used to identify cells in S phase. With this approach, we observed S-phase nuclear retention of cyclin D1 following low-dose fractionated exposures, and found that cyclin D1 nuclear retention increased with exposure time. Cells that retained nuclear cyclin D1 were more likely to have micronuclei than non-retaining cells, indicating that the accumulation of nuclear cyclin D1 was associated with genomic instability. Moreover, inhibition of the v-akt murine thymoma viral oncogene homolog (AKT) pathway facilitated cyclin D1 degradation and eliminated cyclin D1 nuclear retention in cells exposed to fractionated radiation. Thus, cyclin D1 may represent a useful marker for monitoring long-term effects associated with exposure to low levels of radiation.

  19. Risk of leukaemia mortality from exposure to ionising radiation in US nuclear workers: a pooled case-control study.

    PubMed

    Daniels, Robert D; Bertke, Stephen; Waters, Kathleen M; Schubauer-Berigan, Mary K

    2013-01-01

    To follow-up on earlier studies of the leukaemogenicity of occupational ionising radiation exposure. We conducted a nested case-control analysis of leukaemia mortality in a pooled cohort of US nuclear workers followed through 2005. Each case was matched to four controls on attained age. Exposures were estimated from available records. General relative risk models were used to estimate the excess relative risk (ERR) of leukaemia, excluding chronic lymphocytic (CLL), acute myeloid leukaemia, chronic myeloid leukaemia and CLL while controlling for potential confounders. Preferred exposure lags and time-windows of risks were calculated using joint maximum likelihood. Dose-response was also examined using linear, linear-quadratic, categorical and restricted cubic spline models. There were 369 leukaemia deaths in 105 245 US nuclear workers. The adjusted ERR for non-CLL leukaemia was 0.09 (95% CI -0.17 to 0.65) per 100 mGy. Elevated non-CLL risks were observed from exposures occurring 6-14 years prior to attained age of cases (ERR per 100 mGy=1.9; 95% CI <0 to 8.0). Lagged models indicated non-linearity of risk at very low (<10 mGy) and high (>100 mGy) doses, which contributed to the imprecision of results in linear models. Similar risk attenuation was not evident in time-windows-based models. Risk estimates were in reasonable agreement with previous estimates, with the temporality of non-CLL leukaemia risk as a dominant factor in dose-response analyses. Future research should focus on methods that improve evaluations of the dose-response, particularly in the low-dose range.

  20. Consequences of acute and chronic exposure to arsenic in children.

    PubMed

    Calderon, Rebecca L; Abernathy, Charles O; Thomas, David J

    2004-07-01

    Arsenic is a toxic chemical and may cause adverse health effects in children and adults. It is known to affect the nervous, gastrointestinal, and hematological systems and cause skin and internal cancers in people exposed to levels greater than 300 ppb in their drinking water. For most people, the major exposure to arsenic comes from food (8 to 14 microg inorganic arsenic per day), but when the arsenic level in water is elevated, drinking water becomes the predominant source of exposure. Because it is very difficult to limit arsenic exposure from food, it would be wise to limit arsenic exposure from those more controllable sources. Pediatricians should ascertain the levels of arsenic in drinking water of patients with high arsenic levels, using the supplier or, in the case of private wells, a professional water-testing laboratory assay. The Safe Drinking Water Act does not cover private wells or those water systems with less than 15 hook-ups or those that serve less than 25 people. Pediatricians should instruct parents to use prepared baby formulas or prepare them using water with the arsenic removed and to curtail playing time for younger children in places that have sand containing large amounts of arsenic. Such procedures will limit arsenic exposure to a minimum.

  1. Medical countermeasures for unwanted CBRN exposures: part II radiological and nuclear threats with review of recent countermeasure patents

    PubMed Central

    Singh, Vijay K.; Romaine, Patricia L.P.; Newman, Victoria L.; Seed, Thomas M.

    2016-01-01

    ABSTRACT Introduction: The global threat of a chemical, biological, radiological, or nuclear (CBRN) disaster is an important priority for all government agencies involved in domestic security and public health preparedness. Radiological/nuclear (RN) attacks or accidents have become a larger focus of the United States Food and Drug administration (US FDA) over time because of their increased likeliness. Clinical signs and symptoms of a developing acute radiation syndrome (ARS) are grouped into three sub-syndromes named for the dominant organ system affected, namely the hematopoietic (H-ARS), gastrointestinal (GI-ARS), and neurovascular systems. The availability of safe and effective countermeasures against radiological/nuclear threats currently represents a significant unmet medical need. Areas covered: This article reviews the development of RN threat medical countermeasures and highlights those specific countermeasures that have been recently patented and approved following the FDA Animal Rule. Patents for such agents from 2015 have been presented. Expert opinion: Two granulocyte colony-stimulating factor (G-CSF)-based radiation countermeasures (Neupogen® (Amgen, Thousand Oaks, CA) and Neulasta® (Amgen, Thousand Oaks, CA)) have recently been approved by the FDA for treatment of H-ARS and both these agents are radiomitigators, used after radiation exposure. To date, there are no FDA-approved radioprotectors for ARS. PMID:27610458

  2. Behavioral and neurochemical changes in response to acute stressors: influence of previous chronic exposure to immobilization.

    PubMed

    Pol, O; Campmany, L; Gil, M; Armario, A

    1992-07-01

    The effect of daily (2 h) exposure to immobilization (IMO) for 15 days on the behavioral and neurochemical responses of adult male rats to acute stress caused by 2-h IMO or 2-h tail-shock was studied. The brain areas studied were frontal cortex, hippocampus, hypothalamus, midbrain, and pons plus medulla. Chronic exposure to IMO did not alter noradrenaline (NA), 3-methoxy,4-hydroxyphenyletileneglycol-SO4 (MHPG-SO4), serotonin, or 5-hydroxindoleacetic acid (5-HIAA) concentrations in any brain area as measured approximately 20 h after the last exposure to IMO. Exposure to behavioral tests did not modify neurochemical variables except NA levels in the hypothalamus of nonchronically stressed (control) rats. Both exposure to 2-h IMO or 2-h shock significantly decreased NA levels in hypothalamus and midbrain of nonchronically stressed rats. These decreases in response to the two acute stressors were not observed in chronically stressed rats. However, MHPG-SO4 levels increased to the same extent in control and chronically stressed rats after exposure to the acute stressors. Likewise, increased 5-HIAA concentrations observed in response to acute stressors were similar in control and chronically stressed rats. The inhibition of activity (areas crossed and rearing) in the holeboard caused by acute IMO was less marked in rats previously exposed to the same stressor than in control rats, but the response to shock was similar. In the forced swim test, acute IMO decreased struggling in control rats but tended to increase it in chronically stressed rats. The response to shock followed the same pattern as that to IMO, although it was slight.(ABSTRACT TRUNCATED AT 250 WORDS)

  3. Acute respiratory symptoms and evacuation-related behavior after exposure to chlorine gas leakage.

    PubMed

    Han, Sung-Woo; Choi, Won-Jun; Yi, Min-Kee; Song, Seng-Ho; Lee, Dong-Hoon; Han, Sang-Hwan

    2016-01-01

    A study was performed on the accidental chlorine gas leakage that occurred in a factory of printed circuit boards manufactured without chlorine. Health examination was performed for all 52 workers suspected of exposure to chlorine gas, and their evacuation-related behaviors were observed in addition to analyzing the factors that affected the duration of their acute respiratory symptoms. Behavioral characteristics during the incidence of the accidental chlorine gas leakage, the estimated time of exposure, and the duration of subjective acute respiratory symptoms were investigated. In addition, clinical examination, chest radiography, and dental erosion test were performed. As variables that affected the duration of respiratory symptoms, dose group, body weight, age, sex, smoking, work period, and wearing a protective gear were included and analyzed by using the Cox proportional hazard model. Of 47 workers exposed to chlorine gas, 36 (77 %) developed more than one subjective symptom. The duration of the subjective symptoms according to exposure level significantly differed, with a median of 1 day (range, 0-5 days) in the low-exposure group and 2 days (range, 0-25 days) in the high-exposure group. Among the variables that affected the duration of the acute respiratory symptoms, which were analyzed by using the Cox proportional hazard model, only exposure level was significant (hazard ratio 2.087, 95 % CI = 1.119, 3.890). Regarding the evacuation-related behaviors, 22 workers (47 %) voluntarily evacuated to a safety zone immediately after recognizing the accidental exposure, but 25 workers (43 %) delayed evacuation until the start of mandatory evacuation (min 5, max 25 min). The duration of the subjective acute respiratory symptoms significantly differed between the low- and high-exposure groups. Among the 27 workers in the high-exposure group, 17 misjudged the toxicity after being aware of the gas leakage, which is a relatively high number.

  4. Is There an Association Between Lifetime Cumulative Exposure and Acute Pulmonary Responses to Ozone?

    PubMed Central

    Arjomandi, Mehrdad; Tager, Ira B.; Bastaki, Maria; Chen, Connie; Holland, Nina; Balmes, John R.

    2012-01-01

    Objective To investigate the potential effects of lifetime cumulative ozone (O3) exposure on acute pulmonary responses to O3. Methods Fifteen healthy subjects from a larger cohort of young adults were exposed to 200 ppb O3 for 4 hours followed by bronchoscopy and bronchoalveolar lavage 18 hours later. Lung function, symptom questionnaires, and blood samples were obtained before and after each exposure. Subjects’ lifetime cumulative O3 exposures were estimated from residential histories and air-quality monitoring data. Results Acute exposure to O3 caused decrements in forced expiratory volume in 1 second (FEV1), maximal mid-expiratory flow rate (FEF25–75), and forced expiratory flow rate at 75% of forced vital capacity (FEF75), and an increase in plasma clara cell protein (CC16) level. Changes in CC16 and lower respiratory symptoms, but not in lung function, were positively correlated with lifetime cumulative O3 exposure. Conclusion Higher lifetime cumulative O3 exposure was associated with airway injury and respiratory symptom responses, but not with airway inflammatory or lung function responses, to acute O3 exposure. PMID:18332784

  5. Is there an association between lifetime cumulative exposure and acute pulmonary responses to ozone?

    PubMed

    Arjomandi, Mehrdad; Tager, Ira B; Bastaki, Maria; Chen, Connie; Holland, Nina; Balmes, John R

    2008-03-01

    To investigate the potential effects of lifetime cumulative ozone (O3) exposure on acute pulmonary responses to O3. Fifteen healthy subjects from a larger cohort of young adults were exposed to 200 ppb O3 for 4 hours followed by bronchoscopy and bronchoalveolar lavage 18 hours later. Lung function, symptom questionnaires, and blood samples were obtained before and after each exposure. Subjects' lifetime cumulative O3 exposures were estimated from residential histories and air-quality monitoring data. Acute exposure to O3 caused decrements in forced expiratory volume in 1 second (FEV1), maximal mid-expiratory flow rate (FEF25-75), and forced expiratory flow rate at 75% of forced vital capacity (FEF75), and an increase in plasma clara cell protein (CC16) level. Changes in CC16 and lower respiratory symptoms, but not in lung function, were positively correlated with lifetime cumulative O3 exposure. Higher lifetime cumulative O3 exposure was associated with airway injury and respiratory symptom responses, but not with airway inflammatory or lung function responses, to acute O3 exposure.

  6. Prenatal cortisol exposure predicts infant cortisol response to acute stress.

    PubMed

    O'Connor, Thomas G; Bergman, Kristin; Sarkar, Pampa; Glover, Vivette

    2013-03-01

    Experimental animal findings suggest that early stress and glucocorticoid exposure may program the function of the hypothalamic-pituitary-adrenal (HPA) axis in the offspring. The extension of these findings to human development is not yet clear. A prospective longitudinal study was conducted on 125 mothers and their normally developing children. Amniotic fluid was obtained at, on average, 17.2 weeks gestation; infant behavior and cortisol response to a separation-reunion stress was assessed at 17 months. Amniotic fluid cortisol predicted infant cortisol response to separation-reunion stress: infants who were exposed to higher levels of cortisol in utero showed higher pre-stress cortisol values and blunted response to stress exposure. The association was independent of prenatal, obstetric, and socioeconomic factors and child-parent attachment. The findings provide some of the strongest data in humans that HPA axis functioning in the child may be predicted from prenatal cortisol exposure.

  7. Distinct Profiles of Anxiety and Dysphoria during Spontaneous Withdrawal from Acute Morphine Exposure

    PubMed Central

    Rothwell, Patrick E.; Thomas, Mark J.; Gewirtz, Jonathan C.

    2009-01-01

    The negative motivational aspects of withdrawal include symptoms of both anxiety and depression, and emerge following termination of chronic drug use as well as after acute drug exposure. States of acute withdrawal are an inherent part of intermittent drug use in humans, but the contribution of acute withdrawal to the development of addiction has received limited systematic investigation, due to a lack of preclinical models for withdrawal states that emerge spontaneously after acute drug exposure. Here, we have characterized a spontaneous increase in the magnitude of the acoustic startle reflex (i.e., spontaneous withdrawal-potentiated startle) that emerges following acute morphine administration in rats, and compared the time course of startle potentiation and place conditioning. We find that startle potentiation appears related to a decrease in opiate receptor occupancy and reflects an anxiety-like state with a pharmacological profile similar to other signs of opiate withdrawal. Spontaneous startle potentiation emerges before the rewarding effects of morphine have subsided, even though naloxone administration after a single morphine exposure causes both startle potentiation and conditioned place aversion (CPA). These results demonstrate that negative emotional signs of withdrawal develop following just one exposure to morphine, and are likely a recurrent aspect of intermittent drug use that may contribute to the earliest adaptations underlying the development of addiction. Furthermore, the dissociation between spontaneous startle potentiation and CPA suggests anxiogenic and dysphoric manifestations of opiate withdrawal may be mediated by distinct neural mechanisms that are progressively engaged as withdrawal unfolds. PMID:19494807

  8. Acute exacerbation of idiopathic pulmonary fibrosis associated with air pollution exposure.

    PubMed

    Johannson, Kerri A; Vittinghoff, Eric; Lee, Kiyoung; Balmes, John R; Ji, Wonjun; Kaplan, Gilaad G; Kim, Dong Soon; Collard, Harold R

    2014-04-01

    Acute exacerbations of idiopathic pulmonary fibrosis are associated with high mortality and are of unknown cause. The effect of air pollution on exacerbations of interstitial lung disease is unknown. This study aims to define the association of air pollution exposure with acute exacerbation of idiopathic pulmonary fibrosis. Patients with idiopathic pulmonary fibrosis and corresponding air pollution data were identified from a longitudinal cohort. Air pollution exposures were assigned to each patient for ozone, nitrogen dioxide, particulate matter, sulfur dioxide and carbon monoxide based on geo-coded residential addresses. Cox proportional hazards models were used to estimate the association of air pollution exposures and acute exacerbations. Acute exacerbation was significantly associated with antecedent 6-week increases in mean level, maximum level and number of exceedances above accepted standards of ozone (hazard ratio (HR) 1.57, 95% CI 1.09-2.24; HR 1.42, 95% CI 1.11-1.82; and HR 1.51, 95% CI 1.17-1.94, respectively) and nitrogen dioxide (HR 1.41, 95% CI 1.04-1.91; HR 1.27, 95% CI 1.01-1.59; and HR 1.20, 95% CI 1.10-1.31, respectively). Increased ozone and nitrogen dioxide exposure over the preceding 6 weeks was associated with an increased risk of acute exacerbation of idiopathic pulmonary fibrosis, suggesting that air pollution may contribute to the development of this clinically meaningful event.

  9. Acute and chronic respiratory effects of occupational exposure to ammonia.

    PubMed

    Holness, D L; Purdham, J T; Nethercott, J R

    1989-12-01

    In a soda ash plant, 58 workers exposed to mean airborne ammonia levels of 9.2 +/- 1.4 ppm were compared with 31 control workers with a mean exposure of 0.3 +/- 0.1 ppm. There were no differences between the groups in the reporting of respiratory or cutaneous symptoms, sense of smell, baseline lung function, or change in lung function over a work shift at the beginning and end of a workweek. No relationships between level or length of ammonia exposure and lung function results were demonstrated.

  10. Cumulative exposure to prior collective trauma and acute stress responses to the Boston marathon bombings.

    PubMed

    Garfin, Dana Rose; Holman, E Alison; Silver, Roxane Cohen

    2015-06-01

    The role of repeated exposure to collective trauma in explaining response to subsequent community-wide trauma is poorly understood. We examined the relationship between acute stress response to the 2013 Boston Marathon bombings and prior direct and indirect media-based exposure to three collective traumatic events: the September 11, 2001 (9/11) terrorist attacks, Superstorm Sandy, and the Sandy Hook Elementary School shooting. Representative samples of residents of metropolitan Boston (n = 846) and New York City (n = 941) completed Internet-based surveys shortly after the Boston Marathon bombings. Cumulative direct exposure and indirect exposure to prior community trauma and acute stress symptoms were assessed. Acute stress levels did not differ between Boston and New York metropolitan residents. Cumulative direct and indirect, live-media-based exposure to 9/11, Superstorm Sandy, and the Sandy Hook shooting were positively associated with acute stress responses in the covariate-adjusted model. People who experience multiple community-based traumas may be sensitized to the negative impact of subsequent events, especially in communities previously exposed to similar disasters. © The Author(s) 2015.

  11. Acute Exposure to Particulate Matter (PM) Alters Physiologic ...

    EPA Pesticide Factsheets

    Human exposure to ambient PM from fossil-fuel emissions is linked to cardiovascular disease and death. This association strengthens in people with preexisting cardiopulmonary diseases—especially heart failure (HF). We previously examined the effects of PM on HF by exposing Spontaneously Hypertensive Heart Failure (SHHF) rats to residual oil fly ash (ROFA) after accelerating HF onset via isoproterenol (ISO) infusion. In that study, rats were exposed to PM 2 wks after ISO treatment ceased, which was more than 1 wk after ISO-cessation had induced a 9-d period of hypotension. Epidemiological evidence suggests that effects would be more pronounced if exposure coincided with the HF-like hypotensive period. We hypothesized that PM exposure shortly after cessation of ISO treatment would cause greater cardiopulmonary injury. SHHF rats were infused with ISO (n=24; 1.0 mg/kg/d sc) or saline (n=23) via osmotic pump for 5 wks and then 5 d later exposed by nose-only inhalation for 4 h to either air or 580 µg/m3 of the PM2.5 fraction of a synthetic PM (dried salt solution, MSO4) similar in composition to a well-studied ROFA and consisting of Fe, Ni and V sulfates. In ISO-pretreated rats only, MSO4 decreased pulse pressure (an indirect indicator of cardiac output), decreased systolic and diastolic blood pressures, and increased QA interval (inversely related to myocardial contractility) during inhalation exposure and caused post-inhalation pulmonary inflammation significantl

  12. Toxicogenomic identification of biomarkers of acute respiratory exposure sensitizing agents

    EPA Science Inventory

    Allergy induction requires multiple exposures to an agent. Therefore the development of high-throughput or in vitro assays for effective screening of potential sensitizers will require the identification of biomarkers. The goal of this preliminary study was to identify potential ...

  13. Toxicogenomic identification of biomarkers of acute respiratory exposure sensitizing agents

    EPA Science Inventory

    Allergy induction requires multiple exposures to an agent. Therefore the development of high-throughput or in vitro assays for effective screening of potential sensitizers will require the identification of biomarkers. The goal of this preliminary study was to identify potential ...

  14. Acute neuroactive drug exposures alter locomotor activity in larval zebrafish

    EPA Science Inventory

    In an effort to develop a rapid in vivo screen for EPA's prioritization of toxic chemicals, we are characterizing the locomotor activity of zebrafish (Danio rerio) larvae after exposure to prototypic drugs that act on the central nervous system. MPTP (1-methyl-4phenyl- 1 ,2,3,6-...

  15. Acute neuroactive drug exposures alter locomotor activity in larval zebrafish

    EPA Science Inventory

    In an effort to develop a rapid in vivo screen for EPA's prioritization of toxic chemicals, we are characterizing the locomotor activity of zebrafish (Danio rerio) larvae after exposure to prototypic drugs that act on the central nervous system. MPTP (1-methyl-4phenyl- 1 ,2,3,6-...

  16. Discussion about modeling the effects of neutron flux exposure for nuclear reactor core analysis

    SciTech Connect

    Vondy, D.R.

    1986-04-01

    Methods used to calculate the effects of exposure to a neutron flux are described. The modeling of the nuclear-reactor core history presents an analysis challenge. The nuclide chain equations must be solved, and some of the methods in use for this are described. Techniques for treating reactor-core histories are discussed and evaluated.

  17. Short term hardening effects on survival of acute and chronic cold exposure by Drosophila melanogaster larvae

    PubMed Central

    Rajamohan, Arun; Sinclair, Brent J.

    2008-01-01

    We quantified the variation and plasticity in cold tolerance among four larval stages of four laboratory strains of Drosophila melanogaster in response to both acute (<2 hours of cold exposure) and chronic (∼7 hours of cold exposure) cold exposure. We observed significant differences in basal cold tolerance between the strains and among larval stages. Early larval instars were generally more tolerant of acute cold exposures than 3rd instar larvae. However, wandering larvae were more tolerant of chronic cold exposures than the other stages. Early stages also displayed a more pronounced rapid cold-hardening response than the later stages. Heat pre-treatment did not confer a significant increase in cold tolerance to any of the strains at any stage, pointing to different mechanisms being involved in resolving heat- and cold-elicited damage. However, when heat pre-treatment was combined with rapid cold-hardening as sequential pre-treatments, both positive (heat first) and negative (heat second) effects on cold tolerance were observed. We discuss possible mechanisms underlying cold-hardening and the effects of acute and chronic cold exposures. PMID:18342328

  18. Cardiac Autonomic Effects of Acute Exposures to Airborne Particulates in Men and Women

    NASA Technical Reports Server (NTRS)

    Howarth, M. S.; Schlegel, T. T.; Knapp, C. F.; Patwardhan, A. R.; Jenkins, R. A.; Ilgner, R. H.; Evans, J. M.

    2007-01-01

    The aim of this research was to investigate cardiac autonomic changes associated with acute exposures to airborne particulates. Methods: High fidelity 12-lead ECG (CardioSoft, Houston, TX) was acquired from 19 (10 male / 9 female) non-smoking volunteers (age 33.6 +/- 6.6 yrs) during 10 minutes pre-exposure, exposure and post-exposure to environmental tobacco smoke (ETS), cooking oil fumes, wood smoke and sham (water vapor). To control exposure levels, noise, subject activity, and temperature, all studies were conducted inside an environmental chamber. Results: The short-term fractal scaling exponent (Alpha-1) and the ratio of low frequency to high frequency Heart Rate Variability (HRV) powers (LF/HF, a purported sympathetic index) were both higher in males (p<0.017 and p<0.05, respectively) whereas approximate entropy (ApEn) and HF/(LF+HF) (a purported parasympathetic index) were both lower in males (p<0.036, and p<0.044, respectively). Compared to pre-exposure (p<0.0002) and sham exposure (p<0.047), male heart rates were elevated during early ETS post-exposure. Our data suggest that, in addition to tonic HRV gender differences, cardiac responses to some acute airborne particulates are gender related.

  19. Acute nitrite exposure alters the metabolism of thyroid hormones in grass carp (Ctenopharyngodon idellus).

    PubMed

    Xiao, Chen; Liu, Zidong; Li, Dapeng; Refaey, Mohamed M; Tang, Rong; Li, Li; Zhang, Xi

    2017-08-08

    Nitrite has the potential to disturb thyroid hormone homeostasis, but little is known about the underlying mechanisms. In the present study, juvenile grass carp (Ctenopharyngodon idellus) were exposed to various concentrations of nitrite (0, 0.5, 1, 4, and 16 mg/L, respectively). Serum concentrations of triiodothyronine (T3), thyroxine (T4), free triiodothyronine (FT3), free thyroxine (FT4), 3,3,5'-triiodothyronine (rT3), thyroid-stimulating hormone (TSH), and the activity of iodothyronine deiodinases were assayed at 0, 12, 24, 48, and 96 h after exposure. It was found that acute nitrite exposure significantly altered the TH levels and iodothyronine deiodinase activities. The rT3 levels were significantly increased in the treatment groups, whereas the concentrations of T3, FT3, FT4, and TSH decreased significantly. The concentration of T4 was elevated in the lower-dose exposure group, but was reduced in the higher-dose exposure group. Increases in type I iodothyronine deiodinase (ID1) and type III iodothyronine deiodinase (ID3) activities were observed in the exposure groups. The activity of type II iodothyronine deiodinase (ID2) decreased at 12 and 24 h after exposure. A decrease of colloid in the thyroid follicles was observed in the exposure group. The results indicate that acute nitrite exposure has the potential to disturb the homeostasis of thyroid hormone metabolism, leading to a hypothyroidism state in the juvenile grass carp. Copyright © 2017. Published by Elsevier Ltd.

  20. Chronic and Acute Effects of Coal Tar Pitch Exposure and Cardiopulmonary Mortality Among Aluminum Smelter Workers

    PubMed Central

    Friesen, Melissa C.; Demers, Paul A.; Spinelli, John J.; Eisen, Ellen A.; Lorenzi, Maria F.; Le, Nhu D.

    2010-01-01

    Air pollution causes several adverse cardiovascular and respiratory effects. In occupational studies, where levels of particulate matter and polycyclic aromatic hydrocarbons (PAHs) are higher, the evidence is inconsistent. The effects of acute and chronic PAH exposure on cardiopulmonary mortality were examined within a Kitimat, Canada, aluminum smelter cohort (n = 7,026) linked to a national mortality database (1957–1999). No standardized mortality ratio was significantly elevated compared with the province's population. Smoking-adjusted internal comparisons were conducted using Cox regression for male subjects (n = 6,423). Ischemic heart disease (IHD) mortality (n = 281) was associated with cumulative benzo[a]pyrene (B(a)P) exposure (hazard ratio = 1.62, 95% confidence interval: 1.06, 2.46) in the highest category. A monotonic but nonsignificant trend was observed with chronic B(a)P exposure and acute myocardial infarction (n = 184). When follow-up was restricted to active employment, the hazard ratio for IHD was 2.39 (95% confidence interval: 0.95, 6.05) in the highest cumulative B(a)P category. The stronger associations observed during employment suggest that risk may not persist after exposure cessation. No associations with recent or current exposure were observed. IHD was associated with chronic (but not current) PAH exposure in a high-exposure occupational setting. Given the widespread workplace exposure to PAHs and heart disease's high prevalence, even modest associations produce a high burden. PMID:20702507

  1. Differences of acute versus chronic ethanol exposure on anxiety-like behavioral responses in zebrafish.

    PubMed

    Mathur, Priya; Guo, Su

    2011-06-01

    Zebrafish, a vertebrate model organism amenable to high throughput screening, is an attractive system to model and study the mechanisms underlying human diseases. Alcoholism and alcoholic medical disorders are among the most debilitating diseases, yet the mechanisms by which ethanol inflicts the disease states are not well understood. In recent years zebrafish behavior assays have been used to study learning and memory, fear and anxiety, and social behavior. It is important to characterize the effects of ethanol on zebrafish behavioral repertoires in order to successfully harvest the strength of zebrafish for alcohol research. One prominent effect of alcohol in humans is its effect on anxiety, with acute intermediate doses relieving anxiety and withdrawal from chronic exposure increasing anxiety, both of which have significant contributions to alcohol dependence. In this study, we assess the effects of both acute and chronic ethanol exposure on anxiety-like behaviors in zebrafish, using two behavioral paradigms, the Novel Tank Diving Test and the Light/Dark Choice Assay. Acute ethanol exposure exerted significant dose-dependent anxiolytic effects. However, withdrawal from repeated intermittent ethanol exposure disabled recovery from heightened anxiety. These results demonstrate that zebrafish exhibit different anxiety-like behavioral responses to acute and chronic ethanol exposure, which are remarkably similar to these effects of alcohol in humans. Because of the accessibility of zebrafish to high throughput screening, our results suggest that genes and small molecules identified in zebrafish will be of relevance to understand how acute versus chronic alcohol exposure have opposing effects on the state of anxiety in humans. Copyright © 2011 Elsevier B.V. All rights reserved.

  2. Acute Air Pollution Exposure and Risk of Suicide Completion

    PubMed Central

    Bakian, Amanda V.; Huber, Rebekah S.; Coon, Hilary; Gray, Douglas; Wilson, Phillip; McMahon, William M.; Renshaw, Perry F.

    2015-01-01

    Research into environmental factors associated with suicide has historically focused on meteorological variables. Recently, a heightened risk of suicide related to short-term exposure to airborne particulate matter was reported. Here, we examined the associations between short-term exposure to nitrogen dioxide, particulate matter, and sulfur dioxide and completed suicide in Salt Lake County, Utah (n = 1,546) from 2000 to 2010. We used a time-stratified case-crossover design to estimate adjusted odds ratios for the relationship between suicide and exposure to air pollutants on the day of the suicide and during the days preceding the suicide. We observed maximum heightened odds of suicide associated with interquartile-range increases in nitrogen dioxide during cumulative lag 3 (average of the 3 days preceding suicide; odds ratio (OR) = 1.20, 95% confidence interval (CI): 1.04, 1.39) and fine particulate matter (diameter ≤2.5 μm) on lag day 2 (day 2 before suicide; OR = 1.05, 95% CI: 1.01, 1.10). Following stratification by season, an increased suicide risk was associated with exposure to nitrogen dioxide during the spring/fall transition period (OR = 1.35, 95% CI: 1.09, 1.66) and fine particulate matter in the spring (OR = 1.28, 95% CI: 1.01, 1.61) during cumulative lag 3. Findings of positive associations between air pollution and suicide appear to be consistent across study locations with vastly different meteorological, geographical, and cultural characteristics. PMID:25673816

  3. Mutagenic potential of acute exposure to organophosphorus and organochlorine compounds.

    PubMed

    Vijayaraghavan, M; Nagarajan, B

    1994-04-01

    The cytogenetic and cytotoxic effects of the pesticides methyl parathion, Bayleton and Hinosan were evaluated in mammalian test systems. The frequency of chromosome aberrations and micronuclei in bone marrow cells and the arginase enzyme profile in the liver tend to show the genotoxicity of organophosphorus and organochlorine pesticides in a single-exposure response study. Methyl parathion was the most hazardous among the three, showing definite pathology in the livers of treated rats.

  4. Permeabilization of the nuclear envelope following nanosecond pulsed electric field exposure

    SciTech Connect

    Thompson, Gary L.; Roth, Caleb C.; Kuipers, Marjorie A.; Tolstykh, Gleb P.; Beier, Hope T.; Ibey, Bennett L.

    2016-01-29

    Permeabilization of cell membranes occurs upon exposure to a threshold absorbed dose (AD) of nanosecond pulsed electric fields (nsPEF). The ultimate, physiological bioeffect of this exposure depends on the type of cultured cell and environment, indicating that cell-specific pathways and structures are stimulated. Here we investigate 10 and 600 ns duration PEF effects on Chinese hamster ovary (CHO) cell nuclei, where our hypothesis is that pulse disruption of the nuclear envelope membrane leads to observed cell death and decreased viability 24 h post-exposure. To observe short-term responses to nsPEF exposure, CHO cells have been stably transfected with two fluorescently-labeled proteins known to be sequestered for cellular chromosomal function within the nucleus – histone-2b (H2B) and proliferating cell nuclear antigen (PCNA). H2B remains associated with chromatin after nsPEF exposure, whereas PCNA leaks out of nuclei permeabilized by a threshold AD of 10 and 600 ns PEF. A downturn in 24 h viability, measured by MTT assay, is observed at the number of pulses required to induce permeabilization of the nucleus. - Highlights: • The ability of nsPEF to damage nuclear structures within cells is investigated. • Leakage of proliferating nuclear antigen from nuclei is induced by nsPEF. • High doses of nsPEF disrupt cortical lamin and cause chromatin decompaction. • Histone H2B remains attached to chromatin following nsPEF exposure. • DNA does not leak out of nsPEF-permeabilized nuclei.

  5. Acute illness-induced behavioral alterations are similar to those observed during withdrawal from acute alcohol exposure

    PubMed Central

    Richey, Laura; Doremus-Fitzwater, Tamara L.; Buck, Hollin M.; Deak, Terrence

    2012-01-01

    Exposure to an immunogen results in a constellation of behavioral changes collectively referred to as “sickness behaviors,” with alterations in cytokine expression previously shown to contribute to this sickness response. Since behaviors observed during ethanol withdrawal are strikingly similar to sickness behaviors, we hypothesized that behavioral manifestations of ethanol withdrawal might be an expression of sickness behaviors induced by ethanol-related changes in peripheral and/or central cytokine expression. Accordingly, behaviors exhibited during a modified social investigation test were first characterized in male rats following an acute injection of lipopolysaccharide (LPS; 100 μg/kg). Subsequently, behavioral changes after either a high (4-g/kg; Experiment 2) or low dose (0.5 g/kg; Experiment 3) of ethanol were also examined in the same social investigation test, as well as in the forced-swim test (FST; Experiment 4). Results from these experiments demonstrated similar reductions in both exploration and social investigatory behavior during acute illness and ethanol withdrawal, while a seemingly paradoxical decrease in immobility was observed in the FST during acute ethanol withdrawal. In follow-up studies, neither indomethacin (Experiment 5) nor interleukin-1 receptor antagonist (Experiment 6) pre-exposure reversed the ethanol withdrawal-induced behavioral changes observed in this social investigation test. Taken together, these studies demonstrate that the behavioral sequelae of acute illness and ethanol withdrawal are similar in nature, while antagonist studies suggest that these behavioral alterations are not reversed by blockade of IL-1 receptors or inhibition of prostaglandin synthesis. Though a direct mechanistic link between cytokines and the expression of acute ethanol withdrawal-related behaviors has yet to be found, future studies examining the involvement of brain cytokines as potential mediators of ethanol effects are greatly needed. PMID

  6. DISTRIBUTION OF 14C-ATRAZINE FOLLOWING AN ACUTE LACTATIONAL EXPOSURE IN THE WISTAR RAT.

    EPA Science Inventory

    The purpose of the present study was to examine the distribution of atrazine in the lactating dam and suckling neonate following an acute exposure to either 2 or 4 mg/kg 14C-atrazine (14C-ATR) by gavage. 14C-ATR was administered to the nursing dam on postnatal day 3 by oral gavag...

  7. The effect of chronic ammonia exposure on acute phase proteins, immunoglobulin and cytokines in laying hens

    USDA-ARS?s Scientific Manuscript database

    Ammonia is a potential health hazard to both humans and animals, causing systemic low-grade inflammation based on its levels and durations. The objective of this study was to examine the effect of 45 weeks of exposure to 30 ppm NH3 on the concentrations of acute phase proteins, immunoglobulins and c...

  8. Self-reported acute health symptoms and exposure to companion animals#

    EPA Science Inventory

    Self-reported acute health symptoms and exposure to companion animalsWhitney S. Krueger1,2, Elizabeth D. Hilborn2, Timothy J. Wade21Oak Ridge Institute for Science and Education, Oak Ridge, Tennessee, USA2Environmental Public Health Division, Office of Research and Development, U...

  9. Neurobehavorial effects of acute exposure to four solvents: meta-abalyses

    EPA Science Inventory

    Meta-and re-analyses of the available data for the neurobehavioral effects of acute inhalation exposure to toluene were reported by Benignus et al. (2007). The present study was designed to test the generality of the toluene results in as many other solvents as possible by furthe...

  10. TOXICITY PATHWAY ANALYSIS IN AGING BROWN NORWAY RAT BRAIN FOLLOWING ACUTE TOLUENE EXPOSURE

    EPA Science Inventory

    The influence of aging on susceptibility to environmental stressors is poorly understood. To investigate the contribution of different life stages on response to toxicants, we examined the effects of acute exposure by oral gavage of the volatile organic solvent toluene (0.00, 0.3...

  11. DISTRIBUTION OF 14C-ATRAZINE FOLLOWING AN ACUTE LACTATIONAL EXPOSURE IN THE WISTAR RAT.

    EPA Science Inventory

    The purpose of the present study was to examine the distribution of atrazine in the lactating dam and suckling neonate following an acute exposure to either 2 or 4 mg/kg 14C-atrazine (14C-ATR) by gavage. 14C-ATR was administered to the nursing dam on postnatal day 3 by oral gavag...

  12. ACUTE BEHAVORIAL EFFECTS FROM EXPOSURE TO TWO-STROKE ENGINE EXHAUST

    EPA Science Inventory

    Benefits of changing from two-stroke to four-stroke engines (and other remedial requirements) can be evaluated (monetized) from the standpoint of acute behavioral effects of human exposure to exhaust from these engines. The monetization process depends upon estimates of the magn...

  13. CARDIOVASCULAR INJURY FROM ACUTE AND REPEATED EXPOSURE TO PARTICULATE MATTER (PM): POTENTIAL ROLE OF ZINC

    EPA Science Inventory

    CARDIOVASCULAR INJURY FROM ACUTE AND REPEATED EXPOSURE TO PARTICULATE MATTER (PM): POTENTIAL ROLE OF ZINC. UP Kodavanti, MC Schladweiler, AD Ledbetter, RH Jaskot, PS Gilmour, DC Christiani, WP Watkinson, DL Costa, JK McGee, A Nyska. NHEERL, USEPA, RTP, NC; CEMALB, UNC, Chapel Hil...

  14. Striatal dopamine dynamics in mice following acute and repeated toluene exposure.

    PubMed

    Apawu, Aaron K; Mathews, Tiffany A; Bowen, Scott E

    2015-01-01

    The abused inhalant toluene has potent behavioral effects, but only recently has progress been made in understanding the neurochemical actions that mediate the action of toluene in the brain. Available evidence suggests that toluene inhalation alters dopamine (DA) neurotransmission, but toluene's mechanism of action is unknown. The present study evaluated the effect of acute and repeated toluene inhalation (0, 2,000, or 4,000 ppm) on locomotor activity as well as striatal DA release and uptake using slice fast-scan cyclic voltammetry. Acutely, 2,000 and 4,000 ppm toluene increased locomotor activity, while neurochemically only 4,000 ppm toluene potentiated electrically evoked DA release across the caudate-putamen and the nucleus accumbens. Repeated administration of toluene resulted in sensitization to toluene's locomotor activity effects. Brain slices obtained from mice repeatedly exposed to toluene demonstrated no difference in stimulated DA release in the caudate-putamen as compared to control animals. Repeated exposure to 2,000 and 4,000 ppm toluene caused a concentration-dependent decrease of 25-50 % in evoked DA release in the nucleus accumbens core and shell relative to air-exposed mice. These voltammetric neurochemical findings following repeated toluene exposure suggest that there may be a compensatory downregulation of the DA system. Acute or repeated toluene exposure had no effect on the DA uptake kinetics. Taken together, these results demonstrate that acute toluene inhalation potentiates DA release, while repeated toluene exposure attenuates DA release in the nucleus accumbens only.

  15. In Utero Exposure to Lipopolysaccharide Alters the Postnatal Acute Phase Response in Beef Heifers

    USDA-ARS?s Scientific Manuscript database

    This study was designed to determine the potential effect of prenatal lipopolysaccharide (LPS) exposure on the postnatal acute phase response (APR) to an LPS challenge in heifers. Pregnant crossbred cows (n = 50) were separated into prenatal immune stimulation (PIS; n = 25; administered 0.1 microgr...

  16. TOXICITY PATHWAY ANALYSIS IN AGING BROWN NORWAY RAT BRAIN FOLLOWING ACUTE TOLUENE EXPOSURE

    EPA Science Inventory

    The influence of aging on susceptibility to environmental stressors is poorly understood. To investigate the contribution of different life stages on response to toxicants, we examined the effects of acute exposure by oral gavage of the volatile organic solvent toluene (0.00, 0.3...

  17. Neurobehavorial effects of acute exposure to four solvents: meta-abalyses

    EPA Science Inventory

    Meta-and re-analyses of the available data for the neurobehavioral effects of acute inhalation exposure to toluene were reported by Benignus et al. (2007). The present study was designed to test the generality of the toluene results in as many other solvents as possible by furthe...

  18. CARDIOVASCULAR INJURY FROM ACUTE AND REPEATED EXPOSURE TO PARTICULATE MATTER (PM): POTENTIAL ROLE OF ZINC

    EPA Science Inventory

    CARDIOVASCULAR INJURY FROM ACUTE AND REPEATED EXPOSURE TO PARTICULATE MATTER (PM): POTENTIAL ROLE OF ZINC. UP Kodavanti, MC Schladweiler, AD Ledbetter, RH Jaskot, PS Gilmour, DC Christiani, WP Watkinson, DL Costa, JK McGee, A Nyska. NHEERL, USEPA, RTP, NC; CEMALB, UNC, Chapel Hil...

  19. Self-reported acute health symptoms and exposure to companion animals#

    EPA Science Inventory

    Self-reported acute health symptoms and exposure to companion animalsWhitney S. Krueger1,2, Elizabeth D. Hilborn2, Timothy J. Wade21Oak Ridge Institute for Science and Education, Oak Ridge, Tennessee, USA2Environmental Public Health Division, Office of Research and Development, U...

  20. ACUTE BEHAVORIAL EFFECTS FROM EXPOSURE TO TWO-STROKE ENGINE EXHAUST

    EPA Science Inventory

    Benefits of changing from two-stroke to four-stroke engines (and other remedial requirements) can be evaluated (monetized) from the standpoint of acute behavioral effects of human exposure to exhaust from these engines. The monetization process depends upon estimates of the magn...

  1. A Method for Quantifying the Acute Health Impacts of Residential Non-Biological Exposure Via Inhalation

    SciTech Connect

    Logue, Jennifer M.; Sherman, Max H.; Singer, Bret C.

    2014-08-01

    The inability to monetize the health costs of acute exposures in homes and the benefits of various control options is a barrier to justifying policies and approaches that can reduce exposure and improve health.We synthesized relationships between short-term outdoor concentration changes and health outcomes to estimate the health impacts of short-term in-home exposures. Damage and cost impacts of specific health outcomes were taken from the literature. We assessed the impact of vented and non-vented residential natural gas cooking burners on Southern California occupants for two pollutants (NO2 and CO).

  2. Acute exposure to waterborne psychoactive drugs attract zebrafish.

    PubMed

    Abreu, Murilo S; Giacomini, Ana Cristina V; Gusso, Darlan; Rosa, João G S; Koakoski, Gessi; Kalichak, Fabiana; Idalêncio, Renan; Oliveira, Thiago A; Barcellos, Heloísa H A; Bonan, Carla D; Barcellos, Leonardo J G

    2016-01-01

    Psychotropic medications are widely used, and their prescription has increased worldwide, consequently increasing their presence in aquatic environments. Therefore, aquatic organisms can be exposed to psychotropic drugs that may be potentially dangerous, raising the question of whether these drugs are attractive or aversive to fish. To answer this question, adult zebrafish were tested in a chamber that allows the fish to escape or seek a lane of contaminated water. These attraction and aversion paradigms were evaluated by exposing the zebrafish to the presence of acute contamination with these compounds. The zebrafish were attracted by certain concentrations of diazepam, fluoxetine, risperidone and buspirone, which were most likely detected by olfaction, because this behavior was absent in anosmic fish. These findings suggest that despite their deleterious effects, certain psychoactive drugs attract fish. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Glucocorticoid exposure alters the pathogenesis of Theiler’s murine encephalomyelitis virus during acute infection

    PubMed Central

    Young, Erin E.; Prentice, Thomas W.; Satterlee, Danielle; McCullough, Heath; Sieve, Amy N.; Johnson, Robin R.; Welsh, Thomas H.; Welsh, C. Jane R.; Meagher, Mary W.

    2008-01-01

    Previous research has shown that chronic restraint stress exacerbates Theiler’s virus infection, a murine model for CNS inflammation and multiple sclerosis. The current set of experiments was designed to evaluate the potential role of glucocorticoids in the deleterious effects of restraint stress on acute CNS inflammatory disease. Exposure to chronic restraint stress resulted in elevated levels of corticosterone as well as increased clinical scores and weight loss (Experiment 1). In addition, corticosterone administration alone exacerbated behavioral signs of TMEV-induced sickness (i.e. decreased body weight, increased symptoms of encephalitis, and increased mortality) and reduced inflammation in the CNS (Experiment 2). Infected subjects receiving exogenous corticosterone showed exacerbation of acute phase measures of sickness and severe mortality as well as decreased viral clearance from CNS (Experiment 3). These findings indicate that corticosterone exposure alone is sufficient to exacerbate acute CNS inflammatory disease. PMID:18538803

  4. Prenatal and acute cocaine exposure affects neural responses and habituation to visual stimuli

    PubMed Central

    Riley, Elizabeth; Kopotiyenko, Konstantin; Zhdanova, Irina

    2015-01-01

    Psychostimulants have many effects on visual function, from adverse following acute and prenatal exposure to therapeutic on attention deficit. To determine the impact of prenatal and acute cocaine exposure on visual processing, we studied neuronal responses to visual stimuli in two brain regions of a transgenic larval zebrafish expressing the calcium indicator GCaMP-HS. We found that both red light (LF) and dark (DF) flashes elicited similar responses in the optic tectum neuropil (TOn), while the dorsal telencephalon (dTe) responded only to LF. Acute cocaine (0.5 μM) reduced neuronal responses to LF in both brain regions but did not affect responses to DF. Repeated stimulus presentation (RSP) led to habituation of dTe neurons to LF. Acute cocaine prevented habituation. TOn habituated to DF, but not LF, and DF habituation was not modified by cocaine. Remarkably, prenatal cocaine exposure (PCE) prevented the effects of acute cocaine on LF response amplitude and habituation later in development in both brain regions, but did not affect DF responses. We discovered that, in spite of similar neural responses to LF and DF in the TO (superior colliculus in mammals), responses to LF are more complex, involving dTe (homologous to the cerebral cortex), and are more vulnerable to cocaine. Our results demonstrate that acute cocaine exposure affects visual processing differentially by brain region, and that PCE modifies zebrafish visual processing in multiple structures in a stimulus-dependent manner. These findings are in accordance with the major role that the optic tectum and cerebral cortex play in sustaining visual attention, and support the hypothesis that modification of these areas by PCE may be responsible for visual deficits noted in humans. This model offers new methodological approaches for studying the adverse and therapeutic effects of psychostimulants on attention, and for the development of new pharmacological interventions. PMID:26379509

  5. Responses of the soft coral Xenia elongata following acute exposure to a chemical dispersant.

    PubMed

    Studivan, Michael S; Hatch, Walter I; Mitchelmore, Carys L

    2015-01-01

    Limited toxicology data are available regarding oil dispersant exposure to coral species. Corexit® EC9500A (Corexit) is a commonly applied dispersant most well known for its use after the Deepwater Horizon spill in April, 2010. There is limited evidence that Corexit can cause a bleaching response in corals. The aims of the study were: (1) to determine the extent of bleaching after acute 24 h and 72 h exposures of sublethal concentrations (0-50 ppm) of Corexit to the pulsing soft coral Xenia elongata and (2) to investigate a percent symbiont loss calculation using zooxanthellae density. The percent symbiont loss calculation was compared to a traditional metric of normalizing zooxanthellae density to soluble protein content. Percent symbiont loss was an effective measure of coral stress in acute Corexit exposures, while protein normalized zooxanthellae density was more variable. The bleaching data suggest a positive relationship between dispersant concentration and percent symbiont loss, culminating in excessive tissue necrosis and coral mortality within 72 h in high concentration exposures (p < 0.001). Percent beaching ranged from 25% in 5 ppm exposures to 100% in 50 ppm exposures. Corexit also caused a significant decrease in pulse activity (p < 0.0001) and relative oxygen saturation (p < 0.001), possibly indicating a reduction in photosynthetic efficiency. This study and other similar research indicate that dispersant exposure is highly damaging to marine organisms, including ecologically important coral species.

  6. Exhaled nitric oxide decreases upon acute exposure to high-altitude hypoxia.

    PubMed

    Brown, Daniel E; Beall, Cynthia M; Strohl, Kingman P; Mills, Phoebe S

    2006-01-01

    Nitric oxide (NO) is a vasodilator that plays a role in blood flow and oxygen delivery. Acute hypoxia down regulates NO synthesis, a response that may exacerbate hypoxic stress by decreasing blood flow. This study was designed to test the hypotheses that pulmonary NO decreases upon acute exposure to high-altitude hypoxia and that relatively low levels of NO at altitude are associated with greater stress as reflected in more symptoms of acute mountain sickness (AMS). A sample of 47 healthy, adult, nonsmoking, sea-level residents provided measurements at sea level, at 2,800 m, and at 0-, 2-, and 3-h exposure times at 4,200 m altitude on Mauna Kea, Hawaii. Measurements were made of exhaled NO, oxygen saturation of hemoglobin, heart rate, and reported symptoms of AMS. The partial pressure of NO concentration in exhaled breath decreased significantly from a sea level mean of 4.2 nmHg to 3.8 nmHg at 2,800 m and 3.4 nmHg at 4,200 m. NO concentration in exhaled breath did not change significantly over a 3-h exposure at 4,200 m and recovered to pre-exposure baseline upon return to sea level. There was no significant association between the level of NO exhaled and the number of self-reported symptoms of AMS during this brief exposure. Am. J. Hum. Biol. 18:196-202, 2006. (c) 2006 Wiley-Liss, Inc.

  7. Effects of Acute Exposure to Sublethal Waterborne Cadmium on Energy Homeostasis in Silver Carp (Hypophthalmichthys molitrix).

    PubMed

    Pi, Jie; Li, Xuelin; Zhang, Ting; Li, Deliang

    2016-10-01

    Effects of acute exposure to sublethal waterborne cadmium (Cd) on energy homeostasis in filter-feeding fishes have rarely been studied. The response patterns of energy substances were investigated in juvenile silver carp (Hypophthalmichthys molitrix) exposed to sublethal waterborne Cd for 96 h. The results showed the 96hLC50 of Cd on juvenile silver carp was 1.723 mg/L. Sublethal acute exposure of Cd significantly affected the energy homeostasis of juvenile silver carp, including increase in plasma glucose and lactate, and decrease in plasma triglyceride, muscle glycogen and triglyceride and liver glycogen. The results indicated that glycogen and triglyceride prior to protein were mobilized to meet the increased demands for detoxication and repair mechanism to sublethal waterborne Cd exposure, and glycogen level depleted faster and restored slower in the liver than in the white muscle in juvenile silver carp.

  8. Acute and Chronic Exposure to CO2 in Space Flight

    NASA Technical Reports Server (NTRS)

    Alexander, D.; Wu, J.; Barr, Y. R.; Watkins, S. D.

    2010-01-01

    Spacecraft and space stations, similar to other habitable confined spaces such as submarines, need to provide a breathable atmosphere for their inhabitants. The inevitable production of CO2 during respiration necessitates life support systems that "scrub" the atmosphere and lower CO2 levels. Due to operational limitations associated with space flight (limited mass, volume, power, and consumables) CO2 is not scrubbed down to its terrestrial equivalent of 0.03% CO2 (ppCO2 of 0.23 mmHg), but is kept below 0.7% (ppCO2 of 5.3 mmHg), a level established in NASA s 180-day mission Spacecraft Maximum Allowable Concentration (SMAC) to be safe and unlikely to cause symptoms. Reports of space flight crewmembers becoming symptomatic with headaches, fatigue, and malaise at levels below those known to cause such symptoms terrestrially has prompted studies measuring the levels of CO2 on both the space shuttle and the space station. Data from cabin atmosphere sampling were collected on space shuttle missions STS-113, STS-122, STS-123, and International Space Station Expeditions 12-15 and 17, and the measured CO2 levels were then correlated to symptoms reported by the crew. The results indicate that a correlation exists between CO2 levels and symptomatology, however causality cannot be established at this time. While the short-term effects of elevated CO2 exposure are well known terrestrially, less is known regarding potential long-term effects of prolonged exposure to a CO2-rich environment or how the physiological changes caused by microgravity may interact with such exposures. Other challenges include limitations in the CO2 monitors used, lack of convection in the microgravity environment, and formation of localized CO2 pockets. As it is unclear if the unique environment of space increases sensitivity to CO2 or if other confounding factors are present, further research is planned to elucidate these points. At the same time, efforts are underway to update the SMAC to a lower level

  9. Tracking patient radiation exposure: challenges to integrating nuclear medicine with other modalities

    PubMed Central

    Mercuri, Mathew; Rehani, Madan M.; Einstein, Andrew J.

    2013-01-01

    The cumulative radiation exposure to the patient from multiple radiological procedures can place some individuals at significantly increased risk for stochastic effects and tissue reactions. Approaches, such as those in the International Atomic Energy Agency’s Smart Card program, have been developed to track cumulative radiation exposures to individuals. These strategies often rely on the availability of structured dose reports, typically found in the DICOM header. Dosimetry information is currently readily available for many individual x-ray based procedures. Nuclear medicine, of which nuclear cardiology constitutes the majority of the radiation burden in the U.S., currently lags behind x-ray based procedures with respect to reporting of radiation dosimetric information. This paper discusses qualitative differences between nuclear medicine and x-ray based procedures, including differences in the radiation source and measurement of its strength, the impact of biokinetics on dosimetry, and the capability of current scanners to record dosimetry information. These differences create challenges in applying monitoring and reporting strategies used in x-ray based procedures to nuclear medicine, and integrating dosimetry information across modalities. A concerted effort by the medical imaging community, dosimetry specialists and manufacturers of imaging equipment is required to develop strategies to improve the reporting of radiation dosimetry data in nuclear medicine. Some ideas on how to address this issue are suggested. PMID:22695788

  10. Long-Term Ozone Exposure Increases the Risk of Developing the Acute Respiratory Distress Syndrome.

    PubMed

    Ware, Lorraine B; Zhao, Zhiguo; Koyama, Tatsuki; May, Addison K; Matthay, Michael A; Lurmann, Fred W; Balmes, John R; Calfee, Carolyn S

    2016-05-15

    The contribution of air pollution to the risk of acute respiratory distress syndrome (ARDS) is unknown. We studied 1,558 critically ill patients enrolled in a prospective observational study at a tertiary medical center who lived less than 50 km from an air quality monitor and had an ARDS risk factor. Pollutant exposures (ozone, NO2, SO2, particulate matter < 2.5 μm, particulate matter < 10 μm) were assessed by weighted average of daily levels from the closest monitors for the prior 3 years. Associations between pollutant exposure and ARDS risk were evaluated by logistic regression controlling for age, race, sex, smoking, alcohol, insurance status, rural versus urban residence, distance to study hospital, and Acute Physiology and Chronic Health Evaluation II. The incidence of ARDS increased with increasing ozone exposure: 28% in the lowest exposure quartile versus 32, 40, and 42% in the second, third, and fourth quartiles (P < 0.001). In a logistic regression model controlling for potential confounders, ozone exposure was associated with risk of ARDS in the entire cohort (odds ratio, 1.58 [95% confidence interval, 1.27-1.96]) and more strongly associated in the subgroup with trauma as their ARDS risk factor (odds ratio, 2.26 [95% confidence interval, 1.46-3.50]). There was a strong interaction between ozone exposure and current smoking status (P = 0.007). NO2 exposure was also associated with ARDS but not independently of ozone exposure. SO2, particulate matter less than 2.5 μm, and particulate matter less than 10 μm were not associated with ARDS. Long-term ozone exposure is associated with development of ARDS in at-risk critically ill patients, particularly in trauma patients and current smokers. Ozone exposure may represent a previously unrecognized environmental risk factor for ARDS.

  11. Acute theophylline exposure modulates breathing activity through a cervical contusion.

    PubMed

    Hoy, Kevin C; Alilain, Warren J

    2015-09-01

    Cervical spinal contusion injuries are the most common form of spinal cord injury (>50%) observed in humans. These injuries can result in the impaired ability to breathe. In this study we examine the role of theophylline in the rescue of breathing behavior after a cervical spinal contusion. Previous research in the C2 hemisection model has shown that acute administration of theophylline can rescue phrenic nerve activity and diaphragmatic EMG on the side ipsilateral to injury. However, this effect is dependent on intact and uninjured pathways. In this study we utilized a cervical contusion injury model that more closely mimics the human condition. This injury model can determine the effectiveness of therapeutic interventions, in this case theophylline, on the isolated contused pathways of the spinal cord. Three weeks after a 150 kD C3/4 unilateral contusion subjects received a 15 mg/kg dose of theophylline prior to a contralateral C2 hemisection. Subjects that received theophylline were able to effectively utilize damaged pathways to breathe for up to 2 min, while subjects treated with saline were unable to support ventilation. Through these experiments, we demonstrate that theophylline can make injured pathways that mediate breathing more effective and therefore, suggest a potential therapeutic role in the critical time points immediately after injury. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Toxicity of white phosphorus to waterfowl: acute exposure in mallards

    USGS Publications Warehouse

    Sparling, D.W.; Gustafson, M.; Klein, P.; Karouna-Renier, N.

    1997-01-01

    As part of an effort to understand extensive, white phosphorus (P4)-induced waterfowl mortality at Eagle River Flats, Fort Richardson, Alaska, we conducted a number of acute toxicity tests using penned mallards (Anas platyrhynchos) in 1993 and 1994. The 24-hr median lethal dose (LD50) for P4 dissolved in oil was 6.46 mg/kg in adult males and 6.96 mg/kg in adult females. Although the median lethal doses were not statistically different, the female dose-response curve had a statistically shallower slope than that of males. The LD50 for the ecologically more relevant pelletized form of P4 in adult males was 4.05 mg/kg. In mallards, one mechanism of P4 toxicity caused rapid (3 to 10 hr) mortality and had signs consistent with anoxia. A second, slower acting mechanism resulted in hepatic and renal pathology including extensive fat deposition in the liver and cellular necrosis. White phosphorus accumulated in adipose tissues, but only for a few days.

  13. Investigation of public exposure resulted from the radioiodine delay tank facility of nuclear medicine department

    SciTech Connect

    Yusof, Mohd Fahmi Mohd Ali, Abdul Muhaimin Mat; Abdullah, Reduan; Idris, Abdullah Waidi

    2016-01-22

    The study is carried out to assess the exposure rate that could contribute to public exposure in a radioiodine ward delay tank facility of Radiotherapy, Oncology and Nuclear Medicine, Department, Hospital Universiti Sains Malaysia (HUSM). The exposure rate at several locations including the delay tank room, doorway and at the public walking route was measured using Victoreen 415P-RYR survey meter. The radioactive level of the {sup 131}I waste was measured using Captus 3000 well counting system. The results showed that exposure rate and total count of the delay tank sample increased when the radioiodine ward was fully occupied with patient and reduced when the ward was vacant. Occupancy of radioiodine ward for two consecutive weeks had dramatically increased the exposure rate around the delay tank and radioactive level of {sup 131}I waste. The highest exposure rate and radioactive level was recorded when the ward was occupied for two consecutive weeks with 177.00 µR/h and 58.36 kcpm respectively. The exposure rate decreased 15.76 % when the door of the delay tank room was closed. The exposure rate at public walking route decreased between 15.58 % and 36.92 % as the distance increased between 1 and 3 m.

  14. Investigation of public exposure resulted from the radioiodine delay tank facility of nuclear medicine department

    NASA Astrophysics Data System (ADS)

    Yusof, Mohd Fahmi Mohd; Ali, Abdul Muhaimin Mat; Abdullah, Reduan; Idris, Abdullah Waidi

    2016-01-01

    The study is carried out to assess the exposure rate that could contribute to public exposure in a radioiodine ward delay tank facility of Radiotherapy, Oncology and Nuclear Medicine, Department, Hospital Universiti Sains Malaysia (HUSM). The exposure rate at several locations including the delay tank room, doorway and at the public walking route was measured using Victoreen 415P-RYR survey meter. The radioactive level of the 131I waste was measured using Captus 3000 well counting system. The results showed that exposure rate and total count of the delay tank sample increased when the radioiodine ward was fully occupied with patient and reduced when the ward was vacant. Occupancy of radioiodine ward for two consecutive weeks had dramatically increased the exposure rate around the delay tank and radioactive level of 131I waste. The highest exposure rate and radioactive level was recorded when the ward was occupied for two consecutive weeks with 177.00 µR/h and 58.36 kcpm respectively. The exposure rate decreased 15.76 % when the door of the delay tank room was closed. The exposure rate at public walking route decreased between 15.58 % and 36.92 % as the distance increased between 1 and 3 m.

  15. Structural and Functional Changes of the Human Macula during Acute Exposure to High Altitude

    PubMed Central

    Fischer, M. Dominik; Willmann, Gabriel; Schatz, Andreas; Schommer, Kai; Zhour, Ahmad; Zrenner, Eberhart; Bartz-Schmidt, Karl U.; Gekeler, Florian

    2012-01-01

    Background This study aimed to quantify structural and functional changes at the macula during acute exposure to high altitude and to assess their structure/function relationship. This work is related to the Tuebingen High Altitude Ophthalmology (THAO) study. Methodology/Principal Findings Spectral domain optical coherence tomography and microperimetry were used to quantify changes of central retinal structure and function in 14 healthy subjects during acute exposure to high altitude (4559 m). High-resolution volume scans and fundus-controlled microperimetry of the posterior pole were performed in addition to best-corrected visual acuity (BCVA) measurements and assessment of acute mountain sickness. Analysis of measurements at altitude vs. baseline revealed increased total retinal thickness (TRT) in all four outer ETDRS grid subfields during acute altitude exposure (TRTouter = 2.80±1.00 μm; mean change±95%CI). This change was inverted towards the inner four subfields (TRTinner = −1.89±0.97 μm) with significant reduction of TRT in the fovea (TRTfoveal = −6.62±0.90 μm) at altitude. BCVA revealed no significant difference compared to baseline (0.06±0.08 logMAR). Microperimetry showed stable mean sensitivity in all but the foveal subfield (MSfoveal = −1.12±0.68 dB). At baseline recordings before and >2 weeks after high altitude exposure, all subjects showed equal levels with no sign of persisting structural or functional sequels. Conclusions/Significance During acute exposure to high altitude central retinal thickness is subject to minor, yet statistically significant changes. These alterations describe a function of eccentricity with an increase in regions with relatively higher retinal nerve fiber content and vascular arcades. However, these changes did not correlate with measures of central retinal function or acute mountain sickness. For the first time a quantitative approach has been used to assess these changes during acute, non

  16. Parkinson's disease in relation to pesticide exposure and nuclear encoded mitochondrial complex I gene variants.

    PubMed

    Corder, Elizabeth H; Mellick, George D

    2006-01-01

    Parkinson's disease (PD) is a common age-related neurodegenerative disorder thought to result from the integrated effects of genetic background and exposure to neuronal toxins. Certain individual nuclear-encoded mitochondrial complex I gene polymorphisms were found to be associated with approximately 2-fold risk variation in an Australian case-control sample. We further characterized this sample of 306 cases and 321 controls to determine the mutual information contained in the 22 SNPs and, additionally, level of pesticide exposure: five distinct risk sets were identified using grade-of-membership analysis. Of these, one was robust to pesticide exposure (I), three were vulnerable (II, III, IV), and another (V) denoted low risk for unexposed persons. Risk for individual subjects varied > 16-fold according to level of membership in the vulnerable groups. We conclude that inherited variation in mitochondrial complex I genes and pesticide exposure together modulate risk for PD.

  17. Acute myeloid and chronic lymphoid leukaemias and exposure to low-level benzene among petroleum workers

    PubMed Central

    Rushton, L; Schnatter, A R; Tang, G; Glass, D C

    2014-01-01

    Background: High benzene exposure causes acute myeloid leukaemia (AML). Three petroleum case–control studies identified 60 cases (241 matched controls) for AML and 80 cases (345 matched controls) for chronic lymphoid leukaemia (CLL). Methods: Cases were classified and scored regarding uncertainty by two haematologists using available diagnostic information. Blinded quantitative benzene exposure assessment used work histories and exposure measurements adjusted for era-specific circumstances. Statistical analyses included conditional logistic regression and penalised smoothing splines. Results: Benzene exposures were much lower than previous studies. Categorical analyses showed increased ORs for AML with several exposure metrics, although patterns were unclear; neither continuous exposure metrics nor spline analyses gave increased risks. ORs were highest in terminal workers, particularly for Tanker Drivers. No relationship was found between benzene exposure and risk of CLL, although the Australian study showed increased risks in refinery workers. Conclusion: Overall, this study does not persuasively demonstrate a risk between benzene and AML. A previously reported strong relationship between myelodysplastic syndrome (MDS) (potentially previously reported as AML) at our study's low benzene levels suggests that MDS may be the more relevant health risk for lower exposure. Higher CLL risks in refinery workers may be due to more diverse exposures than benzene alone. PMID:24357793

  18. Acute health effects after exposure to chlorine gas released after a train derailment.

    PubMed

    Van Sickle, David; Wenck, Mary Anne; Belflower, Amy; Drociuk, Dan; Ferdinands, Jill; Holguin, Fernando; Svendsen, Erik; Bretous, Lena; Jankelevich, Shirley; Gibson, James J; Garbe, Paul; Moolenaar, Ronald L

    2009-01-01

    In January 2005, a train derailment on the premises of a textile mill in South Carolina released 42 to 60 tons of chlorine gas in the middle of a small town. Medical records and autopsy reports were reviewed to describe the clinical presentation, hospital course, and pathology observed in persons hospitalized or deceased as a result of chlorine gas exposure. Eight persons died before reaching medical care; of the 71 persons hospitalized for acute health effects as a result of chlorine exposure, 1 died in the hospital. The mean age of the hospitalized persons was 40 years (range, 4 months-76 years); 87% were male. The median duration of hospitalization was 4 days (range, 1-29 days). Twenty-five (35%) persons were admitted to the intensive care unit; the median length of stay was 3 days. Many surviving victims developed significant pulmonary signs and severe airway inflammation; 41 (58%) hospitalized persons met PO2/FiO2 criteria for acute respiratory distress syndrome or acute lung injury. During their hospitalization, 40 (57%) developed abnormal x-ray findings, 74% of those within the first day. Hypoxia on room air and PO2/FiO2 ratio predicted severity of outcome as assessed by the duration of hospitalization and the need for intensive care support. This community release of chlorine gas caused widespread exposure and resulted in significant acute health effects and substantial health care requirements. Pulse oximetry and arterial blood gas analysis provided early indications of outcome severity.

  19. Acute health effects after exposure to chlorine gas released after a train derailment⋆

    PubMed Central

    Van Sickle, David; Wenck, Mary Anne; Belflower, Amy; Drociuk, Dan; Ferdinands, Jill; Holguin, Fernando; Svendsen, Erik; Bretous, Lena; Jankelevich, Shirley; Gibson, James J.; Garbe, Paul; Moolenaar, Ronald L.

    2015-01-01

    In January 2005, a train derailment on the premises of a textile mill in South Carolina released 42 to 60 tons of chlorine gas in the middle of a small town. Medical records and autopsy reports were reviewed to describe the clinical presentation, hospital course, and pathology observed in persons hospitalized or deceased as a result of chlorine gas exposure. Eight persons died before reaching medical care; of the 71 persons hospitalized for acute health effects as a result of chlorine exposure, 1 died in the hospital. The mean age of the hospitalized persons was 40 years (range, 4 months-76 years); 87% were male. The median duration of hospitalization was 4 days (range, 1-29 days). Twenty-five (35%) persons were admitted to the intensive care unit; the median length of stay was 3 days. Many surviving victims developed significant pulmonary signs and severe airway inflammation; 41 (58%) hospitalized persons met Po2/Fio2 criteria for acute respiratory distress syndrome or acute lung injury. During their hospitalization, 40 (57%) developed abnormal x-ray findings, 74% of those within the first day. Hypoxia on room air and Po2/Fio2 ratio predicted severity of outcome as assessed by the duration of hospitalization and the need for intensive care support. This community release of chlorine gas caused widespread exposure and resulted in significant acute health effects and substantial health care requirements. Pulse oximetry and arterial blood gas analysis provided early indications of outcome severity. PMID:19041527

  20. Factors affecting the estimated probabilistic acute dietary exposure to captan from apple consumption.

    PubMed

    Zentai, A; Sali, J; Szabó, I J; Szeitzné-Szabó, M; Ambrus, A; Vásárhelyi, A

    2013-01-01

    The effect of the number of pesticide residue values below the LOQ/LOD of analytical methods, the variability of residues in individual fruits, mass of fruit units and the number of bootstrap iterations was studied on the probabilistically estimated acute exposure of consumers. The 4720 daily apple consumption data and the results of 1239 apple sample analyses for captan residues, performed within the Hungarian monitoring programme between 2005 and 2011, were used in this study as model matrix. Up to about 95th percentile exposure (µg/(kg bw·day)), simply multiplying each residue in composite samples with each consumption value gave similar estimates to those obtained with the complex procedure taking also into account the mass of and residues in individual fruits. However, the exposure above the 95th percentile calculated with the complex procedure gradually increased with increasing percentile level compared to the simple procedure. Including the high number of non-detects reduced the estimated exposure, which was the highest when only the residues measured in treated fruits were taken into account. The number of bootstrap iterations between 100 and 10,000 did not significantly affect the calculated exposure. The 99.99th percentile exposure amounted to 17.9% of the acute reference dose of 300 µg/(kg bw·day) for women of childbearing age.

  1. Acute Decrease in HDL Cholesterol Associated With Exposure to Welding Fumes

    PubMed Central

    Rice, Mary Berlik; Cavallari, Jenn; Fang, Shona; Christiani, David

    2011-01-01

    Objective To investigate acute changes in circulating lipids after exposure to relatively high levels of particulate matter through welding. Methods Using a repeated measures panel study, lipid levels before and after welding and personal exposures to fine particulate matter (PM2.5) were measured in 36 male welders over 63 exposure and/or control days. Results There was a trend toward decrease in HDL (−2.3 mg/dL, P = 0.08) 18 hours after welding. This effect became significant (−2.6 mg/dL, P = 0.05) after adjustment for possible confounders. The effect was strongest (−4.3 mg/dL, P = 0.02) among welders who did not weld the day before the study. There were no significant changes in other lipids associated with welding or PM2.5 exposure. Conclusion Welding exposure was associated with an acute decrease in circulating HDL, which may relate to the inflammatory and proatherosclerotic effects of fine particle exposure. PMID:21187793

  2. Acute phase response, inflammation and metabolic syndrome biomarkers of Libby asbestos exposure

    SciTech Connect

    Shannahan, Jonathan H.; Alzate, Oscar; Winnik, Witold M.; Andrews, Debora; Schladweiler, Mette C.; Ghio, Andrew J.; Gavett, Stephen H.; Kodavanti, Urmila P.

    2012-04-15

    Identification of biomarkers assists in the diagnosis of disease and the assessment of health risks from environmental exposures. We hypothesized that rats exposed to Libby amphibole (LA) would present with a unique serum proteomic profile which could help elucidate epidemiologically-relevant biomarkers. In four experiments spanning varied protocols and temporality, healthy (Wistar Kyoto, WKY; and F344) and cardiovascular compromised (CVD) rat models (spontaneously hypertensive, SH; and SH heart failure, SHHF) were intratracheally instilled with saline (control) or LA. Serum biomarkers of cancer, inflammation, metabolic syndrome (MetS), and the acute phase response (APR) were analyzed. All rat strains exhibited acute increases in α-2-macroglobulin, and α1-acid glycoprotein. Among markers of inflammation, lipocalin-2 was induced in WKY, SH and SHHF and osteopontin only in WKY after LA exposure. While rat strain- and age-related changes were apparent in MetS biomarkers, no LA effects were evident. The cancer marker mesothelin was increased only slightly at 1 month in WKY in one of the studies. Quantitative Intact Proteomic profiling of WKY serum at 1 day or 4 weeks after 4 weekly LA instillations indicated no oxidative protein modifications, however APR proteins were significantly increased. Those included serine protease inhibitor, apolipoprotein E, α-2-HS-glycoprotein, t-kininogen 1 and 2, ceruloplasmin, vitamin D binding protein, serum amyloid P, and more 1 day after last LA exposure. All changes were reversible after a short recovery regardless of the acute or long-term exposures. Thus, LA exposure induces an APR and systemic inflammatory biomarkers that could have implications in systemic and pulmonary disease in individuals exposed to LA. -- Highlights: ► Biomarkers of asbestos exposure are required for disease diagnosis. ► Libby amphibole exposure is associated with increased human mortality. ► Libby amphibole increases circulating proteins involved

  3. Limited inflammatory response in rats after acute exposure to a silicon carbide nanoaerosol

    NASA Astrophysics Data System (ADS)

    Laloy, J.; Lozano, O.; Alpan, L.; Masereel, B.; Toussaint, O.; Dogné, J. M.; Lucas, S.

    2015-08-01

    Inhalation represents the major route of human exposure to manufactured nanomaterials (NMs). Assessments are needed about the potential risks of NMs from inhalation on different tissues and organs, especially the respiratory tract. The aim of this limited study is to determine the potential acute pulmonary toxicity in rats exposed to a dry nanoaerosol of silicon carbide (SiC) nanoparticles (NPs) in a whole-body exposure (WBE) model. The SiC nanoaerosol is composed of a bimodal size distribution of 92.8 and 480 nm. The exposure concentration was 4.91 mg/L, close to the highest recommended concentration of 5 mg/L by the Organisation for Economic Co-operation and Development. Rats were exposed for 6 h to a stable and reproducible SiC nanoaerosol under real-time measurement conditions. A control group was exposed to the filtered air used to create the nanoaerosol. Animals were sacrificed immediately, 24 or 72 h after exposure. The bronchoalveolar lavage fluid from rat lungs was recovered. Macrophages filled with SiC NPs were observed in the rat lungs. The greatest load of SiC and macrophages filled with SiC were observed on the rat lungs sacrificed 24 h after acute exposure. A limited acute inflammatory response was found up to 24 h after exposure characterized by a lactate dehydrogenase and total protein increase or presence of inflammatory cells in pulmonary lavage. For this study a WBE model has been developed, it allows the simultaneous exposure of six rats to a nanoaerosol and six rats to clean-filtered air. The nanoaerosol was generated using a rotating brush system (RBG-1000) and analyzed with an electrical low pressure impactor in real time.

  4. Short term respiratory effects of acute exposure to chlorine due to a swimming pool accident.

    PubMed

    Agabiti, N; Ancona, C; Forastiere, F; Di Napoli, A; Lo Presti, E; Corbo, G M; D'Orsi, F; Perucci, C A

    2001-06-01

    Acute exposure to chlorine causes lung damage, and recovery may proceed slowly for several weeks. The short term respiratory effects of acute chlorine inhalation during a swimming pool accident were examined. A total of 282 subjects (134 children, aged <14 years) inhaled hydrogen chloride and sodium hypochlorite during an accident caused by a malfunction of the water chlorinating system in a community pool in Rome in 1998. Most people received bronchodilators and cortisone at the emergency room; five children were admitted to hospital. A total of 260 subjects (92.2%) were interviewed about duration of exposure (<3, 3--5, >5 minutes), intensity of exposure (not at all or a little, a moderate amount, a lot), and respiratory symptoms. Lung function was measured in 184 people (82 children) after 15--30 days. The effects of exposure to chlorine were analysed through multiple linear regression, separately in adults and in children. Acute respiratory symptoms occurred among 66.7% of adults and 71.6% of children. The incidences were highest among those who had chronic respiratory disease and had a longer duration of exposure. In about 30% of the subjects, respiratory symptoms persisted for 15--30 days after the accident. Lung function levels were lower in those who reported a high intensity of exposure than in those who reported low exposure, both in children and in adults (mean (95% confidence interval (95% CI)) differences in forced expiratory volume in 1 second (FEV(1,)) were -109 (-310 to 93) ml, and -275 (-510 to -40) ml, respectively). Persistent symptoms and lung function impairment were found up to 1 month after the incident. Although community pool accidents happen rarely, the medical community needs to be alerted to the possible clinical and physiological sequelae, especially among susceptible people.

  5. Maintaining the Constant Exposure Condition for an Acute Caenorhabditis elegans Mortality Test Using Passive Dosing

    PubMed Central

    Kwon, Hyuck-Chul; Roh, Ji-Yeon; Lim, Dongyoung; Choi, Jinhee

    2011-01-01

    Objectives Maintaining the constant exposure to hydrophobic organic compouds in acute toxicity tests is one of the most difficult issues in the evaluation of their toxicity and corresponding risks. Passive dosing is an emerging tool to keep constant aqueous concentration because of the overwhelming mass loaded in the dosing phase. The primary objectives of this study were to develop the constant exposure condition for an acute mortality test and to compare the performance of the passive dosing method with the conventional spiking with co-solvent. Methods A custom cut polydimethylsiloxane (PDMS) tubing loaded with benzyl butyl phthalate (BBP) was placed in each well of a 24-well plate containing assay medium. The rate of the release of BBP from PDMS was evaluated by measuring the change in the concentration of BBP in the assay medium. The efficiency of maintaining constant exposure condition was also evaluated using a simple two-compartment mass transport model employing a film-diffusion theory. An acute mortality test using 10 C. elegans in each well was conducted for the evaluation of the validity of passive dosing and the comparative evaluation of the passive dosing method and the conventional spiking method. Results Free concentration in the assay medium reached 95% steady state value within 2.2 hours without test organisms, indicating that this passive dosing method is useful for an acute toxicity test in 24 hours. The measured concentration after the mortality test agreed well with the estimated values from partitioning between PDMS and the assay medium. However, the difference between the nominal and the free concentration became larger as the spiked concentration approached water solubility, indicating the instability of the conventional spiking with a co-solvent. Conclusions The results in this study support that passive dosing provides a stable exposure condition for an acute toxicity test. Thus, it is likely that more reliable toxicity assessment can be

  6. Radiation exposure to the orbiting lunar station and lunar surface related to reusable nuclear shuttle operations

    NASA Technical Reports Server (NTRS)

    Hutchinson, P. I.

    1972-01-01

    The radiation environment created by the Reusable Nuclear Vehicle (RNS) in performing its normal mission functions while in the lunar vicinity and the impact of that environment on the Orbiting Lunar Station (OLS) and/or the lunar surface are examined. Lunar surface exposures from the operating reactor were evaluated for both the arrival and departure burns and while there is little probability that manned bases would lie along the paths in which measurable exposures would be recorded, the analyses do indicate the need to consider this possibility in planning such operations. Conclusions supported by the analyses and recommended operational constraints for the RNS are presented.

  7. Trends in radiation exposure from clinical nuclear medicine procedures in Shanghai, China.

    PubMed

    Yi, Yanling; Zheng, Junzheng; Zhuo, Weihai; Gao, Linfeng

    2012-03-01

    This study was designed to assess the trends in the frequencies of nuclear medicine procedures in Shanghai, China, and to determine their contributions to the per capita effective dose to the Shanghai population. The mean activities of radionuclides administered by nuclear medicine departments were compared with the Chinese national guidelines on diagnostic reference levels. On the basis of the three surveys carried out by Shanghai Municipal Center for Disease Control and Prevention in 1996, 1998, and 2008, the typically administered radiopharmaceuticals, levels of activity, the number of procedures, and population were systematically analyzed to assess the frequencies of nuclear medicine procedures and the per capita effective dose. The frequencies were approximately 2.77, 3.46, and 6.63 per 1000 people in 1996, 1998, and 2008, respectively. The annual per capita doses from diagnostic nuclear medicine were estimated to be 0.016, 0.022, and 0.032 mSv in 1996, 1998, and 2008, respectively. The annual frequency of therapeutic nuclear medicine procedures increased from 0.131 to 0.430 per 1000 people in the intervening 12 years. In the 12 years before 2008, diagnostic and therapeutic procedures in nuclear medicine in Shanghai increased continuously, and the annual per capita dose doubled. Increases in PET imaging and bone scans were the major contributors to the increasing frequency and magnitude of radiation exposure to the population. The activities administered for most diagnostic procedures were generally consistent with the designated reference levels.

  8. Quantifying the effects of exposure to indoor air pollution from biomass combustion on acute respiratory infections in developing countries.

    PubMed Central

    Ezzati, M; Kammen, D M

    2001-01-01

    Acute respiratory infections (ARI) are the leading cause of burden of disease worldwide and have been causally linked with exposure to pollutants from domestic biomass fuels in developing countries. We used longitudinal health data coupled with detailed monitoring and estimation of personal exposure from more than 2 years of field measurements in rural Kenya to estimate the exposure-response relationship for particulates < 10 microm diameter (PM(10)) generated from biomass combustion. Acute respiratory infections and acute lower respiratory infections are concave, increasing functions of average daily exposure to PM(10), with the rate of increase declining for exposures above approximately 1,000-2,000 microg/m(3). This first estimation of the exposure-response relationship for the high-exposure levels characteristic of developing countries has immediate and important consequences for international public health policies, energy and combustion research, and technology transfer efforts that affect more than 2 billion people worldwide. PMID:11401759

  9. Cancer Events After Acute or Chronic Exposure to Sulfur Mustard: A Review of the Literature

    PubMed Central

    Razavi, Seyed Mansour; Abdollahi, Mohammad; Salamati, Payman

    2016-01-01

    Background: Sulfur mustard (SM) has been considered as a carcinogen in the laboratory studies. However, its carcinogenic effects on human beings were not well discussed. The main purpose of our study is to assess carcinogenesis of SM following acute and/or chronic exposures in human beings. Methods: The valid scientific English and Persian databases including PubMed, Web of Science, Scopus, IranMedex, and Irandoc were searched and the collected papers reviewed. The used keywords were in two languages: English and Persian. The inclusion criteria were the published original articles indexed in above-mentioned databases. Eleven full-texts out of 296 articles were found relevant and then assessed. Results: Studies on the workers of the SM factories during the World Wars showed that the long-term chronic exposure to mustards can cause a variety of cancers in the organs such as oral cavity, larynx, lung, and skin. Respiratory system was the most important affected system. Acute single exposure to SM was assumed as the carcinogenic inducer in the lung and blood and for few cancers including basal cell carcinoma and squamous cell carcinoma. Conclusions: SM is a proven carcinogen in chronic situations although data are not enough to strongly conclude in acute exposure. PMID:27280012

  10. Nuclear DNA as Predictor of Acute Kidney Injury in Patients Undergoing Coronary Artery Bypass Graft: A Pilot Study.

    PubMed

    Likhvantsev, Valery V; Landoni, Giovanni; Grebenchikov, Oleg A; Skripkin, Yuri V; Zabelina, Tatiana S; Zinovkina, Liudmila A; Prikhodko, Anastasia S; Lomivorotov, Vladimir V; Zinovkin, Roman A

    2017-05-01

    To measure the release of plasma nuclear deoxyribonucleic acid (DNA) and to assess the relationship between nuclear DNA level and acute kidney injury occurrence in patients undergoing cardiac surgery. Cardiovascular anesthesiology and intensive care unit of a large tertiary-care university hospital. Prospective observational study. Fifty adult patients undergoing cardiac surgery. Nuclear DNA concentration was measured in the plasma. The relationship between the level of nuclear DNA and the incidence of acute kidney injury after coronary artery bypass grafting was investigated. Cardiac surgery leads to significant increase in plasma nuclear DNA with peak levels 12 hours after surgery (median [interquartile range] 7.0 [9.6-22.5] µg/mL). No difference was observed between off-pump and on-pump surgical techniques. Nuclear DNA was the only predictor of acute kidney injury between baseline and early postoperative risk factors. The authors found an increase of nuclear DNA in the plasma of patients who had undergone coronary artery bypass grafting, with a peak after 12 hours and an association of nuclear DNA with postoperative acute kidney injury. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Indirect monitoring of internal exposure in the decommissioning of a nuclear power plant in Spain.

    PubMed

    Robredo, L M; Navarro, T; Sierra, I

    2000-01-01

    The experimental procedure used for the indirect measurement of internal exposure of workers involved in the first step of the decontamination of a nuclear power plant which is being decommissioned is presented. The establishment of decontamination and decommissioning programs is currently in progress at the nuclear power plant and monitoring procedures to assess workers' exposure have also been implemented. Due to the presence of transuranics, the monitoring program includes the analysis of excreta samples. An analytical method for the determination of plutonium (Pu) and americum (Am) in urine samples was developed. The radiochemical separation is based on the coprecipitation of transuranics and sequential isolation of Pu and Am by anion exchange and extraction chromatography. Finally, electrodeposited sources are prepared and counted by alpha-spectrometry.

  12. Acute illnesses among Los Angeles County lifeguards according to worksite exposures.

    PubMed Central

    Sullivan, C S; Barron, M E

    1989-01-01

    Due to public concern regarding the potential adverse health effects of exposure to Santa Monica Bay waters, a case-control study of acute illnesses among Los Angeles County lifeguards was conducted. Workers' compensation claimants (N = 112) were matched to healthy lifeguards working in the same year and having the same job classification. Conditional logistic regression showed that the southernmost worksites of the bay were associated with all acute illnesses (OR = 14.4, 95% CI = 4.7, 44.8) and with ear infections (OR = 12.5, 95% CI = 2.9, 53.4). PMID:2817175

  13. A task-based assessment of parental occupational exposure to pesticides and childhood acute lymphoblastic leukemia.

    PubMed

    Gunier, Robert B; Kang, Alice; Hammond, S Katharine; Reinier, Kyndaron; Lea, C Suzanne; Chang, Jeffrey S; Does, Monique; Scelo, Ghislaine; Kirsch, Janice; Crouse, Vonda; Cooper, Robert; Quinlan, Patricia; Metayer, Catherine

    2017-07-01

    Associations between parental occupational pesticide exposure and childhood acute lymphoblastic leukemia (ALL) vary across studies, likely due to different exposure assessment methodologies. We assessed parental occupational pesticide exposure from the year before pregnancy to the child's third year of life for 669 children diagnosed with ALL and 1021 controls. We conducted expert rating using task-based job modules (JM) to estimate exposure to pesticides among farmer workers, gardeners, agricultural packers, and pesticide applicators. We compared this method to (1) partial JM using job titles and a brief description, but without completing the task-based questionnaire, and (2) job exposure matrix (JEM) linking job titles to the International Standard Classifications of Occupation Codes. We used unconditional logistic regression to calculate odds ratios (OR) and 95% confidence intervals (95% CI) for ALL cancer risk and pesticide exposure adjusting for child's sex, age, race/ethnicity and household income. Compared to complete JMs, partial JMs and JEM led to 3.1% and 9.4% of parents with pesticide exposure misclassified, respectively. Misclassification was similar in cases and controls. Using complete JMs, we observed an increased risk of ALL for paternal occupational exposure to any pesticides (OR=1.7; 95% CI=1.2, 2.5), with higher risks reported for pesticides to treat nut crops (OR=4.5; 95% CI=0.9, 23.0), and for children diagnosed before five years of age (OR=2.3; 95% CI: 1.3, 4.1). Exposure misclassification from JEM attenuated these associations by about 57%. Maternal occupational pesticide exposure before and after birth was not associated with ALL. The risk of ALL was elevated in young children with paternal occupational pesticide exposure during the perinatal period, using more detailed occupational information for exposure classification. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Mortality associated with chronic external radiation exposure in the French combined cohort of nuclear workers.

    PubMed

    Metz-Flamant, C; Laurent, O; Samson, E; Caër-Lorho, S; Acker, A; Hubert, D; Richardson, D B; Laurier, D

    2013-09-01

    The long-term effects of protracted low level ionising radiation exposure are investigated in a combined analysis of French nuclear workers employed by the Commissariat à l'Energie Atomique (CEA), AREVA Nuclear Cycle (AREVA NC) and Electricité de France (EDF). Associations between cumulative external radiation dose and mortality due to solid cancers, leukaemia and circulatory disease were examined. All workers hired by CEA, AREVA NC and EDF between 1950 and 1994 who were employed for at least 1 year, badge-monitored for radiation exposure and alive on 1 January 1968 were included. Individual data of annual exposure to penetrating photons (X-rays and gamma rays) were reconstructed for each worker. Estimates of radiation dose-mortality associations were obtained using a linear excess relative risk (ERR) Poisson regression model. Among the 59 021 nuclear workers, 2312 died of solid cancer, 78 of leukaemia and 1468 of circulatory diseases during the 1968-2004 period. Approximately 72% of the cohort had a non-zero cumulative radiation dose estimate, with a mean cumulative dose of 22.5 mSv. Positive but non-significant ERR/Sv were observed for all solid cancers, leukaemia excluding chronic lymphocytic leukaemia (CLL), ischaemic heart diseases and cerebrovascular diseases. A significant ERR/Sv was found for myeloid leukaemia. This is the first combined analysis of major French cohorts of nuclear workers. Results were consistent with risks estimated in other nuclear worker cohorts and illustrate the potential of a further joint international study to yield direct risk estimates in support to radiation protection standards.

  15. Characterisation of cochlear inflammation in mice following acute and chronic noise exposure.

    PubMed

    Tan, Winston J T; Thorne, Peter R; Vlajkovic, Srdjan M

    2016-08-01

    Oxidative stress has been established as the key mechanism of the cochlear damage underlying noise-induced hearing loss, however, emerging evidence suggests that cochlear inflammation may also be a major contributor. This study aimed to improve our understanding of the cochlear inflammatory response associated with acute and chronic noise exposure. C57BL/6 mice were exposed to acute traumatic noise (100 dBSPL, 8-16 kHz for 24 h) and their cochleae collected at various intervals thereafter, up to 7 days. Using quantitative RT-PCR and immunohistochemistry, changes in expression levels of proinflammatory cytokines (TNF-α, IL-1β), chemokines (CCL2) and cell adhesion molecules (ICAM-1) were studied. All gene transcripts displayed similar dynamics of expression, with an early upregulation at 6 h post-exposure, followed by a second peak at 7 days. ICAM-1 immunoexpression increased significantly in the inferior region of the spiral ligament, peaking 24 h post-exposure. The early expression of proinflammatory mediators likely mediates the recruitment and extravasation of inflammatory cells into the noise-exposed cochlea. The occurrence of the latter expression peak is not clear, but it may be associated with reparative processes initiated in response to cochlear damage. Chronic exposure to moderate noise (90 dBSPL, 8-16 kHz, 2 h/day, up to 4 weeks) also elicited an inflammatory response, reaching a maximum after 2 weeks, suggesting that cochlear damage and hearing loss associated with chronic environmental noise exposure may be linked to inflammatory processes in the cochlea. This study thus provides further insight into the dynamics of the cochlear inflammatory response induced by exposure to acute and chronic noise.

  16. Cutaneous exposure to vesicant phosgene oxime: Acute effects on the skin and systemic toxicity.

    PubMed

    Tewari-Singh, Neera; Goswami, Dinesh G; Kant, Rama; Croutch, Claire R; Casillas, Robert P; Orlicky, David J; Agarwal, Rajesh

    2017-02-15

    Phosgene Oxime (CX), an urticant or nettle agent categorized as a vesicant, is a potential chemical warfare and terrorist weapon. Its exposure can result in widespread and devastating effects including high mortality due to its fast penetration and ability to cause immediate severe cutaneous injury. It is one of the least studied chemical warfare agents with no effective therapy available. Thus, our goal was to examine the acute effects of CX following its cutaneous exposure in SKH-1 hairless mice to help establish a relevant injury model. Results from our study show that topical cutaneous exposure to CX vapor causes blanching of exposed skin with an erythematous ring, necrosis, edema, mild urticaria and erythema within minutes after exposure out to 8h post-exposure. These clinical skin manifestations were accompanied with increases in skin thickness, apoptotic cell death, mast cell degranulation, myeloperoxidase activity indicating neutrophil infiltration, p53 phosphorylation and accumulation, and an increase in COX-2 and TNFα levels. Topical CX-exposure also resulted in the dilatation of the peripheral vessels with a robust increase in RBCs in vessels of the liver, spleen, kidney, lungs and heart tissues. These events could cause a drop in blood pressure leading to shock, hypoxia and death. Together, this is the first report on effects of CX cutaneous exposure, which could help design further comprehensive studies evaluating the acute and chronic skin injuries from CX topical exposure and elucidate the related mechanism of action to aid in the identification of therapeutic targets and mitigation of injury. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Tadpole swimming performance and activity affected by acute exposure to sublethal levels of carbaryl

    USGS Publications Warehouse

    Bridges, C.M.

    1997-01-01

    General activity and swimming performance (i.e., sprint speed and distance) of plains leopard frog tadpoles (Rana blairi) were examined after acute exposure to three sublethal concentrations of carbaryl (3.5, 5.0, and 7.2 mg/L). Both swimming performance and spontaneous swimming activity are important for carrying out life history functions (e.g., growth and development) and for escaping from predators. Measured tadpole activity diminished by nearly 90% at 3.5 mg/L carbaryl and completely ceased at 7.2 mg/L. Sprint speed and sprint distance also decreased significantly following exposure. Carbaryl affected both swimming performance and activity after just 24 h, suggesting that 24 h may be an adequate length of exposure to determine behavioral effects on tadpoles. Slight recovery of activity levels was noted at 24 and 48 h post-exposure; no recovery of swimming performance was observed. Reduction in activity and swimming performance may result in increased predation rates and, because activity is closely associated with feeding, may result in slowed growth leading to a failure to emerge before pond drying or an indirect reduction in adult fitness. Acute exposure to sublethal toxicants such as carbaryl may not only affect immediate survival of tadpoles but also impact critical life history functions and generate changes at the local population level.

  18. Acute exposure to 2,4-dinitrophenol alters zebrafish swimming performance and whole body triglyceride levels.

    PubMed

    Marit, Jordan S; Weber, Lynn P

    2011-06-01

    While swimming endurance (critical swimming speed or U(crit)) and lipid stores have both been reported to acutely decrease after exposure to a variety of toxicants, the relationship between these endpoints has not been clearly established. In order to examine these relationships, adult zebrafish (Danio rerio) were aqueously exposed to solvent control (ethanol) or two nominal concentrations of 2,4-dinitrophenol (DNP), a mitochondrial electron transport chain uncoupler, for a 24-h period. Following exposure, fish were placed in a swim tunnel in clean water for swimming testing or euthanized immediately without testing, followed by analysis of whole body triglyceride levels. U(crit) decreased in both the 6 mg/L and 12 mg/L DNP groups, with 12 mg/L approaching the LC₅₀. A decrease in tail beat frequency was observed without a significant change in tail beat amplitude. In contrast, triglyceride levels were elevated in a concentration-dependent manner in the DNP exposure groups, but only in fish subjected to swimming tests. This increase in triglyceride stores may be due to a direct interference of DNP on lipid catabolism as well as increased triglyceride production when zebrafish were subjected to the co-stressors of swimming and toxicant exposure. Future studies should be directed at determining how acute DNP exposure combines with swimming to cause alterations in triglyceride accumulation.

  19. Suppression of antibody response in mice by acute exposure to nitrogen dioxide: in vitro study

    SciTech Connect

    Hidekazu, F.; Shimizu, F.; Kubota, K.

    1981-12-01

    The effect of acute exposure to nitrogen dioxide (NO/sub 2/) on in vitro primary and secondary antibody responses to sheep red blood cells (SRBC) was studied in BALB/c mice. After the in vivo exposure to 20 ppm NO/sub 2/ for 12 hr, spleen cells were separated and then cultured with SRBC. Cell reconstitution experiments indicated that in the primary antibody response B cells were more strongly suppressed than T cells, while in the secondary response suppression of primed T cells was greater than that of prime B cells.

  20. Radiological protection from radioactive waste management in existing exposure situations resulting from a nuclear accident.

    PubMed

    Sugiyama, Daisuke; Hattori, Takatoshi

    2013-01-01

    In environmental remediation after nuclear accidents, radioactive wastes have to be appropriately managed in existing exposure situations with contamination resulting from the emission of radionuclides by such accidents. In this paper, a framework of radiation protection from radioactive waste management in existing exposure situations for application to the practical and reasonable waste management in contaminated areas, referring to related ICRP recommendations was proposed. In the proposed concept, intermediate reference levels for waste management are adopted gradually according to the progress of the reduction in the existing ambient dose in the environment on the basis of the principles of justification and optimisation by taking into account the practicability of the management of radioactive waste and environmental remediation. It is essential to include the participation of relevant stakeholders living in existing exposure situations in the selection of reference levels for the existing ambient dose and waste management.

  1. Occupational Radiation Exposure at Commercial Nuclear Power Reactors and Other Facilities 2008

    SciTech Connect

    U.S. Nuclear Regulatory Commission, Office of Nuclear Regulatory Research

    2009-12-01

    This report summarizes the occupational exposure data that are maintained in the U.S. Nuclear Regulatory Commission (NRC) Radiation Exposure Information and Reporting System (REIRS). The bulk of the information contained in the report was compiled from the 2008 annual reports submitted by five of the seven categories1 of NRC licensees subject to the reporting requirements of 10 CFR 20.2206. The annual reports submitted by these licensees consist of radiation exposure records for each monitored individual. These records are analyzed for trends and presented in this report in terms of collective dose and the distribution of dose among the monitored individuals. Because there are no geologic repositories for high-level waste currently licensed and no low-level waste disposal facilities in operation, only five categories will be considered in this report.

  2. Radiological protection from radioactive waste management in existing exposure situations resulting from a nuclear accident

    PubMed Central

    Sugiyama, Daisuke; Hattori, Takatoshi

    2013-01-01

    In environmental remediation after nuclear accidents, radioactive wastes have to be appropriately managed in existing exposure situations with contamination resulting from the emission of radionuclides by such accidents. In this paper, a framework of radiation protection from radioactive waste management in existing exposure situations for application to the practical and reasonable waste management in contaminated areas, referring to related ICRP recommendations was proposed. In the proposed concept, intermediate reference levels for waste management are adopted gradually according to the progress of the reduction in the existing ambient dose in the environment on the basis of the principles of justification and optimisation by taking into account the practicability of the management of radioactive waste and environmental remediation. It is essential to include the participation of relevant stakeholders living in existing exposure situations in the selection of reference levels for the existing ambient dose and waste management. PMID:22719047

  3. Acute and chronic toxicity of sodium sulfate to four freshwater organisms in water-only exposures

    USGS Publications Warehouse

    Wang, Ning; Consbrock, Rebecca A.; Ingersoll, Christopher G.; Hardesty, Douglas K.; Brumbaugh, William G.; Hammer, Edward J.; Bauer, Candice R.; Mount, David R.

    2016-01-01

    The acute and chronic toxicity of sulfate (tested as sodium sulfate) was determined in diluted well water (hardness of 100 mg/L and pH 8.2) with a cladoceran (Ceriodaphnia dubia; 2-d and 7-d exposures), a midge (Chironomus dilutus; 4-d and 41-d exposures), a unionid mussel (pink mucket, Lampsilis abrupta; 4-d and 28-d exposures), and a fish (fathead minnow, Pimephales promelas; 4-d and 34-d exposures). Among the 4 species, the cladoceran and mussel were acutely more sensitive to sulfate than the midge and fathead minnow, whereas the fathead minnow was chronically more sensitive than the other 3 species. Acute-to-chronic ratios ranged from 2.34 to 5.68 for the 3 invertebrates but were as high as 12.69 for the fish. The fathead minnow was highly sensitive to sulfate during the transitional period from embryo development to hatching in the diluted well water, and thus, additional short-term (7- to 14-d) sulfate toxicity tests were conducted starting with embryonic fathead minnow in test waters with different ionic compositions at a water hardness of 100 mg/L. Increasing chloride in test water from 10 mg Cl/L to 25 mg Cl/L did not influence sulfate toxicity to the fish, whereas increasing potassium in test water from 1mg K/L to 3mg K/L substantially reduced the toxicity of sulfate. The results indicate that both acute and chronic sulfate toxicity data, and the influence of potassium on sulfate toxicity to fish embryos, need to be considered when environmental guidance values for sulfate are developed or refined.

  4. Micro RNA responses to chronic or acute exposures to low dose ionizing radiation

    PubMed Central

    Chaudhry, M. Ahmad; Omaruddin, Romaica A.; Kreger, Bridget; de Toledo, Sonia M.; Azzam, Edouard I.

    2014-01-01

    Human health risks of exposure to low dose ionizing radiation remain ambiguous and are the subject of intense debate. A wide variety of biological effects are induced after cellular exposure to ionizing radiation, but the underlying molecular mechanism(s) remain to be completely understood. We hypothesized that low dose c-radiation-induced effects are controlled by the modulation of micro RNA (miRNA) that participate in the control of gene expression at the posttranscriptional level and are involved in many cellular processes. We monitored the expression of several miRNA in human cells exposed to acute or chronic low doses of 10 cGy or a moderate dose of 400 cGy of 137Cs γ-rays. Dose, dose rate and time dependent differences in the relative expression of several miRNA were investigated. The expression patterns of many miRNA differed after exposure to either chronic or acute 10 cGy. The expression of miRNA let-7e, a negative regulator of RAS oncogene, and the c-MYC miRNA cluster were upregulated after 10 cGy chronic dose but were downregulated after 3 h of acute 10 cGy. The miR-21 was upregulated in chronic or acute low dose and moderate dose treated cells and its target genes hPDCD4, hPTEN, hSPRY2, and hTPM1 were found to be downregulated. These findings provide evidence that low dose and dose rate c-irradiation dictate the modulation of miRNA, which can result in a differential cellular response than occurs at high doses. This information will contribute to understanding the risks to human health after exposure to low dose radiation. PMID:22367372

  5. Acute and chronic toxicity of sodium sulfate to four freshwater organisms in water-only exposures.

    PubMed

    Wang, Ning; Dorman, Rebecca A; Ingersoll, Christopher G; Hardesty, Doug K; Brumbaugh, William G; Hammer, Edward J; Bauer, Candice R; Mount, David R

    2016-01-01

    The acute and chronic toxicity of sulfate (tested as sodium sulfate) was determined in diluted well water (hardness of 100 mg/L and pH 8.2) with a cladoceran (Ceriodaphnia dubia; 2-d and 7-d exposures), a midge (Chironomus dilutus; 4-d and 41-d exposures), a unionid mussel (pink mucket, Lampsilis abrupta; 4-d and 28-d exposures), and a fish (fathead minnow, Pimephales promelas; 4-d and 34-d exposures). Among the 4 species, the cladoceran and mussel were acutely more sensitive to sulfate than the midge and fathead minnow, whereas the fathead minnow was chronically more sensitive than the other 3 species. Acute-to-chronic ratios ranged from 2.34 to 5.68 for the 3 invertebrates but were as high as 12.69 for the fish. The fathead minnow was highly sensitive to sulfate during the transitional period from embryo development to hatching in the diluted well water, and thus, additional short-term (7- to 14-d) sulfate toxicity tests were conducted starting with embryonic fathead minnow in test waters with different ionic compositions at a water hardness of 100 mg/L. Increasing chloride in test water from 10 mg Cl/L to 25 mg Cl/L did not influence sulfate toxicity to the fish, whereas increasing potassium in test water from 1 mg K/L to 3 mg K/L substantially reduced the toxicity of sulfate. The results indicate that both acute and chronic sulfate toxicity data, and the influence of potassium on sulfate toxicity to fish embryos, need to be considered when environmental guidance values for sulfate are developed or refined.

  6. Pathogenesis of Acute and Delayed Corneal Lesions after Ocular Exposure to Sulfur Mustard Vapor

    DTIC Science & Technology

    2012-01-01

    2000) Nanoscale topography of the basement membrane underlying the corneal epithelium of the rhesus macaque. Cell Tissue Res 299: 39–46. 28. Pal-Ghosh...DATES COVERED (From - To) 4. TITLE AND SUBTITLE Pathogenesis of acute and delayed corneal lesions after ocular exposure to 5a. CONTRACT NUMBER sulfur...involves a progressive corneal degeneration resulting in chronic ocular discomfort and impaired vision for which clinical interventions have typically

  7. Acute respiratory effects and endotoxin exposure during wheat harvest in Northeastern Colorado.

    PubMed

    Viet, S M; Buchan, R; Stallones, L

    2001-06-01

    Acute cross-shift respiratory changes were evaluated for workers at 25 farms in northeastern Colorado during the summer of 1994 wheat harvest. Information on workers' respiratory health, past occupational exposures, and smoking status was obtained. Each worker was asked to rank eight acute symptoms before he or she began harvest work for the day. Spirometry was also performed before work began. Each participant wore a high-flow personal air sampling pump for the full shift. At the end of the workshift, spirometry and ranking of the eight acute symptoms were conducted again. Total dust exposure was determined gravimetrically. Total endotoxin was measured by the Limulus amoebocyte lysate (LAL) assay. The 98 harvest workers included in the study ranged in age from 18 to 80. Ten percent of the workers had moderate airway obstruction, as indicated by the pre-shift spirometry test results. Fifty percent of the workers were current or ex-smokers. Despite an unusually poor harvest, total dust exposures ranged from 0.09 to 15.33 mg/m3 (geometric mean 0.83 mg/m3), with 8 percent of workers exposed above the American Conference of Government Industrial Hygienists (ACGIH) threshold limit value (TLV) of 4 mg/m3. Total endotoxin exposures ranged from 4.4 to 744.4 EU/m3 (geometric mean 54.2 EU/m3), with 33 percent of workers exposed above 90 EU/m3, the level suggested as a threshold for acute mucous membrane irritation and pulmonary change among cotton workers. Sixty percent of workers experienced a cross-shift change in at least one respiratory symptom. The respiratory index (sum of cross-shift changes in the eight acute respiratory symptoms) was significantly correlated with both total dust and endotoxin exposure. Cross-shift changes in the spirometric variables were associated with smoking status, age, presence of airway obstruction, and history of chronic respiratory symptoms, but not with dust or endotoxin exposure. Peak expiratory flow rate was found to decrease over the

  8. Cold exposure rapidly induces virtual saturation of brown adipose tissue nuclear T sub 3 receptors

    SciTech Connect

    Bianco, A.C.; Silva, J.E. Harvard Medical School, Boston, MA )

    1988-10-01

    Cold exposure induces a rapid increase in uncoupling protein (UCP) concentration in the brown adipose tissue (BAT) of euthyroid, but not hypothyroid, rats. To normalize this response with exogenous 3,5,3{prime}-triiodothyronine (T{sub 3}), it is necessary to cause systemic hyperthyroidism. In contrast, the same result can be obtained with just replacement doses of thyroxine (T{sub 4}) and, in euthyroid rats, the normal response of UCP to cold occurs without hyperthyroid plasma T{sub 3} levels. Consequently, the authors explored the possibility that the cold-induced activation of the type II 5{prime}-deiodinase resulted in high levels of nuclear T{sub 3} receptor occupancy in euthyroid rats. Studies were performed with pulse injections of tracer T{sub 3} or T{sub 4} in rats exposed to 4{degree}C for different lengths of time (1 h-3 wk). Within 4 h of cold exposure, they observed a significant increase in the nuclear ({sup 125}I)T{sub 3} derived from the tracer ({sup 125}I)T{sub 4} injections (T{sub 3}(T{sub 4})) and a significant reduction in the nuclear ({sup 125}I)T{sub 3} derived from ({sup 125}I)T{sub 3} injections (T{sub 3}(T{sub 3})). The number of BAT nuclear T{sub 3} receptors did not increase for up to 3 wk of observation at 4{degree}C. The mass of nuclear-bound T{sub 3} was calculated from the nuclear tracer ({sup 125}I)T{sub 3}(T{sub 3}) and ({sup 125}I)T{sub 3}(T{sub 4}) at equilibrium and the specific activity of serum T{sub 3} and T{sub 4}, respectively. By 4 h after the initiation of the cold exposure, the receptors were >95% occupied and remained so for the 3 weeks of observation. They conclude that the simultaneous activation of the deiodinase with adrenergic BAT stimulation serves the purpose of nearly saturating the nuclear T{sub 3} receptors. This makes possible the realization of the full thermogenic potential of the tissue without causing systemic hyperthyroidism.

  9. [Myocardial ultrastructural changes in rats following different levels of acute +Gz exposure].

    PubMed

    Zheng, Jun; Liu, Cheng-gang; Ren, Li; Xiao, Xiao-guang; Xu, Shu-xuan; Wang, Ping; Ji, Gui-ying

    2004-06-01

    To observe the effects of different levels of acute +Gz exposure on myocardial ultrastructure of rats and provide experimental basis for further development of anti-G measures. Twenty male Wistar rats were randomly divided into 4 groups (n=5): normal control group, +20 Gz group, +10 Gz group and +5 Gz group. Profile of the centrifuge +Gz exposure was trapezoidal, in which +20 Gz lasted for 30 s, +10 Gz for 1.5 min. +5 Gz exposure was repeated for 3 times with 30 min interval and each for 1.5 min. Myocardial tissue of left ventricle was sampled for transmission electron microscopy 5 h after exposure. +20 Gz and +10 Gz exposure caused obvious edema of myocardial and endothelial cells, myofibril disorder and injuries of mitochondria and nucleus. Breaks of myocardial fiber, formation of contraction bands and rupture of mitochondria were also observed in +20 Gz group. In +5 Gz group, there was still slight edema of myocardial and endothelial cells, while organic changes of myocardial ultrastructure were not observed. High +Gz exposure can cause myocardial ultrastructural injury in rats. Slight reversible injured response can also be observed in myocardial cell after repeated moderate level of +Gz exposure. This indicates that attention should be paid to the study of the effect of high +Gz on heart in pilots.

  10. Risk of childhood acute lymphoblastic leukaemia following parental occupational exposure to extremely low frequency electromagnetic fields

    PubMed Central

    Reid, A; Glass, D C; Bailey, H D; Milne, E; de Klerk, N H; Downie, P; Fritschi, L

    2011-01-01

    Background: Earlier studies have reported moderate increases in the risk of acute lymphoblastic leukaemia (ALL) among children whose mothers have been occupationally exposed to extremely low frequency (ELF) electromagnetic fields. Other studies examining parental occupational exposure to ELF and ALL have reported mixed results. Methods: In an Australian case–control study of ALL in children aged <15 years, parents were asked about tasks they undertook in each job. Exposure variables were created for any occupational exposure before the birth of the child, in jobs 2 years before birth, in jobs 1 year before birth and up to 1 year after birth. Results: In all, 379 case and 854 control mothers and 328 case and 748 control fathers completed an occupational history. Exposure to ELF in all time periods was similar in case and control mothers. There was no difference in exposure between case and control fathers. There was no association between maternal (odds ratio (OR)=0.96; 95% CI=0.74–1.25) or paternal (OR=0.78; 95% CI=0.56–1.09) exposure to ELF any time before the birth and risk of childhood ALL. Conclusion: We did not find an increased risk of ALL in offspring of parents with occupational exposure to ELF. PMID:21915123

  11. Risk of childhood acute lymphoblastic leukaemia following parental occupational exposure to extremely low frequency electromagnetic fields.

    PubMed

    Reid, A; Glass, D C; Bailey, H D; Milne, E; de Klerk, N H; Downie, P; Fritschi, L

    2011-10-25

    Earlier studies have reported moderate increases in the risk of acute lymphoblastic leukaemia (ALL) among children whose mothers have been occupationally exposed to extremely low frequency (ELF) electromagnetic fields. Other studies examining parental occupational exposure to ELF and ALL have reported mixed results. In an Australian case-control study of ALL in children aged < 15 years, parents were asked about tasks they undertook in each job. Exposure variables were created for any occupational exposure before the birth of the child, in jobs 2 years before birth, in jobs 1 year before birth and up to 1 year after birth. In all, 379 case and 854 control mothers and 328 case and 748 control fathers completed an occupational history. Exposure to ELF in all time periods was similar in case and control mothers. There was no difference in exposure between case and control fathers. There was no association between maternal (odds ratio (OR)=0.96; 95% CI=0.74-1.25) or paternal (OR=0.78; 95% CI=0.56-1.09) exposure to ELF any time before the birth and risk of childhood ALL. We did not find an increased risk of ALL in offspring of parents with occupational exposure to ELF.

  12. Parental exposure to carcinogens and risk for childhood acute lymphoblastic leukemia, Colombia, 2000-2005.

    PubMed

    Castro-Jiménez, Miguel Ángel; Orozco-Vargas, Luis Carlos

    2011-09-01

    The objective of this study was to determine the risk factors for childhood acute lymphoblastic leukemia (ALL) and, in particular, the role of parental occupational exposure to carcinogenic and probably carcinogenic hydrocarbons before the child's conception. For this case-control study, cases were children younger than 15 years who were newly diagnosed with ALL between January 2000 and March 2005 at 1 of 6 Colombian hospitals. An interview with both parents of 170 children (85 cases and 85 individually matched neighborhood controls) gathered information about each child's exposures and parental demographic and occupational characteristics, medical history, health risk behaviors, and pregnancy and birth history. A job-exposure matrix was used to classify parental exposure to hydrocarbons on the basis of the main industrial activity of each workplace where parents worked before (both parents) or during the index pregnancy (mother only). Conditional odds ratios and 95% confidence intervals were calculated by period of exposure (preconception, pregnancy, and childhood). The risk of childhood ALL was linked to 1) parental occupational exposure to hydrocarbons before conception, 2) parental smoking before conception, 3) maternal low socioeconomic status during pregnancy, and 4) higher maternal age (≥35 y) at the child's birth. These findings suggest an association between childhood ALL and parental occupational exposure to carcinogenic and probably carcinogenic hydrocarbons before conception. Outcomes depended on the parent exposed. Future research should investigate the additive or multiplicative role of other environmental sources of hydrocarbons.

  13. Rainbow trout (Oncorhynchus mykiss) pro-oxidant and genotoxic responses following acute and chronic exposure to the antibiotic oxytetracycline.

    PubMed

    Rodrigues, Sara; Antunes, Sara C; Correia, Alberto T; Nunes, Bruno

    2017-01-01

    Oxytetracycline (OTC), an antibacterial agent, is extensively used in aquaculture practices all over the world, but also in human and veterinary medicines. Because of its intensive use, low rates of absorption by treated animals, inadequate disposal, and low efficiency of removal in wastewater treatment plants, the potential harmful effects on aquatic organisms are of great concern. This work aimed to assess the effects of this antibiotic in rainbow trout, following both acute and chronic exposures. Catalase (CAT), total glutathione peroxidase (GPx), glutathione reductase (GRed) activities and lipid peroxidation (TBARS levels) were quantified as oxidative stress biomarkers, in gills and liver. Genotoxic endpoints, reflecting different types of genetic damage in blood cells, were also determined, by analysis of genetic damage (determination of the genetic damage index, GDI, measured by comet assay) and erythrocytic nuclear abnormalities (ENAs). The obtained results showed a mild pattern of antioxidant response, with modifications in CAT and GPx activities in gills, and lipid peroxidation in liver. These results suggest that despite the occurrence of oxidative effects, a full scenario of oxidative stress is not likely. However, exposure to OTC resulted in the establishment of genotoxic alterations with the induction of DNA strand breaks in blood cells (increase of GDI), and of chromosome breakage and/or segregational abnormalities (increase of ENAs). Considering that the oxidative response was not totally devisable, other mechanisms may be involved in the genotoxic effects reported.

  14. Stress sensitizes the brain: increased processing of unpleasant pictures after exposure to acute stress.

    PubMed

    Weymar, Mathias; Schwabe, Lars; Löw, Andreas; Hamm, Alfons O

    2012-07-01

    A key component of acute stress is a surge in vigilance that enables a prioritized processing of highly salient information to promote the organism's survival. In this study, we investigated the neural effects of acute stress on emotional picture processing. ERPs were measured during a deep encoding task, in which 40 male participants categorized 50 unpleasant and 50 neutral pictures according to arousal and valence. Before picture encoding, participants were subjected either to the Socially Evaluated Cold Pressor Test (SECPT) or to a warm water control procedure. The exposure to the SECPT resulted in increased subjective and autonomic (heart rate and blood pressure) stress responses relative to the control condition. Viewing of unpleasant relative to neutral pictures evoked enhanced late positive potentials (LPPs) over centro-parietal scalp sites around 400 msec after picture onset. Prior exposure to acute stress selectively increased the LPPs for unpleasant pictures. Moreover, the LPP magnitude for unpleasant pictures following the SECPT was positively associated with incidental free recall performance 24 hr later. The present results suggest that acute stress sensitizes the brain for increased processing of cues in the environment, particularly priming the processing of unpleasant cues. This increased processing is related to later long-term memory performance.

  15. Exposure to acute stress enhances decision-making competence: Evidence for the role of DHEA.

    PubMed

    Shields, Grant S; Lam, Jovian C W; Trainor, Brian C; Yonelinas, Andrew P

    2016-05-01

    Exposure to acute stress can impact performance on numerous cognitive abilities, but little is known about how acute stress affects real-world decision-making ability. In the present study, we induced acute stress with a standard laboratory task involving uncontrollable socio-evaluative stress and subsequently assessed decision-making ability using the Adult Decision Making Competence index. In addition, we took baseline and post-test saliva samples from participants to examine associations between decision-making competence and adrenal hormones. Participants in the stress induction group showed enhanced decision-making competence, relative to controls. Further, although both cortisol and dehydroepiandrosterone (DHEA) reactivity predicted decision-making competence when considered in isolation, DHEA was a significantly better predictor than cortisol when both hormones were considered simultaneously. Thus, our results show that exposure to acute stress can have beneficial effects on the cognitive ability underpinning real-world decision-making and that this effect relates to DHEA reactivity more than cortisol.

  16. Exposure to Acute Stress Enhances Decision-Making Competence: Evidence for the Role of DHEA

    PubMed Central

    Shields, Grant S.; Lam, Jovian C. W.; Trainor, Brian C.; Yonelinas, Andrew P.

    2016-01-01

    Exposure to acute stress can impact performance on numerous cognitive abilities, but little is known about how acute stress affects real-world decision-making ability. In the present study, we induced acute stress with a standard laboratory task involving uncontrollable socio-evaluative stress and subsequently assessed decision-making ability using the Adult Decision Making Competence index. In addition, we took baseline and post-test saliva samples from participants to examine associations between decision-making competence and adrenal hormones. Participants in the stress induction group showed enhanced decision-making competence, relative to controls. Further, although both cortisol and dehydroepiandrosterone (DHEA) reactivity predicted decision-making competence when considered in isolation, DHEA was a significantly better predictor than cortisol when both hormones were considered simultaneously. Thus, our results show that exposure to acute stress can have beneficial effects on the cognitive ability underpinning real-world decision-making and that this effect relates to DHEA reactivity more than cortisol. PMID:26874561

  17. Characterization of exposure-dependent eigenvalue drift using Monte Carlo based nuclear fuel management

    NASA Astrophysics Data System (ADS)

    Xoubi, Ned

    2005-12-01

    The ability to accurately predict the multiplication factor (keff) of a nuclear reactor core as a function of exposure continues to be an elusive task for core designers despite decades of advances in computational methods. The difference between a predicted eigenvalue (target) and the actual eigenvalue at critical reactor conditions is herein referred to as the "eigenvalue drift." This dissertation studies exposure-dependent eigenvalue drift using MCNP-based fuel management analysis of the ORNL High Flux Isotope Reactor core. Spatial-dependent burnup is evaluated using the MONTEBURNS and ALEPH codes to link MCNP to ORIGEN to help analyze the behavior of keff as a function of fuel exposure. Understanding the exposure-dependent eigenvalue drift of a nuclear reactor is of particular relevance when trying to predict the impact of major design changes upon fuel cycle behavior and length. In this research, the design of an advanced HFIR core with a fuel loading of 12 kg of 235U is contrasted against the current loading of 9.4 kg. The goal of applying exposure dependent eigenvalue characterization is to produce a more accurate prediction of the fuel cycle length than prior analysis techniques, and to improve our understanding of the reactivity behavior of the core throughout the cycle. This investigation predicted a fuel cycle length of 40 days, representing a 50% increase in the cycle length in response to a 25% increase in fuel loading. The average burnup increased by about 48 MWd/kg U and it was confirmed that the excess reactivity can be controlled with the present design and arrangement of control elements throughout the core's life. Another major design change studied was the effect of installing an internal beryllium reflector upon cycle length. Exposure dependent eigenvalue predictions indicate that the actual benefit could be twice as large as that originally assessed via beginning-of-life (BOL) analyses.

  18. Inhibition of gustatory plasticity due to acute nicotine exposure in the nematode Caenorhabditis elegans.

    PubMed

    Matsuura, Tetsuya; Miura, Hitoshi; Nishino, Asuka

    2013-11-01

    The present study investigated the effect of nicotine exposure on gustatory plasticity in the nematode Caenorhabditis elegans. The chemotactic response of wild-type N2 nematodes pre-exposed to 100mM NaCl with 3.0mM nicotine was almost the same as that of mock-conditioned nematodes unexposed to NaCl; however, the response of N2 nematodes pre-exposed to NaCl without nicotine was significantly lower than that of mock-conditioned nematodes. These results indicate that gustatory plasticity is inhibited by acute nicotine exposure. Inhibition of gustatory plasticity was observed when cat-2 mutants with a defect in dopamine biosynthesis were pre-exposed to NaCl with 3.0mM nicotine. Acute nicotine exposure did not cause inhibition of gustatory plasticity in bas-1 mutants, which had defects in both serotonin and dopamine secretion, and tph-1 mutants, which had a defect in serotonin secretion only. However, inhibition of gustatory plasticity was observed when bas-1 and tph-1 mutants were maintained on a growth plate that included serotonin. These results suggest that serotonin signaling plays an essential role in the modulation of the acute effects of nicotine.

  19. Disrupted Nitric Oxide Metabolism from Type II Diabetes and Acute Exposure to Particulate Air Pollution.

    PubMed

    Pettit, Ashley P; Kipen, Howard; Laumbach, Robert; Ohman-Strickland, Pamela; Kelly-McNeill, Kathleen; Cepeda, Clarimel; Fan, Zhi-Hua; Amorosa, Louis; Lubitz, Sara; Schneider, Stephen; Gow, Andrew

    2015-01-01

    Type II diabetes is an established cause of vascular impairment. Particulate air pollution is known to exacerbate cardiovascular and respiratory conditions, particularly in susceptible populations. This study set out to determine the impact of exposure to traffic pollution, with and without particle filtration, on vascular endothelial function in Type II diabetes. Endothelial production of nitric oxide (NO) has previously been linked to vascular health. Reactive hyperemia induces a significant increase in plasma nitrite, the proximal metabolite of NO, in healthy subjects, while diabetics have a lower and more variable level of response. Twenty type II diabetics and 20 controls (ages 46-70 years) were taken on a 1.5 hr roadway traffic air pollution exposure as passengers. We analyzed plasma nitrite, as a measure of vascular function, using forearm ischemia to elicit a reactive hyperemic response before and after exposure to one ride with and one without filtration of the particle components of pollution. Control subjects displayed a significant increase in plasma nitrite levels during reactive hyperemia. This response was no longer present following exposure to traffic air pollution, but did not vary with whether or not the particle phase was filtered out. Diabetics did not display an increase in nitrite levels following reactive hyperemia. This response was not altered following pollution exposure. These data suggest that components of acute traffic pollution exposure diminish vascular reactivity in non-diabetic individuals. It also confirms that type II diabetics have a preexisting diminished ability to appropriately respond to a vascular challenge, and that traffic pollution exposure does not cause a further measureable acute change in plasma nitrite levels in Type II diabetics.

  20. Disrupted Nitric Oxide Metabolism from Type II Diabetes and Acute Exposure to Particulate Air Pollution

    PubMed Central

    Pettit, Ashley P.; Kipen, Howard; Laumbach, Robert; Ohman-Strickland, Pamela; Kelly-McNeill, Kathleen; Cepeda, Clarimel; Fan, Zhi-Hua; Amorosa, Louis; Lubitz, Sara; Schneider, Stephen; Gow, Andrew

    2015-01-01

    Type II diabetes is an established cause of vascular impairment. Particulate air pollution is known to exacerbate cardiovascular and respiratory conditions, particularly in susceptible populations. This study set out to determine the impact of exposure to traffic pollution, with and without particle filtration, on vascular endothelial function in Type II diabetes. Endothelial production of nitric oxide (NO) has previously been linked to vascular health. Reactive hyperemia induces a significant increase in plasma nitrite, the proximal metabolite of NO, in healthy subjects, while diabetics have a lower and more variable level of response. Twenty type II diabetics and 20 controls (ages 46–70 years) were taken on a 1.5hr roadway traffic air pollution exposure as passengers. We analyzed plasma nitrite, as a measure of vascular function, using forearm ischemia to elicit a reactive hyperemic response before and after exposure to one ride with and one without filtration of the particle components of pollution. Control subjects displayed a significant increase in plasma nitrite levels during reactive hyperemia. This response was no longer present following exposure to traffic air pollution, but did not vary with whether or not the particle phase was filtered out. Diabetics did not display an increase in nitrite levels following reactive hyperemia. This response was not altered following pollution exposure. These data suggest that components of acute traffic pollution exposure diminish vascular reactivity in non-diabetic individuals. It also confirms that type II diabetics have a preexisting diminished ability to appropriately respond to a vascular challenge, and that traffic pollution exposure does not cause a further measureable acute change in plasma nitrite levels in Type II diabetics. PMID:26656561

  1. In vitro acute exposure to DEHP affects oocyte meiotic maturation, energy and oxidative stress parameters in a large animal model.

    PubMed

    Ambruosi, Barbara; Uranio, Manuel Filioli; Sardanelli, Anna Maria; Pocar, Paola; Martino, Nicola Antonio; Paternoster, Maria Stefania; Amati, Francesca; Dell'Aquila, Maria Elena

    2011-01-01

    Phthalates are ubiquitous environmental contaminants because of their use in plastics and other common consumer products. Di-(2-ethylhexyl) phthalate (DEHP) is the most abundant phthalate and it impairs fertility by acting as an endocrine disruptor. The aim of the present study was to analyze the effects of in vitro acute exposure to DEHP on oocyte maturation, energy and oxidative status in the horse, a large animal model. Cumulus cell (CC) apoptosis and oxidative status were also investigated. Cumulus-oocyte complexes from the ovaries of slaughtered mares were cultured in vitro in presence of 0.12, 12 and 1200 µM DEHP. After in vitro maturation (IVM), CCs were removed and evaluated for apoptosis (cytological assessment and TUNEL) and intracellular reactive oxygen species (ROS) levels. Oocytes were evaluated for nuclear chromatin configuration. Matured (Metaphase II stage; MII) oocytes were further evaluated for cytoplasmic energy and oxidative parameters. DEHP significantly inhibited oocyte maturation when added at low doses (0.12 µM; P<0.05). This effect was related to increased CC apoptosis (P<0.001) and reduced ROS levels (P<0.0001). At higher doses (12 and 1200 µM), DEHP induced apoptosis (P<0.0001) and ROS increase (P<0.0001) in CCs without affecting oocyte maturation. In DEHP-exposed MII oocytes, mitochondrial distribution patterns, apparent energy status (MitoTracker fluorescence intensity), intracellular ROS localization and levels, mt/ROS colocalization and total SOD activity did not vary, whereas increased ATP content (P<0.05), possibly of glycolytic origin, was found. Co-treatment with N-Acetyl-Cysteine reversed apoptosis and efficiently scavenged excessive ROS in DEHP-treated CCs without enhancing oocyte maturation. In conclusion, acute in vitro exposure to DEHP inhibits equine oocyte maturation without altering ooplasmic energy and oxidative stress parameters in matured oocytes which retain the potential to be fertilized and develop into embryos

  2. Acute phase response, inflammation and metabolic syndrome biomarkers of Libby asbestos exposure.

    PubMed

    Shannahan, Jonathan H; Alzate, Oscar; Winnik, Witold M; Andrews, Debora; Schladweiler, Mette C; Ghio, Andrew J; Gavett, Stephen H; Kodavanti, Urmila P

    2012-04-15

    Identification of biomarkers assists in the diagnosis of disease and the assessment of health risks from environmental exposures. We hypothesized that rats exposed to Libby amphibole (LA) would present with a unique serum proteomic profile which could help elucidate epidemiologically-relevant biomarkers. In four experiments spanning varied protocols and temporality, healthy (Wistar Kyoto, WKY; and F344) and cardiovascular compromised (CVD) rat models (spontaneously hypertensive, SH; and SH heart failure, SHHF) were intratracheally instilled with saline (control) or LA. Serum biomarkers of cancer, inflammation, metabolic syndrome (MetS), and the acute phase response (APR) were analyzed. All rat strains exhibited acute increases in α-2-macroglobulin, and α1-acid glycoprotein. Among markers of inflammation, lipocalin-2 was induced in WKY, SH and SHHF and osteopontin only in WKY after LA exposure. While rat strain- and age-related changes were apparent in MetS biomarkers, no LA effects were evident. The cancer marker mesothelin was increased only slightly at 1 month in WKY in one of the studies. Quantitative Intact Proteomic profiling of WKY serum at 1 day or 4 weeks after 4 weekly LA instillations indicated no oxidative protein modifications, however APR proteins were significantly increased. Those included serine protease inhibitor, apolipoprotein E, α-2-HS-glycoprotein, t-kininogen 1 and 2, ceruloplasmin, vitamin D binding protein, serum amyloid P, and more 1 day after last LA exposure. All changes were reversible after a short recovery regardless of the acute or long-term exposures. Thus, LA exposure induces an APR and systemic inflammatory biomarkers that could have implications in systemic and pulmonary disease in individuals exposed to LA.

  3. Resistin deficiency in mice has no effect on pulmonary responses induced by acute ozone exposure

    PubMed Central

    Razvi, Shehla S.; Richards, Jeremy B.; Malik, Farhan; Cromar, Kevin R.; Price, Roger E.; Bell, Cynthia S.; Weng, Tingting; Atkins, Constance L.; Spencer, Chantal Y.; Cockerill, Katherine J.; Alexander, Amy L.; Blackburn, Michael R.; Alcorn, Joseph L.; Haque, Ikram U.

    2015-01-01

    Acute exposure to ozone (O3), an air pollutant, causes pulmonary inflammation, airway epithelial desquamation, and airway hyperresponsiveness (AHR). Pro-inflammatory cytokines—including IL-6 and ligands of chemokine (C-X-C motif) receptor 2 [keratinocyte chemoattractant (KC) and macrophage inflammatory protein (MIP)-2], TNF receptor 1 and 2 (TNF), and type I IL-1 receptor (IL-1α and IL-1β)—promote these sequelae. Human resistin, a pleiotropic hormone and cytokine, induces expression of IL-1α, IL-1β, IL-6, IL-8 (the human ortholog of murine KC and MIP-2), and TNF. Functional differences exist between human and murine resistin; yet given the aforementioned observations, we hypothesized that murine resistin promotes O3-induced lung pathology by inducing expression of the same inflammatory cytokines as human resistin. Consequently, we examined indexes of O3-induced lung pathology in wild-type and resistin-deficient mice following acute exposure to either filtered room air or O3. In wild-type mice, O3 increased bronchoalveolar lavage fluid (BALF) resistin. Furthermore, O3 increased lung tissue or BALF IL-1α, IL-6, KC, TNF, macrophages, neutrophils, and epithelial cells in wild-type and resistin-deficient mice. With the exception of KC, which was significantly greater in resistin-deficient compared with wild-type mice, no genotype-related differences in the other indexes existed following O3 exposure. O3 caused AHR to acetyl-β-methylcholine chloride (methacholine) in wild-type and resistin-deficient mice. However, genotype-related differences in airway responsiveness to methacholine were nonexistent subsequent to O3 exposure. Taken together, these data demonstrate that murine resistin is increased in the lungs of wild-type mice following acute O3 exposure but does not promote O3-induced lung pathology. PMID:26386120

  4. Resistin deficiency in mice has no effect on pulmonary responses induced by acute ozone exposure.

    PubMed

    Razvi, Shehla S; Richards, Jeremy B; Malik, Farhan; Cromar, Kevin R; Price, Roger E; Bell, Cynthia S; Weng, Tingting; Atkins, Constance L; Spencer, Chantal Y; Cockerill, Katherine J; Alexander, Amy L; Blackburn, Michael R; Alcorn, Joseph L; Haque, Ikram U; Johnston, Richard A

    2015-11-15

    Acute exposure to ozone (O3), an air pollutant, causes pulmonary inflammation, airway epithelial desquamation, and airway hyperresponsiveness (AHR). Pro-inflammatory cytokines-including IL-6 and ligands of chemokine (C-X-C motif) receptor 2 [keratinocyte chemoattractant (KC) and macrophage inflammatory protein (MIP)-2], TNF receptor 1 and 2 (TNF), and type I IL-1 receptor (IL-1α and IL-1β)-promote these sequelae. Human resistin, a pleiotropic hormone and cytokine, induces expression of IL-1α, IL-1β, IL-6, IL-8 (the human ortholog of murine KC and MIP-2), and TNF. Functional differences exist between human and murine resistin; yet given the aforementioned observations, we hypothesized that murine resistin promotes O3-induced lung pathology by inducing expression of the same inflammatory cytokines as human resistin. Consequently, we examined indexes of O3-induced lung pathology in wild-type and resistin-deficient mice following acute exposure to either filtered room air or O3. In wild-type mice, O3 increased bronchoalveolar lavage fluid (BALF) resistin. Furthermore, O3 increased lung tissue or BALF IL-1α, IL-6, KC, TNF, macrophages, neutrophils, and epithelial cells in wild-type and resistin-deficient mice. With the exception of KC, which was significantly greater in resistin-deficient compared with wild-type mice, no genotype-related differences in the other indexes existed following O3 exposure. O3 caused AHR to acetyl-β-methylcholine chloride (methacholine) in wild-type and resistin-deficient mice. However, genotype-related differences in airway responsiveness to methacholine were nonexistent subsequent to O3 exposure. Taken together, these data demonstrate that murine resistin is increased in the lungs of wild-type mice following acute O3 exposure but does not promote O3-induced lung pathology. Copyright © 2015 the American Physiological Society.

  5. Acute Lead Exposure Increases Arterial Pressure: Role of the Renin-Angiotensin System

    PubMed Central

    Simões, Maylla Ronacher; Ribeiro Júnior, Rogério F.; Vescovi, Marcos Vinícius A.; de Jesus, Honério C.; Padilha, Alessandra S.; Stefanon, Ivanita; Vassallo, Dalton V.; Salaices, Mercedes; Fioresi, Mirian

    2011-01-01

    Background Chronic lead exposure causes hypertension and cardiovascular disease. Our purpose was to evaluate the effects of acute exposure to lead on arterial pressure and elucidate the early mechanisms involved in the development of lead-induced hypertension. Methodology/Principal Findings Wistar rats were treated with lead acetate (i.v. bolus dose of 320 µg/Kg), and systolic arterial pressure, diastolic arterial pressure and heart rate were measured during 120 min. An increase in arterial pressure was found, and potential roles of the renin-angiotensin system, Na+,K+-ATPase and the autonomic reflexes in this change in the increase of arterial pressure found were evaluated. In anesthetized rats, lead exposure: 1) produced blood lead levels of 37±1.7 µg/dL, which is below the reference blood concentration (60 µg/dL); 2) increased systolic arterial pressure (Ct: 109±3 mmHg vs Pb: 120±4 mmHg); 3) increased ACE activity (27% compared to Ct) and Na+,K+-ATPase activity (125% compared to Ct); and 4) did not change the protein expression of the α1-subunit of Na+,K+-ATPase, AT1 and AT2. Pre-treatment with an AT1 receptor blocker (losartan, 10 mg/Kg) or an ACE inhibitor (enalapril, 5 mg/Kg) blocked the lead-induced increase of arterial pressure. However, a ganglionic blockade (hexamethonium, 20 mg/Kg) did not prevent lead's hypertensive effect. Conclusion Acute exposure to lead below the reference blood concentration increases systolic arterial pressure by increasing angiotensin II levels due to ACE activation. These findings offer further evidence that acute exposure to lead can trigger early mechanisms of hypertension development and might be an environmental risk factor for cardiovascular disease. PMID:21494558

  6. Acute mountain sickness: medical problems associated with acute and subacute exposure to hypobaric hypoxia

    PubMed Central

    Clarke, C

    2006-01-01

    This article summarises the medical problems of travel to altitudes above 3000 m. These are caused by chronic hypoxia. Acute mountain sickness (AMS), a self limiting common illness is almost part of normal acclimatisation—a transient condition lasting for several days. However, in <2% of people staying above 4000 m, serious illnesses related to hypoxia develop – high altitude pulmonary oedema and cerebral oedema. These are potentially fatal but can be largely avoided by gradual ascent. Short vacations, pressure from travel companies and peer groups often encourage ascent to 4000 m more rapidly than is prudent. Sensible guidelines for ascent are outlined, clinical features, management and treatment of these conditions. PMID:17099095

  7. [Cutaneous damage after acute exposure to ionizing radiation: decisive for the prognosis of radiation accident victims].

    PubMed

    Dörr, H; Baier, T; Meineke, V

    2013-12-01

    The cutaneous radiation syndrome includes all deterministic effects on the skin and visible parts of the mucosa from ionizing radiation. The Intensity and duration of radiation-induced skin symptoms depend on the kind and quality of ionizing radiation. The aim of this study was the investigation of the importance of the time of the development of radiation induced-skin effects on the prognosis of radiation accident victims. Clinical data about radiation accident victims from the database SEARCH were used. 211 cases with good documentation regarding radiation-induced skin effects were selected. From these 211 patients, 166 survived the acute phase of the acute radiation syndrome, while 45 died during the acute phase. Among those patients who did not survive the acute phase, 82.2 % showed their first documented radiation-induced skin symptoms during the first 3 days after radiation exposure. Of those patients whose first documented radiation-induced skin symptoms appeared on or after day four, 94.2 % survived the acute phase. The time to the occurrence of the first radiation-induced skin effects is diagnostically significant. The skin plays an important role in the clinical course of radiation syndromes and in the development of radiation-induced multi-organ failure. In a retrospective data analysis like this, the quality of data might be a limitation.

  8. Acute and chronic exposure to Tyrophagus putrescentiae induces allergic pulmonary response in a murine model

    PubMed Central

    Nuñez, Nailê Karine; dos Santos Dutra, Moisés; Barbosa, Gustavo Leivas; Morassutti, Alessandra Loureiro; de Souza, Rodrigo Godinho; Vargas, Mauro Henrique Moraes; Antunes, Géssica Luana; Silveira, Josiane Silva; da Silva, Guilherme Liberato; Pitrez, Paulo Márcio

    2016-01-01

    Background Tyrophagus putrescentiae (Tp) is a source of aeroallergen that causes allergic diseases. Objective To describe an acute and chronic murine model of allergic asthma with Tp extract with no systemic sensitization and no use of adjuvant. Methods Mites from dust sample were cultured and a raw extract was produced. Female BALB/c mice (6-8 weeks) were challenged intranasally with Tp extract or Dulbecco's phosphate-buffered saline, for 10 consecutive days (acute protocol) or for 6 weeks (chronic protocol). Twenty-four hours after the last intranasal challenge, bronchoalveolar lavage fluid (BALF) was performed for total and differential cells count, cytokine analysis, and eosinophil peroxidase activity. Lung tissue was also removed for histopathologic analysis. Results Tp extract has shown a significant increase in total cells count from BALF as well as an increase in absolute eosinophils count, eosinophil peroxidase activity, interleukin (IL)-5 and IL-13 levels, in both acute and chronic protocols. Peribronchovascular infiltrate, goblet cells hyperplasia and collagen deposition were shown in the airways of acute and chronic Tp-exposed mice. Conclusion Our data suggest that the intranasal exposure to Tp extract, with no systemic sensitization and no use of adjuvants, induces a robust allergic inflammation in the lungs of mice, in both acute and chronic models. Our Tp extract seems to be a potent allergen extract which may be used in asthma model studies. PMID:26844220

  9. Assessment of environmental public exposure from a hypothetical nuclear accident for Unit-1 Bushehr nuclear power plant.

    PubMed

    Sohrabi, M; Ghasemi, M; Amrollahi, R; Khamooshi, C; Parsouzi, Z

    2013-05-01

    Unit-1 of the Bushehr nuclear power plant (BNPP-1) is a VVER-type reactor with 1,000-MWe power constructed near Bushehr city at the coast of the Persian Gulf, Iran. The reactor has been recently operational to near its full power. The radiological impact of nuclear power plant (NPP) accidents is of public concern, and the assessment of radiological consequences of any hypothetical nuclear accident on public exposure is vital. The hypothetical accident scenario considered in this paper is a design-basis accident, that is, a primary coolant leakage to the secondary circuit. This scenario was selected in order to compare and verify the results obtained in the present paper with those reported in the Final Safety Analysis Report (FSAR 2007) of the BNPP-1 and to develop a well-proven methodology that can be used to study other and more severe hypothetical accident scenarios for this reactor. In the present study, the version 2.01 of the PC COSYMA code was applied. In the early phase of the accidental releases, effective doses (from external and internal exposures) as well as individual and collective doses (due to the late phase of accidental releases) were evaluated. The surrounding area of the BNPP-1 within a radius of 80 km was subdivided into seven concentric rings and 16 sectors, and distribution of population and agricultural products was calculated for this grid. The results show that during the first year following the modeled hypothetical accident, the effective doses do not exceed the limit of 5 mSv, for the considered distances from the BNPP-1. The results obtained in this study are in good agreement with those in the FSAR-2007 report. The agreement obtained is in light of many inherent uncertainties and variables existing in the two modeling procedures applied and proves that the methodology applied here can also be used to model other severe hypothetical accident scenarios of the BNPP-1 such as a small and large break in the reactor coolant system as well

  10. Acute and chronic ethanol exposure differentially alters alcohol dehydrogenase and aldehyde dehydrogenase activity in the zebrafish liver.

    PubMed

    Tran, Steven; Nowicki, Magda; Chatterjee, Diptendu; Gerlai, Robert

    2015-01-02

    Chronic ethanol exposure paradigms have been successfully used in the past to induce behavioral and central nervous system related changes in zebrafish. However, it is currently unknown whether chronic ethanol exposure alters ethanol metabolism in adult zebrafish. In the current study we examine the effect of acute ethanol exposure on adult zebrafish behavioral responses, as well as alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) activity in the liver. We then examine how two different chronic ethanol exposure paradigms (continuous and repeated ethanol exposure) alter behavioral responses and liver enzyme activity during a subsequent acute ethanol challenge. Acute ethanol exposure increased locomotor activity in a dose-dependent manner. ADH activity was shown to exhibit an inverted U-shaped curve and ALDH activity was decreased by ethanol exposure at all doses. During the acute ethanol challenge, animals that were continuously housed in ethanol exhibited a significantly reduced locomotor response and increased ADH activity, however, ALDH activity did not change. Zebrafish that were repeatedly exposed to ethanol demonstrated a small but significant attenuation of the locomotor response during the acute ethanol challenge but ADH and ALDH activity was similar to controls. Overall, we identified two different chronic ethanol exposure paradigms that differentially alter behavioral and physiological responses in zebrafish. We speculate that these two paradigms may allow dissociation of central nervous system-related and liver enzyme-dependent ethanol induced changes in zebrafish.

  11. Prior exposure to repeated immobilization or chronic unpredictable stress protects from some negative sequels of an acute immobilization.

    PubMed

    Pastor-Ciurana, Jordi; Rabasa, Cristina; Ortega-Sánchez, Juan A; Sanchís-Ollè, Maria; Gabriel-Salazar, Marina; Ginesta, Marta; Belda, Xavier; Daviu, Núria; Nadal, Roser; Armario, Antonio

    2014-05-15

    Exposure to chronic unpredictable stress (CUS) is gaining acceptance as a putative animal model of depression. However, there is evidence that chronic exposure to stress can offer non-specific stress protection from some effects of acute superimposed stressors. We then compared in adult male rats the protection afforded by prior exposure to CUS with the one offered by repeated immobilization on boards (IMO) regarding some of the negative consequences of an acute exposure to IMO. Repeated exposure to IMO protected from the negative consequences of an acute IMO on activity in an open-field, saccharin intake and body weight gain. Active coping during IMO (struggling) was markedly reduced by repeated exposure to the same stressor, but it was not affected by a prior history of CUS, suggesting that our CUS protocol does not appear to impair active coping responses. CUS exposure itself caused a strong reduction of activity in the open-field but appeared to protect from the hypo-activity induced by acute IMO. Moreover, prior CUS offered partial protection from acute IMO-induced reduction of saccharin intake and body weight gain. It can be concluded that a prior history of CUS protects from some of the negative consequences of exposure to a novel severe stressor, suggesting the development of partial cross-adaptation whose precise mechanisms remain to be studied.

  12. Short term respiratory effects of acute exposure to chlorine due to a swimming pool accident

    PubMed Central

    Agabiti, N; Ancona, C; Forastiere, F; Di, N; Lo, P; Corbo, G; D'Orsi, F; Perucci, C

    2001-01-01

    OBJECTIVE—Acute exposure to chlorine causes lung damage, and recovery may proceed slowly for several weeks. The short term respiratory effects of acute chlorine inhalation during a swimming pool accident were examined.
METHODS—A total of 282 subjects (134 children, aged <14 years) inhaled hydrogen chloride and sodium hypochlorite during an accident caused by a malfunction of the water chlorinating system in a community pool in Rome in 1998. Most people received bronchodilators and cortisone at the emergency room; five children were admitted to hospital. A total of 260 subjects (92.2%) were interviewed about duration of exposure (<3, 3-5, >5 minutes), intensity of exposure (not at all or a little, a moderate amount, a lot), and respiratory symptoms. Lung function was measured in 184 people (82 children) after 15-30 days. The effects of exposure to chlorine were analysed through multiple linear regression, separately in adults and in children.
RESULTS—Acute respiratory symptoms occurred among 66.7% of adults and 71.6% of children. The incidences were highest among those who had chronic respiratory disease and had a longer duration of exposure. In about 30% of the subjects, respiratory symptoms persisted for 15-30 days after the accident. Lung function levels were lower in those who reported a high intensity of exposure than in those who reported low exposure, both in children and in adults (mean (95% confidence interval (95% CI)) differences in forced expiratory volume in 1 second (FEV1,) were −109 (−310 to 93) ml, and −275 (−510 to −40) ml, respectively).
CONCLUSION—Persistent symptoms and lung function impairment were found up to 1 month after the incident. Although community pool accidents happen rarely, the medical community needs to be alerted to the possible clinical and physiological sequelae, especially among susceptible people.


Keywords: accidental exposure; chlorine gas; lung function PMID:11351056

  13. Cancer mortality in relation to monitoring for radionuclide exposure in three UK nuclear industry workforces.

    PubMed Central

    Carpenter, L. M.; Higgins, C. D.; Douglas, A. J.; Maconochie, N. E.; Omar, R. Z.; Fraser, P.; Beral, V.; Smith, P. G.

    1998-01-01

    Cancer mortality in 40,761 employees of three UK nuclear industry facilities who had been monitored for external radiation exposure was examined according to whether they had also been monitored for possible internal exposure to tritium, plutonium or other radionuclides (uranium, polonium, actinium or other unspecified). Death rates from cancer were compared both with national rates and with rates in radiation workers not monitored for exposure to any radionuclides. Among workers monitored for tritium exposure, overall cancer mortality was significantly below national rates [standardized mortality ratio (SMR) = 83, 165 deaths; 2P = 0.02] and none of the cancer-specific death rates was significantly above either the national average or rates in non-monitored workers. Although the overall death rate from cancer in workers monitored for plutonium exposure was also significantly low relative to national rates (SMR = 89, 581 deaths; 2P = 0.005), mortality from pleural cancer was significantly raised (SMR = 357, nine deaths; 2P = 0.002); none of the rates differed significantly from those of non-monitored workers. Workers monitored for radionuclides other than tritium or plutonium also had a death rate from all cancers combined that was below the national average (SMR = 86, 418 deaths; 2P = 0.002) but prostatic cancer mortality was raised both in relation to death rates in the general population (SMR = 153, 37 deaths; 2P = 0.02) and to death rates in radiation workers who had not been monitored for exposure to any radionuclide [rate ratio (RR) = 1.65; 2P = 0.03]. Mortality from cancer of the lung was also significantly increased in workers monitored for other radionuclides compared with those of radiation workers not monitored for exposure to radionuclides (RR = 1.31, 164 deaths; 2P = 0.01). For cancers of the lung, prostate and all cancers combined, death rates in monitored workers were examined according to the timing and duration of monitoring for radionuclide

  14. The assessment of radiation exposures in native American communities from nuclear weapons testing in Nevada

    SciTech Connect

    Frohmberg, E.; Goble, R.; Sanchez, V.; Quigley, D.

    2000-02-01

    Native Americans residing in a broad region downwind from the Nevada Test Site during the 1950s and 1960s received significant radiation exposures from nuclear weapons testing. Because of differences in diet, activities, and housing, their radiation exposures are only very imperfectly represented in the Department of Energy dose reconstructions. There are important missing pathways, including exposures to radioactive iodine from eating small game. The dose reconstruction model assumptions about cattle feeding practices across a year are unlikely to apply to the native communities as are other model assumptions about diet. Thus exposures from drinking milk and eating vegetables have not yet been properly estimated for these communities. Through consultations with members of the affected communities, these deficiencies could be corrected and the dose reconstruction extended to Native Americans. An illustration of the feasibility of extending the dose reconstruction is provided by a sample calculation to estimate radiation exposures to the thyroid from eating radio-iodine-contaminated rabbit thyroids after the Dedan test. The illustration is continued with a discussion of how the calculation results may be used to make estimates for other tests and other locations.

  15. The assessment of radiation exposures in Native American communities from nuclear weapons testing in Nevada.

    PubMed

    Frohmberg, E; Goble, R; Sanchez, V; Quigley, D

    2000-02-01

    Native Americans residing in a broad region downwind from the Nevada Test Site during the 1950s and 1960s received significant radiation exposures from nuclear weapons testing. Because of differences in diet, activities, and housing, their radiation exposures are only very imperfectly represented in the Department of Energy dose reconstructions. There are important missing pathways, including exposures to radioactive iodine from eating small game. The dose reconstruction model assumptions about cattle feeding practices across a year are unlikely to apply to the native communities as are other model assumptions about diet. Thus exposures from drinking milk and eating vegetables have not yet been properly estimated for these communities. Through consultations with members of the affected communities, these deficiencies could be corrected and the dose reconstruction extended to Native Americans. An illustration of the feasibility of extending the dose reconstruction is provided by a sample calculation to estimate radiation exposures to the thyroid from eating radio-iodine-contaminated rabbit thyroids after the Sedan test. The illustration is continued with a discussion of how the calculation results may be used to make estimates for other tests and other locations.

  16. Proposed standards for acute exposure to low enrichment uranium for compliance with 10 CFR 70.61.

    PubMed

    Kathren, Ronald L; Burklin, Richard K

    2008-08-01

    Title 10, Code of Federal Regulations Part 70, puts forth requirements for licensure of special nuclear material including specific risk criteria for acute intakes based on biological effects. Standards for acute oral and inhalation intakes of soluble low enrichment are proposed for the three levels of biological effects given in the regulations. These levels were developed largely from available human data and have a large measure of conservatism. The proposed threshold for life endangerment was 500 mg for acute inhalation intakes and 2,500 mg for acute ingestion intakes. Acute intakes of 1,400 mg for ingestion and 100 mg for inhalation are proposed as thresholds for irreversible or serious long lasting health effects. For minor transient health effects, the proposed levels are 410 and 30 mg, respectively, for acute ingestion and inhalation intakes. For acute intakes below these levels, no demonstrable toxicological effects are anticipated.

  17. Occupational exposure to ionising radiation and mortality among workers of the former Spanish Nuclear Energy Board.

    PubMed Central

    Rodríguez Artalejo, F; Castaño Lara, S; de Andrés Manzano, B; García Ferruelo, M; Iglesias Martín, L; Calero, J R

    1997-01-01

    OBJECTIVES: Firstly, to ascertain whether mortality among workers of the former Spanish Nuclear Energy Board (Junta de Energía Nuclear-JEN) was higher than that for the Spanish population overall; and secondly, if this were so, to ascertain whether this difference was associated with exposure to ionising radiation. METHODS: A retrospective follow up of a cohort of 5657 workers was carried out for the period 1954-92. Cohort mortality was compared with that for the Spanish population overall, with standardised mortality ratios (SMRs) adjusted for sex, age, and calendar period. Also, Poisson models were used to analyse mortality from lung cancer in the cohort by level of exposure to ionising radiation. RESULTS: Workers' median and mean cumulative exposures were 4.04 and 11.42 mSv, respectively. Mean annual exposure was 1.33 mSv. Excess mortality due to bone tumours was found for the cohort as a whole (six deaths observed; SMR 2.95; 95% confidence interval (95% CI) 1.08 to 6.43). Among miners, excess mortality was found for non-malignant respiratory diseases (SMR 2.94; 95% CI 2.27 to 3.75), and for lung cancer bordering on statistical significance (SMR 1.50; 95% CI 0.96 to 2.23; P = 0.055). Relative risks of dying of lung cancer from ionising radiation in the dose quartiles 2, 3, and 4 versus the lowest dose quartile, were 1.00, 1.64, and 0.94, respectively. CONCLUSIONS: Excess mortality from lung cancer was found among JEN miners. Nevertheless, no clear relation was found between mortality from lung cancer and level of exposure to ionising radiation in the JEN cohort. Continued follow up of the cohort is required to confirm excess mortality from bone tumours. PMID:9155782

  18. Occupational exposure to ionising radiation and mortality among workers of the former Spanish Nuclear Energy Board.

    PubMed

    Rodríguez Artalejo, F; Castaño Lara, S; de Andrés Manzano, B; García Ferruelo, M; Iglesias Martín, L; Calero, J R

    1997-03-01

    Firstly, to ascertain whether mortality among workers of the former Spanish Nuclear Energy Board (Junta de Energía Nuclear-JEN) was higher than that for the Spanish population overall; and secondly, if this were so, to ascertain whether this difference was associated with exposure to ionising radiation. A retrospective follow up of a cohort of 5657 workers was carried out for the period 1954-92. Cohort mortality was compared with that for the Spanish population overall, with standardised mortality ratios (SMRs) adjusted for sex, age, and calendar period. Also, Poisson models were used to analyse mortality from lung cancer in the cohort by level of exposure to ionising radiation. Workers' median and mean cumulative exposures were 4.04 and 11.42 mSv, respectively. Mean annual exposure was 1.33 mSv. Excess mortality due to bone tumours was found for the cohort as a whole (six deaths observed; SMR 2.95; 95% confidence interval (95% CI) 1.08 to 6.43). Among miners, excess mortality was found for non-malignant respiratory diseases (SMR 2.94; 95% CI 2.27 to 3.75), and for lung cancer bordering on statistical significance (SMR 1.50; 95% CI 0.96 to 2.23; P = 0.055). Relative risks of dying of lung cancer from ionising radiation in the dose quartiles 2, 3, and 4 versus the lowest dose quartile, were 1.00, 1.64, and 0.94, respectively. Excess mortality from lung cancer was found among JEN miners. Nevertheless, no clear relation was found between mortality from lung cancer and level of exposure to ionising radiation in the JEN cohort. Continued follow up of the cohort is required to confirm excess mortality from bone tumours.

  19. Tumor necrosis factor-α induced protein 6 attenuates acute lung injury following paraquat exposure.

    PubMed

    Xu, Jiajun; Zhen, Jiantao; Zhu, Jingfa; Lin, Qingming

    2016-01-01

    Paraquat exposure commonly occurs in the developing countries and the mortality rate is high. However, there is currently no consensus on the efficacy of treatment for paraquat exposure. The study was aimed to explore the effects of tumor necrosis factor-α (TNF-α) induced protein 6 (TSG-6) on acute lung injury (ALI) following paraquat exposure in rats. Male Sprague-Dawley (SD) rats were randomly divided into the sham group (n = 8), the paraquat group (n = 8), and the paraquat TSG-6-treated group (n = 8). Rats were administered with 50 mg/kg of paraquat intraperitoneally. At 1 h after exposure, rats were treated with 30 μg of recombinant human TSG-6 (rhTSG-6) intraperitoneally. After 6 h of exposure, ALI scores were evaluated by histology and the expression of pro-inflammatory cytokines in lung was assayed using real-time RT-PCR. ALI scores were significantly lower in the paraquat TSG-6-treated group, compared with the paraquat group (p < 0.05). The expression of interleukin (IL)-1β, IL-6, and TNF-α mRNA was significantly lower in the paraquat TSG-6-treated group, compared with the paraquat group (p < 0.01, respectively). Administration of rhTSG-6 attenuates ALI following paraquat exposure by suppressing inflammatory response.

  20. Acute mobile phones exposure affects frontal cortex hemodynamics as evidenced by functional near-infrared spectroscopy.

    PubMed

    Curcio, Giuseppe; Ferrara, Michele; Limongi, Tania; Tempesta, Daniela; Di Sante, Gabriele; De Gennaro, Luigi; Quaresima, Valentina; Ferrari, Marco

    2009-05-01

    This study aimed to evaluate by functional near-infrared spectroscopy (fNIRS), the effects induced by an acute exposure (40 mins) to a GSM (Global System for Mobile Communications) signal emitted by a mobile phone (MP) on the oxygenation of the frontal cortex. Eleven healthy volunteers underwent two sessions (Real and Sham exposure) after a crossover, randomized, double-blind paradigm. The whole procedure lasted 60 mins: 10-mins baseline (Bsl), 40-mins (Exposure), and 10-mins recovery (Post-Exp). Together with frontal hemodynamics, heart rate, objective and subjective vigilance, and self-evaluation of subjective symptoms were also assessed. The fNIRS results showed a slight influence of the GSM signal on frontal cortex, with a linear increase in [HHb] as a function of time in the Real exposure condition (F(4,40)=2.67; P=0.04). No other measure showed any GSM exposure-dependent changes. These results suggest that fNIRS is a convenient tool for safely and noninvasively investigating the cortical activation in MP exposure experimental settings. Given the short-term effects observed in this study, the results should be confirmed on a larger sample size and using a multichannel instrument that allows the investigation of a wider portion of the frontal cortex.

  1. Transcriptome Profiling of the Newborn Mouse Lung Response to Acute Ozone Exposure

    PubMed Central

    Loader, Joan E.; White, Carl W.; Dakhama, Azzeddine

    2014-01-01

    Ozone pollution is associated with adverse effects on respiratory health in adults and children but its effects on the neonatal lung remain unknown. This study was carried out to define the effect of acute ozone exposure on the neonatal lung and to profile the transcriptome response. Newborn mice were exposed to ozone or filtered air for 3h. Total RNA was isolated from lung tissues at 6 and 24h after exposure and was subjected to microarray gene expression analysis. Compared to filtered air-exposed littermates, ozone-exposed newborn mice developed a small but significant neutrophilic airway response associated with increased CXCL1 and CXCL5 expression in the lung. Transcriptome analysis indicated that 455 genes were down-regulated and 166 genes were up-regulated by at least 1.5-fold at 6h post-ozone exposure (t-test, p < .05). At 24h, 543 genes were down-regulated and 323 genes were up-regulated in the lungs of ozone-exposed, compared to filtered air-exposed, newborn mice (t-test, p < .05). After controlling for false discovery rate, 50 genes were identified as significantly down-regulated and only a few (RORC, GRP, VREB3, and CYP2B6) were up-regulated at 24h post-ozone exposure (q < .05). Gene ontology enrichment analysis revealed that cell cycle-associated functions including cell division/proliferation were the most impacted pathways, which were negatively regulated by ozone exposure, an adverse effect that was associated with reduced bromo-deoxyuridine incorporation. These results demonstrate that acute ozone exposure alters cell proliferation in the developing neonatal lung through a global suppression of cell cycle function. PMID:24336422

  2. Improvement of cold resistance and performance of broilers by acute cold exposure during late embryogenesis.

    PubMed

    Shinder, D; Ruzal, M; Giloh, M; Druyan, S; Piestun, Y; Yahav, S

    2011-03-01

    The aim of this study was to fine-tune previous acute cold exposure treatments of broiler embryos during late embryogenesis to improve lifelong cold resistance and performance. Six hundred Cobb hatching eggs were incubated under standard conditions and then exposed to 3 treatments: control; cold treatment in which embryos were exposed to 15°C for 30 min on d 18 and 19 of incubation (30 × 2); and cold treatment similar to 30 × 2 but with 60-min exposures (60 × 2). Egg shell temperature (T(egg)) and heart rate (HR) were monitored pre- and posttreatment. Upon hatching, hatchability, body weight, and body temperature were recorded. From 14 to 35 d of age, three quarters of the chickens in each treatment were raised under ascites-inducing conditions (AIC) and the remaining birds were raised under standard brooding conditions (SBC). The T(egg) and HR decreased significantly in response to increased exposure time on d 18 of incubation. On d 19 of incubation, before the second cold exposure, the 30 × 2 group showed greater T(egg) and HR than the controls, and during the second exposure they maintained these parameters better than the 60 × 2 embryos. No treatment effect on hatchability was observed. At 35 d of age ascites incidence among 30 × 2 chickens under AIC was significantly less than that among the controls (P < 0.01), and body weight of these chickens under either SBC or AIC was significantly higher than that of the controls. Under SBC relative breast muscle weight was significantly higher in 60 × 2 chickens, whereas the relative heart weight was higher in both cold-treated groups than in the controls. It can be concluded that repeated short acute cold exposures during late embryogenesis significantly reduced ascites incidence and improved growth rate under either SBC or AIC. These results may be related to a prenatal epigenetic adaptation of the thermoregulatory and cardiovascular systems to low ambient temperature.

  3. Longitudinal Monitoring of Lung Injury in Children after Acute Chlorine Exposure in a Swimming Pool

    PubMed Central

    Bonetto, Gea; Corradi, Massimo; Carraro, Silvia; Zanconato, Stefania; Alinovi, Rossella; Folesani, Giuseppina; Da Dalt, Liviana; Mutti, Antonio; Baraldi, Eugenio

    2006-01-01

    Rationale: Acute exposure to chlorine gas results in respiratory impairment, but few data are available on the pathobiology of the underlying lung damage. Objectives: To assess lung function and potential lung damage pathways in the acute phase and longitudinally over a 15-mo follow-up after acute chlorine exposure. Methods: Ten previously healthy children were accidentally exposed to chlorine gas at a swimming pool because of an erroneous servicing procedure. The fraction of nitric oxide in exhaled air (FeNO), exhaled breath condensate compounds, and serum Clara cell–specific protein CC16 were repeatedly measured. Main results: In the acute phase, all patients had respiratory distress (one child required mechanical ventilation) and reduced lung function (median and interquartile range: FVC, 51 [43–60]% predicted; FEV1, 51 [46–60]% predicted). This was accompanied by low FeNO (4.7 [3.9–7.9] ppb), high exhaled breath condensate leukotriene B4 (LTB4) levels (24.4 [22.5–24.9] pg/ml), and increased serum CC16 levels (mean ± SEM, 23.4 ± 2.5 μg/L). Lung function returned to normal in 15 d (FVC, 97% predicted [82–108], and FEV1, 92% predicted [77–102]). FeNO reached normal values after 2 mo (12.6 [11.4–15] ppb), whereas LTB4 levels were still increased (12 [9.3–17.1] pg/ml). Conclusion: Children acutely exposed to chlorine in a swimming pool presented a substantial lung function impairment associated with biochemical exhaled breath alterations, represented mainly by an increase in LTB4 and a reduction in FeNO. Although lung function and FeNO improved within a few weeks, the increased levels of exhaled LTB4 persisted for several months. PMID:16763216

  4. Longitudinal monitoring of lung injury in children after acute chlorine exposure in a swimming pool.

    PubMed

    Bonetto, Gea; Corradi, Massimo; Carraro, Silvia; Zanconato, Stefania; Alinovi, Rossella; Folesani, Giuseppina; Da Dalt, Liviana; Mutti, Antonio; Baraldi, Eugenio

    2006-09-01

    Acute exposure to chlorine gas results in respiratory impairment, but few data are available on the pathobiology of the underlying lung damage. To assess lung function and potential lung damage pathways in the acute phase and longitudinally over a 15-mo follow-up after acute chlorine exposure. Ten previously healthy children were accidentally exposed to chlorine gas at a swimming pool because of an erroneous servicing procedure. The fraction of nitric oxide in exhaled air (Fe(NO)), exhaled breath condensate compounds, and serum Clara cell-specific protein CC16 were repeatedly measured. In the acute phase, all patients had respiratory distress (one child required mechanical ventilation) and reduced lung function (median and interquartile range: FVC, 51 [43-60]% predicted; FEV(1), 51 [46-60]% predicted). This was accompanied by low Fe(NO) (4.7 [3.9-7.9] ppb), high exhaled breath condensate leukotriene B(4) (LTB(4)) levels (24.4 [22.5-24.9] pg/ml), and increased serum CC16 levels (mean +/- SEM, 23.4 +/- 2.5 microg/L). Lung function returned to normal in 15 d (FVC, 97% predicted [82-108], and FEV(1), 92% predicted [77-102]). Fe(NO) reached normal values after 2 mo (12.6 [11.4-15] ppb), whereas LTB(4) levels were still increased (12 [9.3-17.1] pg/ml). Children acutely exposed to chlorine in a swimming pool presented a substantial lung function impairment associated with biochemical exhaled breath alterations, represented mainly by an increase in LTB(4) and a reduction in Fe(NO). Although lung function and Fe(NO) improved within a few weeks, the increased levels of exhaled LTB(4) persisted for several months.

  5. Estimated rate of fatal automobile accidents attributable to acute solvent exposure at low inhaled concentrations.

    PubMed

    Benignus, Vernon A; Bushnell, Philip J; Boyes, William K

    2011-12-01

    Acute solvent exposures may contribute to automobile accidents because they increase reaction time and decrease attention, in addition to impairing other behaviors. These effects resemble those of ethanol consumption, both with respect to behavioral effects and neurological mechanisms. These observations, along with the extensive data on the relationship between ethanol consumption and fatal automobile accidents, suggested a way to estimate the probability of fatal automobile accidents from solvent inhalation. The problem can be approached using the logic of the algebraic transitive postulate of equality: if A=B and B=C, then A=C. We first calculated a function describing the internal doses of solvent vapors that cause the same magnitude of behavioral impairment as ingestion of ethanol (A=B). Next, we fit a function to data from the literature describing the probability of fatal car crashes for a given internal dose of ethanol (B=C). Finally, we used these two functions to generate a third function to estimate the probability of a fatal car crash for any internal dose of organic solvent vapor (A=C). This latter function showed quantitatively (1) that the likelihood of a fatal car crash is increased by acute exposure to organic solvent vapors at concentrations less than 1.0 ppm, and (2) that this likelihood is similar in magnitude to the probability of developing leukemia from exposure to benzene. This approach could also be applied to other potentially adverse consequences of acute exposure to solvents (e.g., nonfatal car crashes, property damage, and workplace accidents), if appropriate data were available.

  6. Chromosomal Bands Affected by Acute Oil Exposure and DNA Repair Errors

    PubMed Central

    Zock, Jan-Paul; Giraldo, Jesús; Pozo-Rodríguez, Francisco; Espinosa, Ana; Rodríguez-Trigo, Gema; Verea, Hector; Castaño-Vinyals, Gemma; Gómez, Federico P.; Antó, Josep M.; Coll, Maria Dolors; Barberà, Joan Albert; Fuster, Carme

    2013-01-01

    Background In a previous study, we showed that individuals who had participated in oil clean-up tasks after the wreckage of the Prestige presented an increase of structural chromosomal alterations two years after the acute exposure had occurred. Other studies have also reported the presence of DNA damage during acute oil exposure, but little is known about the long term persistence of chromosomal alterations, which can be considered as a marker of cancer risk. Objectives We analyzed whether the breakpoints involved in chromosomal damage can help to assess the risk of cancer as well as to investigate their possible association with DNA repair efficiency. Methods Cytogenetic analyses were carried out on the same individuals of our previous study and DNA repair errors were assessed in cultures with aphidicolin. Results Three chromosomal bands, 2q21, 3q27 and 5q31, were most affected by acute oil exposure. The dysfunction in DNA repair mechanisms, expressed as chromosomal damage, was significantly higher in exposed-oil participants than in those not exposed (p= 0.016). Conclusion The present study shows that breaks in 2q21, 3q27 and 5q31 chromosomal bands, which are commonly involved in hematological cancer, could be considered useful genotoxic oil biomarkers. Moreover, breakages in these bands could induce chromosomal instability, which can explain the increased risk of cancer (leukemia and lymphomas) reported in chronically benzene-exposed individuals. In addition, it has been determined that the individuals who participated in clean-up of the oil spill presented an alteration of their DNA repair mechanisms two years after exposure. PMID:24303039

  7. Chromosomal bands affected by acute oil exposure and DNA repair errors.

    PubMed

    Monyarch, Gemma; de Castro Reis, Fernanda; Zock, Jan-Paul; Giraldo, Jesús; Pozo-Rodríguez, Francisco; Espinosa, Ana; Rodríguez-Trigo, Gema; Verea, Hector; Castaño-Vinyals, Gemma; Gómez, Federico P; Antó, Josep M; Coll, Maria Dolors; Barberà, Joan Albert; Fuster, Carme

    2013-01-01

    In a previous study, we showed that individuals who had participated in oil clean-up tasks after the wreckage of the Prestige presented an increase of structural chromosomal alterations two years after the acute exposure had occurred. Other studies have also reported the presence of DNA damage during acute oil exposure, but little is known about the long term persistence of chromosomal alterations, which can be considered as a marker of cancer risk. We analyzed whether the breakpoints involved in chromosomal damage can help to assess the risk of cancer as well as to investigate their possible association with DNA repair efficiency. Cytogenetic analyses were carried out on the same individuals of our previous study and DNA repair errors were assessed in cultures with aphidicolin. Three chromosomal bands, 2q21, 3q27 and 5q31, were most affected by acute oil exposure. The dysfunction in DNA repair mechanisms, expressed as chromosomal damage, was significantly higher in exposed-oil participants than in those not exposed (p= 0.016). The present study shows that breaks in 2q21, 3q27 and 5q31 chromosomal bands, which are commonly involved in hematological cancer, could be considered useful genotoxic oil biomarkers. Moreover, breakages in these bands could induce chromosomal instability, which can explain the increased risk of cancer (leukemia and lymphomas) reported in chronically benzene-exposed individuals. In addition, it has been determined that the individuals who participated in clean-up of the oil spill presented an alteration of their DNA repair mechanisms two years after exposure.

  8. A short latency between radiation exposure from nuclear plants and cancer in young children.

    PubMed

    Mangano, Joseph J

    2006-01-01

    Previous reports document a short latency of cancer onset in young children exposed to low doses of radioactivity. The standard mortality ratio (SMR) for cancer in children dying before age ten rose in the period 6-10 years after the Three Mile Island and Chernobyl accidents in populations most exposed to fallout. SMRs near most nuclear power plants were elevated 6-10 years after startup, particularly for leukemia. Cancer incidence in children under age ten living near New York and New Jersey nuclear plants increased 4-5 years after increases in average strontium-90 in baby teeth, and declined 4-5 years after Sr-90 averages dropped. The assumption that Sr-90 and childhood cancer are correlated is best supported for a supralinear dose-response, meaning the greatest per-dose risks are at the lowest doses. Findings document that the very young are especially susceptible to adverse effects of radiation exposure, even at relatively low doses.

  9. Acute Exposure to Ozone Exacerbates Acetaminophen-Induced Liver Injury in Mice

    PubMed Central

    Ibrahim Aibo, Daher; Birmingham, Neil P.; Lewandowski, Ryan; Maddox, Jane F.; Roth, Robert A.; Ganey, Patricia E.; Wagner, James G.; Harkema, Jack R.

    2010-01-01

    Ozone (O3), an oxidant air pollutant in photochemical smog, principally targets epithelial cells lining the respiratory tract. However, changes in gene expression have also been reported in livers of O3-exposed mice. The principal aim of the present study was to determine if acute exposure to environmentally relevant concentrations of O3 could cause exacerbation of drug-induced liver injury in mice. Overdose with acetaminophen (APAP) is the most common cause of drug-induced liver injury in developed countries. In the present study, we examined the hepatic effects of acute O3 exposure in mice pretreated with a hepatotoxic dose of APAP. C57BL/6 male mice were fasted overnight and then given APAP (300 mg/kg ip) or saline vehicle (0 mg/kg APAP). Two hours later, mice were exposed to 0, 0.25, or 0.5 ppm O3 for 6 h and then sacrificed 9 or 32 h after APAP administration (1 or 24 h after O3 exposure, respectively). Animals euthanized at 32 h were given 5-bromo-2-deoxyuridine 2 h before sacrifice to identify hepatocytes undergoing reparative DNA synthesis. Saline-treated mice exposed to either air or O3 had no liver injury. All APAP-treated mice developed marked centrilobular hepatocellular necrosis that increased in severity with time after APAP exposure. O3 exposure increased the severity of APAP-induced liver injury as indicated by an increase in necrotic hepatic tissue and plasma alanine aminotransferase activity. O3 also caused an increase in neutrophil accumulation in livers of APAP-treated animals. APAP induced a 10-fold increase in the number of bromodeoxyuridine-labeled hepatocytes that was markedly attenuated by O3 exposure. Gene expression analysis 9 h after APAP revealed differential expression of genes involved in inflammation, oxidative stress, and cellular regeneration in mice treated with APAP and O3 compared to APAP or O3 alone, providing some indications of the mechanisms behind the APAP and O3 potentiation. These results suggest that acute exposure to

  10. External radiation exposure and mortality in a cohort of French nuclear workers

    PubMed Central

    Telle‐Lamberton, M; Samson, E; Caër, S; Bergot, D; Bard, D; Bermann, F; MGélas, J; Giraud, J M; Hubert, P; Metz‐Flamant, C; Néron, M O; Quesne, B; Tirmarche, M; Hill, C

    2007-01-01

    Objective To analyse the effect of external radiation exposure on the mortality of French nuclear workers. Methods A cohort of 29 204 workers employed between 1950 and 1994 at the French Atomic Energy Commission (Commissariat à l'Energie Atomique (CEA)) or at the General Company of Nuclear Fuel (COmpagnie GEnérale des MAtières nucléaires (Cogema, now Areva NC)) was followed up for an average of 17.8 years. Standardised mortality ratios (SMRs) were computed with reference to French mortality rates. Dose‐effect relationship were analysed through trend tests and Poisson regression, with linear and log‐linear models. Results The mean exposure to X and gamma radiation was 8.3 mSv (16.9 mSv for exposed worker population). A total of 1842 deaths occurred between 1968 and 1994. A healthy worker effect was observed, the number of deaths in the cohort being 59% of the number expected from national mortality statistics. Among the 21 main cancer sites studied, a statistically significant excess was observed only for skin melanoma, and an excess of borderline statistical significance was observed for multiple myeloma. A dose‐effect relationship was observed for leukaemia after exclusion of chronic lymphoid leukaemia (CLL). The relative risk observed for non‐CLL leukaemia, n = 20, was 4.1 per 100 mSv (90% CI 1.4 to 12.2), linear model and 2.2 per 100 mSv (90% CI 1.2 to 3.3), log‐linear model. Significant dose‐effect relationship were also observed for causes of deaths associated with alcohol consumption: mouth and pharynx cancer, cirrhosis and alcoholic psychosis and external causes of death. Conclusion The risk of leukaemia increases with increasing exposure to external radiation; this is consistent with published results on other nuclear workers cohorts. PMID:17522135

  11. Assessment of Acute Trauma Exposure Response for FIRE-EMS Personnel.

    PubMed

    Hoffmann, Melissa C

    The purpose of this study was to develop an instrument that measures response to acute trauma exposure for firefighter and emergency medical service (EMS) personnel. The Acute Trauma Exposure Response Scale (ATERS) was intended to assess firefighter and EMS personnel response to acute trauma exposure from analytical, emotional, and physical perspectives. Data were analyzed on 97 firefighter and EMS personnel employed by a fire department in a mid-sized city in a western state. Principal component analysis (PCAR) using Winsteps software was employed to discover which variables in the set formed logical subsets that were independent of one another and included item analyses and assessment of internal consistency reliability (Cronbach's alpha). Rasch analysis included examination of dimensionality, person and item reliability, scale use and function, and construct validity including person-item fit statistics. Principal component analyses of residuals (PCAR) revealed three primary scales which were termed Emotional Psyche, Coping Ability, and Support Systems. Rasch analyses showed the ATERS performance to be acceptable as a new pilot measure with three distinct scales through reliability of person separation of .81 for Emotional Psyche, .66 for Coping Ability, and .63 for Support Systems, respectively (Nunnally and Bernstein, 1994; Carmines and Zeller, 1979; Devellis, 2012). The Rasch item reliability was .96 for Emotional Psyche, .95 for Coping Ability, and .97 for Support Systems. Response scale use and function was appropriate for each subscale. Validity was supported through PCA by evidence of good internal consistency. High item correlations indicated the items for each subscale were measuring a single construct. Likewise, Rasch analyses provided evidence of validity through an even spread of person ability to item difficulty for each of the three constructs. Good item fit provided proof of construct relevant variance and the absence of gaps along the

  12. Self-Reported Acute Health Effects and Exposure to Companion Animals.

    PubMed

    Krueger, W S; Hilborn, E D; Dufour, A P; Sams, E A; Wade, T J

    2016-06-01

    To understand the etiological burden of disease associated with acute health symptoms [e.g. gastrointestinal (GI), respiratory, dermatological], it is important to understand how common exposures influence these symptoms. Exposures to familiar and unfamiliar animals can result in a variety of health symptoms related to infection, irritation and allergy; however, few studies have examined this association in a large-scale cohort setting. Cross-sectional data collected from 50 507 participants in the United States enrolled from 2003 to 2009 were used to examine associations between animal contact and acute health symptoms during a 10-12 day period. Fixed-effects multivariable logistic regression estimated adjusted odds ratios (AORs) and 95% confident intervals (CI) for associations between animal exposures and outcomes of GI illness, respiratory illness and skin/eye symptoms. Two-thirds of the study population (63.2%) reported direct contact with animals, of which 7.7% had contact with at least one unfamiliar animal. Participants exposed to unfamiliar animals had significantly higher odds of self-reporting all three acute health symptoms, when compared to non-animal-exposed participants (GI: AOR = 1.4, CI = 1.2-1.7; respiratory: AOR = 1.5, CI = 1.2-1.8; and skin/eye: AOR = 1.9, CI = 1.6-2.3), as well as when compared to participants who only had contact with familiar animals. Specific contact with dogs, cats or pet birds was also significantly associated with at least one acute health symptom; AORs ranged from 1.1 to 1.5, when compared to participants not exposed to each animal. These results indicate that contact with animals, especially unfamiliar animals, was significantly associated with GI, respiratory and skin/eye symptoms. Such associations could be attributable to zoonotic infections and allergic reactions. Etiological models for acute health symptoms should consider contact with companion animals, particularly exposure to unfamiliar animals

  13. Acute respiratory toxicity following inhalation exposure to soman in guinea pigs

    SciTech Connect

    Perkins, Michael W.; Pierre, Zdenka; Rezk, Peter; Sabnekar, Praveena; Sciuto, Alfred M.; Nambiar, Madhusoodana P.

    2010-06-01

    Respiratory toxicity and lung injury following inhalation exposure to chemical warfare nerve agent soman was examined in guinea pigs without therapeutics to improve survival. A microinstillation inhalation exposure technique that aerosolizes the agent in the trachea was used to administer soman to anesthetized age and weight matched male guinea pigs. Animals were exposed to 280, 561, 841, and 1121 mg/m{sup 3} concentrations of soman for 4 min. Survival data showed that all saline controls and animals exposed to 280 and 561 mg/m{sup 3} soman survived, while animals exposed to 841, and 1121 mg/m{sup 3} resulted in 38% and 13% survival, respectively. The microinstillation inhalation exposure LCt{sub 50} for soman determined by probit analysis was 827.2 mg/m{sup 3}. A majority of the animals that died at 1121 mg/m{sup 3} developed seizures and died within 15-30 min post-exposure. There was a dose-dependent decrease in pulse rate and blood oxygen saturation of animals exposed to soman at 5-6.5 min post-exposure. Body weight loss increased with the dose of soman exposure. Bronchoalveolar lavage (BAL) fluid and blood acetylcholinesterase and butyrylcholinesterase activity was inhibited dose-dependently in soman treated groups at 24 h. BAL cells showed a dose-dependent increase in cell death and total cell counts following soman exposure. Edema by wet/dry weight ratio of the accessory lung lobe and trachea was increased slightly in soman exposed animals. An increase in total bronchoalveolar lavage fluid protein was observed in soman exposed animals at all doses. Differential cell counts of BAL and blood showed an increase in total lymphocyte counts and percentage of neutrophils. These results indicate that microinstillation inhalation exposure to soman causes respiratory toxicity and acute lung injury in guinea pigs.

  14. Assessing the Effects of Acute Amyloid β Oligomer Exposure in the Rat

    PubMed Central

    Wong, Ryan S.; Cechetto, David F.; Whitehead, Shawn N.

    2016-01-01

    Alzheimer’s disease (AD) is the most common form of dementia, yet there are no therapeutic treatments that can either cure or delay its onset. Currently, the pathogenesis of AD is still uncertain, especially with respect to how the disease develops from a normal healthy brain. Amyloid β oligomers (AβO) are highly neurotoxic proteins and are considered potential initiators to the pathogenesis of AD. Rat brains were exposed to AβO via bilateral intracerebroventricular injections. Rats were then euthanized at either 1, 3, 7 or 21-days post surgery. Rat behavioural testing was performed using the Morris water maze and open field tests. Post-mortem brain tissue was immunolabelled for Aβ, microglia, and cholinergic neurons. Rats exposed to AβO showed deficits in spatial learning and anxiety-like behaviour. Acute positive staining for Aβ was only observed in the corpus callosum surrounding the lateral ventricles. AβO exposed rat brains also showed a delayed increase in activated microglia within the corpus callosum and a decreased number of cholinergic neurons within the basal forebrain. Acute exposure to AβO resulted in mild learning and memory impairments with co-concomitant white matter pathology within the corpus callosum and cholinergic cell loss within the basal forebrain. Results suggest that acute exposure to AβO in the rat may be a useful tool in assessing the early phases for the pathogenesis of AD. PMID:27563885

  15. Hormetic Effects of Acute Methylmercury Exposure on Grp78 Expression in Rat Brain Cortex

    PubMed Central

    Zhang, Ye; Lu, Rongzhu; Liu, Wenshuai; Wu, Ying; Qian, Hai; Zhao, Xiaowu; Wang, Suhua; Xing, Guangwei; Yu, Feng; Aschner, Michael

    2013-01-01

    This study aims to explore the expression of GRP78, a marker of endoplasmic reticulum (ER) stress, in the cortex of rat brains acutely exposed to methylmercury (MeHg). Thirty Sprague-Dawley (SD) rats were randomly divided into six groups, and decapitated 6 hours (h) after intraperitoneal (i.p.) injection of MeHg (2, 4, 6, 8 or 10 mg/kg body weight) or normal saline. Protein and mRNA expression of Grp78 were detected by western blotting and real-time PCR, respectively. The results showed that a gradual increase in GRP78 protein expression was observed in the cortex of rats acutely exposed to MeHg (2, 4 or 6 mg/kg). Protein levels peaked in the 6 mg/kg group (p < 0.05 vs. controls), decreased in the 8 mg/kg group, and bottomed below the control level in the 10 mg/kg group. Parallel changes were noted for Grp78 mRNA expression. It may be implied that acute exposure to MeHg induced hormetic dose-dependent changes in Grp78 mRNA and protein expression, suggesting that activation of ER stress is involved in MeHg-induced neurotoxicity. Low level MeHg exposure may induce GRP78 protein expression to stimulate endogenous cytoprotective mechanisms. PMID:23549286

  16. Development of Toxicological Risk Assessment Models for Acute and Chronic Exposure to Pollutants

    PubMed Central

    Reichwaldt, Elke S.; Stone, Daniel; Barrington, Dani J.; Sinang, Som C.; Ghadouani, Anas

    2016-01-01

    Alert level frameworks advise agencies on a sequence of monitoring and management actions, and are implemented so as to reduce the risk of the public coming into contact with hazardous substances. Their effectiveness relies on the detection of the hazard, but with many systems not receiving any regular monitoring, pollution events often go undetected. We developed toxicological risk assessment models for acute and chronic exposure to pollutants that incorporate the probabilities that the public will come into contact with undetected pollution events, to identify the level of risk a system poses in regards to the pollutant. As a proof of concept, we successfully demonstrated that the models could be applied to determine probabilities of acute and chronic illness types related to recreational activities in waterbodies containing cyanotoxins. Using the acute model, we identified lakes that present a ‘high’ risk to develop Day Away From Work illness, and lakes that present a ‘low’ or ‘medium’ risk to develop First Aid Cases when used for swimming. The developed risk models succeeded in categorising lakes according to their risk level to the public in an objective way. Modelling by how much the probability of public exposure has to decrease to lower the risks to acceptable levels will enable authorities to identify suitable control measures and monitoring strategies. We suggest broadening the application of these models to other contaminants. PMID:27589798

  17. Development of Toxicological Risk Assessment Models for Acute and Chronic Exposure to Pollutants.

    PubMed

    Reichwaldt, Elke S; Stone, Daniel; Barrington, Dani J; Sinang, Som C; Ghadouani, Anas

    2016-08-31

    Alert level frameworks advise agencies on a sequence of monitoring and management actions, and are implemented so as to reduce the risk of the public coming into contact with hazardous substances. Their effectiveness relies on the detection of the hazard, but with many systems not receiving any regular monitoring, pollution events often go undetected. We developed toxicological risk assessment models for acute and chronic exposure to pollutants that incorporate the probabilities that the public will come into contact with undetected pollution events, to identify the level of risk a system poses in regards to the pollutant. As a proof of concept, we successfully demonstrated that the models could be applied to determine probabilities of acute and chronic illness types related to recreational activities in waterbodies containing cyanotoxins. Using the acute model, we identified lakes that present a 'high' risk to develop Day Away From Work illness, and lakes that present a 'low' or 'medium' risk to develop First Aid Cases when used for swimming. The developed risk models succeeded in categorising lakes according to their risk level to the public in an objective way. Modelling by how much the probability of public exposure has to decrease to lower the risks to acceptable levels will enable authorities to identify suitable control measures and monitoring strategies. We suggest broadening the application of these models to other contaminants.

  18. Arc-Heater Facility for Hot Hydrogen Exposure of Nuclear Thermal Rocket Materials

    NASA Technical Reports Server (NTRS)

    Litchford, Ron J.; Foote, John P.; Wang,Ten-See; Hickman, Robert; Panda, Binayak; Dobson, Chris; Osborne, Robin; Clifton, Scooter

    2006-01-01

    A hyper-thermal environment simulator is described for hot hydrogen exposure of nuclear thermal rocket material specimens and component development. This newly established testing capability uses a high-power, multi-gas, segmented arc-heater to produce high-temperature pressurized hydrogen flows representative of practical reactor core environments and is intended to serve. as a low cost test facility for the purpose of investigating and characterizing candidate fueUstructura1 materials and improving associated processing/fabrication techniques. Design and development efforts are thoroughly summarized, including thermal hydraulics analysis and simulation results, and facility operating characteristics are reported, as determined from a series of baseline performance mapping tests.

  19. An update on radioactive release and exposures after the Fukushima Dai-ichi nuclear disaster.

    PubMed

    McLaughlin, P D; Jones, B; Maher, M M

    2012-09-01

    On 11 March 2011, the Richter scale 0.9-magnitude Tokohu earthquake and tsunami struck the northeast coast of Japan, resulting in widespread injury and loss of life. Compounding this tragic loss of life, a series of equipment and structural failures at the Fukushima Dai-ichi nuclear power plant (FDNP) resulted in the release of many volatile radioisotopes into the atmosphere. In this update, we detail currently available evidence about the nature of immediate radioactive exposure to FDNP workers and the general population. We contrast the nature of the radioactive exposure at FDNP with that which occurred at the Chernobyl power plant 25 years previously. Prediction of the exact health effects related to the FDNP release is difficult at present and this disaster provides the scientific community with a challenge to help those involved and to continue research that will improve our understanding of the potential complications of radionuclide fallout.

  20. Dynamic friction and wear of a solid film lubricant during radiation exposure in a nuclear reactor

    NASA Technical Reports Server (NTRS)

    Jacobson, T. P.

    1972-01-01

    The effect of nuclear reactor radiation on the performance of a solid film lubricant was studied. The film consisted of molybdenum disulfide and graphite in a sodium silicate binder. Radiation levels of fast neutrons (E or = 1 MeV) were fluxed up to 3.5 times 10 to the 12th power n/sq cm-sec (intensity) and fluences up to 2 times 10 to the 18th power n/sq cm (total exposure). Coating wear lives were much shorter and friction coefficients higher in a high flux region of the reactor than in a low flux region. The amount of total exposure did not affect lubrication behavior as severely as the radiation intensity during sliding.

  1. An update on radioactive release and exposures after the Fukushima Dai-ichi nuclear disaster

    PubMed Central

    Mclaughlin, P D; Jones, B; Maher, M M

    2012-01-01

    On 11 March 2011, the Richter scale 0.9-magnitude Tokohu earthquake and tsunami struck the northeast coast of Japan, resulting in widespread injury and loss of life. Compounding this tragic loss of life, a series of equipment and structural failures at the Fukushima Dai-ichi nuclear power plant (FDNP) resulted in the release of many volatile radioisotopes into the atmosphere. In this update, we detail currently available evidence about the nature of immediate radioactive exposure to FDNP workers and the general population. We contrast the nature of the radioactive exposure at FDNP with that which occurred at the Chernobyl power plant 25 years previously. Prediction of the exact health effects related to the FDNP release is difficult at present and this disaster provides the scientific community with a challenge to help those involved and to continue research that will improve our understanding of the potential complications of radionuclide fallout. PMID:22919005

  2. Cytoplasmic proliferating cell nuclear antigen connects glycolysis and cell survival in acute myeloid leukemia

    PubMed Central

    Ohayon, Delphine; De Chiara, Alessia; Chapuis, Nicolas; Candalh, Céline; Mocek, Julie; Ribeil, Jean-Antoine; Haddaoui, Lamya; Ifrah, Norbert; Hermine, Olivier; Bouillaud, Frédéric; Frachet, Philippe; Bouscary, Didier; Witko-Sarsat, Véronique

    2016-01-01

    Cytosolic proliferating cell nuclear antigen (PCNA), a scaffolding protein involved in DNA replication, has been described as a key element in survival of mature neutrophil granulocytes, which are non-proliferating cells. Herein, we demonstrated an active export of PCNA involved in cell survival and chemotherapy resistance. Notably, daunorubicin-resistant HL-60 cells (HL-60R) have a prominent cytosolic PCNA localization due to increased nuclear export compared to daunorubicin-sensitive HL-60 cells (HL-60S). By interacting with nicotinamide phosphoribosyltransferase (NAMPT), a protein involved in NAD biosynthesis, PCNA coordinates glycolysis and survival, especially in HL-60R cells. These cells showed a dramatic increase in intracellular NAD+ concentration as well as glycolysis including increased expression and activity of hexokinase 1 and increased lactate production. Furthermore, this functional activity of cytoplasmic PCNA was also demonstrated in patients with acute myeloid leukemia (AML). Our data uncover a novel pathway of nuclear export of PCNA that drives cell survival by increasing metabolism flux. PMID:27759041

  3. Acute pulmonary toxicity following inhalation exposure to aerosolized VX in anesthetized rats.

    PubMed

    Peng, Xinqi; Perkins, Michael W; Simons, Jannitt; Witriol, Alicia M; Rodriguez, Ashley M; Benjamin, Brittany M; Devorak, Jennifer; Sciuto, Alfred M

    2014-06-01

    This study evaluated acute toxicity and pulmonary injury in rats at 3, 6 and 24 h after an inhalation exposure to aerosolized O-ethyl S-[2-(diisopropylamino)ethyl] methylphosphonothioate (VX). Anesthetized male Sprague-Dawley rats (250-300 g) were incubated with a glass endotracheal tube and exposed to saline or VX (171, 343 and 514 mg×min/m³ or 0.2, 0.5 and 0.8 LCt₅₀, respectively) for 10 min. VX was delivered by a small animal ventilator at a volume of 2.5 ml × 70 breaths/minute. All VX-exposed animals experienced a significant loss in percentage body weight at 3, 6, and 24 h post-exposure. In comparison to controls, animals exposed to 514 mg×min/m³ of VX had significant increases in bronchoalveolar lavage (BAL) protein concentrations at 6 and 24 h post-exposure. Blood acetylcholinesterase (AChE) activity was inhibited dose dependently at each of the times points for all VX-exposed groups. AChE activity in lung homogenates was significantly inhibited in all VX-exposed groups at each time point. All VX-exposed animals assessed at 20 min and 3, 6 and 24 h post-exposure showed increases in lung resistance, which was prominent at 20 min and 3 h post-exposure. Histopathologic evaluation of lung tissue of the 514 mg×min/m³ VX-exposed animals at 3, 6 and 24 h indicated morphological changes, including perivascular inflammation, alveolar exudate and histiocytosis, alveolar septal inflammation and edema, alveolar epithelial necrosis, and bronchiolar inflammatory infiltrates, in comparison to controls. These results suggest that aerosolization of the highly toxic, persistent chemical warfare nerve agent VX results in acute pulmonary toxicity and lung injury in rats.

  4. Acute Infections and Environmental Exposure to Organochlorines in Inuit Infants from Nunavik

    PubMed Central

    Dallaire, Frédéric; Dewailly, Éric; Muckle, Gina; Vézina, Carole; Jacobson, Sandra W.; Jacobson, Joseph L.; Ayotte, Pierre

    2004-01-01

    The Inuit population of Nunavik (Canada) is exposed to immunotoxic organochlorines (OCs) mainly through the consumption of fish and marine mammal fat. We investigated the effect of perinatal exposure to polychlorinated biphenyls (PCBs) and dichlorodiphenyldichloroethylene (DDE) on the incidence of acute infections in Inuit infants. We reviewed the medical charts of a cohort of 199 Inuit infants during the first 12 months of life and evaluated the incidence rates of upper and lower respiratory tract infections (URTI and LRTIs, respectively), otitis media, and gastrointestinal (GI) infections. Maternal plasma during delivery and infant plasma at 7 months of age were sampled and assayed for PCBs and DDE. Compared to rates for infants in the first quartile of exposure to PCBs (least exposed), adjusted rate ratios for infants in higher quartiles ranged between 1.09 and 1.32 for URTIs, 0.99 and 1.39 for otitis, 1.52 and 1.89 for GI infections, and 1.16 and 1.68 for LRTIs during the first 6 months of follow-up. For all infections combined, the rate ratios ranged from 1.17 to 1.27. The effect size was similar for DDE exposure but was lower for the full 12-month follow-up. Globally, most rate ratios were > 1.0, but few were statistically significant (p < 0.05). No association was found when postnatal exposure was considered. These results show a possible association between prenatal exposure to OCs and acute infections early in life in this Inuit population. PMID:15471725

  5. Acute Exposure to Pacific Ciguatoxin Reduces Electroencephalogram Activity and Disrupts Neurotransmitter Metabolic Pathways in Motor Cortex.

    PubMed

    Kumar, Gajendra; Au, Ngan Pan Bennett; Lei, Elva Ngai Yu; Mak, Yim Ling; Chan, Leanne Lai Hang; Lam, Michael Hon Wah; Chan, Leo Lai; Lam, Paul Kwan Sing; Ma, Chi Him Eddie

    2016-09-10

    Ciguatera fish poisoning (CFP) is a common human food poisoning caused by consumption of ciguatoxin (CTX)-contaminated fish affecting over 50,000 people worldwide each year. CTXs are classified depending on their origin from the Pacific (P-CTXs), Indian Ocean (I-CTXs), and Caribbean (C-CTXs). P-CTX-1 is the most toxic CTX known and the major source of CFP causing an array of neurological symptoms. Neurological symptoms in some CFP patients last for several months or years; however, the underlying electrophysiological properties of acute exposure to CTXs remain unknown. Here, we used CTX purified from ciguatera fish sourced in the Pacific Ocean (P-CTX-1). Delta and theta electroencephalography (EEG) activity was reduced remarkably in 2 h and returned to normal in 6 h after a single exposure. However, second exposure to P-CTX-1 induced not only a further reduction in EEG activities but also a 2-week delay in returning to baseline EEG values. Ciguatoxicity was detected in the brain hours after the first and second exposure by mouse neuroblastoma assay. The spontaneous firing rate of single motor cortex neuron was reduced significantly measured by single-unit recording with high spatial resolution. Expression profile study of neurotransmitters using targeted profiling approach based on liquid chromatography-tandem mass spectrometry revealed an imbalance between excitatory and inhibitory neurotransmitters in the motor cortex. Our study provides a possible link between the brain oscillations and neurotransmitter release after acute exposure to P-CTX-1. Identification of EEG signatures and major metabolic pathways affected by P-CTX-1 provides new insight into potential biomarker development and therapeutic interventions.

  6. Neurotoxicity of FireMaster 550® in zebrafish (Danio rerio): Chronic developmental and acute adolescent exposures

    PubMed Central

    Bailey, J.M.; Levin, E.D.

    2015-01-01

    BACKGROUND FireMaster® 550 (FM 550) is the second most commonly used flame retardant (FR) product in consumer goods and has been detected in household dust samples. However, neurobehavioral effects associated with exposure have not been characterized in detail. We investigated the behavioral effects of FM 550 in zebrafish to facilitate the integration of the cellular and molecular effects of FM 550 with its behavioral consequences. The effects of developmental FM 550 exposure on zebrafish larvae swimming shortly after the end of exposure as well as the persisting effects of this exposure on adolescent behavior were studied. In addition, the acute effects of FM 550 on behavior with exposure during adolescence in zebrafish were studied. METHODS Developmental exposure to 0, 0.01, 0.1 or 1 mg/L of FM 550 via immersion spanned 0–5 days post fertilization, with larval testing on day 6 and adolescent testing on days 40–45. Acute adolescent (45 dpf) exposure was to 0, 1.0 or 3.0 mg/L of FM 550 via immersion, for 24 hrs, with testing 2 hr or 1 week later. The vehicle condition was colony tank water with .0004% (developmental) or .0012% (adolescent) DMSO. Zebrafish behavior was characterized across several domains including learning, social affiliation, sensorimotor function, predator escape, and novel environment exploration. RESULTS Persisting effects of developmental FM 550 exposure included a significant (p < 0.01) reduction in social behavior among all dose groups. Acute FM550 exposure during adolescence caused hypoactivity and reduced social behavior (p’s < 0.05) when the fish were tested 2 hr after exposure. These effects were attenuated at the 1 week post exposure testing point. DISCUSSION Taken together, these data indicate that FM 550 may cause persisting neurobehavioral alterations to social behavior in the absence of perturbations along other behavioral domains and that developmental exposure is more costly to the organism than acute adolescent exposure

  7. Geographical distribution of acute symptoms after a train collision involving epichlorohydrin exposure.

    PubMed

    Radon, Katja; Rosenberger, Armin; Ehrenstein, Vera; Hoopmann, Michael; Basting, Imke; Tödt, Helga; Reichert, Jörg; Dressel, Holger; Schmid, Martina; Suchenwirth, Roland; Nowak, Dennis

    2006-09-01

    In September 2002, two freight trains collided in a northern German town. The inhabitants were potentially exposed to the probable human carcinogen epichlorohydrin. As no objective data on the level of exposure were available, we aimed to assess the geographical distribution of acute symptoms among local residents and subjects occupationally involved in the accident (e.g., firemen). A random sample of 932 adult local residents and 342 occupationally involved subjects were invited to answer a mail-in questionnaire. The main outcome measures were self-reported acute symptoms potentially associated with combustion products (e.g., irritation of the eyes, nose, or throat) and stress-related nonspecific symptoms. The main location during the first 26 h after the accident served as exposure proxy. For occupationally involved subjects, the time spent at the accident site was also used. The overall prevalence of symptoms potentially associated with combustion products was 9.8% for residents and 25.4% for occupationally involved subjects. After adjustment, subjects whose main location was close to the accident site had an increased risk for such symptoms. Among occupationally involved subjects the risk increased with duration at the accident site. Neither main location nor time at the accident site was significantly associated with non-specific symptoms. We could provide an example for designing and carrying out an epidemiologic study shortly after a local accident with potential public health impact. We could define parts of the population at increased risk for symptoms potentially specific for the exposure under study.

  8. Acute exposure to DE-71: effects on locomotor behavior and developmental neurotoxicity in zebrafish larvae.

    PubMed

    Chen, Lianguo; Huang, Changjiang; Hu, Chenyan; Yu, Ke; Yang, Lihua; Zhou, Bingsheng

    2012-10-01

    The aim of the present study was to investigate the acute developmental neurotoxicity of polybrominated diphenyl ethers (PBDEs) in zebrafish larvae. From 2 to 120 h postfertilization zebrafish embryos were exposed to DE-71 (0, 31.0, 68.7, and 227.6 µg/L). The authors studied the locomotor behavior of larvae, involvement of the cholinergic system, and selected gene and protein expressions in the central nervous system. The results showed that low DE-71 concentration caused hyperactivity, whereas higher concentrations decreased activity during the dark period. During the light period, larval activity was significantly reduced in a concentration-dependent manner. In the cholinergic system, acetylcholinesterase activity significantly increased (10.7 and 12.4%) in the 68.7 and 227.6 µg/L exposure groups, respectively, and acetylcholine concentration accordingly decreased (60.5%) in the 227.6 µg/L exposure group. The mRNA expressions of genes encoding myelin basic protein, neuron microtubule protein (α1-tubulin), and sonic hedgehog a were significantly downregulated. Western blotting assay demonstrated that the protein concentration of α1-tubulin was also decreased. Overall, the present study demonstrated that acute exposure to PBDEs can disrupt the neurobehavior of zebrafish larvae and affect cholinergic neurotransmission and neuron development.

  9. Persistent Adult Zebrafish Behavioral Deficits Results from Acute Embryonic Exposure to Gold Nanoparticles

    PubMed Central

    Truong, Lisa; Saili, Katerine S.; Miller, John M.; Hutchison, James E.; Tanguay, Robert L.

    2011-01-01

    As the number of products containing nanomaterials increase, human exposure to nanoparticles (NPs) is unavoidable. Presently, few studies focus on the potential long-term consequences of developmental NP exposure. In this study, zebrafish embryos were acutely exposed to three gold NPs that possess functional groups with differing surface charge. Embryos were exposed to 50 μg/mL of 1.5 nm gold nanoparticles (AuNPs) possessing negatively charged 2-mercaptoethanesulfonic acid (MES) or neutral 2-(2-(2-mercaptoethoxy)ethoxy)ethanol (MEEE) ligands or 10 μg/mL of the AuNPs possessing positively charged trimethylammoniumethanethiol (TMAT). Both MES- and TMAT-AuNP exposed embryos exhibited hypo-locomotor activity, while those exposed to MEEE-AuNPs did not. A subset of embryos that were exposed to 1.5 nm MES- and TMAT-AuNPs during development from 6–120 hours post fertilization were raised to adulthood. Behavioral abnormalities and the number of survivors into adulthood were evaluated at 122 days post fertilization. We found that both treatments induced abnormal startle behavior following a tap stimulus. However, the MES-AuNPs exposed group also exhibited abnormal adult behavior in the light and had a lower survivorship into adulthood. This study demonstrates that acute, developmental exposure to 1.5 nm MES- and TMAT- AuNPs, two NPs differing only in the functional group, affects larval behavior, with behavioral effects persisting into adulthood. PMID:21946249

  10. Acute toxicity effects of Prunus avium fruit extract and selection of optimum dose against radiation exposure.

    PubMed

    Sisodia, Rashmi; Sharma, K; Singh, Smita

    2009-01-01

    The objective of the study was to evaluate the acute toxicity of different doses of the methanolic extract of the fruit pulp of Prunus avium (family Rosaceae), which is used ethno-medicinally for the treatment of various diseases, and to find out the optimal dose of Prunus avium extract against 10 Gy gamma-radiation exposure. To test acute toxicity in mice, different doses of PAE (Prunus avium fruit extract) were given orally for 15 consecutive days, after which the animals were observed for another 15 days; the LD50/15 of the methanolic extract was calculated to be 4.947 gm/kg body weight (b.wt). In optimum dose selection against radiation exposure, oral administration of 450 mg/kg b.wt/d of PAE for 15 consecutive days before exposure to 10 Gy of gamma-radiation was found to afford maximum protection in terms of body weight and survivability of the mice in comparison to other doses.

  11. Dexamethasone exposure and asparaginase antibodies affect relapse risk in acute lymphoblastic leukemia.

    PubMed

    Kawedia, Jitesh D; Liu, Chengcheng; Pei, Deqing; Cheng, Cheng; Fernandez, Christian A; Howard, Scott C; Campana, Dario; Panetta, John C; Bowman, W Paul; Evans, William E; Pui, Ching-Hon; Relling, Mary V

    2012-02-16

    We have previously hypothesized that higher systemic exposure to asparaginase may cause increased exposure to dexamethasone, both critical chemotherapeutic agents for acute lymphoblastic leukemia. Whether interpatient pharmaco-kinetic differences in dexamethasone contribute to relapse risk has never been studied. The impact of plasma clearance of dexamethasone and anti-asparaginase antibody levels on risk of relapse was assessed in 410 children who were treated on a front-line clinical trial for acute lymphoblastic leukemia and were evaluable for all pharmacologic measures, using multivariate analyses, adjusting for standard clinical and biologic prognostic factors. Dexamethasone clearance (mean ± SD) was higher (P = 3 × 10(-8)) in patients whose sera was positive (17.7 ± 18.6 L/h per m(2)) versus nega-tive (10.6 ± 5.99 L/h per m(2)) for anti-asparaginase antibodies. In multivariate analyses, higher dexamethasone clearance was associated with a higher risk of any relapse (P = .01) and of central nervous system relapse (P = .014). Central nervous system relapse was also more common in patients with anti-asparaginase antibodies (P = .019). In conclusion, systemic clearance of dexamethasone is higher in patients with anti-asparaginase antibodies. Lower exposure to both drugs was associated with an increased risk of relapse.

  12. Indoor residential radon exposure and risk of childhood acute myeloid leukaemia

    PubMed Central

    Steinbuch, M; Weinberg, C R; Buckley, J D; Robison, L L; Sandler, D P

    1999-01-01

    Exposure to radon has been identified as a risk factor for lung cancer in uranium miners, but evidence of adverse health effects due to indoor radon exposure is inconsistent. Ecological studies have suggested a correlation between indoor radon levels and leukaemia incidence. We evaluated the risk associated with indoor residential radon exposure within a larger interview-based case–control study of risk factors for childhood acute myeloid leukaemia (AML). A total of 173 cases and 254 controls met the eligibility criteria, and information was collected through telephone interviews with parents and analysis of alpha-track radon detectors placed in the home for a period of 1 year. No association was observed between radon exposure and risk of AML, with adjusted odds ratios of 1.2 (95% confidence interval (CI) 0.7–1.8) for 37–100 Bq m–3 and 1.1 (95% CI 0.6–2.0) for > 100 Bq m–3 compared with < 37 Bq m–3. Although there was an inverse association between radon level and AML risk among children < 2 years at diagnosis, among children ≥2 years, AML risk was increased among those with higher radon exposure. The observed association after age 2 is most likely due to chance. Overall, there was no association between residential radon and risk of childhood AML. © 1999 Cancer Research Campaign PMID:10555766

  13. Effects of acute low-level microwaves on pentobarbital-induced hypothermia depend on exposure orientation

    SciTech Connect

    Lai, H.; Horita, A.; Chou, C.K.; Guy, A.W.

    1984-01-01

    Two series of experiments were performed to study the effects of acute exposure (45 min) to 2,450-MHz circularly polarized, pulsed microwaves (1 mW/cm2, 2-mus pulses, 500 pps, specific absorption rate (SAR) 0.6 W/kg) on the actions of pentobarbital in the rat. In the first experiment, rats were irradiated with microwaves and then immediately injected with pentobarbital. Microwave exposure did not significantly affect the extent of the pentobarbital-induced fall in colonic temperature. However, the rate of recovery from the hypothermia was significantly slower in the microwave-irradiated rats and they also took a significantly longer time to regain their righting reflex. In a second experiment, rats were first anesthetized with pentobarbital and then exposed to microwaves with their heads either pointing toward the source of microwaves (anterior exposure) or pointing away (posterior exposure). Microwave radiation significantly retarded the pentobarbital-induced fall in colonic temperature regardless of the orientation of exposure. However, the recovery from hypothermia was significantly faster in posterior-exposed animals compared to those of the anterior-exposed and sham-irradiated animals. Furthermore, the posterior-exposed rats took a significantly shorter time to regain their righting reflex than both the anterior-exposed and sham-irradiated animals.

  14. Temporal Changes in Rat Liver Gene Expression after Acute Cadmium and Chromium Exposure

    PubMed Central

    Madejczyk, Michael S.; Baer, Christine E.; Dennis, William E.; Minarchick, Valerie C.; Leonard, Stephen S.; Jackson, David A.; Stallings, Jonathan D.; Lewis, John A.

    2015-01-01

    U.S. Service Members and civilians are at risk of exposure to a variety of environmental health hazards throughout their normal duty activities and in industrial occupations. Metals are widely used in large quantities in a number of industrial processes and are a common environmental toxicant, which increases the possibility of being exposed at toxic levels. While metal toxicity has been widely studied, the exact mechanisms of toxicity remain unclear. In order to further elucidate these mechanisms and identify candidate biomarkers, rats were exposed via a single intraperitoneal injection to three concentrations of CdCl2 and Na2Cr2O7, with livers harvested at 1, 3, or 7 days after exposure. Cd and Cr accumulated in the liver at 1 day post exposure. Cd levels remained elevated over the length of the experiment, while Cr levels declined. Metal exposures induced ROS, including hydroxyl radical (•OH), resulting in DNA strand breaks and lipid peroxidation. Interestingly, ROS and cellular damage appeared to increase with time post-exposure in both metals, despite declines in Cr levels. Differentially expressed genes were identified via microarray analysis. Both metals perturbed gene expression in pathways related to oxidative stress, metabolism, DNA damage, cell cycle, and inflammatory response. This work provides insight into the temporal effects and mechanistic pathways involved in acute metal intoxication, leading to the identification of candidate biomarkers. PMID:25993096

  15. Indoor residential radon exposure and risk of childhood acute myeloid leukaemia.

    PubMed

    Steinbuch, M; Weinberg, C R; Buckley, J D; Robison, L L; Sandler, D P

    1999-11-01

    Exposure to radon has been identified as a risk factor for lung cancer in uranium miners, but evidence of adverse health effects due to indoor radon exposure is inconsistent. Ecological studies have suggested a correlation between indoor radon levels and leukaemia incidence. We evaluated the risk associated with indoor residential radon exposure within a larger interview-based case-control study of risk factors for childhood acute myeloid leukaemia (AML). A total of 173 cases and 254 controls met the eligibility criteria, and information was collected through telephone interviews with parents and analysis of alpha-track radon detectors placed in the home for a period of 1 year. No association was observed between radon exposure and risk of AML, with adjusted odds ratios of 1.2 (95% confidence interval (CI) 0.7-1.8) for 37-100 Bq m(-3) and 1.1 (95% CI 0.6-2.0) for > 100 Bq m(-3) compared with < 37 Bq m(-3). Although there was an inverse association between radon level and AML risk among children < 2 years at diagnosis, among children > or = 2 years, AML risk was increased among those with higher radon exposure. The observed association after age 2 is most likely due to chance. Overall, there was no association between residential radon and risk of childhood AML.

  16. Acute changes in sputum IL-10 following underground exposure to diesel exhaust.

    PubMed

    Burgess, Jefferey L; Fleming, Joy E; Mulenga, Emmanuel M; Josyula, Arun; Hysong, Tracy A; Joggerst, Philip J; Kurzius-Spencer, Margaret; Miller, Hugh B

    2007-01-01

    Although exposure to diesel exhaust has been linked with adverse health effects, little is known about the acute effects of exposure in the underground workplace. Cross-shift spirometry and sputum induction were completed on twelve subjects associated with comminuted rock removal (mucking) operations in an underground copper mine using diesel powered and pneumatic equipment on separate days, and sputum collected on a baseline non-exposure day as well. For diesel operations, elemental carbon exposure averaged 538 +/- 512 microg/m(3) during the 1-2 hour operations. Sputum interleukin-10 decreased with diesel exhaust using one ELISA assay (3.69 v. 2.32 pg/ml, p = 0.015), but increased when measured with a different ELISA kit (0.18 v. 0.59 pg/ml, p = 0.019), consistent with an overall decline in IL-10 protein concentration but an increase in the biologically active form. Sputum interleukin-6 decreased with exposure to diesel exhaust, although this change lost statistical significance when restricted to non-smokers. There were no significant changes in spirometry, interleukins 1beta, 4, and 8, tumor necrosis factor alpha or 8-hydroxy-2'-deoxyguanosine. High levels of diesel exhaust can result in rapid changes in sputum IL-10, suggesting possible protein modification.

  17. Acute Exposure to Crystalline Silica Reduces Macrophage Activation in Response to Bacterial Lipoproteins

    PubMed Central

    Beamer, Gillian L.; Seaver, Benjamin P.; Jessop, Forrest; Shepherd, David M.; Beamer, Celine A.

    2016-01-01

    Numerous studies have examined the relationship between alveolar macrophages (AMs) and crystalline silica (SiO2) using in vitro and in vivo immunotoxicity models; however, exactly how exposure to SiO2 alters the functionality of AM and the potential consequences for immunity to respiratory pathogens remains largely unknown. Because recognition and clearance of inhaled particulates and microbes are largely mediated by pattern recognition receptors (PRRs) on the surface of AM, we hypothesized that exposure to SiO2 limits the ability of AM to respond to bacterial challenge by altering PRR expression. Alveolar and bone marrow-derived macrophages downregulate TLR2 expression following acute SiO2 exposure (e.g., 4 h). Interestingly, these responses were dependent on interactions between SiO2 and the class A scavenger receptor CD204, but not MARCO. Furthermore, SiO2 exposure decreased uptake of fluorescently labeled Pam2CSK4 and Pam3CSK4, resulting in reduced secretion of IL-1β, but not IL-6. Collectively, our data suggest that SiO2 exposure alters AM phenotype, which in turn affects their ability to uptake and respond to bacterial lipoproteins. PMID:26913035

  18. Acute pulmonary effects of nitrogen dioxide exposure during exercise in competitive athletes

    SciTech Connect

    Kim, S.U.; Koenig, J.Q.; Pierson, W.E.; Hanley, Q.S. )

    1991-04-01

    The acute pulmonary responses of athletes after short-term exposure to ambient concentrations of NO{sub 2} during heavy exercise have been examined. Intercollegiate male athletes were screened for history of cardiac disease, respiratory disease, allergic conditions and extensive exposure to pollutants. After completion of serum IgE level determination, exercise tolerance test and methacholine challenge test with normal results, nine healthy subjects 18 to 23 years of age were exposed to filtered air and to 0.18 and 0.30 ppm NO{sub 2} for 30 min on different days while exercising on a treadmill. Pulmonary function parameters were measured before and after each exposure. In this study, no statistically significant changes were observed in FEV1, RT PEFR, and Vmax50% after exposure to 0.18 and 0.30 ppm NO{sub 2}. For these selected healthy athletes, short-term exposure to ambient NO{sub 2} levels during heavy exercise does not affect adversely the pulmonary function.

  19. Acute and subacute exposure to malathion impairs aversive but not non-associative memory in rats.

    PubMed

    Valvassori, Samira S; Fortunato, Jucélia J; Gomes, Karin M; Réus, Gislaine Z; Martins, Márcio R; Gavioli, Elaine C; Schetinger, Maria Rosa C; Dal-Pizzol, Felipe; Quevedo, João

    2007-07-01

    Malathion [S-(1,2-dicarbethoxy) ethyl-0,0-dimethyl-phosphorodithioate] is an organophosphorus compound that is widely used as pesticide especially in developing countries. This pesticide affects the central nervous system by inhibiting acetylcholinesterase, leading to an increase of acetylcholine in the synaptic cleft, and subsequent activation of cholinergic muscarinic and nicotinic receptors. In humans, intoxication with organophosphates causes a wide range of neurological symptoms, including memory deficits. The present study was aimed to investigate the effects of the acute (1 h prior the test) and subacute (once a day for 28 days) exposure to malathion at doses of 25, 50, 100 and 150 mg/kg in rats tested in the step-down inhibitory avoidance task, open-field habituation and elevated plus-maze tests. Interestingly, the acute and subacute treatment with malathion impaired aversive-memory in the step-down inhibitory avoidance task, but did not alter the animal performance in the elevated plus-maze and in the habituation to the open-field tests, and neither modified spontaneous locomotion. The activity of acetylcholinesterase enzyme was significantly reduced after subacute, but not acute, treatment with malathion (25, 100 and 150 mg/kg). Our results suggest that malathion impairs aversive-memory retention but not non-associative memory, without affecting anxiety-related behaviors. These findings support the view that the inhibition of acetylcholinesterase enzyme is not correlated with cognitive deficits observed in acute and subacute malathion-treated rats.

  20. Occupational Radiation Exposure at Commercial Nuclear Power Reactors and Other Facilities 2010, Prepared for the Nuclear Regulatory Commission, Office of Nuclear Regulatory Research, May 2012

    SciTech Connect

    D. E. Lewis D. A. Hagemeyer Y. U. McCormick

    2012-07-07

    This report summarizes the occupational exposure data that are maintained in the U.S. Nuclear Regulatory Commission’s (NRC) Radiation Exposure Information and Reporting System (REIRS). The bulk of the information contained in the report was compiled from the 2010 annual reports submitted by five of the seven categories of NRC licensees subject to the reporting requirements of 10 CFR 20.2206. Because there are no geologic repositories for high-level waste currently licensed and no NRC-licensed low-level waste disposal facilities currently in operation, only five categories will be considered in this report. The annual reports submitted by these licensees consist of radiation exposure records for each monitored individual. These records are analyzed for trends and presented in this report in terms of collective dose and the distribution of dose among the monitored individuals. Annual reports for 2010 were received from a total of 190 NRC licensees. The summation of reports submitted by the 190 licensees indicated that 192,424 individuals were monitored, 81,961 of whom received a measurable dose. When adjusted for transient workers who worked at more than one licensee during the year, there were actually 142,471 monitored individuals and 62,782 who received a measurable dose. The collective dose incurred by these individuals was 10,617 person-rem, which represents a 12% decrease from the 2009 value. This decrease was primarily due to the decrease in collective dose at commercial nuclear power reactors, as well as a decrease in the collective dose for most of the other categories of NRC licensees. The number of individuals receiving a measurable dose also decreased, resulting in an average measurable dose of 0.13 rem for 2010. The average measurable dose is defined as the total effective dose equivalent (TEDE) divided by the number of individuals receiving a measurable dose. In calendar year 2010, the average annual collective dose per reactor for light water reactor

  1. Acute exposure to wood smoke from incomplete combustion--indications of cytotoxicity.

    PubMed

    Muala, Ala; Rankin, Gregory; Sehlstedt, Maria; Unosson, Jon; Bosson, Jenny A; Behndig, Annelie; Pourazar, Jamshid; Nyström, Robin; Pettersson, Esbjörn; Bergvall, Christoffer; Westerholm, Roger; Jalava, Pasi I; Happo, Mikko S; Uski, Oskari; Hirvonen, Maija-Riitta; Kelly, Frank J; Mudway, Ian S; Blomberg, Anders; Boman, Christoffer; Sandström, Thomas

    2015-10-29

    Smoke from combustion of biomass fuels is a major risk factor for respiratory disease, but the underlying mechanisms are poorly understood. The aim of this study was to determine whether exposure to wood smoke from incomplete combustion would elicit airway inflammation in humans. Fourteen healthy subjects underwent controlled exposures on two separate occasions to filtered air and wood smoke from incomplete combustion with PM1 concentration at 314 μg/m(3) for 3 h in a chamber. Bronchoscopy with bronchial wash (BW), bronchoalveolar lavage (BAL) and endobronchial mucosal biopsies was performed after 24 h. Differential cell counts and soluble components were analyzed, with biopsies stained for inflammatory markers using immunohistochemistry. In parallel experiments, the toxicity of the particulate matter (PM) generated during the chamber exposures was investigated in vitro using the RAW264.7 macrophage cell line. Significant reductions in macrophage, neutrophil and lymphocyte numbers were observed in BW (p < 0.01, <0.05, <0.05, respectively) following the wood smoke exposure, with a reduction in lymphocytes numbers in BAL fluid (<0.01. This unexpected cellular response was accompanied by decreased levels of sICAM-1, MPO and MMP-9 (p < 0.05, <0.05 and <0.01). In contrast, significant increases in submucosal and epithelial CD3+ cells, epithelial CD8+ cells and submucosal mast cells (p < 0.01, <0.05, <0.05 and <0.05, respectively), were observed after wood smoke exposure. The in vitro data demonstrated that wood smoke particles generated under these incomplete combustion conditions induced cell death and DNA damage, with only minor inflammatory responses. Short-term exposure to sooty PAH rich wood smoke did not induce an acute neutrophilic inflammation, a classic hallmark of air pollution exposure in humans. While minor proinflammatory lymphocytic and mast cells effects were observed in the bronchial biopsies, significant reductions in BW and BAL cells and

  2. Repeated exposure to modern volatile anaesthetics may cause chronic hepatitis as well as acute liver injury

    PubMed Central

    Nicoll, Amanda; Moore, David; Njoku, Dolores; Hockey, Brad

    2012-01-01

    Volatile anaesthetic agents are known to cause acute hepatitis and fulminant hepatic failure in susceptible individuals. Four patients were identified with prolonged liver injury due to volatile anaesthetic-induced hepatitis. Three had liver biopsy confirmation and all gave blood for specific diagnostic tests (TFA and CYP 2E1 IgG4 antibodies). The Roussel Uclaf Causality Assessment Method (RUCAM) drug causality scale was used to determine the likelihood of volatile anaesthetics causing the chronic liver injury. We describe four cases of volatile anaesthetic hepatitis in which three evolved into chronic hepatitis. The fourth followed a more typical pattern of acute hepatitis; however, resolution took a few months. These cases all occurred with modern volatile anaesthetics, predominantly sevoflurane, and all cases were proven with specific antibody tests, liver histology and a drug causality scale. This is the first report of chronic liver injury due to volatile anaesthetic exposure. PMID:23131606

  3. Repeated exposure to modern volatile anaesthetics may cause chronic hepatitis as well as acute liver injury.

    PubMed

    Nicoll, Amanda; Moore, David; Njoku, Dolores; Hockey, Brad

    2012-11-06

    Volatile anaesthetic agents are known to cause acute hepatitis and fulminant hepatic failure in susceptible individuals. Four patients were identified with prolonged liver injury due to volatile anaesthetic-induced hepatitis. Three had liver biopsy confirmation and all gave blood for specific diagnostic tests (TFA and CYP 2E1 IgG4 antibodies). The Roussel Uclaf Causality Assessment Method (RUCAM) drug causality scale was used to determine the likelihood of volatile anaesthetics causing the chronic liver injury. We describe four cases of volatile anaesthetic hepatitis in which three evolved into chronic hepatitis. The fourth followed a more typical pattern of acute hepatitis; however, resolution took a few months. These cases all occurred with modern volatile anaesthetics, predominantly sevoflurane, and all cases were proven with specific antibody tests, liver histology and a drug causality scale. This is the first report of chronic liver injury due to volatile anaesthetic exposure.

  4. Measuring the Effect of Environmental Tobacco Smoke on Lung Function: Results From a Small Observational Investigation of Acute Exposure.

    PubMed

    McCormick-Ricket, Iben; Canterberry, Melanie; Ghaffar, Atif; Parada, Nereida A; Carton, Thomas W

    2016-10-01

    Exposure to environmental tobacco smoke (ETS) in smoky venues puts patrons and employees at risk for immediate respiratory symptoms. Although much literature focuses on outcomes associated with chronic ETS exposure, the current study assesses changes in lung function after acute exposure. Ninety-six nonsmoking, healthy adults were exposed to ETS at a bar. Lung function [eg, forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1)] was assessed at baseline, immediately after 3 hours of ETS exposure, and 2 hours after exiting the bar. PM2.5 recordings were also measured. Repeated-measures analysis of variance found significant decreases in FEV1, FVC and FEF25-75%, and peak expiratory flow after ETS exposure compared with baseline that remained significantly decreased after a 2-hour recovery period. Acute exposure to ETS in a natural environment significantly attenuates lung function. A subgroup experienced heightened reductions in lung function.

  5. Modeling Acute Health Effects of Astronauts from Exposure to Large Solar Particle Events

    NASA Technical Reports Server (NTRS)

    Hu, Shaowen; Kim, Myung-Hee Y.; Cucinotta, Francis A.

    2011-01-01

    In space exploration outside the Earth s geomagnetic field, radiation exposure from solar particle events (SPE) presents a health concern for astronauts, that could impair their performance and result in possible failure of the mission. Acute risks are of special concern during extra-vehicular activities because of the rapid onset of SPE. However, most SPEs will not lead to acute risks but can lead to mission disruption if accurate projection methods are not available. Acute Radiation Sickness (ARS) is a group of clinical syndromes developing acutely (within several seconds to 3 days) after high dose whole-body or significant partial-body ionizing radiation exposures. The manifestation of these syndromes reflects the disturbance of physiological processes of various cellular groups damaged by radiation. Hematopoietic cells, skin, epithelium, intestine, and vascular endothelium are among the most sensitive tissues of human body to ionizing radiation. Most ARS symptoms are directly related to these tissues and other systems (nervous, endocrine, and cardiovascular, etc.) with coupled regulations. Here we report the progress in bio-mathematical models to describe the dose and time-dependent early human responses to ionizing radiation. The responses include lymphocyte depression, granulocyte modulation, fatigue and weakness syndrome, and upper gastrointestinal distress. The modest dose and dose-rates of SPEs are predicted to lead to large sparing of ARS, however detailed experimental data on a range of proton dose-rates for organ doses from 0.5 to 2 Gy is needed to validate the models. We also report on the ARRBOD code that integrates the BRYNTRN and SUMDOSE codes, which are used to estimate the SPE organ doses for astronauts under various space travel scenarios, with our models of ARS. The more recent effort is to provide easy web access to space radiation risk assessment using the ARRBOD code.

  6. Acute paraquat exposure impairs colonic motility by selectively attenuating nitrergic signalling in the mouse.

    PubMed

    Diss, Lucy; Dyball, Sarah; Ghela, Tina; Golding, Jonathan; Morris, Rachel; Robinson, Stephen; Tucker, Rosemary; Walter, Talia; Young, Paul; Allen, Marcus; Fidalgo, Sara; Gard, Paul; Mabley, Jon; Patel, Bhavik; Chatterjee, Prabal; Yeoman, Mark

    2016-02-01

    Paraquat, a common herbicide, is responsible for large numbers of deaths worldwide through both deliberate and accidental ingestion. Previous studies have eluded that the bioavailability of paraquat increases substantially with increasing dose and that these changes may in part be due to the effects that these high concentrations have on the gastrointestinal tract (GI tract). To date, the actions of acute, high concentrations (20mM for 60 min) of paraquat on the GI tract, particularly the colon which is a major site of paraquat absorption, are unknown. This study examined the effects of acute paraquat administration on colonic motility in the C57BL/6 mouse. Acute paraquat exposure decreased colonic motility and the amplitude of colonic migrating motor complexes (CMMCs), which are major motor patterns involved in faecal pellet propulsion. In isolated segments of distal colon, paraquat increased resting tension and markedly attenuated electrical field stimulation-evoked relaxations. Pharmacological dissection of paraquat's mechanism of action on both the CMMCs and field stimulated tissue using the nitric oxide synthase inhibitor NG-nitro-L-arginine and direct measurement of NO release from the myenteric plexus, demonstrated that paraquat selectively attenuates nitrergic signalling pathways. These changes did not appear to be due to alterations in colonic oxidative stress, inflammation or complex 1 activity, but were most likely caused by paraquat's ability to act as a redox couple. In summary, these data demonstrate that acute paraquat exposure attenuates colonic transit. These changes may facilitate the absorption of paraquat into the circulation and so facilitate its toxicity.

  7. Acute accidental exposure to chlorine gas: clinical presentation, pulmonary functions and outcomes.

    PubMed

    Mohan, Alladi; Kumar, S Naveen; Rao, M H; Bollineni, S; Manohar, I Chiranjeevi

    2010-01-01

    To study the clinical presentation, pulmonary functions and outcomes in subjects who were accidentally exposed to chlorine gas. Prospective observational study of 64 patients who sustained acute accidental exposure to chlorine gas during a leak in the chlorination system of the public bathing pool of a temple. The major presenting symptoms and signs included acute dyspnoea (100%), chest discomfort (100%), cough (97%), eye irritation (88%), giddiness (72%), vomiting (46%), and heaviness in the head (44%); tachycardia (100%), tachypnoea (96%) and polyphonic wheezing (28%). All patients were managed in the emergency room with humidified oxygen inhalation and beta-2 agonist nebulisation and 52 were discharged within six hours. Twelve patients were severely affected and required hospitalisation; three of them were admitted into the intensive care unit. Three patients developed pulmonary oedema six to eight hours following admission. Pulmonary function testing (n = 12) at presentation revealed obstructive defect in eight and mixed obstructive-cum-restrictive defect in four patients. The mean duration of hospital stay was 5.1 +/- 2.1 days. None of the patients died. Reactive airway dysfunction syndrome (RADS) was observed in three of the 12 hospitalised patients, who complained of manifested persistent cough that lasted for three months period following discharge. Serial pulmonary functions recovered to normal range by the end of the six months in all patients and remained so at one-year follow-up. Acute exposure to chlorine gas is an uncommon, but important public health hazard and can cause RADS, acute lung injury and pulmonary function abnormalities, which are reversible on prompt and appropriate management.

  8. Electrophysiologic and behavioral effects of perinatal and acute exposure of rats to lead and polychlorinated biphenyls.

    PubMed Central

    Carpenter, David O; Hussain, Rifat J; Berger, David F; Lombardo, John P; Park, Hye-Youn

    2002-01-01

    Lead and polychlorinated biphenyls (PCBs) both cause a reduction of intelligence quotient and behavioral abnormalities in exposed children that have features in common with attention deficit hyperactivity disorder. We have used rats as a model to study the effects of both perinatal and acute exposure to lead or PCBs in an effort to compare and understand the mechanisms of these nervous system decrements. Long-term potentiation (LTP) is an electrophysiologic measurement that correlates well with cognitive ability. We have determined the effects of chronic perinatal exposure to lead or PCB 153 as well as acute application of these substances to isolated brain slices, with recordings in two areas of the hippocampus, CA1 and CA3. Both substances, whether chronically or acutely applied, significantly reduced LTP in CA1 in animals at age 30 and 60 days. In CA3, they reduced LTP in 30-day animals but potentiated it in 60-day animals. Although neither lead nor PCB 153 alters baseline synaptic transmission at low stimulus strengths, at higher levels they induce changes in the same direction as those of LTP. These results show surprisingly similar actions of these quite different chemicals, and the similarity of effects on chronic and acute application indicates that effects are both pharmacologic and developmental. Behavioral studies of rats exposed to PCBs from contaminated fish show hyperactivity, impulsiveness, and increased frustration relative to unexposed controls. These results demonstrate that lead and PCBs have similar effects on synaptic plasticity and behavior and suggest that the compounds may act through a common mechanism. PMID:12060832

  9. [Development of a job exposure matrix for the epidemiological follow-up of workers in the French nuclear industry].

    PubMed

    Guseva Canu, I; Molina, G; Goldberg, M; Collomb, P; David, J-C; Perez, P; Paquet, F; Tirmarche, M

    2008-02-01

    A pilot study was carried out in the AREVA NC Pierrelatte nuclear facility in order to investigate a possible carcinogenic effect of internal radiation exposure among nuclear workers in France. The objective of this study was to develop a method for retrospective reconstruction of the occupational exposure to internal radiation from uranium and associated chemical exposures. A plant- and period-specific job exposure matrix (JEM) was designed. Job groups and exposure agents groups including uranium compounds and other chemical agents known as being carcinogenic, mutagenic or toxic were defined by an expert committee. Exposure was evaluated by active and retired workers included in the evaluator committee. A quantitative assignment of quantity and frequency of handling (both coded from 0 to 3) was performed for each agent groups using a method derived from the Delphi technique. In all, 23 experts and 353 evaluators participated to the JEM elaboration. A final JEM involved 232 "job-periods" presenting throughout the plant period 1960-2006 and 22 exposure agents groups in use at the plant. Six of them involved uranium compounds classified by their blood-transferability and toxicity characteristics. A first validation of the JEM by experts in radiological protection and industrial hygiene showed an acceptable internal consistency. In the context of missing past exposure measurement data, the plant- and period-specific job exposure matrices may be considered as a valid alternative for exposure estimation. This method may be applied to other nuclear plants and offers allowance to investigate a possible carcinogenic effect of internal radiation exposure among nuclear workers.

  10. Nuclear emulsion measurements of the astronauts' radiation exposure on the Apollo-Soyuz mission

    NASA Technical Reports Server (NTRS)

    Schaefer, H. J.; Sullivan, J. J.

    1976-01-01

    On the Apollo-Soyuz mission each astronaut carried one passive dosimeter containing nuclear photographic emulsions, plastic foils, TLD chips, and neutron-activation foils for recording radiation exposure. This report is limited to the presentation of data retrieved from nuclear emulsions. Protons, most of them trapped particles encountered in numerous passes through the South Atlantic Anomaly, contributed by far the largest share to the mission dose. Their linear energy transfer (LET) spectrum was established from track and grain counts in a G.5 emulsion which is used for medium and high energies, and from ender counts in a K.2 emulsion which is used for low energies. The total mission fluence of protons was found to be equivalent to a unidirectional beam of 448,500 square centimeters. The broad spectrum was broken down into small LET intervals, which allowed for the computation of absorbed doses and dose equivalents. The totals are 51 millirad and 74 millirem. Counts of disintegration stars in K.2 emulsion are incomplete at present. While a total of 467 stars were identified, counting their prong numbers is still in progress. It was concluded that the Apollo-Soyuz astronauts' radiation exposure as such did not contain anything out of the ordinary that would seem to require special attention.

  11. Induction of micronuclei and nuclear lesions in Channa punctatus following exposure to carbosulfan, glyphosate and atrazine.

    PubMed

    Nwani, Christopher Didigwu; Nagpure, Naresh Sahebrao; Kumar, Ravindra; Kushwaha, Basdeo; Kumar, Pavan; Lakra, Wazir Singh

    2014-10-01

    The genotoxic effects of commonly used agricultural pesticides viz., carbosulfan, glyphosate, and atrazine, were evaluated in Channa punctatus (Pisces, Perciformes) using micronucleus (MN) test and induction of nuclear lesions (NL). The 96 h LC50 value were estimated by probit analysis as 0.27, 32.0 and 42.0 mg L(-1), respectively, for carbosulfan, glyphosate, and atrazine using semi-static bioassays. Based on these values, three sublethal test concentrations of carbosulfan (0.07, 0.13, 0.20 mg L(-1)), glyphosate (8.1, 16.3, 24.4 mg L(-1)) and atrazine (10.6, 21.2, 31.8 mg L(-1)) corresponding to ¼, ½ and ¾ of the LC50 of the pesticides respectively, were selected for exposure for 96 h. Peripheral blood samplings were taken at intervals of 24 h for assessment of MN and NL frequencies. Considerably higher genotoxic damage was induced by carbosulfan as compared to glyphosate and atrazine. There were significant effects (p < 0.01) of concentrations in all the treated groups. The induction of MN and NL was highest at 96 h pesticide exposure at all test concentrations. The nuclear abnormalities recorded in this study, such as blebbed-, lobed-, notched- and bi-nuclei, other than micronuclei, are indicators of genotoxic damage.

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

    DTIC Science & Technology

    2017-03-01

    this project is to test the efficacy and safety of prolonged repetitive exposure to acute intermittent hypoxia (rAIH; 10 episodes per day , 3 to 4... days per week, 3 to 6 months) in a rodent model of chronic, incomplete cervical spinal injury (C2 spinal hemisection in rats; C2HS). In this...respiratory function versus daily AIH for 7 days (as published previously). We predict that functional benefits of rAIH for 3 to 6 months will persist after

  13. Radiation exposure in the acute and short-term management of urolithiasis at 2 academic centers.

    PubMed

    Ferrandino, Michael N; Bagrodia, Aditya; Pierre, Sean A; Scales, Charles D; Rampersaud, Edward; Pearle, Margaret S; Preminger, Glenn M

    2009-02-01

    Diagnostic imaging has a central role in the evaluation and management of urolithiasis. A variety of modalities are available, each with benefits and limitations. Without careful consideration of imaging modalities in quantity and type patients may receive excessive doses of radiation during initial diagnostic and followup evaluations. Therefore, we determined the effective radiation dose associated with an acute stone episode and short-term followup. A multicenter retrospective study of all patients who presented with an acute stone episode was performed. The analysis included all imaging studies related to stone disease performed within 1 year of the acute event. Using accepted effective radiation dose standards for each of these examinations, the total radiation dose administered was calculated and compared by patient characteristics including stone location, stone number and intervention strategy. The primary outcome assessed was a total radiation dose greater than 50 mSv, the recommended yearly dose limit for occupational exposure by the International Commission on Radiological Protection. We identified 108 patients who presented to our respective institutions with a primary acute stone episode between 2000 and 2006. The mean age in our cohort was 48.6 years and 50% of the patients were men. Patients underwent an average of 4 radiographic examinations during the 1-year period. Studies performed included a mean of 1.2 plain abdominal films of the kidneys, ureters and bladder (range 0 to 7), 1.7 abdominopelvic computerized tomograms (range 0 to 6) and 1 excretory urogram (range 0 to 3) during the first year of followup. The median total effective radiation dose per patient was 29.7 mSv (IQR 24.2, 45.1). There were 22 (20%) patients who received greater than 50 mSv. Analysis of stone location, number of stones, stone composition, patient age, sex and surgical intervention indicated no statistically significant difference in the probability of receiving a total

  14. Acute effect of exposure of mollusk single neuron to 900-MHz mobile phone radiation.

    PubMed

    Partsvania, B; Sulaberidze, T; Shoshiashvili, L; Modebadze, Z

    2011-09-01

    The goal of the present work was to explore the influence of commercially available cell phone irradiation on the single neuron excitability and memory processes. A Transverse Electromagnetic Cell (TEM Cell) was used to expose single neurons of mollusk to the electromagnetic field. Finite-Difference Time-Domain (FDTD) method was used for modeling the TEM Cell and the electromagnetic field interactions with living nerve ganglion and neurons. Neuron electrophysiology was investigated using standard microelectrode technique. The specific absorption rate (SAR) deposited into the single neuron was calculated to be 0.63 W/kg with a temperature increment of 0.1°C. After acute exposure, average firing threshold of the action potentials was not changed. However, the average latent period was significantly decreased. This indicates that together with latent period the threshold and the time of habituation might be altered during exposure. However, these alterations are transient and only latent period remains on the changed level.

  15. Acute ethanol exposure affects spermatogonial stem cell homeostasis in pre-pubertal mice.

    PubMed

    Caires, Kyle C; Shima, Christina M; de Avila, Jeanene; McLean, Derek J

    2012-01-01

    Ethanol is a known modulator of neural stem cell development, but the consequences of ethanol toxicity on the cell fate decisions of spermatogonial stem cells (SSCs) is poorly understood. Using an in vivo treatment and stem cell transplantation approach, we investigated the effects of acute ethanol exposure on formation of the growing adult SSC population in neonatal and pre-pubertal mice. Treatment with a single dose of ethanol disrupted SSC homeostasis in vivo evidenced by a significant reduction (7-fold) of stem cell colonization efficiency in the testes of recipient mice following transplantation. Ethanol treatment also increased the rate of apoptosis in adult differentiating germ cells in situ. Gene expression analysis indicates that ethanol exposure has transient and long-term effects on the expression of GDNF and VEGF family molecules and supports the hypothesis that the niche microenvironment for SSCs is sensitive to ethanol toxicity during pre-pubertaland adult life.

  16. Acute vertigo in an anesthesia provider during exposure to a 3T MRI scanner.

    PubMed

    Gorlin, Andrew; Hoxworth, Joseph M; Pavlicek, William; Thunberg, Christopher A; Seamans, David

    2015-01-01

    Vertigo induced by exposure to the magnetic field of a magnetic resonance imaging (MRI) scanner is a well-known phenomenon within the radiology community but is not widely appreciated by other clinical specialists. Here, we describe a case of an anesthetist experiencing acute vertigo while providing sedation to a patient undergoing a 3 Tesla MRI scan. After discussing previous reports, and the evidence surrounding MRI-induced vertigo, we review potential etiologies that include the effects of both static and time-varying magnetic fields on the vestibular apparatus. We conclude our review by discussing the occupational standards that exist for MRI exposure and methods to minimize the risks of MRI-induced vertigo for clinicians working in the MRI environment.

  17. Caudate neuronal recording in freely behaving animals following acute and chronic dose response methylphenidate exposure.

    PubMed

    Claussen, Catherine M; Dafny, Nachum

    2015-09-01

    The misuse and abuse of the psychostimulant, methylphenidate (MPD) the drug of choice in the treatment of attention deficit hyperactivity disorder (ADHD) has seen a sharp uprising in recent years among both youth and adults for its cognitive enhancing effects and for recreational purposes. This uprise in illicit use has lead to many questions concerning the long-term consequences of MPD exposure. The objective of this study was to record animal behavior concomitantly with the caudate nucleus (CN) neuronal activity following acute and repetitive (chronic) dose response exposure to methylphenidate (MPD). A saline control and three MPD dose (0.6, 2.5, and 10.0mg/kg) groups were used. Behaviorally, the same MPD dose in some animals following chronic MPD exposure elicited behavioral sensitization and other animals elicited behavioral tolerance. Based on this finding, the CN neuronal population recorded from animals expressing behavioral sensitization was also evaluated separately from CN neurons recorded from animals expressing behavioral tolerance to chronic MPD exposure, respectively. Significant differences in CN neuronal population responses between the behaviorally sensitized and the behaviorally tolerant animals were observed for the 2.5 and 10.0mg/kg MPD exposed groups. For 2.5mg/kg MPD, behaviorally sensitized animals responded by decreasing their firing rates while behaviorally tolerant animals showed mainly an increase in their firing rates. The CN neuronal responses recorded from the behaviorally sensitized animals following 10.0mg/kg MPD responded by increasing their firing rates whereas the CN neuronal recordings from the behaviorally tolerant animals showed that approximately half decreased their firing rates in response to 10.0mg/kg MPD exposure. The comparison of percentage change in neuronal firing rates showed that the behaviorally tolerant animals trended to exhibit increases in their neuronal firing rates at ED1 following initial MPD exposure and

  18. Caudate neuronal recording in freely behaving animals following acute and chronic dose response methylphenidate exposure

    PubMed Central

    Claussen, Catherine M; Dafny, Nachum

    2016-01-01

    The misuse and abuse of the psychostimulant, methylphenidate (MPD) the drug of choice in the treatment of attention deficit hyperactivity disorder (ADHD) has seen a sharp uprising in recent years among both youth and adults for its cognitive enhancing effects and for recreational purposes. This uprise in illicit use has lead to many questions concerning the long term consequences of MPD exposure. The objective of this study was to record animal behavior concomitantly with the caudate nucleus (CN) neuronal activity following acute and repetitive (chronic) dose response exposure to methylphenidate (MPD). A saline control and three MPD dose (0.6, 2.5, and 10.0 mg/kg) groups were used. Behaviorally, the same MPD dose in some animals following chronic MPD exposure elicited behavioral sensitization and other animals elicited behavioral tolerance. Based on this finding, the CN neuronal population recorded from animals expressing behavioral sensitization were also evaluated separately from CN neurons recorded from animals expressing behavioral tolerance to chronic MPD exposure, respectively. Significant differences in CN neuronal population responses between the behaviorally sensitized and the behaviorally tolerant animals was observed for the 2.5 and 10.0 mg/kg MPD exposed groups. For 2.5 mg/kg MPD, behaviorally sensitized animals responded by decreasing their firing rates while behaviorally tolerant animals showed mainly an increase in their firing rates. The CN neuronal responses recorded from the behaviorally sensitized animals following 10.0 mg/kg MPD responded by increasing their firing rates whereas the CN neuronal recordings from the behaviorally tolerant animals showed that approximately half decreased their firing rates in response to 10.0 mg/kg MPD exposure. The comparison of percentage change in neuronal firing rates showed that the behaviorally tolerant animals trended to exhibit increases in their neuronal firing rates at ED1 following initial MPD exposure

  19. Effects of acute ozone exposure on the electrophysiological properties of guinea pig trachea

    SciTech Connect

    Croxton, T.L.; Takahashi, Masahiko; Kokia, Ira

    1994-12-31

    Acute ozone (O{sub 3}) exposures produce an increase in the apparent permeability of the tracheal epithelium, but the mechanism of this response is poorly understood. Comparison of previous studies suggests that qualitative differences may exist between measurements made in vivo or in vitro. To test this possibility we used both in vitro and in vivo electrophysiological techniques to investigate the effects of O{sub 3} exposure on guinea pig tracheal epithelium. Male Hartley guinea pigs were exposed to either 1 or 2 ppm O{sub 3} or to filtered air for 3 h and were studied 0, 6, or 24 h after exposure. Air-exposed animals had in vitro mean tracheal potential (V{sub T}) -32.0 {+-} 1.5 mV, conductance (G{sub T}{sup L}) 2.18 {+-} 0.22 mS/cm, short-circuit current (I{sub SC}{sup L}) 62.6 {+-} 3.7 {mu}A/cm, and diameter (D) 2.44 {+-} 0.10 mm. In vitro properties after 1 ppm O{sub 3} exposure did not differ at any time point from control. Two parts per million O{sub 3} increased I{sub SC}{sup L}, but only at 6 h postexposure. The effect of O{sub 3} on I{sub SC}{sup L} was abolished by amiloride. There were no significant changes in V{sub T}, G{sub T}{sup L}, or D. In vivo tracheal potential under pentobarbital anesthesia was -19.7 {+-} 1.7 mV. At 6 h postexposure to 2 ppm O{sub 3}, but not at 0 or 24 h, in vivo V{sub I} was increased. Thus, acute exposure of guinea pigs to a high concentration of O{sub 3} caused a delayed increase in Na{sup +} absorption by the trachea with no change in conductance. This indicates that paracellular permeability of guinea pig tracheal epithelium was not substantially increased by acute O{sub 3} and suggests that enhanced macromolecular uptake in this species probably occurs transcellularly. 24 refs., 1 fig., 2 tabs.

  20. Acute exposure of Drosophila melanogaster to paraquat causes oxidative stress and mitochondrial dysfunction.

    PubMed

    Hosamani, Ravikumar

    2013-05-01

    Paraquat (PQ; 1, 1'-dimethyl-4-4'-bipyridinium), an herbicide and model neurotoxicant, is identified to be one of the prime risk factors in Parkinson's disease (PD). In the Drosophila system, PQ is commonly used to measure acquired resistance against oxidative stress (PQ resistance test). Despite this, under acute PQ exposure, data on the oxidative stress response and associated impact on mitochondria among flies is limited. Accordingly, in this study, we measured markers of oxidative stress and mitochondrial dysfunctions among adult male flies (8-10 days old) exposed to varying concentrations of PQ (10, 20, and 40 mM in 5% sucrose solution) employing a conventional filter disc method for 24 h. PQ exposure resulted in significant elevation in the levels of oxidative stress biomarkers (malondialdehyde: 43% increase: hydroperoxide: 32-39% increase), with concomitant enhancement in reduced glutathione and total thiol levels in cytosol. Higher activity of antioxidant enzymes were also evident along with increased free iron levels. Furthermore, PQ exposure caused a concentration-dependent increase in mitochondrial superoxide generation and activity of manganese-superoxide dismutase (Mn-SOD). The activity levels of complex I-III, complex II-III, and Mg+2 adinosine triphosphatase (ATPase) were also decreased significantly. A robust diminution in the activity of succinate dehydrogenase and moderate decline in the citrate synthase activity suggested a specific effect on citric acid cycle enzymes. Collectively, these data suggest that acute PQ exposure causes significant oxidative stress and mitochondrial dysfunction among flies in vivo. It is suggested that in various experimental settings, while conducting the "PQ resistance stress test" incorporation of selected biochemical end points is likely to enhance the quality of the data.

  1. Acute Inhalation Exposure to Vaporized Methamphetamine Causes Lung Injury in Mice

    PubMed Central

    Wells, Sandra M.; Buford, Mary C.; Braseth, Sarah N.; Hutchison, James D.; Holian, Andrij

    2009-01-01

    Methamphetamine (MA) is currently the most widespread illegally used stimulant in the United States. Use of MA by smoking is the fastest growing mode of administration, which increases concerns about potential pulmonary and other medical complications. A murine exposure system was developed to study the pulmonary affects of inhaled MA. Mice were exposed to 25–100 mg vaporized MA and assessments were made 3 h following initiation of exposure to model acute lung injury. Inhalation of MA vapor resulted in dose-dependent increases in MA plasma levels that were in the range of those experienced by MA users. At the highest MA dose, histological changes were observed in the lung and small but significant increases in lung wet weight to body weight ratios (5.656 ± 0.176 mg/g for the controls vs. 6.706± 0.135 mg/g for the 100 mg MA-exposed mice) were found. In addition, there was 53% increase in total protein in bronchoalveolar lavage (BAL) fluid, greater than 20% increase in albumin levels in the BAL fluid, greater than 2.5-fold increase in lactate dehydrogenase levels in the BAL fluid, and reduced total BAL cell numbers (approximately 77% of controls). Levels of the early response cytokines tumor necrosis factor (TNF)-α and interleukin (IL)-6 were dose-dependently increased in BAL fluid of MA-exposed mice. Exposure to 100 mg MA significantly increased free radical generation in the BAL cells to 107–146% of controls and to approximately 135% of the controls in lung tissue in situ. Together, these data show that acute inhalation exposure to relevant doses of volatilized MA is associated with elevated free radical formation and significant lung injury. PMID:18645723

  2. Agility And Vertical Jump Performances Are Impacted By Acute Cool Exposure.

    PubMed

    Carlson, Lara A; Fowler, Cara; Lawrence, Michael A

    2017-07-08

    Outdoor sports teams may be exposed to acute cold stress during competition, which may affect performance. Limited research has explored the effects of cold exposure on athletic components. The purpose of this study was to examine the effects of an acute whole-body cool exposure on pro-agility, vertical jump, and sprint performances. Eleven lightly clothed (∼0.3 clo) and not cold acclimatized volunteers (10/1 women/men: age 20.5 ± 0.5 y; height 1.65 ± 0.09 m; mass 63.3 ± 8.9 kg; body fat 21.3 ± 7.6%) completed performance tests in both thermoneutral (17.2°C, 36% relative humidity, Biddeford, Maine, USA) and cool (6.1°C, 72% relative humidity, Thorsmörk, Iceland) ambient temperatures. Prior to completing the performance tests, subjects engaged in a 5 min stretching routine and were subsequently exposed to either a thermoneutral or cool ambient environment for 15 min. Performance tests included three trials of maximal vertical jumps, and two trials of both the 36.6 m sprint and pro-agility tests. Mean performance and lactate values were compared via paired t-tests. Pro-agility completion time was significantly (p<0.05) slower in the cool (5.63 ± 0.33 s) than thermoneutral (5.43 ± 0.26 s) environment. Vertical jump was significantly (p<0.05) lower in the cool (0.36 ± 0.07 m) than thermoneutral (0.41 ± 0.10 m) environment. Sprint performance and lactate values were unaffected by the cool exposure. Brief cool exposure appears to influence agility and vertical jump performances. Our results suggest that it would be prudent for athletes and coaches to consider the ambient environment when preparing for competition.

  3. Acute exposure to the penconazole-containing fungicide Topas partially augments antioxidant potential in goldfish tissues.

    PubMed

    Husak, Viktor V; Mosiichuk, Nadia M; Storey, Janet M; Storey, Kenneth B; Lushchak, Volodymyr I

    2017-03-01

    Penconazole is a systemic fungicide commonly used in agriculture as the commercial preparation Topas. Although triazole fungicides are widely found in the aquatic environment, little is known about their acute toxicity on fish. In this study we assessed the effects of short-term exposure to Topas on some parameters of homeostasis of reactive oxygen species (ROS), such as the levels of markers of oxidative stress and parameters of the antioxidant defense system of goldfish (Carassius auratus L.). Gills appeared to be the main target organ of Topas toxicity, showing the greatest number of parameters affected. Gills of Topas-treated fish showed a higher content of low (L-SH) and high (H-SH) molecular mass thiols and higher activities of superoxide dismutase (SOD), catalase, glutathione reductase (GR), glutathione-S-transferase (GST), and glucose-6-phosphate dehydrogenase (G6PDH) as well as reduced carbonyl protein content (CP), as compared with those in the control group. In the liver, goldfish exposure to 15-25mgL(-1) Topas resulted in a higher L-SH and H-SH content, but lower CP levels and activity of GST. In kidney, Topas exposure resulted in higher activities of glutathione peroxidase (GPx) and G6PDH, but lower L-SH content and activity of GST. The results of this study indicate that acute goldfish exposure to the triazole fungicide Topas increased efficiency of the antioxidant system in fish gills, liver, and kidney. This could indicate the development of low intensity oxidative stress which up-regulates defense mechanisms responsible for protection of goldfish against deleterious ROS effects. Copyright © 2016. Published by Elsevier Inc.

  4. Analyses of differentially expressed genes after exposure to acute stress, acute ethanol, or a combination of both in mice.

    PubMed

    Baker, Jessica A; Li, Jingxin; Zhou, Diana; Yang, Ming; Cook, Melloni N; Jones, Byron C; Mulligan, Megan K; Hamre, Kristin M; Lu, Lu

    2017-02-01

    Alcohol abuse is a complex disorder, which is confounded by other factors, including stress. In the present study, we examined gene expression in the hippocampus of BXD recombinant inbred mice after exposure to ethanol (NOE), stress (RSS), and the combination of both (RSE). Mice were given an intraperitoneal (i.p.) injection of 1.8 g/kg ethanol or saline, and subsets of both groups were exposed to acute restraint stress for 15 min or controls. Gene expression in the hippocampus was examined using microarray analysis. Genes that were significantly (p < 0.05, q < 0.1) differentially expressed were further evaluated. Bioinformatic analyses were predominantly performed using tools available at GeneNetwork.org, and included gene ontology, presence of cis-regulation or polymorphisms, phenotype correlations, and principal component analyses. Comparisons of differential gene expression between groups showed little overlap. Gene Ontology demonstrated distinct biological processes in each group with the combined exposure (RSE) being unique from either the ethanol (NOE) or stress (RSS) group, suggesting that the interaction between these variables is mediated through diverse molecular pathways. This supports the hypothesis that exposure to stress alters ethanol-induced gene expression changes and that exposure to alcohol alters stress-induced gene expression changes. Behavior was profiled in all groups following treatment, and many of the differentially expressed genes are correlated with behavioral variation within experimental groups. Interestingly, in each group several genes were correlated with the same phenotype, suggesting that these genes are the potential origins of significant genetic networks. The distinct sets of differentially expressed genes within each group provide the basis for identifying molecular networks that may aid in understanding the complex interactions between stress and ethanol, and potentially provide relevant therapeutic targets. Using Ptp4

  5. GENE EXPRESSION CHANGES IN FEMALE ZEBRAFISH (DANIO RERIO) BRAIN IN RESPONSE TO ACUTE EXPOSURE TO METHYLMERCURY

    PubMed Central

    Richter, Catherine A.; Garcia-Reyero, Natàlia; Martyniuk, Chris; Knoebl, Iris; Pope, Marie; Wright-Osment, Maureen K.; Denslow, Nancy D.; Tillitt, Donald E.

    2010-01-01

    Methylmercury (MeHg) is a potent neurotoxicant and endocrine disruptor that accumulates in aquatic systems. Previous studies have shown suppression of hormone levels in both male and female fish, suggesting effects on gonadotropin regulation in the brain. The gene expression profile in adult female zebrafish whole brain induced by acute (96 hr) MeHg exposure was investigated. Fish were exposed by injection to 0 or 0.5 μg MeHg/g. Gene expression changes in the brain were examined using a 22,000 feature zebrafish microarray. At a significance level of p<0.01, 79 genes were up-regulated and 76 genes were down-regulated in response to MeHg exposure. Individual genes exhibiting altered expression in response to MeHg exposure implicate effects on glutathione metabolism in the mechanism of MeHg neurotoxicity. Gene ontology (GO) terms significantly enriched among altered genes included protein folding, cell redox homeostasis, and steroid biosynthetic process. The most affected biological functions were related to the nervous system development and function, as well as lipid metabolism and molecular transport. These results support the involvement of oxidative stress and effects on protein structure in the mechanism of action of MeHg in the female brain. Future studies will compare the gene expression profile induced in response to MeHg with that induced by other toxicants and investigate responsive genes as potential biomarkers of MeHg exposure. PMID:21082716

  6. Acute bronchiolar injury following nitrogen dioxide exposure: a freeze fracture study

    SciTech Connect

    Case, B.W.; Gordon, R.E.; Kleinerman, J.

    1982-12-01

    Three groups of Syrian golden hamsters were exposed to NO/sub 2/ for 6, 24, or 48 hr to determine acute effects on intercellular junctional morphology in distal airways and alveolar epithelium. A fourth group, exposed for 48 hr, was allowed to recover for 2 days prior to sacrifice. Light and transmission electron microscopy of bronchiolar epithelium show ciliary loss and surface membrane damage, loss of ciliated cells, and epithelial flattening at 24 and 48 hr. Moderate to marked epithelial hyperplasia and nonciliated cell hypertrophy are noted after 48 hr. Some restoration of normal histoarchitecture is noted in bronchioles of animals allowed a 48-hr recovery period. Freeze fracture platinum-carbon replicas of bronchiolar epithelium show the gradual evolution of a severe disruption of tight junctional networks after 6, 24, and 48 hr of exposure. Following 2 days of ''recovery,'' bronchiolar tight junctions from animals exposed for 48 hr remain fragmented. The wide distribution of the junctionl material present suggests a regenerative process. Freeze fracture replicas of bronchial epithelium show similar fragmentation of tight junctions following 6-hr exposures. After longer intervals, however, there is a return to more normal appearances. Duration of NO/sub 2/ exposure has no systematic effect on the integrity of tight junctions in alveolar epithelium. The findings suggest that disruption of tight junctions may be an important specific determinant of increased bronchiolar epithelial permeability following brief exposures to nitrogen dioxide.

  7. Gene expression changes in female zebrafish (Danio rerio) brain in response to acute exposure to methylmercury

    USGS Publications Warehouse

    Richter, Catherine A.; Garcia-Reyero, Natàlia; Martyniuk, Chris; Knoebl, Iris; Pope, Marie; Wright-Osment, Maureen K.; Denslow, Nancy D.; Tillitt, Donald E.

    2011-01-01

    Methylmercury (MeHg) is a potent neurotoxicant and endocrine disruptor that accumulates in aquatic systems. Previous studies have shown suppression of hormone levels in both male and female fish, suggesting effects on gonadotropin regulation in the brain. The gene expression profile in adult female zebrafish whole brain induced by acute (96 h) MeHg exposure was investigated. Fish were exposed by injection to 0 or 0.5(mu or u)g MeHg/g. Gene expression changes in the brain were examined using a 22,000-feature zebrafish microarray. At a significance level of pexposure. Individual genes exhibiting altered expression in response to MeHg exposure implicate effects on glutathione metabolism in the mechanism of MeHg neurotoxicity. Gene ontology (GO) terms significantly enriched among altered genes included protein folding, cell redox homeostasis, and steroid biosynthetic process. The most affected biological functions were related to nervous system development and function, as well as lipid metabolism and molecular transport. These results support the involvement of oxidative stress and effects on protein structure in the mechanism of action of MeHg in the female brain. Future studies will compare the gene expression profile induced in response to MeHg with that induced by other toxicants and will investigate responsive genes as potential biomarkers of MeHg exposure.

  8. Acute exposure to blue wavelength light during memory consolidation improves verbal memory performance

    PubMed Central

    Smith, Ryan; Dailey, Natalie S.; Bajaj, Sahil; Killgore, William D. S.

    2017-01-01

    Acute exposure to light within the blue wavelengths has been shown to enhance alertness and vigilance, and lead to improved speed on reaction time tasks, possibly due to activation of the noradrenergic system. It remains unclear, however, whether the effects of blue light extend beyond simple alertness processes to also enhance other aspects of cognition, such as memory performance. The aim of this study was to investigate the effects of a thirty minute pulse of blue light versus placebo (amber light) exposure in healthy normally rested individuals in the morning during verbal memory consolidation (i.e., 1.5 hours after memory acquisition) using an abbreviated version of the California Verbal Learning Test (CVLT-II). At delayed recall, individuals who received blue light (n = 12) during the consolidation period showed significantly better long-delay verbal recall than individuals who received amber light exposure (n = 18), while controlling for the effects of general intelligence, depressive symptoms and habitual wake time. These findings extend previous work demonstrating the effect of blue light on brain activation and alertness to further demonstrate its effectiveness at facilitating better memory consolidation and subsequent retention of verbal material. Although preliminary, these findings point to a potential application of blue wavelength light to optimize memory performance in healthy populations. It remains to be determined whether blue light exposure may also enhance performance in clinical populations with memory deficits. PMID:28922397

  9. Severe acute oxidant exposure: morphological damage and aerobic metabolism in the lung

    SciTech Connect

    Montgomery, M.R.; Teuscher, F.; LaSota, I.; Niewoehner, D.E.

    1986-09-01

    Groups of male rats were exposed to acute doses of oxygen, ozone, or paraquat which produced equivalent mortality (25-30%) over a 28 day post-exposure period. Quantitative evaluation of morphological changes indicated the primary response to be edema and inflammation with only slight fibrosis being apparent by the end of the observation period. Aerobic pulmonary metabolism was inhibited in lungs from animals exposed to oxygen and ozone as evidenced by decreased oxygen consumption; however, this was transient and O/sub 2/ consumption returned to normal within 24 hours after removal from the exposure chamber. Conversely, treatment with paraquat caused an immediate, transient stimulation of O/sub 2/ consumption. Glucose metabolism was unaltered by the gas exposures and, as previously reported, was initially stimulated by paraquat treatment. In vitro, only paraquat altered both O/sub 2/ consumption and glucose metabolism when added to lung slice preparations; ozone had no effect. Oxygen did not alter O/sub 2/ consumption but caused a slight biphasic response in glucose metabolism. Aerobic metabolism is relatively unchanged by these doses of oxygen and ozone which result in the death of 25-30% of all treated animals. Even though paraquat produces similar morphologic changes, it may represent a more severe metabolic insult than ''equivalent'' doses of oxygen or ozone. Also, if interstitial pulmonary fibrosis is a desired result of experimental exposure, rats may not be a suitable model for oxidant induced lung injury.

  10. Acute exposure to ethanol on gestational day 15 affects social motivation of female offspring.

    PubMed

    Varlinskaya, Elena I; Mooney, Sandra M

    2014-03-15

    Alterations in social behavior are a hallmark of many neurodevelopmental disorders in humans. In rodents, social behavior is affected by prenatal insults. The outcomes are dependent on the timing of the insult as well as the sex and age of the animal tested. The limbic system is particularly important for social behavior, and a peak of neurogenesis within this system occurs on gestational day (G)15. Neurons appear particularly vulnerable to ethanol insult around the time they become post-mitotic. We tested the hypothesis that acute exposure to ethanol on G15 would result in significant social behavior deficits. Accordingly, Long Evans pregnant females were injected with ethanol (2.9 g/kg) or an equivalent volume of saline on G15. Offspring were assessed in a modified social interaction test on postnatal day (P) 28, P42, or P75, i.e., during early adolescence, late adolescence, or young adulthood. Prenatal ethanol exposure decreased social investigation in P28 females and transformed social preference into social avoidance in 75-day-old females. Contact behavior, play fighting, and locomotor activity differed as a function of age, but were not significantly affected by ethanol exposure. Males demonstrated significantly more contact behavior and play fighting at P42 than at P28 or P70, whereas there were no age-related changes in females. Adult females showed more locomotor activity than adult males. Overall, prenatal ethanol exposure on G15 enhanced social anxiety in females, with these effects seen in adulthood only.

  11. The desmosomal protein desmoglein 1 aids recovery of epidermal differentiation after acute UV light exposure.

    PubMed

    Johnson, Jodi L; Koetsier, Jennifer L; Sirico, Anna; Agidi, Ada T; Antonini, Dario; Missero, Caterina; Green, Kathleen J

    2014-08-01

    Epidermal structure is damaged by exposure to UV light, but the molecular mechanisms governing structural repair are largely unknown. UVB (290-320 nm wavelengths) exposure before induction of differentiation reduced expression of differentiation-associated proteins, including desmoglein 1 (Dsg1), desmocollin 1 (Dsc1), and keratins 1 and 10 (K1/K10), in a dose-dependent manner in normal human epidermal keratinocytes (NHEKs). The UVB-induced reduction in both Dsg1 transcript and protein was associated with reduced binding of the p63 transcription factor to previously unreported enhancer regulatory regions of the Dsg1 gene. As Dsg1 promotes epidermal differentiation in addition to participating in cell-cell adhesion, the role of Dsg1 in aiding differentiation after UVB damage was tested. Compared with controls, depleting Dsg1 via short hairpin RNA resulted in further reduction of Dsc1 and K1/K10 expression in monolayer NHEK cultures and in abnormal epidermal architecture in organotypic skin models recovering from UVB exposure. Ectopic expression of Dsg1 in keratinocyte monolayers rescued the UVB-induced differentiation defect. Treatment of UVB-exposed monolayer or organotypic cultures with trichostatin A, a histone deacetylase inhibitor, partially restored differentiation marker expression, suggesting a potential therapeutic strategy for reversing UV-induced impairment of epidermal differentiation after acute sun exposure.

  12. Seasonal variations in the responses of glycolytic intermediates of human erythrocytes to acute cold exposure

    NASA Astrophysics Data System (ADS)

    Ohno, H.; Yahata, T.; Yamashita, K.; Kuroshima, A.

    1988-03-01

    Seven male students were studied to observe the effects of acute cold exposure (at 10°C for 60 min) on erythrocyte concentrations of glycolytic intermediates in summer and in winter. The subjects shivered slightly but frankly in both experiments. Significant decreases were observed in the concentrations of pyruvate and lactate during body cooling in summer, but not in winter. The lactate concentration remained significantly reduced 15 min after cold exposure. After 60 min of cold exposure in summer, a negative crossover point appeared to exist between phosphoenolpyruvate and pyruvate and erythrocyte pyruvate kinase activity showed a significant decrease. No seasonal difference was observed in the initial control values of the intermediates measured. From these results and the fact that glucose, pyruvate and lactate are evenly distributed between erythrocytes and plasma, it is likely that erythrocytes and skeletal muscles need less fuel substrate, glucose during cold exposure in winter than in summer, suggesting that an increased economy of energy for homeostasis is achieved.

  13. The desmosomal protein Desmoglein 1 aids recovery of epidermal differentiation after acute ultraviolet light exposure

    PubMed Central

    Johnson, Jodi L.; Koetsier, Jennifer L.; Sirico, Anna; Agidi, Ada T.; Antonini, Dario; Missero, Caterina; Green, Kathleen J.

    2014-01-01

    Epidermal structure is damaged by exposure to ultraviolet (UV) light but the molecular mechanisms governing structural repair are largely unknown. UVB (290-320 nm wavelengths) exposure prior to induction of differentiation reduced expression of differentiation-associated proteins, including Desmoglein 1 (Dsg1), Desmocollin 1 (Dsc1) and Keratins 1 and 10 (K1/K10) in a dose-dependent manner in normal human epidermal keratinocytes (NHEKs). The UVB- induced reduction in both Dsg1 transcript and protein was associated with reduced binding of the p63 transcription factor to previously unreported enhancer regulatory regions of the Dsg1 gene. Since Dsg1 promotes epidermal differentiation in addition to participating in cell-cell adhesion, the role of Dsg1 in aiding differentiation after UVB damage was tested. Compared to controls, depleting Dsg1 via shRNA resulted in further reduction of Dsc1 and K1/K10 expression in monolayer NHEK cultures and in abnormal epidermal architecture in organotypic skin models recovering from UVB exposure. Ectopic expression of Dsg1 in keratinocyte monolayers rescued the UVB-induced differentiation defect. Treatment of UVB-exposed monolayer or organotypic cultures with Trichostatin A, a histone deacetylase inhibitor, partially restored differentiation marker expression, suggesting a potential therapeutic strategy for reversing UV-induced impairment of epidermal differentiation after acute sun exposure. PMID:24594668

  14. Acute exposure to blue wavelength light during memory consolidation improves verbal memory performance.

    PubMed

    Alkozei, Anna; Smith, Ryan; Dailey, Natalie S; Bajaj, Sahil; Killgore, William D S

    2017-01-01

    Acute exposure to light within the blue wavelengths has been shown to enhance alertness and vigilance, and lead to improved speed on reaction time tasks, possibly due to activation of the noradrenergic system. It remains unclear, however, whether the effects of blue light extend beyond simple alertness processes to also enhance other aspects of cognition, such as memory performance. The aim of this study was to investigate the effects of a thirty minute pulse of blue light versus placebo (amber light) exposure in healthy normally rested individuals in the morning during verbal memory consolidation (i.e., 1.5 hours after memory acquisition) using an abbreviated version of the California Verbal Learning Test (CVLT-II). At delayed recall, individuals who received blue light (n = 12) during the consolidation period showed significantly better long-delay verbal recall than individuals who received amber light exposure (n = 18), while controlling for the effects of general intelligence, depressive symptoms and habitual wake time. These findings extend previous work demonstrating the effect of blue light on brain activation and alertness to further demonstrate its effectiveness at facilitating better memory consolidation and subsequent retention of verbal material. Although preliminary, these findings point to a potential application of blue wavelength light to optimize memory performance in healthy populations. It remains to be determined whether blue light exposure may also enhance performance in clinical populations with memory deficits.

  15. Exposure to Discrimination and Heart Rate Variability Reactivity to Acute Stress among Women with Diabetes.

    PubMed

    Wagner, Julie; Lampert, Rachel; Tennen, Howard; Feinn, Richard

    2015-08-01

    Exposure to racial discrimination has been linked to physiological reactivity. This study investigated self-reported exposure to racial discrimination and parasympathetic [high-frequency heart rate variability (HF-HRV)] and sympathetic (norepinephrine and cortisol) activity at baseline and then again after acute laboratory stress. Lifetime exposure to racial discrimination was measured with the Schedule of Racist Events scale. Thirty-two women (16 Black and 16 White) with type 2 diabetes performed a public speaking stressor. Beat-to-beat intervals were recorded on electrocardiograph recorders, and HF-HRV was calculated using spectral analysis and natural log transformed. Norepinephrine and cortisol were measured in blood. Higher discrimination predicted lower stressor HF-HRV, even after controlling for baseline HF-HRV. When race, age, A1c and baseline systolic blood pressure were also controlled, racial discrimination remained a significant independent predictor of stressor HF-HRV. There was no association between lifetime discrimination and sympathetic markers. In conclusion, preliminary data suggest that among women with type 2 diabetes mellitus (T2DM), exposure to racial discrimination is adversely associated with parasympathetic, but not sympathetic, reactivity. Copyright © 2013 John Wiley & Sons, Ltd.

  16. The effects of nicotine on the metabolic and hormonal responses during acute cold exposure.

    PubMed

    Cheatham, Christopher C; Caine-Bish, Natalie; Blegen, Mark; Potkanowicz, Edward S; Kamimori, Gary H; Marcinkiewicz, Jennifer L; Otterstetter, Ronald; Kalinski, Michael; Glickman, Ellen L

    2006-01-01

    To examine the effects of nicotine on the metabolic and hormonal responses during acute cold exposure. Participants in this study included 6 men and 5 women between the ages of 19 and 25 years. Each subject performed 2 cold-air trials (CATs) consisting of a 30-minute baseline (BASE) period and a 120-minute exposure to 10 degree C air. One CAT was performed after a nicotine (NIC) dosing using a 21-mg transdermal patch, whereas the other CAT was performed after a placebo (PL) treatment. Blood samples for metabolic and hormonal measurements were obtained at the end of BASE and immediately after the cold exposure. When examining the sexes separately, there was no difference in norepinephrine between PL and NIC (P = .066). There was also no difference in epinephrine between PL and NIC in either sex (P = .634). From BASE to 120 minutes of the CAT, there was a significant decrease in cortisol (P = .036), but this response was similar between the 2 treatments (P = .077). Glucose and glycerol concentrations were not different between the PL and NIC treatments. At BASE, nonesterified fatty acid (NEFA) concentration was lower during PL compared with NIC (P = .021); however, at 120 minutes of the CAT, NEFA was greater during PL compared with NIC (P = .035). During 120 minutes of cold exposure, NIC resulted in alterations in the responses in NEFA, whereas the other blood measurements were not significantly different between the 2 groups.

  17. Long-term exposure to air pollution is associated with survival following acute coronary syndrome.

    PubMed

    Tonne, Cathryn; Wilkinson, Paul

    2013-05-01

    The aim of this study was to determine (i) whether long-term exposure to air pollution was associated with all-cause mortality using the Myocardial Ischaemia National Audit Project (MINAP) data for England and Wales, and (ii) the extent to which exposure to air pollution contributed to socioeconomic inequalities in prognosis. Records of patients admitted to hospital with acute coronary syndrome (ACS) in MINAP collected under the National Institute for Cardiovascular Outcomes Research were linked to modelled annual average air pollution concentrations for 2004-10. Hazard ratios for mortality starting 28 days after admission were estimated using Cox proportional hazards models. Among the 154 204 patients included in the cohort, the average follow-up was 3.7 years and there were 39 863 deaths. Mortality rates were higher for individuals exposed to higher levels of particles with a diameter of ≤2.5 µm (PM2.5; PM, particulate matter): the fully adjusted hazard ratio for a 10 µg/m(3) increase in PM2.5 was 1.20 (95% CI 1.04-1.38). No associations were observed for larger particles or oxides of nitrogen. Air pollution explained socioeconomic inequalities in survival to only a small extent. Mortality from all causes was higher among individuals with greater exposure to PM2.5 in survivors of hospital admission for ACS in England and Wales. Despite higher exposure to PM2.5 among those from more deprived areas, such exposure was a minor contribution to the socioeconomic inequalities in prognosis following ACS. Our findings add to the evidence of mortality associated with long-term exposure to fine particles.

  18. Acute Air Pollution Exposure and Blood Pressure at Delivery Among Women With and Without Hypertension

    PubMed Central

    Männistö, Tuija; Liu, Danping; Leishear, Kira; Sherman, Seth; Laughon, S. Katherine

    2015-01-01

    BACKGROUND Chronic air pollution exposure increases risk for hypertensive disorders of pregnancy, but the effect of acute air pollution exposure on blood pressure during pregnancy is less well known. METHODS We studied 151,276 singleton term deliveries from the Consortium on Safe Labor (2002–2008) with clinical blood pressure measured at admission to labor/delivery and diagnoses of hypertensive disorders collected from electronic medical records and hospital discharge summaries. Air pollution exposures were estimated for the admission hour and the 4 hours preceding admission using a modified version of the Community Multiscale Air Quality models and observed air monitoring data. Blood pressure was categorized as normal; high normal; and mild, moderate, or severe hypertension based on pregnancy cut points. Adjusted ordinal logistic regression estimated the odds of women having a higher admission blood pressure category as a function of air pollutant, hypertensive disorders, and their interaction effect. RESULTS Odds of high blood pressure at admission to labor/delivery were increased in normotensive women after exposure to nitrogen oxides (by 0.2%/5 units), sulfur dioxide (by 0.3%/1 unit), carbon monoxide and several air toxics (by 3%–4%/high exposure). The effects were often similar or stronger among women with gestational hypertension and preeclampsia. Exposure to particulate matter <10 μm increased odds of high blood pressure in women with preeclampsia by 3%/5 units. CONCLUSIONS Air pollution can influence admission blood pressure in term deliveries and may increase likelihood of preeclampsia screening at delivery admission. PMID:24795401

  19. Acute air pollution exposure and blood pressure at delivery among women with and without hypertension.

    PubMed

    Männistö, Tuija; Mendola, Pauline; Liu, Danping; Leishear, Kira; Sherman, Seth; Laughon, S Katherine

    2015-01-01

    Chronic air pollution exposure increases risk for hypertensive disorders of pregnancy, but the effect of acute air pollution exposure on blood pressure during pregnancy is less well known. We studied 151,276 singleton term deliveries from the Consortium on Safe Labor (2002-2008) with clinical blood pressure measured at admission to labor/delivery and diagnoses of hypertensive disorders collected from electronic medical records and hospital discharge summaries. Air pollution exposures were estimated for the admission hour and the 4 hours preceding admission using a modified version of the Community Multiscale Air Quality models and observed air monitoring data. Blood pressure was categorized as normal; high normal; and mild, moderate, or severe hypertension based on pregnancy cut points. Adjusted ordinal logistic regression estimated the odds of women having a higher admission blood pressure category as a function of air pollutant, hypertensive disorders, and their interaction effect. Odds of high blood pressure at admission to labor/delivery were increased in normotensive women after exposure to nitrogen oxides (by 0.2%/5 units), sulfur dioxide (by 0.3%/1 unit), carbon monoxide and several air toxics (by 3%-4%/high exposure). The effects were often similar or stronger among women with gestational hypertension and preeclampsia. Exposure to particulate matter <10 μm increased odds of high blood pressure in women with preeclampsia by 3%/5 units. Air pollution can influence admission blood pressure in term deliveries and may increase likelihood of preeclampsia screening at delivery admission. © Published by Oxford University Press on behalf of American Journal of Hypertension Ltd 2014. This work is written by (a) US Government employees(s) and is in the public domain in the US.

  20. Porcine mononuclear leukocyte nuclear thyroid hormone receptors: Effects of cold exposure on receptor kinetics

    SciTech Connect

    D'Alesandro, M.; Reed, L.; Malik, M.; Quesada, M.; Hesslink, R.; Castro, S.; Homer, L.; Young, B. Univ. of Alberta, Edmonton )

    1991-03-11

    Changes in kinetic characteristics of the triiodothyronine (T{sub 3}) receptor may be a mechanism involved in the thermoregulatory action of T{sub 3} at the nuclear level. To study this, the authors analyzed changes in T{sub 3} nuclear receptor kinetics in cold exposed swine and compared them with similar animals housed at thermoneutral temperature. Receptors were from isolated nuclear extracts of circulating mononuclear leukocytes (MNL). Scatchard analysis indicates the presence of a single class of binding sites. The authors were unable to detect differences in the equilibrium dissociation constant (Kd) or the maximum binding capacity (MBC, fmol/up DNA) between the two groups. The Kd for T{sub 3} in the control group was 1.17 {plus minus} 0.11 nmol/L and 1.25 {plus minus} 0.19 nmol/L in the cold exposed group. The MBC was 0.43 {plus minus} 0.04 fmol/ug DNA in the control group and 0.40 {plus minus} 0.06 fmol/L in the cold exposed group. In competition studies using thyroid hormone analogues, 10{sup {minus}7} M reverse T{sub 3} and 3,5-diiodothyronine resulted in approximately 50% displacement from the porcine receptor. TRIAC and L-T{sub 4} had no effect at 10{sup {minus}7} M. The porcine values for both Kd and MBC are similar to those previously reported for human MNL. Although T{sub 3} production and serum T{sub 3} values in the cold exposed group are nearly double the control group (Reed et al., FASEB 1991), continuous short-term cold exposure had no significant effect on MNL nuclear T{sub 3} receptor kinetics.

  1. Graphical method for forecasting radiation exposure from multi-aged fallout from nuclear weapons

    SciTech Connect

    Haaland, C.M.

    1986-06-01

    After a nuclear attack it may be necessary for emergency workers, such as firemen, utility workers and medical personnel, to perform urgent tasks in areas highly contaminated by radioactive fallout. To assist the control of radiation exposure of these workers, it will be useful to provide means to forecast radiation exposures both inside and outside the fallout shelter. The method described in this paper is intended for use during the first few days to weeks after the attack, after which time more sophisticated methods may become available. This method requires only a radiation-rate meter, special graph paper, and a timepiece. Communications with Emergency Operating Centers or other sources of information are not necessary. The method permits the determination of the age of fallout and future exposure rates for a location that might be subjected to a number of different fallout clouds, without requiring knowledge of the weapon yields or times of detonation. This method will provide results with less accuracy if different-aged fallout clouds arrive simultaneously. The method is self-correcting so that if the actual decay rate is different than that which is assumed, the forecasted rates will have less error than results obtained by previous methods.

  2. A graphical method for forecasting radiation exposure from multi-aged fallout from nuclear weapons.

    PubMed

    Haaland, C M

    1986-06-01

    After a nuclear attack it may be necessary for emergency workers, such as firemen, utility workers and medical personnel, to perform urgent tasks in areas highly contaminated by radioactive fallout. To assist the control of radiation exposure of these workers, it will be useful to provide means to forecast radiation exposures both inside and outside the fallout shelter. The method described in this paper is intended for use during the first few days to weeks after the attack, after which time more sophisticated methods may become available. This method requires only a radiation-rate meter, special graph paper, and a timepiece. Communications with Emergency Operating Centers or other sources of information are not necessary. The method permits the determination of the age of fallout and future exposure rates for a location that might be subjected to a number of different fallout clouds, without requiring knowledge of the weapon yields or times of detonation. This method will provide results with less accuracy if different-aged fallout clouds arrive simultaneously. The method is self-correcting so that if the actual decay rate is different than that which is assumed, the forecasted rates will have less error than results obtained by previous methods.

  3. The relationship of thyroid cancer with radiation exposure from nuclear weapon testing in the Marshall Islands.

    PubMed

    Takahashi, Tatsuya; Schoemaker, Minouk J; Trott, Klaus R; Simon, Steven L; Fujimori, Keisei; Nakashima, Noriaki; Fukao, Akira; Saito, Hiroshi

    2003-03-01

    The US nuclear weapons testing program in the Pacific conducted between 1946 and 1958 resulted in radiation exposure in the Marshall Islands. The potentially widespread radiation exposure from radio-iodines of fallout has raised concerns about the risk of thyroid cancer in the Marshallese population. The most serious exposures and its health hazards resulted from the hydrogen-thermonuclear bomb test, the Castle BRAVO, on March 1, 1954. Between 1993 and 1997, we screened 3,709 Marshallese for thyroid disease who were born before the BRAVO test. It was 60% of the entire population at risk and who were still alive at the time of our examinations. We diagnosed 30 thyroid cancers and found 27 other study participants who had been operated for thyroid cancer before our screening in this group. Fifty-seven Marshallese born before 1954 (1.5%) had thyroid cancer or had been operated for thyroid cancer. Nearly all (92%) of these cancers were papillary carcinoma. We derived estimates of individual thyroid dose proxy from the BRAVO test in 1954 on the basis of published age-specific doses estimated on Utirik atoll and 137Cs deposition levels on the atolls where the participants came from. There was suggestive evidence that the prevalence of thyroid cancer increased with category of estimated dose to the thyroid.

  4. Acute health effects associated with exposure to volcanic air pollution (vog) from increased activity at Kilauea Volcano in 2008.

    PubMed

    Longo, Bernadette M; Yang, Wei; Green, Joshua B; Crosby, Frederick L; Crosby, Vickie L

    2010-01-01

    In 2008, the Kilauea Volcano on the island of Hawai'i increased eruption activity and emissions of sulfurous volcanic air pollution called vog. The purpose of this study was to promptly assess for a relative increase in cases of medically diagnosed acute illnesses in an exposed Hawaiian community. Using a within-clinic retrospective cohort design, comparisons were made for visits of acute illnesses during the 14 wk prior to the increased volcanic emissions (low exposure) to 14 wk of high vog exposure when ambient sulfur dioxide was threefold higher and averaged 75 parts per billion volume per day. Logistic regression analysis estimated effect measures between the low- and high-exposure cohorts for age, gender, race, and smoking status. There were statistically significant positive associations between high vog exposure and visits for medically diagnosed cough, headache, acute pharyngitis, and acute airway problems. More than a sixfold increase in odds was estimated for visits with acute airway problems, primarily experienced by young Pacific Islanders. These findings suggest that the elevated volcanic emissions in 2008 were associated with increased morbidity of acute illnesses in age and racial subgroups of the general Hawaiian population. Continued investigation is crucial to fully assess the health impact of this natural source of sulfurous air pollution. Culturally appropriate primary- and secondary-level health prevention initiatives are recommended for populations in Hawai'i and volcanically active areas worldwide.

  5. Urinary metabolic signatures and early triage of acute radiation exposure in rat model.

    PubMed

    Zhao, Mingxiao; Lau, Kim Kt; Zhou, Xian; Wu, Jianfang; Yang, Jun; Wang, Chang

    2017-03-28

    After a large-scale radiological accident, early-response biomarkers to assess radiation exposure over a broad dose range are not only the basis of rapid radiation triage, but are also the key to the rational use of limited medical resources and to the improvement of treatment efficiency. Because of its high throughput, rapid assays and minimally invasive sample collection, metabolomics has been applied to research into radiation exposure biomarkers in recent years. Due to the complexity of radiobiological effects, most of the potential biomarkers are both dose-dependent and time-dependent. In reality, it is very difficult to find a single biomarker that is both sensitive and specific in a given radiation exposure scenario. Therefore, a multi-parameters approach for radiation exposure assessment is more realistic in real nuclear accidents. In this study, untargeted metabolomic profiling based on gas chromatography-mass spectrometry (GC-MS) and targeted amino acid profiling based on LC-MS/MS were combined to investigate early urinary metabolite responses within 48 h post-exposure in a rat model. A few of the key early-response metabolites for radiation exposure were identified, which revealed the most relevant metabolic pathways. Furthermore, a panel of potential urinary biomarkers was selected through a multi-criteria approach and applied to early triage following irradiation. Our study suggests that it is feasible to use a multi-parameters approach to triage radiation damage, and the urinary excretion levels of the relevant metabolites provide insights into radiation damage and repair.

  6. Evidence Report: Risk of Acute and Late Central Nervous System Effects from Radiation Exposure

    NASA Technical Reports Server (NTRS)

    Nelson, Gregory A.; Simonsen, Lisa; Huff, Janice L.

    2016-01-01

    Possible acute and late risks to the central nervous system (CNS) from galactic cosmic rays (GCR) and solar particle events (SPE) are concerns for human exploration of space. Acute CNS risks may include: altered cognitive function, reduced motor function, and behavioral changes, all of which may affect performance and human health. Late CNS risks may include neurological disorders such as Alzheimer's disease (AD), dementia and premature aging. Although detrimental CNS changes are observed in humans treated with high-dose radiation (e.g., gamma rays and 9 protons) for cancer and are supported by experimental evidence showing neurocognitive and behavioral effects in animal models, the significance of these results on the morbidity to astronauts has not been elucidated. There is a lack of human epidemiology data on which to base CNS risk estimates; therefore, risk projection based on scaling to human data, as done for cancer risk, is not possible for CNS risks. Research specific to the spaceflight environment using animal and cell models must be compiled to quantify the magnitude of CNS changes in order to estimate this risk and to establish validity of the current permissible exposure limits (PELs). In addition, the impact of radiation exposure in combination with individual sensitivity or other space flight factors, as well as assessment of the need for biological/pharmaceutical countermeasures, will be considered after further definition of CNS risk occurs.

  7. Transcriptional Response to Acute Thermal Exposure in Juvenile Chinook Salmon Determined by RNAseq

    PubMed Central

    Tomalty, Katharine M. H.; Meek, Mariah H.; Stephens, Molly R.; Rincón, Gonzalo; Fangue, Nann A.; May, Bernie P.; Baerwald, Melinda R.

    2015-01-01

    Thermal exposure is a serious and growing challenge facing fish species worldwide. Chinook salmon (Oncorhynchus tshawytscha) living in the southern portion of their native range are particularly likely to encounter warmer water due to a confluence of factors. River alterations have increased the likelihood that juveniles will be exposed to warm water temperatures during their freshwater life stage, which can negatively impact survival, growth, and development and pose a threat to dwindling salmon populations. To better understand how acute thermal exposure affects the biology of salmon, we performed a transcriptional analysis of gill tissue from Chinook salmon juveniles reared at 12° and exposed acutely to water temperatures ranging from ideal to potentially lethal (12° to 25°). Reverse-transcribed RNA libraries were sequenced on the Illumina HiSeq2000 platform and a de novo reference transcriptome was created. Differentially expressed transcripts were annotated using Blast2GO and relevant gene clusters were identified. In addition to a high degree of downregulation of a wide range of genes, we found upregulation of genes involved in protein folding/rescue, protein degradation, cell death, oxidative stress, metabolism, inflammation/immunity, transcription/translation, ion transport, cell cycle/growth, cell signaling, cellular trafficking, and structure/cytoskeleton. These results demonstrate the complex multi-modal cellular response to thermal stress in juvenile salmon. PMID:25911227

  8. Evidence Report: Risk of Acute and Late Central Nervous System Effects from Radiation Exposure

    NASA Technical Reports Server (NTRS)

    Nelson, Gregory A.; Simonsen, Lisa; Huff, Janice L.

    2015-01-01

    Possible acute and late risks to the central nervous system (CNS) from galactic cosmic rays (GCR) and solar particle events (SPE) are a documented concern for human exploration of space. Acute CNS risks include: altered cognitive function, reduced motor function, and behavioral changes, all of which may affect performance and human health. Late CNS risks include neurological disorders such as Alzheimer's disease (AD), dementia and premature aging. Although detrimental CNS changes are observed in humans treated with high-dose radiation (e.g., gamma rays and protons) for cancer and are supported by experimental evidence showing neurocognitive and behavioral effects in animal models, the significance of these results on the morbidity to astronauts has not been elucidated. There is a lack of human epidemiology data on which to base CNS risk estimates; therefore, risk projection based on scaling to human data, as done for cancer risk, is not possible for CNS risks. Research specific to the spaceflight environment using animal and cell models must be compiled to quantify the magnitude of CNS changes in order to estimate this risk and to establish validity of the current permissible exposure limits (PELs). In addition, the impact of radiation exposure in combination with individual sensitivity or other space flight factors, as well as assessment of the need for biological/pharmaceutical countermeasures, will be considered after further definition of CNS risk occurs.

  9. Acute nonlymphocytic leukemia and residential exposure to power frequency magnetic fields

    SciTech Connect

    Severson, R.K.

    1986-01-01

    A population-based case-control study of adult acute nonlymphocytic leukemia (ANLL) and residential exposure to power frequency magnetic fields was conducted in King, Pierce and Snohomish Counties in Washington state. Of 164 cases who were diagnosed from January 1, 1981 through December 31, 1984, 114 were interviewed. Controls were selected from the study area on the basis of random digit dialing and frequency matched to the cases by age and sex. Analyses were undertaken to evaluate whether exposure to high levels of power frequency magnetic fields in the residence were associated with an increased risk of ANLL. Neither the directly measured magnetic fields nor the surrogate values based on the wiring configurations were associated with ANLL. Additional analyses suggested that persons with prior allergies were at decreased risk of acute myelocytic leukemia (AML). Also, persons with prior autoimmune diseases were at increased risk of AML. The increase in AML risk in rheumatoid arthritics was of borderline statistical significance. Finally, cigarette smoking was associated with an increased risk of AML. The risk of AML increased significantly with the number of years of cigarette smoking.

  10. Cellular and molecular mechanisms of acute exposure to sulfur mustard: a systematic review.

    PubMed

    Nourani, Mohammad Reza; Mahmoodzadeh Hosseini, Hamideh; Azimzadeh Jamalkandi, Sadegh; Imani Fooladi, Abbas Ali

    2017-04-01

    Mustard gas (e.g. sulfur mustard (SM)) has been used as a chemical agent in several battles and is still a potential worldwide menace. Besides local absorption, particularly in the skin, eyes and lungs, systemic spread of the agent also has detrimental effects on gonads, bone marrow and nervous system. Moreover, chronic exposure of SM to respiratory system causes death. Inducing oxidative stress, and disturbing DNA and tissue repair systems, inflammation and cell death signaling pathways have been introduced as molecular mechanisms of the injury. In this systematic review, more than 1200 (2000-2014) articles focusing on gross or molecular pathological reports in the acute phase of the respiratory injury after SM exposure were reviewed, followed by two different layers of gross and molecular pathological data (clinic and laboratory) integrated together in a spatio-temporal order. Role of epithelial, neutrophil and macrophage cells and three signaling pathways of inflammation, oxidative stress and cell death are covered in details. Our results propose a critical role of interleukin-17 producing cells in acute and chronic inflammatory responses.

  11. Acute alcohol exposure markedly influences male fertility and fetal outcome in the male rat.

    PubMed

    Cicero, T J; Nock, B; O'Connor, L; Adams, M L; Sewing, B N; Meyer, E R

    1994-01-01

    Although it is recognized that drugs ingested by pregnant females produce marked cognitive and physiological deficits in their offspring, the possibility that paternal exposure to drugs prior to mating may have adverse effects on fertility and fetal outcome has not received much attention. The purpose of the present studies was to examine whether a single, acute exposure to alcohol influences the subsequent ability of adult male rats to mate and produce healthy and viable litters. Our results showed that a relatively large dose of alcohol 24 hours prior to breeding had little effect on the mating behavior of male rats, but there were markedly fewer pregnancies in females mated with alcohol-exposed male rats than in controls. Of equal importance, we found that, even when conception occurred and live births were produced, there were striking differences in fetal outcome. Alcohol-treated males sired many fewer pups than control males and there was a markedly enhanced mortality rate in their offspring. Collectively, these data suggest that acute paternal alcohol administration 24 hours prior to breeding does not affect mating behavior, but results in a greatly diminished fertility rate and fewer and less viable offspring. These studies suggest that paternal alcohol use may be as important as maternal alcohol abuse as a negative variable in pregnancy and fetal outcome.

  12. [Measures against Radiation Exposure Due to Large-Scale Nuclear Accident in Distant Place--Radioactive Materials in Nagasaki from Fukushima Daiichi Nuclear Power Plant].

    PubMed

    Yuan, Jun; Sera, Koichiro; Takatsuji, Toshihiro

    2015-01-01

    To investigate human health effects of radiation exposure due to possible future nuclear accidents in distant places and other various findings of analysis of the radioactive materials contaminating the atmosphere of Nagasaki due to the Fukushima Daiichi Nuclear Power Plant accident. The concentrations of radioactive materials in aerosols in the atmosphere of Nagasaki were measured using a germanium semiconductor detector from March 2011 to March 2013. Internal exposure dose was calculated in accordance with ICRP Publ. 72. Air trajectories were analyzed using NOAA and METEX web-based systems. (134)Cs and (137)Cs were repeatedly detected. The air trajectory analysis showed that (134)Cs and (137)Cs flew directly from the Fukushima Daiichi Nuclear Power Plant from March to April 2011. However, the direct air trajectories were rarely detected after this period even when (134)Cs and (137)Cs were detected after this period. The activity ratios ((134)Cs/(137)Cs) of almost all the samples converted to those in March 2011 were about unity. This strongly suggests that the (134)Cs and (137)Cs detected mainly originated from the Fukushima Daiichi Nuclear Power Plant accident in March 2011. Although the (134)Cs and (137)Cs concentrations per air volume were very low and the human health effects of internal exposure via inhalation is expected to be negligible, the specific activities (concentrations per aerosol mass) were relatively high. It was found that possible future nuclear accidents may cause severe radioactive contaminations, which may require radiation exposure control of farm goods to more than 1000 km from places of nuclear accidents.

  13. Acute kidney injury secondary to exposure to insecticides used for bedbug (Cimex lectularis) control.

    PubMed

    Bashir, Babar; Sharma, Shree G; Stein, Harold D; Sirota, Robert A; D'Agati, Vivette D

    2013-11-01

    Bedbug (Cimex lectularis) infestation is becoming a worldwide epidemic due to the emergence of insecticide-resistant strains. Pyrethroids are approved by the US Environmental Protection Agency for use against bedbugs and are considered minimally toxic to humans, with known respiratory, neurologic, and gastrointestinal effects. We present the first reported case of pyrethroid-induced toxic acute tubular necrosis (ATN). A 66-year-old healthy woman receiving no prior nephrotoxic medications presented with extreme weakness, decreased urine output, and acute kidney injury. She had administered multiple applications of a bedbug spray (permethrin) and a fogger (pyrethrin), exceeding the manufacturer's recommended amounts. She was found to have severe nonoliguric acute kidney injury associated with profound hypokalemia. Kidney biopsy revealed toxic ATN with extensive tubular degenerative changes and cytoplasmic vacuolization. With conservative management, serum creatinine level decreased from 13.0 mg/dL (estimated glomerular filtration rate, 3 mL/min/1.73 m(2)) to 1.67 mg/dL (estimated glomerular filtration rate, 37 mL/min/1.73 m(2)) within 6 weeks. Literature review uncovered no prior report of pyrethroid insecticide-induced ATN in humans, although there are reports of ATN with similar tubular vacuolization in rats exposed to this agent. Bedbug insecticides containing pyrethroids should be used with caution due to the potential development of toxic ATN after prolonged exposure.

  14. Acute exposure to apolipoprotein A1 inhibits macrophage chemotaxis in vitro and monocyte recruitment in vivo

    PubMed Central

    Iqbal, Asif J; Barrett, Tessa J; Taylor, Lewis; McNeill, Eileen; Manmadhan, Arun; Recio, Carlota; Carmineri, Alfredo; Brodermann, Maximillian H; White, Gemma E; Cooper, Dianne; DiDonato, Joseph A; Zamanian-Daryoush, Maryam; Hazen, Stanley L; Channon, Keith M

    2016-01-01

    Apolipoprotein A1 (apoA1) is the major protein component of high-density lipoprotein (HDL) and has well documented anti-inflammatory properties. To better understand the cellular and molecular basis of the anti-inflammatory actions of apoA1, we explored the effect of acute human apoA1 exposure on the migratory capacity of monocyte-derived cells in vitro and in vivo. Acute (20–60 min) apoA1 treatment induced a substantial (50–90%) reduction in macrophage chemotaxis to a range of chemoattractants. This acute treatment was anti-inflammatory in vivo as shown by pre-treatment of monocytes prior to adoptive transfer into an on-going murine peritonitis model. We find that apoA1 rapidly disrupts membrane lipid rafts, and as a consequence, dampens the PI3K/Akt signalling pathway that coordinates reorganization of the actin cytoskeleton and cell migration. Our data strengthen the evidence base for therapeutic apoA1 infusions in situations where reduced monocyte recruitment to sites of inflammation could have beneficial outcomes. DOI: http://dx.doi.org/10.7554/eLife.15190.001 PMID:27572261

  15. The effect of acute exposure to hyperbaric oxygen on respiratory system mechanics in the rat.

    PubMed

    Rubini, Alessandro; Porzionato, Andrea; Zara, Susi; Cataldi, Amelia; Garetto, Giacomo; Bosco, Gerardo

    2013-10-01

    This study was designed to investigate the possible effects of acute hyperbaric hyperoxia on respiratory mechanics of anaesthetised, positive-pressure ventilated rats. We measured respiratory mechanics by the end-inflation occlusion method in nine rats previously acutely exposed to hyperbaric hyperoxia in a standard fashion. The method allows the measurements of respiratory system elastance and of both the "ohmic" and of the viscoelastic components of airway resistance, which respectively depend on the newtonian pressure dissipation due to the ohmic airway resistance to air flow, and on the viscoelastic pressure dissipation caused by respiratory system tissues stress-relaxation. The activities of inducible and endothelial NO-synthase in the lung's tissues (iNOS and eNOS respectively) also were investigated. Data were compared with those obtained in control animals. We found that the exposure to hyperbaric hyperoxia increased respiratory system elastance and both the "ohmic" and viscoelastic components of inspiratory resistances. These changes were accompanied by increased iNOS but not eNOS activities. Hyperbaric hyperoxia was shown to acutely induce detrimental effects on respiratory mechanics. A possible causative role was suggested for increased nitrogen reactive species production because of increased iNOS activity.

  16. Acute Manipulation of Diacylglycerol Reveals Roles in Nuclear Envelope Assembly & Endoplasmic Reticulum Morphology

    PubMed Central

    Peddie, Christopher J.; Chung, Gary H. C.; Wang, Alan; Yeh, Karen; Jethwa, Nirmal; Zhang, Qifeng; Wakelam, Michael J. O.; Woscholski, Rudiger; Byrne, Richard D.; Collinson, Lucy M.; Poccia, Dominic L.; Larijani, Banafshé

    2012-01-01

    The functions and morphology of cellular membranes are intimately related and depend not only on their protein content but also on the repertoire of lipids that comprise them. In the absence of in vivo data on lipid asymmetry in endomembranes, it has been argued that motors, scaffolding proteins or integral membrane proteins rather than non-lamellar bilayer lipids such as diacylglycerol (DAG), are responsible for shaping of organelles, local membrane curvature and fusion. The effects of direct alteration of levels of such lipids remain predominantly uninvestigated. Diacylglycerol (DAG) is a well documented second messenger. Here we demonstrate two additional conserved functions of DAG: a structural role in organelle morphology, and a role in localised extreme membrane curvature required for fusion for which proteins alone are insufficient. Acute and inducible DAG depletion results in failure of the nuclear envelope (NE) to reform at mitosis and reorganisation of the ER into multi-lamellar sheets as revealed by correlative light and electron microscopy and 3D reconstructions. Remarkably, depleted cells divide without a complete NE, and unless rescued by 1,2 or 1,3 DAG soon die. Attenuation of DAG levels by enzyme microinjection into echinoderm eggs and embryos also results in alterations of ER morphology and nuclear membrane fusion. Our findings demonstrate that DAG is an in vivo modulator of organelle morphology in mammalian and echinoderm cells, indicating a fundamental role conserved across the deuterostome superphylum. PMID:23227247

  17. Work-Time Exposure and Acute Injuries in Inshore Lobstermen of the Northeast United States.

    PubMed

    Fulmer, Scott; Buchholz, Bryan; Jenkins, Paul; Scribani, Melissa

    2016-01-01

    The objective of this study was to inform efforts to reduce risk for musculoskeletal disorders among commercial lobstermen by characterizing and quantifying injuries that occur to people while harvesting lobsters commercially in the Northeast United States. This study aimed to estimate a denominator of exposure to lobstering in full-time equivalents (FTE), to estimate a fatality rate, and to calculate incidence rates for acute injuries within the sample population. Captains were randomly selected from those licensed to fish in Maine and Massachusetts. Data on work exposure and injuries with rapid onset that occurred on the boat ("acute injuries") were collected using a survey, which was administered quarterly via phone or face-to-face interview with the captain. The quarterly survey assessed the number of weeks worked during the quarter, average crew size, number of trips per week, and average trip length in hours. In addition, this survey captured relevant information (body segment affected, type of injury, and whether treatment was received) on all acute injuries occurring during the quarter. FTE were estimated using fishermen days and fishermen hours. The annual FTE estimated using days was 2,557 and using hours was 2,855. As expected, the summer months (3rd quarter) had the highest FTE and the winter (1st quarter) the lowest FTE. Fall (4th quarter) and spring (2nd quarter) ranked second and third, respectively. The incidence rates for all injuries (49.7/100 FTE) and injuries requiring treatment (15.0/100 FTE) were much higher than those reported in other studies of fishing that used Coast Guard data.

  18. Acute radiation enteritis caused by dose-dependent radiation exposure in dogs: experimental research.

    PubMed

    Xu, Wenda; Chen, Jiang; Xu, Liu; Li, Hongyu; Guo, Xiaozhong

    2014-12-01

    Accidental or intended radiation exposure in mass casualty settings presents a serious and on-going threat. The development of mitigating and treating agents requires appropriate animal models. Unfortunately, the majority of research on radiation enteritis in animals has lacked specific assessments and targeted therapy. Our study showed beagle dogs, treated by intensity-modulated radiation therapy (IMRT) for abdominal irradiation, were administered single X-ray doses of 8-30 Gy. The degree of intestinal tract injury for all of the animals after radiation exposure was evaluated with regard to clinical syndrome, endoscopic findings, histological features, and intestinal function. The range of single doses (8 Gy, 10-14 Gy, and 16-30 Gy) represented the degree of injury (mild, moderate, and severe, respectively). Acute radiation enteritis included clinical syndrome with fever, vomiting, diarrhea, hemafecia, and weight loss; typical endoscopic findings included edema, bleeding, mucosal abrasions, and ulcers; and intestinal biopsy results revealed mucosal necrosis, erosion, and loss, inflammatory cell infiltration, hemorrhage, and congestion. Changes in serum diamine oxides (DAOs) and d-xylose represented intestinal barrier function and absorption function, respectively, and correlated with the extent of damage (P < 0.05 and P < 0.05, respectively). We successfully developed a dog model of acute radiation enteritis, thus obtaining a relatively objective evaluation of intestinal tract injury based on clinical performance and laboratory examination. The method of assessment of the degree of intestinal tract injury after abdominal irradiation could be beneficial in the development of novel and effective therapeutic strategies for acute radiation enteritis.

  19. Abundance of Plasma Antioxidant Proteins Confers Tolerance to Acute Hypobaric Hypoxia Exposure

    PubMed Central

    Padhy, Gayatri; Sethy, Niroj Kumar; Ganju, Lilly

    2013-01-01

    Abstract Padhy, Gayatri, Niroj Kumar Sethy, Lilly Ganju, and Kalpana Bhargava. Abundance of plasma antioxidant proteins confers tolerance to acute hypobaric hypoxia exposure. High Alt Med Biol 14:289–297, 2013—Systematic identification of molecular signatures for hypobaric hypoxia can aid in better understanding of human adaptation to high altitude. In an attempt to identify proteins promoting hypoxia tolerance during acute exposure to high altitude, we screened and identified hypoxia tolerant and susceptible rats based on hyperventilation time to a simulated altitude of 32,000 ft (9754 m). The hypoxia tolerance was further validated by estimating 8-isoprotane levels and protein carbonyls, which revealed that hypoxia tolerant rats possessed significant lower plasma levels as compared to susceptible rats. We used a comparative plasma proteome profiling approach using 2-dimensional gel electrophoresis (2-DGE) combined with MALDI TOF/TOF for both groups, along with an hypoxic control group. This resulted in the identification of 19 differentially expressed proteins. Seven proteins (TTR, GPx-3, PON1, Rab-3D, CLC11, CRP, and Hp) were upregulated in hypoxia tolerant rats, while apolipoprotein A-I (APOA1) was upregulated in hypoxia susceptible rats. We further confirmed the consistent higher expression levels of three antioxidant proteins (PON1, TTR, and GPx-3) in hypoxia-tolerant animals using ELISA and immunoblotting. Collectively, these proteomics-based results highlight the role of antioxidant enzymes in conferring hypoxia tolerance during acute hypobaric hypoxia. The expression of these antioxidant enzymes could be used as putative biomarkers for screening altitude adaptation as well as aiding in better management of altered oxygen pathophysiologies. PMID:24067188

  20. Minimal Internal Radiation Exposure in Residents Living South of the Fukushima Daiichi Nuclear Power Plant Disaster.

    PubMed

    Akiyama, Junichi; Kato, Shigeaki; Tsubokura, Masaharu; Mori, Jinichi; Tanimoto, Tetsuya; Abe, Koichiro; Sakai, Shuji; Hayano, Ryugo; Tokiwa, Michio; Shimmura, Hiroaki

    2015-01-01

    Following the Fukushima nuclear power plant disaster, assessment of internal radiation exposure was indispensable to predict radiation-related health threats to residents of neighboring areas. Although many evaluations of internal radiation in residents living north and west of the crippled Fukushima nuclear power plant are available, there is little information on residents living in areas south of the plant, which were similarly affected by radio-contamination from the disaster. To assess the internal radio-contamination in residents living in affected areas to the south of the plant or who were evacuated into Iwaki city, a whole body counter (WBC) screening program of internal radio-contamination was performed on visitors to the Jyoban hospital in Iwaki city, which experienced less contamination than southern areas adjacent to the nuclear plant. The study included 9,206 volunteer subjects, of whom 6,446 were schoolchildren aged 4-15 years. Measurements began one year after the incident and were carried out over the course of two years. Early in the screening period only two schoolchildren showed Cs-137 levels that were over the detection limit (250 Bq/body), although their Cs-134 levels were below the detection limit (220 Bq/body). Among the 2,760 adults tested, 35 (1.3%) had detectable internal radio-contamination, but only for Cs-137 (range: 250 Bq/body to 859 Bq/body), and not Cs-134. Of these 35 subjects, nearly all (34/35) showed elevated Cs-137 levels only during the first year of the screening. With the exception of potassium 40, no other radionuclides were detected during the screening period. The maximum annual effective dose calculated from the detected Cs-137 levels was 0.029 and 0.028 mSv/year for the schoolchildren and adults, respectively, which is far below the 1 mSv/year limit set by the government of Japan. Although the data for radiation exposure during the most critical first year after the incident are unavailable due to a lack of systemic

  1. Risk Perception of Radiation Exposure of Villagers Living Near the Semipalatinsk Nuclear Test Site

    NASA Astrophysics Data System (ADS)

    Purvis-Roberts, K. L.

    2006-12-01

    Connecting scientific data to societal needs is particularly important with the complex environmental issues that face us in the near future, such as global warming and natural hazards. Once the scientific data is collected and analyzed, dissemination of the results needs to be communicated to the public in a way that can be easily understood without glossing over the complexity of the issue. An interesting case study derives from the primary nuclear test site for the former Soviet Union, located near the city of Semipalatinsk, Kazakhstan. Villagers living directly adjacent to the Semipalatinsk Nuclear Test Site (SNTS) were exposed continuously to radioactive clouds from atmospheric, above ground and underground nuclear tests. The people living in the region are still exposed to low levels of radiation through the environmental contamination of their food and water and have experienced a higher incidence of cancers and birth defects than people living in other regions of the country. A database of historical environmental data was collected throughout the nuclear testing period by the Soviet government, tracking radiation concentrations through food, water, and soil samples around the SNTS, but this environmental data was never shared with the villagers. In fact, only after the Soviet Union fell apart in 1989 did the people discover that they had been exposed to radiation during the past 40 years. Through preliminary interviews with villagers, physicians, and scientists who live near the SNTS, it was discovered that the three groups viewed the risk of radiation exposure very differently. By developing a risk perception survey to understand how the different groups perceived radiation risk, and then comparing the scientific data to the survey results, a better way to communicate the risk could be developed. The risk perception survey was given to over 800 people in East Kazakhstan Oblast, including villagers living near the SNTS, scientists who study the

  2. Minimal Internal Radiation Exposure in Residents Living South of the Fukushima Daiichi Nuclear Power Plant Disaster

    PubMed Central

    Akiyama, Junichi; Kato, Shigeaki; Tsubokura, Masaharu; Mori, Jinichi; Tanimoto, Tetsuya; Abe, Koichiro; Sakai, Shuji; Hayano, Ryugo; Tokiwa, Michio; Shimmura, Hiroaki

    2015-01-01

    Following the Fukushima nuclear power plant disaster, assessment of internal radiation exposure was indispensable to predict radiation-related health threats to residents of neighboring areas. Although many evaluations of internal radiation in residents living north and west of the crippled Fukushima nuclear power plant are available, there is little information on residents living in areas south of the plant, which were similarly affected by radio-contamination from the disaster. To assess the internal radio-contamination in residents living in affected areas to the south of the plant or who were evacuated into Iwaki city, a whole body counter (WBC) screening program of internal radio-contamination was performed on visitors to the Jyoban hospital in Iwaki city, which experienced less contamination than southern areas adjacent to the nuclear plant. The study included 9,206 volunteer subjects, of whom 6,446 were schoolchildren aged 4–15 years. Measurements began one year after the incident and were carried out over the course of two years. Early in the screening period only two schoolchildren showed Cs-137 levels that were over the detection limit (250 Bq/body), although their Cs-134 levels were below the detection limit (220 Bq/body). Among the 2,760 adults tested, 35 (1.3%) had detectable internal radio-contamination, but only for Cs-137 (range: 250 Bq/body to 859 Bq/body), and not Cs-134. Of these 35 subjects, nearly all (34/35) showed elevated Cs-137 levels only during the first year of the screening. With the exception of potassium 40, no other radionuclides were detected during the screening period. The maximum annual effective dose calculated from the detected Cs-137 levels was 0.029 and 0.028 mSv/year for the schoolchildren and adults, respectively, which is far below the 1 mSv/year limit set by the government of Japan. Although the data for radiation exposure during the most critical first year after the incident are unavailable due to a lack of systemic

  3. Neurochemical dynamics of acute orofacial pain in the human trigeminal brainstem nuclear complex.

    PubMed

    de Matos, Nuno M P; Hock, Andreas; Wyss, Michael; Ettlin, Dominik A; Brügger, Mike

    2017-09-04

    The trigeminal brainstem sensory nuclear complex is the first central relay structure mediating orofacial somatosensory and nociceptive perception. Animal studies suggest a substantial involvement of neurochemical alterations at such basal CNS levels in acute and chronic pain processing. Translating this animal based knowledge to humans is challenging. Human related examining of brainstem functions are challenged by MR related peculiarities as well as applicability aspects of experimentally standardized paradigms. Based on our experience with an MR compatible human orofacial pain model, the aims of the present study were twofold: 1) from a technical perspective, the evaluation of proton magnetic resonance spectroscopy at 3 T regarding measurement accuracy of neurochemical profiles in this small brainstem nuclear complex and 2) the examination of possible neurochemical alterations induced by an experimental orofacial pain model. Data from 13 healthy volunteers aged 19-46 years were analyzed and revealed high quality spectra with significant reductions in total N-acetylaspartate (N-acetylaspartate + N-acetylaspartylglutamate) (-3.7%, p = 0.009) and GABA (-10.88%, p = 0.041) during the pain condition. These results might reflect contributions of N-acetylaspartate and N-acetylaspartylglutamate in neuronal activity-dependent physiologic processes and/or excitatory neurotransmission, whereas changes in GABA might indicate towards a reduction in tonic GABAergic functioning during nociceptive signaling. Summarized, the present study indicates the applicability of (1)H-MRS to obtain neurochemical dynamics within the human trigeminal brainstem sensory nuclear complex. Further developments are needed to pave the way towards bridging important animal based knowledge with human research to understand the neurochemistry of orofacial nociception and pain. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. [The NSI (Noise Sensitivity Index)--a method for the demonstration of acute physical symptoms in noise exposure and combination exposure].

    PubMed

    Meister, A; Bening, Y; Brumm, L M

    1989-01-01

    The NSI (Noise Sensitive Index) is a method suitable for the single or repeated recording of acute, subjectively perceived bodily complaints caused by exposure against noise alone or combined with additional physical factors (e.g. physical load, high temperature) during the lapse of exposure. The paper describes the application of NSI in 6 experimental investigations. The results are indicative regarding their dependence on components of exposure and personality. If certain rules are taken into consideration, application, scoring and interpretation of NSI is easy, not very time consuming, and profitable.

  5. Sustained impairment of respiratory function and swim performance following acute oil exposure in a coastal marine fish.

    PubMed

    Johansen, J L; Esbaugh, A J

    2017-06-01

    Acute exposure to crude oil polycyclic aromatic hydrocarbons (PAH) can severely impair cardiorespiratory function and swim performance of larval fish; however, the effects of acute oil exposure on later life stages and the capacity for subsequent recovery is less clear. Red drum (Sciaenops ocellatus) is an economically important apex predator native to the Gulf of Mexico, which was directly exposed to the 2010 Deep Water Horizon (DWH) oil spill. Here we examine impact and recovery of young adult red drum from exposure to concentrations of 0, 4.1, and 12.1μgL(-1) ΣPAH50 naturally weathered oil-water accommodated fractions (geometric mean), which are well within the range of concentrations measured during the DWH incident. We focused on aerobic scope (ASc), burst- and critical swimming speeds (Uburst and Ucrit), cost of transport (COT), as well as the capacity to repay oxygen debt following exhaustive exercise (EPOC), which are critical parameters for success of all life stages of fishes. A 24h acute exposure to 4.1μgL(-1) ΣPAH caused a significant 9.7 and 12.6% reduction of Uburst and Ucrit respectively, but no change in ASc, COT or EPOC, highlighting a decoupled effect on the respiratory and swimming systems. A higher exposure concentration, 12.1μgL(-1) ΣPAH, caused an 8.6 and 8.4% impairment of Uburst and Ucrit, as well as an 18.4% reduction in ASc. These impairments persisted six weeks post-exposure, suggesting that recorded impacts are entrenched. Large predatory fishes are critically dependent on the cardiorespiratory and swimming systems for ecological fitness, and long-term impairment of performance due to acute oil exposure suggests that even acute exposure events may have long lasting impacts on the ecological fitness of affected populations. Copyright © 2017. Published by Elsevier B.V.

  6. Combined Exposure to Simulated Microgravity and Acute or Chronic Radiation Reduces Neuronal Network Integrity and Survival

    PubMed Central

    Quintens, Roel; Samari, Nada; de Saint-Georges, Louis; van Oostveldt, Patrick; Baatout, Sarah; Benotmane, Mohammed Abderrafi

    2016-01-01

    During orbital or interplanetary space flights, astronauts are exposed to cosmic radiations and microgravity. However, most earth-based studies on the potential health risks of space conditions have investigated the effects of these two conditions separately. This study aimed at assessing the combined effect of radiation exposure and microgravity on neuronal morphology and survival in vitro. In particular, we investigated the effects of simulated microgravity after acute (X-rays) or during chronic (Californium-252) exposure to ionizing radiation using mouse mature neuron cultures. Acute exposure to low (0.1 Gy) doses of X-rays caused a delay in neurite outgrowth and a reduction in soma size, while only the high dose impaired neuronal survival. Of interest, the strongest effect on neuronal morphology and survival was evident in cells exposed to microgravity and in particular in cells exposed to both microgravity and radiation. Removal of neurons from simulated microgravity for a period of 24 h was not sufficient to recover neurite length, whereas the soma size showed a clear re-adaptation to normal ground conditions. Genome-wide gene expression analysis confirmed a modulation of genes involved in neurite extension, cell survival and synaptic communication, suggesting that these changes might be responsible for the observed morphological effects. In general, the observed synergistic changes in neuronal network integrity and cell survival induced by simulated space conditions might help to better evaluate the astronaut's health risks and underline the importance of investigating the central nervous system and long-term cognition during and after a space flight. PMID:27203085

  7. Impact of acute exposure to air pollution on the cardiorespiratory performance of military firemen.

    PubMed

    Oliveira, R S; Barros Neto, T L; Braga, A L F; Raso, V; Pereira, L A A; Morette, S R; Carneiro, R C

    2006-12-01

    The objective of the present study was to determine the impact of acute short-term exposure to air pollution on the cardiorespiratory performance of military firemen living and working in the city of Guarujá, São Paulo, Brazil. Twenty-five healthy non-smoking firemen aged 24 to 45 years had about 1 h of exposure to low and high levels of air pollution. The tests consisted of two phases: phase A, in Bertioga, a town with low levels of air pollution, and phase B, in Cubatão, a polluted town, with a 7-day interval between phases. The volunteers remained in the cities (Bertioga/Cubatão) only for the time required to perform the tests. Cumulative load 10 +/- 2 min-long exertion tests were performed on a treadmill, consisting of a 2-min stage at a load of 7 km/h, followed by increasing exertion of 1 km h-1 min-1 until the maximum individual limit. There were statistically significant differences (P < 0.05) in anaerobic threshold (AT) between Cubatão (35.04 +/- 4.91 mL kg-1 min-1) and Bertioga (36.98 +/- 5.62 mL kg-1 min-1; P = 0.01), in the heart rate at AT (AT HR; Cubatão 152.08 +/- 14.86 bpm, Bertioga 157.44 +/- 13.64 bpm; P = 0.001), and in percent maximal oxygen consumption at AT (AT%VO2max; Cubatão 64.56 +/- 6.55%, Bertioga 67.40 +/- 5.35%; P = 0.03). However, there were no differences in VO2max, maximal heart rate or velocity at AT (ATvel) observed in firemen between towns. The acute exposure to pollutants in Cubatão, SP, caused a significant reduction in the performance at submaximal levels of physical exertion.

  8. Anticholinergic drug exposure is associated with delirium and postdischarge institutionalization in acutely ill hospitalized older patients.

    PubMed

    Egberts, Angelique; van der Craats, Saskia T; van Wijk, Melissa D; Alkilabe, Shams; van den Bemt, Patricia M L A; Mattace-Raso, Francesco U S

    2017-06-01

    Several studies investigated the possible association between anticholinergic drugs and diverse clinical outcomes in older persons, but the results are inconsistent. The aim of this study was to investigate whether anticholinergic drug exposure is associated with delirium on admission, length of hospital stay, postdischarge institutionalization and in-hospital mortality in acutely ill hospitalized older patients. In this observational chart review study, we included acutely ill patients aged 65 and older who were admitted to the geriatric ward of the Erasmus University Medical Center, Rotterdam, The Netherlands, between 2012 and 2015 (n = 905). Anticholinergic drug exposure on admission was defined as the use of anticholinergic drugs, total number of anticholinergic drugs and anticholinergic drug burden score (ADB), quantified with the Anticholinergic Risk Scale (ARS), the Anticholinergic Cognitive Burden scale (ACB) and the list of Chew et al. (Chew). Logistic regression analyses were performed to investigate possible associations between anticholinergic drug exposure and the aforementioned outcomes. Analyses were adjusted for age, sex, comorbidities, non-anticholinergic drugs and delirium, where appropriate. Moderate and high ADB measured with the ARS were associated with delirium on admission with odds ratios (OR) of 1.70 (95% confidence interval (CI) = 1.16-2.49) and 1.83 (95% CI = 1.06-3.15), respectively. High ADB measured with the ARS was also associated with postdischarge institutionalization (OR = 2.43, 95% CI = 1.24-4.75). No associations were found using the ACB and Chew. Future studies are warranted to investigate the clinical usefulness of the ARS in reducing complications in older persons.

  9. Combined Exposure to Simulated Microgravity and Acute or Chronic Radiation Reduces Neuronal Network Integrity and Survival.

    PubMed

    Pani, Giuseppe; Verslegers, Mieke; Quintens, Roel; Samari, Nada; de Saint-Georges, Louis; van Oostveldt, Patrick; Baatout, Sarah; Benotmane, Mohammed Abderrafi

    2016-01-01

    During orbital or interplanetary space flights, astronauts are exposed to cosmic radiations and microgravity. However, most earth-based studies on the potential health risks of space conditions have investigated the effects of these two conditions separately. This study aimed at assessing the combined effect of radiation exposure and microgravity on neuronal morphology and survival in vitro. In particular, we investigated the effects of simulated microgravity after acute (X-rays) or during chronic (Californium-252) exposure to ionizing radiation using mouse mature neuron cultures. Acute exposure to low (0.1 Gy) doses of X-rays caused a delay in neurite outgrowth and a reduction in soma size, while only the high dose impaired neuronal survival. Of interest, the strongest effect on neuronal morphology and survival was evident in cells exposed to microgravity and in particular in cells exposed to both microgravity and radiation. Removal of neurons from simulated microgravity for a period of 24 h was not sufficient to recover neurite length, whereas the soma size showed a clear re-adaptation to normal ground conditions. Genome-wide gene expression analysis confirmed a modulation of genes involved in neurite extension, cell survival and synaptic communication, suggesting that these changes might be responsible for the observed morphological effects. In general, the observed synergistic changes in neuronal network integrity and cell survival induced by simulated space conditions might help to better evaluate the astronaut's health risks and underline the importance of investigating the central nervous system and long-term cognition during and after a space flight.

  10. Cumulative toxicity of neonicotinoid insecticide mixtures to Chironomus dilutus under acute exposure scenarios.

    PubMed

    Maloney, Erin M; Morrissey, Christy A; Headley, John V; Peru, Kerry M; Liber, Karsten

    2017-06-21

    Extensive agricultural use of neonicotinoid insecticide products has resulted in the presence of neonicotinoid mixtures in surface waters worldwide. Although many aquatic insect species are known to be sensitive to neonicotinoids, the impact of neonicotinoid mixtures is poorly understood. In the present study, the cumulative toxicities of binary and ternary mixtures of select neonicotinoids (imidacloprid, clothianidin, and thiamethoxam) were characterized under acute (96-h) exposure scenarios using the larval midge Chironomus dilutus as a representative aquatic insect species. Using the MIXTOX approach, predictive parametric models were fitted and statistically compared with observed toxicity in subsequent mixture tests. Single-compound toxicity tests yielded median lethal concentration (LC50) values of 4.63, 5.93, and 55.34 μg/L for imidacloprid, clothianidin, and thiamethoxam, respectively. Because of the similar modes of action of neonicotinoids, concentration-additive cumulative mixture toxicity was the predicted model. However, we found that imidacloprid-clothianidin mixtures demonstrated response-additive dose-level-dependent synergism, clothianidin-thiamethoxam mixtures demonstrated concentration-additive synergism, and imidacloprid-thiamethoxam mixtures demonstrated response-additive dose-ratio-dependent synergism, with toxicity shifting from antagonism to synergism as the relative concentration of thiamethoxam increased. Imidacloprid-clothianidin-thiamethoxam ternary mixtures demonstrated response-additive synergism. These results indicate that, under acute exposure scenarios, the toxicity of neonicotinoid mixtures to C. dilutus cannot be predicted using the common assumption of additive joint activity. Indeed, the overarching trend of synergistic deviation emphasizes the need for further research into the ecotoxicological effects of neonicotinoid insecticide mixtures in field settings, the development of better toxicity models for neonicotinoid mixture

  11. Assessments of lung toxicity to Acrawax C following acute inhalation exposure.

    PubMed

    Warheit, D B; Carakostas, M C; Hartsky, M A

    1990-01-01

    Acrawax is a trademark for a series of synthetic waxes which are used as flatteners in paint, and lubricants in plastics, and these materials have been routinely regarded as nuisance dusts. Due to a paucity of information regarding the pulmonary toxicity of this material, we investigated the effects of acute inhalation of Acrawax C in rats. CD rats were exposed to aerosols of Acrawax C for 6 hours at 112 mg/m3. Fluids and cells from sham and exposed animals were recovered by bronchoalveolar lavage (BAL) and measured for cellular and biochemical parameters at 0, 24, 48, 172 hrs (8 days), and 1 month postexposure. Pulmonary macrophages (PM) were cultured and studied for in vitro and in vivo phagocytosis, as well as surface morphology. The lungs of additional animals exposed to Acrawax were fixed for assessment by histopathology, and transmission electron microscopy. Our results showed that Acrawax C exposure produced a mild inflammatory response at 24 hours postexposure, but cell differentials were not significantly different from controls at 48 hrs after exposure. BAL levels of lactate dehydrogenase, alkaline phosphatase and protein were slightly different from controls only at 8 days postexposure, and had returned to control values by 1 month of recovery. Acrawax exposure had no adverse effects on either morphology or the phagocytic capacity of pulmonary macrophages recovered from exposed animals. Histopathologic analysis of lung tissue from Acrawax C-exposed rats revealed normal lung architecture. Based on acute studies, our results suggest that the response to inhaled Acrawax C is not substantially different from the response to other nuisance dusts such as carbonyl iron and titanium dioxide.

  12. Acute and recent air pollution exposure and cardiovascular events at labour and delivery

    PubMed Central

    Männistö, Tuija; Mendola, Pauline; Grantz, Katherine Laughon; Leishear, Kira; Sundaram, Rajeshwari; Sherman, Seth; Ying, Qi; Liu, Danping

    2017-01-01

    Objective To study the relationship between acute air pollution exposure and cardiovascular events during labour/delivery. Methods The Consortium on Safe Labor (2002–2008), an observational US cohort with 223 502 singleton deliveries provided electronic medical records. Air pollution exposure was estimated by modified Community Multiscale Air Quality models. Cardiovascular events (cardiac failure/arrest, stroke, myocardial infarcts and other events) were recorded in the hospital discharge records for 687 pregnancies (0.3%). Logistic regression with generalised estimating equations estimated the relationship between cardiovascular events and daily air pollutant levels for delivery day and the 7 days preceding delivery. Results Increased odds of cardiovascular events were observed for each IQR increase in exposure to nitric oxides at 5 and 6 days prior to delivery (OR=1.17, 99% CI 1.04 to 1.30 and OR=1.15, 1.03 to 1.28, respectively). High exposure to toxic air pollution species such as ethylbenzene (OR=1.50, 1.08 to 2.09), m-xylene (OR=1.54, 1.11 to 2.13), o-xylene (OR=1.51, 1.09 to 2.09), p-xylene (OR=1.43, 1.03 to 1.99) and toluene (OR=1.42, 1.02 to 1.97) at 5 days prior to delivery were also associated with cardiovascular events. Decreased odds of events were observed with exposure to ozone. Conclusions Air pollution in the days prior to delivery, especially nitrogen oxides and some toxic air pollution species, was associated with increased risk of cardiovascular events during the labour/delivery admission. PMID:26105036

  13. NEUROTOXICITY FOLLOWING ACUTE INHALATION EXPOSURE TO THE OIL DISPERSANT COREXIT EC9500A

    PubMed Central

    Sriram, Krishnan; Lin, Gary X.; Jefferson, Amy M.; Goldsmith, William T.; Jackson, Mark; McKinney, Walter; Frazer, David G.; Robinson, Victor A.; Castranova, Vincent

    2015-01-01

    Consequent to the 2010 Deepwater Horizon oil spill in the Gulf of Mexico, there is an emergent concern about the short- and long-term adverse health effects of exposure to crude oil, weathered-oil products, and oil dispersants among the workforce employed to contain and clean up the spill. Oil dispersants typically comprise of a mixture of solvents and surfactants that break down floating oil to micrometer-sized droplets within the water column, thus preventing it from reaching the shorelines. As dispersants are generally sprayed from the air, workers are at risk for exposure primarily via inhalation. Such inhaled fractions might potentially permeate or translocate to the brain via olfactory or systemic circulation, producing central nervous system (CNS) abnormalities. To determine whether oil dispersants pose a neurological risk, male Sprague-Dawley rats were exposed by whole-body inhalation exposure to a model oil dispersant, COREXIT EC9500A (CE; approximately 27 mg/m3 × 5 h/d × 1 d), and various molecular indices of neural dysfunction were evaluated in discrete brain areas, at 1 or 7 d postexposure. Exposure to CE produced partial loss of olfactory marker protein in the olfactory bulb. CE also reduced tyrosine hydroxylase protein content in the striatum. Further, CE altered the levels of various synaptic and neuronal intermediate filament proteins in specific brain areas. Reactive astrogliosis, as evidenced by increased expression of glial fibrillary acidic protein, was observed in the hippocampus and frontal cortex following exposure to CE. Collectively, these findings are suggestive of disruptions in olfactory signal transduction, axonal function, and synaptic vesicle fusion, events that potentially result in an imbalance in neurotransmitter signaling. Whether such acute molecular aberrations might persist and produce chronic neurological deficits remains to be ascertained. PMID:21916746

  14. Acute alcohol exposure during mouse gastrulation alters lipid metabolism in placental and heart development: Folate prevention

    PubMed Central

    Han, Mingda

    2016-01-01

    Background Embryonic acute exposure to ethanol (EtOH), lithium, and homocysteine (HCy) induces cardiac defects at the time of exposure; folic acid (FA) supplementation protects normal cardiogenesis (Han et al., 2009, 2012; Serrano et al., 2010). Our hypothesis is that EtOH exposure and FA protection relate to lipid and FA metabolism during mouse cardiogenesis and placentation. Methods On the morning of conception, pregnant C57BL/6J mice were placed on either of two FA‐containing diets: a 3.3 mg health maintenance diet or a high FA diet of 10.5 mg/kg. Mice were injected a binge level of EtOH, HCy, or saline on embryonic day (E) 6.75, targeting gastrulation. On E15.5, cardiac and umbilical blood flow were examined by ultrasound. Embryonic cardiac tissues were processed for gene expression of lipid and FA metabolism; the placenta and heart tissues for neutral lipid droplets, or for medium chain acyl‐dehydrogenase (MCAD) protein. Results EtOH exposure altered lipid‐related gene expression on E7.5 in comparison to control or FA‐supplemented groups and remained altered on E15.5 similarly to changes with HCy, signifying FA deficiency. In comparison to control tissues, the lipid‐related acyl CoA dehydrogenase medium length chain gene and its protein MCAD were altered with EtOH exposure, as were neutral lipid droplet localization in the heart and placenta. Conclusion EtOH altered gene expression associated with lipid and folate metabolism, as well as neutral lipids, in the E15.5 abnormally functioning heart and placenta. In comparison to controls, the high FA diet protected the embryo and placenta from these effects allowing normal development. Birth Defects Research (Part A) 106:749–760, 2016. © 2016 The Authors Birth Defects Research Part A: Clinical and Molecular Teratology Published by Wiley Periodicals, Inc. PMID:27296863

  15. Acute and recent air pollution exposure and cardiovascular events at labour and delivery.

    PubMed

    Männistö, Tuija; Mendola, Pauline; Laughon Grantz, Katherine; Leishear, Kira; Sundaram, Rajeshwari; Sherman, Seth; Ying, Qi; Liu, Danping

    2015-09-01

    To study the relationship between acute air pollution exposure and cardiovascular events during labour/delivery. The Consortium on Safe Labor (2002-2008), an observational US cohort with 223,502 singleton deliveries provided electronic medical records. Air pollution exposure was estimated by modified Community Multiscale Air Quality models. Cardiovascular events (cardiac failure/arrest, stroke, myocardial infarcts and other events) were recorded in the hospital discharge records for 687 pregnancies (0.3%). Logistic regression with generalised estimating equations estimated the relationship between cardiovascular events and daily air pollutant levels for delivery day and the 7 days preceding delivery. Increased odds of cardiovascular events were observed for each IQR increase in exposure to nitric oxides at 5 and 6 days prior to delivery (OR=1.17, 99% CI 1.04 to 1.30 and OR=1.15, 1.03 to 1.28, respectively). High exposure to toxic air pollution species such as ethylbenzene (OR=1.50, 1.08 to 2.09), m-xylene (OR=1.54, 1.11 to 2.13), o-xylene (OR=1.51, 1.09 to 2.09), p-xylene (OR=1.43, 1.03 to 1.99) and toluene (OR=1.42, 1.02 to 1.97) at 5 days prior to delivery were also associated with cardiovascular events. Decreased odds of events were observed with exposure to ozone. Air pollution in the days prior to delivery, especially nitrogen oxides and some toxic air pollution species, was associated with increased risk of cardiovascular events during the labour/delivery admission. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  16. Neurotoxicity following acute inhalation exposure to the oil dispersant COREXIT EC9500A.

    PubMed

    Sriram, Krishnan; Lin, Gary X; Jefferson, Amy M; Goldsmith, William T; Jackson, Mark; McKinney, Walter; Frazer, David G; Robinson, Victor A; Castranova, Vincent

    2011-01-01

    Consequent to the 2010 Deepwater Horizon oil spill in the Gulf of Mexico, there is an emergent concern about the short- and long-term adverse health effects of exposure to crude oil, weathered-oil products, and oil dispersants among the workforce employed to contain and clean up the spill. Oil dispersants typically comprise of a mixture of solvents and surfactants that break down floating oil to micrometer-sized droplets within the water column, thus preventing it from reaching the shorelines. As dispersants are generally sprayed from the air, workers are at risk for exposure primarily via inhalation. Such inhaled fractions might potentially permeate or translocate to the brain via olfactory or systemic circulation, producing central nervous system (CNS) abnormalities. To determine whether oil dispersants pose a neurological risk, male Sprague-Dawley rats were exposed by whole-body inhalation exposure to a model oil dispersant, COREXIT EC9500A (CE; approximately 27 mg/m(3) × 5 h/d × 1 d), and various molecular indices of neural dysfunction were evaluated in discrete brain areas, at 1 or 7 d postexposure. Exposure to CE produced partial loss of olfactory marker protein in the olfactory bulb. CE also reduced tyrosine hydroxylase protein content in the striatum. Further, CE altered the levels of various synaptic and neuronal intermediate filament proteins in specific brain areas. Reactive astrogliosis, as evidenced by increased expression of glial fibrillary acidic protein, was observed in the hippocampus and frontal cortex following exposure to CE. Collectively, these findings are suggestive of disruptions in olfactory signal transduction, axonal function, and synaptic vesicle fusion, events that potentially result in an imbalance in neurotransmitter signaling. Whether such acute molecular aberrations might persist and produce chronic neurological deficits remains to be ascertained.

  17. In Vitro Acute Exposure to DEHP Affects Oocyte Meiotic Maturation, Energy and Oxidative Stress Parameters in a Large Animal Model

    PubMed Central

    Sardanelli, Anna Maria; Pocar, Paola; Martino, Nicola Antonio; Paternoster, Maria Stefania; Amati, Francesca; Dell'Aquila, Maria Elena

    2011-01-01

    Phthalates are ubiquitous environmental contaminants because of their use in plastics and other common consumer products. Di-(2-ethylhexyl) phthalate (DEHP) is the most abundant phthalate and it impairs fertility by acting as an endocrine disruptor. The aim of the present study was to analyze the effects of in vitro acute exposure to DEHP on oocyte maturation, energy and oxidative status in the horse, a large animal model. Cumulus cell (CC) apoptosis and oxidative status were also investigated. Cumulus-oocyte complexes from the ovaries of slaughtered mares were cultured in vitro in presence of 0.12, 12 and 1200 µM DEHP. After in vitro maturation (IVM), CCs were removed and evaluated for apoptosis (cytological assessment and TUNEL) and intracellular reactive oxygen species (ROS) levels. Oocytes were evaluated for nuclear chromatin configuration. Matured (Metaphase II stage; MII) oocytes were further evaluated for cytoplasmic energy and oxidative parameters. DEHP significantly inhibited oocyte maturation when added at low doses (0.12 µM; P<0.05). This effect was related to increased CC apoptosis (P<0.001) and reduced ROS levels (P<0.0001). At higher doses (12 and 1200 µM), DEHP induced apoptosis (P<0.0001) and ROS increase (P<0.0001) in CCs without affecting oocyte maturation. In DEHP-exposed MII oocytes, mitochondrial distribution patterns, apparent energy status (MitoTracker fluorescence intensity), intracellular ROS localization and levels, mt/ROS colocalization and total SOD activity did not vary, whereas increased ATP content (P<0.05), possibly of glycolytic origin, was found. Co-treatment with N-Acetyl-Cysteine reversed apoptosis and efficiently scavenged excessive ROS in DEHP-treated CCs without enhancing oocyte maturation. In conclusion, acute in vitro exposure to DEHP inhibits equine oocyte maturation without altering ooplasmic energy and oxidative stress parameters in matured oocytes which retain the potential to be fertilized and develop into embryos

  18. (Acute radiation syndrome within the high-exposure group of Chernobyl)

    SciTech Connect

    Eckerman, K.F.

    1990-11-05

    Dr. K. F. Eckerman participated as a member of an American scientific team in meetings with Soviet scientists at the Institute of Biophysics in Moscow on October 18 and 19, 1990. The meetings were part of an agreement between the two countries under the Joint USSR-USA Coordinating Committee on Civil Nuclear Reactor Safety (JCCCNRS). The meetings were part of the efforts of Working Group 7.2 on Health Effects. These discussions were limited to the acute radiation syndrome (ARS) within the highly exposed Chernobyl patients. The specific objective of this meeting was to review the clinical and laboratory data on the Chernobyl ARS patients and to see what might be done to make these data available to improve our understanding of the syndrome.

  19. Immune status influences fear and anxiety responses in mice after acute stress exposure.

    PubMed

    Clark, Sarah M; Sand, Joseph; Francis, T Chase; Nagaraju, Anitha; Michael, Kerry C; Keegan, Achsah D; Kusnecov, Alexander; Gould, Todd D; Tonelli, Leonardo H

    2014-05-01

    Significant evidence suggests that exposure to traumatic and/or acute stress in both mice and humans results in compromised immune function that in turn may affect associated brain processes. Additionally, recent studies in mouse models of immune deficiency have suggested that adaptive immunity may play a role during traumatic stress exposure and that impairments in lymphocyte function may contribute to increased susceptibility to various psychogenic stressors. However, rodent studies on the relationship between maladaptive stress responses and lymphocyte deficiency have been complicated by the fact that genetic manipulations in these models may also result in changes in CNS function due to the expression of targeted genes in tissues other than lymphocytes, including the brain. To address these issues we utilized mice with a deletion of recombination-activating gene 2 (Rag2), which has no confirmed expression in the CNS; thus, its loss should result in the absence of mature lymphocytes without altering CNS function directly. Stress responsiveness of immune deficient Rag2(-/-) mice on a BALB/c background was evaluated in three different paradigms: predator odor exposure (POE), fear conditioning (FC) and learned helplessness (LH). These models are often used to study different aspects of stress responsiveness after the exposure to an acute stressor. In addition, immunoblot analysis was used to assess hippocampal BDNF expression under both stressed and non-stressed conditions. Subsequent to POE, Rag2(-/-) mice exhibited a reduced acoustic startle response compared to BALB/c mice; no significant differences in behavior were observed in either FC or LH. Furthermore, analysis of hippocampal BDNF indicated that Rag2(-/-) mice have elevated levels of the mature form of BDNF compared to BALB/c mice. Results from our studies suggest that the absence of mature lymphocytes is associated with increased resilience to stress exposure in the POE and does not affect behavioral

  20. Comparison of the responses of children and adults to acute ozone exposure

    SciTech Connect

    McDonnell, W.F.; Chapman, R.S.; Horstman, D.H.; Leigh, M.W.; Salaam, S.A.

    1986-07-01

    The purpose of the paper is to compare the results of two studies in which the respiratory responses of children and adults to acute ozone (O/sub 3/) exposure were measured. Forty-two 18-30 year old males were exposed for 2.5 hours in a controlled environmental chamber to either 0.0 or 0.12 ppm O3 while performing intermittent heavy exercise. Twenty-two 8-11 year old males were exposed in a similar manner to both air and 0.12 ppm O3. Measures of respiratory symptoms and function were made before and after exposure. Adults experienced an increase in the symptom cough and decrements in forced vital capacity and some measures of forced expiratory flow. Children experienced similar decrements in pulmonary function, but had no increase in symptoms. The authors concluded that as measured by pulmonary function children appear to be no more responsive to O3 exposure than are adults and may experience fewer symptoms.

  1. Oxidative Status and Acute Phase Reactants in Patients with Environmental Asbestos Exposure and Mesothelioma

    PubMed Central

    Sezgi, Cengizhan; Taylan, Mahsuk; Selimoglu Sen, Hadice; Evliyaoğlu, Osman; Kaya, Halide; Abakay, Ozlem; Abakay, Abdurrahman; Tanrıkulu, Abdullah Cetin; Senyiğit, Abdurrahman

    2014-01-01

    Background and Objectives. The aim of this study was to investigate inflammatory indicators and oxidative status in patients with asbestos exposure with and without mesothelioma and to compare results with data from healthy subjects. Methods. Eighty people with exposure to environmental asbestos and without any disease, 46 mesothelioma patients, and a control group of 50 people without exposure to environmental asbestos were enrolled in this prospective study. Serum total oxidant level (TOL), total antioxidant capacity (TAC), and oxidative stress index (OSI), CRP, transferrin, ceruloplasmin, α-1 antitrypsin, ferritin, and copper levels were measured. Results. Mesothelioma group exhibited higher TOL, OSI, α1-antitrypsin, ferritin and copper levels as compared to the other groups (P < 0.001, P = 0.007, P < 0.0001, P < 0.001, and P < 0.001, resp.). Transferrin was lower in the mesothelioma group than in the other two groups (P < 0.001). The asbestos group had higher TOL, TAC, α1-antitrypsin, and transferrin levels (P < 0.001, P < 0.001, P < 0.001, and P < 0.001, resp.), as well as lower OSI and ferritin levels as compared to the control group (P < 0.001 and P < 0.001). Conclusions. We believe that elevated acute phase reactants and oxidative stress markers (TOL and OSI) in the mesothelioma group can be used as predictive markers for the development of asbestos-related malignancy. PMID:24592197

  2. Acute effects of chlorinated resin acid exposure on juvenile rainbow trout, Oncorhynchus mykiss

    SciTech Connect

    Kennedy, C.J.; Sweeting, R.M.; Farrell, A.P.; McKeown, B.A.; Johansen, J.A.

    1995-06-01

    The effects of an acute exposure to either 14-monochlorodehydroabietic acid (MCDHAA) or 12,14-dichlorodehydroabietic acid (DCDHAA) were examined in juvenile rainbow trout, Oncorhynchus mykiss. The experimentally determined 96-h LC50 values (and their 95% confidence limits) were 1.03 (0.72, 1.48) and 0.91 (0.70, 1.21) mg/L, for MCDHAA and DCDHAA, respectively. To measure effects on several biochemical parameters, swimming performance, and disease resistance, juvenile trout were exposed for 24 h to sublethal concentrations of one or the other resin acid in an intermittent-flow respirometer. Hematocrit, plasma lactate, and liver protein were significantly affected by exposure to the highest dose (80% of the 96-h LC50 value) of either of the resin acids. Plasma cortisol levels were 14- and 3-fold higher than were controls. Resistance to infection by Aeromonas salmonicida was significantly reduced; the cumulative percent mortalities due to furunculosis in fish exposed to MCDHAA or DCDHAA reached 20 and 26%, respectively. Swimming performance, measured as critical swimming speed (mean values 6.32 {+-} 0.20 and 5.93 {+-} 0.15 body lengths per second for MCDHAA and DCDHAA, respectively), was not significantly affected by resin acid exposure.

  3. Acute nose-only inhalation exposure of rats to di- and triphosgene relative to phosgene.

    PubMed

    Pauluhn, Jürgen

    2011-02-01

    Groups of young adult Wistar rats were acutely exposed to trichloromethyl chloroformate (diphosgene) and bis(trichloromethyl) carbonate (triphosgene) vapor atmospheres using a directed-flow nose-only mode of exposure. The exposure duration used was 240 min. The median lethal concentration (LC50) of diphosgene and triphosgene was 13.9 and 41.5 mg/m3, respectively. Based on the molar exposure concentrations, the LC50s of phosgene (previously published), diphosgene, and triphosgene were 0.07, 0.07, and 0.14 mmol/m3, respectively. Although the principal toxic mode of action of the volatile diphosgene was similar to phosgene gas, the vapor phase of triphosgene appeared to be different to that of phosgene and diphosgene based on a more persistent occurrence of signs of respiratory distress and a biphasic onset of mortality. While all substances caused mortality within 1 day postexposure, triphosgene induced a second phase of mortality 11?14 days postexposure. The vapor saturation concentration of triphosgene at ambient temperature is ?100 times its LC50. In summary, triphosgene-induced lung injury patterns are different from that of phosgene and diphosgene. More research is needed to close the substantial data gaps of triphosgene.

  4. Setting safe acute exposure limits for halon replacement chemicals using physiologically based pharmacokinetic modeling.

    PubMed

    Vinegar, A; Jepson, G W; Cisneros, M; Rubenstein, R; Brock, W J

    2000-08-01

    Most proposed replacements for Halon 1301 as a fire suppressant are halogenated hydrocarbons. The acute toxic endpoint of concern for these agents is cardiac sensitization. An approach is described that links the cardiac endpoint as assessed in dogs to a target arterial concentration in humans. Linkage was made using a physiologically based pharmacokinetic (PBPK) model. Monte Carlo simulations, which account for population variability, were used to establish safe exposure times at different exposure concentrations for Halon 1301 (bromotrifluoromethane), CF(3)I (trifluoroiodomethane), HFC-125 (pentafluoroethane), HFC-227ea (1,1,1,2,3,3,3-heptafluoropropane), and HFC-236fa (1,1,1,3,3,3-hexafluoropropane). Application of the modeling technique described here not only makes use of the conservative cardiac sensitization endpoint, but also uses an understanding of the pharmacokinetics of the chemical agents to better establish standards for safe exposure. The combined application of cardiac sensitization data and physiologically based modeling provides a quantitative approach, which can facilitate the selection and effective use of halon replacement candidates.

  5. Exposure data for the study of acute health effects of air pollution.

    PubMed

    Goldstein, I F

    1979-01-01

    The use of aerometric network data has been criticized before on the grounds that it might give an unreliable picture of population exposure. However, the extensive data obtained from networks is still being used for studies of health effects of air pollution. This study uses a rigorous approach in analyzing these data to test their suitability for studies of acute health effects of air pollution. New York City, with one of the most extensive aerometric networks, consisting of 40 air pollution monitoring stations, is taken as an example. Three years of hourly SO2 readings and bi-hourly readings of smokeshade have been analyzed. The use of one aerometric station to represent the daily exposure of the population of New York City as has been done in previous studies is shown to be invalid. The use of individual monitoring stations of the New York City aerometric network to represent the day-to-day exposure to SO2 and smokeshade of the populations surrounding these monitoring stations is examined, with results showing that further work will be necessary before such an approach is justified.

  6. Differential disruption of nuclear volume and neuronal phenotype in the preoptic area by neonatal exposure to genistein and bisphenol-A.

    PubMed

    Patisaul, Heather B; Fortino, Anne E; Polston, Eva K

    2007-01-01

    Changes in the volumes of sexually dimorphic brain nuclei are often used as a biomarker for developmental disruption by endocrine-active compounds (EACs). However, these gross, morphological analyses do not reliably predict disruption of cell phenotype or neuronal function. In the present experiments, we used a more comprehensive approach to assess whether postnatal exposure to the EACs genistein (GEN) or bisphenol-A (BIS) affected the development of two sexually dimorphic brain regions in male rats: the anteroventral periventricular nucleus of the hypothalamus (AVPV) and the sexually dimorphic nucleus of the preoptic area (SDN). In addition to nuclear volumes, we also measured the number of immunopositive calbindin neurons in the SDN and the activational patterns of gonadotropin-releasing hormone (GnRH) neurons, a neuronal population that is functionally linked to the AVPV. In rats, exposure of the neonatal male brain to endogenous estrogen, aromatized from testicular testosterone, is essential for the proper sexual differentiation of these endpoints. Thus, we hypothesized that exposure to BIS and GEN during this critical period could disrupt brain sexual differentiation. Animals were given four subcutaneous injections of sesame oil (control), 250 microg GEN, or 250 microg BIS at 12 h intervals over postnatal days (PND) 1 and 2, gonadectomized on PND 85, and treated sequentially with estrogen and progesterone to stimulate Fos expression in GnRH neurons, a marker for their activation. A cohort of age-matched ovariectomized (OVX) females that were given the same hormone treatment in adulthood served as a positive control group. SDN volume was unchanged by treatment, but the number of calbindin neurons in the SDN was significantly increased by both BIS and GEN. GEN, but not BIS, demasculinized male AVPV volume, but patterns of GnRH neuronal activation were not affected by either compound. These results suggest that acute exposure to EACs during a critical

  7. ACUTE NEUROTOXIC EFFECTS OF INHALED PERCHLOROETHYLENE ON PATTERN VISUAL EVOKED POTENTIALS AS A FUNCTION OF EXPOSURE AND ESTIMATED BLOOD AND BRAIN CONCENTRATION.

    EPA Science Inventory

    Previous experiments have shown the effects of acute inhalation exposure to trichloroethylene (TCE) and toluene are related to the target tissue concentration at the time of testing. The current studies examined exposure to another volatile organic compound, perchloroethylene (P...

  8. ACUTE NEUROTOXIC EFFECTS OF INHALED PERCHLOROETHYLENE ON PATTERN VISUAL EVOKED POTENTIALS AS A FUNCTION OF EXPOSURE AND ESTIMATED BLOOD AND BRAIN CONCENTRATION.

    EPA Science Inventory

    Previous experiments have shown the effects of acute inhalation exposure to trichloroethylene (TCE) and toluene are related to the target tissue concentration at the time of testing. The current studies examined exposure to another volatile organic compound, perchloroethylene (P...

  9. Monitoring the critical radiation exposure pathways at a BWR nuclear power station.

    PubMed

    Golden, J C; Chandrasekaran, E S; Kahn, B

    1982-06-01

    Iodine-131 in milk and gamma radiation from radionuclides in air in the environment of a 3-unit nuclear power station were measured at the levels predicted for airborne effluent. These measurements were part of a modified environmental radiological monitoring program to confirm the population doses computed from radionuclide release rates and environmental transfer models. The limits of detection were lowered relative to conventional monitoring programs by analyzing 21 L samples of milk for 131I and by determining external gamma radiation with a system that combined use of thermoluminescent dosimeters, pressurized ionization chambers, and NaI(T1) survey meters. For monitoring periods slightly longer than 6 months, during a time when fallout from atmospheric nuclear tests contributed very little, the average measured 131I concentration in milk was 0.1 pCi/L for cows on a nearby pasture and 0.02 pCi/L for cows at a more distant control location, compared to predicted values of 0.07 and 0.02 pCi/L, respectively; the average radiation exposure from airborne radionuclides measured at 16 nearby dosimeter locations was 7 mR, compared to the average of predicted values of 4 mR.

  10. Acute β-Adrenergic Activation Triggers Nuclear Import of Histone Deacetylase 5 and Delays Gq-induced Transcriptional Activation*

    PubMed Central

    Chang, Chia-Wei Jenny; Lee, Linda; Yu, David; Dao, Khanha; Bossuyt, Julie; Bers, Donald M.

    2013-01-01

    During hemodynamic stress, catecholamines and neurohumoral stimuli may induce co-activation of Gq-coupled receptors and β-adrenergic receptors (β-AR), leading to cardiac remodeling. Dynamic regulation of histone deacetylase 5 (HDAC5), a transcriptional repressor, is crucial during stress signaling due to its role in epigenetic control of fetal gene markers. Little is known about its regulation during acute and chronic β-AR stimulation and its cross-interaction with Gq signaling in adult cardiac myocytes. Here, we evaluate the potential cross-talk between Gq-driven and β-AR mediated signaling at the level of nucleocytoplasmic shuttling of HDAC5. We show the translocation of GFP-tagged wild type HDAC5 or mutants (S279A and S279D) in response to β-AR or Gq agonists. Isoproterenol (ISO) or PKA activation results in strong nuclear accumulation of HDAC5 in contrast to nuclear export driven by Ca2+-calmodulin protein kinase II and protein kinase D. Moreover, nuclear accumulation of HDAC5 under acute ISO/PKA signaling is dependent on phosphorylation of Ser-279 and can block subsequent Gq-mediated nuclear HDAC5 export. Intriguingly, the attenuation of Gq-induced export is abolished after chronic PKA activation, yet nuclear HDAC5 remains elevated. Last, the effect of chronic β-AR signaling on HDAC5 translocation was examined in adult myocytes from a rabbit model of heart failure, where ISO-induced nuclear import is ablated, but Gq-agonist mediated export is preserved. Acute β-AR/PKA activation protects against hypertrophic signaling by delaying Gq-mediated transcriptional activation. This serves as a key physiological control switch before allowing genetic reprogramming via HDAC5 nuclear export during more severe stress, such as heart failure. PMID:23161540

  11. Health concerns related to radiation exposure of the female nuclear medicine patient.

    PubMed Central

    Stabin, M G

    1997-01-01

    The female nuclear medicine patient is of special concern in evaluating radiation dose and risk in nuclear medicine. The female's overall body size and organ sizes generally are smaller than those of her male counterpart (thus her radiation doses will be higher, given the same amounts of administered activity and similar biokinetics); female gonads are inside the body instead of outside and are near several organs often important as source organs in internal dosimetry (urinary bladder, liver, kidneys, intestines); risk of breast cancer is significantly higher among females than males; and in the case of pregnancy, exposure to radiation of the embryo/fetus and the nursing infant are of special concern in such an analysis. All these concerns are addressed in this study through a comparative study of radiation doses for males and females over a large number (approximately 60) of nuclear medicine studies and through a study of what is known about radiation dosimetry in pregnancy and breast feeding. It was found that women's critical organ doses and effective doses (as defined by the International Commission on Radiological Protection 60 [ICRP 60] are about 25% higher than those for men across all these studies. Women's gonad doses, however, may be as much as 10 to 30 times higher than those in men, although 2- to 3-fold differences are common. Many radiopharmaceuticals are administered to women of childbearing age; however, little is known about how much activity crosses the placenta and about the biokinetics in the fetus should it occur. Nonetheless, dose estimates are provided at four stages of pregnancy (early, 3-month, 6-month, and 9-month gestation) for a large number of radiopharmaceuticals, whether or not quantitative estimates of placental crossover can be made. Many radiopharmaceuticals are also excreted in breast milk of nursing mothers. Breast feeding interruption schedules are suggested through analysis of the observed kinetics of these pharmaceuticals and

  12. ACUTE CHANGES IN PASSIVE GLENOHUMERAL ROTATION FOLLOWING TENNIS PLAY EXPOSURE IN ELITE FEMALE PLAYERS

    PubMed Central

    Kibler, W. Ben; Myers, Natalie L.; Smith, Belinda J.

    2016-01-01

    Background Alterations in glenohumeral (GH) rotation especially internal rotation and total range of motion have been associated with altered GH kinematics and susceptibility to injury. Researchers have evaluated long-term change in baseball and tennis players, and short-term changes in baseball players. However, acute (short-term) changes in GH rotation have not been evaluated in tennis players. Hypotheses/Purpose The purpose of this study was to quantify short-term glenohumeral rotational changes within a group of professional women's tennis players following competitive play. It was hypothesized that there would be acute alterations in passive glenohumeral internal rotation and total range of motion following episodes of tennis play. Study Design Cohort Study Methods Passive glenohumeral external rotation (GER), glenohumeral internal rotation (GIR), and total range of motion (TROM) were evaluated in a cohort of 79 professional adult female tennis players. Measurements were taken at three different time points (TP): baseline before match play (TP1), immediately after match play (TP2), and 24-hours after baseline (TP3). Results There was a statistically significant decrease in the mean GIR from TP1 (43 ± 11 °) to TP2 (39 ± 9 °) (p=0.002) and from TP1 to TP3 (38 ± 10 °) (p=0.001). All measures were at the level of minimal detectable change (MDC) (4 °) indicating clinical significance. There was a decrease in mean TROM from TP1 (146 ± 11 °) to TP2 (142 ± 12 °) (p=0.04), which was not above MDC (7 °). Subgroup analysis showed that 47% of the players demonstrated a decrease in GIR beyond MDC, and 37% demonstrated a decrease in TROM beyond MDC. GER remained unchanged across all time points (p>0.05). Conclusion Both GIR and TROM were reduced after acute exposure to tennis play. In a large subgroup of the cohort, the changes were clinically significant and approached values previously demonstrated to be associated with

  13. ANALYSIS OF EARTHWORM SUB-LETHAL TOXIC RESPONSES TO ATRAZINE EXPOSURE USING (1) H NUCLEAR MAGNETIC RESONANCE (NMR)-BASED METABOLOMICS.

    PubMed

    Dani, Vivek D; Simpson, André J; Simpson, Myrna J

    2017-09-09

    Atrazine toxicity to earthworms is still not fully understood, particularly at sub-lethal concentrations. Because of the ubiquity of atrazine in the environment, it is imperative to understand the impacts of atrazine presence on soil-dwelling organisms. To examine this in detail, we used (1) H nuclear magnetic resonance (NMR)-based metabolomics to elucidate earthworm (Eisenia fetida) responses after a 48 h of atrazine exposure in contact tests. Earthworms were exposed to four sub-lethal concentrations of 362.4 ng/cm(2) , 181.2 ng/cm(2) , 90.6 ng/cm(2) and 45.3 ng/cm(2) , which correspond to 1/8(th) , 1/16(th) , 1/32(nd) and 1/64(th) of the LC50 value respectively. After exposure, polar metabolites were isolated from earthworm tissues and analyzed using (1) H NMR spectroscopy. Sub-lethal atrazine exposure induced a non-monotonic response with respect to exposure concentration and caused an overall suppression in earthworm metabolism. Maltose, fumarate, malate, threonine/lactate, adenosine-5'-triphosphate (ATP), betaine, scyllo-inositol, glutamate, arginine and glutamine were the metabolites identified as most sensitive to atrazine exposure. These observed fluctuations in the metabolic profile suggest that atrazine reduced ATP synthesis and negatively impacted the health of earthworms with acute sub-lethal exposure. Our study also demonstrates the utility of NMR-based metabolomics for the basic assessment of sub-lethal toxicity which can then be used for more targeted approaches with other molecular techniques. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  14. The body weight loss during acute exposure to high-altitude hypoxia in sea level residents.

    PubMed

    Ge, Ri-Li; Wood, Helen; Yang, Hui-Huang; Liu, Yi-Ning; Wang, Xiu-Juan; Babb, Tony

    2010-12-25

    Weight loss is frequently observed after acute exposure to high altitude. However, the magnitude and rate of weight loss during acute exposure to high altitude has not been clarified in a controlled prospective study. The present study was performed to evaluate weight loss at high altitude. A group of 120 male subjects [aged (32±6) years] who worked on the construction of the Golmud-Lhasa Railway at Kunlun Mountain (altitude of 4 678 m) served as volunteer subjects for this study. Eighty-five workers normally resided at sea level (sea level group) and 35 normally resided at an altitude of 2 200 m (moderate altitude group). Body weight, body mass index (BMI), and waist circumference were measured in all subjects after a 7-day stay at Golmud (altitude of 2 800 m, baseline measurements). Measurements were repeated after 33-day working on Kunlun Mountain. In order to examine the daily rate of weight loss at high altitude, body weight was measured in 20 subjects from the sea level group (sea level subset group) each morning before breakfast for 33 d at Kunlun Mountain. According to guidelines established by the Lake Louise acute mountain sickness (AMS) consensus report, each subject completed an AMS self-report questionnaire two days after arriving at Kunlun Mountain. After 33-day stay at an altitude of 4 678 m, the average weight loss for the sea level group was 10.4% (range 6.5% to 29%), while the average for the moderate altitude group was 2.2% (-2% to 9.1%). The degree of weight loss (Δ weight loss) after a 33-day stay at an altitude of 4 678 m was significantly correlated with baseline body weight in the sea level group (r=0.677, P<0.01), while the correlation was absent in the moderate altitude group (r=0.296, P>0.05). In the sea level subset group, a significant weight loss was observed within 20 d, but the weight remained stable thereafter. AMS-score at high altitude was significantly higher in the sea level group (4.69±2.48) than that in the moderate

  15. The effects of acute cold exposure on morphology and gene expression in the heart of neonatal chicks.

    PubMed

    Matsubara, Tomoko; Shimamoto, Saki; Ijiri, Daichi; Ohtsuka, Akira; Kanai, Yukio; Hirabayashi, Miho

    2016-04-01

    Cold exposure induces an increase in blood flow and blood pressure, and long-term exposure to cold causes cardiac hypertrophy. Neonatal chicks (Gallus gallus domesticus) are highly sensitive to cold exposure, because their capacity for thermogenesis is immature until 1 week after hatching. Hence, we hypothesized that the heart of chicks at around 1 week of age acutely responds to cold environment. To investigate the effect of acute (24 h) and long-term (2 weeks) cold on the heart of chicks, 7-day-old chicks were exposed to cold temperature (4 °C) or kept warm (30 °C). Chicks exposed to the cold showed cardiac hypertrophy with marked left ventricular (LV) chamber dilation and wall thickening. On the other hand, long-term cold exposure (2 weeks from 7-day-old) induced an increase in total ventricular mass, but not in LV morphological parameters. Then, we investigated the details of acute cardiac hypertrophy in chicks. Electron microscopy revealed that cardiomyocytes in the hypertrophied LV had enlarged mitochondria with less dense cristae. Although the mRNA expression of lipoprotein lipase in the LV of the cold-exposed chicks significantly increased, the mRNA expression of genes involved in fatty acid β-oxidation did not change in response to cold exposure. In addition, the mRNA expression of peroxisome proliferator-activated receptor gamma coactivator-1 alpha, which enhances mitochondrial biogenesis and function under physiological cardiac hypertrophy, increased in LV of cold-exposed chicks. The study found that acute cold exposure to neonatal chicks induces LV hypertrophy. However, these results suggest that acute cold exposure to chicks might induce both adaptive and maladaptive responses of the LV.

  16. Effects of Nuclear Cross Sections at Different Energies on Space Radiation Exposure from Galactic Cosmic Rays

    NASA Technical Reports Server (NTRS)

    Li, Zi-Wei; Adams, James H., Jr.

    2007-01-01

    Space radiation from galactic cosmic rays (GCR) is a major hazard to space crews, especially in long duration human space explorations. For this reason, they will be protected by radiation shielding that fragments the GCR heavy ions. Here we investigate how sensitive the crew's radiation exposure is to nuclear fragmentation cross sections at different energies. We find that in deep space cross sections between about 0.2 and 1.2 GeV/u have the strongest effect on dose equivalent behind shielding in solar minimum GCR environments, and cross sections between about 0.6 and 1.7 GeV/u are the most important at solar maximum'. On the other hand, at the location of the International Space Station, cross sections at_higher -energies, between about 0.6 and 1.7 GeV /u at solar minimum and between about 1.7 and 3.4 GeV/u'at,solar maximum, are the most important This is. due-to the average geomagnetic cutoff for the ISS orbit. We also show the effect of uncertainties in the fragmentation cross sections on the elemental energy spectra behind shielding. These results help to focus the studies of fragmentation cross sections on the proper energy range in order to improve our predictions of crew exposures.

  17. Effects of Nuclear Cross Sections at Different Energies on Space Radiation Exposure from Galactic Cosmic Rays

    NASA Technical Reports Server (NTRS)

    Li, Zi-Wei; Adams, James H., Jr.

    2007-01-01

    Space radiation from galactic cosmic rays (GCR) is a major hazard to space crews, especially in long duration human space explorations. For this reason, they will be protected by radiation shielding that fragments the GCR heavy ions. Here we investigate how sensitive the crew's radiation exposure is to nuclear fragmentation cross sections at different energies. We find that in deep space cross sections between about 0.2 and 1.2 GeV/u have the strongest effect on dose equivalent behind shielding in solar minimum GCR environments, and cross sections between about 0.6 and 1.7 GeV/u are the most important at solar maximum'. On the other hand, at the location of the International Space Station, cross sections at_higher -energies, between about 0.6 and 1.7 GeV /u at solar minimum and between about 1.7 and 3.4 GeV/u'at,solar maximum, are the most important This is. due-to the average geomagnetic cutoff for the ISS orbit. We also show the effect of uncertainties in the fragmentation cross sections on the elemental energy spectra behind shielding. These results help to focus the studies of fragmentation cross sections on the proper energy range in order to improve our predictions of crew exposures.

  18. Acute Acrolein Exposure Induces Impairment of Vocal Fold Epithelial Barrier Function

    PubMed Central

    Zheng, Wei; Sivasankar, M. Preeti

    2016-01-01

    Acrolein is a ubiquitous pollutant abundant in cigarette smoke, mobile exhaust, and industrial waste. There is limited literature on the effects of acrolein on vocal fold tissue, although there are clinical reports of voice changes after pollutant exposures. Vocal folds are responsible for voice production. The overall objective of this study was to investigate the effects of acrolein exposure on viable, excised vocal fold epithelial tissue and to characterize the mechanism underlying acrolein toxicity. Vocal fold epithelia were studied because they form the outermost layer of the vocal folds and are a primary recipient of inhaled pollutants. Porcine vocal fold epithelia were exposed to 0, 50, 100, 500, 900 or 1300 μM of acrolein for 3 hours; the metabolic activity, epithelial resistance, epithelial permeability, tight junction protein (occludin and claudin 3) expression, cell membrane integrity and lipid peroxidation were investigated. The data demonstrated that acrolein exposure at 500 μM significantly reduced vocal fold epithelial metabolic activity by 27.2% (p≤0.001). Incubation with 100 μM acrolein caused a marked increase in epithelial permeability by 130.5% (p<0.05) and a reduction in transepithelial electrical resistance (TEER) by 180.0% (p<0.001). While the expression of tight junctional protein did not change in acrolein-treated samples, the cell membrane integrity was significantly damaged with a 45.6% increase of lipid peroxidation as compared to controls (p<0.05). Taken together, these data provide evidence that acute acrolein exposure impairs vocal fold epithelial barrier integrity. Lipid peroxidation-induced cell membrane damage may play an important role in reducing the barrier function of the epithelium. PMID:27643990

  19. 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.

  20. Association between ambient noise exposure, hearing acuity, and risk of acute occupational injury

    PubMed Central

    Cantley, Linda F; Galusha, Deron; Cullen, Mark R; Dixon-Ernst, Christine; Rabinowitz, Peter M; Neitzel, Richard L

    2015-01-01

    Objective This study aimed to examine the associations between acute workplace injury risk, ambient noise exposure, and hearing acuity, adjusting for reported hearing protection use. Methods In a cohort of 9220 aluminum manufacturing workers studied over six years (33 300 person-years, 13 323 person-jobs), multivariate mixed effects models were used to estimate relative risk (RR) of all injuries as well as serious injuries by noise exposure category and hearing threshold level (HTL) adjusting for recognized and potential confounders. Results Compared to noise <82 dBA, higher exposure was associated with elevated risk in a monotonic and statistically significant exposure–response pattern for all injuries and serious injuries with higher risk estimates observed for serious injuries [82–84.99 dBA: RR 1.26, 95% confidence interval (95% CI) 0.96–1.64; 85–87.99 dBA: RR 1.39, 95% CI 1.05–1.85; ≥88 dBA: RR 2.29, 95% CI 1.52–3.47]. Hearing loss was associated with increased risk for all injuries, but was not a significant predictor of risk for the subset of more serious injuries. Compared to those without hearing loss, workers with HTL ≥25 dB had 21% increased all injury risk (RR 1.21, 95% CI 1.09–1.33) while those with HTL 10–24.99 dB had 6% increased risk (RR 1.06, 95% CI 1.00–1.13). Reported hearing protection type did not predict injury risk. Conclusion Noise exposure levels as low as 85 dBA may increase workplace injury risk. HTL was associated with increased risk for all, but not the subset of serious, injuries. Additional study is needed both to confirm the observed associations and explore causal pathways. PMID:25137556

  1. Tobacco Smoke Exposure and the Risk of Childhood Acute Lymphoblastic and Myeloid Leukemias by Cytogenetic Subtype

    PubMed Central

    Metayer, Catherine; Zhang, Luoping; Wiemels, Joseph L.; Bartley, Karen; Schiffman, Joshua; Ma, Xiaomei; Aldrich, Melinda C.; Chang, Jeffrey S.; Selvin, Steve; Fu, Cecilia H.; Ducore, Jonathan; Smith, Martyn T.; Buffler, Patricia A.

    2013-01-01

    Background Tobacco smoke contains carcinogens known to damage somatic and germ cells. We investigated the effect tobacco smoke on the risk of childhood acute lymphoblastic leukemia (ALL) and myeloid leukemia (AML), especially subtypes of pre-natal origin like ALL with translocation t(12;21) or high-hyperdiploidy (51–67 chromosomes). Methods We collected information on exposures to tobacco smoking before conception, during pregnancy, and after birth in 767 ALL cases, 135 AML cases, and 1,139 controls (1996–2008). Among cases, chromosome translocations, deletions, or aneuploidy were identified by conventional karyotype and fluorescence in-situ hybridization. Results Multivariable regression analyses for ALL and AML overall showed no definite evidence of associations with self-reported (yes/no) parental prenatal active smoking and child's passive smoking. However, children with history of paternal prenatal smoking combined with postnatal passive smoking had a 1.5-fold increased risk of ALL (95% CI: 1.01–2.23), compared to those without smoking history (ORs for pre- or postnatal smoking only were close to one). This joint effect was seen for B-cell precursor ALL with t(12;21) (OR=2.08; 95% CI: 1.04–4.16), but not high hyperdiploid B-cell ALL. Similarly, child's passive smoking was associated with an elevated risk of AML with chromosome structural changes (OR=2.76; 95% CI: 1.01–7.58), but not aneuploidy. Conclusions our data suggest that exposure to tobacco smoking before were associated with increased risks of childhood ALL and AML; and risks varied by timing of exposure (before and/or after birth) and cytogenetic subtype, based on imprecise estimates. Impact Parents should limit exposures to tobacco smoke before and after the child's birth. PMID:23853208

  2. Nicotine effects on thermoregulatory responses of men and women during acute cold exposure.

    PubMed

    Cheatham, Christopher C; Caine-Bish, Natalie; Blegen, Mark; Potkanowicz, Edward S; Glickman, Ellen L

    2004-07-01

    Due to the impact of nicotine (NIC) on the physiological processes involved in temperature regulation during cold exposure, it is conceivable that NIC may affect the body's thermoregulatory abilities during a cold stress. Thus, the purpose of this study was to examine the effects of NIC on thermoregulatory responses during acute cold exposure. There were six men and six women between the ages of 18 and 25 yr who participated in this study. All subjects were active, apparently healthy smokers. Each subject performed two cold air trials consisting of a 30-min baseline period (BASE) and a 120-min exposure to 10 degrees C air. One cold air trial was performed following a NIC dosing using a 21-mg transdermal patch while the other trial was performed after a placebo (PL) treatment. During the cold air trials, there were no differences in rectal temperature (Tre) or mean skin temperature (Tsk) between the PL and NIC treatments in either sex (p > 0.05). However, in men, heat production (M) was 12% lower (p < or = 0.05) and tissue insulation was 17% higher (p < or = 0.05) during the NIC treatment compared with the PL treatment, while these responses in women were unaffected. In both men and women, finger skin vascular conductance (SVCfin), expressed as a percentage of the BASE value, was higher during the NIC treatment compared with the PL treatment during the cold air trials (p < or = 0.05). Lastly, throughout the cold air trials, there was no difference in thermal sensation between the PL and NIC treatments (p > 0.05). In conclusion, although NIC administration resulted in sex-specific alterations in M and tissue insulation during cold exposure, the response in Tre was unaffected.

  3. Activation of NRF2 pathway in spleen, thymus as well as peripheral blood mononuclear cells by acute arsenic exposure in mice.

    PubMed

    Duan, Xiaoxu; Li, Jinlong; Zhang, Yang; Li, Wei; Zhao, Lu; Nie, Huifang; Sun, Guifan; Li, Bing

    2015-10-01

    Arsenic has already been demonstrated to activate the nuclear factor erythroid 2-related factor 2 (NRF2) in many different organs and cell lines. The present study tried to explore the expression of NRF2 pathway by acute arsenic exposure in immune system in vivo. Our results showed that treatment with arsenic (sodium arsenite, 5, 10 and 20mg/kg, intra-gastrically) increased the expression of NRF2 and its downstream targets heme oxygenase-1 (HO-1), glutathione-S-transferase (GST), glutamate-cysteine ligase (GCL) and glutathione reductase (GR) consistently in spleen, thymus, as well as peripheral blood mononuclear cells (PBMCs), as early as treatment from 6h. Arsenic was also detected to up-regulate the mRNA levels of Hmox1, NAD(P)H: quinine oxidoreductase 1 (Nqo1), Gclc and Gclm in spleen and thymus. Besides, we detected the enhancement of Kelch-like ECH-associated protein (KEAP1) expression in these immune organs and immunocytes. What's more, our results also found the imbalanced oxidative redox status under the circumstances that arsenic activated NRF2 pathway, reflected by the generation of lipid peroxidation, as well as the reduction of antioxidative capacities in both spleen and thymus. Taken together, our results here strongly suggested the expression and activation of NRF2 pathway by acute arsenic exposure in immune system in vivo. Further studies are being investigated to explore the possible roles and functions of NRF2 pathway stimulation in the regulation of immune responses of this metalloid.

  4. 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

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

    PubMed

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

    2016-01-21

    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 simulations as a

  6. Nuclear Cardiology Practices and Radiation Exposure in the Oceania Region: Results From the IAEA Nuclear Cardiology Protocols Study (INCAPS).

    PubMed

    Biswas, Sinjini; Better, Nathan; Pascual, Thomas N B; Mercuri, Mathew; Vitola, João V; Karthikeyan, Ganesan; Westcott, James; Alexánderson, Erick; Allam, Adel H; Al-Mallah, Mouaz H; Bom, Henry Hee-Seung; Bouyoucef, Salah E; Flotats, Albert; Jerome, Scott; Kaufman, Philip A; Lele, Vikram; Luxenburg, Osnat; Mahmarian, John J; Shaw, Leslee J; Underwood, S Richard; Rehani, Madan; Kashyap, Ravi; Dondi, Maurizio; Paez, Diana; Einstein, Andrew J

    2017-01-01

    There is concern about radiation exposure with radionuclide myocardial perfusion imaging (MPI). This sub-study of the International Atomic Energy Agency (IAEA) Nuclear Cardiology Protocols Study reports radiation doses from MPI, and use of dose-optimisation protocols in Australia and New Zealand (ANZ), and compares them with data from the rest of the world. Data were collected from 7911 MPI studies performed in 308 laboratories worldwide in one week in 2013, including 439 MPI studies from 34 ANZ laboratories. For each laboratory, effective radiation dose (ED) and a quality index (QI) score (out of 8) based on pre-specified "best practices" was determined. In ANZ patients, ED ranged from 0.9-17.9 milliSievert (mSv). Median ED was similar in ANZ compared with the rest of the world (10.0 (IQR: 6.5-11.7) vs. 10.0 (IQR 6.4-12.6, P=0.15), as were mean QI scores (5.5±0.7 vs. 5.4±1.3, P=0.84). Use of stress-only imaging (17.6% vs. 31.8% of labs, P=0.09) and weight-based dosing of technetium-99m (14.7% vs. 30.3%, P=0.07) was lower in ANZ compared with the rest of the world but this difference was not statistically significant. Median ED was significantly lower in metropolitan versus non-metropolitan laboratories (10.1 mSv vs. 11.6 mSv, P<0.01), although mean QI scores were similar (5.4±0.8 vs. 5.5±0.7, P=0.75). Across ANZ, there is variability in ED from MPI, and use of radiation safety practices, particularly between metropolitan and non-metropolitan laboratories. Overall, ANZ laboratories have a similar median ED to laboratories in the rest of the world. Copyright © 2016 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.

  7. Acute retinal necrosis (ARN) in the context of neonatal HSV-2 exposure and subconjunctival dexamethasone: case report and literature review.

    PubMed

    McGrath, Lindsay; Woods, Marion; Lee, Lawrence; Conrad, Diana

    2013-01-01

    HSV-2 is an important cause of the acute retinal necrosis (ARN) syndrome in younger patients. We describe an atypical case of HSV-2 ARN in the context of neonatal exposure and subconjunctival steroid injection. Clinicians should be aware of the association of neonatal or congenital exposure to HSV-2 as a risk factor for this disease because early treatment may improve outcome and/or avoid involvement of both eyes.

  8. Behavioral and Physiological Responses to Nicotine Patch Administration Among Nonsmokers Based on Acute and Chronic Secondhand Tobacco Smoke Exposure.

    PubMed

    Okoli, Chizimuzo; Kodet, Jonathan; Robertson, Heather

    2016-01-01

    Despite the large amount that is known about the physical health effects of secondhand tobacco smoke (SHS) exposure, little is known about the behavioral health effects. Nicotine, the principle psychoactive substance in SHS, elicits subjective mood and physiological responses in nonsmokers. However, no studies have examined the subjective mood or physiological responses to nicotine in nonsmokers while accounting for prior chronic or acute SHS exposure. A 7-mg nicotine patch was administered to 17 adult nonsmokers for 2 hr. Main outcome measures obtained at ½ hr, 1 hr, and 2 hr were subjective behavioral drug effects (based on eleven 10-cm Visual Analog Scales [VASs]) and the physiological measures of heart rate, blood pressure, and serum nicotine levels. Analysis of outcome data was based on participants' chronic (using hair nicotine) or acute (using saliva cotinine) SHS exposure. Greater chronic SHS exposure was negatively associated with pleasurable responses to nicotine administration ("drug feels good" score at 2-hr time point, Spearman's ρ = -.65, p < .004), whereas greater acute SHS exposure was associated with positive responses ("like feeling of drug" score at 2-hr time point, Spearman's ρ = .63, p < .01). There were no associations between chronic or acute exposure and physiological changes in response to nicotine administration. The findings of this study may be useful in providing preliminary empirical data for future explorations of the mechanism whereby SHS exposure can influence behavioral outcomes in nonsmokers. Such studies can inform future interventions to reduce the physical and behavioral health risks associated with SHS exposure. © The Author(s) 2015.

  9. [Experimental estimation of thermogenic levels of acute microwave exposure for different animal species].

    PubMed

    Kolganova, O I; Drozd, A I; Zhavoronkov, L P; Baranov, V D; Glushakova, V S; Panferova, T A

    2000-01-01

    In experiments on laboratory animals it was found the different patterns of reactions in response to acute thermogenic 7 GHz CW microwave exposures. The effects were related specifically to the intensity of the field. SAR equal 0.5-0.7 power of basal metabolism of different species did not result in increase of body temperature. At SARs over intensity of basal metabolism (up to 1.5-2.0 basal metabolism for the mice and for the rats and up to 1.5 for the rabbits) the "stepped" pattern of body heating with periods of rectal temperature stabilization was observed. This results may have implications for prognostic estimation of dose-temporal limits of endurable intensities of microwaves.

  10. Oral exposure to Phytomonas serpens attenuates thrombocytopenia and leukopenia during acute infection with Trypanosoma cruzi.

    PubMed

    da Silva, Rosiane V; Malvezi, Aparecida D; Augusto, Leonardo da Silva; Kian, Danielle; Tatakihara, Vera Lúcia H; Yamauchi, Lucy M; Yamada-Ogatta, Sueli F; Rizzo, Luiz V; Schenkman, Sergio; Pinge-Filho, Phileno

    2013-01-01

    Mice infected with Trypanosoma cruzi, the agent of Chagas disease, rapidly develop anemia and thrombocytopenia. These effects are partially promoted by the parasite trans-sialidase (TS), which is shed in the blood and depletes sialic acid from the platelets, inducing accelerated platelet clearance and causing thrombocytopenia during the acute phase of disease. Here, we demonstrate that oral immunization of C57BL/6 mice with Phytomonas serpens, a phytoflagellate parasite that shares common antigens with T. cruzi but has no TS activity, reduces parasite burden and prevents thrombocytopenia and leukopenia. Immunization also reduces platelet loss after intraperitoneal injection of TS. In addition, passive transfer of immune sera raised in mice against P. serpens prevented platelet clearance. Thus, oral exposure to P. serpens attenuates the progression of thrombocytopenia induced by TS from T. cruzi. These findings are not only important for the understanding of the pathogenesis of T. cruzi infection but also for developing novel approaches of intervention in Chagas disease.

  11. Delayed loss of cone and remaining rod photoreceptor cells due to impairment of choroidal circulation after acute light exposure in rats.

    PubMed

    Tanito, Masaki; Kaidzu, Sachiko; Anderson, Robert E

    2007-04-01

    To examine the long-term effects of acute photooxidative stress in the retina, retinal pigment epithelium (RPE), and choroid. Albino rats injected with either the protective antioxidant phenyl-N-tert-butylnitrone (PBN) or saline 30 minutes before exposure to 5 klx white fluorescent light for 6 hours were kept for up to 3 months in 5 lux cyclic light. Electroretinograms were recorded, and the outer nuclear layer (ONL) and the choroidal thickness and area were measured after hematoxylin-eosin (H&E) staining. The expression of rod, cone, and RPE cell markers was detected by Western blotting, and apoptosis was analyzed by TUNEL staining. Oxidative stress was analyzed by immunohistochemistry against 4-hydroxynonenal (4-HNE)-modified proteins. Retinal and choroidal ultrastructures were observed by transmission electron microscopy (TEM). Choroidal circulation was analyzed by in vivo staining of the choroidal layer by trypan blue. In the saline-injected animals, TUNEL- and 4-HNE-labeling in the ONL, RPE, and choroid were higher 24 hours and 7 days after light exposure, and ERG amplitude, ONL and choroidal thickness and area, and rhodopsin and RPE65 expression were lower 7 or more days after light exposure than in phenyl-N-tert-butylnitrone (PBN)-injected animals. In the saline-injected animals, the expression of mid-wavelength opsin and the presence of cone cells in the ONL and the choroidal circulation were preserved for 7 days after light exposure but started to decrease by 1 month and continued to decrease for 3 months after light exposure. An increase in TUNEL-positive cells was observed in the ONL at the inferior peripheral retina, just behind the iris, by 3 months after light exposure. Delayed loss of cone cells, remaining rod cells, and choroidal circulation were counteracted by PBN treatment. Although cone cells are resistant to cell damage induced by acute photooxidative stress, progressive loss of cone cells continued for up to 3 months after light exposure

  12. Effect of acute exposure to moderate altitude on muscle power: hypobaric hypoxia vs. normobaric hypoxia.

    PubMed

    Feriche, Belén; García-Ramos, Amador; Calderón-Soto, Carmen; Drobnic, Franchek; Bonitch-Góngora, Juan G; Galilea, Pedro A; Riera, Joan; Padial, Paulino

    2014-01-01

    When ascending to a higher altitude, changes in air density and oxygen levels affect the way in which explosive actions are executed. This study was designed to compare the effects of acute exposure to real or simulated moderate hypoxia on the dynamics of the force-velocity relationship observed in bench press exercise. Twenty-eight combat sports athletes were assigned to two groups and assessed on two separate occasions: G1 (n = 17) in conditions of normoxia (N1) and hypobaric hypoxia (HH) and G2 (n = 11) in conditions of normoxia (N2) and normobaric hypoxia (NH). Individual and complete force-velocity relationships in bench press were determined on each assessment day. For each exercise repetition, we obtained the mean and peak velocity and power shown by the athletes. Maximum power (Pmax) was recorded as the highest P(mean) obtained across the complete force-velocity curve. Our findings indicate a significantly higher absolute load linked to P(max) (∼ 3%) and maximal strength (1 RM) (∼ 6%) in G1 attributable to the climb to altitude (P<0.05). We also observed a stimulating effect of natural hypoxia on P(mean) and P(peak) in the middle-high part of the curve (≥ 60 kg; P<0.01) and a 7.8% mean increase in barbell displacement velocity (P<0.001). No changes in any of the variables examined were observed in G2. According to these data, we can state that acute exposure to natural moderate altitude as opposed to simulated normobaric hypoxia leads to gains in 1 RM, movement velocity and power during the execution of a force-velocity curve in bench press.

  13. Effects of Acutely Intermittent Hypoxic Exposure on Running Economy and Physical Performance in Basketball Players.

    PubMed

    Kilding, Andrew E; Dobson, Bryan P; Ikeda, Erika

    2016-07-01

    Kilding, AE, Dobson, BP, and Ikeda, E. Effects of acutely intermittent hypoxic exposure on running economy and physical performance in basketball players. J Strength Cond Res 30(7): 2033-2042, 2016-The aim of this study was to determine the effect of short duration intermittent hypoxic exposure (IHE) on physical performance in basketball players. Using a single-blind placebo-controlled group design, 14 trained basketball players were subjected to 15 days of passive short duration IHE (n = 7), or normoxic control (CON, n = 7), using a biofeedback nitrogen dilution device. A range of physiological, performance, and hematological variables were measured at baseline, and 10 days after IHE. After intervention, the IHE group, relative to the CON group, exhibited improvements in the Yo-Yo intermittent recovery level 1 (+4.8 ± 1.6%; effect size [ES]: 1.0 ± 0.4) and repeated high-intensity exercise test performance (-3.5 ± 1.6%; ES: -0.4 ± 0.2). Changes in hematological parameters were minimal, although soluble transferrin receptor increased after IHE (+9.2 ± 10.1%; ES: 0.3 ± 0.3). Running economy at 11 km·h (-9.0 ± 9.7%; ES: -0.7 ± 0.7) and 13 km·h was improved (-8.2 ± 6.9%; ES: -0.7 ± 0.5), but changes to V[Combining Dot Above]O2peak, HRpeak, and lactate were unclear. In summary, acutely IHE resulted in worthwhile changes in physical performance tests among competitive basketball players. However, physiological measures explaining the performance enhancement were in most part unclear.

  14. Effect of Acute Exposure to Moderate Altitude on Muscle Power: Hypobaric Hypoxia vs. Normobaric Hypoxia

    PubMed Central

    Feriche, Belén; García-Ramos, Amador; Calderón-Soto, Carmen; Drobnic, Franchek; Bonitch- Góngora, Juan G.; Galilea, Pedro A.; Riera, Joan; Padial, Paulino

    2014-01-01

    When ascending to a higher altitude, changes in air density and oxygen levels affect the way in which explosive actions are executed. This study was designed to compare the effects of acute exposure to real or simulated moderate hypoxia on the dynamics of the force-velocity relationship observed in bench press exercise. Twenty-eight combat sports athletes were assigned to two groups and assessed on two separate occasions: G1 (n = 17) in conditions of normoxia (N1) and hypobaric hypoxia (HH) and G2 (n = 11) in conditions of normoxia (N2) and normobaric hypoxia (NH). Individual and complete force-velocity relationships in bench press were determined on each assessment day. For each exercise repetition, we obtained the mean and peak velocity and power shown by the athletes. Maximum power (Pmax) was recorded as the highest Pmean obtained across the complete force-velocity curve. Our findings indicate a significantly higher absolute load linked to Pmax (∼3%) and maximal strength (1RM) (∼6%) in G1 attributable to the climb to altitude (P<0.05). We also observed a stimulating effect of natural hypoxia on Pmean and Ppeak in the middle-high part of the curve (≥60 kg; P<0.01) and a 7.8% mean increase in barbell displacement velocity (P<0.001). No changes in any of the variables examined were observed in G2. According to these data, we can state that acute exposure to natural moderate altitude as opposed to simulated normobaric hypoxia leads to gains in 1RM, movement velocity and power during the execution of a force-velocity curve in bench press. PMID:25474104

  15. Experimental exposure to propylene glycol mist in aviation emergency training: acute ocular and respiratory effects

    PubMed Central

    Wieslander, G; Norback, D; Lindgren, T

    2001-01-01

    OBJECTIVES—Propylene glycol (PG) (1-2 propanediol; CAS No 57-55-6) is a low toxicity compound widely used as a food additive, in pharmaceutical preparations, in cosmetics, and in the workplace—for example, water based paints, de-icing fluids, and cooling liquids. Exposure to PG mist may occur from smoke generators in discotheques, theatres, and aviation emergency training. Propylene glycol may cause contact allergy, but there is sparse information on health effects from occupational exposure to PG.
METHODS—Non-asthmatic volunteers (n=27) were exposed in an aircraft simulator to PG mist over 1 minute, during realistic training conditions. Geometric mean concentration of PG was 309 mg/m3 (range 176-851 mg/m3), with the highest concentrations in the afternoon. The medical investigation was performed both before and after the exposure (within 15 minutes). It included an estimate of tear film stability break up time, nasal patency by acoustic rhinometry, dynamic spirometry, and a doctor's administered questionnaire on symptoms.
RESULTS—After exposure to PG mist for 1 minute tear film stability decreased, ocular and throat symptoms increased, forced expiratory volume in 1 second/forced vital capacity (FEV1/FVC) was slightly reduced, and self rated severity of dyspnoea was slightly increased. No effect was found for nasal patency, vital capacity (VC), FVC, nasal symptoms, dermal symptoms, smell of solvent, or any systemic symptoms. Those exposed to the higher concentrations in the afternoon had a more pronounced increase of throat symptoms, and a more pronounced decrease of tear film stability. In four subjects who reported development of irritative cough during exposure to PG, FEV1 was decreased by 5%, but FEV1 was unchanged among those who did not develop a cough. Those who developed a cough also had an increased perception of mild dyspnoea.
CONCLUSION—Short exposure to PG mist from artificial smoke generators may cause acute ocular and upper airway

  16. Exposing exposure: enhancing patient safety through automated data mining of nuclear medicine reports for quality assurance and organ dose monitoring.

    PubMed

    Ikuta, Ichiro; Sodickson, Aaron; Wasser, Elliot J; Warden, Graham I; Gerbaudo, Victor H; Khorasani, Ramin

    2012-08-01

    To develop and validate an open-source informatics toolkit capable of creating a radiation exposure data repository from existing nuclear medicine report archives and to demonstrate potential applications of such data for quality assurance and longitudinal patient-specific radiation dose monitoring. This study was institutional review board approved and HIPAA compliant. Informed consent was waived. An open-source toolkit designed to automate the extraction of data on radiopharmaceuticals and administered activities from nuclear medicine reports was developed. After iterative code training, manual validation was performed on 2359 nuclear medicine reports randomly selected from September 17, 1985, to February 28, 2011. Recall (sensitivity) and precision (positive predictive value) were calculated with 95% binomial confidence intervals. From the resultant institutional data repository, examples of usage in quality assurance efforts and patient-specific longitudinal radiation dose monitoring obtained by calculating organ doses from the administered activity and radiopharmaceutical of each examination were provided. Validation statistics yielded a combined recall of 97.6% ± 0.7 (95% confidence interval) and precision of 98.7% ± 0.5. Histograms of administered activity for fluorine 18 fluorodeoxyglucose and iodine 131 sodium iodide were generated. An organ dose heatmap which displays a sample patient's dose accumulation from multiple nuclear medicine examinations was created. Large-scale repositories of radiation exposure data can be extracted from institutional nuclear medicine report archives with high recall and precision. Such repositories enable new approaches in radiation exposure patient safety initiatives and patient-specific radiation dose monitoring.

  17. Acute effects of exposure to 1 mg/m(3) of vaporized 2-ethyl-1-hexanol in humans.

    PubMed

    Ernstgård, L; Norbäck, D; Nordquist, T; Wieslander, G; Wålinder, R; Johanson, G

    2010-04-01

    The objective was to assess acute effects from controlled exposure of volunteers to 2-ethyl-1-hexanol, a volatile organic compound that is often found in indoor air. Sixteen males and fourteen females were in random order exposed to 1 mg/m(3) of vapors of 2-ethyl-1-hexanol or to clean air (control exposure) in an exposure chamber during 2 h at rest. The subjects performed symptom ratings on Visual Analog Scales. During exposure to 2-ethyl-1-hexanol subjective ratings of smell and eye discomfort were minimally but significantly increased. Ratings of nasal irritation, throat irritation, headache, dyspnoea, fatigue, dizziness, nausea, and intoxication were not significantly affected. No exposure-related effects on measurement of blinking frequency by electromyography, measurement of the eye break-up time, vital staining of the eye, nasal lavage biomarkers, transfer tests, spirometric and rhinometric measures were seen. No differences in response were seen between sexes or between atopics and non-atopics. Practical Implications It is important to assess acute effects in volatile organic compounds like 2-ethyl-1-hexanol. 2-ethyl-1-hexanol is often found in indoor air generated by degradation of plastic building materials or in new buildings. There are associations between 2-ethyl-1-hexanol in indoor air and respiratory effects, eye irritation, headache, and blurred vision. A controlled chamber exposure study in acute effects was performed. In conclusion, this study showed weak subjective symptom of irritation in the eyes.

  18. Biophysical model for assessment of risk of acute exposures in combination with low level chronic irradiation

    NASA Astrophysics Data System (ADS)

    Smirnova, O. A.

    A biophysical model is developed which describes the mortality dynamics in mammalian populations unexposed and exposed to radiation The model relates statistical biometric functions mortality rate life span probability density and life span probability with statistical characteristics and dynamics of a critical body system in individuals composing the population The model describing the dynamics of thrombocytopoiesis in nonirradiated and irradiated mammals is also developed this hematopoietic line being considered as the critical body system under exposures in question The mortality model constructed in the framework of the proposed approach was identified to reproduce the irradiation effects on populations of mice The most parameters of the thrombocytopoiesis model were determined from the data available in the literature on hematology and radiobiology the rest parameters were evaluated by fitting some experimental data on the dynamics of this system in acutely irradiated mice The successful verification of the thrombocytopoiesis model was fulfilled by the quantitative juxtaposition of the modeling predictions and experimental data on the dynamics of this system in mice exposed to either acute or chronic irradiation at wide ranges of doses and dose rates It is important that only experimental data on the mortality rate in nonirradiated population and the relevant statistical characteristics of the thrombocytopoiesis system in mice which are also available in the literature on radiobiology are needed for the final identification of

  19. Acute and chronic effects of ferret odor exposure in Sprague-Dawley rats.

    PubMed

    Campeau, S; Nyhuis, T J; Sasse, S K; Day, H E W; Masini, C V

    2008-09-01

    This manuscript describes several behavioral and functional studies evaluating the capacity of ferret odors to elicit a number of acute and long-term responses in male Sprague-Dawley rats. Acute presentation elicits multiple responses, suggesting that ferret odor, likely from skin gland secretions, provides an anxiogenic-like stimulus in this strain of rats. Compared to cat odor, however, ferret odor did not produce rapid fear conditioning, a result perhaps attributable to methodological factors. Inactivation of the olfactory system and medial nucleus of the amygdala, combined with induction of the immediate-early gene c-fos, suggest the necessity of the accessory olfactory system in mediating the effects of ferret odor. Repeated exposures to ferret odor produce variable habituation of neuroendocrine and behavioral responses, perhaps indicative of the lack of control over the exact individual origin or concentration of ferret odor. Ferret odor induces rapid and long-term body weight regulation, thymic involution, adrenal hyperplasia and facilitation of the neuroendocrine response to additional challenges. It is argued that the use of such odors is exquisitely suited to investigate the brain regions coordinating anxiety-like responses and the long-term changes elicited by such stimuli.

  20. Elemental carbon exposure at residence and survival after acute myocardial infarction.

    PubMed

    von Klot, Stephanie; Gryparis, Alexandros; Tonne, Cathryn; Yanosky, Jeffrey; Coull, Brent A; Goldberg, Robert J; Lessard, Darleen; Melly, Steven J; Suh, Helen H; Schwartz, Joel

    2009-07-01

    Particulate air pollution has been consistently related to cardiovascular mortality. Some evidence suggests that particulate matter may accelerate the atherosclerotic process. Effects of within-city variations of particulate air pollution on survival after an acute cardiovascular event have been little explored. We conducted a cohort study of hospital survivors of acute myocardial infarction (MI) from the Worcester, MA, metropolitan area to investigate the long-term effects of within-city variation in traffic-related air pollution on mortality. The study builds on an ongoing community-wide investigation examining changes over time in MI incidence and case-fatality rates. We included confirmed cases of MI in 1995, 1997, 1999, 2001, and 2003. Long-term survival status was ascertained through 2005. A validated spatiotemporal land use regression model for traffic-related air pollution was developed and annual averages of elemental carbon at residence estimated. The effect of estimated elemental carbon on the long-term mortality of patients discharged after MI was analyzed using a Cox proportional hazards model, controlling for a variety of demographic, medical history, and clinical variables. Of the 3895 patients with validated MI, 44% died during follow-up. Exposure to estimated elemental carbon in the year of entry into the study was 0.44 microg/m on average. All-cause mortality increased by 15% (95% confidence interval = 0.03%-29%) per interquartile range increase in estimated yearly elemental carbon (0.24 microg/m) after the second year of survival. No association between traffic-related pollution and all-cause mortality was observed during the first 2 years of follow-up. Chronic traffic-related particulate air pollution is associated with increased mortality in hospital survivors of acute MI after the second year of survival.

  1. Caffeine improves performance in double poling during acute exposure to 2,000-m altitude.

    PubMed

    Stadheim, H K; Nossum, E M; Olsen, R; Spencer, M; Jensen, J

    2015-12-15

    There is limited research on the physiological effects of caffeine (CAF) ingestion on exercise performance during acute hypoxia. The aim of the present study was therefore to test the effect of placebo (PLA) and CAF (4.5 mg/kg) on double poling (DP) performance during acute hypoxia. Thirteen male subelite cross-country skiers (V̇o2max 72.6 ± 5.68 ml·kg(-1)·min(-1)) were included. Performance was assessed as 1) an 8-km cross-country DP time-trial (C-PT), and 2) time until task failure at a set workload equal to ∼90% of DP V̇o2max. Testing was carried out in a hypobaric chamber, at 800 mbar (Pio2: ∼125 mmHg) corresponding to ∼2,000 m above sea level in a randomized double-blinded, placebo-controlled, cross-over design. CAF improved time to task failure from 6.10 ± 1.40 to 7.22 ± 1.30 min (P < 0.05) and velocity the first 4 km (P < 0.05) but not overall time usage for the 8-km C-PT. During submaximal exercise subjects reported lower pain in arms and rate of perceived exertion (RPE) following CAF ingestion. Throughout C-PTs similar RPE and pain was shown between treatments. However, higher heart rate was observed during the CAF 8 km (187 ± 7 vs. 185 ± 7; P < 0.05) and 90% C-PT (185 ± 7 vs. 181 ± 9) associated with increased ventilation, blood lactate, glucose, adrenaline, decreased pH, and bicarbonate. The present study demonstrates for the first time that CAF ingestion improves DP time to task failure although not consistently time trial performance during acute exposure to altitude. Mechanisms underpinning improvements seem related to reduced pain RPE and increased heart rate during CAF C-PTs.

  2. Noninvasive Biomonitoring Approaches to Determine Dosimetry and Risk Following Acute Chemical Exposure: Analysis of Lead or Organophosphate Insecticide in Saliva

    SciTech Connect

    Timchalk, Chuck; Poet, Torka S.; Kousba, Ahmed A.; Campbell, James A.; Lin, Yuehe

    2004-04-01

    There is a need to develop approaches for assessing risk associated with acute exposures to a broad-range of chemical agents and to rapidly determine the potential implications to human health. Non-invasive biomonitoring approaches are being developed using reliable portable analytical systems to quantitate dosimetry utilizing readily obtainable body fluids, such as saliva. Saliva has been used to evaluate a broad range of biomarkers, drugs, and environmental contaminants including heavy metals and pesticides. To advance the application of non-invasive biomonitoring a microfluidic/ electrochemical device has also been developed for the analysis of lead (Pb), using square wave anodic stripping voltammetry. The system demonstrates a linear response over a broad concentration range (1 2000 ppb) and is capable of quantitating saliva Pb in rats orally administered acute doses of Pb-acetate. Appropriate pharmacokinetic analyses have been used to quantitate systemic dosimetry based on determination of saliva Pb concentrations. In addition, saliva has recently been used to quantitate dosimetry following exposure to the organophosphate insecticide chlorpyrifos in a rodent model system by measuring the major metabolite, trichloropyridinol, and saliva cholinesterase inhibition following acute exposures. These results suggest that technology developed for non-invasive biomonitoring can provide a sensitive, and portable analytical tool capable of assessing exposure and risk in real-time. By coupling these non-invasive technologies with pharmacokinetic modeling it is feasible to rapidly quantitate acute exposure to a broad range of chemical agents. In summary, it is envisioned that once fully developed, these monitoring and modeling approaches will be useful for accessing acute exposure and health risk.

  3. Public health activities for mitigation of radiation exposures and risk communication challenges after the Fukushima nuclear accident.

    PubMed

    Shimura, Tsutomu; Yamaguchi, Ichiro; Terada, Hiroshi; Robert Svendsen, Erik; Kunugita, Naoki

    2015-05-01

    Herein we summarize the public health actions taken to mitigate exposure of the public to radiation after the Fukushima accident that occurred on 11 March 2011 in order to record valuable lessons learned for disaster preparedness. Evacuations from the radiation-affected areas and control of the distribution of various food products contributed to the reduction of external and internal radiation exposure resulting from the Fukushima incident. However, risk communication is also an important issue during the emergency response effort and subsequent phases of dealiing with a nuclear disaster. To assist with their healing process, sound, reliable scientific information should continue to be disseminated to the radiation-affected communities via two-way communication. We will describe the essential public health actions following a nuclear disaster for the early, intermediate and late phases that will be useful for radiological preparedness planning in response to other nuclear or radiological disasters.

  4. Public health activities for mitigation of radiation exposures and risk communication challenges after the Fukushima nuclear accident

    PubMed Central

    Shimura, Tsutomu; Yamaguchi, Ichiro; Terada, Hiroshi; Robert Svendsen, Erik; Kunugita, Naoki

    2015-01-01

    Herein we summarize the public health actions taken to mitigate exposure of the public to radiation after the Fukushima accident that occurred on 11 March 2011 in order to record valuable lessons learned for disaster preparedness. Evacuations from the radiation-affected areas and control of the distribution of various food products contributed to the reduction of external and internal radiation exposure resulting from the Fukushima incident. However, risk communication is also an important issue during the emergency response effort and subsequent phases of dealiing with a nuclear disaster. To assist with their healing process, sound, reliable scientific information should continue to be disseminated to the radiation-affected communities via two-way communication. We will describe the essential public health actions following a nuclear disaster for the early, intermediate and late phases that will be useful for radiological preparedness planning in response to other nuclear or radiological disasters. PMID:25862700

  5. [Effect of training on treadmill performance, aerobic capacity and body reactions to acute cold exposure].

    PubMed

    Iakushkin, A V; Akimov, E B; Andreev, R S; Kalenov, Iu N; Kozlov, A V; Kuznetsova, O V; Son'kin, V D

    2014-01-01

    An attempt was made to test the hypothesis that regular physical activity at the anaerobic threshold is able to stimulate an increase in the amount of body fat brown or beige, which can manifest itself in increasing lactate utilization during exercise and increase the reactivity in response to acute regional cooling. The methods used are: ramp test, regional acute cold exposure, measurement of gas exchange, lactate and glucose in the blood, heart rate, and heart rate variability, blood pressure and respiration variability at rest and during standard functional tests; infrared thermal imaging, statistical methods of results analysis. Workout 10 physically active volunteers (7 males and 3 females) on a treadmill at a speed corresponding to 75-80% of the persona VO2max for 30 minutes 3 times per week at a fixed ambient temperature 21-22°C for 6 weeks resulted in a significant (from 19 to 39%) increase in test work duration but VO2max on average changed little. The increase in power of anaerobic threshold was associated with a sharp slowdown in the accumulation of lactate in progress of ramp test. Lactate utilization rate during the recovery period, on the contrary, increased. In general, significantly increased work efficiency at a test load. Not revealed noticeable changes in the condition and response to a standard functional tests of autonomic systems, as judged by heart rate variability, blood pressure and respiration variability at rest and during orthostatic tests and imposed breathing rhythm. The functional response of the body to acute cold exposure (1 minute cooling of the feet in ice water) is not changed after a cycle of training--either in terms of metabolism (oxygen consumption, etc.), or the dynamics of the skin temperature in areas of most probable location of brown adipose tissue (BAT). These data do not confirm the previously expressed (2010) hypothesis about the function of BAT as a universal homeostatic instrument in the body. Probably, if under

  6. Male adolescent rats display blunted cytokine responses in the CNS after acute ethanol or lipopolysaccharide exposure

    PubMed Central

    Doremus-Fitzwater, Tamara L.; Gano, Anny; Paniccia, Jacqueline E.; Deak, Terrence

    2015-01-01

    injected with LPS, no corresponding elevations were seen in adolescents after LPS; and (ii) neither adolescents nor adults demonstrated increases in plasma endotoxin concentrations following i.p. or i.g. ethanol administration. Analysis of BECs indicated that, for both routes of exposure, adolescents exhibited lower BECs than adults. Taken together, these data suggest that categorically different mechanisms are involved in the central cytokine response to antigen exposure versus ethanol administration. Furthermore, these findings confirm once again that acute ethanol intoxication is a potent activator of brain cytokines, and calls for future studies to identify the mechanisms underlying age-related differences in the cytokine response observed during ethanol intoxication. PMID:25708278

  7. Male adolescent rats display blunted cytokine responses in the CNS after acute ethanol or lipopolysaccharide exposure.

    PubMed

    Doremus-Fitzwater, Tamara L; Gano, Anny; Paniccia, Jacqueline E; Deak, Terrence

    2015-09-01

    , no corresponding elevations were seen in adolescents after LPS; and (ii) neither adolescents nor adults demonstrated increases in plasma endotoxin concentrations following i.p. or i.g. ethanol administration. Analysis of BECs indicated that, for both routes of exposure, adolescents exhibited lower BECs than adults. Taken together, these data suggest that categorically different mechanisms are involved in the central cytokine response to antigen exposure versus ethanol administration. Furthermore, these findings confirm once again that acute ethanol intoxication is a potent activator of brain cytokines, and calls for future studies to identify the mechanisms underlying age-related differences in the cytokine response observed during ethanol intoxication.

  8. Acute exposure to 2G phase shifts the rat circadian timing system

    NASA Technical Reports Server (NTRS)

    Hoban-Higgins, T. M.; Murakami, D. M.; Tandon, T.; Fuller, C. A.

    1995-01-01

    The circadian timing system (CTS) provides internal and external temporal coordination of an animal's physiology and behavior. In mammals, the generation and coordination of these circadian rhythms is controlled by a neural pacemaker, the suprachiasmatic nucleus (SCN), located within the hypothalamus. The pacemaker is synchronized to the 24 hour day by time cures (zeitgebers) such as the light/dark cycle. When an animal is exposed to an environment without time cues, the circadian rhythms maintain internal temporal coordination, but exhibit a 'free-running' condition in which the period length is determined by the internal pacemaker. Maintenance of internal and external temporal coordination are critical for normal physiological and psychological function in human and non-human primates. Exposure to altered gravitational environments has been shown to affect the amplitude, mean, and timing of circadian rhythms in species ranging from unicellular organisms to man. However, it has not been determined whether altered gravitational fields have a direct effect on the neural pacemaker, or affect peripheral parameters. In previous studies, the ability of a stimulus to phase shift circadian rhythms was used to determine whether a stimulus has a direct effect on the neural pacemaker. The present experiment was performed in order to determine whether acute exposure to a hyperdynamic field could phase shift circadian rhythms.

  9. Acute effects of AdvanceTM: a potential reduced exposure product for smokers

    PubMed Central

    Breland, A; Evans, S; Buchhalter, A; Eissenberg, T

    2002-01-01

    Design, setting, participants: Latin square ordered, three condition, laboratory based, crossover design with 20 smokers of light or ultra-light cigarettes (15 or more cigarettes/day). In each 2.5 hour condition, participants completed an 8-puff smoking bout from their own brand, AdvanceTM, or an unlit cigarette (that is, sham smoking) every 30 minutes for a total of four bouts. Main outcome measures: Subject rated measures of tobacco/nicotine withdrawal; carbon monoxide (CO), and heart rate; plasma nicotine concentrations. Results: Relative to own brand, AdvanceTM produced similar withdrawal suppression and heart rate increase, lower CO boost, and higher plasma nicotine concentrations. Conclusions: PREPs for smokers need to be evaluated using a comprehensive strategy that includes empirical examination of acute and long term effects. Adequate withdrawal suppression and potentially lower concentrations of CO associated with AdvanceTM use are positive factors, although higher nicotine concentrations do not constitute "reduced exposure". Overall, longer exposure periods are necessary to determine carcinogen delivery. PREP evaluation is complex and should be completed objectively. PMID:12432165

  10. Acute exposure to 2G phase shifts the rat circadian timing system

    NASA Technical Reports Server (NTRS)

    Hoban-Higgins, T. M.; Murakami, D. M.; Tandon, T.; Fuller, C. A.

    1995-01-01

    The circadian timing system (CTS) provides internal and external temporal coordination of an animal's physiology and behavior. In mammals, the generation and coordination of these circadian rhythms is controlled by a neural pacemaker, the suprachiasmatic nucleus (SCN), located within the hypothalamus. The pacemaker is synchronized to the 24 hour day by time cures (zeitgebers) such as the light/dark cycle. When an animal is exposed to an environment without time cues, the circadian rhythms maintain internal temporal coordination, but exhibit a 'free-running' condition in which the period length is determined by the internal pacemaker. Maintenance of internal and external temporal coordination are critical for normal physiological and psychological function in human and non-human primates. Exposure to altered gravitational environments has been shown to affect the amplitude, mean, and timing of circadian rhythms in species ranging from unicellular organisms to man. However, it has not been determined whether altered gravitational fields have a direct effect on the neural pacemaker, or affect peripheral parameters. In previous studies, the ability of a stimulus to phase shift circadian rhythms was used to determine whether a stimulus has a direct effect on the neural pacemaker. The present experiment was performed in order to determine whether acute exposure to a hyperdynamic field could phase shift circadian rhythms.

  11. A perspective on public concerns about exposure to fallout from the production and testing of nuclear weapons.

    PubMed

    Hoffman, F Owen; Apostoaei, A Iulian; Thomas, Brian A

    2002-05-01

    Exposures of the American public occurred nationwide from the testing of nuclear weapons in the United States, the Pacific, and the former Soviet Union. After decades of diminished public awareness on the subject of health risks resulting from exposure to fallout, the release of the National Cancer Institute's 1997 report on nationwide exposure to 131I from the Nevada Test Site (NTS) has led to renewed interest. Public requests for information are focused on individual and family health problems, the right to credible and full disclosure of information, and the need for medical care and assistance for exposure-related health problems. Public concerns have been raised regarding: (a) the lack of information on the potential health risks from exposure to all biologically significant radionuclides in fallout; (b) the lack of independent oversight that includes public participation; (c) governmental portrayal of exposures averaged over very large segments of the population without identification of much larger values for individuals or population subgroups likely to be at highest risk; and (d) a governmental response to known or suspected human exposures that consumes large periods of time and devotes considerable funding to various research-related activities before serious consideration is given to addressing health care responsibilities to exposed individuals. To some extent, these complaints and concerns are rooted in the legacy of government secrecy surrounding the development and testing of nuclear weapons, public distrust of government sources of information about radiation exposures and health risks, and the imposition of past exposures without informed consent. Members of the public participating in the oversight of dose reconstruction projects and epidemiologic studies are requesting information on the total impact from all relevant sources of exposure at each site that might contribute significantly to an individual's risk, including exposure to local

  12. Acute Exposure to Stress Improves Performance in Trace Eyeblink Conditioning and Spatial Learning Tasks in Healthy Men

    ERIC Educational Resources Information Center

    Duncko, Roman; Cornwell, Brian; Cui, Lihong; Merikangas, Kathleen R.; Grillon, Christian

    2007-01-01

    The present study investigated the effects of acute stress exposure on learning performance in humans using analogs of two paradigms frequently used in animals. Healthy male participants were exposed to the cold pressor test (CPT) procedure, i.e., insertion of the dominant hand into ice water for 60 sec. Following the CPT or the control procedure,…

  13. EFFECTS OF ACUTE EXPOSURE TO CONCENTRATED AMBIENT PARTICULATES ON CARDIOPULMONARY, THERMOREGULATORY, AND BIOCHEMICAL PARAMETERS IN OLD SPONTANEOUSLY HYPERTENSIVE RATS

    EPA Science Inventory


    EFFECTS OF ACUTE EXPOSURE TO CONCENTRATED AMBIENT PARTICULATES ON CARDIOPULMONARY, THERMOREGULATORY, AND BIOCHEMICAL PARAMETERS IN OLD SPONTANEOUSLY HYPERTENSIVE RATS. JP Nolan1, LB Wichers2, DW Winsett1, UP Kodavanti1, MCJ Schladweiler1, DL Costa1, and WP Watkinson1. 1US E...

  14. Acute Exposure to Stress Improves Performance in Trace Eyeblink Conditioning and Spatial Learning Tasks in Healthy Men

    ERIC Educational Resources Information Center

    Duncko, Roman; Cornwell, Brian; Cui, Lihong; Merikangas, Kathleen R.; Grillon, Christian

    2007-01-01

    The present study investigated the effects of acute stress exposure on learning performance in humans using analogs of two paradigms frequently used in animals. Healthy male participants were exposed to the cold pressor test (CPT) procedure, i.e., insertion of the dominant hand into ice water for 60 sec. Following the CPT or the control procedure,…

  15. EFFECTS OF ACUTE EXPOSURE TO CONCENTRATED AMBIENT PARTICULATES ON CARDIOPULMONARY, THERMOREGULATORY, AND BIOCHEMICAL PARAMETERS IN OLD SPONTANEOUSLY HYPERTENSIVE RATS

    EPA Science Inventory


    EFFECTS OF ACUTE EXPOSURE TO CONCENTRATED AMBIENT PARTICULATES ON CARDIOPULMONARY, THERMOREGULATORY, AND BIOCHEMICAL PARAMETERS IN OLD SPONTANEOUSLY HYPERTENSIVE RATS. JP Nolan1, LB Wichers2, DW Winsett1, UP Kodavanti1, MCJ Schladweiler1, DL Costa1, and WP Watkinson1. 1US E...

  16. Vasopressin Regulation and Renal Fluid and Electrolyte Handling in Rat Models of Acute and Chronic alcohol Exposure

    DTIC Science & Technology

    2004-10-01

    evaluating fluid and electrolyte regulating ability in models of acute and chronic alcohol exposure and alcohol withdrawal, and 2) uncovering mechanisms ...be used to define mechanisms behind alcohol effects better than study of humans because conditions of alcohol dosing, hydration status, and fluid...vasopressin receptor regulation, and have determined that altered renal responsiveness to vasopressin is the main mechanism behind fluid balance perturbations

  17. Acute exposure to 3-methylcholanthrene induces hepatic oxidative stress via activation of the Nrf2/ARE signaling pathway in mice.

    PubMed

    Jin, Yuanxiang; Miao, Wenyu; Lin, Xiaojian; Pan, Xiuhong; Ye, Yang; Xu, Minjie; Fu, Zhengwei

    2014-12-01

    Polycyclic aromatic hydrocarbons (PAHs) are the most common contaminants in the environment. The primary focus on the toxicity of PAHs is their ability to activate the aryl hydrocarbon receptor (AhR)-mediated pathway and lead to carcinogenesis in different organisms. However, the influence of PAHs on the antioxidant system in mammalian systems has received only limited attention. In the present study, we observed that the intraperitoneal injection of 100 mg/kg 3-methylcholanthrene (3MC) into mice significantly increased reactive oxygen species (ROS) levels and malondialdehyde (MDA) contents and decreased glutathione (GSH) contents and the activity of total antioxidant capacity (T-AOC), indicating that serious oxidative stress had been induced in the liver of mice. Then, the oxidative stress signal activated the nuclear factor erythroid 2-related factor 2/antioxidant response element (Nrf2/ARE) pathway by enhancing the mRNA levels of Nrf2, p38, and Erk2. Moreover, the mRNA levels of Nrf2/ARE target genes, including glutathione peroxidase (Gpx), glutathione reductase (GR), glutathione synthetase (GS), NAD(P)H: quinone oxidoreductase 1 (Nqo1), superoxide dismutase 1 (Sod1), and Sod2, increased significantly after treatment with 3MC for 24 hours. The hepatic levels of NQO1 and the activities of GR and GS were also significantly enhanced at 24 hours after 3MC treatment. Because the expression of NQO1 is co-regulated by Nrf2/ARE and AhR/XRE in mammalian tissues, NQO1 may play an important role in protecting against the oxidative stress induced by 3MC. Taken together, our findings suggested that acute exposure to 3MC altered the cellular redox balance in hepatocytes to trigger Nrf2-regulated antioxidant responses, which may represent an adaptive cell defense mechanism against the oxidative stress induced by PAHs.

  18. Assessment of toxic metal exposure following the Camelford water pollution incident: evidence of acute mobilization of lead into drinking water.

    PubMed

    Powell, J J; Greenfield, S M; Thompson, R P; Cargnello, J A; Kendall, M D; Landsberg, J P; Watt, F; Delves, H T; House, I

    1995-03-01

    Following the incident of acidic pollution of water by aluminium sulfate centred around Camelford in July 1988, we have carried out a retrospective analysis of the mobilization of toxic metals to residents of the area. An advanced nuclear technique was used to measure trace levels of elements within hair, thus, avoiding surface contamination. In contrast to controls, lead, but no other toxic metals, was consistently found within sections of hair that dated to mid-1988 from four residents; they must, therefore, have consumed this metal around the time of the incident. The source of this lead was probably local water pipe residue, and this was found on analysis to have a matrix specific to such soft-water areas that, prior to the incident, had slowly accumulated certain toxic metals such as cadmium and uranium and particularly lead. Lead is mobilized from such residues by acidic water and could, therefore, have heavily contaminated mains water after the incident. However, analyses of residents' plasma and whole blood, and of urine following a lead-chelation test, showed no evidence of either long-term increased body burdens of toxic metals or depletion of essential elements. In addition, we found no evidence of continued poor water quality in the area. In conclusion, during a short period following the pollution, some residents who consumed mains water would have been acutely exposed to lead and other toxic metals. Prediction of the scale of metal exposure to individuals was not possible owing to heterogeneity of the water distribution network, but long-term effects to residents from lead are not anticipated.(ABSTRACT TRUNCATED AT 250 WORDS)

  19. Effects of Acute Exposure to Moderate Altitude on Vascular Function, Metabolism and Systemic Inflammation

    PubMed Central

    Stöwhas, Anne-Christin; Latshang, Tsogyal D.; Lo Cascio, Christian M.; Lautwein, Sina; Stadelmann, Katrin; Tesler, Noemi; Ayers, Lisa; Berneis, Kaspar; Gerber, Philipp A.; Huber, Reto; Achermann, Peter; Bloch, Konrad E.; Kohler, Malcolm

    2013-01-01

    Background Travel to mountain areas is popular. However, the effects of acute exposure to moderate altitude on the cardiovascular system and metabolism are largely unknown. Objectives To investigate the effects of acute exposure to moderate altitude on vascular function, metabolism and systemic inflammation. Methods In 51 healthy male subjects with a mean (SD) age of 26.9 (9.3) years, oxygen saturation, blood pressure, heart rate, arterial stiffness, lipid profiles, low density lipoprotein (LDL) particle size, insulin resistance (HOMA-index), highly-sensitive C-reactive protein and pro-inflammatory cytokines were measured at 490 m (Zurich) and during two days at 2590 m, (Davos Jakobshorn, Switzerland) in randomized order. The largest differences in outcomes between the two altitudes are reported. Results Mean (SD) oxygen saturation was significantly lower at 2590 m, 91.0 (2.0)%, compared to 490 m, 96.0 (1.0)%, p<0.001. Mean blood pressure (mean difference +4.8 mmHg, p<0.001) and heart rate (mean difference +3.3 bpm, p<0.001) were significantly higher at 2590 m, compared to 490 m, but this was not associated with increased arterial stiffness. At 2590 m, lipid profiles improved (median difference triglycerides −0.14 mmol/l, p = 0.012, HDL +0.08 mmol/l, p<0.001, total cholesterol/HDL-ratio −0.25, p = 0.001), LDL particle size increased (median difference +0.45 nm, p = 0.048) and hsCRP decreased (median difference −0.18 mg/l, p = 0.024) compared to 490 m. No significant change in pro-inflammatory cytokines or insulin resistance was observed upon ascent to 2590 m. Conclusions Short-term stay at moderate altitude is associated with increased blood pressure and heart rate likely due to augmented sympathetic activity. Exposure to moderate altitude improves the lipid profile and systemic inflammation, but seems to have no significant effect on glucose metabolism. Trial Registration ClinicalTrials.gov NCT01130948 PMID:23936377

  20. Modeling the acute health effects of astronauts from exposure to large solar particle events.

    PubMed

    Hu, Shaowen; Kim, Myung-Hee Y; McClellan, Gene E; Cucinotta, Francis A

    2009-04-01

    Radiation exposure from Solar Particle Events (SPE) presents a significant health concern for astronauts for exploration missions outside the protection of the Earth's magnetic field, which could impair their performance and result in the possibility of failure of the mission. Assessing the potential for early radiation effects under such adverse conditions is of prime importance. Here we apply a biologically based mathematical model that describes the dose- and time-dependent early human responses that constitute the prodromal syndromes to consider acute risks from SPEs. We examine the possible early effects on crews from exposure to some historically large solar events on lunar and/or Mars missions. The doses and dose rates of specific organs were calculated using the Baryon radiation transport (BRYNTRN) code and a computerized anatomical man model, while the hazard of the early radiation effects and performance reduction were calculated using the Radiation-Induced Performance Decrement (RIPD) code. Based on model assumptions we show that exposure to these historical events would cause moderate early health effects to crew members inside a typical spacecraft or during extra-vehicular activities, if effective shielding and medical countermeasure tactics were not provided. We also calculate possible even worse cases (double intensity, multiple occurrences in a short period of time, etc.) to estimate the severity, onset and duration of various types of early illness. Uncertainties in the calculation due to limited data on relative biological effectiveness and dose-rate modifying factors for protons and secondary radiation, and the identification of sensitive sites in critical organs are discussed.

  1. Acute lung injury following inhalation exposure to nerve agent VX in guinea pigs.

    PubMed

    Wright, Benjamin S; Rezk, Peter E; Graham, Jacob R; Steele, Keith E; Gordon, Richard K; Sciuto, Alfred M; Nambiar, Madhusoodana P

    2006-05-01

    A microinstillation technique of inhalation exposure was utilized to assess lung injury following chemical warfare nerve agent VX [methylphosphonothioic acid S-(2-[bis(1-methylethyl)amino]ethyl) O-ethyl ester] exposure in guinea pigs. Animals were anesthetized using Telazol-meditomidine, gently intubated, and VX was aerosolized using a microcatheter placed 2 cm above the bifurcation of the trachea. Different doses (50.4 microg/m3, 70.4 micro g/m(m3), 90.4 microg/m(m3)) of VX were administered at 40 pulses/min for 5 min. Dosing of VX was calculated by the volume of aerosol produced per 200 pulses and diluting the agent accordingly. Although the survival rate of animals exposed to different doses of VX was similar to the controls, nearly a 20% weight reduction was observed in exposed animals. After 24 h of recovery, the animals were euthanized and bronchoalveolar lavage (BAL) was performed with oxygen free saline. BAL was centrifuged and separated into BAL fluid (BALF) and BAL cells (BALC) and analyzed for indication of lung injury. The edema by dry/wet weight ratio of the accessory lobe increased 11% in VX-treated animals. BAL cell number was increased in VX-treated animals compared to controls, independent of dosage. Trypan blue viability assay indicated an increase in BAL cell death in 70.4 microg/m(m3) and 90.4 microg/m(m3) VX-exposed animals. Differential cell counting of BALC indicated a decrease in macrophage/monocytes in VX-exposed animals. The total amount of BAL protein increased gradually with the exposed dose of VX and was highest in animals exposed to 90.4 microg/m(m3), indicating that this dose of VX caused lung injury that persisted at 24 h. In addition, histopathology results also suggest that inhalation exposure to VX induces acute lung injury.

  2. Proteomic Analysis of Bronchoalveolar Lavage Fluid: Effect of Acute Exposure to Diesel Exhaust Particles in Rats

    PubMed Central

    Lewis, John A.; Rao, K. Murali Krishna; Castranova, Vince; Vallyathan, Val; Dennis, William E.; Knechtges, Paul L.

    2007-01-01

    Background Inhalation of diesel exhaust particles (DEPs) is characterized by lung injury and inflammation, with significant increases in the numbers of polymorphonuclear leukocytes and alveolar macrophages. This influx of cellular infiltrates is associated with the activation of multiple genes, including cytokines and chemokines, and the production of reactive oxygen species. Objective The pathogenesis of the lung injury is not fully understood, but alterations in the presence or abundance of a number of proteins in the lung have been observed. Our objective in this study was to further characterize these changes and to ask whether additional changes could be discerned using modern proteomic techniques. Methods The present study investigates global alterations in the proteome of bronchoalveolar lavage fluid taken from rats 1, 7, or 30 days after exposure to 5, 35, or 50 mg/kg of animal weight of DEPs. Results Analysis by surface-enhanced laser desorption/ionization–time of flight mass spectrometry identified two distinct peaks that appeared as an acute response postexposure at all doses in all animals. We identified these two peaks, with mass to charge ratios (m/z) of 9,100 and 10,100, as anaphylatoxin C3a and calgranulin A by additional mass spectral investigation using liquid chromatography coupled to mass spectrometry. Conclusions With this approach, we found a number of inflammatory response proteins that may be associated with the early phases of inflammation in response to DEP exposure. Further studies are warranted to determine whether serum levels of these proteins could be markers of diesel exhaust exposure in workers. PMID:17520064

  3. Evaluating the acute effects of oral, non-combustible potential reduced exposure products marketed to smokers

    PubMed Central

    Cobb, CO; Weaver, MF; Eissenberg, T

    2011-01-01

    Background Non-combustible potential reduced exposure products (PREPs; eg, Star Scientific’s Ariva; a variety of other smokeless tobacco products) are marketed to reduce the harm associated with smoking. This marketing occurs despite an absence of objective data concerning the toxicant exposure and effects of these PREPs. Methods used to examine combustible PREPs were adapted to assess the acute effects of non-combustible PREPs for smokers. Methods 28 overnight abstinent cigarette smokers (17 men, 14 non-white) each completed seven, Latin-squared ordered, approximately 2.5 h laboratory sessions that differed by product administered: Ariva, Marlboro Snus (Philip Morris, USA), Camel Snus (RJ Reynolds, Winston-Salem, North Carolina, USA), Commit nicotine lozenge (GlaxoSmithKline; 2 mg), own brand cigarettes, Quest cigarettes (Vector Tobacco; delivers very low levels of nicotine) and sham smoking (ie, puffing on an unlit cigarette). In each session, the product was administered twice (separated by 60 min), and plasma nicotine levels, expired air CO and subjective effects were assessed regularly. Results Non-combustible products delivered less nicotine than own brand cigarettes, did not expose smokers to CO and failed to suppress tobacco abstinence symptoms as effectively as combustible products. Conclusions While decreased toxicant exposure is a potential indicator of harm reduction potential, a failure to suppress abstinence symptoms suggests that currently marketed non-combustible PREPs may not be a viable harm reduction strategy for US smokers. This study demonstrates how clinical laboratory methods can be used to evaluate the short-term effects of non-combustible PREPs for smokers. PMID:19346218

  4. Clinical and pathological manifestations of cardiovascular disease in rat models: the influence of acute ozone exposure.