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Sample records for accidental chronic exposure

  1. Chronic or accidental exposure of oysters to norovirus: is there any difference in contamination?

    Ventrone, Iole; Schaeffer, Julien; Ollivier, Joanna; Parnaudeau, Sylvain; Pepe, Tiziana; Le Pendu, Jacques; Le Guyader, Françoise S

    2013-03-01

    Bivalve molluscan shellfish such as oysters may be contaminated by human pathogens. Currently, the primary pathogens associated with shellfish-related outbreaks are noroviruses. This study was conducted to improve understanding of oyster bioaccumulation when oysters were exposed to daily contamination or one accidental contamination event, i.e., different modes of contamination. Oysters were contaminated with two representative strains of norovirus (GI.1 and GII.3) and then analyzed with real-time reverse transcription PCR. Exposure to a repeated virus dose for 9 days (mimicking a growing area subjected to frequent sewage contamination) led to an additive accumulation that was not significantly different from that obtained when the same total dose of virus was added all at once (as may happen after accidental sewage discharge). Similarly, bioaccumulation tests performed with mixed strains revealed additive accumulation of both viruses. Depuration may not be efficient for eliminating viruses; therefore, to prevent contaminated shellfish from being put onto the market, continuous sanitary monitoring must be considered. All climatic events or sewage failures occurring in production areas must be recorded, because repeated low-dose exposure or abrupt events may lead to similar levels of accumulation. This study contributes to an understanding of norovirus accumulation in oysters and provides suggestions for risk management strategies. PMID:23462089

  2. Epidemiology of accidental radiation exposures.

    Cardis, E

    1996-01-01

    Much of the information on the health effects of radiation exposure available to date comes from long-term studies of the atomic bombings in Hiroshima and Nagasaki. Accidental exposures, such as those resulting from the Chernobyl and Kyshtym accidents, have as yet provided little information concerning health effects of ionizing radiation. This paper will present the current state of our knowledge concerning radiation effects, review major large-scale accidental radiation exposures, and discu...

  3. Dosimetric significance of cytogenetic examinations in human accidental over exposures

    The damage to 13 workers following accidental exposures was assessed from lymphocyte chromosomal aberrations, and the results compared with those supplied by physical dosimetry and the clinical syndromes

  4. Lessons learned from accidental exposures in radiotherapy

    The medical use of radiation is unique in that patients are intentionally exposed to radiation. The aim in radiation therapy is twofold: to deliver a dose and dose distribution that is adequate for tumour control, but which also minimizes complications in normal tissues. In therapeutic applications, the doses are high and a deviation from the prescribed dose may have severe or even fatal consequences. There is therefore a great need to ensure adequate radiation protection and safety in radiotherapy by verifying that all personnel involved are appropriately trained for their duties, that the equipment used meets relevant international specifications for radiation safety and that safety culture is embedded in routine activities in radiotherapy departments. Many individuals must interact and work together on highly technical measurements and calculations, and therefore the potential for mistakes is great. A review of the mistakes shows that most are due to human error. The International Basic Safety Standards for Protection against Ionizing Radiation and the Safety of Radiation Sources (IAEA Safety Series No. 115) require that a prompt investigation be conducted whenever an accidental medical exposure of patients occurs. The report of the investigation is to be disseminated to the appropriate parties so that lessons can be learned to prevent similar accidents or mitigate their consequences in the future. This Safety Report is a collection of a large number of events that may serve as a checklist against which to test the vulnerability of a facility to potential accidents, and to provide a basis for improving safety in the use of radiation in medical applications. A further purpose of this report is to encourage readers to develop a questioning and learning attitude, adopt measures for the prevention of accidents, and prepare for mitigation of the consequences of accidents if they occur

  5. Cytogenetic biological dosimetry. Dose estimative in accidental exposure

    The methodology of cytogenetic biological dosimetry is studied. The application in estimation of dose in five cases of accidental exposure is reported. An hematological study and culture of lymphocytes is presented. (M.A.C.)

  6. Clinical study of lesions caused by accidental local exposure to ionizing radiations

    During the last few years the radiopathology service of the Curie Foundation has admitted more than a hundred patients who were followed and treated for irradiation or suspected irradiation after a work accident. Accidents followed by clinical symptoms account for about half the cases examined. Some of these clinical signs were benign whereas others developed very seriously, all possible conditions between these two extremes being represented. This report neglects cases of high total exposure and deals only with those of partial irradiation where local symptoms predominate, usually at the distal extremities of the upper limbs and exceptionally at the root or distal extremity of the lower limbs. Six clinical cases were selected as particularly revealing and are discussed below: accidental exposure of both hands to an iridium-192 source; chronic exposure to X-rays (left hand and right lower half-lip); accidental exposure of the right hand and antero-external face of the right thigh to a iridium-192 source; acute accidental exposure of the left hand to X-rays emitted under 50 kV; accidental exposure of both hands to cobalt-60 radiation; radiolesions of the left lower limb following a critical power excursion (gamma rays and neutrons)

  7. Quality control for handling of accidental blood exposures.

    Wijk, P.T. van; Pelk-Jongen, M.; Wijkmans, C.; Voss, A.; Schneeberger, P.M.

    2006-01-01

    A regional counselling service was established to handle all accidental blood exposures using a standardized protocol. Levels of risk were assessed using an algorithm. Accidents that posed a risk for the transmission of hepatitis B (HBV), hepatitis C (HCV) and human immunodeficiency virus (HIV) were

  8. The accidental exposure to ionizing radiations

    This article is divided in three parts, the first one gives the radioactivity sources, the doses and the effects, the second part is devoted to the medical exposures, the third part concerns the accidents and the biological effects of an irradiation the different syndromes ( the acute whole-body irradiation syndrome, the localized irradiation syndrome, the inflammatory syndrome, hematopoietic syndrome,neuro-vascular syndrome) are detailed. (N.C.)

  9. Accidental over-exposure from dental X-ray equipment

    A description is given of an unusual dental X-ray procedure which resulted in accidental over-exposure both to the dentist and to several of his patients when a short-circuit was present in newly-installed equipment. The short-circuit by-passed the exposure control and energized the tube for certain orientations of the X-ray tube. The dentist left the patients, who wore protective aprons, to initiate the exposure themselves, using the control button. Although the warning lights were on, the dentist was not present in the room during the exposure, and the over-exposures were only detected when the developed X-ray films were found to be completely blackened. A reconstruction of the procedure enabled estimates to be made of the dose equivalents to the dentist's body and to the skin of the head, the eyes and the gonads of the patients. The dentist had overlooked several of basic principles recommended in the Code of Practice for the Protection of Persons against Ionizing Radiations from Medical and Dental Use (1972). It is pointed out that incidents involving failure of dental equipment (usually the timer mechanism) are not infrequent. (U.K.)

  10. Nodular goiter after occupational accidental exposure to radiation

    Pisarev, M.A. [Radiobiology, National Atomic Energy Commission, Buenos Aires (Argentina); Human Biochemistry, Uninversity of Buenos Aires, School of Medicine, Buenos Aires (Argentina); Schnitman, M. [Center of Endocrinology and Metabolism, French Hospital C.Milstein, Buenos Aires (Argentina)

    2012-07-01

    In the present paper we present the consequences of an accidental occupational radiation exposure at a local hospital in Buenos Aires. Control at a local radiology service showed the lack of correct shielding in the X-ray equipment. The physicians and technicians (14 persons) exposed to radiation during 12 months were examined. The survey shows that: a) In 11 out of 14 radiation-exposed patients nodular goiter developed and an additional patient had diffuse goiter which means a goiter incidence of 85.7%; b) In 5 of the nodular goiter patients an increase in the size or the appearance of new nodules was observed along the follow-up period. No cancer was detected by FNA; c) Hypothyroidism was observed in 3/14 patients, and an additional patient had an abnormal TRH-TSH test, suggesting subclinical hypothyroidism; and d) Increased circulating antithyroid antibodies were found in one of the hypothyroid patients

  11. Dose assessment of an accidental exposure at the IPNS

    Seven different methods were used to estimate the dose rate to a female worker who was accidentally exposed in the neutron PHOENIX beamline at the IPNS. Theoretical and measured entrance dose ranged from 550 mrem/min to 2850 mrem/min. Theoretical estimates were based on a Monte Carlo simulation of a spectrum provided by IPNS (Crawford Spectrum). Dose measurements were made with TLDs on phantoms and with ionization chambers in a water phantom. Estimates of the whole body total effective dose equivalent (TEDE) rate ranged from 5.2 mrem/min to 840 mrem/min. Assumed and measured quality factors ranged from 2.6 to 11.8. Cytogenetic analyses of blood samples detected no positive exposure. The recommended TEDE rate was 158 mrem/min. The TEDE was 750 mrem

  12. Concept of radiological, medical and social protection of the population of Russia affected by accidental exposure

    Main principles of population radiation protection from various accidental exposure, including the Chernobyl accident, have been implemented in officially approved Concept ''On radiological, medical, social protection and rehabilitation of the Russian Federation population affected by accidental radiation exposure''. The concept includes basic principles of radiation protection, designation of regional radionuclide contaminated territories, records and registers of exposed persons, health protection and rehabilitation, socio-economic and legal aspects

  13. [Risk of acute hepatic insufficiency in children due to chronic accidental overdose of paracetamol (acetaminophen)

    Hameleers-Snijders, P.; Hogeveen, M.; Smeitink, J.A.M.; Kramers, C.; Draaisma, J.M.T.

    2007-01-01

    Two girls aged 4 and 3 years, respectively, experienced acute liver failure due to accidental ingestion of supratherapeutic doses of paracetamol (90 mg/kg/day or more). Recognition of chronic paracetamol intoxication as a cause of acute hepatic failure is often delayed. It is important to consider t

  14. Early diagnosis and monitoring of whole-body accidental exposure

    This paper deals with the handling of accidental, acute or protracted, whole-body overexposures. It is complementary to the report DPS 86/07 SEAPS previously published. The criteria for initial classification, as a function of the mean absorbed dose, the clinical and paraclinical evaluation, the monitoring methods and the treatments to undertake are described successively. The basic components of the therapy are the intensive care of the hematological syndrome with blood products transfusions and anti-infection prophylaxy. The indications and conditions for bone-marrow grafts are also discussed

  15. Individual dosimetry in planned, existing and accidental exposure situations

    There are three types of radiation exposure which include Planned exposure situations, Existing exposure situations and Emergency exposure situations which are defined as Situations that may occur during the operation of a planned situation, or from a malicious act, or from any other unexpected situation, and require urgent action in order to avoid or reduce undesirable consequences. A given individual may be exposed as a worker, and/or as a member of the public, and/or as a patient. Workers in medical professions involving radiation are occupationally exposed. For individual monitoring of exposed workers, Film badges or thermo luminescence dosimeters are in use. In cases where individual may be suspected to be contaminated internally, contamination monitors are used to monitor the site and whole body counters to monitor individuals. Members of the public are exposure to cosmic rays during air flights. Film badges were used to exposure of workers to NORM during maintenance work in old oil field. TLD is used for exposure workers in nuclear medicine department. Any radiation accident will add knowledge and experience. Accidents from lost, stolen or neglected sources are particularly special because the radiation exposure patterns of the individuals involved and the scenario of the accident are always different

  16. Adverse events in humans associated with accidental exposure to the livestock brucellosis vaccine RB51.

    Ashford, David A; di Pietra, Jennifer; Lingappa, Jairam; Woods, Christopher; Noll, Heather; Neville, Bridget; Weyant, Robbin; Bragg, Sandra L; Spiegel, Richard A; Tappero, Jordan; Perkins, Bradley A

    2004-09-01

    Brucella abortus strain RB51 vaccine, is an attenuated live bacterial vaccine that was licensed conditionally by the Center for Veterinary Biologics, Veterinary Services, Animal and Plant Health Inspection Service, USDA, on 23 February 1996, for vaccination of cattle in the United States. Accidental human inoculations can occur during vaccination of cattle, and previous live Brucella vaccines designed for cattle have been known to cause brucellosis in humans. The Centers for Disease Control and Prevention (CDC) established passive surveillance for accidental inoculation with the RB51 vaccine in the United States to determine if this veterinary vaccine is associated with human disease, to describe the circumstances of accidental inoculation, to evaluate the potential efficacy of post-exposure chemoprophylaxis, and to develop recommendations for post-exposure management following exposure to RB51. Reports were received from 26 individuals. Accidental exposure to RB51 occurred by needle stick injury in 21 people (81%), conjunctival spray exposure in four (15%), and spray exposure of an open wound in one (4%) individual. At least one systemic symptom was reported in 19 (73%) people, including three (12%) who reported persistent local reactions with systemic involvement. One case required surgery, and B. abortus strain RB51 was isolated from the wound of that individual. Seven cases reported no adverse event associated with accidental exposure. Nine cases reported previous exposure to Brucella vaccines, including one case who also reported a previous diagnosis of brucellosis following exposure to S19 vaccine. Accidental needle stick injuries and conjunctival or open wound exposures of humans with the RB51 vaccine are associated with both local and systemic adverse events in the United States that are consistent with brucellosis; however, it remains undetermined if strain RB51 vaccine can cause systemic brucellosis in humans. Early culture attempts on those exposed and

  17. Outcome of Accidental Exposure Prone to Blood Borne Viral Infections in an Educational Hospital

    Shahnaz Sali; Shabnam Tehrani; Sara Abulghasemi

    2016-01-01

    Background: The risk for transmission of blood-borne viruses (BBVs) such as Human immunodeficiency virus (HIV), hepatitis B virus (HBV) and hepatitis C virus (HCV) due to occupational exposure is a major concern in the health care setting.Materials and Methods: This study among 337 health care workers (HCWs) accidentally exposed to BBVs was carried out from January 2009 to March 2015. The data were reviewed in labbafinejhad hospital, Tehran, Iran.Results: 4 HCWs had exposure to HBS Ag positiv...

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

    Dörr Harald

    2011-11-01

    Full Text Available Abstract 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.

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

    Dörr Harald; Meineke Viktor

    2011-01-01

    Abstract 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 ab...

  20. Use of ubiquitous materials for the estimation of accidental exposures

    Incidents involving unexpected radiation exposure do take place due to human error, equipment failure or other reasons in spite of regulatory systems being in place. Medical physicists who are also radiation safety officers (RSO) of their institutions in several countries, like India, have the responsibility of radiation protection of the staff, carers and comforters of the patients, visitors and public at large, apart from ensuring patient-specific treatment planning for accurate dose delivery, adoption of optimized practices, and minimization of chances of radiation accidents in radiation therapy, radio-diagnostic, and nuclear medicine practices. Theft and mishandling of 137Cs teletherapy source in 1987 in Goiania (Brazil) in which 28 people suffered radiation burns and five people (three men, one woman, and one child) died and several other incidents demonstrated that mishandling of a source from a place like hospital cannot be ruled out. In the recent times, especially after terrorist attack on World Trade Center, New York, USA (on September 11, 2001), apprehensions of radiation terrorism and other malevolent uses (Dirty Bomb) of radioactive materials have considerably increased all over the world. To meet the situation of any radiation accident (due to external sources or the hospital-based sources), preparedness for dosimetry of the exposed persons in the quickest possible way becomes important for the implementation of the necessary follow-up procedures

  1. Oxycodone intoxication in an infant: accidental or intentional exposure?

    Levine, Barry; Moore, Karla A; Aronica-Pollak, Patricia; Fowler, David F

    2004-11-01

    A case is presented of a 10 month old male who went into cardiac arrest at a local store. The infant subsequently expired and was autopsied at the Office of the Chief Medical Examiner, State of Maryland. The only remarkable finding was the detection of oxycodone in the postmortem specimens; the blood and liver oxycodone concentrations were 0.6 mg/L and 1.6 mg/kg, respectively. Oxycodone was identified and quantitated by gas chromatography-nitrogen-phosphorus detection and confirmed by full scan electron ionization gas chromatography-mass spectrometry. The medical examiner ruled that the cause of death was oxycodone intoxication, and the manner of death was homicide. The key toxicologic question in this case was whether or not it was reasonable for the infant to be exposed to oxycodone exclusively through breast milk or through an alternate source. It was concluded that, at best, there were serious concerns about the likelihood of drug exposure through consumption of breast milk. PMID:15568714

  2. Monobath Films for Determining Accidental High-Level Exposures

    For remote reactor plants and others not provided with a permanent monitoring team to measure the dose to the personnel, the monobath method is recommended for handling film dosimeters. With this method it is possible to determine on the spot and without any loss of time whether persons have received a critical dose calling for medical care. The films recommended enable doses from about 10 to 2000 r to be detected by subjecting the films to an extremely simple monobath process. The density curves, their dependence on the radiation energy and on the temperature of the monobath developer are shown. The films are processed in daylight in a small device the size of a cigarette packet. By means of this device, which is described in detail, 40 film dosimeters can be processed and evaluated by one person in about one hour. The dose is determined by comparing the film blackening with that of a strip fitted into the device for this purpose. The monobath films are conveniently worn in small sturdy film badges which are insensitive to external influences. Film evaluation is made only if the exposure to radiation is likely to have caused a substantial personnel dose. The films have a lifetime of at least two years. The badges contain a lead filter rendering the film blackening largely independent of the radiation energy over the range from about 75 keV up to 3 MeV and more. If desired, the lead filter can be provided with a window so that part of the radiation can reach the film unattenuated. In this way it is possible to draw conclusions as to the type (gamma or beta rays) and energy of the radiation, both essential factors for a correct evaluation of the hazards. The described monobath film dosimeters can be used alone in the event of an incident or together with other film dosimeters of high sensitivity or with pocket dosimeters based on ionization under normal monitoring conditions. (author)

  3. Accidental phosgene gas exposure: A review with background study of 10 cases

    Arvind Kumar Vaish

    2013-01-01

    Full Text Available Here, authors present a review on clinical presentation and management of exposure of phosgene gas after reviewing the literature by searching with keywords phosgene exposure on Google, Cochrane, Embase and PubMed with a background of experience gained from 10 patients who were admitted to our institute after an accidental phosgene exposure in February 2011 nearby a city in India. Phosgene is a highly toxic gas, occupational workers may have accidental exposure. The gas can also be generated inadvertently during fire involving plastics and other chemicals and solvents containing chlorine, which is of concern to emergency responders. Phosgene inhalation may cause initially symptoms of respiratory tract irritation, patients feel fine thereafter, and then die of choking a day later because of build up of fluid in the lungs (delayed onset non-cardiogenic pulmonary edema. Phosgene exposure is associated with significant morbidity and mortality. Patients with a history of exposure should be admitted to the hospital for a minimum of 24 h for observation because of the potential for delayed onset respiratory failure and acute respiratory distress syndrome.

  4. Accidental internal exposure of all groups of Chernobyl nuclear power plant employees

    Accidental internal exposure of Chernobyl NPP employees has started from April, 1986 and it was found to be decreased to pre-accident level at the end of 1987. Significant number of people from all groups of staff and temporary employees were measured using whole body counters situated in Clinical Department of the Institute of Biophysics, which has represented the main body for medical assistance and expertise in these people including those, who suffered from acute radiation syndrome as well as the people engaged in all kinds of works at Chernobyl NPP site. Technical characteristics of the equipment and techniques used to assess the internal exposure are given. (author)

  5. Retinal photoreceptor focal disruption secondary to accidental Nd:YAG laser exposure.

    Milani, Paolo; Pierro, Luisa; Pece, Alfredo; Marino, Valerio; Scialdone, Antonio

    2011-10-01

    Retinal injuries caused by accidental laser exposure include retinal or vitreous hemorrhages, macular holes and edema. We describe the imaging of a bilateral macular lesion secondary to accidental Nd:YAG laser exposure. Observational case report. We performed color photography, fluorescein angiography and autofluorescence (AF) with a scanning laser ophthalmoscope, as well as time-domain and spectral-domain optical coherence tomography (OCT). After accidental exposure to a 1064 nm Nd:YAG laser, a patient experienced blurred vision in the left eye (LE) with visual acuity of 20/60. Color, fluorescein angiography and OCT imaging showed a retinal hemorrhage in the foveal area of the left eye and in the inferomacular region of the asymptomatic right eye. Steroid therapy was then administered, and 5 days later there was rapid improvement with progressive re-absorption of the hemorrhages and functional recovery. At 6 month follow-up, visual acuity was 20/20 in both eyes with unremarkable biomicroscopy, except for focal foveal retinal pigment epithelium (RPE) atrophy in the LE. In comparison to previous hemorrhages, OCT could visualize focal disruption of the photoreceptor IS/OS junction in both eyes. Due to different macular pigment distribution and lesion localization, 787 nm near-infrared AF depicted a small hypofluorescent spot in both eyes, whilst at 488 nm AF a black spot became evident in the right eye only. Despite the re-absorption of foveal hemorrhage and the functional recovery, AF and OCT imaging highlighted the persistence of small focal disruptions of the photoreceptor outer segments and RPE. PMID:22002418

  6. Multiple-Purpose Personal Dosimeter Suitable for Dosimetry of High Accidental Exposures

    The paper describes the personal dosimeter designed by the Commissariat à l'énergie atomique to permit evaluation of the doses received by workers liable to high accidental exposures. It consists of a film dosimeter plus a glass, threshold and activation detector pack. The film dosimeter consists of a case fitted with screens demarcating seven different areas of the film. The latter, which provides density measurements by reflection, consists of three emulsions of different sensitivities on a common base, so that a single development covers the dose range between 20 mr and 800 r. An NTA nuclear-emulsion, fast-neution dosimeter can be added. Two glass dosimeters of different characteristics are included to permit separate evaluation of gamma and thermal neutron radiation. The unit also possesses conventional threshold and activation detectors. (author)

  7. Medical documentation, bioanalytical evidence of an accidental human exposure to sulfur mustard and general therapy recommendations.

    Steinritz, Dirk; Striepling, Enno; Rudolf, Klaus-Dieter; Schröder-Kraft, Claudia; Püschel, Klaus; Hullard-Pulstinger, Andreas; Koller, Marianne; Thiermann, Horst; Gandor, Felix; Gawlik, Michael; John, Harald

    2016-02-26

    Sulfur mustard (SM) is a chemical warfare agent (CWA) that was first used in World War I and in several military conflicts afterwards. The threat by SM is still present even today due to remaining stockpiles, old and abandoned remainders all over the world as well as to its ease of synthesis. CWA are banned by the Chemical Weapons Convention (CWC) interdicting their development, production, transport, stockpiling and use and are subjected to controlled destruction. The present case report describes an accidental exposure of three workers that occurred during the destruction of SM. All exposed workers presented a characteristic SM-related clinical picture that started about 4h after exposure with erythema and feeling of tension of the skin at the upper part of the body. Later on, superficial blister and a burning phenomenon of the affected skin areas developed. Similar symptoms occurred in all three patients differing severity. One patient presented sustained skin affections at the gluteal region while another patient came up with affections of the axilla and genital region. Fortunately, full recovery was observed on day 56 after exposure except some little pigmentation changes that were evident even on day 154 in two of the patients. SM-exposure was verified for all three patients using bioanalytical GC MS and LC MS/MS based methods applied to urine and plasma. Urinary biotransformation products of the β-lyase pathway were detected until 5 days after poisoning whereas albumin-SM adducts could be found until day 29 underlining the beneficial role of adduct detection for post-exposure verification. In addition, we provide general recommendations for management and therapy in case of SM poisoning. PMID:26321678

  8. Occupational Exposures and Chronic Airflow Limitation

    Helen Dimich-Ward

    1996-01-01

    Full Text Available The recent literature was reviewed to evaluate whether chronic airflow limitation is associated with occupational exposures to dusts. Only those studies that controlled for the effects of smoking were included. There is compelling evidence that exposure to inorganic dusts, such as from coal and hardrock mining or asbestos, are associated with the development of chronic airflow limitation, independently of pneumoconiosis. Nonsmoking gold miners are particularly at high risk of airflow obstruction and emphysema. Findings from studies of organic dusts, such as exposures to wood, cotton, grain or other agricultural dusts, or to mixed dust exposures, were less consistent but tended to show positive dose-response associations. In the majority of studies, no statistical interaction was shown between dust exposures and smoking; however, the effects of the dust exposures were often more pronounced. An occupational history should be considered, in addition to a smoking history, as an integral part of an investigation of chronic airflow limitation in a patient.

  9. Accidental carbon monoxide poisoning presenting without a history of exposure: A case report

    Bennetto Luke

    2008-04-01

    Full Text Available Abstract Introduction Carbon monoxide poisoning is easy to diagnose when there is a history of exposure. When the exposure history is absent, or delayed, the diagnosis is more difficult and relies on recognising the importance of multi-system disease. We present a case of accidental carbon monoxide poisoning. Case presentation A middle-aged man, who lived alone in his mobile home was found by friends in a confused, incontinent state. Initial signs included respiratory failure, cardiac ischaemia, hypotension, encephalopathy and a rash, whilst subsequent features included rhabdomyolysis, renal failure, amnesia, dysarthria, parkinsonism, peripheral neuropathy, supranuclear gaze palsy and cerebral haemorrhage. Despite numerous investigations including magnetic resonance cerebral imaging, lumbar puncture, skin biopsy, muscle biopsy and electroencephalogram a diagnosis remained elusive. Several weeks after admission, diagnostic breakthrough was achieved when the gradual resolution of the patient's amnesia, encephalopathy and dysarthria allowed an accurate history to be taken for the first time. The patient's last recollection was turning on his gas heating for the first time since the spring. A gas heating engineer found the patient's gas boiler to be in a dangerous state of disrepair and it was immediately decommissioned. Conclusion This case highlights several important issues: the bewildering myriad of clinical features of carbon monoxide poisoning, the importance of making the diagnosis even at a late stage and preventing the patient's return to a potentially fatal toxic environment, and the paramount importance of the history in the diagnostic method.

  10. Determination of reduction in life expectancy from stochastic somatic fatalities after accidental radiation exposure

    In risk studies for plants of the nuclear industry usually the number of fatalities by radiation induced health effects are assessed. They are divided into 'early fatalities' (mortality by acute radiation syndrom) and 'late fatalities' (deaths due to leukemia and cancer). For the individuals as well as for the society as a whole both health effects are in principle of different significance because of the different times of death after irradiation. Risk assessments which give only the number of fatalities therefore show an uncomplete picture of the consequence because they do not consider the age of the individuals at the time of death. In this report the mathematical models for the computation of the individual and collective reduction of life expectancy from stochastic somatic effects after accidental releases of radioactivity are described. Computational results with regard to the age distribution of the population are presented for persons living during the nuclear accident and persons born afterwards. Thereby the exposure pathways, organs and nuclides ot the German Risk Study are treated separately. A raw estimation of the reduction in life expectancy due to the late fatalities calculated in this study is given. (orig.)

  11. Evaluation of health effects in Sequoyah Fuels Corporation workers from accidental exposure to uranium hexafluoride

    Urine bioassay measurements for uranium and medical laboratory results were studied to determine whether there were any health effects from uranium intake among a group of 31 workers exposed to uranium hexafluoride (UF6) and hydrolysis products following the accidental rupture of a 14-ton shipping cylinder in early 1986 at the Sequoyah Fuels Corporation uranium conversion facility in Gore, Oklahoma. Physiological indicators studied to detect kidney tissue damage included tests for urinary protein, casts and cells, blood, specific gravity, and urine pH, blood urea nitrogen, and blood creatinine. We concluded after reviewing two years of follow-up medical data that none of the 31 workers sustained any observable health effects from exposure to uranium. The early excretion of uranium in urine showed more rapid systemic uptake of uranium from the lung than is assumed using the International Commission on Radiological Protection (ICRP) Publication 30 and Publication 54 models. The urinary excretion data from these workers were used to develop an improved systemic recycling model for inhaled soluble uranium. We estimated initial intakes, clearance rates, kidney burdens, and resulting radiation doses to lungs, kidneys, and bone surfaces. 38 refs., 10 figs., 7 tabs

  12. Health safety planning for possible accidental exposures of workers and population in Italy

    Unforeseen radiation exposures may be caused by technical or human faults in the utilization of radioactive devices, namely radionuclide sources, as well as from the peaceful uses of nuclear energy; the first instance is in general the more common one. The paper discusses the principal basis for health intervention planning in the case of possible accidental exposures of workers and/or the population to ionizing radiation, also with reference to hypothetical accidents at nuclear power stations. For this last purpose an important aspect is the definition of the 'source term' problem. The main differences existing between 'conventional' and radiation emergencies in the pre-planning of technical and health safety operations are discussed. Even if the general organizational planning is based on similar operating structures, radiation emergencies require a somewhat different approach. Besides the specialized aspects of prophylaxis and therapy which are needed in these cases, radiation emergencies call for a comparison of the social cost, the possible health detriment induced by health-related countermeasures and the specific radiation risk in a single case. In many instances, furthermore, a key role may also be played by psychological factors. Following this philosophy, a flexible organization plan has been drawn up, which consists of three-steps as follows: (1) local and/or regional level; (2) national level; (3) European or international level. For the first two levels, besides the possibility of utilizing health services, there is provision to arrange them into structures of increasing complexity, using modular, integrated and fixed operative units to adapt the intervention to specific aspects of each accident or emergency. The third level is represented by the WHO International Centre of Radiopathology (ICR) in Paris. An official agreement was recently signed by the ENEA and the Centre. (author)

  13. Maximum permissible amounts of accidentally released tritium derived from an environmental experiment to meet dose limits for public exposure

    This paper reports that it is important in the design of future fusion reactors and associated facilities that incorporate passive safety to take account of the possible environmental impact of accidental tritium release. Reliable information on dose consequences can be obtained by evaluating urine samples from persons exposed to tritium. Translating the results of the environmental HT experiment performed in France in 1986 into worst-case exposure conditions, the effective dose equivalent to an individual with highest exposure at a distance of 800 m (typical for site boundaries) is ∼1 x 10-4 Sv per gram of tritium emitted as HT when inhalation and skin absorption are considered. From this value, maximum permissible amounts of accidentally released HT can be derived on the basis of regulatory or anticipated dose limits

  14. Biological dose estimation for accidental supra-high dose gamma-ray exposure

    Chen, Y., E-mail: yingchen29@yahoo.com.cn [Department of Radiation Toxicology and Oncology, Beijing Institute of Radiation Medicine, 27 Taiping Road, Haidian District, Beijing 100850 (China); Yan, X.K. [Department of Radiation Toxicology and Oncology, Beijing Institute of Radiation Medicine, 27 Taiping Road, Haidian District, Beijing 100850 (China); Department of Radiation Safety, Beijing Institute of Nuclear and Chemical Safety, 14 Guan-cun, Dongcheng District, Beijing 100077 (China); Du, J.; Wang, Z.D.; Zhang, X.Q.; Zeng, F.G.; Zhou, P.K. [Department of Radiation Toxicology and Oncology, Beijing Institute of Radiation Medicine, 27 Taiping Road, Haidian District, Beijing 100850 (China)

    2011-09-15

    To correctly estimate the biological dose of victims accidentally exposed to a very high dose of {sup 60}Co gamma-ray, a new dose-effect curve of chromosomal dicentrics/multicentrics and rings in the supra-high dose range was established. Peripheral blood from two healthy men was irradiated in vitro with doses of {sup 60}Co gamma-rays ranging from 6 to 22 Gy at a dose rate of 2.0 Gy/min. Lymphocytes were concentrated, cultured and harvested at 52 h, 68 h and 72 h. The numbers of dic + r were counted. The dose-effect curves were established and validated using comparisons with doses from the Tokai-mura accident and were then applied to two victims of supra-high dose exposure accident. The results indicated that there were no significant differences in chromosome aberration frequency among the different culture times from 52 h to 72 h. The 6-22 Gy dose-effect curve was fitted to a linear quadratic model Y = -2.269 + 0.776D - 7.868 x l0{sup -3}D{sup 2}. Using this mathematic model, the dose estimates were similar to data from Tokai-mura which were estimated by PCC ring. Whole body average doses of 9.7 Gy and 18.1 Gy for two victims in the Jining accident were satisfactorily given. We established and successfully applied a new dose-effect curve of chromosomal dicentrics plus ring (dic + r) after 6-22 Gy {gamma}-irradiation from a supra-high dose {sup 60}Co gamma-ray accident.

  15. Estimation of high radiation dose during accidental exposure using Calyculin - an induced premature chromosome condensation assay

    The conventional cytogenetic dosimetry, the gold standard chromosomal aberration assay fails to estimate high radiation dose exposure due to mitotic delay and severe leukopenia. Hence, there is a need to establish reliable, easier and quicker methods for biodosimetry. The Calyculin-A induced premature chromosome condensation (PCC) assay is being recommended as a rapid method for biodosimetry. The calyculin-A is a strong inhibitor of both PP1 and PP2A phosphoprotein phosphatases and therefore, has been suggested to be a more potent inducer of PCC compared to other protein phosphatases inhibitor okadaic acid and fostriecin. In the present study, we have estimated coefficients of dose response curves for three PCC aberrations using Calyculin-A for biodosimetry purpose. The modified method outlined by Roser Puig et al 2013 was used to conduct Calyculin-A induced PCC assay in human blood lymphocytes. Calyculin A treatment was given for last 1 hr of the 48 hr culture. Final concentration of the Calyculin A was 50 nM and the study was carried out in the dose range 2.5-20 Gy using 60Co gamma rays. The centric rings, acentric rings and fragments are separately analyzed. Results show a linear dose dependent increase with a slope of 0.047±0.001 Gy-1 (R2=0.99 and P<0.0001) for centric rings and 0.07±0.002 (R2=0.99 and P<0.0001) for centric rings combined with acentric rings. The dose response of excess PCC fragments shows a linear quadratic response up to 15 Gy and thereafter it saturated. The linear and quadratic coefficients for fragments are 0.089 ± 0.04 Gy-1 and 0.0173 ± 0.003 Gy-2 (with R2=0.99 and P=3.5184E-4) respectively. The PCC index was 62% for 0 Gy, 56% for 2.5 Gy, 69% for 5 Gy, 73% for 7.5 Gy, 64% for 10 Gy, 55% for 15 Gy and 43% for 20 Gy. Results indicate that Calyculin-A induced PCC assay provides very high PCC index compared to okadaic acid and gives valuable biodosimetric information in the case of high dose accidental exposure. (author)

  16. DIFFICULTY IN BREATHING DUE TO ACCIDENTAL EXPOSURE TO HYPOCHLORITE SOLUTION IN ENDODONTIC TREATMENTREATHING DUE TO ACCIDENTAL EXPOSURE TO HYPOCHLORITE SOLUTION IN ENDODONTIC TREATMENT

    Buddiwati Punta

    2006-04-01

    Full Text Available An important phase of endodontic treatment is the irrigation of the root canal system. Desirable functions of irrigation are antimicrobial activity, dissolution of necrotic tissue, and non toxicity to the periradicular tissue. Toxicity of NaOCl solution on vital tissue is still controversial. Severe complications may occur if this solution is inadvertently exposed to the oral mucosa, and it is very hazardous. The purpose of this paper is to caution dentists on the hazards of using NaOCl irrigation in endodontic treatment. A case is presented in which 2.5% NaOCl solution was accidentally streaming into the patient's throat because the irrigating needle was not securely attached to the syringe, with the result that the patient had difficulty in breathing. The patient was promptly taken to a pulmonologist, internist, and ENT. The patient was given dexamethasone 10 mg iv injection, delladryl 1 cc iv, and nebulizer with 1 ampoule of steroid, 1 ampoule of ventolin and 5 cc NaCl 3x within 24 hours, and after 24 hours the condition was increased. From this case it is concluded that the 2.5% NaOCl solution is very alkaline and irritating, resulting in deem of the larynx and plugging up of the respiratory system. Clinicians need to be cautious in using NaOCl solution to avoid endangering the patient's life.

  17. Modelling 14C transfer in terrestrial environments in response to chronic and accidental 14C releases.

    Le Dizès, S.

    2011-01-01

    Concern about the quantity of carbon-14 (14C) released for several decades from nuclear facilities has prompted several modelling approaches of 14C behaviour in the environment. The TOCATTA model aims at estimating 14C (and 3H) transfers in terrestrial ecosystems exposed to atmospheric 14C (and 3H) releases from nuclear facilities under normal operating or accidental conditions. The model belongs to the larger framework of the SYMBIOSE modelling and simulation platform that aims at assessing ...

  18. Suggested Methods for Assessment of Accidental External Exposure and Internal Contamination of Workers and their Medical Management

    Certain assumptions are given for the amount of fission products released from a research reactor after the occurrence of an accident. The size and location of radioactive cloud are assumed, and the corresponding external and internal exposures of workers are computed. A method is suggested for assessment of accidental external radiation dose based on experimental studies performed on the changes of quenching effect of plasma or sera as a.result of whole- body gamma-radiation ranging from 25-200 rems. For assessment of accidentally internally incorporated gamma emitters we suggest the standard chair whole-body counter technique which was found to detect reliably 1/100 of the maximum permissible body burden within eight minutes. It was also suggested that a separation method based on the use of absorption phenomena observed for Sephadex (gel resin) can be applied for quick determination of gross alpha activity in urine. For management of accidentally exposed workers to radiation doses of a lethal or sublethal nature, bone-marrow transplantation therapy and blood component therapy in sterile rooms is discussed in the light of experience gained from treatment of leukaemia with intensive chemotherapy. (author)

  19. Ferrofluid-associated Cutaneous Dyschromia: Discoloration of Hand and Fingers Following Accidental Exposure to Ferromagnetic Fluid

    Cohen, Philip R; Arfa, Kenneth S.

    2016-01-01

    Background: Ferrofluid is a colloidal suspension that usually consists of surfactant-coated nanoparticles of magnetite (Fe3O4) in a carrier liquid. Ferromagnetic fluid forms spikes when the liquid is exposed to a magnetic field. Purpose: The authors describe a man who developed temporary discoloration of his right palm and fingers after accidental cutaneous contact with ferrofluid and discuss some of the current and potential applications of this unique liquid. Methods: A 28-year-old man was ...

  20. Description of the SAFRAN Model for Evaluation of Public Exposure Resulting from Accidental Release of Airborne Radioactive Materials into the Atmosphere and User’s Guide. Annex II

    This document describes the method used in the SAFRAN tool for calculation of exposure arising from accidental release of airborne radioactive materials into the atmosphere. Model can be used for evaluation of public exposure to allow comparison with the relevant dose limiting criteria. The model is based on the public exposure evaluation concept as described in IAEA reports. While both these reports in primary addresses impacts arising from routine (e.g. long time permanent) releases, the concept employed can be adapted for assessment of impacts arising from accidental (e.g. short time) releases. Another source which has also been extensively used is the German Incident calculation bases

  1. Chromosome damage and clinical manifestation in a fetus and the mother after accidental 60Co exposure in Xinzhou

    The authors present the clinical effect and chromosome damage sustained by a fetus and the four months pregnant mother in an accidental 60Co exposure in November of 1992 in Xinzhou, Shanxi Province. The mother suffered from a moderate acute radiation sickness with ratardation of fetal development. After delivery, the infant's body length, body weight and head circumference were all lowered by three percentiles compared with the normals. Four months after the exposure, the assay of the mother's peripheral lymphocytes showed a chromosome aberration rate of 36%, while concomitant examination of the baby failed to reveal any chromosome abnormality although the sister chromatid exchange rate was remarkably higher than that of the mother and the normal control

  2. Urban "accidental" wetlands mediate water quality and heat exposure for homeless populations in a desert city

    Palta, M.

    2015-12-01

    In urban settings where humans interact in complex ways with ecosystems, there may be hidden or unanticipated benefits (services) or harm (disservices) conferred by the built environment. We examined interactions of a highly vulnerable population, the homeless, with urban waterways and wetlands in the desert city of Phoenix, Arizona, U.S.A. Climate change models project increases in heat, droughts, and extreme floods for the southwestern U.S. These projected changes pose a number of problems for sustainability and quality of future water supply, and the ability of human populations to mitigate heat stress and avoid fatalities. Urban wetlands that are created "accidentally" (by water pooling in abandoned areas of the landscape) have many structural (e.g., soils and hydrology) and functional (e.g., high denitrification) elements that mimic natural, unaltered aquatic systems. Accidental wetland systems in the dry bed of the Salt River, fed by storm and waste water from urban Phoenix, are located within economically depressed sections of the city, and show the potential for pollutant and heat mitigation. We used a mixed-method socio-ecological approach to examine wetland ecosystem functions and the ways in which homeless populations utilize Salt River wetlands for ecosystem services. Interviews and trash surveys indicated that homeless people are accessing and utilizing the wetlands as a source of running water, for sanitary and heat mitigation services, and for recreation and habitation. Environmental monitoring demonstrated that the wetlands can provide a reliable source of running water, nutrient and pathogen removal, heat mitigation, and privacy, but they may also pose a health risk to individuals coming in contact with the water through drinking or bathing. Whether wetlands provided a net benefit vs. harm varied according to site, season, and particular service, and several tradeoffs were identified. For example, heat is highest during the summer storm season

  3. Chronic fatigue syndrome following a toxic exposure.

    Racciatti, D; Vecchiet, J; Ceccomancini, A; Ricci, F; Pizzigallo, E

    2001-04-10

    Chronic fatigue syndrome (CFS) is a clinical entity characterized by severe fatigue lasting more than 6 months and other well-defined symptoms. Even though in most CFS cases the etiology is still unknown, sometimes the mode of presentation of the illness implicates the exposure to chemical and/or food toxins as precipitating factors: ciguatera poisoning, sick building syndrome, Gulf War syndrome, exposure to organochlorine pesticides, etc. In the National Reference Center for CFS Study at the Department of Infectious Diseases of 'G. D'Annunzio' University (Chieti) we examined five patients (three females and two males, mean age: 37.5 years) who developed the clinical features of CFS several months after the exposure to environmental toxic factors: ciguatera poisoning in two cases, and exposure to solvents in the other three cases. These patients were compared and contrasted with two sex- and age-matched subgroups of CFS patients without any history of exposure to toxins: the first subgroup consisted of patients with CFS onset following an EBV infection (post-infectious CFS), and the second of patients with a concurrent diagnosis of major depression. All subjects were investigated by clinical examination, neurophysiological and immunologic studies, and neuroendocrine tests. Patients exposed to toxic factors had disturbances of hypothalamic function similar to those in controls and, above all, showed more severe dysfunction of the immune system with an abnormal CD4/CD8 ratio, and in three of such cases with decreased levels of NK cells (CD56+). These findings may help in understanding the pathogenetic mechanisms involved in CFS. PMID:11327394

  4. Cross-sectional study on accidental occupational exposures amongst urban slum-based private medical practitioners

    Aniruddha A. Malgaonkar

    2015-12-01

    Full Text Available Background: This cross-sectional, complete enumeration study was conducted in an urban slum to determine the frequency of occupational exposure of private medical practitioners to patient body fluids and the remedial measures adopted following such events and also to examine their high-risk practices, personal protective measures, immunisation and training status in relation to occupational exposures. Methods: After Institutional Ethics Committee approval, private medical practitioners practising for and #8805; 1 year in the locality who gave written informed consent were interviewed in their own clinics using a pre-tested formatted questionnaire. Results: Of the 108 respondents interviewed, the majority were non-allopathic, male practitioners. The speciality-wise and gender-wise differences in training in occupational exposure were not significant (p=0.135. Prior to disposal, 10.18% cut needles while 26.85% disinfected needles with 1% hypochlorite solution (p=0.0001. 50.93% never bent or recapped needles (p=0.0008. Only 19.44% regularly used gloves while examining patients (p=0.0039. 41.66% were completely unimmunised against Hepatitis B (p=0.004, while only one female non-allopathic practitioner (0.92% had taken complete immunisation against tetanus (p<0.05. Of the 7.41% respondents who had history of needle stick injuries, only one female non-allopathic practitioner had reported occupational exposure. Those unaware about the need for post-exposure prophylaxis for occupational exposure and that anti-retroviral therapy was part of post-exposure prophylaxis constituted 87.96% and 95.37%, respectively. Conclusions: Reporting of occupational exposure, complete immunisation against hepatitis B and tetanus and use of personal protection was inadequate. Specialised hands-on training ought to be an integral component of continuing medical education for private medical practitioners. [Int J Res Med Sci 2015; 3(12.000: 3708-3713

  5. The accidental exposure to ionizing radiations; L'exposition accidentelle aux rayonnements ionisants

    NONE

    2001-07-01

    This article is divided in three parts, the first one gives the radioactivity sources, the doses and the effects, the second part is devoted to the medical exposures, the third part concerns the accidents and the biological effects of an irradiation the different syndromes ( the acute whole-body irradiation syndrome, the localized irradiation syndrome, the inflammatory syndrome, hematopoietic syndrome,neuro-vascular syndrome) are detailed. (N.C.)

  6. In vivo EPR dosimetry of accidental exposures to radiation: experimental results indicating the feasibility of practical use in human subjects

    Low frequency electron paramagnetic resonance (EPR) provides the potential advantage of making accurate and sensitive measurements of absorbed radiation dose in teeth in situ, i.e. without removing the teeth from the potential victim. The potential limiting factors for making such measurements are: (1) whether low frequency EPR is sufficiently sensitive to detect radiation-induced signal in human teeth; (2) whether sufficient sensitivity can be maintained under in vivo conditions. In this manuscript, we summarize results indicating that this approach is feasible. Using 1.2 GHz EPR spectroscopy, we found that the lower limit for these measurements in isolated human teeth is 0.2 Gy or lower. Measurements of radiation-induced EPR signals in the teeth of living rats were achieved with sufficient sensitivity to indicate that, when taking into consideration the larger mass of human teeth, similar measurements in human teeth in situ would provide sensitivity in the dose range for potential accidental exposures. We estimate that the current lower limit for detecting radiation doses in human teeth in situ (in vivo) is 0.5-1.0 Gy; this would be sufficient for determining if a person has been exposed to potentially life threatening doses of ionizing radiation. The limiting factor for sensitivity appears to be background signals rather than signal/noise, and there are feasible means to overcome this problem and further increase sensitivity. The additional instrumental developments required to make an effective in vivo EPR dosimetric spectrometer for the measurements in teeth in human subjects in situ, seem quite achievable

  7. Late health effects of chronic radiation exposure of bone marrow

    Yarmoshenko, Ilia V.; Malinovsky, Georgy P.; Konshina, Lidia G.; Zhukovsky, Michael V. [Institute of Industrial Ecology UB RAS, 620219, 20, Sophy Kovalevskoy St., Ekaterinburg (Russian Federation); Tuzankina, Irina A. [Institute of Immunology and Physiology UB RAS, 620049, 106, Pervomayskaya St., Ekaterinburg (Russian Federation)

    2014-07-01

    Accidental explosion of waste storage tank at former soviet plutonium production plant 'Mayak' in 1957 resulted in emission of considerable amount of radioactive substances to the atmosphere. Atmospheric transfer and fallout caused contamination of the environment by Sr-90 and short-lived radionuclides (East-Ural Radioactive Trace, EURT). Due to consumption of contaminated food and milk some internal organs were affected to relatively high radiation exposure. Archive data of causes of deaths of rural population of EURT northern part for period 1957-2000 were used to create the Register on causes of deaths. Register records related to the settlements where initial surface contamination by Sr-90 was above and below 3.7 kBq/m2 were included to exposed (4 844 records) and unexposed (6 158 records) group respectively. Basing on the Register the analysis of cancer and non-cancer health effects of radiation exposure was conducted. By estimating proportionate mortality ratios statistically significant excess mortality due to the groups of causes of death as follow was observed in exposed population: stomach, liver and cervix cancers; group consisted only of stomach cancer; non-cancer deceases of infectious etiology. Non-significant but remarkably high risk was observed for the following groups of causes of death: bone cancer; leukemia; liver cancer; cervix cancer. Insignificant, virtually zero risk was found for: non-gastrointestinal solid cancers; colon and lung cancers; non-infectious non-cancer deceases. At the same time, considerable radiation doses were absorbed in bone (mean bone surface dose about 0.1 Gy) and colon (mean dose about 0.07 Gy). Doses absorbed in other organs and tissues were negligible and amounted less than 0.01 Gy for most tissues. It can be seen that some disagreement between observed effects and absorbed doses is revealed. Most remarkable is the high excess risks of stomach, liver and cervix cancers as well as non-cancer deceases of

  8. Late health effects of chronic radiation exposure of bone marrow

    Accidental explosion of waste storage tank at former soviet plutonium production plant 'Mayak' in 1957 resulted in emission of considerable amount of radioactive substances to the atmosphere. Atmospheric transfer and fallout caused contamination of the environment by Sr-90 and short-lived radionuclides (East-Ural Radioactive Trace, EURT). Due to consumption of contaminated food and milk some internal organs were affected to relatively high radiation exposure. Archive data of causes of deaths of rural population of EURT northern part for period 1957-2000 were used to create the Register on causes of deaths. Register records related to the settlements where initial surface contamination by Sr-90 was above and below 3.7 kBq/m2 were included to exposed (4 844 records) and unexposed (6 158 records) group respectively. Basing on the Register the analysis of cancer and non-cancer health effects of radiation exposure was conducted. By estimating proportionate mortality ratios statistically significant excess mortality due to the groups of causes of death as follow was observed in exposed population: stomach, liver and cervix cancers; group consisted only of stomach cancer; non-cancer deceases of infectious etiology. Non-significant but remarkably high risk was observed for the following groups of causes of death: bone cancer; leukemia; liver cancer; cervix cancer. Insignificant, virtually zero risk was found for: non-gastrointestinal solid cancers; colon and lung cancers; non-infectious non-cancer deceases. At the same time, considerable radiation doses were absorbed in bone (mean bone surface dose about 0.1 Gy) and colon (mean dose about 0.07 Gy). Doses absorbed in other organs and tissues were negligible and amounted less than 0.01 Gy for most tissues. It can be seen that some disagreement between observed effects and absorbed doses is revealed. Most remarkable is the high excess risks of stomach, liver and cervix cancers as well as non-cancer deceases of infectious

  9. Sensitivity of Trout to Chronic Acute Exposure to Selenium

    Nielsen, Gunnar Gissel; Nielsen, M. Gissel

    1978-01-01

    Trout were exposed to selenite (Na2SeO3) solutions of varying concentrations (0.1-100 ppm Se) for periods of up to 4 wk. A chronic exposure to 0.1 ppm Se or less is non-lethal to trout. Lethality at higher concentrations depends on the length of exposure. Trout that survive for 10 days in tap...

  10. Application of the Alkaline Comet Assay and the Analysis of Structural Chromosome Aberrations in Assessment of Genetic Damage After Accidental Exposure to Ionising Radiation

    Full text: Living with the effects of low-level ionising radiation is one of the normal hazards of life. However, the effects of lower doses may not show up for years after exposure and are due to various changes in DNA molecules and chromosomes. Radiation-induced mutations seem to be brought about by the deletion of small pieces of chromosomes during the process of chromosome breakage and repair. Since chromosome damage is most likely to happen in dividing cells, ionising radiation usually cause cancer in those parts of the body where cells are actively dividing. Ionising radiation kills rapidly dividing cells, blood lymphocytes among them. People are exposed to high doses of ionising radiation when radiation accidents occur. The cytogenetical consequences of accidental exposure to gamma-radiation (radiation dose 221 mSv) were investigated by using alkaline Comet assay and the analysis of structural chromosomal aberrations (CA). Blood samples were repeatedly collected during one-year period after the accident. By using the Comet assay immediately after accidental exposure a high level of DNA damage was recorded. Although this level was decreasing over a one-year period, it was still elevated compared to normal values of DNA damage for unexposed persons. Immediately after the accident prevalence of CA (dicentrics, acentrics) over chromatid aberrations was recorded. However, one year afterwards only a few chromatid breaks were recorded. Our results confirmed usefulness of the alkaline Comet assay as a simple and sensitive technique for the biomonitoring of DNA damages, especially in the cases of accidental exposure to ionising radiation. (author)

  11. TELOMERASE AND CHRONIC ARSENIC EXPOSURE IN HUMANS

    Arsenic exposure has been associated with increased risk of skin, lung and bladder cancer in humans. The mechanisms of carcinogenesis are not well understood. Telomerase, a ribonucleoprotein containing human telomerase reverse transcriptase (hTERT), can extend telomeres of eukary...

  12. Description of the SAFRAN Models for Evaluation of Worker Exposure Resulting from Accidental Release of Airborne Radioactive Materials snd User’s Guide. Annex I

    This document describes the method used in the SAFRAN tool for the calculation of exposure arising from accidental release of airborne radioactive materials. Models can be used for evaluation of occupational exposure to allow comparison with the relevant dose limiting criteria. Presently, four models are available to address different exposure conditions. The first three are ‘no dilution’ model, ‘gradual mixing’ model and ‘complete mixing’ model. The fourth combined ‘gradual mixing / complete mixing’ model is a combination of the two last models and allows the user to run subsequently the ‘gradual mixing and ‘complete mixing’ models. Each of the models are created using Ecolego. Each of the models is described and their practical use is explained

  13. Impact of chronic and acute pesticide exposures on periphyton communities

    Aquatic ecosystems face variable exposure to pesticides, especially during floodings which are associated with short bursts of high contaminant concentrations that influence biological systems. A study was undertaken to highlight the impact of the herbicide diuron applied in mixture with the fungicide tebuconazole on natural periphyton during flooding events. Periphyton were grown in two series of two lotic outdoor mesocosms: one series was non-contaminated while the other was exposed to chronic contamination. After 4 weeks, one channel of each series was exposed to three successive pulses, with each pulse followed by one week of recovery. Impacts on periphyton were assessed by using Denaturing Gel Gradient Electrophoresis to characterize eukaryotic community structure. At a functional scale, photosynthetic efficiency was quantified during each pulse, and the induced tolerance to diuron was estimated by performing short-term inhibition tests based on photosynthetic efficiency. Moreover, pesticide concentrations in the water column and periphyton matrix were measured. Diuron was adsorbed in the periphyton during each pulse and desorbed 13 h after pulse end. The different pulses affected the eukaryotic community structures of the control biofilms, but not of the chronically exposed ones. During the first pulse, photosynthetic efficiency was correlated with pesticide concentration in the water phase, and there was no difference between periphyton from chronically contaminated channels and control channels. However, during the second and third pulses, the photosynthetic efficiency of periphyton chronically exposed to pesticides appeared to be less impacted by the acute pulsed exposure of pesticide. These changes were consistent with the acquisition of induced tolerance to diuron since only after the third pulse that periphyton from chronic channel became tolerant to diuron. Our experimental study indicates that the effects of pulsed acute exposures to pesticides on

  14. CHRONIC DEVELOPMENTAL LEAD EXPOSURE REDUCES NEUROGENESIS IN ADULT HIPPOCAMPUS.

    CHRONIC DEVELOPMENTAL LEAD EXPOSURE REDUCES NEUROGENESIS IN ADULT HIPPOCAMPUS. ME Gilbert1, ME Kelly2, S. Salant3, T Shafer1, J Goodman3 1Neurotoxicology Div, US EPA, RTP, NC, 27711, 2Children's Hospital, Philadelphia, PA, 19104, 3Helen Hayes Hospital, Haverstraw, NY, 10993. ...

  15. Segmental hair testing to disclose chronic exposure to psychoactive drugs.

    Marchei, Emilia; Palmi, Ilaria; Pichini, Simona; Pacifici, Roberta; Anton Airaldi, Ileana-Rita; Costa Orvay, Juan Antonio; García Serra, Joan; Bonet Serra, Bartolomé; García-Algar, Óscar

    2016-01-01

    This study presents the case of a 4-year-old healthy child admitted to the paediatric ward for suspected accidental intoxication due to ingestion of narcoleptic drugs (methylphenidate, sertraline and quetiapine), taken on a regular basis by his 8-year-old brother affected by Asperger syndrome.Intoxication can be objectively assessed by measurements of drugs and metabolites in biological matrices with short-term (blood and urine) or long-term (hair) detection windows. At the hospital, the child's blood and urine were analysed by immunoassay (confirmed by liquid chromatography-mass spectrometry), and sertraline and quetiapine and their metabolites were identified. The suspicion that the mother administered drugs chronically prompted the analysis of six, consecutive 2-cm segments of the child's hair, using ultra-high performance liquid chromatography-tandem mass spectrometry, thereby accounting for ingestion over the previous 12 months. Quetiapine was found in the first four segments with a mean concentration of 1.00 ng/mg ± 0.94 ng/mg hair while sertraline and its metabolite, desmethyl-sertraline, were found in all segments with a mean concentration of 2.65 ± 0.94 ng/mg and 1.50 ± 0.94 ng/mg hair, respectively. Hair analyses were negative for methylphenidate and its metabolite (ritalinic acid). Biological matrices testing for psychoactive drugs disclosed both acute and chronic intoxication with quetiapine and sertraline administered by the mother. PMID:27399225

  16. Assessment of risks associated to ionizing radiations: lung cancers after domestic radon exposure and thyroid cancers after accidental exposure to radioactive iodines

    The aim of this work is to develop a critical analysis of quantitative risk assessment in the field of ionizing radiation and to provide new estimates of attributable risks for particular situations of environmental exposure to ionizing radiation. This work is based on knowledge about dose-response relationships and ionizing radiation exposure of the general population. The work focuses on two different situations that both present an important interest for public health: lung cancer associated with domestic radon exposures (natural situation) and thyroid cancer associated with the Chernobyl accident fallout (accidental situation). The assessment of lung cancer risk associated with domestic radon exposure considers 10 dose-response relationships resulting from miner cohorts and case-control studies in the general population. A critical review of available data on smoking habits has been performed and allowed to consider the interactions between radon and tobacco. The exposure data come from measurements campaigns carried out since the beginning of the 1980 by the Institute for Radiation protection and Nuclear Safety and the Health General Directory in France. The French lung cancer mortality data are provided by the I.N.S.E.R.M.. Estimates of the number of attributable cancers are carried out for the whole country, stratified by 8 large regions (Z.E.A.T.) and by 96 departments for the year 1999 allowing to perform a sensibility analysis according to the geographical level of calculation. Uncertainties associated to risk coefficients and exposures have been quantified and it's impact on risk estimates is calculated. The estimated number of deaths attributable to domestic radon exposure ranges from 543 (90% uncertainty interval (U.I.): 75-1,097) to 3,108 (90% U.I.: 2,996-3,221). The corresponding risk fractions range from 2.2% (90% U.I.: 0.3%-4.4%) to 12.4% (90% U.I.: 11.9%-12.8%). The assessment of thyroid cancer risk in the most exposed area of France due to the

  17. Personnel Dosimetry for Radiation Accidents. Proceedings of a Symposium on Personnel Dosimetry for Accidental High-Level Exposure to External and Internal Radiation

    Accidents involving the exposure of persons to high levels of radiation have been few in number and meticulous precautions are taken in an effort to maintain this good record. When, however, such an accident does occur, a timely estimate of the dose received can be of considerable help to the physician in deciding whether a particular person requires medical treatment, and in selecting the most appropriate treatment. Individual dosimetry provides the physical basis for relating the observed effects to those in other accident cases, to other human data, and to data from animal experiments, thus providing an important aid to rational treatment and to the accumulation of a meaningful body of knowledge on the subject. It is most important therefore that, where there is a possibility of receiving high-level exposure, methods of personnel dosimetry should be available that would provide the dosimetric information most useful to the physician. Provision of good personnel dosimetry for accidental high-level exposure is in many cases an essential part of emergency planning because the information provided may influence emergency and rescue operations, and can lead to improved accident preparedness. Accordingly, the International Atomic Energy Agency and the World Health Organization jointly organized the Symposium on Personnel Dosimetry for Accidental High-Level Exposure to External and Internal Radiation for the discussion of such methods and for a critical review of the procedures adopted in some of the radiation accidents that have already occurred. The meeting was attended by 179 participants from 34 countries and from five other international organizations. The papers presented and the ensuing discussions are published in these Proceedings. It is hoped that the Proceedings will be of help to those concerned with the organization and development of wide-range personnel monitoring systems, and with the interpretation of the results provided

  18. Anxiogenic-like effects of chronic nicotine exposure in zebrafish.

    Stewart, Adam Michael; Grossman, Leah; Collier, Adam D; Echevarria, David J; Kalueff, Allan V

    2015-12-01

    Nicotine is one of the most widely used and abused legal drugs. Although its pharmacological profile has been extensively investigated in humans and rodents, nicotine CNS action remains poorly understood. The importance of finding evolutionarily conserved signaling pathways, and the need to apply high-throughput in vivo screens for CNS drug discovery, necessitate novel efficient experimental models for nicotine research. Zebrafish (Danio rerio) are rapidly emerging as an excellent organism for studying drug abuse, neuropharmacology and toxicology and have recently been applied to testing nicotine. Anxiolytic, rewarding and memory-modulating effects of acute nicotine treatment in zebrafish are consistently reported in the literature. However, while nicotine abuse is more relevant to long-term exposure models, little is known about chronic effects of nicotine on zebrafish behavior. In the present study, chronic 4-day exposure to 1-2mg/L nicotine mildly increased adult zebrafish shoaling but did not alter baseline cortisol levels. We also found that chronic exposure to nicotine evokes robust anxiogenic behavioral responses in zebrafish tested in the novel tank test paradigm. Generally paralleling clinical and rodent data on anxiogenic effects of chronic nicotine, our study supports the developing utility of zebrafish for nicotine research. PMID:25643654

  19. Hepatotoxic potential of combined toluene-chronic ethanol exposure

    Howell, S.R.; Christian, J.E.; Isom, G.E.

    1986-05-01

    The hepatoxic properties of concurrent chronic oral ethanol ingestion and acute toluene inhalation were evaluated. Male rats were maintained on ethanol-containing or control liquid diets for 29 days. Animals of each group were subjected to five 20-min exposures to 10 000 ppm toluene with 30 min of room air inhalation between exposures on days 22, 24, 26, and 28 of liquid diet feeding. Some of the ethanol-fed animals were withdrawn from ethanol 14 h before exposure. Ethanol-withdrawn animals displayed an increased sensitivity to the narcotic action of toluene. Animals were sacrificed and assays performed on day 29. Stress markers (plasma corticosterone, free fatty acid, and glucose) were not affected by treatments. A modest elevation in plasma aspartate amino-transferase occurred in non-withdrawn animals receiving both ethanol and toluene. Ethanol-toluene exposure increased both relative liver weight and liver triglycerides. Toluene antagonized the hypertriglyceridemia associated with chronic ethanol ingestion. This study indicates that combined ethanol and toluene exposure has minor potential to induce acute liver injury, but results in altered deposition of hepatic triglycerides.

  20. Sensitivity of Trout to Chronic Acute Exposure to Selenium

    Nielsen, Gunnar Gissel; Nielsen, M. Gissel

    1978-01-01

    Trout were exposed to selenite (Na2SeO3) solutions of varying concentrations (0.1-100 ppm Se) for periods of up to 4 wk. A chronic exposure to 0.1 ppm Se or less is non-lethal to trout. Lethality at higher concentrations depends on the length of exposure. Trout that survive for 10 days in tap......-water after contamination will not die as a result of Se toxicity and can safely be used for human consumption....

  1. Does chronic exposure to mobile phones affect cognition?

    Mohan, Mamta; Khaliq, Farah; Panwar, Aprajita; Vaney, Neelam

    2016-01-01

    Mobile phones form an integral part of our modern lifestyle. Following the drastic rise in mobile phone use in recent years, it has become important to study its potential public health impact. Amongst the various mobile phone health hazards, the most alarming is the possible effect on the brain. The aim of the present study was to explore whether chronic exposure to mobile phones affects cognition. Ninety subjects aged 17–25 years with normal hearing were recruited for the study and divided ...

  2. Rapid assessment of accidental exposures (RACE) in environment using ultra-sensitive LiF:Mg,Cu,P (MCP-N) thermoluminescent detectors

    The main goal of this work is to demonstrate a concept and first results of a new system for Rapid Assessment of Accidental Exposures (RACE) which is based on a new generation of ultra sensitive thermoluminescent detectors LiF:Mg, Cu, P. The RACE system is envisaged to be able to monitor environmental radiation doses at a large number of locations within a few days. The RACE will further be able to work as a standard detector system for routine environmental monitoring, but the major innovation is its capability to perform a rapid, short-term (ca. 24-48 hours) in situ dose assessment in case of any type of nuclear accidents, radiocontamination of environment or restoration works. (author). 8 refs, 5 figs

  3. Accidental Innovation

    Austin, Robert D.; Devin, Lee; Sullivan, Erin E.

    2012-01-01

    Historical accounts of human achievement suggest that accidents can play an important role in innovation. In this paper, we seek to contribute to an understanding of how digital systems might support valuable unpredictability in innovation processes by examining how innovators who obtain value from...... they incorporate accidents into their deliberate processes and arranged surroundings. By comparing makers working in varied conditions, we identify specific factors (e.g., technologies, characteristics of technologies) that appear to support accidental innovation. We show that makers in certain specified...... conditions not only remain open to accident but also intentionally design their processes and surroundings to invite and exploit valuable accidents. Based on these findings, we offer advice for the design of digital systems to support innovation processes that can access valuable unpredictability....

  4. Effects in Plant Populations Resulting from Chronic Radiation Exposure

    Geras' kin, Stanislav A.; Volkova, Polina Yu.; Vasiliyev, Denis V.; Dikareva, Nina S.; Oudalova, Alla A. [Russian Institute of Agricultural Radiology and Agroecology, 249032, Obninsk (Russian Federation)

    2014-07-01

    Human industrial activities have left behind a legacy of ecosystems strongly impacted by a wide range of contaminants, including radionuclides. Phyto-toxic effects of acute impact are well known, but the consequences of long-term chronic exposure to low pollutant concentrations is neither well understood nor adequately included in risk assessments. To understand effects of real-world contaminant exposure properly we must pay attention to what is actually going on in the field. However, for many wildlife groups and endpoints, there are no, or very few, studies that link accumulation, chronic exposure and biological effects in natural settings. To fill the gaps, results of field studies carried out on different plant species (winter rye and wheat, spring barley, oats, Scots pine, wild vetch, crested hair-grass) in various radioecological situations (nuclear weapon testing, the Chernobyl accident, uranium and radium processing) to investigate effects of long-term chronic exposure to radionuclides are discussed. Because each impacted site developed in its own way due to a unique history of events, the experience from one case study is rarely directly applicable to another situation. In spite of high heterogeneity in response, we have detected several general patterns. Plant populations growing in areas with relatively low levels of pollution are characterized by the increased level of both cytogenetic alterations and genetic diversity. Accumulation of cellular alterations may afterward influence biological parameters important for populations such as health and reproduction. Presented data provide evidence that in plant populations inhabiting heavily contaminated territories cytogenetic damage were accompanied by decrease in reproductive ability. In less contaminated sites, because of the scarcity of data available, it is impossible to establish exactly the relationship between cytogenetic effects and reproductive ability. Radioactive contamination of the plants

  5. Accidental exposure to biological material in healthcare workers at a university hospital: Evaluation and follow-up of 404 cases.

    Gutierrez, Eliana Battaggia; Lopes, Marta Heloísa; Yasuda, Maria Aparecida Shikanai

    2005-01-01

    The care and follow-up provided to healthcare workers (HCWs) from a large teaching hospital who were exposed to biological material between 1 August 1998 and 31 January 2002 is described here. After exposure, the HCW is evaluated by a nurse and doctor in an emergency consultation and receives follow-up counselling. The collection of 10 ml of blood sample from each HCW and its source patient, when known, is made for immunoenzymatic testing for HIV, HBV and HCV. Evaluation and follow-up of 404 cases revealed that the exposures were concentrated in only a few areas of the hospital; 83% of the HCWs exposed were seen by a doctor responsible for the prophylaxis up to 3 h after exposure. Blood was involved in 76.7% (309) of the exposures. The patient source of the biological material was known in 80.7% (326) of the exposed individuals studied; 80 (24.5%) sources had serological evidence of infection with 1 or more agents: 16.2% were anti-HCV positive, 3.8% were HAgBs positive and 10.9% were anti-HIV positive. 67% (273) of the study population completed the proposed follow-up. No confirmed seroconversion occurred. In conclusion, the observed adherence to the follow-up was quite low, and measures to improve it must be taken. Surprisingly, no difference in adherence to the follow-up was observed among those exposed HCW at risk, i.e. those with an infected or unknown source patient. Analysis of post-exposure management revealed excess prescription of antiretroviral drugs, vaccine and immunoglobulin. Infection by HCV is the most important risk of concern, in our hospital, in accidents with biological material. PMID:15804666

  6. Chronic escalating cocaine exposure, abstinence/withdrawal, and chronic re-exposure: Effects on striatal dopamine and opioid systems in C57BL/6J mice

    Yong ZHANG; Schlussman, Stefan D; Rabkin, Jacqui; Butelman, Eduardo R.; Ho, Ann; Kreek, Mary Jeanne

    2012-01-01

    Cocaine addiction is a chronic relapsing disease with periods of chronic escalating self-exposure, separated by periods of abstinence/withdrawal of varying duration. Few studies compare such cycles in preclinical models. This study models an “addiction-like cycle” in mice to determine neurochemical/molecular alterations that underlie the chronic, relapsing nature of this disease. Groups of male C57BL/6J mice received acute cocaine exposure (14-day saline/14-day withdrawal /13-day saline + 1-d...

  7. Impacts of chronic sublethal exposure to clothianidin on winter honeybees.

    Alkassab, Abdulrahim T; Kirchner, Wolfgang H

    2016-07-01

    A wide application of systemic pesticides and detection of their residues in bee-collected pollen and nectar at sublethal concentrations led to the emergence of concerns about bees' chronic exposure and possible sublethal effects on insect pollinators. Therefore, special attention was given to reducing unintentional intoxications under field conditions. The sensitivity of winter bees throughout their long lifespan to residual exposure of pesticides is not well known, since most previous studies only looked at the effects on summer bees. Here, we performed various laboratory bioassays to assess the effects of clothianidin on the survival and behavior of winter bees. Oral lethal and sublethal doses were administered throughout 12-day. The obtained LD50 values at 48, 72, 96 h and 10 days were 26.9, 18.0, 15.1 and 9.5 ng/bee, respectively. Concentrations <20 µg/kg were found to be sublethal. Oral exposure to sublethal doses was carried out for 12-day and, the behavioral functions were tested on the respective 13th day. Although slight reductions in the responses at the concentrations 10 and 15 µg/kg were observed, all tested sublethal concentrations had showed non-significant effects on the sucrose responsiveness, habitation of the proboscis extension reflex and olfactory learning performance. Nevertheless, chronic exposure to 15 µg/kg affected the specificity of the early long-term memory (24 h). Since the tested concentrations were in the range of field-relevant concentrations, our results strongly suggest that related-effects on winter and summer bees' sensitivity should also be studied under realistic conditions. PMID:27090425

  8. Chronic escalating cocaine exposure, abstinence/withdrawal, and chronic re-exposure: effects on striatal dopamine and opioid systems in C57BL/6J mice.

    Zhang, Yong; Schlussman, Stefan D; Rabkin, Jacqui; Butelman, Eduardo R; Ho, Ann; Kreek, Mary Jeanne

    2013-04-01

    Cocaine addiction is a chronic relapsing disease with periods of chronic escalating self-exposure, separated by periods of abstinence/withdrawal of varying duration. Few studies compare such cycles in preclinical models. This study models an "addiction-like cycle" in mice to determine neurochemical/molecular alterations that underlie the chronic, relapsing nature of this disease. Groups of male C57BL/6J mice received acute cocaine exposure (14-day saline/14-day withdrawal/13-day saline + 1-day cocaine), chronic cocaine exposure (14 day cocaine) or chronic re-exposure (14-day cocaine/14-day withdrawal/14-day cocaine). Escalating-dose binge cocaine (15-30 mg/kg/injection × 3/day, i.p. at hourly intervals) or saline (14-day saline) was administered, modeling initial exposure. In "re-exposure" groups, after a 14-day injection-free period (modeling abstinence/withdrawal), mice that had received cocaine were re-injected with 14-day escalating-dose binge cocaine, whereas controls received saline. Microdialysis was conducted on the 14th day of exposure or re-exposure to determine striatal dopamine content. Messenger RNA levels of preprodynorphin (Pdyn), dopamine D1 (Drd1) and D2 (Drd2) in the caudate putamen were determined by real-time PCR. Basal striatal dopamine levels were lower in mice after 14-day escalating exposure or re-exposure than in those in the acute cocaine group and controls. Pdyn mRNA levels were higher in the cocaine groups than in controls. Long-term adaptation was observed across the stages of this addiction-like cycle, in that the effects of cocaine on dopamine levels were increased after re-exposure compared to exposure. Changes in striatal dopaminergic responses across chronic escalating cocaine exposure and re-exposure are a central feature of the neurobiology of relapsing addictive states. PMID:23164614

  9. Current radiation exposure of man: a comparison between digital imaging and environmental, workplace and accidental radiation burden

    X-ray imaging in diagnostic radiology is recognized worldwide as an outstanding tool for the early recognition and prevention of diseases. The reverse side is that radiography contributes essentially to the exposure of the public. Mean effective doses, averaged over patients and non-patients, are reaching or exceeding the level of natural radiation. This is particularly the case when digital imaging techniques are utilized, such as CT, coronary angiography and interventional radiology. Individual effective doses for a patient may occur between several mSv and several hundred mSv by one examination or a series of examinations, while individual organ doses of a patient may reach equivalent doses even up to several Sv, such as for the skin. The purpose of this review is to provide information on effective dose levels occurring in diagnostic radiology as compared with individual effective doses achieved from environmental radiation, radiation at workplaces and after major radiation incidents. (author)

  10. Rapid assessment of accidental exposures (RACE) with MCP-N (LiF:Mg,Cu,P) detectors

    The system is based on a new generation of ultra-sensitive thermoluminescent dosemeters and is able to monitor environmental radiation doses at a large number of locations within few days and to perform rapid (24 - 48 hours) in situ dose assessment in the event of any nuclear or radiation accident. Technical specifications of the instrumentation and procedures of the system are given. The linearity of the detector response for doses within the range of 1 μGy to 1 Gy is better than 2%. All the detectors investigated demonstrated a good stability in long-term exposure. The detectors are fully comparable with active detectors in short-term and daily routine dose rate measurements. (M.D.)

  11. Review of medical findings in a Marshallese population twenty-six years after accidental exposure to radioactive fallout

    In March 1954, radioactive debris from a thermonuclear weapon test at Bikini Atoll deviated from predicted trajectories and contaminated several atolls in the northern Marshall Islands. As a result, 239 native inhabitants of these islands along with 28 American servicemen and 23 Japanese fishermen received variably severe exposures to diverse ionizing radiations. Fallout material consisted largely of mixed fission products with small amounts of neutron-induced radionuclides and minimal amounts of fissionable elements, producing a complex spectrum of electromagnetic and particulate radiation. Individuals were exposed to deeply penetrating, whole-body gamma irradiation, to internal radiation emitters assimilated either by inhalation or by ingestion of contaminated water and food, and to direct radiation from material accumulating on body surfaces. That accident initiated a cascade of events, medical, social and political, which continue in varying forms to this day. Most of these have been discussed in the open medical literature and in periodic reports issued by the medical team headquartered at Brookhaven National Laboratory. This report attempts to summarize some of the principal findings of medical significnce that have been observed during the subsequent 26 years with particular emphasis on the last six years

  12. Review of medical findings in a Marshallese population twenty-six years after accidental exposure to radioactive fallout

    Conard, R.A.; Paglia, D.E.; Larsen, P.R.

    1980-01-01

    In March 1954, radioactive debris from a thermonuclear weapon test at Bikini Atoll deviated from predicted trajectories and contaminated several atolls in the northern Marshall Islands. As a result, 239 native inhabitants of these islands along with 28 American servicemen and 23 Japanese fishermen received variably severe exposures to diverse ionizing radiations. Fallout material consisted largely of mixed fission products with small amounts of neutron-induced radionuclides and minimal amounts of fissionable elements, producing a complex spectrum of electromagnetic and particulate radiation. Individuals were exposed to deeply penetrating, whole-body gamma irradiation, to internal radiation emitters assimilated either by inhalation or by ingestion of contaminated water and food, and to direct radiation from material accumulating on body surfaces. That accident initiated a cascade of events, medical, social and political, which continue in varying forms to this day. Most of these have been discussed in the open medical literature and in periodic reports issued by the medical team headquartered at Brookhaven National Laboratory. This report attempts to summarize some of the principal findings of medical significnce that have been observed during the subsequent 26 years with particular emphasis on the last six years.

  13. Memory Deficit Recovery after Chronic Vanadium Exposure in Mice

    Oluwabusayo Folarin

    2016-01-01

    Full Text Available Vanadium is a transitional metal with an ability to generate reactive oxygen species in the biological system. This work was designed to assess memory deficits in mice chronically exposed to vanadium. A total of 132 male BALB/c mice (4 weeks old were used for the experiment and were divided into three major groups of vanadium treated, matched controls, and animals exposed to vanadium for three months and thereafter vanadium was withdrawn. Animals were tested using Morris water maze and forelimb grip test at 3, 6, 9, and 12 months of age. The results showed that animals across the groups showed no difference in learning but had significant loss in memory abilities after 3 months of vanadium exposure and this trend continued in all vanadium-exposed groups relative to the controls. Animals exposed to vanadium for three months recovered significantly only 9 months after vanadium withdrawal. There was no significant difference in latency to fall in the forelimb grip test between vanadium-exposed groups and the controls in all age groups. In conclusion, we have shown that chronic administration of vanadium in mice leads to memory deficit which is reversible but only after a long period of vanadium withdrawal.

  14. Chronic obstructive pulmonary disease (COPD and occupational exposures

    Zeni Elena

    2006-06-01

    Full Text Available Abstract Chronic obstructive pulmonary disease (COPD is one of the leading causes of morbidity and mortality in both industrialized and developing countries. Cigarette smoking is the major risk factor for COPD. However, relevant information from the literature published within the last years, either on general population samples or on workplaces, indicate that about 15% of all cases of COPD is work-related. Specific settings and agents are quoted which have been indicated or confirmed as linked to COPD. Coal miners, hard-rock miners, tunnel workers, concrete-manufacturing workers, nonmining industrial workers have been shown to be at highest risk for developing COPD. Further evidence that occupational agents are capable of inducing COPD comes from experimental studies, particularly in animal models. In conclusion, occupational exposure to dusts, chemicals, gases should be considered an established, or supported by good evidence, risk factor for developing COPD. The implications of this substantial occupational contribution to COPD must be considered in research planning, in public policy decision-making, and in clinical practice.

  15. Temperature modulates phototrophic periphyton response to chronic copper exposure.

    Lambert, Anne Sophie; Dabrin, Aymeric; Morin, Soizic; Gahou, Josiane; Foulquier, Arnaud; Coquery, Marina; Pesce, Stéphane

    2016-01-01

    Streams located in vineyard areas are highly prone to metal pollution. In a context of global change, aquatic systems are generally subjected to multi-stress conditions due to multiple chemical and/or physical pressures. Among various environmental factors that modulate the ecological effects of toxicants, special attention should be paid to climate change, which is driving an increase in extreme climate events such as sharp temperature rises. In lotic ecosystems, periphyton ensures key ecological functions such as primary production and nutrient cycling. However, although the effects of metals on microbial communities are relatively well known, there is scant data on possible interactions between temperature increase and metal pollution. Here we led a study to evaluate the influence of temperature on the response of phototrophic periphyton to copper (Cu) exposure. Winter communities, collected in a 8 °C river water, were subjected for six weeks to four thermal conditions in microcosms in presence or not of Cu (nominal concentration of 15 μg L(-1)). At the initial river temperature (8 °C), our results confirmed the chronic impact of Cu on periphyton, both in terms of structure (biomass, distribution of algal groups, diatomic composition) and function (photosynthetic efficiency). At higher temperatures (13, 18 and 23 °C), Cu effects were modulated. Indeed, temperature increase reduced Cu effects on algal biomass, algal class proportions, diatom assemblage composition and photosynthetic efficiency. This reduction of Cu effects on periphyton may be related to lower bioaccumulation of Cu and/or to selection of more Cu-tolerant species at higher temperatures. PMID:26608872

  16. Sub-chronic exposure to second hand smoke induces airspace leukocyte infiltration and decreased lung elastance

    Hartney, John M.; Chu, HongWei; Pelanda, Roberta; Torres, Raul M.

    2012-01-01

    Exposure to second hand tobacco smoke is associated with the development and/or exacerbation of several different pulmonary diseases in humans. To better understand the possible effects of second hand smoke exposure in humans, we sub-chronically (4 weeks) exposed mice to a mixture of mainstream and sidestream tobacco smoke at concentrations similar to second hand smoke exposure in humans. The inflammatory response to smoke exposures was assessed at the end of this time by enumeration of pulmo...

  17. Effects of Chronic Manganese Exposure on Cognitive and Motor Functioning in Non-Human Primates

    Schneider, Jay S.; Decamp, Emmanuel; Koser, Amy Jo; Fritz, Stephanie; Gonczi, Heather; Syversen, Tore; Guilarte, Tomás R.

    2006-01-01

    Acute exposure to manganese is associated with complex behavioral/psychiatric signs that may include Parkinsonian motor features. However, little is known about the behavioral consequences of chronic manganese exposures. In this study, cynomolgus macaque monkeys were exposed to manganese sulfate (10 –15 mg/kg/week) over an exposure period lasting 272 ± 17 days. Prior to manganese exposure, animals were trained to perform tests of cognitive and motor functioning and overall behavior was assess...

  18. Biomarkers for assessing potential carcinogenic effects of chronic arsenic exposure in Inner Mongolia, CHINA

    Arsenic is ubiquitous in the environment. Chronic arsenic exposure via drinking water has been associated. with carcinogenic, cardiovascular, neurological and diabetic effects in humans and has been of great public health concern worldwide. In 2001, U.S. Environmental Protection ...

  19. The Impact of Chronic Pesticide Exposure on Neuropsychological Functioning

    Schultz, Caitlin G.; Ferraro, F. Richard

    2013-01-01

    This study compared neuropsychological test performance of individuals (n = 18) with an occupational history of pesticide exposure to individuals (n = 35) with no such exposure history. Results showed that a history of pesticide-related occupation exposure led to deficits in only Digit Symbol performance. Additionally, the correlation between…

  20. Functional Alterations in the Dorsal Raphe Nucleus Following Acute and Chronic Ethanol Exposure

    Lowery-Gionta, Emily G; Marcinkiewcz, Catherine A.; Kash, Thomas L.

    2014-01-01

    Alcoholism is a pervasive disorder perpetuated in part to relieve negative mood states like anxiety experienced during alcohol withdrawal. Emerging evidence demonstrates a role for the serotonin-rich dorsal raphe (DR) in anxiety following ethanol withdrawal. The current study examined the effects of chronic ethanol vapor exposure on the DR using slice electrophysiology in male DBA2/J mice. We found that chronic ethanol exposure resulted in deficits in social approach indicative of increased a...

  1. Chronic exposure of low dose salinomycin inhibits MSC migration capability in vitro

    Scherzad, Agmal; HACKENBERG, STEPHAN; FROELICH, KATRIN; RAK, KRISTEN; HAGEN, RUDOLF; TAEGER, JOHANNES; BREGENZER, MAXIMILLIAN; KLEINSASSER, NORBERT

    2016-01-01

    Salinomycin is a polyether antiprotozoal antibiotic that is used as a food additive, particularly in poultry farming. By consuming animal products, there may be a chronic human exposure to salinomycin. Salinomycin inhibits the differentiation of preadipocytes into adipocytes. As human mesenchymal stem cells (MSC) may differentiate into different mesenchymal cells, it thus appeared worthwhile to investigate whether chronic salinomycin exposure impairs the functional properties of MSC and induc...

  2. Inflammatory and Remodeling Events in Asthma with Chronic Exposure to House Dust Mites: A Murine Model

    Ahn, Joong Hyun; Kim, Chi Hong; Kim, Yong Hyun; Kim, Seung Joon; Lee, Sook-Young; Kim, Young Kyoon; Kim, Kwan Hyoung; Moon, Hwa Sik; Song, Jeong Sup; Park, Sung Hak; Kwon, Soon Seog

    2007-01-01

    Although animal models with ovalbumin have been used to study chronic asthma, there are difficulties in inducing recurrence as well as in maintaining chronic inflammation in this system. Using a murine model of house dust mite (HDM)-induced bronchial asthma, we examined the airway remodeling process in response to the chronic exposure to HDM. During the seventh and twelfth weeks of study, HDM were inhaled through the nose for three consecutive days and airway responsiveness was measured. Twen...

  3. Effect of Chronic Exposure to Acidic Environment on Radiosensitivity of Gliosarcoma Cells

    Kim, Sora; Kim, Eunhee [Seoul National Univ., Seoul (Korea, Republic of)

    2014-05-15

    In this study, the chronic exposure of cells to acid culture medium, prior or posterior to irradiation, has been investigated for its effect on clonogenic cell survival. Unconventional high-dose radiation therapy, such as SRS, SBRT and MRT, may cause severe vascular damage in tumors, thereby a number of tumor cells facing chronic hypoxia and thus acidosis. According to our observation, gliosarcoma cells become more vulnerable to radiation damage by chronic exposure to acidic condition before irradiation. The longer the preirradiation exposure is, the more vulnerable to radiation damage the cells become. However, the repair of PLD by post-irradiation exposure to acid medium is efficient enough to eliminate the difference in number of the cells carrying PLDs due to different durations of preirradiation exposure to acidic condition.

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

    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.

  5. Protective effects of quercetine on the neuronal injury in frontal cortex after chronic toluene exposure.

    Kanter, Mehmet

    2013-08-01

    The aim of this study was designed to evaluate the possible protective effects of quercetine (QE) on the neuronal injury in the frontal cortex after chronic toluene exposure in rats. The rats were randomly allotted into one of the three experimental groups, namely, groups A (control), B (toluene treated) and C (toluene-treated with QE), where each group contains 10 animals. Control group received 1 ml of normal saline solution, and toluene treatment was performed by the inhalation of 3000 ppm toluene in an 8-h/day and 6-day/week order for 12 weeks. The rats in QE-treated group was given QE (15 mg/kg body weight) once a day intraperitoneally for 12 weeks, starting just after toluene exposure. Tissue samples were obtained for histopathological investigation. To date, no histopathological changes of neurodegeneration in the frontal cortex after chronic toluene exposure in rats by QE treatment have been reported. In this study, the morphology of neurons in the QE treatment group was well protected. Chronic toluene exposure caused severe degenerative changes, shrunken cytoplasm and extensively dark picnotic nuclei in neurons of the frontal cortex. We conclude that QE therapy causes morphologic improvement in neurodegeneration of frontal cortex after chronic toluene exposure in rats. We believe that further preclinical research into the utility of QE may indicate its usefulness as a potential treatment on neurodegeneration after chronic toluene exposure in rats. PMID:22252859

  6. Oral Methylphenidate Alleviates the Fine Motor Dysfunction Caused by Chronic Postnatal Manganese Exposure in Adult Rats

    Beaudin, Stéphane A.; Strupp, Barbara J.; Lasley, Stephen M.; Fornal, Casimir A.; Mandal, Shyamali; Smith, Donald R

    2015-01-01

    Developmental manganese (Mn) exposure is associated with motor dysfunction in children and animal models, but little is known about the underlying neurochemical mechanisms or the potential for amelioration by pharmacotherapy. We investigated whether methylphenidate (MPH) alleviates fine motor dysfunction due to chronic postnatal Mn exposure, and whether Mn exposure impairs brain extracellular dopamine (DA) and norepinephrine (NE) in the prefrontal cortex (PFC) and striatum in adult animals. R...

  7. Sub-chronic exposure to second hand smoke induces airspace leukocyte infiltration and decreases lung elastance

    John M. Hartney

    2012-07-01

    Full Text Available Exposure to second hand tobacco smoke is associated with the development and/or exacerbation of several different pulmonary diseases in humans. To better understand the possible effects of second hand smoke exposure in humans, we sub-chronically (4 weeks exposed mice to a mixture of mainstream and sidestream tobacco smoke at concentrations similar to second hand smoke exposure in humans. The inflammatory response to smoke exposures was assessed at the end of this time by enumeration of pulmonary leukocyte infiltration together with measurements of lung elastance and pathology. This response was measured in both healthy wild type (C57BL/6 mice as well as mouse mutants deficient in the expression of Arhgef1 (Arhgef1–/– that display constitutive pulmonary inflammation and decreased lung elastance reminiscent of emphysema. The results from this study show that sub-chronic second hand smoke exposure leads to significantly increased numbers of airspace leukocytes in both healthy and mutant animals. While sub-chronic cigarette smoke exposure is not sufficient to induce changes in lung architecture as measured by mean linear intercept, both groups exhibit a significant decrease in lung elastance. Together these data demonstrate that even sub-chronic exposure to second hand smoke is sufficient to induce pulmonary inflammation and decrease lung elastance in both healthy and diseased animals and in the absence of tissue destruction.

  8. Modelling the effects of ionizing radiation on survival of animal population: acute versus chronic exposure.

    Kryshev, A I; Sazykina, T G

    2015-03-01

    The objective of the present paper was application of a model, which was originally developed to simulate chronic ionizing radiation effects in a generic isolated population, to the case of acute exposure, and comparison of the dynamic features of radiation effects on the population survival in cases of acute and chronic exposure. Two modes of exposure were considered: acute exposure (2-35 Gy) and chronic lifetime exposure with the same integrated dose. Calculations were made for a generic mice population; however, the model can be applied for other animals with proper selection of parameter values. In case of acute exposure, in the range 2-11 Gy, the population response was in two phases. During a first phase, there was a depletion in population survival; the second phase was a recovery period due to reparation of damage and biosynthesis of new biomass. Model predictions indicate that a generic mice population, living in ideal conditions, has the potential for recovery (within a mouse lifetime period) from acute exposure with dose up to 10-11 Gy, i.e., the population may recover from doses above an LD50 (6.2 Gy). Following acute doses above 14 Gy, however, the mice population went to extinction without recovery. In contrast, under chronic lifetime exposures (500 days), radiation had little effect on population survival up to integrated doses of 14-15 Gy, so the survival of a population subjected to chronic exposure was much better compared with that after an acute exposure with the same dose. Due to the effect of "wasted radiation", the integrated dose of chronic exposure could be about two times higher than acute dose, producing the same effect on survival. It is concluded that the developed generic population model including the repair of radiation damage can be applied both to acute and chronic modes of exposure; results of calculations for generic mice population are in qualitative agreement with published data on radiation effects in mice. PMID

  9. Integrated risk analysis for acute and chronic exposure to toxic chemicals

    Gurjar, B.R.; Mohan, Manju

    2003-10-01

    The traditional practice to assess and evaluate different types of risk in isolation to each other are liable to give erroneous results. Integrated risk assessment is an answer to overcome this problem. This paper presents the cumulative or integrated assessment of acute risk posed by accidental release of hazardous chemical (e.g. chlorine) and chronic risk induced by toxic chemicals (e.g. cadmium, chromium and nickel) present in the ambient environment. The present study has been carried out in a most simplified way to demonstrate and appreciate the broader context of integrated risk analysis (IRA). It has been observed that the inclusion of background risk factors (BRF) in individual risk factors (IRF) related to an industry may significantly alter the siting and planning strategies of that industry.

  10. Impacts of chronic low-level nicotine exposure on Caenorhabditis elegans reproduction: Identification of novel gene targets

    Michael A Smith; Zhang, Yanqiong; Polli, Joseph R.; Wu, Hongmei; Zhang, Baohong; Xiao, Peng; Farwell, Mary A.; Pan, Xiaoping

    2013-01-01

    Effects and mechanisms of chronic exposure to low levels of nicotine is an area fundamentally important however less investigated. We employed the model organism Caenorhabditis elegans to investigate potential impacts of chronic (24 h) and low nicotine exposure (6.17–194.5 μM) on stimulus-response, reproduction, and gene expressions. Nicotine significantly affects the organism's response to touch stimulus (p = 0.031), which follows a dose-dependent pattern. Chronic nicotine exposure promotes ...

  11. 38 CFR 3.316 - Claims based on chronic effects of exposure to mustard gas and Lewisite.

    2010-07-01

    ..., bronchitis, emphysema, asthma or chronic obstructive pulmonary disease. (3) Full-body exposure to nitrogen mustard during active military service together with the subsequent development of acute...

  12. Chronic Nicotine Exposure Attenuates Methamphetamine-Induced Dopaminergic Deficits.

    Vieira-Brock, Paula L; McFadden, Lisa M; Nielsen, Shannon M; Ellis, Jonathan D; Walters, Elliot T; Stout, Kristen A; McIntosh, J Michael; Wilkins, Diana G; Hanson, Glen R; Fleckenstein, Annette E

    2015-12-01

    Repeated methamphetamine (METH) administrations cause persistent dopaminergic deficits resembling aspects of Parkinson's disease. Many METH abusers smoke cigarettes and thus self-administer nicotine; yet few studies have investigated the effects of nicotine on METH-induced dopaminergic deficits. This interaction is of interest because preclinical studies demonstrate that nicotine can be neuroprotective, perhaps owing to effects involving α4β2 and α6β2 nicotinic acetylcholine receptors (nAChRs). This study revealed that oral nicotine exposure beginning in adolescence [postnatal day (PND) 40] through adulthood [PND 96] attenuated METH-induced striatal dopaminergic deficits when METH was administered at PND 89. This protection did not appear to be due to nicotine-induced alterations in METH pharmacokinetics. Short-term (i.e., 21-day) high-dose nicotine exposure also protected when administered from PND 40 to PND 61 (with METH at PND 54), but this protective effect did not persist. Short-term (i.e., 21-day) high-dose nicotine exposure did not protect when administered postadolescence (i.e., beginning at PND 61, with METH at PND 75). However, protection was engendered if the duration of nicotine exposure was extended to 39 days (with METH at PND 93). Autoradiographic analysis revealed that nicotine increased striatal α4β2 expression, as assessed using [(125)I]epibatidine. Both METH and nicotine decreased striatal α6β2 expression, as assessed using [(125)I]α-conotoxin MII. These findings indicate that nicotine protects against METH-induced striatal dopaminergic deficits, perhaps by affecting α4β2 and/or α6β2 expression, and that both age of onset and duration of nicotine exposure affect this protection. PMID:26391161

  13. Particulate matter air pollution exposure: role in the development and exacerbation of chronic obstructive pulmonary disease

    Sean H Ling

    2009-06-01

    Full Text Available Sean H Ling, Stephan F van EedenJames Hogg iCAPTURE Centre for Pulmonary and Cardiovascular Research and Heart and Lung Institute, University of British Columbia, Vancouver, British Columbia, CanadaAbstract: Due to the rapid urbanization of the world population, a better understanding of the detrimental effects of exposure to urban air pollution on chronic lung disease is necessary. Strong epidemiological evidence suggests that exposure to particulate matter (PM air pollution causes exacerbations of pre-existing lung conditions, such as, chronic obstructive pulmonary disease (COPD resulting in increased morbidity and mortality. However, little is known whether a chronic, low-grade exposure to ambient PM can cause the development and progression of COPD. The deposition of PM in the respiratory tract depends predominantly on the size of the particles, with larger particles deposited in the upper and larger airways and smaller particles penetrating deep into the alveolar spaces. Ineffective clearance of this PM from the airways could cause particle retention in lung tissues, resulting in a chronic, low-grade inflammatory response that may be pathogenetically important in both the exacerbation, as well as, the progression of lung disease. This review focuses on the adverse effects of exposure to ambient PM air pollution on the exacerbation, progression, and development of COPD.Keywords: chronic obstructive pulmonary disease, particulate matter, air pollution, alveolar macrophage

  14. Chronic ethanol exposure inhibits distraction osteogenesis in a mouse model: Role of the TNF signaling axis

    Tumor necrosis factor-alpha (TNF-α) is an inflammatory cytokine that modulates osteoblastogenesis. In addition, the demonstrated inhibitory effects of chronic ethanol exposure on direct bone formation in rats are hypothetically mediated by TNF-α signaling. The effects in mice are unreported. Therefore, we hypothesized that in mice (1) administration of a soluble TNF receptor 1 derivative (sTNF-R1) would protect direct bone formation during chronic ethanol exposure, and (2) administration of recombinant mouse TNF-α (rmTNF-α) to ethanol naive mice would inhibit direct bone formation. We utilized a unique model of limb lengthening (distraction osteogenesis, DO) combined with liquid diets to measure chronic ethanol's effects on direct bone formation. Chronic ethanol exposure resulted in increased marrow TNF, IL-1, and CYP 2E1 RNA levels in ethanol-treated vs. control mice, while no significant weight differences were noted. Systemic administration of sTNF-R1 during DO (8.0 mg/kg/2 days) to chronic ethanol-exposed mice resulted in enhanced direct bone formation as measured radiologically and histologically. Systemic rmTNF-α (10 μg/kg/day) administration decreased direct bone formation measures, while no significant weight differences were noted. We conclude that chronic ethanol-associated inhibition of direct bone formation is mediated to a significant extent by the TNF signaling axis in a mouse model

  15. Influence of chronic x-ray exposure on adrenal glucocorticoid function and adrenocorticocyte membrane potential

    The peculiarities of adrenal glucocorticoid function and membrane potential (MP) of zona fasciculata adrenocorticocyte (ACC) in rats after chronic x-ray exposure was studied. The changes of adrenal glucocorticoid function caused by chronic x-ray exposure within a relatively small period of irradiation (1.5 months) are obscure and manifest themselves only at physiological load. With the prolongation of the period (8 and 15 months), more considerable inhibition of the adrenal glucocorticoid function and disturbances in the membrane mechanisms of ACC MP level regulation are revealed

  16. Cytogenetic studies in workers with chronic occupational radiation exposure

    The technique of chromosomal aberration detection on peripheral lymphocytes blood samples from monazite industry workers was used to study the cytogenetic effect of low chronic radiation doses. Cells from 51 workers and 21 controls were analysed. Cytogenetic data from individuals from different working areas were statistically compared among themselves and with the control group. The possible correlations between chromosomal aberration frequencies and cumulative external dose and working time were investigated. The influence of smoking was also tested. The link to the wives spontaneous abortions was analysed. Our results indicate possible biological effects on this sample of workers. (author)

  17. Effects of prenatal exposure to chronic mild stress and toluene in rats

    Hougaard, Karin; Andersen, Maibritt B; Hansen, Ase M;

    2005-01-01

    The aim of the present study was to elucidate whether prenatal chronic stress, in combination with exposure to a developmental neurotoxicant, would increase effects in the offspring compared with the effects of either exposure alone. Development and neurobehavioral effects were investigated in...... female offspring of pregnant rats (Mol:WIST) exposed to chronic mild stress (CMS) during gestational days (GD) 9-20, or 1500 ppm toluene, 6 h/day during gestational days 7-20, or a combination of the two. Prenatal CMS was associated with decreased thymic weight and increased auditory startle response....... The corticosterone response to restraint seemed modified by prenatal exposure to toluene. Lactational body weight was decreased in offsprings subjected to CMS, primarily due to effects in the combined exposure group. Cognitive function was investigated in the Morris water maze, and some indications of...

  18. Radiative accidental matter

    Sierra, D Aristizabal; Wegman, D

    2016-01-01

    Accidental matter models are scenarios where the beyond-the-standard model physics preserves all the standard model accidental and approximate symmetries up to a cutoff scale related with lepton number violation. We study such scenarios assuming that the new physics plays an active role in neutrino mass generation, and show that this unavoidably leads to radiatively induced neutrino masses. We systematically classify all possible models and determine their viability by studying electroweak precision data, big bang nucleosynthesis and electroweak perturbativity, finding that the latter places the most stringent constraints on the mass spectra. These results allow the identification of minimal radiative accidental matter models for which perturbativity is lost at high scales. We calculate radiative charged-lepton flavor violating processes in these setups, and show that $\\mu\\to e \\gamma$ has a rate well within MEG sensitivity provided the lepton-number violating scale is at or below $10^6\\,$ GeV, a value (natur...

  19. Impairment induced by chronic occupational cadmium exposure during brazing process

    Cadmium (CD) is considered a metal of the 20th century to which all inhabitants of develop societies are exposed. Long-term occupational and environmental exposure to CD often results in renal dysfunction as the kidney is considered the critical target organ. The aim of this work was to evalutate both resporatory and renal manifestations induced by occupational exposure to CD compounds during brazing process, and suggesting a protocol for prevention and control for CD- induced health effects. This study was conducted on 20 males occupationally exposed workers. They are divided into two groups: Group-1 included (10) exposed smokers and group-2 included (10) exposed non-smokers. Results of both groups were compared with those of 10 healthy age and sex matched non-smokers. All subjects were subjected to detailed history taking and laboratory investigations including blood and urinary CD, liver profile (SGOT, SGPT and alkline phosphates), kindey function tests (blood urea, creatinine and urinary beta2- microglobulin). The level of Cd in the atmosphere of the work plase air was also assessed to detect the degree of exposure as it was about 6 times greater than thesave level (1 mu /m3).(1) This study demonstrated elevation levels of blood CD, urea, creatinine and urinary CD and beta2 -microglobulin for both exposed worker groups than the controls. In additions no appreciable were noted for liver function tests, although the levels fell within normal range

  20. Chronic obstructive pulmonary disease and long-term exposure to traffic-related air pollution: a cohort study

    Andersen, Zorana J; Hvidberg, Martin; Jensen, Steen S; Ketzel, Matthias; Loft, Steffen; Sørensen, Mette; Tjønneland, Anne; Overvad, Kim; Raaschou-Nielsen, Ole

    2011-01-01

    Short-term exposure to air pollution has been associated with exacerbation of chronic obstructive pulmonary disease (COPD), whereas the role of long-term exposures on the development of COPD is not yet fully understood.......Short-term exposure to air pollution has been associated with exacerbation of chronic obstructive pulmonary disease (COPD), whereas the role of long-term exposures on the development of COPD is not yet fully understood....

  1. Chronic oral exposure to the aldehyde pollutant acrolein induces dilated cardiomyopathy

    Ismahil, Mohamed Ameen; Hamid, Tariq; Haberzettl, Petra; Gu, Yan; Chandrasekar, Bysani; Srivastava, Sanjay; Bhatnagar, Aruni; Prabhu, Sumanth D.

    2011-01-01

    Environmental triggers of dilated cardiomyopathy are poorly understood. Acute exposure to acrolein, a ubiquitous aldehyde pollutant, impairs cardiac function and cardioprotective responses in mice. Here, we tested the hypothesis that chronic oral exposure to acrolein induces inflammation and cardiomyopathy. C57BL/6 mice were gavage-fed acrolein (1 mg/kg) or water (vehicle) daily for 48 days. The dose was chosen based on estimates of human daily unsaturated aldehyde consumption. Compared with ...

  2. Controlled exposure of volunteers with chronic obstructive pulmonary disease to sulfur dioxide

    Linn, W.S.; Fischer, D.A.; Shamoo, D.A.; Spier, C.E.; Valencia, L.M.; Anzar, U.T.; Hackney, J.D.

    1985-08-01

    Twenty-four volunteers with chronic obstructive pulmonary disease (COPD) were exposed to sulfur dioxide (SO/sub 2/) at 0, 0.4, and 0.8 ppm in an environmental control chamber. Exposures lasted 1 hr and included two 15-min exercise periods (mean exercise ventilation rate 18 liter/min). Pulmonary mechanical function was evaluated before exposures, after initial exercise, and at the end of exposure. Blood oxygenation was measured by ear oximetry before exposure and during the second exercise period. Symptoms were recorded throughout exposure periods and for 1 week afterward. No statistically significant changes in physiology or symptoms could be attributed to SO/sub 2/ exposure. Older adults with COPD seem less reactive to a given concentration of SO/sub 2/ than heavily exercising young adult asthmatics. This may be due to lower ventilation rates (i.e., lower SO/sub 2/ dose rates) and/or to lower airway reactivity in the COPD group.

  3. Induction of vascular remodeling in the lung by chronic house dust mite exposure.

    Rydell-Törmänen, Kristina; Johnson, Jill R; Fattouh, Ramzi; Jordana, Manel; Erjefält, Jonas S

    2008-07-01

    Structural changes to the lung are associated with chronic asthma. In addition to alterations to the airway wall, asthma is associated with vascular modifications, although this aspect of remodeling is poorly understood. We sought to evaluate the character and kinetics of vascular remodeling in response to chronic aeroallergen exposure. Because many ovalbumin-driven models used to investigate allergic airway disease do so in the absence of persistent airway inflammation, we used a protocol of chronic respiratory exposure to house dust mite extract (HDME), which has been shown to induce persistent airway inflammation consistent with that seen in humans with asthma. Mice were exposed to HDME intranasally for 7 or 20 consecutive weeks, and resolution of the inflammatory and remodeling response to allergen was investigated 4 weeks after the end of a 7-week exposure protocol. Measures of vascular remodeling, including total collagen deposition, procollagen I production, endothelial and smooth muscle cell proliferation, smooth muscle area, and presence of myofibroblasts, were investigated histologically in lung vessels of different sizes and locations. We observed an increase in total collagen content, which did not resolve upon cessation of allergen exposure. Other parameters were significantly increased after 7 and/or 20 weeks of allergen exposure but returned to baseline after allergen withdrawal. We conclude that respiratory HDME exposure induces airway remodeling and pulmonary vascular remodeling, and, in accordance with airway remodeling, some components of these structural changes may be irreversible. PMID:18314535

  4. Lifetime environmental tobacco smoke exposure and the risk of chronic obstructive pulmonary disease

    Balmes John

    2005-05-01

    Full Text Available Abstract Background Exposure to environmental tobacco smoke (ETS, which contains potent respiratory irritants, may lead to chronic airway inflammation and obstruction. Although ETS exposure appears to cause asthma in children and adults, its role in causing COPD has received limited attention in epidemiologic studies. Methods Using data from a population-based sample of 2,113 U.S. adults aged 55 to 75 years, we examined the association between lifetime ETS exposure and the risk of developing COPD. Participants were recruited from all 48 contiguous U.S. states by random digit dialing. Lifetime ETS exposure was ascertained by structured telephone interview. We used a standard epidemiologic approach to define COPD based on a self-reported physician diagnosis of chronic bronchitis, emphysema, or COPD. Results Higher cumulative lifetime home and work exposure were associated with a greater risk of COPD. The highest quartile of lifetime home ETS exposure was associated with a greater risk of COPD, controlling for age, sex, race, personal smoking history, educational attainment, marital status, and occupational exposure to vapors, gas, dusts, or fumes during the longest held job (OR 1.55; 95% CI 1.09 to 2.21. The highest quartile of lifetime workplace ETS exposure was also related to a greater risk of COPD (OR 1.36; 95% CI 1.002 to 1.84. The population attributable fraction was 11% for the highest quartile of home ETS exposure and 7% for work exposure. Conclusion ETS exposure may be an important cause of COPD. Consequently, public policies aimed at preventing public smoking may reduce the burden of COPD-related death and disability, both by reducing direct smoking and ETS exposure.

  5. Chronic ethanol exposure enhances the aggressiveness of breast cancer: the role of p38γ.

    Xu, Mei; Wang, Siying; Ren, Zhenhua; Frank, Jacqueline A; Yang, Xiuwei H; Zhang, Zhuo; Ke, Zun-Ji; Shi, Xianglin; Luo, Jia

    2016-01-19

    Both epidemiological and experimental studies suggest that ethanol may enhance aggressiveness of breast cancer. We have previously demonstrated that short term exposure to ethanol (12-48 hours) increased migration/invasion in breast cancer cells overexpressing ErbB2, but not in breast cancer cells with low expression of ErbB2, such as MCF7, BT20 and T47D breast cancer cells. In this study, we showed that chronic ethanol exposure transformed breast cancer cells that were not responsive to short term ethanol treatment to a more aggressive phenotype. Chronic ethanol exposure (10 days - 2 months) at 100 (22 mM) or 200 mg/dl (44 mM) caused the scattering of MCF7, BT20 and T47D cell colonies in a 3-dimension culture system. Chronic ethanol exposure also increased colony formation in an anchorage-independent condition and stimulated cell invasion/migration. Chronic ethanol exposure increased cancer stem-like cell (CSC) population by more than 20 folds. Breast cancer cells exposed to ethanol in vitro displayed a much higher growth rate and metastasis in mice. Ethanol selectively activated p38γ MAPK and RhoC but not p38α/β in a concentration-dependent manner. SP-MCF7 cells, a derivative of MCF7 cells which compose mainly CSC expressed high levels of phosphorylated p38γ MAPK. Knocking-down p38γ MAPK blocked ethanol-induced RhoC activation, cell scattering, invasion/migration and ethanol-increased CSC population. Furthermore, knocking-down p38γ MAPK mitigated ethanol-induced tumor growth and metastasis in mice. These results suggest that chronic ethanol exposure can enhance the aggressiveness of breast cancer by activating p38γ MAPK/RhoC pathway. PMID:26655092

  6. Graded exposure for chronic low back pain in older adults : a pilot study

    Leonhardt, Corinna; Kuss, Katrin; Becker, Annette; Basler, Heinz-Dieter; de jong, Jeroen; Flatau, Brigitta; Laekeman, Marjan; Mattenklodt, Peter; Schuler, Matthias; Vlaeyen, Johan; Quint, Sabine

    2016-01-01

    BACKGROUND AND PURPOSE: Fear-avoidance beliefs in older adults with chronic low back pain (CLBP) can lead to disability. Graded exposure-based active physical therapy could be an option to enhance physical ability in older patients with CLBP. The purpose of this study was to develop a standardized g

  7. Lung functions at school age and chronic exposure to outdoor and indoor air pollution

    Neuberger, M.; Kundi, M.; Wiesenberger, W. [Vienna Univ. (Austria). Dept. of Preventive Medicine

    1995-12-31

    Early signs of lung function impairment have been found correlated with annual concentrations of outdoor air pollutants and with passive smoking. To investigate the combined effects of both indicators of chronic exposure to air pollution pulmonary functions in all elementary and high school children of an Austrian town was examined for 5 years. (author)

  8. THERMOREGULATION IN THE RAT DURING CHRONIC, DIETARY EXPOSURE TO CHLORPYRIFOS, AN ORGANOPHOSPHATE INSECTICIDE.

    Administration of chlorpyrifos (CHP) at a dose of 25 to 80 mg/kg (p.o.) To rats results in hypothermia followed by a fever lasting for several days. To understand if chronic, low level exposure to CHP affects thermoregulation in a comparable manner to acute administration, male L...

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

    Hunter, John A.

    2010-01-01

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

  10. SOME EFFECTS OF CHRONIC TRITIUM EXPOSURE DURING SELECTED AGES IN THE RAT

    To assess the implication of age at the time of exposure to chronic irradiation, rats were exposed to constant tritium (HTO) activities of 10 microcuries/ml of body water for 42 days beginning either on the first day of pregnancy or at birth, or at 42 days or 74 days of age. This...

  11. RESPONSES OF SUBJECTS WITH CHRONIC OBSTRUCTIVE PULMONARY DISEASE AFTER EXPOSURES TO 0.3 PPM OZONE

    The authors previously reported (1982) that the respiratory mechanics of intermittently exercising persons with chronic obstructive pulmonary disease (COPD) were unaffected by a 2-h exposure to 0.2 ppm ozone. Employing a single-blind cross-over design protocol, 13 white men with ...

  12. Effects of a Chronic Lower Range of Triclosan Exposure on a Stream Mesocosm Community

    Triclosan (5-chloro-2-(2,4-dichlorophenoxy)phenol) is an antimicrobial found in consumer soaps and toothpaste. It is in treated wastewater effluents at low part per billion concentrations, representing a potentially chronic exposure condition for biota inhabiting receiving strea...

  13. Inequitable Chronic Lead Exposure: A Dual Legacy of Social and Environmental Injustice.

    Leech, Tamara G J; Adams, Elizabeth A; Weathers, Tess D; Staten, Lisa K; Filippelli, Gabriel M

    2016-01-01

    Both historic and contemporary factors contribute to the current unequal distribution of lead in urban environments and the disproportionate impact lead exposure has on the health and well-being of low-income minority communities. We consider the enduring impact of lead through the lens of environmental justice, taking into account well-documented geographic concentrations of lead, legacy sources that produce chronic exposures, and intergenerational transfers of risk. We discuss the most promising type of public health action to address inequitable lead exposure and uptake: primordial prevention efforts that address the most fundamental causes of diseases by intervening in structural and systemic inequalities. PMID:27214670

  14. Optimizing bone surveys performed for suspected non-accidental trauma with attention to maximizing diagnostic yield while minimizing radiation exposure: utility of pelvic and lateral radiographs

    Jha, Priyanka; Stein-Wexler, Rebecca; Seibert, Anthony; Wootton-Gorges, Sandra L. [University of California Davis Medical Center, Department of Radiology, Sacramento, CA (United States); Coulter, Kevin [University of California Davis Medical Center, Department of Pediatrics, Sacramento, CA (United States); Li, Chin-Shang [University of California Davis Medical Center, Division of Biostatistics, Department of Public Health Sciences, Sacramento, CA (United States)

    2013-06-15

    Skeletal surveys for non-accidental trauma (NAT) include lateral spinal and pelvic views, which have a significant radiation dose. To determine whether pelvic and lateral spinal radiographs should routinely be performed during initial bone surveys for suspected NAT. The radiology database was queried for the period May 2005 to May 2011 using CPT codes for skeletal surveys for suspected NAT. Studies performed for skeletal dysplasia and follow-up surveys were excluded. Initial skeletal surveys were reviewed to identify fractures present, including those identified only on lateral spinal and/or pelvic radiographs. Clinical information and MR imaging was reviewed for the single patient with vertebral compression deformities. Of the 530 children, 223 (42.1%) had rib and extremity fractures suspicious for NAT. No fractures were identified solely on pelvic radiographs. Only one child (<0.2%) had vertebral compression deformities identified on a lateral spinal radiograph. This infant had rib and extremity fractures and was clinically paraplegic. MR imaging confirmed the vertebral body fractures. Since no fractures were identified solely on pelvic radiographs and on lateral spinal radiographs in children without evidence of NAT, nor in nearly all with evidence of NAT, inclusion of these views in the initial evaluation of children for suspected NAT may not be warranted. (orig.)

  15. Optimizing bone surveys performed for suspected non-accidental trauma with attention to maximizing diagnostic yield while minimizing radiation exposure: utility of pelvic and lateral radiographs

    Skeletal surveys for non-accidental trauma (NAT) include lateral spinal and pelvic views, which have a significant radiation dose. To determine whether pelvic and lateral spinal radiographs should routinely be performed during initial bone surveys for suspected NAT. The radiology database was queried for the period May 2005 to May 2011 using CPT codes for skeletal surveys for suspected NAT. Studies performed for skeletal dysplasia and follow-up surveys were excluded. Initial skeletal surveys were reviewed to identify fractures present, including those identified only on lateral spinal and/or pelvic radiographs. Clinical information and MR imaging was reviewed for the single patient with vertebral compression deformities. Of the 530 children, 223 (42.1%) had rib and extremity fractures suspicious for NAT. No fractures were identified solely on pelvic radiographs. Only one child (<0.2%) had vertebral compression deformities identified on a lateral spinal radiograph. This infant had rib and extremity fractures and was clinically paraplegic. MR imaging confirmed the vertebral body fractures. Since no fractures were identified solely on pelvic radiographs and on lateral spinal radiographs in children without evidence of NAT, nor in nearly all with evidence of NAT, inclusion of these views in the initial evaluation of children for suspected NAT may not be warranted. (orig.)

  16. No effect of low-level chronic neonicotinoid exposure on bumblebee learning and fecundity.

    Piiroinen, Saija; Botías, Cristina; Nicholls, Elizabeth; Goulson, Dave

    2016-01-01

    In recent years, many pollinators have declined in abundance and diversity worldwide, presenting a potential threat to agricultural productivity, biodiversity and the functioning of natural ecosystems. One of the most debated factors proposed to be contributing to pollinator declines is exposure to pesticides, particularly neonicotinoids, a widely used class of systemic insecticide. Also, newly emerging parasites and diseases, thought to be spread via contact with managed honeybees, may pose threats to other pollinators such as bumblebees. Compared to honeybees, bumblebees could be particularly vulnerable to the effects of stressors due to their smaller and more short-lived colonies. Here, we studied the effect of field-realistic, chronic clothianidin exposure and inoculation with the parasite Nosema ceranae on survival, fecundity, sugar water collection and learning using queenless Bombus terrestris audax microcolonies in the laboratory. Chronic exposure to 1 ppb clothianidin had no significant effects on the traits studied. Interestingly, pesticide exposure in combination with additional stress caused by harnessing bees for Proboscis Extension Response (PER) learning assays, led to an increase in mortality. In contrast to previous findings, the bees did not become infected by N. ceranae after experimental inoculation with the parasite spores, suggesting variability in host resistance or parasite virulence. However, this treatment induced a slight, short-term reduction in sugar water collection, potentially through stimulation of the immune system of the bees. Our results suggest that chronic exposure to 1 ppb clothianidin does not have adverse effects on bumblebee fecundity or learning ability. PMID:27014515

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

    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. PMID:27109494

  18. Inflammation mediators in employees in chronic exposure to neurotoxicants

    Galina Bodienkova

    2014-08-01

    Full Text Available Objectives: The aim of this work is to perform comparative estimation of cytokines levels in chlorinated hydrocarbons and metallic mercury exposure in employees in the dynamics of neurologic disorders formation. Material and Methods: The contents of cytokines IL-1β, IL-2, IL-4, IL-6, TNF-α, INF-γ were determined in blood sera using the method of hardphasic immunoferment analysis. The significance of different average values was assessed using the parametric and non-parametric criteria - Student (in normal distribution and Mann-Whitney tests taking into account the Bonferonni correction (non-difference from normal distribution. Results: It was shown that, a number of inflammation mediators with the dominance, depending on the expositional toxicant and expression of neurological deficiency, take part in the neurointoxication development. Healthy employees show pro-inflammatory responses with different expression degree, which dominate in the immune regulation processes regardless of the expositional factors (metallic mercury vapors and chlorinated hydrocarbons. Conclusions: The production intensity and interconnection between the pro- and anti-inflammatory cytokines may change in the occupational injuries of the nervous system development process. The decrease in the serum concentrations of cytokines along with the increase of clinical manifestation severity may prove dysregulation of the immune system, which promotes maintaining of pathological process and progradient process of neurointoxication. The most obvious is the imbalance of cytokines in the employees exposed to metallic mercury (in all the examined groups that increases neurointoxication in the distant period.

  19. CHRONIC DIETARY EXPOSURE WITH INTERMITTENT SPIKE DOSES OF CHLORPYRIFOS FALLS TO ALTER SOMATOSENSORY EVOKED POTENTIALS, COMPOUND NERVE ACTION POTENTIALS, OR NERVE CONDUCTION VELOCITY IN RATS.

    Human exposure to pesticides is often characterized by chronic low level exposure with intermittent spiked higher exposures. Cholinergic transmission is involved in sensory modulation in the cortex and cerebellum, and therefore may be altered following chlorpyrifos (CPF) exposure...

  20. Bumblebee learning and memory is impaired by chronic exposure to a neonicotinoid pesticide.

    Stanley, Dara A; Smith, Karen E; Raine, Nigel E

    2015-01-01

    Bumblebees are exposed to pesticides applied for crop protection while foraging on treated plants, with increasing evidence suggesting that this sublethal exposure has implications for pollinator declines. The challenges of navigating and learning to manipulate many different flowers underline the critical role learning plays for the foraging success and survival of bees. We assessed the impacts of both acute and chronic exposure to field-realistic levels of a widely applied neonicotinoid insecticide, thiamethoxam, on bumblebee odour learning and memory. Although bees exposed to acute doses showed conditioned responses less frequently than controls, we found no difference in the number of individuals able to learn at field-realistic exposure levels. However, following chronic pesticide exposure, bees exposed to field-realistic levels learnt more slowly and their short-term memory was significantly impaired following exposure to 2.4 ppb pesticide. These results indicate that field-realistic pesticide exposure can have appreciable impacts on learning and memory, with potential implications for essential individual behaviour and colony fitness. PMID:26568480

  1. Heavy metal uranium affects the brain cholinergic system in rat following sub-chronic and chronic exposure

    Uranium is a heavy metal naturally present in the environment that may be chronically ingested by the population. Previous studies have shown that uranium is present in the brain and alters behaviour, notably locomotor activity, sensorimotor ability, sleep/wake cycle and the memory process, but also metabolism of neurotransmitters. The cholinergic system mediates many cognitive systems, including those disturbed after chronic exposure to uranium i.e., spatial memory, sleep/wake cycle and locomotor activity. The objective of this study was to assess whether these disorders follow uranium-induced alteration of the cholinergic system. In comparison with 40 control rats, 40 rats drank 40 mg/L uranyl nitrate for 1.5 or 9 months. Cortex and hippocampus were removed and gene expression and protein level were analysed to determine potential changes in cholinergic receptors and acetylcholine levels. The expression of genes showed various alterations in the two brain areas after short- and long-term exposure. Nevertheless, protein levels of the choline acetyltransferase enzyme (ChAT), the vesicular transporter of acetylcholine (VAChT) and the nicotinic receptor β2 sub-unit (nAChRβ2) were unmodified in all cases of the experiment and muscarinic receptor type 1 (m1AChR) protein level was disturbed only after 9 months of exposure in the cortex (-30%). Acetylcholine levels were unchanged in the hippocampus after 1.5 and 9 months, but were decreased in the cortex after 1.5 months only (-22%). Acetylcholinesterase (AChE) activity was also unchanged in the hippocampus but decreased in the cortex after 1.5 and 9 months (-16% and -18%, respectively). Taken together, these data indicate that the cholinergic system is a target of uranium exposure in a structure-dependent and time-dependent manner. These cholinergic alterations could participate in behavioural impairments.

  2. Chronic Exposure to Ambient Levels of Urban Particles Affects Mouse Lung Development

    Mauad, Thais; Rivero, Dolores Helena Rodriguez Ferreira; de Oliveira, Regiani Carvalho; de Faria Coimbra Lichtenfels, Ana Julia; Guimarães, Eliane Tigre; de Andre, Paulo Afonso; Kasahara, David Itiro; de Siqueira Bueno, Heloisa Maria; Saldiva, Paulo Hilário Nascimento

    2008-01-01

    Rationale: Chronic exposure to air pollution has been associated with adverse effects on children's lung growth. Objectives: We analyzed the effects of chronic exposure to urban levels of particulate matter (PM) on selected phases of mouse lung development. Methods: The exposure occurred in two open-top chambers (filtered and nonfiltered) placed 20 m from a street with heavy traffic in São Paulo, 24 hours/day for 8 months. There was a significant reduction of the levels of PM2.5 inside the filtered chamber (filtered = 2.9 ± 3.0 μg/m3, nonfiltered = 16.8 ± 8.3 μg/m3; P = 0.001). At this exposure site, vehicular sources are the major components of PM2.5 (PM ≤ 2.5μm). Exposure of the parental generation in the two chambers occurred from the 10th to the 120th days of life. After mating and birth of offspring, a crossover of mothers and pups occurred within the chambers, resulting in four groups of pups: nonexposed, prenatal, postnatal, and pre+postnatal. Offspring were killed at the age of 15 (n = 42) and 90 (n = 35) days; lungs were analyzed by morphometry for surface to volume ratio (as an estimator of alveolization). Pressure–volume curves were performed in the older groups, using a 20-ml plethysmograph. Measurements and Main Results: Mice exposed to PM2.5 pre+postnatally presented a smaller surface to volume ratio when compared with nonexposed animals (P = 0.036). The pre+postnatal group presented reduced inspiratory and expiratory volumes at higher levels of transpulmonary pressure (P = 0.001). There were no differences among prenatal and postnatal exposure and nonexposed animals. Conclusions: Our data provide anatomical and functional support to the concept that chronic exposure to urban PM affects lung growth. PMID:18596224

  3. The neurological significance of abnormal natural killer cell activity in chronic toxigenic mold exposures.

    Anyanwu, Ebere; Campbell, Andrew W; Jones, Joseph; Ehiri, John E; Akpan, Akpan I

    2003-11-13

    Toxigenic mold activities produce metabolites that are either broad-spectrum antibiotics or mycotoxins that are cytotoxic. Indoor environmental exposure to these toxigenic molds leads to adverse health conditions with the main outcome measure of frequent neuroimmunologic and behavioral consequences. One of the immune system disorders found in patients presenting with toxigenic mold exposure is an abnormal natural killer cell activity. This paper presents an overview of the neurological significance of abnormal natural killer cell (NKC) activity in chronic toxigenic mold exposure. A comprehensive review of the literature was carried out to evaluate and assess the conditions under which the immune system could be dysfunctionally interfered with leading to abnormal NKC activity and the involvement of mycotoxins in these processes. The functions, mechanism, the factors that influence NKC activities, and the roles of mycotoxins in NKCs were cited wherever necessary. The major presentations are headache, general debilitating pains, nose bleeding, fevers with body temperatures up to 40 degrees C (104 degrees F), cough, memory loss, depression, mood swings, sleep disturbances, anxiety, chronic fatigue, vertigo/dizziness, and in some cases, seizures. Although sleep is commonly considered a restorative process that is important for the proper functioning of the immune system, it could be disturbed by mycotoxins. Most likely, mycotoxins exert some rigorous effects on the circadian rhythmic processes resulting in sleep deprivation to which an acute and transient increase in NKC activity is observed. Depression, psychological stress, tissue injuries, malignancies, carcinogenesis, chronic fatigue syndrome, and experimental allergic encephalomyelitis could be induced at very low physiological concentrations by mycotoxin-induced NKC activity. In the light of this review, it is concluded that chronic exposures to toxigenic mold could lead to abnormal NKC activity with a wide range

  4. The Neurological Significance of Abnormal Natural Killer Cell Activity in Chronic Toxigenic Mold Exposures

    Ebere Anyanwu

    2003-01-01

    Full Text Available Toxigenic mold activities produce metabolites that are either broad-spectrum antibiotics or mycotoxins that are cytotoxic. Indoor environmental exposure to these toxigenic molds leads to adverse health conditions with the main outcome measure of frequent neuroimmunologic and behavioral consequences. One of the immune system disorders found in patients presenting with toxigenic mold exposure is an abnormal natural killer cell activity. This paper presents an overview of the neurological significance of abnormal natural killer cell (NKC activity in chronic toxigenic mold exposure. A comprehensive review of the literature was carried out to evaluate and assess the conditions under which the immune system could be dysfunctionally interfered with leading to abnormal NKC activity and the involvement of mycotoxins in these processes. The functions, mechanism, the factors that influence NKC activities, and the roles of mycotoxins in NKCs were cited wherever necessary. The major presentations are headache, general debilitating pains, nose bleeding, fevers with body temperatures up to 40�C (104�F, cough, memory loss, depression, mood swings, sleep disturbances, anxiety, chronic fatigue, vertigo/dizziness, and in some cases, seizures. Although sleep is commonly considered a restorative process that is important for the proper functioning of the immune system, it could be disturbed by mycotoxins. Most likely, mycotoxins exert some rigorous effects on the circadian rhythmic processes resulting in sleep deprivation to which an acute and transient increase in NKC activity is observed. Depression, psychological stress, tissue injuries, malignancies, carcinogenesis, chronic fatigue syndrome, and experimental allergic encephalomyelitis could be induced at very low physiological concentrations by mycotoxin-induced NKC activity. In the light of this review, it is concluded that chronic exposures to toxigenic mold could lead to abnormal NKC activity with a wide

  5. Comparative sensitivity of three populations of the cladoceran Moinodaphnia macleayi to acute and chronic uranium exposure.

    Semaan, M; Holdway, D A; van Dam, R A

    2001-10-01

    Assessment of differences in the response of three different populations of the tropical cladoceran Moinodaphnia macleayi to uranium exposure was evaluated. The populations tested included a laboratory stock (maintained for 10 years), a wild population collected from Bowerbird Billabong (an uncontaminated environment), and a population collected from Djalkmara Billabong (a relatively contaminated environment with elevated levels of uranium), located on the Ranger uranium mine site, Jabiru East, NT, Australia. Chronic and acute toxicity of uranium was determined for all three populations. The no-observed-effect-concentration (NOEC; reproduction) and lowest observed-effect-concentration (LOEC; reproduction) for uranium ranged between 8-31 micrograms L-1 and 20-49 micrograms L-1, respectively, for all three populations. The 48 h EC50 (immobilization-lethality) for uranium ranged between 160-390 micrograms L-1 for all three populations. There was little difference in the response of the three populations of M. macleayi to acute and chronic uranium exposure, although the response of the laboratory population to chronic uranium exposure appeared more variable than the "wild" populations. There was no apparent tolerance in the population of M. macleayi obtained from Djalkmara Billabong when exposed to elevated levels of uranium. M. macleayi was significantly more sensitive to uranium exposure than other species previously tested. It was concluded that the sensitivity of the laboratory population (to uranium) is still representative of natural M. macleayi populations. PMID:11594022

  6. A safe strategy to decrease fetal lead exposure in a woman with chronic intoxication.

    Leiba, Adi; Hu, Howard; Zheng, Amin; Kales, Stefanos N

    2010-08-01

    During pregnancy skeletal lead is mobilized by maternal bone turnover and can threaten fetal development. The exact strategy suggested to women of childbearing age, who were chronically exposed to lead, and, thus, have high bone lead burden, is not well established. We describe 4 years of follow-up of a 29-year-old woman with chronic lead intoxication. We (a) advised her to delay conception until 'toxicological clearance', (b) treated her with multiple courses of lead chelator, DMSA, and (c) prescribed oral calcium. Patient had low blood lead and protoporphyrin level during pregnancy until delivery. Delaying conception, lead chelation, and calcium supplementation can decrease fetal exposure. PMID:20459344

  7. Reaction of fresh water zooplankton community to chronic radiation exposure

    Osipov, D.; Pryakhin, E. [Urals Research Center for Radiation Medicine - URCRM (Russian Federation); Ivanov, I. [FSUE Mayak PA (Russian Federation)

    2014-07-01

    The characteristic features of ecological community as a whole and cenosis of zooplankton organisms as part of it determine the intensity of the processes of self-purification of water and the formation of a particular body of water. Identifying features of the structure and composition of the zooplankton community of aquatic ecosystems exposed to different levels of radiation exposure, it is necessary to identify patterns of changes in zooplankton and hydro-biocenosis as a whole. Industrial reservoirs, the storage of liquid low-level radioactive waste 'Mayak' for decades, have high radiation load. A large range of levels of radioactive contamination (total volume beta-activity in water varies from 2.2x10{sup 3} to 2.3x10{sup 7} Bq/l, total volume alpha-activity - from 2.6x10{sup -1} to 3.1x10{sup 3} Bq/l) provides a unique opportunity to study ecosystems in a number of reservoirs with increasing impact of radiation factor. We studied five reservoirs that were used as the storage of low-and intermediate-level liquid radioactive waste pond and one comparison water body. In parallel with zooplankton sampling water samples were collected for hydro-chemical analysis. 41 indicators were analysed in order to assess the water chemistry. To determine the content of radionuclides in the various components of the ecosystem samples were collected from water, bottom sediments and plankton. Sampling of zooplankton for the quantitative analysis was performed using the method of weighted average auto bathometer. Apshteyn's plankton net of the surface horizon was used for qualitative analysis of the species composition of zooplankton. Software package ERICA Assessment Tool 2012 was used for the calculation of the absorbed dose rate. Species diversity and biomass of zooplankton, the share of rotifers in the number of species, abundance and biomass decrease with the increase of the absorbed dose rate and salinity. The number of species in a sample decreases with the

  8. Radiative accidental matter

    Sierra, D. Aristizabal; Simoes, C.; Wegman, D.

    2016-07-01

    Accidental matter models are scenarios where the beyond-the-standard model physics preserves all the standard model accidental and approximate symmetries up to a cutoff scale related with lepton number violation. We study such scenarios assuming that the new physics plays an active role in neutrino mass generation, and show that this unavoidably leads to radiatively induced neutrino masses. We systematically classify all possible models and determine their viability by studying electroweak precision data, big bang nucleosynthesis and electroweak perturbativity, finding that the latter places the most stringent constraints on the mass spectra. These results allow the identification of minimal radiative accidental matter models for which perturbativity is lost at high scales. We calculate radiative charged-lepton flavor violating processes in these setups, and show that μ → eγ has a rate well within MEG sensitivity provided the lepton-number violating scale is at or below 5×105 GeV, a value (naturally) assured by the radiative suppression mechanism. Sizeable τ → μγ branching fractions within SuperKEKB sensitivity are possible for lower lepton-number breaking scales. We thus point out that these scenarios can be tested not only in direct searches but also in lepton flavor-violating experiments.

  9. Low-level chronic exposure to tritium: An improved basis for hazard evaluation

    The possibility that significant biological effects may result from chronic low-level exposure to 3HOH is the main health and environmental concern regarding tritium from nuclear energy operations. Direct data for such exposure are, however, largely still unavailable. Information on chronic irradiation at low levels derives mostly from γ-ray studies, so extrapolations are necesary for tritium. But controversy exists on tritium's relative biological effectiveness (RBE) compared to γ radiation and on the related quality factor (Q) used for radiation protection (recently adjusted downward from 1.7 to 1). A firmer basis for extrapolation is needed. The author has obtained quantitative data for low-level 3HOH and 60Co γ-ray exposures in the intact mammal. Developing mice were exposed to various doses over 33 days; surviving oocytes were then counted in ovaries and compared with controls, providing dose-response curves for both radiations. By comparing these curves, RBE values were determined. The RBE was found to vary inversely with dose, in accord with the theory of dual radiation action. At γ-ray doses of 50 rads, the RBE was 1.6. It increased at lower doses, reaching a value of approximately 3. With short exposures, the RBE was lower, due possibly to differences in microdistribution of 3H. These results demonstrate that conclusions from both high-dose and short-term experiments are likely to underestimate the effects of low-level chronic exposure to 3HOH. Measurement of the systematic variation of tritium's RBE with dose and recognition of the effect of exposure duration provide a more secure basis for hazard evaluation. (author)

  10. Mitochondrial energy metabolism impairment and liver dysfunction following chronic exposure to dichlorvos

    Although the effects of acute pesticide poisoning are well known but, hardly any data exists regarding the health effects after long-term low-level exposure. Major unresolved issues include the effect of moderate exposure in the absence of poisoning. The present study elucidates a possible mechanism by which chronic organophosphate exposure (dichlorvos 6 mg/kg b.wt., s.c. for 12 weeks) causes liver dysfunction. Mitochondria, a primary site of cellular energy generation and oxygen consumption represent a likely target for organophosphate poisoning. Therefore, the objective of the current study was planned with an aim to investigate the effect of chronic dichlorvos exposure on liver mitochondrial electron transport chain (ETC), mitochondrial calcium uptake and its implications on the induction of liver enzymes and liver dysfunction in rodent model. Our results indicated decreased mitochondrial electron transfer activities of cytochrome oxidase along with altered mitochondrial complexes I and II activity. This decrease in the activities of electron transport complexes in turn affected the ATP synthesis and ATP levels adversely in the mitochondria isolated from dichlorvos (DDVP) treated rat liver. Mitochondrial preparation from DDVP treated rat liver demonstrated significant increase in mitochondrial Ca2+ uptake and increase ROS levels. The alterations in the mitochondrial calcium uptake, mitochondrial electron transfer enzyme activities and increase ROS levels in turn might have caused an increase in liver enzymes (ALT, AST and ALP). The electron micrographs of liver cells depicted morphological changes in mitochondria as well as nucleus following 12 weeks of exposure to DDVP. These studies provide an evidence of impaired mitochondrial bioenergetics which may lead to liver dysfunction after chronic exposure to dichlorvos.

  11. Chronic exposure of juvenile rats to environmental noise impairs hippocampal cell proliferation in adulthood

    Fernando Jáuregui-Huerta

    2011-01-01

    Full Text Available Increasing evidence indicates that chronic exposure to environmental noise may permanently affect the central nervous system. The aim of this study was to evaluate the long-term effects of early exposure to environmental noise on the hippocampal cell proliferation of the adult male rat. Early-weaned Wistar rats were exposed for 15 days to a rats′ audiogram-fitted adaptation to a noisy environment. Two months later, the rats were injected with the cellular proliferation marker 5΄bromodeoxiuridine (BrdU, and their brains were processed for immunohistochemical analysis. Coronal sections were immunolabeled with anti-BrdU antibodies to identify new-born cells in dentate gyrus (DG, cornu amonis areas CA1 and CA3. In addition, blood samples were obtained to evaluate corticosterone serum levels after noise exposure. All data are expressed as mean΁standard deviation. For mean comparisons between groups, we used the Student t test. We found an increase in corticosterone serum levels after environmental noise exposure. Interestingly, noise-exposed rats showed a long-term reduction of proliferating cells in the hippocampal formation, as compared to controls. These findings indicate that chronic environmental noise exposure at young ages produces persistent non-auditory impairment that modifies cell proliferation in the hippocampal formation.

  12. Environmental Heavy Metal Exposure and Chronic Kidney Disease in the General Population

    Kim, Nam Hee; Hyun, Young Youl; Lee, Kyu-Beck; Chang, Yoosoo; Rhu, Seungho; Oh, Kook-Hwan; Ahn, Curie

    2015-01-01

    Lead (Pb), mercury (Hg), and cadmium (Cd) are common heavy metal toxins and cause toxicological renal effects at high levels, but the relevance of low-level environmental exposures in the general population is controversial. A total of 1,797 adults who participated in the KNHANES (a cross-sectional nationally representative survey in Korea) were examined, and 128 of them (7.1%) had chronic kidney disease (CKD). Our study assessed the association between Pb, Hg, Cd exposure, and CKD. Blood Pb ...

  13. Research progress in study of accidental hypothermia

    Yuan, Rui; Zhang, Zhi-cheng

    2016-01-01

    Accidental hypothermia refers to a state of lowering of core body temperature down to 35 ℃induced by drowning, burial in snow and prolonged exposure to cold environment, etc. Hypothermia may affect the cardiovascular system, respiratory system, digestive system, etc. The triad consisting "hypothermia, acidosis and coagulopathy" is an important factor accelerating the death of patients. Early, timely application of rewarming measures is regarded as the basic principle in treatment of hypotherm...

  14. Chronic disease and early exposure to air-borne mixtures. 2. Exposure assessment.

    Argo, James

    2007-10-15

    This work is part of a larger study of the impact of early exposure to releases from industry on the etiology of cancer. Releases from all kraft and sulfite mills, coke ovens, oil refineries, copper, nickel, and lead/zinc smelters operating in Canada during the exposure period of 1967-1970 have been determined. All plumes have been expressed in microg BaP eq/d using the RASH methodology. The releases have been divided into process, boiler fuel, dioxin, and SO2 emissions. Combustion sources have been defined with FIREv6.23. Dioxin congenors are expected in all source types when the boiler fuel is heavy fuel oil, wood or wood bark, or coal. All approximately 90 communities examined have an inverted sex ratio. PMID:17993167

  15. Chronic caffeine or theophylline exposure reduces gamma-aminobutyric acid/benzodiazepine receptor site interactions.

    Roca, D J; Schiller, G D; Farb, D H

    1988-05-01

    Methylxanthines, such as caffeine and theophylline, are adenosine receptor antagonists that exert dramatic effects upon the behavior of vertebrate animals by increasing attentiveness, anxiety, and convulsive activity. Benzodiazepines, such as flunitrazepam, generally exert behavioral effects that are opposite to those of methylxanthines. We report the finding that chronic exposure of embryonic brain neurons to caffeine or theophylline reduces the ability of gamma-aminobutyric acid (GABA) to potentiate the binding of [3H]flunitrazepam to the GABA/benzodiazepine receptor. This theophylline-induced "uncoupling" of GABA- and benzodiazepine-binding site allosteric interactions is blocked by chloroadenosine, an adenosine receptor agonist, indicating that the chronic effects of theophylline are mediated by a site that resembles an adenosine receptor. We speculate that adverse central nervous system effects of long-term exposure to methylxanthines such as in caffeine-containing beverages or theophylline-containing medications may be exerted by a cell-mediated modification of the GABAA receptor. PMID:2835648

  16. Chronic ethanol exposure produces tolerance to elevations in neuroactive steroids: Mechanisms and reversal by exogenous ACTH

    Boyd, Kevin N.; Kumar, Sandeep; O'Buckley, Todd K.; Morrow, A. Leslie

    2010-01-01

    Acute ethanol administration increases potent GABAergic neuroactive steroids, specifically (3α,5α)-3-hydroxypregnan-20-one (3α,5α-THP) and (3α,5α)-3,21-dihydroxypregnan-20-one. In addition, neuroactive steroids contribute to ethanol actions. Chronic ethanol exposure results in tolerance to many effects of ethanol, including ethanol-induced increases in neuroactive steroid levels. To determine the mechanisms of tolerance to ethanol-induced increases in neuroactive steroids, we investigated cri...

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

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

    2015-01-01

    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.

  18. The Consequences of adolescent chronic unpredictable stress exposure on brain and behavior

    Hollis, Fiona; Isgor, Ceylan; Kabbaj, Mohamed

    2013-01-01

    There is increasing evidence for adolescence as a time period vulnerable to environmental perturbations such as stress. What is unclear is the persistent nature of the effects of stress and how specific these effects are to the type of stressor. In this review, we describe the effects of chronic, unpredictable stress (CUS) exposure during adolescence on adult behavior and brain morphology and function in animal models. We provide evidence for adolescence as a critical window for the effects o...

  19. Chronic estradiol exposure induces oxidative stress in the hypothalamus to decrease hypothalamic dopamine and cause hyperprolactinemia

    MohanKumar, Sheba M.J.; Kasturi, Badrinarayanan S.; Shin, Andrew C.; Balasubramanian, Priya; Gilbreath, Ebony T.; Subramanian, Madhan; MohanKumar, Puliyur S

    2010-01-01

    Estrogens are known to cause hyperprolactinemia, most probably by acting on the tuberoinfundibular dopaminergic (TIDA) system of the hypothalamus. Dopamine (DA) produced by TIDA neurons directly inhibits prolactin secretion and, therefore, to stimulate prolactin secretion, estrogens inhibit TIDA neurons to decrease DA production. However, the mechanism by which estrogen produces this effect is not clear. In the present study, we used a paradigm involving chronic exposure to low levels of estr...

  20. Pulmonary function and exercise-associated changes with chronic low-level paraquat exposure

    Schenker, M B; Stoecklin, Maria T; Lee, Kiyoung; Lupercio, Rafael; Zeballos, R. Jorge; Enright, Paul; Hennessy, Tamara E.; Laurel A. Beckett

    2004-01-01

    The present study was undertaken to test the hypothesis that chronic, low-level paraquat exposure causes restrictive lung function with gas transfer impairment. Three hundred thirty-eight Costa Rican farm workers from banana, coffee and palm oil farms completed a questionnaire, spirometry and single-breath carbon monoxide diffusing capacity. Subjects 40 years of age or older, without other medical risk factors, completed maximal cardiopulmonary exercise tests. Most (66.6%) were paraquat hand...

  1. Biochemical Impedance on Intracellular Functions of Vitamin B12 in Chronic Toxigenic Mold Exposures

    Ebere C. Anyanwu; Ijeoma Kanu

    2007-01-01

    A majority of patients with neurological disorders with chronic exposures to toxigenic molds and mycotoxins has vitamin B12 deficiency that is unrelated to dietary insufficiency. Vitamin B12 is a source of coenzymes, and participates in intracellular recycling of methionine, and in methionine synthase reactions. The biochemical processes that lead to B12 depletion and deficiency are not fully understood. This paper examines and assesses various most likely biochemical reasons that could imped...

  2. Comparative transcriptomic responses to chronic cadmium, fluoranthene, and atrazine exposure in Lumbricus rubellus.

    Svendsen, C; Owen, J; Kille, P; Wren, J; Jonker, M J; Headley, B A; Morgan, A J; Blaxter, M; Stürzenbaum, S R; Hankard, P K; Lister, L J; Spurgeon, D J

    2008-06-01

    Transcriptional responses of a soil-dwelling organism (the earthworm Lumbricus rubellus) to three chemicals, cadmium (Cd), fluoranthene (FA), and atrazine (AZ), were measured following chronic exposure, with the aim of identifying the nature of any shared transcriptional response. Principal component analysis indicated full or partial separation of control and exposed samples for each compound but not for the composite set of all control and exposed samples. Partial least-squares discriminant analysis allowed separation of the control and exposed samples for each chemical and also for the composite data set, suggesting a common transcriptional response to exposure. Genes identified as changing in expression level (by the least stringent test for significance) following exposure to two chemicals indicated a substantial number of common genes (> 127). The three compound overlapping gene set, however, comprised only 25 genes. We suggest that the low commonality in transcriptional response may be linked to the chronic concentrations (approximately 10% EC50) and chronic duration (28 days) used. Annotations of the three compound overlapping gene set indicated that genes from pathways most often associated with responses to environmental stress, such as heat shock, phase I and II metabolism, antioxidant defense, and cation balance, were not represented. The strongest annotation signature was for genes important in mitochondrial function and energy metabolism. PMID:18589989

  3. Estimation of the radiation exposure resulting from accidental discharges of radionuclides from nuclear facilities into rivers considering the time dependency on relevant parameters

    This report deals with possible source terms as well as with the transport of radionuclides in rivers. An estimate is presented of the radionuclide concentrations of Sr-90 and Cs-137 in the river system due to supposed or estimated short- and long-term source terms. The results are described of validating calculations for determination of the concentrations of Co-60 in the suspended load and sediment media. Then the radiation exposure resulting from the various source terms as well as selected results are discussed. (orig.)

  4. Age influence on mice lung tissue response to [i]Aspergillus fumigatus[/i] chronic exposure

    Marta Kinga Lemieszek

    2015-02-01

    Full Text Available [b]Introduction and objective[/b]. Exposure to conidia of [i]Aspergillus fumigatus[/i] was described as a causative factor of a number of the respiratory system diseases, including asthma, chronic eosinophilic pneumonia, hypersensitivity pneumonitis and bronchopulmonary aspergillosis. The study investigates the effects of the repeated exposure to [i]A. fumigatus[/i] in mice pulmonary compartment. Our work tackles two, so far insufficiently addressed, important aspects of interaction between affected organism and[i] A. fumigatus[/i]: 1 recurrent character of exposure (characteristic for pathomechanism of the abovementioned disease states and 2 impact of aging, potentially important for the differentiation response to an antigen. [b]Materials and methods[/b]. In order to dissect alterations of the immune system involved with both aging and chronic exposure to [i]A. fumigatus[/i], we used 3- and 18-month-old C57BL/6J mice exposed to repeated[i] A. fumigatus[/i] inhalations for 7 and 28 days. Changes in lung tissue were monitored by histological and biochemical evaluation. Concentration of pro- and anti-inflammatory cytokines in lung homogenates was assessed by ELISA tests. [b]Results and conclusions. [/b]Our study demonstrated that chronic inflammation in pulmonary compartment, characterized by the significant increase of proinflammatory cytokines (IL1, IL6, IL10 levels, was the dominant feature of mice response to repeated [i]A. fumigatus[/i] inhalations. The pattern of cytokines’ profile in the course of exposure was similar in both age groups, however in old mice the growth of the cytokines’ levels was more pronounced (especially in case of IL1.

  5. Role of oxidative stress in liver and kidney in uranium toxicity after chronic exposure

    Uranium is a radioactive heavy metal found in the environment. Due to its natural presence and to civil and militaries activities, general population can be exposed to U throughout drinking water or contaminated food. The pro/anti-oxidative system is a defense system which is often implicated in case of acute exposure to U. The aim of this thesis is to study the role of the pro/anti-oxidative system after chronic exposure to U in the liver and the kidney. After chronic exposure of rats to different U concentrations, this radionuclide accumulated in the organs in proportion to U intake; until 6 μg.g-1 of kidney tissues. U is localized in nucleus of the proximal tubular cells of the kidney. No nephrotoxicity was described even for the higher U level in drinking water and a reinforcement of the pro/anti-oxidative system with an increase in glutathione is observed. The study of U internal contamination in Nrf2 deficient mice, a cytoprotective transcription factor involved in the anti-oxidative defense has been realized. U accumulate more in Nrf2 mice than in WT mice but the biologic effects of U on the pro/anti-oxidative system did not seem to implicate Nrf2. At the cell level, a correlation between U distribution in HepG2 cells and the biological effects on this system is observed after U exposure at low concentrations. Soluble distribution of U is observed in cell nucleus. The apparition of U precipitates is correlated to the establishment of the adaptive mechanisms overtime which are overwhelmed and lead to a cellular toxicity at higher U level. In conclusion, these results suggest that the reinforcement of pro/anti-oxidative system could be an adaptive mechanism after chronic exposure at low U concentration. (author)

  6. Does chronic occupational exposure to volatile anesthetic agents influence the rate of neutrophil apoptosis?

    Goto, Y

    2012-02-03

    PURPOSE: The purpose of this preliminary investigation was to determine whether the rate of neutrophil apoptosis in health care workers is influenced by exposure to volatile anesthetic agents. METHODS: Percentage neutrophil apoptosis (Annexin-V FITC assay) was measured in health care workers (n = 20) and unexposed volunteers (n = 10). For the health care workers, time weighted personal exposure monitoring to N2O, sevoflurane and isoflurane was carried out. RESULTS: The sevoflurane and isoflurane concentrations to which health care workers were exposed were less than recommended levels in all 20 cases. Percent apoptosis was less at 24 (but not at one and 12) hr culture in health care workers [50.5 (9.7)%; P = 0.008] than in unexposed volunteers [57.3 (5.1)%]. CONCLUSION: Inhibition of neutrophil apoptosis at 24 hr culture was demonstrated in health care workers chronically exposed to volatile anesthetic agents. Exposure was well below recommended levels in the both scavenged and unscavenged work areas in which the study was carried out. Further study is required to assess the effect of greater degrees of chronic exposure to volatile anesthetic agents on neutrophil apoptosis.

  7. TBBPA chronic exposure produces sex-specific neurobehavioral and social interaction changes in adult zebrafish.

    Chen, Jiangfei; Tanguay, Robert L; Simonich, Michael; Nie, Shangfei; Zhao, Yuxin; Li, Lelin; Bai, Chenglian; Dong, Qiaoxiang; Huang, Changjiang; Lin, Kuangfei

    2016-01-01

    The toxicity of tetrabromobisphenol A (TBBPA) has been extensively studied because of its high production volume. TBBPA is toxic to aquatic fish based on acute high concentration exposure tests, and few studies have assessed the behavioral effects of low concentration chronic TBBPA exposures in aquatic organisms. The present study defined the developmental and neurobehavioral effects associated with exposure of zebrafish to 0, 5 and 50nM TBBPA during 1-120days post-fertilization (dpf) following by detoxification for four months before the behaviors assessment. These low concentration TBBPA exposures were not associated with malformations and did not alter sex ratio, but resulted in reduced zebrafish body weight and length. Adult behavioral assays indicated that TBBPA exposed males had significantly higher average swim speeds and spent significantly more time in high speed darting mode and less time in medium cruising mode compared to control males. In an adult photomotor response assay, TBBPA exposure was associated with hyperactivity in male fish. Female zebrafish responses in these assays followed a similar trend, but the magnitude of TBBPA effects was generally smaller than in males. Social interaction evaluated using a mirror attack test showed that 50nM TBBPA exposed males had heightened aggression. Females exposed to 50nM TBBPA spent more time in the vicinity of the mirror, but did not show increased aggression toward the mirror compared to unexposed control fish. Overall, the hyperactivity and social behavior deficits ascribed here to chronic TBBPA exposure was most profound in males. Our findings indicate that TBBPA can cause developmental and neurobehavioral deficits, and may pose significant health risk to humans. PMID:27221227

  8. Chronic caffeine exposure attenuates blast-induced memory deficit in mice

    Ya-Lei Ning; Nan Yang; Xing Chen; Zi-Ai Zhao; Xiu-Zhu Zhang; Xing-Yun Chen; Ping Li

    2015-01-01

    Objective:To investigate the effects of three different ways of chronic caffeine administration on blastinduced memory dysfunction and to explore the underlying mechanisms.Methods:Adult male C57BL/6 mice were used and randomly divided into five groups:control:without blast exposure,con-water:administrated with water continuously before and after blast-induced traumatic brain injury (bTBI),con-caffeine:administrated with caffeine continuously for 1 month before and after bTBI,pre-caffeine:chronically administrated with caffeine for 1 month before bTBI and withdrawal after bTBI,post-caffeine:chronically administrated with caffeine after bTBI.After being subjected to moderate intensity of blast injury,mice were recorded for learning and memory performance using Morris water maze (MWM) paradigms at 1,4,and 8 weeks post-blast injury.Neurological deficit scoring,glutamate concentration,proinflammatory cytokines production,and neuropathological changes at 24 h,1,4,and 8 weeks post-bTBI were examined to evaluate the brain injury in early and prolonged stages.Adenosine A1 receptor expression was detected using qPCR.Results:All of the three ways of chronic caffeine exposure ameliorated blast-induced memory deficit,which is correlated with the neuroprotective effects against excitotoxicity,inflammation,astrogliosis and neuronal loss at different stages of injury.Continuous caffeine treatment played positive roles in both early and prolonged stages of bTBI;pre-bTBl and post-bTBl treatment of caffeine tended to exert neuroprotective effects at early and prolonged stages of bTBI respectively.Up-regulation of adenosine A1 receptor expression might contribute to the favorable effects of chronic caffeine consumption.Conclusion:Since caffeinated beverages are widely consumed in both civilian and military personnel and are convenient to get,the results may provide a promising prophylactic strategy for blast-induced neurotrauma and the consequent cognitive impairment.

  9. Association between pre- and perinatal exposures and Tourette syndrome or chronic tic disorder in the ALSPAC cohort†

    Mathews, Carol A; Scharf, Jeremiah M.; Miller, Laura L; Macdonald-Wallis, Corrie; Lawlor, Debbie A.; Ben-Shlomo, Yoav

    2014-01-01

    Background Tourette syndrome and chronic tic disorder are heritable but aetiologically complex. Although environment plays a role in their development, existing studies of non-genetic risk factors are inconsistent. Aims To examine the association between pre- and perinatal exposures and Tourette syndrome/chronic tic disorder in the Avon Longitudinal Study of Parents and Children (ALSPAC) prospective longitudinal pre-birth cohort. Method Relationships between exposures and Tourette syndrome/ch...

  10. The effect of chronic exposure to highly aggressive mice on hippocampal gene expression of non-aggressive subordinates

    Feldker, DEM; Morsink, MC; Veenema, AH; Datson, NA; Proutski, [No Value; Lathouwers, D; de Kloet, ER; Vreugdenhil, E

    2006-01-01

    Exposure to a chronic psychosocial stressor changes the behavioral and neuroendocrine response pattern and causes structural changes in the rodent hippocampus. However, the underlying molecular mechanism of these changes induced by chronic stress is largely unknown. Recently, it was shown that expos

  11. Chronic cadmium exposure in vitro induces cancer cell characteristics in human lung cells

    Person, Rachel J.; Tokar, Erik J.; Xu, Yuanyuan; Orihuela, Ruben; Ngalame, Ntube N. Olive; Waalkes, Michael P., E-mail: waalkes@niehs.nih.gov

    2013-12-01

    Cadmium is a known human lung carcinogen. Here, we attempt to develop an in vitro model of cadmium-induced human lung carcinogenesis by chronically exposing the peripheral lung epithelia cell line, HPL-1D, to a low level of cadmium. Cells were chronically exposed to 5 μM cadmium, a noncytotoxic level, and monitored for acquired cancer characteristics. By 20 weeks of continuous cadmium exposure, these chronic cadmium treated lung (CCT-LC) cells showed marked increases in secreted MMP-2 activity (3.5-fold), invasion (3.4-fold), and colony formation in soft agar (2-fold). CCT-LC cells were hyperproliferative, grew well in serum-free media, and overexpressed cyclin D1. The CCT-LC cells also showed decreased expression of the tumor suppressor genes p16 and SLC38A3 at the protein levels. Also consistent with an acquired cancer cell phenotype, CCT-LC cells showed increased expression of the oncoproteins K-RAS and N-RAS as well as the epithelial-to-mesenchymal transition marker protein Vimentin. Metallothionein (MT) expression is increased by cadmium, and is typically overexpressed in human lung cancers. The major MT isoforms, MT-1A and MT-2A were elevated in CCT-LC cells. Oxidant adaptive response genes HO-1 and HIF-1A were also activated in CCT-LC cells. Expression of the metal transport genes ZNT-1, ZNT-5, and ZIP-8 increased in CCT-LC cells culminating in reduced cadmium accumulation, suggesting adaptation to the metal. Overall, these data suggest that exposure of human lung epithelial cells to cadmium causes acquisition of cancer cell characteristics. Furthermore, transformation occurs despite the cell's ability to adapt to chronic cadmium exposure. - Highlights: • Chronic cadmium exposure induces cancer cell characteristics in human lung cells. • This provides an in vitro model of cadmium-induced human lung cell transformation. • This occurred with general and lung specific changes typical for cancer cells. • These findings add insight to the

  12. Chronic cadmium exposure in vitro induces cancer cell characteristics in human lung cells

    Cadmium is a known human lung carcinogen. Here, we attempt to develop an in vitro model of cadmium-induced human lung carcinogenesis by chronically exposing the peripheral lung epithelia cell line, HPL-1D, to a low level of cadmium. Cells were chronically exposed to 5 μM cadmium, a noncytotoxic level, and monitored for acquired cancer characteristics. By 20 weeks of continuous cadmium exposure, these chronic cadmium treated lung (CCT-LC) cells showed marked increases in secreted MMP-2 activity (3.5-fold), invasion (3.4-fold), and colony formation in soft agar (2-fold). CCT-LC cells were hyperproliferative, grew well in serum-free media, and overexpressed cyclin D1. The CCT-LC cells also showed decreased expression of the tumor suppressor genes p16 and SLC38A3 at the protein levels. Also consistent with an acquired cancer cell phenotype, CCT-LC cells showed increased expression of the oncoproteins K-RAS and N-RAS as well as the epithelial-to-mesenchymal transition marker protein Vimentin. Metallothionein (MT) expression is increased by cadmium, and is typically overexpressed in human lung cancers. The major MT isoforms, MT-1A and MT-2A were elevated in CCT-LC cells. Oxidant adaptive response genes HO-1 and HIF-1A were also activated in CCT-LC cells. Expression of the metal transport genes ZNT-1, ZNT-5, and ZIP-8 increased in CCT-LC cells culminating in reduced cadmium accumulation, suggesting adaptation to the metal. Overall, these data suggest that exposure of human lung epithelial cells to cadmium causes acquisition of cancer cell characteristics. Furthermore, transformation occurs despite the cell's ability to adapt to chronic cadmium exposure. - Highlights: • Chronic cadmium exposure induces cancer cell characteristics in human lung cells. • This provides an in vitro model of cadmium-induced human lung cell transformation. • This occurred with general and lung specific changes typical for cancer cells. • These findings add insight to the relationship

  13. Diffuse parenchymal lung disease in a case of chronic arsenic exposure

    Somnath Bhattacharya

    2016-01-01

    Full Text Available A 42-year-old housewife, the resident of rural part of West Bengal, presented with gradually progressive exertional dyspnea associated with a dry cough for last 3 years clinical features were suggestive of diffuse parenchymal lung disease (DPLD. Her chest X-ray posteroanterior view and high resolution computed tomography scan of the thorax showed bilateral patchy ground glass opacities and reticulonodular pattern. Search for the etiology revealed classical skin findings of chronic arsenic exposure in the form of generalized darkening and thickening of skin and keratotic lesions over the palms and soles and classical raindrop pigmentation over leg which was present for last 7 years subsequently her bronchoalveolar lavage fluid, hair, nail, and drinking water showed significant amount of arsenic contamination. By exclusion of all known causes of DPLD, we concluded that it was a case of DPLD due to chronic arsenic exposure. To the best of our knowledge, only few case report of DPLD in chronic arsenicosis has been reported till date.

  14. Effects of chronic occupational exposure to anaesthetic gases on the rate of neutrophil apoptosis among anaesthetists.

    Tyther, R

    2012-02-03

    BACKGROUND AND OBJECTIVE: Volatile anaesthetic agents are known to influence neutrophil function. The aim was to determine the effect of chronic occupational exposure to volatile anaesthetic agents on the rate of neutrophil apoptosis among anaesthetists. To test this hypothesis, we compared the rate of neutrophil apoptosis in anaesthetists who had been chronically exposed to volatile anaesthetic agents with that in unexposed volunteers. METHODS: Venous blood (20 mL) was withdrawn from 24 ASA I-II volunteers, from which neutrophils were isolated, and maintained in culture. At 1, 12 and 24 h in culture, the percentage of neutrophil apoptosis was assessed by dual staining with annexin V-FITC and propidium iodide. RESULTS: At 1 h (but not at 12 and 24 h) in culture, the rate of neutrophil apoptosis was significantly less in the anaesthetists--13.8 (12.9%) versus 34.4 (12.1%) (P = 0.001). CONCLUSIONS: Chronic occupational exposure to volatile anaesthetic agents may inhibit neutrophil apoptosis. This may have implications for anaesthetists and similarly exposed healthcare workers in terms of the adequacy of their inflammatory response.

  15. Striatal proteomic analysis suggests that first L-dopa dose equates to chronic exposure.

    Birger Scholz

    Full Text Available L-3,4-dihydroxypheylalanine (L-dopa-induced dyskinesia represent a debilitating complication of therapy for Parkinson's disease (PD that result from a progressive sensitization through repeated L-dopa exposures. The MPTP macaque model was used to study the proteome in dopamine-depleted striatum with and without subsequent acute and chronic L-dopa treatment using two-dimensional difference in-gel electrophoresis (2D-DIGE and mass spectrometry. The present data suggest that the dopamine-depleted striatum is so sensitive to de novo L-dopa treatment that the first ever administration alone would be able (i to induce rapid post-translational modification-based proteomic changes that are specific to this first exposure and (ii, possibly, lead to irreversible protein level changes that would be not further modified by chronic L-dopa treatment. The apparent equivalence between first and chronic L-dopa administration suggests that priming would be the direct consequence of dopamine loss, the first L-dopa administrations only exacerbating the sensitization process but not inducing it.

  16. Chronic 835-MHz radiofrequency exposure to mice hippocampus alters the distribution of calbindin and GFAP immunoreactivity.

    Maskey, Dhiraj; Pradhan, Jonu; Aryal, Bijay; Lee, Chang-Min; Choi, In-Young; Park, Ki-Sup; Kim, Seok Bae; Kim, Hyung Gun; Kim, Myeung Ju

    2010-07-30

    Exponential interindividual handling in wireless communication system has raised possible doubts in the biological aspects of radiofrequency (RF) exposure on human brain owing to its close proximity to the mobile phone. In the nervous system, calcium (Ca(2+)) plays a critical role in releasing neurotransmitters, generating action potential and membrane integrity. Alterations in intracellular Ca(2+) concentration trigger aberrant synaptic action or cause neuronal apoptosis, which may exert an influence on the cellular pathology for learning and memory in the hippocampus. Calcium binding proteins like calbindin D28-K (CB) is responsible for the maintaining and controlling Ca(2+) homeostasis. Therefore, in the present study, we investigated the effect of RF exposure on rat hippocampus at 835 MHz with low energy (specific absorption rate: SAR=1.6 W/kg) for 3 months by using both CB and glial fibrillary acidic protein (GFAP) specific antibodies by immunohistochemical method. Decrease in CB immunoreactivity (IR) was noted in exposed (E1.6) group with loss of interneurons and pyramidal cells in CA1 area and loss of granule cells. Also, an overall increase in GFAP IR was observed in the hippocampus of E1.6. By TUNEL assay, apoptotic cells were detected in the CA1, CA3 areas and dentate gyrus of hippocampus, which reflects that chronic RF exposure may affect the cell viability. In addition, the increase of GFAP IR due to RF exposure could be well suited with the feature of reactive astrocytosis, which is an abnormal increase in the number of astrocytes due to the loss of nearby neurons. Chronic RF exposure to the rat brain suggested that the decrease of CB IR accompanying apoptosis and increase of GFAP IR might be morphological parameters in the hippocampus damages. PMID:20546709

  17. Hypothermia after chronic mild stress exposure in rats with a history of postnatal maternal separations.

    Mrdalj, Jelena; Lundegaard Mattson, Ase; Murison, Robert; Konow Jellestad, Finn; Milde, Anne Marita; Pallesen, Ståle; Ursin, Reidun; Bjorvatn, Bjørn; Grønli, Janne

    2014-03-01

    The circadian system develops and changes in a gradual and programmed process over the lifespan. Early in life, maternal care represents an important zeitgeber and thus contributes to the development of circadian rhythmicity. Exposure to early life stress may affect circadian processes and induce a latent circadian disturbance evident after exposure to later life stress. Disturbance of the normal regulation of circadian rhythmicity is surmised to be an etiological factor in depression. We used postnatal maternal separation in rats to investigate how the early life environment might modify the circadian response to later life unpredictable and chronic stress. During postnatal days 2-14, male Wistar rats (n = 8 per group) were daily separated from their mothers for a period of either 180 min (long maternal separation; LMS) or 10 min (brief maternal separation; BMS). In adulthood, rats were exposed to chronic mild stress (CMS) for 4 weeks. Body temperature, locomotor activity and heart rate were measured and compared before and after CMS exposure. LMS offspring showed a delayed body temperature acrophase compared to BMS offspring. Otherwise, adult LMS and BMS offspring demonstrated similar diurnal rhythms of body temperature, locomotor activity and heart rate. Exposure to CMS provoked a stronger and longer lasting hypothermia in LMS rats than in BMS rats. The thermoregulatory response appears to be moderated by maternal care following reunion, an observation made in the LMS group only. The results show that early life stress (LMS) in an early developmental stage induced a thermoregulatory disturbance evident upon exposure to unpredictable adult life stressors. PMID:24156523

  18. Chronic Exposure to Particulate Nickel Induces Neoplastic Transformation in Human Lung Epithelial Cells

    Amie L. Holmes

    2013-11-01

    Full Text Available Nickel is a well-known human lung carcinogen with the particulate form being the most potent; however, the carcinogenic mechanism remains largely unknown. Few studies have investigated the genotoxicity and carcinogenicity of nickel in its target cell, human bronchial epithelial cells. Thus, the goal of this study was to investigate the effects of particulate nickel in human lung epithelial cells. We found that nickel subsulfide induced concentration- and time-dependent increases in both cytotoxicity and genotoxicity in human lung epithelial cells (BEP2D. Chronic exposure to nickel subsulfide readily induced cellular transformation, inducing 2.55, 2.9 and 2.35 foci per dish after exposure to 1, 2.5 and 5 μg/cm2 nickel subsulfide, respectively. Sixty-one, 100 and 70 percent of the foci isolated from 1, 2.5, and 5 μg/cm2 nickel subsulfide treatments formed colonies in soft agar and the degree of soft agar colony growth increased in a concentration-dependent manner. Thus, chronic exposure to particulate nickel induces genotoxicity and cellular transformation in human lung epithelial cells.

  19. Reproduction recovery of the crustacean Daphnia magna after chronic exposure to ibuprofen.

    Hayashi, Yuya; Heckmann, Lars-Henrik; Callaghan, Amanda; Sibly, Richard M

    2008-05-01

    In mammals, the pharmaceutical ibuprofen (IB), a non-steroidal anti-inflammatory drug, primarily functions by reversibly inhibiting the cyclooxygenase (COX) pathway in the synthesis of eicosanoids (e.g. prostaglandins). Previous studies suggest that IB may act in a similar manner to interrupt production of eicosanoids reducing reproduction in the model crustacean Daphnia magna. On this basis withdrawal of IB should lead to the recovery of D. magna reproduction. Here we test whether the effect of IB is reversible in D. magna, as it is in mammals, by observing reproduction recovery following chronic exposure. D. magna (5-days old) were exposed to a range of IB concentrations (0, 20, 40 and 80 mg l(-1)) for 10 days followed by a 10 day recovery period in uncontaminated water. During the exposure period, individuals exposed to higher concentrations produced significantly fewer offspring. Thereafter, IB-stressed individuals produced offspring faster during recovery, having similar average population growth rates (PGR) (1.15-1.28) to controls by the end of the test. It appears that maternal daphnids are susceptible to IB during egg maturation. This is the first recorded recovery of reproduction in aquatic invertebrates that suffered reproductive inhibition during chronic exposure to a chemical stressor. Our results suggest a possible theory behind the compensatory fecundity that we referred to as 'catch-up reproduction'. PMID:18214676

  20. Metabolic and histopathological alterations in the marine bivalve Mytilus galloprovincialis induced by chronic exposure to acrylamide.

    Larguinho, Miguel; Cordeiro, Ana; Diniz, Mário S; Costa, Pedro M; Baptista, Pedro V

    2014-11-01

    Although the neurotoxic and genotoxic potential of acrylamide has been established in freshwater fish, the full breadth of the toxicological consequences induced by this xenobiotic has not yet been disclosed, particularly in aquatic invertebrates. To assess the effects of acrylamide on a bivalve model, the Mediterranean mussel (Mytilus galloprovincialis), two different setups were accomplished: 1) acute exposure to several concentrations of waterborne acrylamide to determine lethality thresholds of the substance and 2) chronic exposure to more reduced acrylamide concentrations to survey phases I and II metabolic endpoints and to perform a whole-body screening for histopathological alterations. Acute toxicity was low (LC50≈400mg/L). However, mussels were responsive to prolonged exposure to chronic concentrations of waterborne acrylamide (1-10mg/L), yielding a significant increase in lipid peroxidation plus EROD and GST activities. Still, total anti-oxidant capacity was not exceeded. In addition, no neurotoxic effects could be determined through acetylcholine esterase (AChE) activity. The findings suggest aryl-hydrocarbon receptor (Ahr)-dependent responses in mussels exposed to acrylamide, although reduced comparatively to vertebrates. No significant histological damage was found in digestive gland or gills but female gonads endured severe necrosis and oocyte atresia. Altogether, the results indicate that acrylamide may induce gonadotoxicity in mussels, although the subject should benefit from further research. Altogether, the findings suggest that the risk of acrylamide to aquatic animals, especially molluscs, may be underestimated. PMID:25262075

  1. Chronic exposure to ethanol in male mice may be associated with hearing loss in offspring

    Fei Liang

    2015-01-01

    Full Text Available Although paternal ethanol (EtOH abuse has been shown to affect the growth and behavior of offspring, the exact molecular and mechanistic basis remains largely unclear. Methylation alterations in imprinted genes may be related to well-documented teratogenic effects of ethanol. Here we show that chronic paternal ethanol exposure increases the susceptibility to abnormal behavior in offspring through male game epigenetic alteration. In our study, different doses of ethanol (0, 1.1, 3.3 g kg−1 were administered intra-gastrically to male mice and decreased sperm motility was found in the highest ethanol-exposed group compared with the controls. Data also showed a dose-dependent increase in deaf mice of the paternally ethanol-exposed groups. The methylation of H19, Peg3, Ndn and Snrpn was assessed in paternal spermatozoa and in the cerebral cortices of deaf mice. EtOH affected methylation of Peg3 (CpG 3, 7 and 9 in paternal spermatozoa and in the cerebral cortices of deaf mice, but the level of mRNA expression did not change, suggesting that other gene regulation may be involved in these processes. Overall, chronic paternal ethanol exposure could alter the methylation of imprinted genes in sire spermatozoa that could also be passed on to offspring, giving rise to developmental disorders. Our results provide possible epigenetic evidence for a paternal ethanol exposure contribution to Fetal Alcohol Syndrome (FAS.

  2. Chronic exposure to trichloroethene causes early onset of SLE-like disease in female MRL +/+ mice

    Trichloroethene (TCE) exacerbates the development of autoimmune responses in autoimmune-prone MRL +/+ mice. Although TCE-mediated autoimmune responses are associated with an increase in serum immunoglobulins and autoantibodies, the underlying mechanism of autoimmunity is not known. To determine the progression of TCE-mediated immunotoxicity, female MRL +/+ mice were chronically exposed to TCE through the drinking water (0.5 mg/ml of TCE) for various periods of time. Serum concentrations of antinuclear antibodies increased after 36 and 48 weeks of TCE exposure. Histopathological analyses showed lymphocyte infiltration in the livers of MRL +/+ mice exposed to TCE for 36 or 48 weeks. Lymphocyte infiltration was also apparent in the pancreas, lungs, and kidneys of mice exposed to TCE for 48 weeks. Immunoglobulin deposits in kidney glomeruli were found after 48 weeks of exposure to TCE. Our results suggest that chronic exposure to TCE promotes inflammation in the liver, pancreas, lungs, and kidneys, which may lead to SLE-like disease in MRL +/+ mice

  3. The effect of chronic exposure to tobacco smoke on the antibacterial defenses of the lung.

    Huber, G L; Pochay, V E; Mahajan, V K; McCarthy, C R; Hinds, W C; Davies, P; Drath, D B; Sornberger, G C

    1977-01-01

    To evaluate the effects of cigarette smoking on the host defenses of the lung, male CD rats were exposed to fresh whole smoke for up to 60 consecutive days. Intrapulmonary deposition of smoke and animal exposure levels, quantified with decachlorobiphenyl and other smoke tracers, indicated a daily cigarette exposure equivalent to approximately a pack and a half per day in man. Pulmonary alveolar macrophage function in situ was quantified by the inactivation of an aerosolized challenge of Staphylococcus aureus six hours after inoculation. Controls (n=120) inactivated 88.8+/-0.64% of the staphylococci. Exposure to whole smoke did not impair intrapulmonary antistaphylococcal defenses, with inactivation rates of 89.8+/-0.97% (n=49) and 89.1+/-0.46% (n=74) at 30 and 60 days, respectively. Inactivation distribution frequency analysis in controls revealed that 7% of animals had inactivation values greater than two standard deviations from the mean. With prolonged exposure mean with less skewing towards the abnormal. Alveolar macrophages harvested from smoked animals were comparable in viability and in vitro antistaphylococcal activity to controls, appeared to be metabolically activated and had specific stereologic ultrastructural alterations. These studies indicate that chronic exposure to tobacco smoke does not impair, and in fact may stimulate, the host defenses of the lung, as evaluated by in vivo and in vitro pulmonary alveolar macrophage function. PMID:843645

  4. Effects of chronic carbon monoxide exposure on fetal growth and development in mice

    Venditti Carolina C

    2011-12-01

    Full Text Available Abstract Background Carbon monoxide (CO is produced endogenously, and can also be acquired from many exogenous sources: ie. cigarette smoking, automobile exhaust. Although toxic at high levels, low level production or exposure lends to normal physiologic functions: smooth muscle cell relaxation, control of vascular tone, platelet aggregation, anti- inflammatory and anti-apoptotic events. In pregnancy, it is unclear at what level maternal CO exposure becomes toxic to the fetus. In this study, we hypothesized that CO would be embryotoxic, and we sought to determine at what level of chronic CO exposure in pregnancy embryo/fetotoxic effects are observed. Methods Pregnant CD1 mice were exposed to continuous levels of CO (0 to 400 ppm from conception to gestation day 17. The effect on fetal/placental growth and development, and fetal/maternal CO concentrations were determined. Results Maternal and fetal CO blood concentrations ranged from 1.12- 15.6 percent carboxyhemoglobin (%COHb and 1.0- 28.6%COHb, respectively. No significant difference was observed in placental histological morphology or in placental mass with any CO exposure. At 400 ppm CO vs. control, decreased litter size and fetal mass (p Conclusions Exposure to levels at or below 300 ppm CO throughout pregnancy has little demonstrable effect on fetal growth and development in the mouse.

  5. Persistent modification of Nav1.9 following chronic exposure to insecticides and pyridostigmine bromide

    Many veterans of the 1991 Gulf War (GW) returned from that conflict with a widespread chronic pain affecting deep tissues. Recently, we have shown that a 60 day exposure to the insecticides permethrin, chlorpyrifos, and pyridostigmine bromide (NTPB) had little influence on nociceptor action potential forming Nav1.8, but increased Kv7 mediated inhibitory currents 8 weeks after treatment. Using the same exposure regimen, we used whole cell patch methods to examine whether the influences of NTPB could be observed on Nav1.9 expressed in muscle and vascular nociceptors. During a 60 day exposure to NTPB, rats exhibited lowered muscle pain thresholds and increased rest periods, but these measures subsequently returned to normal levels. Eight and 12 weeks after treatments ceased, DRG neurons were excised from the sensory ganglia. Whole cell patch studies revealed little change in voltage dependent activation and deactivation of Nav1.9, but significant increases in the amplitude of Nav1.9 were observed 8 weeks after exposure. Cellular studies, at the 8 week delay, revealed that NTPB also significantly prolonged action potential duration and afterhyperpolarization (22 °C). Acute application of permethrin (10 μM) also increased the amplitude of Nav1.9 in skin, muscle and vascular nociceptors. In conclusion, chronic exposure to Gulf War agents produced long term changes in the amplitude of Nav1.9 expressed in muscle and vascular nociceptors. The reported increases in Kv7 amplitude may have been an adaptive response to increased Nav1.9, and effectively suppressed behavioral pain measures in the post treatment period. Factors that alter the balance between Nav1.9 and Kv7 could release spontaneous discharge and produce chronic deep tissue pain. - Highlights: • Rats were treated 60 days with permethrin, chlorpyrifos and pyridostigmine bromide. • 8 weeks after treatments, Nav1.9 activation and deactivation were unchanged. • The amplitude and conductance of Nav1.9 were

  6. Health care workers and AIDS: a differential study of beliefs and affects associated with accidental exposure to blood Profissionais de saúde e AIDS: um estudo diferencial sobre crenças e afetos associados à experiência de exposição acidental a material biológico potencialmente contaminado

    Maria Rosa Rodrigues Rissi; Alcyone Artioli Machado; Marco Antonio de Castro Figueiredo

    2005-01-01

    This study aimed to analyze affective and cognitive determinants of the professional work of individuals caring for patients with HIV/AIDS, in view of the risk and/or experience of accidental exposure to blood. We drew on the theoretical-methodological references of Fishbein & Ajzen and Maslow's theory. Fifty health care workers were evaluated using an attitudes questionnaire and a needs and motivations instrument. The research verified differences between answers by health care workers who h...

  7. Quantifying Chronic Stress Exposure for Cumulative Risk Assessment: Lessons Learned from a Case Study of Allostatic Load

    Although multiple methods of quantifying environmental chemical exposures have been validated for use in human health risk assessment, quantifying chronic stress exposure is more challenging. Stress is a consequence of perceiving an “exposure” (e.g., violence, poverty) as more th...

  8. Reduced gene expression levels after chronic exposure to high concentrations of air pollutants

    Rössner ml., Pavel; Tulupová, Elena; Rössnerová, Andrea; Líbalová, Helena; Hoňková, Kateřina; Gmuender, H.; Pastorková, Anna; Švecová, Vlasta; Topinka, Jan; Šrám, Radim

    2015-01-01

    Roč. 780, oct (2015), s. 60-70. ISSN 0027-5107 R&D Projects: GA MŽP(CZ) SP/1B3/8/08; GA MŠk(CZ) LO1508; GA ČR GA13-13458S; GA MŠk 2B08005 Institutional support: RVO:68378041 Keywords : chronic exposure * air pollution * gene expression profiles * human health * particulate matter * polycyclic aromatic hydrocarbons Subject RIV: DN - Health Impact of the Environment Quality Impact factor: 3.680, year: 2014

  9. Chronic exposure to a beta 2-adrenoceptor agonist increases the airway response to methacholine.

    Witt-Enderby, P A; Yamamura, H I; Halonen, M; Palmer, J D; Bloom, J W

    1993-09-01

    Scheduled chronic administration of beta 2-adrenoceptor agonist bronchodilators in patients with asthma recently has been reported to be associated with a worsening of symptoms and an increase in bronchial responsiveness. We wanted to determine whether a 28-day in vivo exposure to albuterol (beta 2-adrenoceptor agonist) altered the response of rabbit airways to the cholinergic agonist methacholine. We found, using in vitro tissue bath techniques, that in mainstem bronchi from rabbits given a 28-day exposure to albuterol, maximum contraction to methacholine was increased in the albuterol-treated group (control group = 1.10 +/- 0.11 g vs. treated group = 1.50 +/- 0.13 g, P airway smooth muscle to methacholine.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7901034

  10. Lactobacillus rhamnosus GG Effect on Behavior of Zebrafish During Chronic Ethanol Exposure.

    Schneider, Ana Claudia Reis; Rico, Eduardo Pacheco; de Oliveira, Diogo Losch; Rosemberg, Denis Broock; Guizzo, Ranieli; Meurer, Fábio; da Silveira, Themis Reverbel

    2016-01-01

    Ethanol is a widely consumed drug, which acts on the central nervous system to induce behavioral alterations ranging from disinhibition to sedation. Recent studies have produced accumulating evidence for the therapeutic role of probiotic bacteria in behavior. We aimed to investigate the effect of Lactobacillus rhamnosus GG (LGG) on the behavior of adult zebrafish chronically exposed to ethanol. Adult wild-type zebrafish were randomly divided into four groups, each containing 15 fish. The following groups were formed: Control (C), received unsupplemented feed during the trial period; Probiotic (P), fed with feed supplemented with LGG; Ethanol (E), received unsupplemented feed and 0.5% of ethanol directly added to the tank water; and Probiotic+Ethanol (P+E), group under ethanol exposure (0.5%) and fed with LGG supplemented feed. After 2 weeks of exposure, the novel tank test was used to evaluate fish behavior, which was analyzed using computer-aided video tracking. LGG alone did not alter swimming behavior of the fish. Ethanol exposure led to robust behavioral effects in the form of reduced anxiety levels, as indicated by increased vertical exploration and more time spent in the upper region of the novel tank. The group exposed to ethanol and treated with LGG behaved similarly to animals exposed to ethanol alone. Taken together, these results show that zebrafish behavior was not altered by LGG per se, as seen in murine models. This was the first study to investigate the effects of a probiotic diet on behavior after a chronic ethanol exposure. PMID:26862467

  11. Growth Responses of Fish During Chronic Exposure of Metal Mixture under Laboratory Conditions

    Saima Naz and Muhammad Javed

    2013-07-01

    Full Text Available Growth responses of five fish species viz. Catla catla, Labeo rohita, Cirrhina mrigala, Ctenopharyngodon idella and Hypophthalmichthys molitrix were determined, separately, under chronic exposure of binary mixture of metals (Zn+Ni at sub-lethal concentrations (1/3rd of LC50 for 12 weeks. Randomized complete block design (RCBD was followed to conduct this research work. The groups (10 fish each of Catla catla, Labeo rohita, Cirrhina mrigala, Ctenopharyngodon idella and Hypophthalmichthys molitrix having almost similar weights were investigated for their growth responses and metals bioaccumulation patterns in their body organs during chronic exposure of Zn+Ni mixture. The bioaccumulation of metals in the fish body organs viz. gills, liver, kidney, fins, bones, muscle and skin were also determined before and after growth trails under the stress of metals mixture. The exposure of fish to sub-lethal concentrations of mixture caused significant impacts on the average wet weight increments of five fish species. Ctenopharyngodon idella and Labeo rohita attained significantly higher weights, followed by that of Hypophthalmichthys molitrix, Cirrhina mrigala and Catla catla. However, the growth of metals mixture exposed fish species was significantly lesser than that of control fish (un-stressed. Significantly variable condition factor values reflected the degree of fish well-beings that correlated directly with fish growth and metal exposure concentration. Any significant change in feed intake, due to stress, is reflected in terms of fish growth showing the impacts of metal mixture on fish growth were either additive or antagonist / synergistic. Accumulation of all the metals in fish body followed the general order: liver>kidney>gills> skin >muscle> fins >bones.

  12. Effects of Acute and Chronic Heavy Metal (Cu, Cd, and Zn) Exposure on Sea Cucumbers (Apostichopus japonicus).

    Li, Li; Tian, Xiangli; Yu, Xiao; Dong, Shuanglin

    2016-01-01

    Acute and chronic toxicity tests were conducted with sea cucumber (Apostichopus japonicus) exposed to heavy metals. Acute toxicity values (96 h LC50) were 2.697, 0.133, and 1.574 mg L(-1) for Zn, Cu, and Cd, respectively, and were ranked in order of toxicity: Cu > Cd > Zn. Under chronic metal exposure the specific growth rates of sea cucumbers decreased with the increase of metal concentration for all the three metals. After acute metal exposure, the oxygen consumption rate (OCR) decreased. The OCRs in all groups were significantly different than control (P muscle > intestine in natural sea water. After chronic Zn, Cu, and Cd exposure, the change pattern of HK and PK in respiratory tree, muscle, and intestine varied slightly. However, the activity of the enzyme showed a general trend of increase and then decrease and the higher the exposure concentration was, the earlier the highest point of enzyme activity was obtained. PMID:27382568

  13. Effect of chronic and subchronic organic solvents exposure on balance control of workers in plant manufacturing adhesive materials.

    Herpin, Guillaume; Gargouri, Imed; Gauchard, Gérome C; Nisse, Catherine; Khadhraoui, Moncef; Elleuch, Boubaker; Zmirou-Navier, Denis; Perrin, Philippe P

    2009-02-01

    High-level occupational exposure to volatile organic solvents may elicit neurotoxic effects, especially on central and peripheral structures involved in balance ability. Studies on balance control in relation with exposure levels close to the threshold limit values are scarce. This study aimed to assess the neurotoxic effects of chronic and subchronic exposure to organic solvents among workers in plant manufacturing adhesive materials. Balance control was evaluated in 18 subjects, mainly exposed to n-hexane and toluene, with current median exposure levels of 222 and 102 mg/m(3), respectively, and a median exposure duration of 21 years, and in 32 nonexposed controls, using posturography tests with and without sensory conflicting situations. Tests were undergone at the beginning of the work shift (chronic exposure) following a week end, and after 72 h (subchronic exposure). Balance control performance was lower in chronically exposed workers compared to controls, and got worse after subchronic exposure, particularly during situations, where vestibular information was important. Our study suggests that a low-level and prolonged exposure to volatile organic solvents, mainly n-hexane and toluene, in the workplace is associated with deleterious central effects involved in postural regulation. This neurotoxicity is characterized by difficulties to use the most relevant information to control balance, leading to altered management of sensory conflicting situations. PMID:19384580

  14. Continuous exposure to house dust mite elicits chronic airway inflammation and structural remodeling.

    Johnson, Jill R; Wiley, Ryan E; Fattouh, Ramzi; Swirski, Filip K; Gajewska, Beata U; Coyle, Anthony J; Gutierrez-Ramos, José-Carlos; Ellis, Russ; Inman, Mark D; Jordana, Manel

    2004-02-01

    It is now fully appreciated that asthma is a disease of a chronic nature resulting from intermittent or continued aeroallergen exposure leading to airway inflammation. To investigate responses to continuous antigen exposure, mice were exposed to either house dust mite extract (HDM) or ovalbumin intranasally for five consecutive days, followed by 2 days of rest, for up to seven consecutive weeks. Continuous exposure to HDM, unlike ovalbumin, elicited severe and persistent eosinophilic airway inflammation. Flow cytometric analysis demonstrated an accumulation of CD4+ lymphocytes in the lung with elevated expression of inducible costimulator a marker of T cell activation, and of T1/ST2, a marker of helper T Type 2 effector cells. We also detected increased and sustained production of helper T cell Type 2-associated cytokines by splenocytes of HDM-exposed mice on in vitro HDM recall. Histologic analysis of the lung showed evidence of airway remodeling in mice exposed to HDM, with goblet cell hyperplasia, collagen deposition, and peribronchial accumulation of contractile tissue. In addition, HDM-exposed mice demonstrated severe airway hyperreactivity to methacholine. Finally, these responses were studied for up to 9 weeks after cessation of HDM exposure. We observed that whereas airway inflammation resolved fully, the remodeling changes did not resolve and airway hyperreactivity resolved only partly. PMID:14597485

  15. Investigations of subclinical neurogenous damage of persons with chronic occupational exposure to lead and trichlorethylene

    Reichenbach, T.

    1980-12-15

    The functions of the peripheral nervous system, for example the maximum and minimum conduction velocities of the ulnar and the radial nerves, were measured in 22 men and 9 women with occupational exposure to lead and in 20 men and 20 women without occupational exposure to lead. The result of the comparison of the obtained measuring values was a decrease of the minimum conduction velocity of the ulnar nerve of the working hand of men exposed to lead. In order to quantify the lead exposure we determined in all test persons the blood lead level, the concentration of free erythrocyteporphyrines in the blood and the hemoglobin concentration. The study reports also about the elcetroneurographic investigations on 7 persons with chronical exposure to trichloroethylene and on 13 comparable persons of a corresponding age group. A correlation between the biochemical and toxicologic parameters and the nervous conduction velocities could be detected neither in the persons exposed to lead nor in those exposed to trichloroethylene. The measured nervous conduction velocities are well comparable with those age-specific indications given in the specialised literature. The dependence of conduction velocity on various parameters as age, temperature, left- or righthandedness and sex is discussed.

  16. Health care workers and AIDS: a differential study of beliefs and affects associated with accidental exposure to blood Profissionais de saúde e AIDS: um estudo diferencial sobre crenças e afetos associados à experiência de exposição acidental a material biológico potencialmente contaminado

    Maria Rosa Rodrigues Rissi

    2005-02-01

    Full Text Available This study aimed to analyze affective and cognitive determinants of the professional work of individuals caring for patients with HIV/AIDS, in view of the risk and/or experience of accidental exposure to blood. We drew on the theoretical-methodological references of Fishbein & Ajzen and Maslow's theory. Fifty health care workers were evaluated using an attitudes questionnaire and a needs and motivations instrument. The research verified differences between answers by health care workers who had never suffered accidents and those who had already experienced accidental exposure to blood. Health care workers did their work activities motivated by the need for self-fulfillment and valued their own performance when they were able to meet the patients' emotional needs. Among health professionals who had never experienced accidental exposure to blood, the predominant beliefs was that patients feel remorse over having expose themselves to HIV. Accidental exposure to blood raises difficulties in personal life. Technical aspects are also associated with the possibility of accidental exposure to blood.O objetivo deste estudo foi analisar determinantes afetivos e cognitivos que influenciam o trabalho de profissionais que cuidam de pessoas vivendo com o HIV/ AIDS, frente ao risco ou experiência de exposição acidental a material biológico potencialmente contaminado (MBPC. Utilizou-se o referencial teórico metodológico de Fishbein-Ajzen e a teoria de Maslow, que propõe a hierarquia das necessidades humanas. Cinqüenta profissionais de saúde foram avaliados por meio de escalas de atitudes, e de um instrumento de avaliação de necessidades e motivações. Verificou-se a diferença entre as respostas de profissionais que nunca sofreram acidente e aqueles que já passaram pela experiência de acidente ocupacional. Os resultados indicam que os profissionais exercem suas atividades motivados pela necessidade de auto-realização e valorizam sua performance

  17. Effects of a chronic lower range of triclosan exposure to a stream mesocosm community

    Nietch, C.T.; Quinlan, E.L.; Lazorchak, J.; Impellitteri, C.; Raikow, D.; Walters, David M.

    2013-01-01

    Triclosan (5-chloro-2-(2,4-dichlorophenoxy)phenol) is an antimicrobial found in consumer soaps and toothpaste. It is in treated wastewater effluents at low part per billion concentrations, representing a potentially chronic exposure condition for biota inhabiting receiving streams. A naturally colonized benthos was created using flow-through indoor mesocosms. Then the benthic communities were dosed to achieve different in-stream triclosan concentrations (Control, 0.1, 0.5, 1.0, 5.0, and 10 µg/L) for 56 days. Water quality parameters and endpoints from bacteria to macroinvertebrates plus interacting abiotic components were measured. Effects of triclosan on specific microbial endpoints were observed at all doses, including an effect on litter decomposition dynamics at doses 1.0 µg/L and higher. Resistance of periphytic bacteria to triclosan significantly increased in doses 0.5 µg/L and above. By the end of dosing, the antimicrobial appeared to stimulate the stream periphyton at the three lowest doses while the two highest doses exhibited decreased stocks of periphyton, including significantly lower bacteria cell densities, and cyanobacteria abundance compared to the control. Beside an effect on benthic ostracods, the changes that occurred in the periphyton did not translate to significant change in the colonizing nematodes, the macroinvertebrate community as a whole, or other measurements of stream function. The results shed light on the role a low, chronic exposure to triclosan may play in effluent dominated streams.

  18. Altered social cognition in male BDNF heterozygous mice and following chronic methamphetamine exposure.

    Manning, Elizabeth E; van den Buuse, Maarten

    2016-05-15

    Growing clinical evidence suggests that persistent psychosis which occurs in methamphetamine users is closely related to schizophrenia. However, preclinical studies in animal models have focussed on psychosis-related behaviours following methamphetamine, and less work has been done to assess endophenotypes relevant to other deficits observed in schizophrenia. Altered social behaviour is a feature of both the negative symptoms and cognitive deficits in schizophrenia, and significantly impacts patient functioning. We recently found that brain-derived neurotrophic factor (BDNF) heterozygous mice show disrupted sensitization to methamphetamine, supporting other work suggesting an important role of this neurotrophin in the pathophysiology of psychosis and the neuronal response to stimulant drugs. In the current study, we assessed social and cognitive behaviours in methamphetamine-treated BDNF heterozygous mice and wildtype littermate controls. Following chronic methamphetamine exposure male wildtype mice showed a 50% reduction in social novelty preference. Vehicle-treated male BDNF heterozygous mice showed a similar impairment in social novelty preference, with a trend for no further disruption by methamphetamine exposure. Female mice were unaffected in this task, and no groups showed any changes in sociability or short-term spatial memory. These findings suggest that chronic methamphetamine alters behaviour relevant to disruption of social cognition in schizophrenia, supporting other studies which demonstrate a close resemblance between persistent methamphetamine psychosis and schizophrenia. Together these findings suggest that dynamic regulation of BDNF signalling is necessary to mediate the effects of methamphetamine on behaviours relevant to schizophrenia. PMID:26965573

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

    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

  20. Effects of Chronic Exposure to Sodium Arsenate on Kidney of Rats

    Namdar Yousofvand

    2015-09-01

    Full Text Available Background: In the present study, histopathological effects of chronic exposure to sodium arsenate in drinkable water were studied on a quantity of organs of rat. Methods: Rats were divided into two groups, group I; served as control group, were main-tained on deionized drinkable water for 2 months, and group II; the study group were given 60 g/ml of sodium arsenate in deionized drinkable water for 2 months. Blood and urine samples from two groups of animals were collected under anesthesia and the animals were sacrificed under deep anesthesia (a-chloralose, 100 mg/kg, I.P. Their kidney, liver, aorta, and heart were dissected out and cleaned of surrounding connective tissue. The organs were kept in formaldehyde (10% for histopathologic examination. Serum and urine samples from two groups were collected and analyzed for arsenic level. Total quantity of arsenic in serum and urine of animal was measured through graphic furnace atomic absorption spectrometry (GF-AAS. Results:Examination with light microscopy did not show any visible structural changes in the aorta, myocardium, and liver of chronic arsenic treated animals.However, a significant effect was observed in the kidneys of chronic arsenic treated rats showing distinct changes in proxi-mal tubular cells. There was high concentration of arsenic in serum and urine of arsenic ex-posed animals (group II significantly (P<0.001. Conclusion:Swollen tubular cells in histopathologic study of kidney may suggest toxic effects of arsenic in the body.

  1. Acute and chronic ethanol exposure differentially affect induction of hippocampal LTP.

    Fujii, Satoshi; Yamazaki, Yoshihiko; Sugihara, Toshimichi; Wakabayashi, Ichiro

    2008-05-23

    Using hippocampal slices, we found that chronic ethanol consumption by rats induces tolerance to the impairing effects of acute ethanol treatment on induction of long-term potentiation (LTP) in CA1 neurons. In hippocampal slices from pair-fed control rats, stable LTP was induced by tetanic stimulation consisting of 25 or more pulses at 100 Hz, but not by tetanic stimulation of 15 pulses at 100 Hz, and LTP induction was blocked if the tetanus was delivered in the presence of 8.6 mM ethanol, 1 microM muscimol, a gamma-aminobutyric acid (GABA) A receptor agonist, or 2.5 microM dl-2-amino-5-phosphonovaleric acid (AP5), an N-methyl-d-aspartate (NMDA) receptor antagonist. In hippocampal slices from rats chronically fed a liquid diet containing ethanol, a tetanus consisting of 15 pulses at 100 Hz did induce stable LTP, indicating a decrease in the stimulation threshold for inducing LTP. Application of ethanol, muscimol, or AP5 did not affect LTP induction in these cells, suggesting that the effects of chronic ethanol exposure on LTP induction are mediated by a reduction in GABAergic inhibition or an increase in NMDA receptor activity in hippocampal CA1 neurons. PMID:18423576

  2. Effect of chronic exposure to aspartame on oxidative stress in the brain of albino rats

    Ashok Iyyaswamy; Sheeladevi Rathinasamy

    2012-09-01

    This study was aimed at investigating the chronic effect of the artificial sweetener aspartame on oxidative stress in brain regions of Wistar strain albino rats. Many controversial reports are available on the use of aspartame as it releases methanol as one of its metabolite during metabolism. The present study proposed to investigate whether chronic aspartame (75 mg/kg) administration could release methanol and induce oxidative stress in the rat brain. To mimic the human methanol metabolism, methotrexate (MTX)-treated rats were included to study the aspartame effects. Wistar strain male albino rats were administered with aspartame orally and studied along with controls and MTX-treated controls. The blood methanol level was estimated, the animal was sacrificed and the free radical changes were observed in brain discrete regions by assessing the scavenging enzymes, reduced glutathione, lipid peroxidation (LPO) and protein thiol levels. It was observed that there was a significant increase in LPO levels, superoxide dismutase (SOD) activity, GPx levels and CAT activity with a significant decrease in GSH and protein thiol. Moreover, the increases in some of these enzymes were region specific. Chronic exposure of aspartame resulted in detectable methanol in blood. Methanol per se and its metabolites may be responsible for the generation of oxidative stress in brain regions.

  3. Accidental exposures in radiotherapy: an history

    Radiotherapy accidents are exceedingly rare. However, they may have major negative consequences: for health (and sometimes life) of victims as well as for the trust that patients put in radiotherapy and radiation oncolysis. Each accident must be pointed out, analysed and reported, in order to allow preventive actions, avoiding repetitive accidents. Through examples of majors accidents occurred all over the world in the last decades, affecting professionals, public or patients themselves, the necessity of transparency is demonstrated. The International Commission of Radiobiological Protection has drawn positive lessons from such accidents and insists on following recommendations: necessity of sufficient number and competent professionals, importance of continuous and initial education, information of professionals and, in general, a strict Quality Assurance program. It is clear that each radiotherapy center remains at risk for errors. It is essential to develop preventive procedures to avoid transformation of errors into accidents. In that context, complete and detailed description and reports of each anomaly or incident must be encouraged as it is done for sectors of aviation or nuclear industry. Radiation oncology must develop such a culture of transparency and of systematic report of all incident. (authors)

  4. Analysis of dose-rate effects on cellular responses to chronic radiation exposure

    The effects in the title were studied on their expression of various genes concerned with radiation exposure by the acute (1 Gy/min) and chronic (0.007-0.694 Gy/min) irradiations to various cell lines. Cell of human origin were the primarily cultured fibroblasts (F), their immortalized strain (imF) by transduction of human teromerase transcriptase (hTERT), breast cancer MCF-7, osteosarcoma U-20S, colon cancer HCT-116 and T-cell leukemia Jurkat. Acute irradiation was done in a gamma-cell with Cs-137 gamma-ray and chronic one, in a CO2-incubator with the Cs-137 source. Expression of genes was analyzed by mRNA sequence with Genome Analyzer. Proteins of p53, p53-Ser15-P, murine double minute 2 (MDM2), p21 and a/b-tubulin were analyzed by Western blotting. D0 values of acute irradiation were found in the range of 1.1-1.4 Gy, suggesting the similar sensitivity of used cells. However, responses to chronic exposure were different from cells to cells: particularly, at 0.347 mGy/min, no effect on growth was observed in cancer-derived cells until 10 days whereas a marked growth inhibition of F and imF cells was seen after 4 days. Arrest of proliferation of F cells after 10 days exposure at 0.347 mGy/min was tentative, but at 0.694 mGy/min, it was irreversible dependently on the exposure time. They were arrested at G0 stage. Gene expression analyzed by mRNA sequence was shown to be changed even by the lowest rate 0.007 mGy/min: levels of protein expressed under control of cancer-suppressing p53 were markedly altered. Western blotting showed an increased expression of examined proteins except for p53, at higher dose than 0.069 mGy/min. Results indicated that the cellular response to radiation involved not only DNA damage but also the process of yielding the damage. (T.T.)

  5. Microfluidic gradient device for studying mesothelial cell migration and the effect of chronic carbon nanotube exposure

    Cell migration is one of the crucial steps in many physiological and pathological processes, including cancer development. Our recent studies have shown that carbon nanotubes (CNTs), similarly to asbestos, can induce accelerated cell growth and invasiveness that contribute to their mesothelioma pathogenicity. Malignant mesothelioma is a very aggressive tumor that develops from cells of the mesothelium, and is most commonly caused by exposure to asbestos. CNTs have a similar structure and mode of exposure to asbestos. This has raised a concern regarding the potential carcinogenicity of CNTs, especially in the pleural area which is a key target for asbestos-related diseases. In this paper, a static microfluidic gradient device was applied to study the migration of human pleural mesothelial cells which had been through a long-term exposure (4 months) to subcytotoxic concentration (0.02 µg cm−2) of single-walled CNTs (SWCNTs). Multiple migration signatures of these cells were investigated using the microfluidic gradient device for the first time. During the migration study, we observed that cell morphologies changed from flattened shapes to spindle shapes prior to their migration after their sensing of the chemical gradient. The migration of chronically SWCNT-exposed mesothelial cells was evaluated under different fetal bovine serum (FBS) concentration gradients, and the migration speeds and number of migrating cells were extracted and compared. The results showed that chronically SWCNT-exposed mesothelial cells are more sensitive to the gradient compared to non-SWCNT-exposed cells. The method described here allows simultaneous detection of cell morphology and migration under chemical gradient conditions, and also allows for real-time monitoring of cell motility that resembles in vivo cell migration. This platform would be much needed for supporting the development of more physiologically relevant cell models for better assessment and characterization of the

  6. Microfluidic gradient device for studying mesothelial cell migration and the effect of chronic carbon nanotube exposure

    Zhang, Hanyuan; Lohcharoenkal, Warangkana; Sun, Jianbo; Li, Xiang; Wang, Liying; Wu, Nianqiang; Rojanasakul, Yon; Liu, Yuxin

    2016-01-01

    Cell migration is one of the crucial steps in many physiological and pathological processes, including cancer development. Our recent studies have shown that carbon nanotubes (CNTs), similarly to asbestos, can induce accelerated cell growth and invasiveness that contribute to their mesothelioma pathogenicity. Malignant mesothelioma is a very aggressive tumor that develops from cells of the mesothelium, and is most commonly caused by exposure to asbestos. CNTs have a similar structure and mode of exposure to asbestos. This has raised a concern regarding the potential carcinogenicity of CNTs, especially in the pleural area which is a key target for asbestos-related diseases. In this paper, a static microfluidic gradient device was applied to study the migration of human pleural mesothelial cells which had been through a long-term exposure (4 months) to subcytotoxic concentration (0.02 μg cm−2) of single-walled CNTs (SWCNTs). Multiple migration signatures of these cells were investigated using the microfluidic gradient device for the first time. During the migration study, we observed that cell morphologies changed from flattened shapes to spindle shapes prior to their migration after their sensing of the chemical gradient. The migration of chronically SWCNT-exposed mesothelial cells was evaluated under different fetal bovine serum (FBS) concentration gradients, and the migration speeds and number of migrating cells were extracted and compared. The results showed that chronically SWCNT-exposed mesothelial cells are more sensitive to the gradient compared to non-SWCNT-exposed cells. The method described here allows simultaneous detection of cell morphology and migration under chemical gradient conditions, and also allows for real-time monitoring of cell motility that resembles in vivo cell migration. This platform would be much needed for supporting the development of more physiologically relevant cell models for better assessment and characterization of the

  7. Chronic exposure to hypergravity affects thyrotropin-releasing hormone levels in rat brainstem and cerebellum

    Daunton, N. G.; Tang, F.; Corcoran, M. L.; Fox, R. A.; Man, S. Y.

    1998-01-01

    In studies to determine the neurochemical mechanisms underlying adaptation to altered gravity we have investigated changes in neuropeptide levels in brainstem, cerebellum, hypothalamus, striatum, hippocampus, and cerebral cortex by radioimmunoassay. Fourteen days of hypergravity (hyperG) exposure resulted in significant increases in thyrotropin-releasing hormone (TRH) content of brainstem and cerebellum, but no changes in levels of other neuropeptides (beta-endorphin, cholecystokinin, met-enkephalin, somatostatin, and substance P) examined in these areas were found, nor were TRH levels significantly changed in any other brain regions investigated. The increase in TRH in brainstem and cerebellum was not seen in animals exposed only to the rotational component of centrifugation, suggesting that this increase was elicited by the alteration in the gravitational environment. The only other neuropeptide affected by chronic hyperG exposure was met-enkephalin, which was significantly decreased in the cerebral cortex. However, this alteration in met-enkephalin was found in both hyperG and rotation control animals and thus may be due to the rotational rather than the hyperG component of centrifugation. Thus it does not appear as if there is a generalized neuropeptide response to chronic hyperG following 2 weeks of exposure. Rather, there is an increase only of TRH and that occurs only in areas of the brain known to be heavily involved with vestibular inputs and motor control (both voluntary and autonomic). These results suggest that TRH may play a role in adaptation to altered gravity as it does in adaptation to altered vestibular input following labyrinthectomy, and in cerebellar and vestibular control of locomotion, as seen in studies of ataxia.

  8. Environmental heavy metal exposure and chronic kidney disease in the general population.

    Kim, Nam Hee; Hyun, Young Youl; Lee, Kyu-Beck; Chang, Yoosoo; Ryu, Seungho; Rhu, Seungho; Oh, Kook-Hwan; Ahn, Curie

    2015-03-01

    Lead (Pb), mercury (Hg), and cadmium (Cd) are common heavy metal toxins and cause toxicological renal effects at high levels, but the relevance of low-level environmental exposures in the general population is controversial. A total of 1,797 adults who participated in the KNHANES (a cross-sectional nationally representative survey in Korea) were examined, and 128 of them (7.1%) had chronic kidney disease (CKD). Our study assessed the association between Pb, Hg, Cd exposure, and CKD. Blood Pb and Cd levels were correlated with CKD in univariate logistic regression model. However, these environmental heavy metals were not associated with CKD after adjustment for age, sex, BMI, smoking, hyperlipidemia, hypertension, diabetes, and these metals in multivariate logistic regression models. We stratified the analysis according to hypertension or diabetes. In the adults with hypertension or diabetes, CKD had a significant association with elevated blood Cd after adjustment, but no association was present with blood Pb and Hg. The corresponding odds ratio [OR] of Cd for CKD were 1.52 (95% confidence interval [CI], 1.05-2.19, P=0.026) in adults with hypertension and 1.92 (95% CI, 1.14-3.25, P=0.014) in adults with diabetes. Environmental low level of Pb, Hg, Cd exposure in the general population was not associated with CKD. However, Cd exposure was associated with CKD, especially in adults with hypertension or diabetes. This finding suggests that environmental low Cd exposure may be a contributor to the risk of CKD in adults with hypertension or diabetes. PMID:25729249

  9. Metallothionein (MT) response after chronic palladium exposure in the zebra mussel, Dreissena polymorpha

    The effects of different exposure concentrations of palladium (Pd) on relative metallothionein (MT) response and bioaccumulation were investigated in zebra mussels (Dreissena polymorpha). The mussels were exposed to 0.05, 5, 50, and 500 μg/L Pd2+ for 10 weeks under controlled temperature and fasting conditions. Relative MT contents were assessed by a modified Ag-saturation method, which allows to discriminate between MT bound to Pd (Pd-MT) and MT bound to unidentified metals (Ag-MT). Determination of metal contents resulted from atomic absorption spectrometry following a microwave digestion. For unexposed mussels and mussels exposed to 0.05 μg/L Pd no metal accumulation could be detected. All other exposure concentrations resulted in detectable Pd accumulation in mussels with final tissue concentrations of 96 μg/g (500 μg/L), 45 μg/g (50 μg/L), and 9 μg/g (5 μg/L). Compared with initial levels Pd-MT concentrations at the end of the exposure period were 600 (500 μg/L), 160 (50 μg/L), and 27 (5 μg/L) times higher. These results show that an increase in MTs in D. polymorpha already occurs at relatively low aqueous Pd concentrations indicating that there is the need for detoxification of Pd in the mussel. Furthermore, correlations between Ag-MT and Pd accumulation indicate that higher exposure concentrations are associated with adverse effects on the mussels. Thus, harmful effects of chronic Pd exposure of organisms even in lowest concentrations cannot be excluded in the environment

  10. Chronic subhepatotoxic exposure to arsenic enhances hepatic injury caused by high fat diet in mice

    Arsenic is a ubiquitous contaminant in drinking water. Whereas arsenic can be directly hepatotoxic, the concentrations/doses required are generally higher than present in the US water supply. However, physiological/biochemical changes that are alone pathologically inert can enhance the hepatotoxic response to a subsequent stimulus. Such a ‘2-hit’ paradigm is best exemplified in chronic fatty liver diseases. Here, the hypothesis that low arsenic exposure sensitizes liver to hepatotoxicity in a mouse model of non-alcoholic fatty liver disease was tested. Accordingly, male C57Bl/6J mice were exposed to low fat diet (LFD; 13% calories as fat) or high fat diet (HFD; 42% calories as fat) and tap water or arsenic (4.9 ppm as sodium arsenite) for ten weeks. Biochemical and histologic indices of liver damage were determined. High fat diet (± arsenic) significantly increased body weight gain in mice compared with low-fat controls. HFD significantly increased liver to body weight ratios; this variable was unaffected by arsenic exposure. HFD caused steatohepatitis, as indicated by histological assessment and by increases in plasma ALT and AST. Although arsenic exposure had no effect on indices of liver damage in LFD-fed animals, it significantly increased the liver damage caused by HFD. This effect of arsenic correlated with enhanced inflammation and fibrin extracellular matrix (ECM) deposition. These data indicate that subhepatotoxic arsenic exposure enhances the toxicity of HFD. These results also suggest that arsenic exposure might be a risk factor for the development of fatty liver disease in human populations. -- Highlights: ► Characterizes a mouse model of arsenic enhanced NAFLD. ► Arsenic synergistically enhances experimental fatty liver disease at concentrations that cause no overt hepatotoxicity alone. ► This effect is associated with increased inflammation.

  11. Chronic Exposure to Bisphenol A Affects Uterine Function During Early Pregnancy in Mice.

    Li, Quanxi; Davila, Juanmahel; Kannan, Athilakshmi; Flaws, Jodi A; Bagchi, Milan K; Bagchi, Indrani C

    2016-05-01

    Environmental and occupational exposure to bisphenol A (BPA), a chemical widely used in polycarbonate plastics and epoxy resins, has received much attention in female reproductive health due to its widespread toxic effects. Although BPA has been linked to infertility and recurrent miscarriage in women, the impact of its exposure on uterine function during early pregnancy remains unclear. In this study, we addressed the effect of prolonged exposure to an environmental relevant dose of BPA on embryo implantation and establishment of pregnancy. Our studies revealed that treatment of mice with BPA led to improper endometrial epithelial and stromal functions thus affecting embryo implantation and establishment of pregnancy. Upon further analyses, we found that the expression of progesterone receptor (PGR) and its downstream target gene, HAND2 (heart and neural crest derivatives expressed 2), was markedly suppressed in BPA-exposed uterine tissues. Previous studies have shown that HAND2 controls embryo implantation by repressing fibroblast growth factor and the MAPK signaling pathways and inhibiting epithelial proliferation. Interestingly, we observed that down-regulation of PGR and HAND2 expression in uterine stroma upon BPA exposure was associated with enhanced activation of fibroblast growth factor and MAPK signaling in the epithelium, thus contributing to aberrant proliferation and lack of uterine receptivity. Further, the differentiation of endometrial stromal cells to decidual cells, an event critical for the establishment and maintenance of pregnancy, was severely compromised in response to BPA. In summary, our studies revealed that chronic exposure to BPA impairs PGR-HAND2 pathway and adversely affects implantation and the establishment of pregnancy. PMID:27022677

  12. Decision-making about chronic radiation exposure to the public. New recommendations from the ICRP

    The paper discusses decision-making in situations of chronic exposure within the framework of a forthcoming related ICRP report on the subject which has been produced by an ICRP Task Group chaired by the author. This ICRP report will provide guidance on the application of the ICRP System of Radiological Protection to prolonged exposure situations afflicting members of the public. It will address the general application of the System to the control of prolonged exposures resulting from practices and to the undertaking of interventions in prolonged exposure situations, and will provide recommendations on generic reference levels for such interventions. It will also consider some specific situations and will discuss a number of issues that have been of concern, namely: natural radiation sources that may give rise to high doses; the restoration and rehabilitation of sites where human activities involving radioactive substances have been carried out; the return to 'normality' following an accident that has released radioactive substances to the environment; and the global marketing of commodities for public consumption that contain relatively high levels of radioactive substances. Annexes will provide some examples of prolonged exposure situations and will discuss the radiological protection quantities, radiation-induced health effects and aspects of the System of Radiological Protection relevant to prolonged exposure. The quantitative recommendations for prolonged exposures provided in the report will be as follows: generic reference levels for intervention, in terms of existing annual doses, of < or approx. 100 mSv, above which intervention is almost always justifiable (situations for which the annual dose threshold for deterministic effects in relevant organs is exceeded will almost always require intervention), and of < or approx.10 mSv, below which intervention is not likely to be justifiable (and above which it may be necessary); intervention exemption levels for

  13. The Frequency of the Accidental Contamination with Laboratory Samples in Yazd Clinical Laboratories’ personnel in 2011

    Jafari, AA. (PhD

    2014-05-01

    Full Text Available Background and Objective: laboratory personnel have always accidental exposure to clinical samples, which can cause the transmission of infection. This threat can be prevented and controlled by education for the use of safety instruments. The purpose was to determine the frequency of accidental exposure to laboratory samples among Yazd laboratory personnel in 2011. Material and Methods: This descriptive cross-sectional study was conducted on 100 of Yazd clinical laboratory personnel. The data was collected, using a valid and reliable questioner, via interview and analyzed by means of SPSS software. Results: Eighty-six percent of the subjects reported an experience of accidental exposure to clinical samples, such as blood, serum and urine. The causes were carelessness (41% and work overload (29%. Needle- stick was the most prevalent injury (52% particularly in sampler workers (51% and in their hands (69%. There wasn’t significant relationship between accidental exposure to laboratory samples and the variables such as private and governmental laboratories (p=0.517, kind of employment (p=0.411, record of services (p=0.439 and academic degree (p=0.454. The subjects aged 20-29 (p=0.034 and worked in sampling unit had the highest accidental exposure. Conclusion: based on the results, inexperience of the personnel especially in sampling room, overload at work and ignorance of applying safety instruments are known as the most important reasons for accidental exposure to clinical samples. Keywords: Contamination; accidental Exposure; Infectious agents; laboratory; personnel

  14. Allegheny County Fatal Accidental Overdoses

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Fatal accidental overdose incidents in Allegheny County, denoting age, gender, race, drugs present, zip code of incident and zip code of residence. Zip code of...

  15. Chronic neonicotinoid pesticide exposure and parasite stress differentially affects learning in honeybees and bumblebees.

    Piiroinen, Saija; Goulson, Dave

    2016-04-13

    Learning and memory are crucial functions which enable insect pollinators to efficiently locate and extract floral rewards. Exposure to pesticides or infection by parasites may cause subtle but ecologically important changes in cognitive functions of pollinators. The potential interactive effects of these stressors on learning and memory have not yet been explored. Furthermore, sensitivity to stressors may differ between species, but few studies have compared responses in different species. Here, we show that chronic exposure to field-realistic levels of the neonicotinoid clothianidin impaired olfactory learning acquisition in honeybees, leading to potential impacts on colony fitness, but not in bumblebees. Infection by the microsporidian parasiteNosema ceranaeslightly impaired learning in honeybees, but no interactive effects were observed.Nosemadid not infect bumblebees (3% infection success). Nevertheless,Nosema-treated bumblebees had a slightly lower rate of learning than controls, but faster learning in combination with neonicotinoid exposure. This highlights the potential for complex interactive effects of stressors on learning. Our results underline that one cannot readily extrapolate findings from one bee species to others. This has important implications for regulatory risk assessments which generally use honeybees as a model for all bees. PMID:27053744

  16. Chronic toxicity of heavy fuel oils to fish embryos using multiple exposure scenarios.

    Martin, Jonathan D; Adams, Julie; Hollebone, Bruce; King, Thomas; Brown, R Stephen; Hodson, Peter V

    2014-03-01

    The chronic toxicity to rainbow trout (Oncorhynchus mykiss) embryos of heavy fuel oil (HFO) 6303, weathered HFO 6303, HFO 7102, and medium South American (MESA) crude oil was assessed by different exposure regimes. These included water accommodated fractions (WAF; water in contact with floating oil), chemically enhanced WAF (CEWAF; oil dispersed with Corexit 9500), and effluent from columns of gravel coated with stranded oil. Heavy fuel oil WAF was nontoxic and did not contain detectable concentrations of hydrocarbons, likely because the high density and viscosity of HFO prevented droplet formation. In contrast, chemically dispersed HFO and effluent from columns of stranded HFO contained measurable concentrations of alkyl polycyclic aromatic hydrocarbons (PAH), coincident with embryo toxicity. These exposure regimes enhanced the surface area of oil in contact with water, facilitating oil-water partitioning of hydrocarbons. Heavy fuel oil was consistently more toxic to fish than crude oil and the rank order of alkyl PAH concentrations in whole oil were sufficient to explain the rank order of toxicity, regardless of exposure method. Thus, the propensity of HFO to sink and strand in spawning shoals creates a long-term risk to developing fish because of the sustained release of PAHs from HFO to interstitial waters. Further, PAH monitoring is key to accurate risk assessment. PMID:24464524

  17. Histopathologic alterations associated with global gene expression due to chronic dietary TCDD exposure in juvenile zebrafish.

    Qing Liu

    Full Text Available The goal of this project was to investigate the effects and possible developmental disease implication of chronic dietary TCDD exposure on global gene expression anchored to histopathologic analysis in juvenile zebrafish by functional genomic, histopathologic and analytic chemistry methods. Specifically, juvenile zebrafish were fed Biodiet starter with TCDD added at 0, 0.1, 1, 10 and 100 ppb, and fish were sampled following 0, 7, 14, 28 and 42 d after initiation of the exposure. TCDD accumulated in a dose- and time-dependent manner and 100 ppb TCDD caused TCDD accumulation in female (15.49 ppb and male (18.04 ppb fish at 28 d post exposure. Dietary TCDD caused multiple lesions in liver, kidney, intestine and ovary of zebrafish and functional dysregulation such as depletion of glycogen in liver, retrobulbar edema, degeneration of nasal neurosensory epithelium, underdevelopment of intestine, and diminution in the fraction of ovarian follicles containing vitellogenic oocytes. Importantly, lesions in nasal epithelium and evidence of endocrine disruption based on alternatively spliced vasa transcripts are two novel and significant results of this study. Microarray gene expression analysis comparing vehicle control to dietary TCDD revealed dysregulated genes involved in pathways associated with cardiac necrosis/cell death, cardiac fibrosis, renal necrosis/cell death and liver necrosis/cell death. These baseline toxicological effects provide evidence for the potential mechanisms of developmental dysfunctions induced by TCDD and vasa as a biomarker for ovarian developmental disruption.

  18. Chronic exposure to neonicotinoids increases neuronal vulnerability to mitochondrial dysfunction in the bumblebee (Bombus terrestris).

    Moffat, Christopher; Pacheco, Joao Goncalves; Sharp, Sheila; Samson, Andrew J; Bollan, Karen A; Huang, Jeffrey; Buckland, Stephen T; Connolly, Christopher N

    2015-05-01

    The global decline in the abundance and diversity of insect pollinators could result from habitat loss, disease, and pesticide exposure. The contribution of the neonicotinoid insecticides (e.g., clothianidin and imidacloprid) to this decline is controversial, and key to understanding their risk is whether the astonishingly low levels found in the nectar and pollen of plants is sufficient to deliver neuroactive levels to their site of action: the bee brain. Here we show that bumblebees (Bombus terrestris audax) fed field levels [10 nM, 2.1 ppb (w/w)] of neonicotinoid accumulate between 4 and 10 nM in their brains within 3 days. Acute (minutes) exposure of cultured neurons to 10 nM clothianidin, but not imidacloprid, causes a nicotinic acetylcholine receptor-dependent rapid mitochondrial depolarization. However, a chronic (2 days) exposure to 1 nM imidacloprid leads to a receptor-dependent increased sensitivity to a normally innocuous level of acetylcholine, which now also causes rapid mitochondrial depolarization in neurons. Finally, colonies exposed to this level of imidacloprid show deficits in colony growth and nest condition compared with untreated colonies. These findings provide a mechanistic explanation for the poor navigation and foraging observed in neonicotinoid treated bumblebee colonies. PMID:25634958

  19. Kalrn promoter usage and isoform expression respond to chronic cocaine exposure

    Ma Xin-Ming

    2011-02-01

    Full Text Available Abstract Background The long-term effects of cocaine on behavior are accompanied by structural changes in excitatory glutamatergic synapses onto the medium spiny neurons of the striatum. The Kalrn gene encodes several functionally distinct isoforms; these multidomain guanine nucleotide exchange factors (GEFs contain additional domains known to interact with phosphatidylinositides as well as with a number of different proteins. Through their activation of Rho proteins and their interactions with other proteins, the different Kalirin isoforms affect cytoskeletal organization. Chronic exposure of adult male rodents to cocaine increases levels of Kalirin 7 in the striatum. When exposed chronically to cocaine, mice lacking Kalirin 7, the major adult isoform, fail to show an increase in dendritic spine density in the nucleus accumbens, show diminished place preference for cocaine, and exhibit increased locomotor activity in response to cocaine. Results The use of alternate promoters and 3'-terminal exons of the mouse Kalrn gene were investigated using real-time quantitative polymerase chain reaction. While the two most distal full-length Kalrn promoters are used equally in the prefrontal cortex, the more proximal of these promoters accounts for most of the transcripts expressed in the nucleus accumbens. The 3'-terminal exon unique to the Kalirin 7 isoform accounts for a greater percentage of the Kalrn transcripts in prefrontal cortex than in nucleus accumbens. Western blot analyses confirmed these differences. Chronic cocaine treatment increases usage of the promoter encoding the Δ-Kalirin isoforms but does not alter full-length Kalirin promoter usage. Usage of the 3'-terminal exon unique to Kalirin 7 increases following chronic cocaine exposure. Conclusions Kalrn promoter and 3'-terminal exon utilization are region-specific. In the nucleus accumbens, cocaine-mediated alterations in promoter usage and 3'-terminal exon usage favor expression of

  20. Chronic neonatal nicotine exposure increases excitation in the young adult rat hippocampus in a sex-dependent manner

    Damborsky, Joanne C.; Griffith, William H.; Ursula H Winzer-Serhan

    2011-01-01

    Smoking during pregnancy exposes the fetus to nicotine, resulting in nicotine-stimulated neurotransmitter release. Recent evidence suggests that the hippocampus develops differently in males and females with delayed maturation in males. We show that chronic nicotine exposure during the first postnatal week has sex-specific long-term effects. Neonatal rat pups were chronically treated with nicotine (6 mg/kg/day) (CNN) from postnatal day 1 to 7 or milk only (Controls), and hippocampal slices we...

  1. Long-term consequences of chronic fluoxetine exposure on the expression of myelination-related genes in the rat hippocampus.

    Kroeze, Y; Peeters, D; Boulle, F; van den Hove, D L A; van Bokhoven, H; Zhou, H; Homberg, J R

    2015-01-01

    The selective serotonin reuptake inhibitor (SSRI) fluoxetine is widely prescribed for the treatment of symptoms related to a variety of psychiatric disorders. After chronic SSRI treatment, some symptoms remediate on the long term, but the underlying mechanisms are not yet well understood. Here we studied the long-term consequences (40 days after treatment) of chronic fluoxetine exposure on genome-wide gene expression. During the treatment period, we measured body weight; and 1 week after treatment, cessation behavior in an SSRI-sensitive anxiety test was assessed. Gene expression was assessed in hippocampal tissue of adult rats using transcriptome analysis and several differentially expressed genes were validated in independent samples. Gene ontology analysis showed that upregulated genes induced by chronic fluoxetine exposure were significantly enriched for genes involved in myelination. We also investigated the expression of myelination-related genes in adult rats exposed to fluoxetine at early life and found two myelination-related genes (Transferrin (Tf) and Ciliary neurotrophic factor (Cntf)) that were downregulated by chronic fluoxetine exposure. Cntf, a neurotrophic factor involved in myelination, showed regulation in opposite direction in the adult versus neonatally fluoxetine-exposed groups. Expression of myelination-related genes correlated negatively with anxiety-like behavior in both adult and neonatally fluoxetine-exposed rats. In conclusion, our data reveal that chronic fluoxetine exposure causes on the long-term changes in expression of genes involved in myelination, a process that shapes brain connectivity and contributes to symptoms of psychiatric disorders. PMID:26393488

  2. Effects of Acute and Chronic Heavy Metal (Cu, Cd, and Zn) Exposure on Sea Cucumbers (Apostichopus japonicus)

    Li, Li; Tian, Xiangli; Yu, Xiao; Dong, Shuanglin

    2016-01-01

    Acute and chronic toxicity tests were conducted with sea cucumber (Apostichopus japonicus) exposed to heavy metals. Acute toxicity values (96 h LC50) were 2.697, 0.133, and 1.574 mg L−1 for Zn, Cu, and Cd, respectively, and were ranked in order of toxicity: Cu > Cd > Zn. Under chronic metal exposure the specific growth rates of sea cucumbers decreased with the increase of metal concentration for all the three metals. After acute metal exposure, the oxygen consumption rate (OCR) decreased. The...

  3. Assessing Cumulative Thermal Stress in Fish During Chronic Exposure to High Temperature

    Bevelhimer, M.S.; Bennett, W.R.

    1999-11-14

    As environmental laws become increasingly protective, and with possible future changes in global climate, thermal effects on aquatic resources are likely to receive increasing attention. Lethal temperatures for a variety of species have been determined for situations where temperatures rise rapidly resulting in lethal effects. However, less is known about the effects of chronic exposure to high (but not immediately lethal) temperatures and even less about stress accumulation during periods of fluctuating temperatures. In this paper we present a modeling framework for assessing cumulative thermal stress in fish. The model assumes that stress accumulation occurs above a threshold temperature at a rate depending on the degree to which the threshold is exceeded. The model also includes stress recovery (or alleviation) when temperatures drop below the threshold temperature as in systems with large daily variation. In addition to non-specific physiological stress, the model also simulates thermal effects on growth.

  4. [Influence of chronic lead exposure on resistence to bacterial infection (author's transl)].

    Ewers, U; Weisser, L; Wegner, A

    1980-01-01

    Suppression by lead of resistance to bacterial or viral infections has been reported by several authors. We have studied, if a decrease of resistance to bacterial infection could be evaluated at blood lead concentrations (PbB), which correspond to the upper levels of environmental or occupational lead exposure regarded as tolerable (PbB = 35 resp. 60 microgram/100 ml). NMRI mice were chronically exposed to lead by feeding with lead acetate containing diets and given a challenge with Salmonella typhimurium. No increase of susceptibility to bacterial infection could be demonstrated at PbB 100 microgram/100 g, however, an increase of lethality and a decrease of 50% survival times could be observed after bacterial infection. PMID:6999813

  5. Regional alterations of brain biogenic amines in young rats following chronic lead exposure

    Dubas, T.C.; Stevenson, A.; Singhal, R.L.; Hrdina, P.D.

    1978-02-01

    An examination was made of neurochemical changes that occur in discrete brain regions of rats that have been chronically exposed to low levels of lead from birth, in order to provide further information on the involvement of brain biogenic amines in lead-induced neurotoxicity. Results indicate a relationship between exposure to lead and alterations in the brain levels of various putative neurotransmitters. However, changes in the functional activity of the neurotransmitter may not be adequately reflected in the change of its steady-state levels or may occur even in the absence of any changes in the actual concentrations. Lead may influence central neurotransmitter function by affecting one or several of the processes involved in the synthesis, release and/or disposition of biogenic amines.

  6. Chronic estrogen exposure maintains elevated levels of progesterone receptor mRNA in guinea pig hypothalamus.

    Bayliss, D A; Millhorn, D E

    1991-05-01

    We performed in situ hybridization on hypothalamic sections from ovariectomized guinea pig using a cocktail of three 35S-labeled oligonucleotides complementary to mammalian progesterone receptor (PR) cDNA. PR mRNA was readily detected in hypothalamic neurons from guinea pigs pretreated with 17 beta-estradiol benzoate (E2B), but not from animals which did not receive supplemental E2B. The distribution of PR mRNA-containing cells corresponded well with previous localizations of PR in guinea pig. In contrast to earlier reports of E2B regulation of PR mRNA in rat hypothalamus, however, we found that PR mRNA remained elevated during chronic exposure to E2B (up to 10 days) in guinea pig. PMID:2072827

  7. Murine pulmonary responses after sub-chronic exposure to aluminum oxide-based nanowhiskers

    Adamcakova-Dodd Andrea

    2012-06-01

    Full Text Available Abstract Background Aluminum oxide-based nanowhiskers (AO nanowhiskers have been used in manufacturing processes as catalyst supports, flame retardants, adsorbents, or in ceramic, metal and plastic composite materials. They are classified as high aspect ratio nanomaterials. Our aim was to assess in vivo toxicity of inhaled AO nanowhisker aerosols. Methods Primary dimensions of AO nanowhiskers specified by manufacturer were 2–4 nm x 2800 nm. The aluminum content found in this nanomaterial was 30% [mixed phase material containing Al(OH3 and AlOOH]. Male mice (C57Bl/6 J were exposed to AO nanowhiskers for 4 hrs/day, 5 days/wk for 2 or 4 wks in a dynamic whole body exposure chamber. The whiskers were aerosolized with an acoustical dry aerosol generator that included a grounded metal elutriator and a venturi aspirator to enhance deagglomeration. Average concentration of aerosol in the chamber was 3.3 ± 0.6 mg/m3 and the mobility diameter was 150 ± 1.6 nm. Both groups of mice (2 or 4 wks exposure were necropsied immediately after the last exposure. Aluminum content in the lung, heart, liver, and spleen was determined. Pulmonary toxicity assessment was performed by evaluation of bronchoalveolar lavage (BAL fluid (enumeration of total and differential cells, total protein, activity of lactate dehydrogenase [LDH] and cytokines, blood (total and differential cell counts, lung histopathology and pulmonary mechanics. Results Following exposure, mean Al content of lungs was 0.25, 8.10 and 15.37 μg/g lung (dry wt respectively for sham, 2 wk and 4 wk exposure groups. The number of total cells and macrophages in BAL fluid was 2-times higher in animals exposed for 2 wks and 6-times higher in mice exposed for 4 wks, compared to shams (p p  Conclusions Sub-chronic inhalation exposures to aluminum-oxide based nanowhiskers induced increased lung macrophages, but no inflammatory or toxic responses were observed.

  8. Associations between Chronic Community Noise Exposure and Blood Pressure at Rest and during Acute Noise and Non-Noise Stressors among Urban School Children in India

    Bang Hyun Kim; Evans, Gary W.; Stephen J. Lepore; Bhaskar Shejwal

    2010-01-01

    The present study builds on prior research that has examined the association between children’s chronic exposure to community noise and resting blood pressure and blood pressure dysregulation during exposure to acute stressors. A novel contribution of the study is that it examines how chronic noise exposure relates to blood pressure responses during exposure to both noise and non-noise acute stressors. The acute noise stressor was recorded street noise and the non-noise stressor was mental ar...

  9. Chronic health effects of sulphur mustard exposure with special reference to Iranian veterans

    B Balali-Mood

    2008-01-01

    Full Text Available The widespread use of sulphur mustard (SM as an incapacitating chemical warfare agent in the past century has proved its long-lasting toxic effects. It may also be used as a chemical terrorist agent. Therefore, all health professionals should have sufficient knowledge and be prepared for any such chemical attack. SM exerts direct toxic effects on the eyes, skin, and respiratory tissue, with subsequent systemic action on the nervous, immunological, haematological, digestive, and reproductive systems. SM is an alkylating agent that affects DNA synthesis, and, thus, delayed complications have been seen since the First World War. Cases of malignancies in the target organs, particularly in haematopoietic, respiratory, and digestive systems, have been reported. Important delayed respiratory complications include chronic bronchitis, bronchiectasis, frequent bronchopneumonia, and pulmonary fibrosis, all of which tend to deteriorate with time. Severe dry skin, delayed keratitis, and reduction of natural killer cells with subsequent increased risk of infections and malignancies are also among the most distressing long-term consequences of SM intoxication. However, despite a lot of research over the past decades on Iranian veterans, there are still major gaps in the SM literature. Immunological and neurological dysfunction, as well as the relationship between SM exposure and mutagenicity, carcinogenicity, and teratogenicity are important fields that require further studies, particularly on Iranian veterans with chronic health effects of SM poisoning. There is also a paucity of information on the medical management of acute and delayed toxic effects of SM poisoning—a subject that greatly challenges health care specialists.

  10. Chronic Arsenic Exposure-Induced Oxidative Stress is Mediated by Decreased Mitochondrial Biogenesis in Rat Liver.

    Prakash, Chandra; Kumar, Vijay

    2016-09-01

    The present study was executed to study the effect of chronic arsenic exposure on generation of mitochondrial oxidative stress and biogenesis in rat liver. Chronic sodium arsenite treatment (25 ppm for 12 weeks) decreased mitochondrial complexes activity in rat liver. There was a decrease in mitochondrial superoxide dismutase (MnSOD) activity in arsenic-treated rats that might be responsible for increased protein and lipid oxidation as observed in our study. The messenger RNA (mRNA) expression of mitochondrial and nuclear-encoded subunits of complexes I (ND1 and ND2) and IV (COX I and COX IV) was downregulated in arsenic-treated rats only. The protein and mRNA expression of MnSOD was reduced suggesting increased mitochondrial oxidative damage after arsenic treatment. There was activation of Bax and caspase-3 followed by release of cytochrome c from mitochondria suggesting induction of apoptotic pathway under oxidative stress. The entire phenomenon was associated with decrease in mitochondrial biogenesis as evident by decreased protein and mRNA expression of nuclear respiratory factor 1 (NRF-1), nuclear respiratory factor 2 (NRF-2), peroxisome proliferator activator receptor gamma-coactivator 1α (PGC-1α), and mitochondrial transcription factor A (Tfam) in arsenic-treated rat liver. The results of the present study indicate that arsenic-induced mitochondrial oxidative stress is associated with decreased mitochondrial biogenesis in rat liver that may present one of the mechanisms for arsenic-induced hepatotoxicity. PMID:26767369

  11. Effect of head-only sub-chronic GSM exposure on spatial memory of rats

    Full text: Introduction: Low power electromagnetic fields (EMF) are suspected to produce deficit memory in rats. The study of Dubreuil et al (2003) showed that a short-term (10-15 days) exposure 'head-only' to GSM 900 MHz radio frequencies does not produce a deficit memory in adult rats. The aim of our experiment was to determine if head-only sub-chronic exposure (2 months) of rats to GSM signal for 45 min at a SAR = 1.5 W/Kg and for 15 min at 6 W/Kg induce deficit in spatial memory of rats in radial maze test. Materials and methods: Exposure system: Animals were placed in Plexiglas rockets with an individual loop antenna placed above the rat's head. Four animals were exposed at the time. Loop antennas were connected to a generator and emitted a GSM signal (900 MHz, pulsed at 217 Hz, 1/8 duty factor) 5 days / week for 8 weeks. Experimental group: 30 Sprague-Dawley male rats were randomly assigned to 5 different groups: a) 6 rats exposed 15 min at SAR = 6 W/Kg; b) 6 rats exposed 45 min at SAR = 1.5 W/g; c) 6 rats sham controls (3 for 5 min and 3 for 45 min, SAR = 0 W/Kg); d) 6 rats without any treatment and manipulation (cage control); e) 6 rats were injected (i.p) S.B.H 0.1 mg/Kg (Sigma Aldrich) as positive control group. Behavioural procedure: The radial maze protocol consists of two consecutive phases: the training task (10 days) and the test task (8 days). In the first phase, rats were trained to visit the 8 arms of the maze without returning to an arm already visited. In the second phase (8 days), a 45-min intra-trial delay was introduced after four visited arms. After the intra-delay, the rat was placed in the maze to finish the test task, which is visiting four other arms he had not visited. During the training task, exposure took place before the behavioural task. During the test task, exposure or sham-exposure took place during the intra-delay. Results and discussion: In all experiments, performance of exposed rats (1.5 and 6 W/Kg) was compared with that of

  12. Effects of chronic aluminum exposure on learning and memory and brain-derived nerve growth factor in rats

    潘宝龙

    2013-01-01

    Objective To investigate the effects of chronic aluminum exposure on the learning and memory abilities and brain-derived nerve growth factor (BDNF) in SpragueDawley (SD) rats.Methods Thirty-two male SD rats were randomly and equally divided into 4 groups:control group and high-,middle-,and low-dose exposure groups.The rats in high-,middle-,and low-dose expo-

  13. Chronic exposure to chlorpyrifos reveals two modes of action in the springtail Folsomia candida

    Organophosphates are popular insecticides, but relatively little is known about their chronic effects on ecologically relevant endpoints. In this paper, we examine a life-cycle experiment with the springtail Folsomia candida, exposed via food to chlorpyrifos (CPF). The results for all endpoints (survival, growth and reproduction) were analyzed using the DEBtox model. Growth was unaffected by CPF, even at concentrations causing severe effects on survival and reproduction. Model analysis suggests that CPF directly affects the process of egg production. For the short-term response (45 days), this single mode of action accurately agreed with the data. However, the full data set (120 days) revealed a dose-related decrease in reproduction at low concentrations after prolonged exposure, not covered by the same mechanism. It appears that CPF interacts with senescence by increasing oxidative damage. This assumption fits the data well, but has little consequences for the predicted response at the population level. - Exposure to chlorpyrifos in food affects reproduction in springtails according to two distinct toxic mechanisms

  14. Effects of depleted uranium chronic exposure on detoxification systems in vivo and in vitro

    Uranium (U) is a heavy metal naturally presents in the environment. The aim of this work is to study effects of a U exposure on organs involved in the detoxification: the kidney and the liver (and notably the xenobiotics metabolizing enzymes (XME)). In order to mimic population chronic exposure, rats were contaminated during 9 months through the drinking water (40 mg/L). In vivo results show that U, in our experimental conditions, does not induce neither nephrotoxicity nor sensitivity to increase a renal toxicity induced by gentamicin. In the liver, U provokes impairments on the XME gene expression, particularly CYP3A. Nevertheless, paracetamole metabolism is modified only if it is administrated at a hepatotoxic dose. The in vitro results suggest an indirect effect of uranium on the XME, probably dependant of body adaptation mechanisms. Besides, in vitro studies were underline cytotoxic properties of U as well as the localisation of its soluble and/or participated forms in cytoplasmic and nuclear compartment. (author)

  15. Chronic exposure to gamma radiation of wild populations of meadow voles (Microtus pennsylvanicus)

    Free-ranging, wild meadow voles (Microtus pennsylvanicus) were exposed to gamma radiation from a 137Cs irradiator in a series of experiments conducted on six 1-ha meadows within a mixed deciduous forest in Manitoba, Canada. Over a period of 1-1.5 years in each of three experiments, vole populations were monitored with capture-mark-release techniques at nominal exposure rates of 200x, 9000x and 40,000x background. No effects on population or individual characteristics were detected up to the highest exposure rate (81 mGy/d). At this level, third generation voles were monitored up to a lifetime dose of about 5.7 Gy, at a measured dose rate of 44 mGy/d. Smaller numbers of overwintered animals survived and reproduced normally at doses up to 10 Gy. These results are discussed in terms of low-LET, external chronic radiation effects on rodents in the laboratory and the field, relative to current views on appropriate benchmarks for the protection of biota

  16. Effects of long-term chronic exposure to radionuclides in plant populations

    The results of field studies carried out on different plant species (winter rye and wheat, spring barley, oats, Scots pine, wild vetch, crested hairgrass) in various radioecological situations (nuclear weapon testing, the Chernobyl accident, uranium and radium processing) to investigate the effects of long-term chronic exposure to radionuclides are discussed. Plant populations growing in areas with relatively low levels of pollution are characterized by an increased level of both cytogenetic disturbances and genetic diversity. Although ionizing radiation causes primary damage at the molecular level, there are emergent effects at the level of populations, non-predictable from the knowledge of elementary mechanisms of cellular effects formation. Accumulation of cellular alterations may afterward influence biological parameters important for populations such as health and reproduction. Presented data provide evidence that in plant populations inhabiting heavily contaminated territories cytogenetic damage could be accompanied by a decrease in reproductive capacity. However, in less contaminated sites, because of the scarcity of data available, a steady relationship between cytogenetic effects and reproductive capacity was not revealed. Under radioactive contamination of the plant's environment, a population's resistance to exposure may increase. However, there are radioecological situations where an enhanced radioresistance has not evolved or has not persisted

  17. Nuclear toxicology file: ecological consequences of a chronic exposure to uranium

    This article presents the thought process and the current developments, based on the experimental acquisition of the answers of the alive organisms to the chronic low dose exposures of natural uranium in fresh water, to identify the consequences of this exposure on the populations composing the ecosystems. The results acquired on the zebra fish (Danio rerio) show an impact on the first steps of development. We note a delay of hatching upon 40 % from 20 μg/l of uranium. This delay comes along with a decrease of the size and with a reduction of the growth of larvas as well as with an increase of their mortality for higher uranium concentration. For adults exposed to uranium a decrease of reproduction success is observed from a concentration of 20μg/l. The consequences in term of fertility (total number of laid roes) are drastic, with a reduction of a factor 2 and 60, for the organisms exposed respectively to 20 and 250 μg/l of uranium. A study was also made on several generations (populations of benthic invertebrates), it suggests an adaptation (genetic selection) but created a bigger fragility to a new environment even identical to their environment of origin with notably a decrease of the reproduction. (N.C.)

  18. Response of tibialis anterior tendon to a chronic exposure of stretch-shortening cycles: age effects

    Baker Brent B

    2009-06-01

    Full Text Available Abstract Background The purpose of the current study was to investigate the effects of aging on tendon response to repetitive exposures of stretch-shortening cycles (SSC's. Methods The left hind limb from young (3 mo, N = 4 and old (30 mo, N = 9 male Fisher 344 × Brown Norway rats were exposed to 80 maximal SSCs (60 deg/s, 50 deg range of motion 3x/week for 4.5 weeks in vivo. After the last exposure, tendons from the tibialis anterior muscle were isolated, stored at -80°C, and then tested using a micro-mechanical testing machine. Deformation of each tendon was evaluated using both relative grip-to-grip displacements and reference marks via a video system. Results At failure, the young control tendons had higher strain magnitude than the young exposed (p Conclusion The chronic protocol enhanced the elastic stiffness of young tendon and the loads in both the young and old tendons. The old exposed tendons were found to exhibit higher load capacity than their younger counterparts, which differed from our initial hypothesis.

  19. [MORPHOFUNCTIONAL STATE OF BLOOD CELLS AFTER CHRONIC EXPOSURE OF THE PROTEIN KINASES INHIBITOR MALEIMIDE DERIVATIVE].

    Byelinska, I V; Lynchak, O V; Tsyvinska, S M; Rybalchenko, V K

    2015-01-01

    The effect of the protein kinases inhibitor maleimide derivative (MI-1, 1-(4-Cl-benzyl)-3-Cl-4-(CF3-phenylamino)-1H-pyrrole-2,5-dione), inhibitor of VEGF-R1,2,3, FGF-R1, EGF-R(h), PDK1, Src(h), Syk(h), YES, ZAP70 et al. with antineoplastic activity, on blood cells parameters of rats after chronic exposure has been studied. Administration of MI-1 at doses 0.027 and 2.7 mg/kg (suppress colon carcinogenesis) for 20 and 26 weeks does not affect the morphofunctional state of red blood cells in healthy rats. This is confirmed by the lack of differences in the concentration of hemoglobin in blood, red blood cells count, mean corpuscular hemoglobin and mean corpuscular hemoglobin concentration, hematocrit and mean corpuscular volume, and the number of reticulocytes in blood after 20 and 26 weeks of exposure compared with the control group. MI-1 at indicated doses does not influence total leukocytes count and content (eosinophilic and neutrophilic granulocytes, lymphocytes, monocytes) and does not inhibit thrombocytopoiesis (platelet count remains unchanged). No negative effect of MI-1 on hematopoiesis is not limited (by the hemopoietic system) use of this compound as a potential antitumor drug PMID:26552308

  20. Effects of Sub-chronic Aluminum Exposure on Renal Structure in Rats

    Li Yan-fei; Liu Jian-yu; Cao Zheng

    2015-01-01

    To investigate the effects of aluminum (Al) exposure on renal structure of rats, 60 Wistar rats were randomly divided into four treatment groups and were orally exposed to 0 (control group, GC), 64.18 (low-dose group, GL), 128.36 (middle-dose group, GM), and 256.72 (high-dose group, GH) mg• kg-1 BW AlCl3 in drinking water for 120 days. The body weight of different rats was recorded, the kidney pathologic structure and the ultrastructure were observed. The results showed that the body weight of different rats was markedly lower in Al-treated rats than those in GC (P<0.05;P<0.01). After masson staining, the collagen was deposited in the renal interstitium and aggravated with Al dose increases in Al-treated rats. Under electron microscope, the infolding of the plasma membrane was slight swollen, the mitochondrion was abundant with different sizes, the mitochondrion cristae was fused, the microvillus was swollen and fused in GH. Our findings indicated that sub-chronic Al exposure slowed the weight of rats and caused the kidney pathologic damage in rats.

  1. The reproductive effects in rats after chronic oral exposure to low-dose depleted uranium

    This two-generation study evaluated the effects of depleted uranium (DU) on reproduction in rats. Across two generations, Wistar rats (30/sex/group) were maintained on feed containing DU at dose levels of 0 (control group), 4 (DU4 group), or 40 (DU40 group) mg kg-1 day-1 for 4 months prior to mating. After 4 months of exposure, the pregnancy rate, normal labour rate, and survival rate of offspring produced by F1 rats were all significantly decreased as compared to the control group, and especially in the DU40 group, these parameters fell by half to two-thirds, while no adverse effects were evident in F0 rats. The uranium content in the testes and ovaries of F1 rats in the DU4 and DU40 groups was significantly higher than that found in F0 rats. The levels of sex hormone in the serum were disorder in both generations. The enzymes related to spermiogenesis were also significantly different between generations, and the damage was more severe in F1 rats. In conclusion, the reproductive effects in F0 rats were slight after chronic oral exposure to DU, while the effects were obvious in F1 rats. (author)

  2. Pulmonary and hepatic injury after sub-chronic exposure to sublethal doses of microcystin-LR.

    Carvalho, Giovanna Marcella Cavalcante; Oliveira, Vinícius Rosa; Casquilho, Natália Vasconcelos; Araujo, Andressa Cristine Pereira; Soares, Raquel Moraes; Azevedo, Sandra Maria F O; Pires, Karla Maria Pereira; Valença, Samuel Santos; Zin, Walter Araujo

    2016-03-15

    We had previously shown that microcystin-LR (MCLR) could induce lung and liver inflammation after acute exposure. The biological outcomes following prolonged exposure to MCLR, although more frequent, are still poorly understood. Thus, we aimed to verify whether repeated doses of MCLR could damage lung and liver and evaluate the dose-dependence of the results. Male Swiss mice received 10 intraperitoneal injections (i.p.) of distilled water (60 μL, CTRL) or different doses of MCLR (5 μg/kg, TOX5), 10 μg/kg (TOX10), 15 μg/kg (TOX15) and 20 μg/kg (TOX20) every other day. On the tenth injection respiratory mechanics (lung resistive and viscoelastic/inhomogeneous pressures, static elastance, and viscoelastic component of elastance) was measured. Lungs and liver were prepared for histology (morphometry and cellularity) and inflammatory mediators (KC and MIP-2) determination. All mechanical parameters and alveolar collapse were significantly higher in TOX5, 10, 15 and 20 than CTRL, but did not differ among them. Lung inflammatory cell content increased dose-dependently in all TOX groups in relation to CTRL, being TOX20 the largest. The production of KC was increased in lung and liver homogenates. MIP-2 increased in the liver of all TOX groups, but in lung homogenates it was significantly higher only in TOX20 group. All TOX mice livers showed steatosis, necrosis, inflammatory foci and a high degree of binucleated hepatocytes. In conclusion, sub-chronic exposure to MCLR damaged lung and liver in all doses, with a more important lung inflammation in TOX20 group. PMID:26844922

  3. Chronic exposure to low-levels of lead in the rat: biochemical and behavioural changes

    The prevalence of lead in the environment is a cause of continuing toxicology concern and there have been numerous human and animal studies to examine more thoroughly the possible consequences of exposure to this ecotoxicant. Because lead is highly toxic to the developing central nervous system, increasing concern over the rise in the lead content in the environment has been expressed. These concerns seem appropriate since more recent clinical studies have shown that prolonged exposure of children to so called 'subclinical' concentrations of lead may be associated with behavioural disorders, learning disabilities and mental retardation. Moreover, animal studies have shown that chronic perinatal low-level lead exposure elicits alterations in both learned and spontaneous behavioural patterns in the absence of typical outward signs of lead-induced neurological toxicity. No study however could relate behavioural changes to specific alterations in neurochemisty. The aim of this study was therefore to expose rats, in different stages of their development, to low-levels of lead in order to induce behavioural disorders and correlate latter with possible neurochemical changes. In accordance with the general aims of the study, the structuring of the thesis is as follows: (a) a discussion of the neurotransmitters in the brain in order to describe the different systems which have been investigated; (b) a review of appropriate literature regarding the kinetics, toxodynamics and neurotoxicity of lead and (c) a summary of the methods employed in the study. The following results are presented: (d) the effects of lead treatment on physical development of the rats; (e) the induction of behavioural supersensitivity and (f) the effects lead has on central receptors

  4. Immunological changes of chronic oral exposure to depleted uranium in mice.

    Hao, Yuhui; Ren, Jiong; Liu, Jing; Yang, Zhangyou; Liu, Cong; Li, Rong; Su, Yongping

    2013-07-01

    Direct ingestion of contaminated soil by depleted uranium (DU) might lead to internal exposure to DU by local populations through hand contamination. The purpose of this study was to assess the immunological changes of long-term exposure to various doses of DU in mice. Three-week-old Kunming mice were divided into the following 4 groups based on the various feeding doses (containing DU): 0 (control group), 3 (DU3 group), 30 (DU30 group), and 300 mg/kg feed (DU300 group). After 4 months of exposure, in the DU300 group, the innate immune function decreased, manifesting as decreased secretion of nitric oxide, interleukin (IL)-1β, IL-18, and tumour necrosis factor (TNF)-α in the peritoneal macrophages, as well as reduced cytotoxicity of the splenic natural killer cells. Moreover, the cellular and humoral immune functions were abnormal, as manifested by decreased proliferation of the splenic T cells, proportion of the cluster of differentiation (CD) 3(+) cells, ratio of CD4(+)/CD8(+) cells and delayed-type hypersensitivity, and increased proliferation of the splenic B cells, total serum immunoglobin (Ig) G and IgE, and proportion of splenic mIgM(+)mIgD(+) cells. Through stimulation, the secretion levels of interferon (IFN)-γ and TNF-α in the splenic cells were reduced, and the levels of IL-4 and IL-10 were increased. By comparison, in the DU30 and DU3 groups, the effects were either minor or indiscernible. In conclusions, chronic intake of higher doses of DU (300 mg/kg) had a significant impact on the immune function, most likely due to an imbalance in T helper (Th) 1 and Th2 cytokines. PMID:23659960

  5. Quantitative Neuropathology Associated with Chronic Manganese Exposure in South African Mine Workers

    Gonzalez-Cuyar, Luis F.; Nelson, Gill; Criswell, Susan R.; Ho, Pokuan; Lonzanida, Jaymes A.; Checkoway, Harvey; Seixas, Noah; Gelman, Benjamin B.; Evanoff, Bradley A.; Murray, Jill; Zhang, Jing; Racette, Brad A.

    2014-01-01

    Manganese (Mn) is a common neurotoxicant associated with a clinical syndrome that includes signs and symptoms referable to the basal ganglia. Despite many advances in understanding the pathophysiology of Mn neurotoxicity in humans, with molecular and structural imaging techniques, only a few case reports describe the associated pathological findings, and all are in symptomatic subjects exposed to relatively high-level Mn. We performed an exploratory, neurohistopathological study to investigate the changes in the corpus striatum (caudate nucleus, putamen, and globus pallidus) associated with chronic low-level Mn exposure in South African Mn mine workers. Immunohistochemical techniques were used to quantify cell density of neuronal and glial components of the corpus striatum in eight South African Mn mine workers without clinical evidence of a movement disorder and eight age-race-gender matched, non-Mn mine workers. There was higher mean microglia density in Mn mine workers than non-Mn mine workers in the globus pallidus external and internal segments [GPe: 1.33 and 0.87 cells per HPF, respectively (p=0.064); GPi: 1.37 and 0.99 cells per HPF, respectively (p=0.250)]. The number of years worked in the Mn mines was significantly correlated with microglial density in the GPi (Spearman's rho 0.886; p=0.019). The ratio of astrocytes to microglia in each brain region was lower in the Mn mine workers than the non-Mn mine workers in the caudate (7.80 and 14.68; p=0.025), putamen (7.35 and 11.11; p=0.117), GPe (10.60 and 16.10; p=0.091) and GPi (9.56 and 12.42; p=0.376). Future studies incorporating more detailed occupational exposures in a larger sample of Mn mine workers will be needed to demonstrate an etiologic relationship between Mn exposure and these pathological findings. PMID:24374477

  6. Effects of chronic exposure to ionising radiation in the Pacific oyster Crassostrea gigas

    The Cotentin peninsula (Normandy, France) hosts nuclear industry facilities which operate with controlled discharges of radionuclides in the marine environment. Compared to natural radioactivity, the increase by artificial radionuclides is small but constant. As a consequence, marine species are chronically exposed to low additional doses of ionizing radiation (IR). The effects of chronic exposure to radionuclides were investigated in early stages of development of the Japanese oyster Crassostrea gigas. On the basis of literature, mollusks are expected to be particularly resistant to acute IR (UNSCEAR, 1996. Sources and effects of ionizing radiation. Report to the General Assembly, with Scientific Annex. 86 p). Two different chronic exposure conditions consisted in external (137Cs) and internal (241Am) irradiation for two weeks. Biological endpoints were analyzed in parallel at both the integrated (growth) and molecular (target stress gene expression) levels. To identify potential biological targets of IR, oysters were first exposed to very high dose rates and radionuclide activities with the perspective to reduce the levels and to derive dose-response curves. Although the initial exposure levels (137Cs 30 000 μGy.h-1; 241Am 57 000 Bq.L-1) were many orders of magnitude higher than those encountered in the natural environment, no significant change in the measured parameters was observed. This result was surprising because data from the literature showed that exposure of mussel Mytilus edulis to 3H at lower doses rates (10-100 μGy.h-1) induced DNA damage in hemocytes (Jha et al., 2005. Impact of low doses of tritium on the marine mussel, Mytilus edulis: Genotoxic effects and tissue-specific bioconcentration. Mutation Research/Genetic Toxicology and Environmental Mutagenesis 586, 47-57). To understand this apparent discrepancy between those two filtering bivalves, a new experiment was performed to compare the response of oyster exposed to 3H in the same condition

  7. Effects of chronic exposure to ionising radiation in the Pacific oyster Crassostrea gigas

    Fievet, B.; Devos, A.; Voiseux, C.; Leconte-Pradines, C. [Institut de Radioprotection et de Surete' Nucleaire (France); Dallas, L.; Jha, A. [University of Plymouth (United Kingdom)

    2014-07-01

    The Cotentin peninsula (Normandy, France) hosts nuclear industry facilities which operate with controlled discharges of radionuclides in the marine environment. Compared to natural radioactivity, the increase by artificial radionuclides is small but constant. As a consequence, marine species are chronically exposed to low additional doses of ionizing radiation (IR). The effects of chronic exposure to radionuclides were investigated in early stages of development of the Japanese oyster Crassostrea gigas. On the basis of literature, mollusks are expected to be particularly resistant to acute IR (UNSCEAR, 1996. Sources and effects of ionizing radiation. Report to the General Assembly, with Scientific Annex. 86 p). Two different chronic exposure conditions consisted in external ({sup 137}Cs) and internal ({sup 241}Am) irradiation for two weeks. Biological endpoints were analyzed in parallel at both the integrated (growth) and molecular (target stress gene expression) levels. To identify potential biological targets of IR, oysters were first exposed to very high dose rates and radionuclide activities with the perspective to reduce the levels and to derive dose-response curves. Although the initial exposure levels ({sup 137}Cs 30 000 μGy.h{sup -1}; {sup 241}Am 57 000 Bq.L{sup -1}) were many orders of magnitude higher than those encountered in the natural environment, no significant change in the measured parameters was observed. This result was surprising because data from the literature showed that exposure of mussel Mytilus edulis to {sup 3}H at lower doses rates (10-100 μGy.h{sup -1}) induced DNA damage in hemocytes (Jha et al., 2005. Impact of low doses of tritium on the marine mussel, Mytilus edulis: Genotoxic effects and tissue-specific bioconcentration. Mutation Research/Genetic Toxicology and Environmental Mutagenesis 586, 47-57). To understand this apparent discrepancy between those two filtering bivalves, a new experiment was performed to compare the response

  8. Accidental inhalation of mercury vapour: respiratory and toxicologic consequences.

    Lien, D. C.; Todoruk, D. N.; Rajani, H. R.; Cook, D A; Herbert, F. A.

    1983-01-01

    Four adults, including a pregnant woman, and three children were admitted to hospital following accidental exposure to mercury vapour produced by heating mercury-gold amalgam. Initial symptoms and signs included a paroxysmal cough, dyspnea, chest pain, tachypnea, nausea, vomiting, fever and leukocytosis. Pulmonary function testing performed on the second day after exposure revealed air-flow obstruction and minor restrictive defects in three patients. The diffusing capacity of the lung for car...

  9. A novel mouse model for the study of the inhibitory effects of chronic ethanol exposure on direct bone formation

    Excessive alcohol consumption has been reported to interfere with human bone homeostasis and repair in multiple ways. Previous studies have demonstrated that chronic ethanol exposure in the rat via an intragastric dietary delivery system inhibits direct bone formation during distraction osteogenesis...

  10. HEALTH RISKS FROM CHRONIC EXPOSURE TO ARSENIC VIA DRINKING WATER: FINDINGS FROM THE CLINICAL INVESTIGATIONS DATA IN INNER MONGOLIA, CHINA

    Prior studies have reported a large number of arsenicism cases in the Mongolia Autonomous Region of China due to drinking arsenic-contaminated water with concentrations up to 1.8 mg/L. However, the endemic health risks from chronic exposure to arsenic in this population have not...

  11. Chronic ethanol exposure downregulates hepatic expression of pregnane X receptor and P450 3A11 in female ICR mice

    Pregnane X receptor (PXR) is a nuclear receptor that regulates cytochrome P450 3A (CYP3A) gene transcription in a ligand-dependent manner. Ethanol has been reported to be either an inducer or an inhibitor of CYP3A expression. In this study, we investigated the effects of chronic ethanol exposure on PXR and P450 3A11 gene expression in mouse liver. Female ICR mice were administered by gavage with different doses (1000, 2000 and 4000 mg/kg) of ethanol for up to 5 weeks. Hepatic PXR and P450 3A11 mRNA levels were measured using RT-PCR. Erythromycin N-demethylase (ERND) activity was used as an indicator of CYP3A protein expression. Results showed that chronic ethanol exposure markedly decreased hepatic PXR and P450 3A11 mRNA levels. Consistent with downregulation of P450 3A11 mRNA, chronic ethanol exposure significantly decreased ERND activity in a dose-dependent manner. Additional experiment showed that chronic ethanol exposure significantly increased plasma endotoxin level and hepatic CD14 and TLR-4 mRNA expression, all of which were blocked by elimination of Gram-negative bacteria and endotoxin with antibiotics. Correspondingly, pretreatment with antibiotics reversed the downregulation of PXR and P450 3A11 mRNA expression and ERND activity in mouse liver. Furthermore, the downregulation of hepatic PXR and P450 3A11 mRNA expression was significantly attenuated in mice pretreated with GdCl3, a selective Kupffer cell toxicant. GdCl3 pretreatment also significantly attenuated chronically ethanol-induced decrease in ERND activity. These results indicated that activation of Kupffer cells by gut-derived endotoxin contributes to downregulation of hepatic PXR and P450 3A11 expression during chronic alcohol intoxication

  12. Review of the chronic exposure pathways models in MACCS [MELCOR Accident Consequence Code System] and several other well-known probabilistic risk assessment models

    The purpose of this report is to document the results of the work performed by the author in connection with the following task, performed for US Nuclear Regulatory Commission, (USNRC) Office of Nuclear Regulatory Research, Division of Systems Research: MACCS Chronic Exposure Pathway Models: Review the chronic exposure pathway models implemented in the MELCOR Accident Consequence Code System (MACCS) and compare those models to the chronic exposure pathway models implemented in similar codes developed in countries that are members of the OECD. The chronic exposures concerned are via: the terrestrial food pathways, the water pathways, the long-term groundshine pathway, and the inhalation of resuspended radionuclides pathway. The USNRC has indicated during discussions of the task that the major effort should be spent on the terrestrial food pathways. There is one chapter for each of the categories of chronic exposure pathways listed above

  13. Tissue-specific Bio-accumulation of Metals in Fish during Chronic Waterborne and Dietary Exposures

    M. Javed

    2012-10-01

    Full Text Available Juvenile (120-day three fish species viz. Catla catla, Labeo rohita and Cirrhina mrigala were exposed to chronic sub-lethal concentrations (1/3rd of LC50/LD50 of waterborne and dietary copper (Cu, cadmium (Cd, zinc (Zn, nickel (Ni and cobalt (Co, separately, in glass aquaria under constant water temperature (29oC, pH (7.5 and hardness (225 mgL-1 for 12 weeks. Waterborne and dietary exposures caused significantly variable accumulation of metals in three fish species that followed Zn>Ni>Cd>Co>Cu. Fish liver showed significantly higher tendency to accumulate Cu (69.64±25.35 µg g-1, Cd (68.93±21.65 µg g-1, Zn (91.46±29.53 µg g-1, Ni (74.64±18.61 µg g-1 and Co (22.65±20.56 µg g-1, followed by that of kidney and gills, with significant differences while muscle and bones exhibited significantly least tendency to accumulate all metals. Labeo rohita (31.63±2.43 µg g-1 and C. mrigala (31.43±13.70 µg g-1 exhibited significantly higher ability to amass metals than that of C. catla (27.96±10.28 µg g-1. Waterborne exposure caused significantly higher accumulation of metals in fish liver (72.69±27.91 µg g-1, followed by that in kidney, gills, skin, muscle, fins and bones with the average concentrations of 45.14±18.70, 39.47±21.13, 30.81±12.64, 22.65±17.34, 22.23±11.74 and 12.14±6.25 µg g-1, respectively. Dietary exposure resulted into significant escalation of metals in fish liver (58.23±32.44 µg g-1 while it was lowest in bones. Waterborne exposure caused significantly higher accumulation of all metals in fish body than that of dietary treatments.

  14. Dust exposure and chronic respiratory symptoms among coffee curing workers in Kilimanjaro: a cross sectional study

    Sakwari Gloria

    2011-11-01

    Full Text Available Abstract Background Coffee processing causes organic dust exposure which may lead to development of respiratory symptoms. Previous studies have mainly focused on workers involved in roasting coffee in importing countries. This study was carried out to determine total dust exposure and respiratory health of workers in Tanzanian primary coffee-processing factories. Methods A cross sectional study was conducted among 79 workers in two coffee factories, and among 73 control workers in a beverage factory. Personal samples of total dust (n = 45 from the coffee factories and n = 19 from the control factory were collected throughout the working shift from the breathing zone of the workers. A questionnaire with modified questions from the American Thoracic Society questionnaire was used to assess chronic respiratory symptoms. Differences between groups were tested by using independent t-tests and Chi square tests. Poisson Regression Model was used to estimate prevalence ratio, adjusting for age, smoking, presence of previous lung diseases and years worked in dusty factories. Results All participants were male. The coffee workers had a mean age of 40 years and were older than the controls (31 years. Personal total dust exposure in the coffee factories were significantly higher than in the control factory (geometric mean (GM 1.23 mg/m3, geometric standard deviation (GSD (0.8 vs. 0.21(2.4 mg/m3. Coffee workers had significantly higher prevalence than controls for cough with sputum (23% vs. 10%; Prevalence ratio (PR; 2.5, 95% CI 1.0 - 5.9 and chest tightness (27% vs. 13%; PR; 2.4, 95% CI 1.1 - 5.2. The prevalence of morning cough, cough with and without sputum for 4 days or more in a week was also higher among coffee workers than among controls. However, these differences were not statistically significant. Conclusion Workers exposed to coffee dust reported more respiratory symptoms than did the controls. This might relate to their exposure to coffee dust

  15. Accidental degeneracies in string compactification

    Bais, F.A.; Taormina, A.

    1986-11-27

    The equivalence of the torus and group manifold compactification of strings is established. Accidental degeneracies are shown to occur for a large class of compactifications. This way many examples are obtained in which modular invariance does not uniquely fix the representation content of the spectrum.

  16. Accidental degeneracies in string compactification

    Bais, F. A.; Taormina, A.

    1986-11-01

    The equivalence of the torus and group manifold compactification of strings is established. Accidental degeneracies are shown to occur for a large class of compactifications. This way many examples are obtained in which modular invariance does not uniquely fix the representation content of the spectrum.

  17. Accidente de Trabajo y Recargo

    Pérez Alonso, María Antonia

    2015-01-01

    En la actualidad existen diferentes formas de Accidente de Trabajo. En el presente trabajo se da a conocer las distintas formas y la doctrina de los tribunales. Se aborda el recargo de prestaciones de Seguridad Social y el deber del empresario en cumplir la normativa de Seguridad Social

  18. Medical management of accidentally exposed individuals

    Bone marrow aplasia is one of the main syndromes following a high dose accidental radiation exposure. Whilst transfusion and bone marrow transplantation have been used with some success starting with the first treatments of accident victims, other therapeutic strategies are needed. With the development of experimental and clinical haematology, promising new approaches to the treatment of aplasia have appeared. New trends for the treatment of haemopoietic injury based on bone marrow transplantation rely on new sources of compatible donor cells, such as cord blood, on the selection of immature haemopoietic cells and on new transplant regimens. Haemopoietic growth factors stimulate the proliferation and/or differentiation of haemopoietic progenitors and, possibly, stem cells. Furthermore, they act on the functions of mature cells. Currently, they have specific uses in haematology related to their role in the regulation of growth and in the differentiation of haemopoietic progenitor cells. Growth factors have already been used for the treatment of accidental radiation induced aplasia and lessons have been learned from their medical management and followup. (author)

  19. Medical management of accidentally exposed individuals

    Bone marrow aplasia is one of the main syndromes following a high dose accidental radiation exposure. Although both transfusion and bone marrow transplantation have been used with some success since the first treatments of patients, other therapeutic strategies are needed. New promising approaches of the treatment of aplasia have appeared with the development of experimental and clinical hematology. Some new trends for the treatment of the hematopoietic injury based on bone marrow transplantation rely on new sources of compatible donor cells, such as cord blood, on the selection of immature haemopoietic cells and on new transplant regimens. The hematopoietic growth factors stimulate proliferation and/or differentiation of hematopoietic progenitors and possibly stem cells. Furthermore, they act on the functions of mature cells. They have now specific uses in hematology, related to their role in the regulation of growth and differentiation of hematopoietic progenitor cells. Some growth factors have already been used for the treatment of accidental radiation-induced aplasia and lessons have been learned from their medical management and follow-up. (author)

  20. Accidental radioisotope burns - Management of late sequelae

    Varghese Bipin

    2010-10-01

    Full Text Available Accidental radioisotope burns are rare. The major components of radiation injury are burns, interstitial pneumonitis, acute bone marrow suppression, acute renal failure and adult respiratory distress syndrome. Radiation burns, though localized in distribution, have systemic effects, and can be extremely difficult to heal, even after multiple surgeries. In a 25 year old male who sustained such trauma by accidental industrial exposure to Iridium192 the early presentation involved recurrent haematemesis, pancytopenia and bone marrow suppression. After three weeks he developed burns in contact areas in the left hand, left side of the chest, abdomen and right inguinal region. All except the inguinal wound healed spontaneously but the former became a non-healing ulcer. Pancytopenia and bone marrow depression followed. He was treated with morphine and NSAIDs, epidural buprinorphine and bupivicaine for pain relief, steroids, antibiotics followed by wound excision and reconstruction with tensor fascia lata(TFL flap. Patient had breakdown of abdominal scar later and it was excised with 0.5 cm margins up to the underlying muscle and the wound was covered by a latissimis dorsi flap. Further scar break down and recurrent ulcers occurred at different sites including left wrist, left thumb and right heel in the next two years which needed multiple surgical interventions.

  1. Chronic cocaine or ethanol exposure during adolescence alters novelty-related behaviors in adulthood.

    Stansfield, Kirstie H; Kirstein, Cheryl L

    2007-04-01

    Adolescence is a time of high-risk behavior and increased exploration. This developmental period is marked by a greater probability to initiate drug use and is associated with an increased risk to develop addiction and adulthood dependency and drug use at this time is associated with an increased risk. Human adolescents are predisposed toward an increased likelihood of risk-taking behaviors [Zuckerman M. Sensation seeking and the endogenous deficit theory of drug abuse. NIDA Res Monogr 1986;74:59-70.], including drug use or initiation. In the present study, adolescent animals were exposed to twenty days of either saline (0.9% sodium chloride), cocaine (20 mg/kg) or ethanol (1 g/kg) i.p. followed by a fifteen-day washout period. All animals were tested as adults on several behavioral measures including locomotor activity induced by a novel environment, time spent in the center of an open field, novelty preference and novel object exploration. Animals exposed to cocaine during adolescence and tested as adults exhibited a greater locomotor response in a novel environment, spent less time in the center of the novel open field and spent less time with a novel object, results that are indicative of a stress or anxiogenic response to novelty or a novel situation. Adolescent animals chronically administered ethanol and tested as adults, unlike cocaine-exposed were not different from controls in a novel environment, indicated by locomotor activity or time spent with a novel object. However, ethanol-exposed animals approached the novel object more, suggesting that exposure to ethanol during development may result in less-inhibited behaviors during adulthood. The differences in adult behavioral responses after drug exposure during adolescence are likely due to differences in the mechanisms of action of the drugs and subsequent reward and/or stress responsivity. Future studies are needed to determine the neural substrates of these long lasting drug-induced changes. PMID

  2. Rat lung macrophage tumor cytotoxin production: impairment by chronic in vivo cigarette smoke exposure.

    Flick, D A; Gonzalez-Rothi, R J; Harris, J O; Gifford, G E

    1985-11-01

    Macrophages in the presence of bacteria-derived lipopolysaccharide (LPS) stimuli produce a soluble cytotoxin which is toxic to tumor cells. In this study, we examined various parameters of cytotoxin production from pulmonary lavage cells obtained from Fisher 344 cesarean-derived rats. Cultures of macrophages were derived from pulmonary lavage cells and stimulated in vitro with LPS. Cytotoxin production was assayed in vitro using an L-929 cell target assay. Pulmonary lavage preparations contained a relatively pure population of macrophages, and adherence studies revealed that nonadherent lavage cells contributed negligible amounts of cytotoxin, indicating that macrophages were responsible for cytotoxin production. After LPS stimulation, cytotoxin production became maximal within 10 h and thereafter plateaued. Doses of LPS above 0.1 microgram/ml were optimal for production, and in the absence of LPS, no cytotoxin was detected. Because cigarette smoke is the major etiological factor in the development of lung cancers and because smoking is known to profoundly alter the function of alveolar macrophages in humans and experimental animals, subsequent experiments examined the role of chronic cigarette smoke exposure on tumoricidal activity of lung macrophages. Rats were exposed in vivo for 8 wk to either cigarette smoke or air (sham-treated controls). When lavage cells were cultured and stimulated with LPS (1 microgram/ml), 5- to 10-fold less cytotoxin was produced by lavage cells from rats exposed to cigarette smoke. Similarly, using a direct cytotoxicity assay, lung macrophages of smoke-exposed animals also revealed marked impairment in cytotoxicity against L-929 cell targets, and this was noted over a wide range of macrophage:tumor target cell ratios. Another product of macrophages, interferon, was also decreased in rats exposed in vivo to cigarette smoke when compared to sham-treated controls. These results suggest that cigarette smoke exposure may impair pulmonary

  3. Effects of acute or chronic ethanol exposure during adolescence on behavioral inhibition and efficiency in a modified water maze task.

    Shawn K Acheson

    Full Text Available Ethanol is well known to adversely affect frontal executive functioning, which continues to develop throughout adolescence and into young adulthood. This is also a developmental window in which ethanol is misused by a significant number of adolescents. We examined the effects of acute and chronic ethanol exposure during adolescence on behavioral inhibition and efficiency using a modified water maze task. During acquisition, rats were trained to find a stable visible platform onto which they could escape. During the test phase, the stable platform was converted to a visible floating platform (providing no escape and a new hidden platform was added in the opposite quadrant. The hidden platform was the only means of escape during the test phase. In experiment 1, adolescent animals received ethanol (1.0 g/kg 30 min before each session during the test phase. In experiment 2, adolescent animals received chronic intermittent ethanol (5.0 g/kg for 16 days (PND30 To PND46 prior to any training in the maze. At PND72, training was initiated in the same modified water maze task. Results from experiment 1 indicated that acute ethanol promoted behavioral disinhibition and inefficiency. Experiment 2 showed that chronic intermittent ethanol during adolescence appeared to have no lasting effect on behavioral disinhibition or new spatial learning during adulthood. However, chronic ethanol did promote behavioral inefficiency. In summary, results indicate that ethanol-induced promotion of perseverative behavior may contribute to the many adverse behavioral sequelae of alcohol intoxication in adolescents and young adults. Moreover, the long-term effect of adolescent chronic ethanol exposure on behavioral efficiency is similar to that observed after chronic exposure in humans.

  4. Effects of Acute and Chronic Heavy Metal (Cu, Cd, and Zn Exposure on Sea Cucumbers (Apostichopus japonicus

    Li Li

    2016-01-01

    Full Text Available Acute and chronic toxicity tests were conducted with sea cucumber (Apostichopus japonicus exposed to heavy metals. Acute toxicity values (96 h LC50 were 2.697, 0.133, and 1.574 mg L−1 for Zn, Cu, and Cd, respectively, and were ranked in order of toxicity: Cu > Cd > Zn. Under chronic metal exposure the specific growth rates of sea cucumbers decreased with the increase of metal concentration for all the three metals. After acute metal exposure, the oxygen consumption rate (OCR decreased. The OCRs in all groups were significantly different than control (P muscle > intestine in natural sea water. After chronic Zn, Cu, and Cd exposure, the change pattern of HK and PK in respiratory tree, muscle, and intestine varied slightly. However, the activity of the enzyme showed a general trend of increase and then decrease and the higher the exposure concentration was, the earlier the highest point of enzyme activity was obtained.

  5. The chronic toxicity of bisphenol A to Caenorhabditis elegans after long-term exposure at environmentally relevant concentrations.

    Zhou, Dong; Yang, Jie; Li, Hui; Cui, Changzheng; Yu, Yunjiang; Liu, Yongdi; Lin, Kuangfei

    2016-07-01

    To investigate biological effects of bisphenol A (BPA) over the long term, the model animal Caenorhabditis elegans was used to conduct the chronic exposure. C. elegans were exposed to BPA (0.0001-10 μM) from L4 larvae to day-10 adult in the present chronic toxicity assay system. Multiple endpoints at the physiological (growth, locomotion behaviors and lifespan), biochemical (lipofuscin accumulation), molecular (stress-related genes expressions), and population (population size) levels were examined. At the physiological level, BPA exposure induced significant negative effects on the indicators. Among the endpoints, head thrash was most sensitive and the detection limit was 0.001 μM. At the biochemical level, BPA exposure induced no significant effects on lipofuscin accumulation. At the molecular level, BPA induced strong stress responses in vivo. At the population level, the population size was significantly decreased in the treatment groups from 0.1 to 10 μM. Compared to the previous short-term toxicity evaluation, long-term exposure to BPA induced a more obvious response at the same concentration, and the phenomenon might be due to cumulative toxic effects. By the Pearson correlation analyses, cep-1 was speculated to act as an important role in BPA-induced chronic toxicity on C. elegans. PMID:27085314

  6. Ways of pharmacological prophylaxis of stochastic and deterministic effects of chronical radiation exposure

    The prophylactics of late effects of exposure is the actual medico-social problem, because now there are large groups of persons who were exposed during occupational contact and living on territories contaminated by radionuclides. Most probable consequences of external and internal chronic influence of radiation may be the increase of malignant tumour frequency, the development of secondary myelo- and immuno-depressions, the earlier forming of sclerous and destructive processes, and the acceleration of senescence. The role of damages in immune system was not yet understood in pathogenesis of the late effects of radiation, but there are evidences that the decreasing of the immunologic supervision in period of forming the consequences of radiation influence enables to realize the cancerogenic effect of radiation. The purposes of this investigation are to decrease the frequency or to prevent the development of radiation consequences dangerous for health and life by using the method of modification of radiogenic damages in hemopoietic and immune systems by applying the pharmacological preparations with immunomodulating effects. The investigation tasks include: the study of modifying influence of pharmacological substances with different mechanisms of effect: myelopid (immunomodulating, and regulatory), β-carotin, Calendula officinalis (immunomodulating, and antioxidant), lipamid (detoxicating); the separate or complex applications of these substances; and the development of the optimum medico-prophylactic schemes. The advantages of these indicated preparations in comparison with the known (T-activin, thymogen, cytokines, etc.) are the absence of contraindications and the possibility to use per os. (author)

  7. Metamorphosis of two amphibian species after chronic cadmium exposure in outdoor aquatic mesocosms

    James, S.M.; Little, E.E.; Semlitsch, R.D.

    2005-01-01

    Amphibian larvae at contaminated sites may experience an alteration of metamorphic traits and survival compared to amphibians in uncontaminated conditions. Effects of chronic cadmium (Cd) exposure on the metamorphosis of American toads (Bufo americanus) and southern leopard frogs (Rana sphenocephala) were determined. The two species were reared separately from shortly after hatching through metamorphosis in outdoor mesocosms (1,325-L polyethylene cattle tanks) that simulated natural ponds and enhanced environmental realism relative to the laboratory. Both species exhibited a decrease in survival with increasing initial nominal aqueous Cd concentration. Cadmium treatment did not influence mass at metamorphosis for either species when survival was included as a covariate, but increased the age at metamorphosis for the American toads. The whole body Cd content of metamorphs increased with aqueous Cd treatment level for both species, and the American toads tended to possess more elevated residues. Cadmium quickly partitioned out of the water column and accumulated in and altered the abundance of the tadpoles' diet. Cadmium-contaminated sites may produce fewer metamorphs, and those that survive will metamorphose later and contain Cd. Interspecific differences in the response variables illustrate the importance of testing multiple species when assessing risk. ?? 2005 SETAC.

  8. Modelling the propagation of effects of chronic exposure to ionising radiation from individuals to populations

    Alonzo, F. [Laboratory of Environmental Modelling, DEI/SECRE/LME, Institute of Radioprotection and Nuclear Safety (IRSN), Cadarache, Building 159, BP3, 13115 St-Paul-lez-Durance Cedex (France); Laboratory of Radioecology and Ecotoxicology, DEI/SECRE/LRE, Institute of Radioprotection and Nuclear Safety (IRSN), Cadarache Building 186, BP3, 13115 St-Paul-lez-Durance Cedex (France)], E-mail: frederic.alonzo@irsn.fr; Hertel-Aas, T. [Department of Plant and Environmental Sciences, P.O. Box 5003, Norwegian University of Life Sciences, 1432 Aas (Norway); Gilek, M. [School of Life Sciences, Soedertoern University College, 14189 Huddinge (Sweden); Gilbin, R. [Laboratory of Radioecology and Ecotoxicology, DEI/SECRE/LRE, Institute of Radioprotection and Nuclear Safety (IRSN), Cadarache Building 186, BP3, 13115 St-Paul-lez-Durance Cedex (France); Oughton, D.H. [Department of Plant and Environmental Sciences, P.O. Box 5003, Norwegian University of Life Sciences, 1432 Aas (Norway); Garnier-Laplace, J. [Laboratory of Radioecology and Ecotoxicology, DEI/SECRE/LRE, Institute of Radioprotection and Nuclear Safety (IRSN), Cadarache Building 186, BP3, 13115 St-Paul-lez-Durance Cedex (France)

    2008-09-15

    This study evaluated the potential effect of ionising radiation on population growth using simple population models and parameter values derived from chronic exposure experiments in two invertebrate species with contrasting life-history strategies. In the earthworm Eisenia fetida, models predicted increasing delay in population growth with increasing gamma dose rate (up to 0.6 generation times at 11 mGy h{sup -1}). Population extinction was predicted at 43 mGy h{sup -1}. In the microcrustacean Daphnia magna, models predicted increasing delay in population growth with increasing alpha dose rate (up to 0.8 generation times at 15.0 mGy h{sup -1}), only after two successive generations were exposed. The study examined population effects of changes in different individual endpoints (including survival, number of offspring produced and time to first reproduction). Models showed that the two species did not respond equally to equivalent levels of change, the fast growing daphnids being more susceptible to reduction in fecundity or delay in reproduction than the slow growing earthworms. This suggested that susceptibility of a population to ionising radiation cannot be considered independent of the species' life history.

  9. HIGH-Resolution CT in Chronic Pulmonary Changes after Mustard Gas Exposure

    Bagheri, M.H.; Mostafavi, S.H. [Shiraz Univ. of Medical Siences (Iran, Islamic Republic of). Dept. of Radiology; Hosseini, S.K. [Shiraz Univ. of Medical Siences (Iran, Islamic Republic of). Dept. of Internal Medicine; Alavi, S.A. [Medical Center for Chemical Warfare Victims Foundation, Shiraz (Iran, Islamic Republic of)

    2003-05-01

    Purpose: To identify the findings of high-resolution CT (HRCT) of the lung in patients with previous sulfur mustard gas exposure, and to correlate these findings with clinical and chest X-ray (CXR) results. Material and Methods: 50 consecutive patients were studied prospectively. The clinical data were recorded. Standard p.a. CXR and HRCT of the lung and spirometry were performed. The findings of CXR, HRCT and clinical and spirometry results were scored between 0 and 3 according to the severity of the findings. Results: HRCT abnormality was detected in all 50 patients (100%), while CXR was abnormal in 40 patients (80%). The most common HRCT findings was airway abnormalities (bronchial wall thickening in 100% of cases). Other important findings were suggestive of interstitial lung disease (ILD) (80%), bronchiectasis (26%), and emphysema (24%). A statistically significant correlation was found between the severity of clinical presentation and that of the HCTR scores in patients with bronchiectasis, bronchitis and ILD (p< 0.05), but not with severity scores of HRCT in patients with emphysema. No significant correlation was found between severity scores of CXR findings. HRCT evidence of bronchial wall thickening and with a lower frequency ILD were present despite normal CXR in 20% of the patients. Conclusion: The results of this study suggest that bronchial wall thickening, ILD and emphysema are common chronic pulmonary sequelae of sulfur mustard injury. HRCT of the chest should be considered as the imaging modality of choice in chemical war injury.

  10. HIGH-Resolution CT in Chronic Pulmonary Changes after Mustard Gas Exposure

    Purpose: To identify the findings of high-resolution CT (HRCT) of the lung in patients with previous sulfur mustard gas exposure, and to correlate these findings with clinical and chest X-ray (CXR) results. Material and Methods: 50 consecutive patients were studied prospectively. The clinical data were recorded. Standard p.a. CXR and HRCT of the lung and spirometry were performed. The findings of CXR, HRCT and clinical and spirometry results were scored between 0 and 3 according to the severity of the findings. Results: HRCT abnormality was detected in all 50 patients (100%), while CXR was abnormal in 40 patients (80%). The most common HRCT findings was airway abnormalities (bronchial wall thickening in 100% of cases). Other important findings were suggestive of interstitial lung disease (ILD) (80%), bronchiectasis (26%), and emphysema (24%). A statistically significant correlation was found between the severity of clinical presentation and that of the HCTR scores in patients with bronchiectasis, bronchitis and ILD (p< 0.05), but not with severity scores of HRCT in patients with emphysema. No significant correlation was found between severity scores of CXR findings. HRCT evidence of bronchial wall thickening and with a lower frequency ILD were present despite normal CXR in 20% of the patients. Conclusion: The results of this study suggest that bronchial wall thickening, ILD and emphysema are common chronic pulmonary sequelae of sulfur mustard injury. HRCT of the chest should be considered as the imaging modality of choice in chemical war injury

  11. Acute and chronic ethanol exposure differentially regulate CB1 receptor function at glutamatergic synapses in the rat basolateral amygdala.

    Robinson, Stacey L; Alexander, Nancy J; Bluett, Rebecca J; Patel, Sachin; McCool, Brian A

    2016-09-01

    The endogenous cannabinoid (eCB) system has been suggested to play a key role in ethanol preference and intake, the acute effects of ethanol, and in the development of withdrawal symptoms following ethanol dependence. Ethanol-dependent alterations in glutamatergic signaling within the lateral/basolateral nucleus of the amygdala (BLA) are critical for the development and expression of withdrawal-induced anxiety. Notably, the eCB system significantly regulates both glutamatergic and GABAergic synaptic activity within the BLA. Chronic ethanol exposure significantly alters eCB system expression within regions critical to the expression of emotionality and anxiety-related behavior, including the BLA. Here, we investigated specific interactions between the BLA eCB system and its functional regulation of synaptic activity during acute and chronic ethanol exposure. In tissue from ethanol naïve-rats, a prolonged acute ethanol exposure caused a dose dependent inhibition of glutamatergic synaptic activity via a presynaptic mechanism that was occluded by CB1 antagonist/inverse agonists SR141716a and AM251. Importantly, this acute ethanol inhibition was attenuated following 10 day chronic intermittent ethanol vapor exposure (CIE). CIE exposure also significantly down-regulated CB1-mediated presynaptic inhibition at glutamatergic afferent terminals but spared CB1-inhibition of GABAergic synapses arising from local inhibitory-interneurons. CIE also significantly elevated BLA N-arachidonoylethanolamine (AEA or anandamide) levels and decreased CB1 receptor protein levels. Collectively, these data suggest a dynamic regulation of the BLA eCB system by acute and chronic ethanol. PMID:26707595

  12. Research progress in study of accidental hypothermia

    Rui YUAN

    2016-04-01

    Full Text Available Accidental hypothermia refers to a state of lowering of core body temperature down to 35 ℃induced by drowning, burial in snow and prolonged exposure to cold environment, etc. Hypothermia may affect the cardiovascular system, respiratory system, digestive system, etc. The triad consisting "hypothermia, acidosis and coagulopathy" is an important factor accelerating the death of patients. Early, timely application of rewarming measures is regarded as the basic principle in treatment of hypothermia. A series of rewarming measures, such as infusion of warm fluids, inspiration of warm air, abdominal infusion of warm fluid, instruction of warm fluid into pleural cavity, intravenous infusion of warm fluid, rewarming through ECMO, etc. have been used recently. Advance in research on the classification of hypothermia, its impact to the body and the treatment methods are reviewed in present paper. DOI: 10.11855/j.issn.0577-7402.2016.04.15

  13. Organizational influence on the occurrence of work accidents involving exposure to biological material La influencia de la organización en la ocurrencia de accidentes de trabajo con exposición a material biológico Influência organizacional na ocorrência de acidentes de trabalho com exposição a material biológico

    Maria Helena Palucci Marziale

    2013-02-01

    Full Text Available OBJECTIVES: to analyze work accidents involving exposure to biological materials which took place among personnel working in nursing and to evaluate the influence of the organizational culture on the occurrence of these accidents. METHOD: a retrospective, analytical study, carried out in two stages in a hospital that was part of the Network for the Prevention of Work Accidents. The first stage involved the analysis of the characteristics of the work accidents involving exposure to biological materials as recorded over a seven-year period by the nursing staff in the hospital studied, and registered in the Network databank. The second stage involved the analysis of 122 nursing staff members' perception of the institutional culture, who were allocated to the control group (workers who had not had an accident and the case group (workers who had had an accident. RESULTS: 386 accidents had been recorded: percutaneous lesions occurred in 79% of the cases, needles were the materials involved in 69.7% of the accidents, and in 81.9% of the accident there was contact with blood. Regarding the influence of the organizational culture on the occurrence of accidents, the results obtained through the analysis of the two groups did not demonstrate significant differences between the average scores attributed by the workers in each organizational value or practice category. It is concluded that accidents involving exposure to biological material need to be avoided, however, it was not possible to confirm the influence of organizational values or practices on workers' behavior concerning the occurrence of these accidents.OBJETIVOS: analizar los accidentes de trabajo con exposición a material biológico entre el personal de enfermería y evaluar la influencia de la cultura organizacional en la ocurrencia de accidentes de este tipo. MÉTODO: estudio retrospectivo, analítico, desarrollado en dos etapas en un Hospital de la Red para la Prevención de Accidentes. En

  14. Effects of an acute and a sub-chronic 900 MHz GSM exposure on brain activity and behaviors of rats

    Elsa Brillaud; Aleksandra Piotrowski; Anthony Lecomte; Franck Robidel; Rene de Seze [Toxicology Unit, INERIS, Verneuil en Halatte (France)

    2006-07-01

    Radio frequencies are suspected to produce health effects. Concerning the mobile phone technology, according to position during use (close to the head), possible effects of radio frequencies on the central nervous system have to be evaluated. Previous works showed contradictory results, possibly due to experimental design diversity. In the framework of R.A.M.P. 2001 project, we evaluated possible effect of a 900 MHz GSM exposure on the central nervous system of rat at a structural, a functional and a behavioral level after acute or sub-chronic exposures. Rats were exposed using a loop antenna system to different S.A.R. levels and durations, according to results of the French C.O.M.O.B.I.O. 2001 project. A functional effect was found (modification of the cerebral activity and increase of the glia surface) after an acute exposure, even at a low level of brain averaged S.A.R. (1.5 W/kg). No cumulative effect was observed after a sub-chronic exposure (same amplitude of the effect). No structural or behavioral consequence was noted. We do not conclude on the neurotoxicity of the 900 MHz GSM exposure on the rat brain. Our results do not indicate any health risk. (authors)

  15. Effects of an acute and a sub-chronic 900 MHz GSM exposure on brain activity and behaviors of rats

    Radio frequencies are suspected to produce health effects. Concerning the mobile phone technology, according to position during use (close to the head), possible effects of radio frequencies on the central nervous system have to be evaluated. Previous works showed contradictory results, possibly due to experimental design diversity. In the framework of R.A.M.P. 2001 project, we evaluated possible effect of a 900 MHz GSM exposure on the central nervous system of rat at a structural, a functional and a behavioral level after acute or sub-chronic exposures. Rats were exposed using a loop antenna system to different S.A.R. levels and durations, according to results of the French C.O.M.O.B.I.O. 2001 project. A functional effect was found (modification of the cerebral activity and increase of the glia surface) after an acute exposure, even at a low level of brain averaged S.A.R. (1.5 W/kg). No cumulative effect was observed after a sub-chronic exposure (same amplitude of the effect). No structural or behavioral consequence was noted. We do not conclude on the neurotoxicity of the 900 MHz GSM exposure on the rat brain. Our results do not indicate any health risk. (authors)

  16. Chronic hydrocarbon exposure of harlequin ducks in areas affected by the Selendang Ayu oil spill at Unalaska Island, Alaska

    Flint, Paul L.; Schamber, J.L.; Trust, K.A.; Miles, A.K.; Henderson, J.D.; Wilson, B.W.

    2012-01-01

    We evaluated chronic exposure of harlequin ducks (Histrionicus histrionicus) to hydrocarbons associated with the 2004 M/V Selendang Ayu oil spill at Unalaska Island, Alaska. We measured levels of hepatic 7-ethoxyresorufin-O-deethylase activity (EROD) in liver biopsy samples as an indicator of hydrocarbon exposure in three oiled bays and one reference bay in 2005, 2006, and 2008. Median EROD activity in ducks from oiled bays was significantly higher than in the reference bay in seven of nine pairwise comparisons. These results indicated that harlequin ducks were exposed to lingering hydrocarbons more than three years after the spill.

  17. Plants experiencing chronic internal exposure to ionizing radiation exhibit higher frequency of homologous recombination than acutely irradiated plants

    Kovalchuk, O.; Kovalchuk, I.; Hohn, B. [Friedrich Miescher Institute, P.O. Box 2543, CH-4002 Basel (Switzerland); Arkhipov, A. [Chernobyl Scientific and Technical Center of International Research, Shkolnaya Str. 6, 255620 Chernobyl (Ukraine); Barylyak, I.; Karachov, I. [Ukrainian Scientific Genetics Center, Popudrenko Str. 50, 253660 Kiev (Ukraine); Titov, V. [Ivano-Frankivsk State Medical Academy, Galitska Str.2, 284000 Ivano-Frankivsk (Ukraine)

    2000-04-03

    Ionizing radiation (IR) is a known mutagen responsible for causing DNA strand breaks in all living organisms. Strand breaks thus created can be repaired by different mechanisms, including homologous recombination (HR), one of the key mechanisms maintaining genome stability [A. Britt, DNA damage and repair in plants, Annu. Rev. Plant. Phys. Plant Mol. Biol., 45 (1996) 75-100; H. Puchta, B. Hohn, From centiMorgans to basepairs: homologous recombination in plants, Trends Plant Sci., 1 (1996) 340-348.]. Acute or chronic exposure to IR may have different influences on the genome integrity. Although in a radioactively contaminated environment plants are mostly exposed to chronic pollution, evaluation of both kinds of influences is important. Estimation of the frequency of HR in the exposed plants may serve as an indication of genome stability. We used previously generated Arabidopsis thaliana and Nicotiana tabacum plants, transgenic for non-active versions of the {beta}-glucoronidase gene (uidA) [P. Swoboda, S. Gal, B. Hohn, H. Puchta, Intrachromosomal homologous recombination in whole plants, EMBO J., 13 (1994) 484-489; H. Puchta, P. Swoboda, B. Hohn, Induction of homologous DNA recombination in whole plants, Plant, 7 (1995) 203-210.] serving as a recombination substrate, to study the influence of acute and chronic exposure to IR on the level of HR as example of genome stability in plants. Exposure of seeds and seedlings to 0.1 to 10.0 Gy 60Co resulted in increased HR frequency, although the effect was more pronounced in seedlings. For the study of the influence of chronic exposure to IR, plants were grown on two chemically different types of soils, each artificially contaminated with equal amounts of 137Cs. We observed a strong and significant correlation between the frequency of HR in plants, the radioactivity of the soil samples and the doses of radiation absorbed by plants (in all cases r0.9, n=6, P<0.05). In addition, we noted that plants grown in soils with

  18. Plants experiencing chronic internal exposure to ionizing radiation exhibit higher frequency of homologous recombination than acutely irradiated plants

    Ionizing radiation (IR) is a known mutagen responsible for causing DNA strand breaks in all living organisms. Strand breaks thus created can be repaired by different mechanisms, including homologous recombination (HR), one of the key mechanisms maintaining genome stability [A. Britt, DNA damage and repair in plants, Annu. Rev. Plant. Phys. Plant Mol. Biol., 45 (1996) 75-100; H. Puchta, B. Hohn, From centiMorgans to basepairs: homologous recombination in plants, Trends Plant Sci., 1 (1996) 340-348.]. Acute or chronic exposure to IR may have different influences on the genome integrity. Although in a radioactively contaminated environment plants are mostly exposed to chronic pollution, evaluation of both kinds of influences is important. Estimation of the frequency of HR in the exposed plants may serve as an indication of genome stability. We used previously generated Arabidopsis thaliana and Nicotiana tabacum plants, transgenic for non-active versions of the β-glucoronidase gene (uidA) [P. Swoboda, S. Gal, B. Hohn, H. Puchta, Intrachromosomal homologous recombination in whole plants, EMBO J., 13 (1994) 484-489; H. Puchta, P. Swoboda, B. Hohn, Induction of homologous DNA recombination in whole plants, Plant, 7 (1995) 203-210.] serving as a recombination substrate, to study the influence of acute and chronic exposure to IR on the level of HR as example of genome stability in plants. Exposure of seeds and seedlings to 0.1 to 10.0 Gy 60Co resulted in increased HR frequency, although the effect was more pronounced in seedlings. For the study of the influence of chronic exposure to IR, plants were grown on two chemically different types of soils, each artificially contaminated with equal amounts of 137Cs. We observed a strong and significant correlation between the frequency of HR in plants, the radioactivity of the soil samples and the doses of radiation absorbed by plants (in all cases r0.9, n=6, P<0.05). In addition, we noted that plants grown in soils with different

  19. PROVANN: Model System for Chronic Exposure of Larval and Adult Fish to Releases from Offshore Petroleum Platforms

    Produced water from offshore oil and gas production platforms contains a variety of hydrocarbons, heavy metals, and production chemicals. Vertical and horizontal mixing generally brings concentrations in discharge plumes below level associated with acute effects within 500 or 1000 m of the source. Chronic effects outside this region remain a potential problem. The purpose of PROVANN, the system of models described in this paper, is to assess the potential for chronic effects from produced water. The preliminary focus is on potential bioaccumulation and boimagnification of produced water constituents in the marine food web. Other possible types of chronic effects, such as reduced fecundity, or pheromone response interference, can also be assessed to the extent that such effects may be correlated with exposure. PROVANN simulates 3-dimensional transport, dilution, and degradation of chemicals released into the water, from one or more simultaneous sources. 8 refs., 10 figs., 3 tabs

  20. Chronic Exposure to Zinc Chromate Induces Centrosome Amplification and Spindle Assembly Checkpoint Bypass in Human Lung Fibroblasts

    Holmes, Amie L.; Wise, Sandra S.; Pelsue, Stephen C.; Aboueissa, AbouEl-Makarim; Lingle, Wilma; Salisbury, Jeffery; Gallagher, Jamie; Wise, John Pierce

    2010-01-01

    Hexavalent chromium (Cr(VI)) compounds are known human lung carcinogens. Solubility plays an important role in its carcinogenicity with the particulate or insoluble form being the most potent. Of the particulate Cr(VI) compounds, zinc chromate appears to be the most potent carcinogen, however, very few studies have investigated its carcinogenic mechanism. In this study, we investigated the ability of chronic exposure to zinc chromate to induce numerical chromosome instability. We found no inc...

  1. Chronic exposure to low doses of pharmaceuticals disturbs the hepatic expression of circadian genes in lean and obese mice.

    Anthérieu, Sébastien; Le Guillou, Dounia; Coulouarn, Cédric; Begriche, Karima; Trak-Smayra, Viviane; Martinais, Sophie; Porceddu, Mathieu; Robin, Marie-Anne; Fromenty, Bernard

    2014-01-01

    International audience Drinking water can be contaminated with pharmaceuticals. However, it is uncertain whether this contamination can be harmful for the liver, especially during obesity. Hence, the goal of our study was to determine whether chronic exposure to low doses of pharmaceuticals could have deleterious effects on livers of lean and obese mice. To this end, lean and ob/ob male mice were treated for 4 months with a mixture of 11 drugs provided in drinking water at concentrations r...

  2. Use of Polar Organic Chemical Integrative Samplers to assess the effects of chronic pesticide exposure on biofilms

    Morin, S.; Pesce, S.; Kim Tiam, S.; Libert, X.; Coquery, M.; Mazzella, N.

    2012-01-01

    The responses of aquatic organisms to chronic exposure to environmental concentrations of toxicants, often found in mixtures, are poorly documented. Here passive sampler extracts were used in experimental contamination of laboratory channels, to investigate their effects on natural biofilm communities. A realistic mixture of pesticides extracted from POCIS (Polar Organic Chemical Integrative Samplers) was used to expose biofilms in laboratory channels to total pesticide concentrations averagi...

  3. CD44v6 expression in human skin keratinocytes as a possible mechanism for carcinogenesis associated with chronic arsenic exposure

    Huang, S.; Guo, S.; Guo, F; Yang, Q.; XIAO, X.; Murata, M.; Ohnishi, S.; Kawanishi, S; Ma, N

    2013-01-01

    Inorganic arsenic is a well-known human skin carcinogen. Chronic arsenic exposure results in various types of human skin lesions, including squamous cell carcinoma (SCC). To investigate whether mutant stem cells participate in arsenic-associated carcinogenesis, we repeatedly exposed the human spontaneously immortalized skin keratinocytes (HaCaT) cell line to an environmentally relevant level of arsenic (0.05 ppm) in vitrofor 18 weeks. Following sodium arsenite administration, cell cycle, colo...

  4. Neutralisation of interleukin-13 in mice prevents airway pathology caused by chronic exposure to house dust mite.

    Kate L Tomlinson

    Full Text Available BACKGROUND: Repeated exposure to inhaled allergen can cause airway inflammation, remodeling and dysfunction that manifests as the symptoms of allergic asthma. We have investigated the role of the cytokine interleukin-13 (IL-13 in the generation and persistence of airway cellular inflammation, bronchial remodeling and deterioration in airway function in a model of allergic asthma caused by chronic exposure to the aeroallergen House Dust Mite (HDM. METHODOLOGY/PRINCIPAL FINDINGS: Mice were exposed to HDM via the intranasal route for 4 consecutive days per week for up to 8 consecutive weeks. Mice were treated either prophylactically or therapeutically with a potent neutralising anti-IL-13 monoclonal antibody (mAb administered subcutaneously (s.c.. Airway cellular inflammation was assessed by flow cytometry, peribronchial collagen deposition by histocytochemistry and airway hyperreactivity (AHR by invasive measurement of lung resistance (R(L and dynamic compliance (C(dyn. Both prophylactic and therapeutic treatment with an anti-IL-13 mAb significantly inhibited (P<0.05 the generation and maintenance of chronic HDM-induced airway cellular inflammation, peribronchial collagen deposition, epithelial goblet cell upregulation. AHR to inhaled methacholine was reversed by prophylactic but not therapeutic treatment with anti-IL-13 mAb. Both prophylactic and therapeutic treatment with anti-IL-13 mAb significantly reversed (P<0.05 the increase in baseline R(L and the decrease in baseline C(dyn caused by chronic exposure to inhaled HDM. CONCLUSIONS/SIGNIFICANCE: These data demonstrate that in a model of allergic lung disease driven by chronic exposure to a clinically relevant aeroallergen, IL-13 plays a significant role in the generation and persistence of airway inflammation, remodeling and dysfunction.

  5. Chronic inorganic arsenic exposure in vitro induces a cancer cell phenotype in human peripheral lung epithelial cells

    Person, Rachel J.; Olive Ngalame, Ntube N.; Makia, Ngome L.; Bell, Matthew W.; Waalkes, Michael P.; Tokar, Erik J., E-mail: tokare@niehs.nih.gov

    2015-07-01

    Inorganic arsenic is a human lung carcinogen. We studied the ability of chronic inorganic arsenic (2 μM; as sodium arsenite) exposure to induce a cancer phenotype in the immortalized, non-tumorigenic human lung peripheral epithelial cell line, HPL-1D. After 38 weeks of continuous arsenic exposure, secreted matrix metalloproteinase-2 (MMP2) activity increased to over 200% of control, levels linked to arsenic-induced cancer phenotypes in other cell lines. The invasive capacity of these chronic arsenic-treated lung epithelial (CATLE) cells increased to 320% of control and colony formation increased to 280% of control. CATLE cells showed enhanced proliferation in serum-free media indicative of autonomous growth. Compared to control cells, CATLE cells showed reduced protein expression of the tumor suppressor gene PTEN (decreased to 26% of control) and the putative tumor suppressor gene SLC38A3 (14% of control). Morphological evidence of epithelial-to-mesenchymal transition (EMT) occurred in CATLE cells together with appropriate changes in expression of the EMT markers vimentin (VIM; increased to 300% of control) and e-cadherin (CDH1; decreased to 16% of control). EMT is common in carcinogenic transformation of epithelial cells. CATLE cells showed increased KRAS (291%), ERK1/2 (274%), phosphorylated ERK (p-ERK; 152%), and phosphorylated AKT1 (p-AKT1; 170%) protein expression. Increased transcript expression of metallothioneins, MT1A and MT2A and the stress response genes HMOX1 (690%) and HIF1A (247%) occurred in CATLE cells possibly in adaptation to chronic arsenic exposure. Thus, arsenic induced multiple cancer cell characteristics in human peripheral lung epithelial cells. This model may be useful to assess mechanisms of arsenic-induced lung cancer. - Highlights: • Chronic arsenic exposure transforms a human peripheral lung epithelia cell line. • Cells acquire characteristics in common with human lung adenocarcinoma cells. • These transformed cells provide a

  6. Effects of Chronic and Acute Ozone Exposure on Lipid Peroxidation and Antioxidant Capacity in Healthy Young Adults

    Chen, Connie; Arjomandi, Mehrdad; Balmes, John; Tager, Ira; Holland, Nina

    2007-01-01

    Background There is growing evidence for the role of oxidative damage in chronic diseases. Although ozone (O3) is an oxidant pollutant to which many people are exposed, few studies have examined whether O3 induces oxidative stress in humans. Objectives This study was designed to assess the effect of short-and long-term O3 exposures on biomarkers of oxidative stress in healthy individuals. Methods Biomarkers of lipid peroxidation, 8-isoprostane (8-iso-PGF), and antioxidant capacity ferric redu...

  7. Chronic inorganic arsenic exposure in vitro induces a cancer cell phenotype in human peripheral lung epithelial cells

    Inorganic arsenic is a human lung carcinogen. We studied the ability of chronic inorganic arsenic (2 μM; as sodium arsenite) exposure to induce a cancer phenotype in the immortalized, non-tumorigenic human lung peripheral epithelial cell line, HPL-1D. After 38 weeks of continuous arsenic exposure, secreted matrix metalloproteinase-2 (MMP2) activity increased to over 200% of control, levels linked to arsenic-induced cancer phenotypes in other cell lines. The invasive capacity of these chronic arsenic-treated lung epithelial (CATLE) cells increased to 320% of control and colony formation increased to 280% of control. CATLE cells showed enhanced proliferation in serum-free media indicative of autonomous growth. Compared to control cells, CATLE cells showed reduced protein expression of the tumor suppressor gene PTEN (decreased to 26% of control) and the putative tumor suppressor gene SLC38A3 (14% of control). Morphological evidence of epithelial-to-mesenchymal transition (EMT) occurred in CATLE cells together with appropriate changes in expression of the EMT markers vimentin (VIM; increased to 300% of control) and e-cadherin (CDH1; decreased to 16% of control). EMT is common in carcinogenic transformation of epithelial cells. CATLE cells showed increased KRAS (291%), ERK1/2 (274%), phosphorylated ERK (p-ERK; 152%), and phosphorylated AKT1 (p-AKT1; 170%) protein expression. Increased transcript expression of metallothioneins, MT1A and MT2A and the stress response genes HMOX1 (690%) and HIF1A (247%) occurred in CATLE cells possibly in adaptation to chronic arsenic exposure. Thus, arsenic induced multiple cancer cell characteristics in human peripheral lung epithelial cells. This model may be useful to assess mechanisms of arsenic-induced lung cancer. - Highlights: • Chronic arsenic exposure transforms a human peripheral lung epithelia cell line. • Cells acquire characteristics in common with human lung adenocarcinoma cells. • These transformed cells provide a

  8. Chronic CO2 exposure markedly increases the incidence of cataracts in juvenile Atlantic cod Gadus morhua L

    Moran, Damian; Tubbs, Lincoln; Støttrup, Josianne G.

    2012-01-01

    A study was undertaken to test the affect of chronic exposure to elevated dissolved carbon dioxide on juvenile Atlantic cod. The CO2 treatment concentrations were designated as low (1–2mgL−1, 1000μatm), medium (8mgL−1, 3500μatm) and high (18mgL−1, 8500μatm), and the fish were reared at 10°C and 2...

  9. Adesão a protocolo pós-exposição ocupacional de acidentes entre cirurgiões dentistas Adhesión a protocolo post exposición ocupacional de accidentes entre cirujanos dentistas Compliance with occupational post-exposure protocol for injuries among dental surgeons

    Andréa Maria Eleutério de Barros Lima Martins

    2010-06-01

    Full Text Available OBJETIVO: Analisar a adesão a protocolo pós-exposição ocupacional a acidentes e os fatores relacionados à adesão entre cirurgiões-dentistas. MÉTODOS: Estudo transversal realizado em Montes Claros, MG, de 2007 a 2008, com cirurgiões-dentistas em atividade clínica com relato de ocorrência de acidentes com instrumentos perfurocortantes no seu exercício profissional. As variáveis referentes à caracterização do dentista, condições de trabalho dos dentistas, caracterização da clientela atendida, características dos acidentes com instrumentos perfurocortantes sofridos pelos dentistas e condutas pós-acidentes foram avaliadas por meio de um questionário estruturado, previamente testado. Os dados foram submetidos à análise descritiva e ao teste qui-quadrado (p OBJETIVO: Analizar la adhesión a protocolo post exposición ocupacional a accidentes y los factores relacionados a la adhesión entre cirujanos dentistas. MÉTODOS: Estudio transversal realizado en Montes Claros, Sureste de Brasil, de 2007 a 2008, con cirujanos dentistas en actividad clínica con relato de ocurrencia de accidentes con instrumentos perfurocortantes en el ejercicio profesional. Las variables relacionadas con la caracterización del dentista, condiciones de trabajo de los dentistas, caracterización de la clientela atendida, características de los accidentes con instrumentos perfurocortantes sufridos por los dentistas y conductas post accidentes fueron evaluadas por medio de un cuestionario estructurado, previamente testado. Los datos fueron sometidos al análisis descriptivo y a la prueba de chi-cuadrado (pOBJECTIVE: To analyze the compliance with occupational post-exposure protocol for accidents and factors associated with compliance among dental surgeons. METHODS: A cross-sectional study was performed in the municipality of Montes Claros, Southeastern Brazil, from 2007 to 2008, with accident reports from needles and sharp instruments among practicing

  10. Association between Blood Dioxin Level and Chronic Kidney Disease in an Endemic Area of Exposure.

    Chien-Yuan Huang

    Full Text Available Dioxin is an industrial pollutant related to various diseases, but epidemiological data on its effects on the kidney are limited. Therefore, we conducted a study to evaluate the association between dioxin exposure and chronic kidney disease (CKD and identify the related factors.We conducted a community-based cross-sectional study and recruited participants from an area where the residents were exposed to dioxin released from a factory. We defined a "high dioxin level" as polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs ≥ 20 pg WHO98-TEQDF/g lipid in the serum and defined CKD as having an estimated glomerular filtration rate (e-GFR ≤ 60 mL/min/1.73m2 or a diagnosis of CKD by a physician. The renal function was assessed between 2005 and 2010, and we excluded those who had had kidney diseases before the study started. Comparisons between patients of CKD and those who did not have CKD were made to identify the risk factors for CKD.Of the 2898 participants, 1427 had high dioxin levels, and 156 had CKD. In the univariate analyses, CKD was associated with high dioxin levels, age, gender, metabolic syndrome, diabetes mellitus, hypertension, and high insulin and uric acid levels. After adjusting for other factors, we found high dioxin levels (adjusted odds ratio [AOR] = 1.76, 95% confidence interval [CI]: 1.04-2.99, female gender (AOR = 1.74, 95%CI: 1.20-2.53, hypertension (AOR = 1.68, 95%CI: 1.17-2.42, high insulin levels (AOR = 2.14, 95% CI: 1.26-3.61, high uric acid levels (AOR = 4.25, 95% CI: 2.92-6.20, and older age (AOR = 4.66, 95% CI: 1.87-11.62 for 40-64 year and AOR = 26.66, 95% CI: 10.51-67.62 for age ≥ 65 year were independent predictors of CKD.A high dioxin level was associated with an increased prevalence of CKD. Therefore, the kidney function of populations with exposure to dioxin should be monitored.

  11. Yohimbine reinstates extinguished 3,4-methylenedioxymethamphetamine (MDMA; ecstasy) seeking in rats with prior exposure to chronic yohimbine.

    Ball, Kevin T; Jarsocrak, Hanna; Hyacinthe, Johanna; Lambert, Justina; Lockowitz, James; Schrock, Jordan

    2015-11-01

    Although exposure to acute stress has been shown to reinstate extinguished responding for a wide variety of drugs, no studies have investigated stress-induced reinstatement in animals with a history of 3,4-methylenedioxymethamphetamine (MDMA; ecstasy) self-administration. Thus, rats were trained to press a lever for MDMA (0.50 mg/kg/infusion) in daily sessions, and lever pressing was subsequently extinguished in the absence of MDMA and conditioned cues (light and tone). We then tested the ability of acute yohimbine (2.0 mg/kg), a pharmacological stressor, to reinstate lever-pressing under extinction conditions. Additionally, to model chronic stress, some rats were injected daily with yohimbine (5.0 mg/kg × 10 days) prior to reinstatement tests. To assess dopaminergic involvement, chronic yohimbine injections were combined with injections of SCH-23390 (0.0 or 10.0 μg/kg), a dopamine D1-like receptor antagonist. In a separate experiment, rats with a history of food self-administration were treated and tested in the same way. Results showed that acute yohimbine injections reinstated extinguished MDMA and food seeking, but only in rats with a history of chronic yohimbine exposure. Co-administration of SCH-23390 with chronic yohimbine injections prevented the potentiation of subsequent food seeking, but not MDMA seeking. These results suggest that abstinent MDMA users who also are exposed to chronic stress may be at increased risk for future relapse, and also that the effects of chronic stress on relapse may be mediated by different mechanisms depending on one's drug use history. PMID:26241170

  12. Chronic myelogenous leukemia (CML)

    CML; Chronic myeloid leukemia; Chronic granulocytic leukemia; Leukemia - chronic granulocytic ... nuclear disaster. It takes many years to develop leukemia from radiation exposure. Most people treated for cancer ...

  13. Chronic obstructive pulmonary disease

    ... airways disease; Chronic obstructive lung disease; Chronic bronchitis; Emphysema; Bronchitis - chronic ... a protein called alpha-1 antitrypsin can develop emphysema. Other risk factors for COPD are: Exposure to ...

  14. Considerations when using longitudinal cohort studies to assess dietary exposure to inorganic arsenic and chronic health outcomes.

    Scrafford, Carolyn G; Barraj, Leila M; Tsuji, Joyce S

    2016-07-01

    Dietary arsenic exposure and chronic health outcomes are of interest, due in part to increased awareness and data available on inorganic arsenic levels in some foods. Recent concerns regarding levels of inorganic arsenic, the primary form of arsenic of human health concern, in foods are based on extrapolation from adverse health effects observed at high levels of inorganic arsenic exposure; the potential for the occurrence of these health effects from lower levels of dietary inorganic arsenic exposure has not been established. In this review, longitudinal cohort studies are evaluated for their utility in estimating dietary inorganic arsenic exposure and quantifying statistically reliable associations with health outcomes. The primary limiting factor in longitudinal studies is incomplete data on inorganic arsenic levels in foods combined with the aggregation of consumption of foods with varying arsenic levels into a single category, resulting in exposure misclassification. Longitudinal cohort studies could provide some evidence to evaluate associations of dietary patterns related to inorganic arsenic exposure with risk of arsenic-related diseases. However, currently available data from longitudinal cohort studies limit causal analyses regarding the association between inorganic arsenic exposure and health outcomes. Any conclusions should therefore be viewed with knowledge of the analytical and methodological limitations. PMID:27155067

  15. The potential immune modulatory effect of chronic bisphenol A exposure on gene regulation in male medaka (Oryzias latipes) liver.

    Qiu, Wenhui; Shen, Yang; Pan, Chenyuan; Liu, Shuai; Wu, Minghong; Yang, Ming; Wang, Ke-Jian

    2016-08-01

    Bisphenol A (BPA) is a well-known estrogenic endocrine disrupting chemical (EDC) ubiquitously present in various environmental media. The present study aims to identify the responsive genes in male fish chronically exposed to low concentrations of BPA at the transcription level. We screened genes from a suppression subtractive hybridization library constructed from male medaka (Oryzias latipes) livers after 60-d exposure to 10μg/L BPA under the condition at which changes of hepatic antioxidant parameters have been previously reported. The identified genes were predicted to be involved in multiple biological processes including antioxidant physiology, endocrine system, detoxification, notably associated with the immune response processes. With real time PCR analysis, the immune-associated genes including hepcidin-like precursor, complement component and factors, MHC class I, alpha-2-macroglobulin and novel immune-type receptor 6 isoform were significantly up-regulated in a nonmonotonic dose response pattern in livers upon exposure to different concentrations of BPA (0.1, 1, 10, 100, 1000μg/L). Our results demonstrated a negative impact on gene regulation in fish chronically exposed to relatively low and environmentally relevant concentrations of BPA, and suggested the potential immune modulatory effect of chronic EDC exposure on fish. The immunotoxicity of BPA and other EDCs should be much concerned for the health of human beings and other vertebrates exposed to it. PMID:27104808

  16. Chronic intermittent ethanol exposure and withdrawal leads to adaptations in nucleus accumbens core postsynaptic density proteome and dendritic spines.

    Uys, Joachim D; McGuier, Natalie S; Gass, Justin T; Griffin, William C; Ball, Lauren E; Mulholland, Patrick J

    2016-05-01

    Alcohol use disorder is a chronic relapsing brain disease characterized by the loss of ability to control alcohol (ethanol) intake despite knowledge of detrimental health or personal consequences. Clinical and pre-clinical models provide strong evidence for chronic ethanol-associated alterations in glutamatergic signaling and impaired synaptic plasticity in the nucleus accumbens (NAc). However, the neural mechanisms that contribute to aberrant glutamatergic signaling in ethanol-dependent individuals in this critical brain structure remain unknown. Using an unbiased proteomic approach, we investigated the effects of chronic intermittent ethanol (CIE) exposure on neuroadaptations in postsynaptic density (PSD)-enriched proteins in the NAc of ethanol-dependent mice. Compared with controls, CIE exposure significantly changed expression levels of 50 proteins in the PSD-enriched fraction. Systems biology and functional annotation analyses demonstrated that the dysregulated proteins are expressed at tetrapartite synapses and critically regulate cellular morphology. To confirm this latter finding, the density and morphology of dendritic spines were examined in the NAc core of ethanol-dependent mice. We found that CIE exposure and withdrawal differentially altered dendrite diameter and dendritic spine density and morphology. Through the use of quantitative proteomics and functional annotation, these series of experiments demonstrate that ethanol dependence produces neuroadaptations in proteins that modify dendritic spine morphology. In addition, these studies identified novel PSD-related proteins that contribute to the neurobiological mechanisms of ethanol dependence that drive maladaptive structural plasticity of NAc neurons. PMID:25787124

  17. Uncertainty and sensitivity analysis of chronic exposure results with the MACCS reactor accident consequence model

    Uncertainty and sensitivity analysis techniques based on Latin hypercube sampling, partial correlation analysis and stepwise regression analysis are used in an investigation with the MACCS model of the chronic exposure pathways associated with a severe accident at a nuclear power station. The primary purpose of this study is to provide guidance on the variables to be considered in future review work to reduce the uncertainty in the important variables used in the calculation of reactor accident consequences. The effects of 75 imprecisely known input variables on the following reactor accident consequences are studied: crop growing season dose, crop long-term dose, water ingestion dose, milk growing season dose, long-term groundshine dose, long-term inhalation dose, total food pathways dose, total ingestion pathways dose, total long-term pathways dose, total latent cancer fatalities, area-dependent cost, crop disposal cost, milk disposal cost, population-dependent cost, total economic cost, condemnation area, condemnation population, crop disposal area and milk disposal area. When the predicted variables are considered collectively, the following input variables were found to be the dominant contributors to uncertainty: dry deposition velocity, transfer of cesium from animal feed to milk, transfer of cesium from animal feed to meat, ground concentration of Cs-134 at which the disposal of milk products will be initiated, transfer of Sr-90 from soil to legumes, maximum allowable ground concentration of Sr-90 for production of crops, fraction of cesium entering surface water that is consumed in drinking water, groundshine shielding factor, scale factor defining resuspension, dose reduction associated with decontamination, and ground concentration of 1-131 at which disposal of crops will be initiated due to accidents that occur during the growing season

  18. Effect of chronic pesticide exposure in farm workers of a Mexico community.

    Payán-Rentería, Rolando; Garibay-Chávez, Guadalupe; Rangel-Ascencio, Raul; Preciado-Martínez, Veronica; Muñoz-Islas, Laura; Beltrán-Miranda, Claudia; Mena-Munguía, Salvador; Jave-Suárez, Luis; Feria-Velasco, Alfredo; De Celis, Ruth

    2012-01-01

    Pesticides are frequently used substances worldwide, even when the use of some of them is forbidden due to the recognized adverse effect they have on the health of not only the people who apply the pesticides, but also of those that consume the contaminated products. The objectives of this study were to know the health issues of farm workers chronically exposed to pesticides, to evaluate possible damage at genetic level, as well as to explore some hepatic, renal, and hematological alterations. A transversal comparative study was performed between 2 groups, one composed of 25 farm workers engaged in pesticide spraying, and a control group of 21 workers not exposed to pesticides; both groups belonged to the Nextipac community in Jalisco, Mexico. Each member of both groups underwent a full medical history. Blood samples were taken from all farm workers in order to obtain a complete blood count and chemistry, clinical chemistry, lipid profile, liver and kidney function tests, erythrocyte cholinesterase quantification, lipid peroxidation profile, and free DNA fragment quantification. For the information analysis, central tendency and dispersion measurements were registered. In order to know the differences between groups, a cluster multivariate method was used, as well as prevalence reasons. The most used pesticides were mainly organophosphates, triazines and organochlorine compounds. The exposed group showed acute poisoning (20% of the cases) and diverse alterations of the digestive, neurological, respiratory, circulatory, dermatological, renal, and reproductive system probably associated to pesticide exposure. More importantly, they presented free DNA fragments in plasma (90.8 vs 49.05 ng/mL) as well as a higher level of lipid peroxidation (41.85 vs. 31.91 nmol/mL) in comparison with those data from unexposed farm workers. These results suggest that there exist health hazards for those farm workers exposed to pesticides, at organic and cellular levels. PMID:22315932

  19. Reproductive toxicity in rats after chronic oral exposure to low dose of depleted uranium

    Objective: To study the reproductive toxicity in rats induced by low dose of depleted uranium (DU). Methods: Male and female rats(F0 generation) were exposed to DU in food at doses of 0, 0.4, 4 and 40 mg·kg-1·d-1 for 160 days, respectively. Then the activities of enzymes in testis and sexual hormone contents in serum were detected. Mature male rats were mated with female rats exposed to the same doses for 14 days. Pregnant rate and normal labor rate in F0 rats were detected, as well as the survival rate and weight of F1 rats within 21 d after birth. Results: No adverse effects of DU on fertility were evident at any dose in F0 rats. Compared with control group, the rate of pregnancy, normal labor, survival of offspring birth and offspring nurture in F1 generation of high-dose group reduced to 40.0%, 33.3%, 33.3%, and 33.3%, respectively. The sexual hormone contents in F0 generation exposed increased, but those in Fl rats decreased significantly. The activities of lactate dehydrogenase-X (LDH-X) decreased in F1 rats exposed to high-dose of DU, and those of sorbitol dehydrogenase (SDH), LDH and Na+-K+-ATPase decreased in F1 rats exposed to DU. Conclusions: Reproduction function, growth and development of F0 rats are not obviously affected after chronic oral exposure to DU, while the toxicity effects in F1 generation was observed at any dose. (authors)

  20. Uncertainty and sensitivity analysis of chronic exposure results with the MACCS reactor accident consequence model

    Uncertainty and sensitivity analysis techniques based on Latin hypercube sampling, partial correlation analysis and stepwise regression analysis are used in an investigation with the MACCS model of the chronic exposure pathways associated with a severe accident at a nuclear power station. The primary purpose of this study is to provide guidance on the variables to be considered in future review work to reduce the uncertainty in the important variables used in the calculation of reactor accident consequences. The effects of 75 imprecisely known input variables on the following reactor accident consequences are studied: crop growing-season dose, crop long-term dose, water ingestion dose, milk growing-season dose, long-term groundshine dose, long-term inhalation dose, total food pathways dose, total ingestion pathways dose, total long-term pathways dose, total latent cancer fatalities, area-dependent cost, crop disposal cost, milk disposal cost, population-dependent cost, total economic cost, condemnation area, condemnation population, crop disposal area and milk disposal area. When the predicted variables are considered collectively, the following input variables were found to be the dominant contributors to uncertainty: dry deposition velocity, transfer of cesium from animal feed to milk, transfer of cesium from animal feed to meet, ground concentration of Cs-134 at which the disposal of milk products will be initiated, transfer of Sr-90 from soil to legumes, maximum allowable ground concentration of Sr-90 for production of crops, fraction of cesium entering surface water that is consumed in drinking water, groundshine shielding factor, scale factor defining resuspension, dose reduction associated with decontamination, and ground concentration of I-131 at which disposal of crops will be initiated due to accidents that occur during the growing season. Reducing the uncertainty in the preceding variables was found to substantially reduce the uncertainty in the

  1. Micronucleus assay in human lymphocytes as a bio dosimeter of in vivo acute and chronic exposures

    To assess the persistence over time of micronuclei (MN) in lymphocytes of cancer patients after radiotherapy and, consequently, to verify the suitability of MN test as a dosimeter for monitoring in vivo ionizing radiation damage, the cytokinesis-blocked MN assay was applied in peripheral blood lymphocytes of cervix and head and neck cancer patients (n = 34). The evaluation of data suggests that: 1) MN frequency increases linearly with the equivalent total-body absorbed dose (R2 = 0,9; P=0,015); 2) The distribution of the MN yields deviates significantly from Poisson with the increase of equivalent total-body dose (σ2/y = 1,14 mean value); 3) The comparison of spontaneous MN frequencies in healthy subjects with those in cancer patients, prior to radiotherapy, shows significant differences (p<0,01); and 4) It is observed a general decline in MN frequencies with time after radiotherapy, with considerable variations between patients. The kinetics of elimination of MN seems to follow a two-term exponential function, with a short and a long term. Patients with the highest equivalent total-body dose (total tumoral dose: 60-80 Gy) initially tend to have the fastest decline. At 6-18 months of follow-up time 11 of the 17 patients, evaluated 2-480 months post-treatment, showed higher frequencies of MN than their respective levels before radiation therapy, indicating persistence of radiation induced cytogenetic damage. Further studies modeling changes in chromosome aberrations with acute and chronic exposures should provide perspectives on biological dosimetry in accident situations in which there is a blood sampling delay and on biological monitoring of human populations exposed to ionizing radiation. (author)

  2. Uncertainty and sensitivity analysis of chronic exposure results with the MACCS reactor accident consequence model

    Helton, J.C. [Arizona State Univ., Tempe, AZ (United States); Johnson, J.D.; Rollstin, J.A. [Gram, Inc., Albuquerque, NM (United States); Shiver, A.W.; Sprung, J.L. [Sandia National Labs., Albuquerque, NM (United States)

    1995-01-01

    Uncertainty and sensitivity analysis techniques based on Latin hypercube sampling, partial correlation analysis and stepwise regression analysis are used in an investigation with the MACCS model of the chronic exposure pathways associated with a severe accident at a nuclear power station. The primary purpose of this study is to provide guidance on the variables to be considered in future review work to reduce the uncertainty in the important variables used in the calculation of reactor accident consequences. The effects of 75 imprecisely known input variables on the following reactor accident consequences are studied: crop growing season dose, crop long-term dose, water ingestion dose, milk growing season dose, long-term groundshine dose, long-term inhalation dose, total food pathways dose, total ingestion pathways dose, total long-term pathways dose, total latent cancer fatalities, area-dependent cost, crop disposal cost, milk disposal cost, population-dependent cost, total economic cost, condemnation area, condemnation population, crop disposal area and milk disposal area. When the predicted variables are considered collectively, the following input variables were found to be the dominant contributors to uncertainty: dry deposition velocity, transfer of cesium from animal feed to milk, transfer of cesium from animal feed to meat, ground concentration of Cs-134 at which the disposal of milk products will be initiated, transfer of Sr-90 from soil to legumes, maximum allowable ground concentration of Sr-90 for production of crops, fraction of cesium entering surface water that is consumed in drinking water, groundshine shielding factor, scale factor defining resuspension, dose reduction associated with decontamination, and ground concentration of 1-131 at which disposal of crops will be initiated due to accidents that occur during the growing season.

  3. The acute and sub-chronic exposures of goldfish to naphthenic acids induce different host defense responses.

    Hagen, Mariel O; Garcia-Garcia, Erick; Oladiran, Ayoola; Karpman, Matthew; Mitchell, Scott; El-Din, Mohamed Gamal; Martin, Jonathan W; Belosevic, Miodrag

    2012-03-01

    Naphthenic acids (NAs) are believed to be the major toxic component in oil sands process-affected water (OSPW) produced by the oil sands mining industry in Northern Alberta, Canada. We recently reported that oral exposure to NAs alters mammalian immune responses, but the effect of OSPW or NAs on the immune mechanisms of aquatic organisms has not been fully elucidated. We analyzed the effects of acute and sub-chronic NAs exposures on goldfish immune responses by measuring the expression of three pro-inflammatory cytokine genes, antimicrobial functions of macrophages, and host defense after challenge with a protozoan pathogen (Trypanosoma carassii). One week after NAs exposure, fish exhibited increased expression of pro-inflammatory cytokines (IFNγ, IL-1β1, TNF-α2) in the gills, kidney and spleen. Primary macrophages from fish exposed to NAs for one week, exhibited increased production of nitric oxide and reactive oxygen intermediates. Goldfish exposed for one week to 20 mg/L NAs were more resistant to infection by T. carassii. In contrast, sub-chronic exposure of goldfish (12 weeks) to NAs resulted in decreased expression of pro-inflammatory cytokines in the gills, kidney and spleen. The sub-chronic exposure to NAs reduced the ability of goldfish to control the T. carassii infection, exemplified by a drastic increase in fish mortality and increased blood parasite loads. This is the first report analyzing the effects of OSPW contaminants on the immune system of aquatic vertebrates. We believe that the bioassays depicted in this work will be valuable tools for analyzing the efficacy of OSPW remediation techniques and assessment of diverse environmental pollutants. PMID:22227375

  4. Gene expression and pathologic alterations in juvenile rainbow trout due to chronic dietary TCDD exposure

    Highlights: •First report of the effects of dietary TCDD in juvenile trout smaller than 20 g. •TCDD uptake was estimated using published models and confirmed by GC. •First report of dietary TCDD-induced lesions in nasal epithelium in any species. •Several useful biomarkers are identified from microarray-based transcriptomics analysis. -- Abstract: The goal of this project was to use functional genomic methods to identify molecular biomarkers as indicators of the impact of TCDD exposure in rainbow trout. Specifically, we investigated the effects of chronic dietary TCDD exposure on whole juvenile rainbow trout global gene expression associated with histopathological analysis. Juvenile rainbow trout were fed Biodiet starter with TCDD added at 0, 0.1, 1, 10 and 100 ppb (ng TCDD/g food), and fish were sampled from each group at 7, 14, 28 and 42 days after initiation of feeding. 100 ppb TCDD caused 100% mortality at 39 days. Fish fed with 100 ppb TCDD food had TCDD accumulation of 47.37 ppb (ng TCDD/g fish) in whole fish at 28 days. Histological analysis from TCDD-treated trout sampled from 28 and 42 days revealed that obvious lesions were found in skin, oropharynx, liver, gas bladder, intestine, pancreas, nose and kidney. In addition, TCDD caused anemia in peripheral blood, decreases in abdominal fat, increases of remodeling of fin rays, edema in pericardium and retrobulbar hemorrhage in the 100 ppb TCDD-treated rainbow trout compared to the control group at 28 days. Dose- and time-dependent global gene expression analyses were performed using the cGRASP 16,000 (16K) cDNA microarray. TCDD-responsive whole body transcripts identified in the microarray experiments have putative functions involved in various biological processes including growth, cell proliferation, metabolic process, and immune system processes. Nine microarray-identified genes were selected for QPCR validation. CYP1A3 and CYP1A1 were common up-regulated genes and HBB1 was a common down

  5. Gene expression and pathologic alterations in juvenile rainbow trout due to chronic dietary TCDD exposure

    Liu, Qing [Department of Biological Sciences, University of Wisconsin-Milwaukee, Lapham Hall, 3209 N. Maryland Ave., Milwaukee, WI 53211 (United States); School of Freshwater Sciences, University of Wisconsin-Milwaukee, 600 E Greenfield Ave, Milwaukee, WI 53204 (United States); Rise, Matthew L. [Ocean Sciences Centre, Memorial University of Newfoundland, 1 Marine Lab Road, St. John' s, NL, A1C 5S7 (Canada); Spitsbergen, Jan M. [Department of Microbiology, Oregon State University, 220 Nash Hall, Corvallis, OR 97331 (United States); Hori, Tiago S. [Ocean Sciences Centre, Memorial University of Newfoundland, 1 Marine Lab Road, St. John' s, NL, A1C 5S7 (Canada); Mieritz, Mark; Geis, Steven [Wisconsin State Laboratory of Hygiene, 465 Henry Mall, Madison, WI 53706 (United States); McGraw, Joseph E. [School of Pharmacy, Concordia University Wisconsin, 12800 North Lake Shore Drive, Mequon, WI 53097 (United States); Goetz, Giles [School of Aquatic and Fishery Sciences, University of Washington, 1122 Northeast Boat Street, Seattle, WA 98195 (United States); Larson, Jeremy; Hutz, Reinhold J. [Department of Biological Sciences, University of Wisconsin-Milwaukee, Lapham Hall, 3209 N. Maryland Ave., Milwaukee, WI 53211 (United States); Carvan, Michael J., E-mail: carvanmj@uwm.edu [Department of Biological Sciences, University of Wisconsin-Milwaukee, Lapham Hall, 3209 N. Maryland Ave., Milwaukee, WI 53211 (United States); School of Freshwater Sciences, University of Wisconsin-Milwaukee, 600 E Greenfield Ave, Milwaukee, WI 53204 (United States)

    2013-09-15

    Highlights: •First report of the effects of dietary TCDD in juvenile trout smaller than 20 g. •TCDD uptake was estimated using published models and confirmed by GC. •First report of dietary TCDD-induced lesions in nasal epithelium in any species. •Several useful biomarkers are identified from microarray-based transcriptomics analysis. -- Abstract: The goal of this project was to use functional genomic methods to identify molecular biomarkers as indicators of the impact of TCDD exposure in rainbow trout. Specifically, we investigated the effects of chronic dietary TCDD exposure on whole juvenile rainbow trout global gene expression associated with histopathological analysis. Juvenile rainbow trout were fed Biodiet starter with TCDD added at 0, 0.1, 1, 10 and 100 ppb (ng TCDD/g food), and fish were sampled from each group at 7, 14, 28 and 42 days after initiation of feeding. 100 ppb TCDD caused 100% mortality at 39 days. Fish fed with 100 ppb TCDD food had TCDD accumulation of 47.37 ppb (ng TCDD/g fish) in whole fish at 28 days. Histological analysis from TCDD-treated trout sampled from 28 and 42 days revealed that obvious lesions were found in skin, oropharynx, liver, gas bladder, intestine, pancreas, nose and kidney. In addition, TCDD caused anemia in peripheral blood, decreases in abdominal fat, increases of remodeling of fin rays, edema in pericardium and retrobulbar hemorrhage in the 100 ppb TCDD-treated rainbow trout compared to the control group at 28 days. Dose- and time-dependent global gene expression analyses were performed using the cGRASP 16,000 (16K) cDNA microarray. TCDD-responsive whole body transcripts identified in the microarray experiments have putative functions involved in various biological processes including growth, cell proliferation, metabolic process, and immune system processes. Nine microarray-identified genes were selected for QPCR validation. CYP1A3 and CYP1A1 were common up-regulated genes and HBB1 was a common down

  6. Chronic Exposure to Deoxynivalenol Has No Influence on the Oral Bioavailability of Fumonisin B1 in Broiler Chickens

    Antonissen, Gunther; Devreese, Mathias; Van Immerseel, Filip; De Baere, Siegrid; Hessenberger, Sabine; Martel, An; Croubels, Siska

    2015-01-01

    Both deoxynivalenol (DON) and fumonisin B1 (FB1) are common contaminants of feed. Fumonisins (FBs) in general have a very limited oral bioavailability in healthy animals. Previous studies have demonstrated that chronic exposure to DON impairs the intestinal barrier function and integrity, by affecting the intestinal surface area and function of the tight junctions. This might influence the oral bioavailability of FB1, and possibly lead to altered toxicity of this mycotoxin. A toxicokinetic study was performed with two groups of 6 broiler chickens, which were all administered an oral bolus of 2.5 mg FBs/kg BW after three-week exposure to either uncontaminated feed (group 1) or feed contaminated with 3.12 mg DON/kg feed (group 2). No significant differences in toxicokinetic parameters of FB1 could be demonstrated between the groups. Also, no increased or decreased body exposure to FB1 was observed, since the relative oral bioavailability of FB1 after chronic DON exposure was 92.2%. PMID:25690690

  7. Uranium microdistribution in renal cortex of rats after chronic exposure: a study by secondary ion mass spectrometry microscopy.

    Tessier, Christine; Suhard, David; Rebière, François; Souidi, Maâmar; Dublineau, Isabelle; Agarande, Michelle

    2012-02-01

    For a few years, the biological effects on ecosystems and the public of the bioaccumulation of radionuclides in situations of chronic exposures have been studied. This work, in keeping with the ENVIRHOM French research program, presents the uranium microdistribution by secondary ion mass spectrometry (SIMS) technique in the renal cortex of rats following chronic exposure to this low level element in the drinking water (40 mg/L) as a function to exposure duration (6, 9, 12, and 18 months). The SIMS mass spectra and 238U+ ion images produced with a SIMS CAMECA 4F-E7 show the kinetic of uranium accumulation in the different structures of the kidney. For the rats contaminated up to 12 months, the radioelement is mainly fixed in the proximal tubules; then after 18 exposure months, uranium is detected in all the segments of the nephron. This work has also shown that ion microscopy is an analytical method to detect trace elements and give elemental cartography at the micrometer scale. PMID:22217926

  8. Developmental effects induced by chronic and prolonged exposure of chicken embryos to 900 MHz GSM base station radiation

    Interference from base station radiation with embryonic development was investigated by chronic and prolonged exposure of developing chicken embryos. The latter were exposed under a 900 MHz GSM base station radiating microwaves at recommended safety level, i.e., 41 V/m. Total death rate was 7.7 times higher among radiation exposed embryos (78.5%) than among sham exposures (10.2%). Radiation exposure was associated with delayed hatching (3.2 days) and slightly but significantly increased (P<0.01) weight of hatchings. These finding indicated that base station radiation can induce lethal effect, as well as developmental retardation. They arouse questioning as to the adequacy of current safety guidelines. (author)

  9. Zebrafish gene expression, histology, blood domoic acid level, and behavioral data (Effects of Chronic Domoic Acid Exposure on Gene Expression in the Vertebrate CNS.)

    National Oceanic and Atmospheric Administration, Department of Commerce — The potential impacts of chronic algal toxin exposure have long been a concern. One HAB toxin, domoic acid (DA), is a potent neurotoxin that interacts with the...

  10. Expression of Glutamatergic Genes in Healthy Humans across 16 Brain Regions; Altered Expression in the Hippocampus after Chronic Exposure to Alcohol or Cocaine

    Enoch, Mary-Anne; Rosser, Alexandra A.; Zhou, Zhifeng; Mash, Deborah C; Yuan, Qiaoping; Goldman, David

    2014-01-01

    We analyzed global patterns of expression in genes related to glutamatergic neurotransmission (glutamatergic genes) in healthy human adult brain before determining the effects of chronic alcohol and cocaine exposure on gene expression in the hippocampus.

  11. Effects of sub-chronic exposure to SO{sub 2} on lipid and carbohydrate metabolism in rats

    Lovati, M.R. [Institute of Pharmacological Sciences, Milan (Italy); Manzoni, C. [Institute of Pharmacological Sciences, Milan (Italy); Daldossi, M. [Institute of Pharmacological Sciences, Milan (Italy); Spolti, S. [Institute of Pharmacological Sciences, Milan (Italy); Sirtori, C.R. [Institute of Pharmacological Sciences, Milan (Italy)

    1996-01-01

    Sulfur dioxide (SO{sub 2}) is a ubiquitous air pollutant, present in low concentrations in the urban air, and in higher concentrations in the working environment. While toxicological reports on SO{sub 2} have extensively dealt with the pulmonary system, essentially no data are available on the effects of chronic exposure to this pollutant on intermediary metabolism, although some biochemical changes in lipid metabolism have been detected. The present investigation was aimed at evaluating the effects of sub-chronic exposure to SO{sub 2} on concentrations of serum lipids/lipoproteins and on glucose metabolism, in animal models of hypercholesterolemia and diabetes. A specially designed controlinert atmosphere chamber was used, where male Sprague-Dawley rats fed on either standard or cholesterol enriched (HC) diets, as well as streptozotocin diabetics, were exposed to SO{sub 2} at 5 and 10 ppm, 24 h per day for 14 days. In rats, both on a standard diet and on a HC regimen, SO{sub 2} exposure determined a significant dose-dependent increase in plasma triglycerides, up to +363% in the 10 ppm HC exposed animals. This same gas concentration significantly reduced HDL cholesterol levels. In contrast, exposure of diabetic animals to 10 ppm SO{sub 2} resulted in a fall (-41%) of plasma and liver triglycerides and in a concomitant increase (+62%) of plasma HDL cholesterol. This discrepancy could apparently be related to diverging effects of SO{sub 2} exposure on plasma insulin levels in the different animal groups. Kinetic analyses of triglyceride synthesis carried out in rats on a standard diet revealed, in exposed animals, a significant reduction in the secretory rate, in spite of the concomitant hypertriglyceridemia. These findings suggest that SO{sub 2} exposure can markedly modify major lipid and glycemic indices, also indicating a differential response in normo/hyperlipidemic versus diabetic animals. (orig.)

  12. Effects of chronic uranium internal exposure on mortality: Results of a pilot study among French nuclear workers

    Background: This article presents the mortality data compiled among a cohort of workers at risk of internal uranium exposure and discusses the extent to which this exposure might differentiate them from other nuclear workers. Methods: The cohort consisted of 2897 Areva-NC-Pierrelatte plant workers, followed from 1 January 1968 through 31 December 2006 (79,892 person-years). Mortality was compared with that of the French population, by calculating Standardized Mortality Ratios (SMR) and 95 % confidence intervals (CI95 %). External radiation exposure was reconstructed using external dosimetry archives. Internal uranium exposure was assessed using a plant-specific job-exposure-matrix, considering six types of uranium compounds according to their nature (natural and reprocessed uranium [RPU] and solubility [fast-F, moderate-M, and slow-S]). Exposure-effect analyses were performed for causes of death known to be related to external radiation exposure (all cancers and circulatory system diseases) and cancer of uranium target-organs (lung and hematopoietic and lymphatic tissues, HLT). Results: A significant deficit of mortality from all causes (SMR = 0.58; CI95% [0.53-0.63]), all cancers (SMR = 0.72; CI95% [0.63-0.82]) and smoking related cancers was observed. Non-significant 30 %-higher increase of mortality was observed for cancer of pleura (SMR = 2.32; CI95% [0.75-5.41]), rectum and HLT, notably non-Hodgkin's lymphoma (SMR = 1.38; CI95% [0.63-2.61]) and chronic lymphoid leukemia (SMR = 2.36; CI95% [0.64-6.03]). No exposure-effect relationship was found with external radiation cumulative dose. A significant exposure-effect relationship was observed for slowly soluble uranium, particularly RPU, which was associated with an increase in mortality risk reaching 8 to 16 % per unit of cumulative exposure score and 10 to 15 % per year of exposure duration. Conclusion: The Areva-NC-Pierrelatte workers cohort presents a non-significant over-mortality from HLT cancers, notably of

  13. Metabolism of Mycotoxins, Intracellular Functions of Vitamin B12, and Neurological Manifestations in Patients with Chronic Toxigenic Mold Exposures. A Review

    Ebere C. Anyanwu; Mohammed Morad; Campbell, Andrew W.

    2004-01-01

    This paper evaluates the possible reasons for consistent vitamin B12 deficiency in chronic toxigenic mold exposures and the synergistic relationships with the possible mycotoxic effects on one-carbon metabolism that lead to the manifestations of clinical neuropathological symptomology. Vitamins are first defined in general and the nutritional sources of vitamin B12 are evaluated in particular. Since patients with chronic exposures to toxigenic molds manifest vitamin B12 deficiencies, the role...

  14. Hair analysis following chronic smoked-drugs-of-abuse exposure in adults and their toddler: a case report

    Papaseit Esther

    2011-12-01

    Full Text Available Abstract Introduction Over the past two decades, the study of chronic cocaine and crack cocaine exposure in the pediatric population has been focused on the potential adverse effects, especially in the prenatal period and early childhood. Non-invasive biological matrices have become an essential tool for the assessment of a long-term history of drug of abuse exposure. Case report We analyze the significance of different biomarker values in hair after chronic crack exposure in a two-year-old Caucasian girl and her parents, who are self-reported crack smokers. The level of benzoylecgonine, the principal metabolite of cocaine, was determined in segmented hair samples (0 cm to 3 cm from the scalp, and > 3 cm from the scalp following washing to exclude external contamination. Benzoylecgonine was detectable in high concentrations in the child's hair, at 1.9 ng/mg and 7.04 ng/mg, respectively. Benzoylecgonine was also present in the maternal and paternal hair samples at 7.88 ng/mg and 6.39 ng/mg, and 13.06 ng/mg and 12.97 ng/mg, respectively. Conclusion Based on the data from this case and from previously published poisoning cases, as well as on the experience of our research group, we conclude that, using similar matrices for the study of chronic drug exposure, children present with a higher cocaine concentration in hair and they experience more serious deleterious acute effects, probably due to a different and slower cocaine metabolism. Consequently, children must be not exposed to secondhand crack smoke under any circumstance.

  15. Accumulation and effects of Cr(VI) in Japanese medaka (Oryzias latipes) during chronic dissolved and dietary exposures.

    Chen, Hongxing; Mu, Lei; Cao, Jinling; Mu, Jingli; Klerks, Paul L; Luo, Yongju; Guo, Zhongbao; Xie, Lingtian

    2016-07-01

    Chromium (Cr) is an essential metal and a nutritional supplement for both human and agricultural uses. It is also a pollutant from a variety of industrial uses. These uses can lead to elevated Cr levels in aquatic environments, where it can enter and affect aquatic organisms. Its accumulation and subsequent effects in fish have received relatively little attention, especially for chronic exposure. In the present study, Japanese medaka were chronically exposed to dissolved or dietary Cr(VI) for 3 months. Cr accumulation in liver, gills, intestine, and brain was evaluated. Effects on the antioxidant system, nervous system (acetylcholinesterase, AChE), digestive system (α-glucosidase, α-Glu), and tissue histology (liver and gills) were also assessed. Cr accumulation was observed in the intestine and liver of fish exposed to Cr-contaminated brine shrimp. However, chronic dissolved Cr exposure led to significant Cr accumulation in all organs tested. Analysis of the subcellular distribution of Cr in medaka livers revealed that 37% of the Cr was present in the heat stable protein fraction. The dissolved Cr exposure had pronounced effects on the antioxidant system in the liver, with an elevated ratio of reduced glutathione/oxidized glutathione (GSH/GSSG) and decreases in GSH and glutathione S-transferase (GST). The α-Glu activity in the intestine was significantly inhibited. In addition, Cr exposure caused histopathological alterations in the gills and liver. In general, the effects of dietary Cr were relatively minor, possible due to the much lower accumulation in the fish. Our results imply that Japanese medaka accumulate Cr mainly via uptake of dissolved Cr(VI). PMID:27162070

  16. Chronic environmental exposure to lead affects semen quality in a Mexican men population

    Morán-Martínez, Javier; Carranza-Rosales, Pilar; Morales-Vallarta, Mario; A. Heredia-Rojas, José; Bassol-Mayagoitia, Susana; Denys Betancourt-Martínez, Nadia; M. Cerda-Flores, Ricardo

    2013-01-01

    Background: Male infertility is affected by several factors. Lead is one of the heavy metals more bioavailable than usually modifies the sperm quality in humans. Objective: The aim of this study was to establish the role of lead in semen quality in environmentally exposed men. Materials and Methods: Semen and blood samples were obtained from two groups: the exposed group (EG=20) and the non-exposed group (NEG=27). Two semen aliquots were used, one to evaluate spermatic quality and the other for lead determination. Blood (PbB) and semen lead (PbS) determination was performed by atomic absorption spectrophotometry. Results: The PbB concentration was significantly greater in the EG, 10.10±0.97 µgdL-1 than in the NEG, 6.42±0.38 µgdL-1 (p<0.01), as well as the PbS concentration, with 3.28±0.35 and 1.76±0.14µgdL-1 in the EG and NEG respectively (p=0.043). A significant correlation between PbS and PbB concentration in the EG was found (r=0.573, p=0.038). Overall, the spermatic quality was lower in the EG than in the NEG. Specifically, there were significant differences in the spermatic concentration [EG=43.98±6.26 and NEG=68.78±8.51X106 cellmL-1 (p<0.01)], motility [EG=49±7 and NEG=67±4% (p=0.029)], viability [EG=36.32±3.59 and NEG=72.12±1.91% (p<0.01)] and abnormal morphology [EG=67±18 and NEG=32±12% (p<0.01)]. In the immature germ cells (IGC) concentration differences were found only for A cells (EG=8.1±1.1x100 and NEG=3.2±1.9X100 spermatozoa) (p<0.01) and for Sab cells (EG=3.4±2.2x100 and NEG=1.1±1.0X100 spermatozoa) (p=0.041). Conclusion: These results suggest that chronic environmental exposure to low levels of lead adversely affect the spermatic quality. PMID:24639755

  17. Neuropsychological effects of chronic low-dose exposure to polychlorinated biphenyls (PCBs: A cross-sectional study

    Klett Martin

    2005-10-01

    Full Text Available Abstract Background Exposure to indoor air of private or public buildings contaminated with polychlorinated biphenyls (PCBs has raised health concerns in long-term users. This exploratory neuropsychological group study investigated the potential adverse effects of chronic low-dose exposure to specific air-borne low chlorinated PCBs on well-being and behavioral measures in adult humans. Methods Thirty employees exposed to indoor air contaminated with PCBs from elastic sealants in a school building were compared to 30 non-exposed controls matched for education and age, controlling for gender (age range 37–61 years. PCB exposure was verified by external exposure data and biological monitoring (PCB 28, 101, 138, 153, 180. Subjective complaints, learning and memory, executive function, and visual-spatial function was assessed by standardized neuropsychological testing. Since exposure status depended on the use of contaminated rooms, an objectively exposed subgroup (N = 16; PCB 28 = 0.20 μg/l; weighted exposure duration 17.9 ± 7 years was identified and compared with 16 paired controls. Results Blood analyses indicated a moderate exposure effect size (d relative to expected background exposure for total PCB (4.45 ± 2.44 μg/l; d = 0.4. A significant exposure effect was found for the low chlorinated PCBs 28 (0.28 ± 0.25 μg/l; d = 1.5 and 101 (0.07 ± 0.09 μg/l; d = 0.7. Although no neuropsychological effects exceeded the adjusted significance level, estimation statistics showed elevated effect sizes for several variables. The objectively exposed subgroup showed a trend towards increased subjective attentional and emotional complaints (tiredness and slowing of practical activities, emotional state as well as attenuated attentional performance (response shifting and alertness in a cued reaction task. Conclusion Chronic inhalation of low chlorinated PCBs that involved elevated blood levels was associated with a subtle attenuation of emotional well

  18. Injury to the blood-testis barrier after low-dose-rate chronic radiation exposure in mice

    Exposure to ionising radiation induces male infertility, accompanied by increasing permeability of the blood-testis barrier. However, the effect on male fertility by low-dose-rate chronic radiation has not been investigated. In this study, the effects of low-dose-rate chronic radiation on male mice were investigated by measuring the levels of tight-junction-associated proteins (ZO-1 and occludin-1), Niemann-Pick disease type 2 protein (NPC-2) and anti-sperm antibody (AsAb) in serum. BALB/c mice were exposed to low-dose-rate radiation (3.49 mGy h-1) for total exposures of 0.02 (6 h), 0.17 (2 d) and 1.7 Gy (21 d). Based on histological examination, the diameter and epithelial depth of seminiferous tubules were significantly decreased in 1.7-Gy-irradiated mice. Compared with those of the non-irradiated group, 1.7-Gy-irradiated mice showed significantly decreased ZO-1, occludin-1 and NPC-2 protein levels, accompanied with increased serum AsAb levels. These results suggest potential blood-testis barrier injury and immune infertility in male mice exposed to low-dose-rate chronic radiation. (authors)

  19. Continuing Exposure to Low-Dose Nonylphenol Aggravates Adenine-Induced Chronic Renal Dysfunction and Role of Rosuvastatin Therapy

    Yen Chia-Hung

    2012-07-01

    Full Text Available Abstract Background Nonylphenol (NP, an environmental organic compound, has been demonstrated to enhance reactive-oxygen species (ROS synthesis. Chronic exposure to low-dose adenine (AD has been reported to induce chronic kidney disease (CKD. Methods In this study, we tested the hypothesis that chronic exposure to NP will aggravate AD-induced CKD through increasing generations of inflammation, ROS, and apoptosis that could be attenuated by rosuvastatin. Fifty male Wistar rats were equally divided into group 1 (control, group 2 (AD in fodder at a concentration of 0.25%, group 3 (NP: 2 mg/kg/day, group 4 (combined AD & NP, and group 5 (AD-NP + rosuvastatin: 20 mg/kg/day. Treatment was continued for 24 weeks for all animals before being sacrificed. Results By the end of 24 weeks, serum blood urea nitrogen (BUN and creatinine levels were increased in group 4 than in groups 1–3, but significantly reduced in group 5 as compared with group 4 (all p  Conclusion NP worsened AD-induced CKD that could be reversed by rosuvastatin therapy.

  20. Chronic occupational exposure to arsenic induces carcinogenic gene signaling networks and neoplastic transformation in human lung epithelial cells

    Chronic arsenic exposure remains a human health risk; however a clear mode of action to understand gene signaling-driven arsenic carcinogenesis is currently lacking. This study chronically exposed human lung epithelial BEAS-2B cells to low-dose arsenic trioxide to elucidate cancer promoting gene signaling networks associated with arsenic-transformed (B-As) cells. Following a 6 month exposure, exposed cells were assessed for enhanced cell proliferation, colony formation, invasion ability and in vivo tumor formation compared to control cell lines. Collected mRNA was subjected to whole genome expression microarray profiling followed by in silico Ingenuity Pathway Analysis (IPA) to identify lung carcinogenesis modes of action. B-As cells displayed significant increases in proliferation, colony formation and invasion ability compared to BEAS-2B cells. B-As injections into nude mice resulted in development of primary and secondary metastatic tumors. Arsenic exposure resulted in widespread up-regulation of genes associated with mitochondrial metabolism and increased reactive oxygen species protection suggesting mitochondrial dysfunction. Carcinogenic initiation via reactive oxygen species and epigenetic mechanisms was further supported by altered DNA repair, histone, and ROS-sensitive signaling. NF-κB, MAPK and NCOR1 signaling disrupted PPARα/δ-mediated lipid homeostasis. A ‘pro-cancer’ gene signaling network identified increased survival, proliferation, inflammation, metabolism, anti-apoptosis and mobility signaling. IPA-ranked signaling networks identified altered p21, EF1α, Akt, MAPK, and NF-κB signaling networks promoting genetic disorder, altered cell cycle, cancer and changes in nucleic acid and energy metabolism. In conclusion, transformed B-As cells with their whole genome expression profile provide an in vitro arsenic model for future lung cancer signaling research and data for chronic arsenic exposure risk assessment. Highlights: ► Chronic As2O3

  1. Chronic occupational exposure to arsenic induces carcinogenic gene signaling networks and neoplastic transformation in human lung epithelial cells

    Stueckle, Todd A., E-mail: tstueckle@hsc.wvu.edu [Department of Basic Pharmaceutical Sciences, West Virginia University, Morgantown, WV 26506 (United States); Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, WV 26505 (United States); Lu, Yongju, E-mail: yongju6@hotmail.com [Department of Basic Pharmaceutical Sciences, West Virginia University, Morgantown, WV 26506 (United States); Davis, Mary E., E-mail: mdavis@wvu.edu [Department of Physiology, West Virginia University, Morgantown, WV 26506 (United States); Wang, Liying, E-mail: lmw6@cdc.gov [Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, WV 26505 (United States); Jiang, Bing-Hua, E-mail: bhjiang@jefferson.edu [Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA 19107 (United States); Holaskova, Ida, E-mail: iholaskova@hsc.wvu.edu [Department of Microbiology, Immunology and Cell Biology, West Virginia University, Morgantown, WV 26506 (United States); Schafer, Rosana, E-mail: rschafer@hsc.wvu.edu [Department of Microbiology, Immunology and Cell Biology, West Virginia University, Morgantown, WV 26506 (United States); Barnett, John B., E-mail: jbarnett@hsc.wvu.edu [Department of Microbiology, Immunology and Cell Biology, West Virginia University, Morgantown, WV 26506 (United States); Rojanasakul, Yon, E-mail: yrojan@hsc.wvu.edu [Department of Basic Pharmaceutical Sciences, West Virginia University, Morgantown, WV 26506 (United States)

    2012-06-01

    Chronic arsenic exposure remains a human health risk; however a clear mode of action to understand gene signaling-driven arsenic carcinogenesis is currently lacking. This study chronically exposed human lung epithelial BEAS-2B cells to low-dose arsenic trioxide to elucidate cancer promoting gene signaling networks associated with arsenic-transformed (B-As) cells. Following a 6 month exposure, exposed cells were assessed for enhanced cell proliferation, colony formation, invasion ability and in vivo tumor formation compared to control cell lines. Collected mRNA was subjected to whole genome expression microarray profiling followed by in silico Ingenuity Pathway Analysis (IPA) to identify lung carcinogenesis modes of action. B-As cells displayed significant increases in proliferation, colony formation and invasion ability compared to BEAS-2B cells. B-As injections into nude mice resulted in development of primary and secondary metastatic tumors. Arsenic exposure resulted in widespread up-regulation of genes associated with mitochondrial metabolism and increased reactive oxygen species protection suggesting mitochondrial dysfunction. Carcinogenic initiation via reactive oxygen species and epigenetic mechanisms was further supported by altered DNA repair, histone, and ROS-sensitive signaling. NF-κB, MAPK and NCOR1 signaling disrupted PPARα/δ-mediated lipid homeostasis. A ‘pro-cancer’ gene signaling network identified increased survival, proliferation, inflammation, metabolism, anti-apoptosis and mobility signaling. IPA-ranked signaling networks identified altered p21, EF1α, Akt, MAPK, and NF-κB signaling networks promoting genetic disorder, altered cell cycle, cancer and changes in nucleic acid and energy metabolism. In conclusion, transformed B-As cells with their whole genome expression profile provide an in vitro arsenic model for future lung cancer signaling research and data for chronic arsenic exposure risk assessment. Highlights: ► Chronic As{sub 2}O

  2. Exposure to daily ambient particulate polycyclic aromatic hydrocarbons and cough occurrence in adult chronic cough patients: A longitudinal study

    Anyenda, Enoch Olando; Higashi, Tomomi; Kambayashi, Yasuhiro; Thao, Nguyen Thi Thu; Michigami, Yoshimasa; Fujimura, Masaki; Hara, Johsuke; Tsujiguchi, Hiromasa; Kitaoka, Masami; Asakura, Hiroki; Hori, Daisuke; Yamada, Yohei; Hayashi, Koichiro; Hayakawa, Kazuichi; Nakamura, Hiroyuki

    2016-09-01

    The specific components of airborne particulates responsible for adverse health effects have not been conclusively identified. We conducted a longitudinal study on 88 adult patients with chronic cough to evaluate whether exposure to daily ambient levels of particulate polycyclic aromatic hydrocarbons (PAH) has relationship with cough occurrence. Study participants were recruited at Kanazawa University Hospital, Japan and were physician-diagnosed to at least have asthma, cough variant asthma and/or atopic cough during 4th January to 30th June 2011. Daily cough symptoms were collected by use of cough diaries and simultaneously, particulate PAH content in daily total suspended particles collected on glass fiber filters were determined by high performance liquid chromatography coupled with fluorescence detector. Population averaged estimates of association between PAH exposure and cough occurrence for entire patients and subgroups according to doctor's diagnosis were performed using generalized estimating equations. Selected adjusted odds ratios for cough occurrence were 1.088 (95% confidence interval (CI): 1.031, 1.147); 1.209 (95% CI: 1.060, 1.379) per 1 ng/m3 increase for 2-day lag and 6-day moving average PAH exposure respectively. Likewise, 5 ring PAH had higher odds in comparison to 4 ring PAH. On the basis of doctor's diagnosis, non-asthma group had slightly higher odds ratio 1.127 (95% CI: 1.033, 1.228) per 1 ng/m3 increase in 2-day lag PAH exposure. Our findings suggest that ambient PAH exposure is associated with cough occurrence in adult chronic cough patients. The association may be stronger in non-asthma patients and even at low levels although there is need for further study with a larger sample size of respective diagnosis and inclusion of co-pollutants.

  3. Chronic exposure to low benzo[a]pyrene level causes neurodegenerative disease-like syndromes in zebrafish (Danio rerio).

    Gao, Dongxu; Wu, Meifang; Wang, Chonggang; Wang, Yuanchuan; Zuo, Zhenghong

    2015-10-01

    Previous epidemiological and animal studies report that exposure to environmental pollutant exposure links to neurodegenerative diseases such as Parkinson's disease and Alzheimer's disease. Benzo[a]pyrene (BaP), a neurotoxic polycyclic aromatic hydrocarbon, has been increasingly released into the environment during recent decades. So far, the role of BaP on the development of neurodegenerative diseases remaind unclear. This study aimed to determine whether chronic exposure to low dose BaP would cause neurodegenerative disease-like syndromes in zebrafish (Danio rerio). We exposed zebrafish, from early embryogenesis to adults, to environmentally relevant concentrations of BaP for 230 days. Our results indicated that BaP decreased the brain weight to body weight ratio, locomotor activity and cognitive ability; induced the loss of dopaminergic neurons; and resulted in neurodegeneration. In addition, obvious cell apoptosis in the brain was found. Furthermore, the neurotransmitter levels of dopamine and 3,4-dihydroxyphenylacetic acid, the mRNA levels of the genes encoding dopamine transporter, Parkinson protein 7, phosphatase and tensin-induced putative kinase 1, ubiquitin carboxy-terminal hydrolase L1, leucine-rich repeat serine/threonine kinase 2, amyloid precursor protein b, presenilin 1 and presenilin 2 were significantly down-regulated by BaP exposure. These findings suggest that chronic exposure to low dose BaP could cause the behavioral, neuropathological, neurochemical, and genetic features of neurodegenerative diseases. This study provides clues that BaP may constitute an important environmental risk factor for neurodegenerative diseases in humans. PMID:26349946

  4. Using expression profiling to understand the effects of chronic cadmium exposure on MCF-7 breast cancer cells.

    Zelmina Lubovac-Pilav

    Full Text Available Cadmium is a metalloestrogen known to activate the estrogen receptor and promote breast cancer cell growth. Previous studies have implicated cadmium in the development of more malignant tumors; however the molecular mechanisms behind this cadmium-induced malignancy remain elusive. Using clonal cell lines derived from exposing breast cancer cells to cadmium for over 6 months (MCF-7-Cd4, -Cd6, -Cd7, -Cd8 and -Cd12, this study aims to identify gene expression signatures associated with chronic cadmium exposure. Our results demonstrate that prolonged cadmium exposure does not merely result in the deregulation of genes but actually leads to a distinctive expression profile. The genes deregulated in cadmium-exposed cells are involved in multiple biological processes (i.e. cell growth, apoptosis, etc. and molecular functions (i.e. cadmium/metal ion binding, transcription factor activity, etc.. Hierarchical clustering demonstrates that the five clonal cadmium cell lines share a common gene expression signature of breast cancer associated genes, clearly differentiating control cells from cadmium exposed cells. The results presented in this study offer insights into the cellular and molecular impacts of cadmium on breast cancer and emphasize the importance of studying chronic cadmium exposure as one possible mechanism of promoting breast cancer progression.

  5. Risk Analysis of Acute Or Chronic Exposure to Arsenic of the Inhabitants in a District of Buenos Aires, Argentina

    Cristina Vázquez

    2016-09-01

    Full Text Available The arsenic occurrence in the water constitutes a serious world health concern due to its toxicity. Depending on the intensity and duration of exposure, this element can be acutely lethal or may have a wide range of health effects in humans and animals. In Argentina, the origin of arsenic is mainly natural, and related to different geological processes. The Argentinean concern about arsenic and its influence on human health dates back to the previous century. The disease ascribed to arsenic contamination was called ‘chronic regional endemic hydroarsenism’. It is produced by the consumption of water with high levels of this element. In our study, we focused in La Matanza district, a very populated site in the Buenos Aires Province. An increasing concern of the inhabitants of the area regarding health problems was detected. In order to establish a full view of arsenic exposure in the area, several matrices and targets were analyzed. As matrices, water and soil samples were analyzed. As targets, canine and human hair was studied. The aim of this study was to investigate acute and chronically exposure to arsenic of La Matanza inhabitants.

  6. Chronic copper exposure and fatty acid composition of the amphipod Dikerogammarus villosus: Results from a field study

    Field study allows assessment of long-term effects on fatty acid (FA) composition of organisms under chronic exposure to metals. One expected effect of copper is peroxidation of lipids and essentially polyunsaturated fatty acids (PUFA). FA analysis was established for the amphipod Dikerogammarus villosus subjected to different degrees of copper exposure (4-40 μg Cu L-1). A previous study in our team showed that this species regulates its body Cu concentration (106-135 mg Cu kg-1 dry weight). Despite the high capacity of bioaccumulation, the absence of a correlation between copper concentration in D. villosus and water prevents its use as bioindicator of copper pollution. Both sexes from the most polluted site showed the lowest total FA content, but the highest PUFA percent, mainly of the long-chained variety (C20-C22). Mechanisms leading to the prevention of lipid peroxidation in this species were discussed (metallothioneins and intracellular granules) and proposed with support from literature data. - Under chronic copper exposure, Dikerogammarus villosus loses in total fatty acids content but increases its essential ω3 and ω6 PUFA percent

  7. Chronic copper exposure and fatty acid composition of the amphipod Dikerogammarus villosus: Results from a field study

    Maazouzi, Chafik [Universite de Metz, Laboratoire Interactions Ecotoxicologie Biodiversite Ecosystemes (LIEBE), CNRS UMR 7146, Avenue General Delestraint, 57070 Metz (France)], E-mail: maazouzi@univ-metz.fr; Masson, Gerard [Universite de Metz, Laboratoire Interactions Ecotoxicologie Biodiversite Ecosystemes (LIEBE), CNRS UMR 7146, Avenue General Delestraint, 57070 Metz (France)], E-mail: masson1@univ-metz.fr; Izquierdo, Maria Soledad [Grupo de Investigacion en Acuicultura, ULPGC and ICCM, P.O. Box 56, 35200 Telde, Las Palmas de Gran Canaria (Spain)], E-mail: mizquierdo@dbio.ulpgc.es; Pihan, Jean-Claude [Universite de Metz, Laboratoire Interactions Ecotoxicologie Biodiversite Ecosystemes (LIEBE), CNRS UMR 7146, Avenue General Delestraint, 57070 Metz (France)], E-mail: pihan@univ-metz.fr

    2008-11-15

    Field study allows assessment of long-term effects on fatty acid (FA) composition of organisms under chronic exposure to metals. One expected effect of copper is peroxidation of lipids and essentially polyunsaturated fatty acids (PUFA). FA analysis was established for the amphipod Dikerogammarus villosus subjected to different degrees of copper exposure (4-40 {mu}g Cu L{sup -1}). A previous study in our team showed that this species regulates its body Cu concentration (106-135 mg Cu kg{sup -1} dry weight). Despite the high capacity of bioaccumulation, the absence of a correlation between copper concentration in D. villosus and water prevents its use as bioindicator of copper pollution. Both sexes from the most polluted site showed the lowest total FA content, but the highest PUFA percent, mainly of the long-chained variety (C20-C22). Mechanisms leading to the prevention of lipid peroxidation in this species were discussed (metallothioneins and intracellular granules) and proposed with support from literature data. - Under chronic copper exposure, Dikerogammarus villosus loses in total fatty acids content but increases its essential {omega}3 and {omega}6 PUFA percent.

  8. Impact of chronic cadmium exposure at environmental dose on escape behaviour in sea bass (Dicentrarchus labrax L.; Teleostei, Moronidae)

    The effect of chronic exposure to a low concentration (0.5 μg l-1) of cadmium ions was investigated on escape behaviour of sea bass, Dicentrarchus labrax, using video analysis. Observations were also performed on the microanatomy of lateral system neuromasts. When fish were exposed for 4 h per day over 8 days to the cadmium ions, most of both types of neuromasts observed remained intact. However, some of them presented damaged sensory maculae. Whereas before cadmium exposure, fish responded positively to nearly all the lateral system stimulations, after exposure they decreased by about 10% their positive responses to stimulations. From the 15th day after the beginning of cadmium exposure, neuromasts presented progressively less damage, cadmium accumulation in gills and scales decreased significantly and fish escape behaviour had recovered. This study presents a new concept in ecotoxicology: using behavioural change to reveal the effects of pollution levels, scarcely detectable by currently used techniques (physiological responses). - Cadmium exposure involved a significant bioaccumulation in fish scales, slight damage to the lateral line system and a significant decrease in fish escape behaviour

  9. Chronic pain relief after the exposure of nitrous oxide during dental treatment: longitudinal retrospective study

    Francisco Moreira Mattos Júnior

    2015-07-01

    Full Text Available The objective was to investigate the effect of nitrous/oxygen in chronic pain. Seventy-seven chronic pain patients referred to dental treatment with conscious sedation with nitrous oxide/oxygen had their records included in this research. Data were collected regarding the location and intensity of pain by the visual analogue scale before and after the treatment. Statistical analysis was performed comparing pre- and post-treatment findings. It was observed a remarkable decrease in the prevalence of pain in this sample (only 18 patients still had chronic pain, p < 0.001 and in its intensity (p < 0.001. Patients that needed fewer sessions received higher proportions of nitrous oxide/oxygen. Nitrous oxide may be a tool to be used in the treatment of chronic pain, and future prospective studies are necessary to understand the underlying mechanisms and the effect of nitrous oxide/oxygen in patients according to the pain diagnosis and other characteristics.

  10. Pulmonary sensitivity to ozone exposure in sedentary versus chronically trained, female rats

    U.S. Environmental Protection Agency — Pulmonary effects to ozone with rats that have chronically exercised or have been continuously sedentary. Also includes body composition of both groups throughout...

  11. Persistent modification of Na{sub v}1.9 following chronic exposure to insecticides and pyridostigmine bromide

    Nutter, Thomas J., E-mail: tnutter@dental.ufl.edu; Cooper, Brian Y., E-mail: bcooper@dental.ufl.edu

    2014-06-15

    Many veterans of the 1991 Gulf War (GW) returned from that conflict with a widespread chronic pain affecting deep tissues. Recently, we have shown that a 60 day exposure to the insecticides permethrin, chlorpyrifos, and pyridostigmine bromide (NTPB) had little influence on nociceptor action potential forming Na{sub v}1.8, but increased K{sub v}7 mediated inhibitory currents 8 weeks after treatment. Using the same exposure regimen, we used whole cell patch methods to examine whether the influences of NTPB could be observed on Na{sub v}1.9 expressed in muscle and vascular nociceptors. During a 60 day exposure to NTPB, rats exhibited lowered muscle pain thresholds and increased rest periods, but these measures subsequently returned to normal levels. Eight and 12 weeks after treatments ceased, DRG neurons were excised from the sensory ganglia. Whole cell patch studies revealed little change in voltage dependent activation and deactivation of Na{sub v}1.9, but significant increases in the amplitude of Na{sub v}1.9 were observed 8 weeks after exposure. Cellular studies, at the 8 week delay, revealed that NTPB also significantly prolonged action potential duration and afterhyperpolarization (22 °C). Acute application of permethrin (10 μM) also increased the amplitude of Na{sub v}1.9 in skin, muscle and vascular nociceptors. In conclusion, chronic exposure to Gulf War agents produced long term changes in the amplitude of Na{sub v}1.9 expressed in muscle and vascular nociceptors. The reported increases in K{sub v}7 amplitude may have been an adaptive response to increased Na{sub v}1.9, and effectively suppressed behavioral pain measures in the post treatment period. Factors that alter the balance between Na{sub v}1.9 and K{sub v}7 could release spontaneous discharge and produce chronic deep tissue pain. - Highlights: • Rats were treated 60 days with permethrin, chlorpyrifos and pyridostigmine bromide. • 8 weeks after treatments, Nav1.9 activation and deactivation were

  12. MAPK pathway activation by chronic lead-exposure increases vascular reactivity through oxidative stress/cyclooxygenase-2-dependent pathways

    Simões, Maylla Ronacher, E-mail: yllars@hotmail.com [Dept. of Physiological Sciences, Federal University of Espirito Santo, Vitória, ES CEP 29040-091 (Brazil); Department of Pharmacology, Universidad Autonoma de Madrid, Instituto de Investigación Hospital Universitario La Paz (IdiPAZ), Madrid (Spain); Aguado, Andrea [Department of Pharmacology, Universidad Autonoma de Madrid, Instituto de Investigación Hospital Universitario La Paz (IdiPAZ), Madrid (Spain); Fiorim, Jonaína; Silveira, Edna Aparecida; Azevedo, Bruna Fernandes; Toscano, Cindy Medice [Dept. of Physiological Sciences, Federal University of Espirito Santo, Vitória, ES CEP 29040-091 (Brazil); Zhenyukh, Olha; Briones, Ana María [Department of Pharmacology, Universidad Autonoma de Madrid, Instituto de Investigación Hospital Universitario La Paz (IdiPAZ), Madrid (Spain); Alonso, María Jesús [Dept. of Biochemistry, Physiology and Molecular Genetics, Universidad Rey Juan Carlos, Alcorcón (Spain); Vassallo, Dalton Valentim [Dept. of Physiological Sciences, Federal University of Espirito Santo, Vitória, ES CEP 29040-091 (Brazil); Health Science Center of Vitória-EMESCAM, Vitória, ES CEP 29045-402 (Brazil); Salaices, Mercedes, E-mail: mercedes.salaices@uam.es [Department of Pharmacology, Universidad Autonoma de Madrid, Instituto de Investigación Hospital Universitario La Paz (IdiPAZ), Madrid (Spain)

    2015-03-01

    Chronic exposure to low lead concentration produces hypertension; however, the underlying mechanisms remain unclear. We analyzed the role of oxidative stress, cyclooxygenase-2-dependent pathways and MAPK in the vascular alterations induced by chronic lead exposure. Aortas from lead-treated Wistar rats (1st dose: 10 μg/100 g; subsequent doses: 0.125 μg/100 g, intramuscular, 30 days) and cultured aortic vascular smooth muscle cells (VSMCs) from Sprague Dawley rats stimulated with lead (20 μg/dL) were used. Lead blood levels of treated rats attained 21.7 ± 2.38 μg/dL. Lead exposure increased systolic blood pressure and aortic ring contractile response to phenylephrine, reduced acetylcholine-induced relaxation and did not affect sodium nitroprusside relaxation. Endothelium removal and L-NAME left-shifted the response to phenylephrine more in untreated than in lead-treated rats. Apocynin and indomethacin decreased more the response to phenylephrine in treated than in untreated rats. Aortic protein expression of gp91(phox), Cu/Zn-SOD, Mn-SOD and COX-2 increased after lead exposure. In cultured VSMCs lead 1) increased superoxide anion production, NADPH oxidase activity and gene and/or protein levels of NOX-1, NOX-4, Mn-SOD, EC-SOD and COX-2 and 2) activated ERK1/2 and p38 MAPK. Both antioxidants and COX-2 inhibitors normalized superoxide anion production, NADPH oxidase activity and mRNA levels of NOX-1, NOX-4 and COX-2. Blockade of the ERK1/2 and p38 signaling pathways abolished lead-induced NOX-1, NOX-4 and COX-2 expression. Results show that lead activation of the MAPK signaling pathways activates inflammatory proteins such as NADPH oxidase and COX-2, suggesting a reciprocal interplay and contribution to vascular dysfunction as an underlying mechanisms for lead-induced hypertension. - Highlights: • Lead-exposure increases oxidative stress, COX-2 expression and vascular reactivity. • Lead exposure activates MAPK signaling pathway. • ROS and COX-2 activation by

  13. MAPK pathway activation by chronic lead-exposure increases vascular reactivity through oxidative stress/cyclooxygenase-2-dependent pathways

    Chronic exposure to low lead concentration produces hypertension; however, the underlying mechanisms remain unclear. We analyzed the role of oxidative stress, cyclooxygenase-2-dependent pathways and MAPK in the vascular alterations induced by chronic lead exposure. Aortas from lead-treated Wistar rats (1st dose: 10 μg/100 g; subsequent doses: 0.125 μg/100 g, intramuscular, 30 days) and cultured aortic vascular smooth muscle cells (VSMCs) from Sprague Dawley rats stimulated with lead (20 μg/dL) were used. Lead blood levels of treated rats attained 21.7 ± 2.38 μg/dL. Lead exposure increased systolic blood pressure and aortic ring contractile response to phenylephrine, reduced acetylcholine-induced relaxation and did not affect sodium nitroprusside relaxation. Endothelium removal and L-NAME left-shifted the response to phenylephrine more in untreated than in lead-treated rats. Apocynin and indomethacin decreased more the response to phenylephrine in treated than in untreated rats. Aortic protein expression of gp91(phox), Cu/Zn-SOD, Mn-SOD and COX-2 increased after lead exposure. In cultured VSMCs lead 1) increased superoxide anion production, NADPH oxidase activity and gene and/or protein levels of NOX-1, NOX-4, Mn-SOD, EC-SOD and COX-2 and 2) activated ERK1/2 and p38 MAPK. Both antioxidants and COX-2 inhibitors normalized superoxide anion production, NADPH oxidase activity and mRNA levels of NOX-1, NOX-4 and COX-2. Blockade of the ERK1/2 and p38 signaling pathways abolished lead-induced NOX-1, NOX-4 and COX-2 expression. Results show that lead activation of the MAPK signaling pathways activates inflammatory proteins such as NADPH oxidase and COX-2, suggesting a reciprocal interplay and contribution to vascular dysfunction as an underlying mechanisms for lead-induced hypertension. - Highlights: • Lead-exposure increases oxidative stress, COX-2 expression and vascular reactivity. • Lead exposure activates MAPK signaling pathway. • ROS and COX-2 activation by

  14. Chronic Exposure to Beta-Blockers Attenuates Inflammation and Mucin Content in a Murine Asthma Model

    Nguyen, Long P.; Omoluabi, Ozozoma; Parra, Sergio; Frieske, Joanna M.; Clement, Cecilia; Ammar-Aouchiche, Zoulikha; Ho, Samuel B.; Ehre, Camille; Kesimer, Mehmet; Knoll, Brian J.; Tuvim, Michael J; Dickey, Burton F.; Bond, Richard A.

    2007-01-01

    Single-dose administration of beta-adrenoceptor agonists produces bronchodilation and inhibits airway hyperresponsiveness (AHR), and is the standard treatment for the acute relief of asthma. However, chronic repetitive administration of beta-adrenoceptor agonists may increase AHR, airway inflammation, and risk of death. Based upon the paradigm shift that occurred with the use of beta-blockers in congestive heart failure, we previously determined that chronic administration of beta-blockers de...

  15. Chronic exposure of ecosystems and public to elements in trace contributions

    The needs in radiation protection come towards the question of chronic contaminations by trace elements or radioactive compounds. The chronicity induces to take into account a whole of redistribution mechanisms more important than the only ways of the most direct transfer. In the case of environment, that is going to become one of the way of public contamination is a target to protect, the important work is to link the contamination situation to eventual consequences on the ecosystems situation. (N.C.)

  16. Chronic exposure to perfluorinated compounds: Impact on airway hyperresponsiveness and inflammation

    Ryu, Min H.; Jha, Aruni; Ojo, Oluwaseun O.; Mahood, Thomas H.; Basu, Sujata; Detillieux, Karen A.; Nikoobakht, Neda; Wong, Charles S.; Loewen, Mark; Allan B Becker; Halayko, Andrew J.

    2014-01-01

    Emerging epidemiological evidence reveals a link between lung disease and exposure to indoor pollutants such as perfluorinated compounds (PFCs). PFC exposure during critical developmental stages may increase asthma susceptibility. Thus, in a murine model, we tested the hypothesis that early life and continued exposure to two ubiquitous household PFCs, perfluorooctanoic acid (PFOA) and perflurooctanesulfonic acid (PFOS), can induce lung dysfunction that exacerbates allergen-induced airway hype...

  17. INDUCTION OF CHRONIC KIDNEY FAILURE IN A LONG-TERM PERITONEAL EXPOSURE MODEL IN THE RAT: EFFECTS ON FUNCTIONAL AND STRUCTURAL PERITONEAL ALTERATIONS

    F. Vrtovsnik; A. Coester; D. Lopes-Barreto; D.R. de Waart; A. van der Wal; D.G. Struijk; R. Krediet; M. Zweers

    2010-01-01

    Background: A long-term peritoneal exposure model has been developed in Wistar rats. Chronic daily exposure to 3.86% glucose based, lactate buffered, conventional dialysis solutions is possible for up to 20 weeks and induces morphological abnormalities similar to those in long-term peritoneal dialys

  18. Concomitant stress potentiates the preference for, and consumption of, ethanol induced by chronic pre-exposure to ethanol

    G. Morais-Silva

    2016-01-01

    Full Text Available Ethanol abuse is linked to several acute and chronic injuries that can lead to health problems. Ethanol addiction is one of the most severe diseases linked to the abuse of this drug. Symptoms of ethanol addiction include compulsive substance intake and withdrawal syndrome. Stress exposure has an important role in addictive behavior for many drugs of abuse (including ethanol, but the consequences of stress and ethanol in the organism when these factors are concomitant results in a complex interaction. We investigated the effects of concomitant, chronic administration of ethanol and stress exposure on the withdrawal and consumption of, as well as the preference for, ethanol in mice. Male Swiss mice (30–35 g, 8-10 per group were exposed to an ethanol liquid diet as the only source of food for 15 days. In the final 5 days, they were exposed to forced swimming stress. Twelve hours after removal of the ethanol liquid diet, animals were evaluated for ethanol withdrawal by measuring anxiety-related behaviors and locomotor activity. Twenty-four hours after evaluation of ethanol withdrawal, they were evaluated for voluntary consumption of ethanol in a “three-bottle choice” paradigm. Mice exposed to chronic consumption of ethanol had decreased locomotor activity during withdrawal. Contrary to our expectations, a concomitant forced swimming stress did not aggravate ethanol withdrawal. Nevertheless, simultaneous ethanol administration and stress exposure increased voluntary consumption of ethanol, mainly solutions containing high concentrations of ethanol. These results showed that stressful situations during ethanol intake may aggravate specific addiction-related behaviors.

  19. The implications of re-analysing radiation-induced leukaemia in atomic bomb survivors: risks for acute and chronic exposures are different

    Implications of risk estimates, as required for practical radiation protection purposes, were explored through a preliminary re-analysis of leukaemia in the Japanese atomic bomb survivors using a biologically based cancer model. The calculations for the risks posed for contracting leukaemia pointed to important differences between low-dose-rate ('chronic') and high-dose-rate ('acute') exposures. For example, the risks caused by long-term ('chronic') exposures are calculated to be substantially lower than those for 'acute' exposures. In view of these model predictions the results of epidemiological studies are discussed. (author)

  20. Impact of water-accommodated fractions of crude oil on Atlantic cod, Gadus morhua following chronic exposure

    This study examined the long-term effects of hydrocarbon exposure on the gonadal development of fish. Mature Atlantic cod (Gadus morhua) were exposed to low concentrations of water accommodated fractions (WAFs) of polycyclic aromatic hydrocarbons (PAHs) in an ambient flowthrough seawater system. Some PAH-exposed cod groups were depurated afterwards for 38 to 287 days. Mortality was rare, and external lesions occurred only in the PAH-exposed groups. The gonado-somatic index revealed that gonadal development was disrupted in both sexes and spawning and spermiation was delayed in the 33 depurated PAH-groups. The findings indicate that chronic exposure to WAFs in the water column may have an adverse effect on reproduction in Atlantic cod.

  1. Effects of chronic produced water exposure on the expression of some immune-related genes of juvenile Atlantic cod

    This study assessed the impacts of exposure to processed water produced by offshore oil operators on immune-related genes of juvenile Atlantic cod exposed to processed water for a period of 22 weeks. The study investigated the influence of processed water concentrations on growth parameters; food consumption; plasma cortisol; respiratory burst activity (RB); and mRNA expression. The study showed that the RB of circulating leukocytes was significantly elevated. Significant up-regulation of the mRNA expression of microglobulin, immunoglobulin light chain, and interleukins was observed in some fish. The down-regulation of the interferon stimulated gene was also observed. The study indicated that chronic exposure to significant amounts of processed water causes modulations of the immune system of juvenile Atlantic cod.

  2. In vivo chronic intermittent ethanol exposure reverses the polarity of synaptic plasticity in the nucleus accumbens shell.

    Jeanes, Zachary M; Buske, Tavanna R; Morrisett, Richard A

    2011-01-01

    Glutamatergic synaptic plasticity in the nucleus accumbens (NAc) is implicated in response to sensitization to psychomotor-stimulating agents, yet ethanol effects here are undefined. We studied the acute in vitro and in vivo effects of ethanol in medium spiny neurons from the shell NAc subregion of slices of C57BL/6 mice by using whole-cell voltage-clamp recordings of α-amino-3-hydroxy-5-methyl-isoxazole-4-propionic acid (AMPA) excitatory postsynaptic current (EPSCs). Synaptic conditioning (low-frequency stimulation with concurrent postsynaptic depolarization) reliably depressed AMPA EPSCs by nearly 30%; this accumbal long-term depression (LTD) was blocked by a nonselective N-methyl-D-aspartate (NMDA) receptor antagonist (DL-2-amino-5-phosphonovaleric acid) and a selective NMDA receptor 2B antagonist [R-(R*,S*)-α-(4-hydroxyphenyl)-β-methyl-4-(phenylmethyl)-1-piperidine propanol]. Acute ethanol exposure inhibited the depression of AMPA EPSCs differentially with increasing concentrations, but this inhibitory action of ethanol was occluded by a D1-selective dopamine receptor agonist. Ethanol dependence was elicited in C57BL/6 mice by two separate 4-day bouts of chronic intermittent ethanol (CIE) vapor exposure. When assessed 24 h after a single bout of in vivo CIE vapor exposure, NAc LTD was absent, and instead NMDA receptor-dependent synaptic potentiation [long-term potentiation (LTP)] was reliably observed. It is noteworthy that both LTP and LTD were completely absent after an extended withdrawal (72 h) after a single 3-day CIE vapor bout. These observations demonstrate that 1) accumbal synaptic depression is mediated by NR2B receptors, 2) accumbal synaptic depression is highly sensitive to both acute and chronic ethanol exposure, and 3) alterations in this synaptic process may constitute a neural adaptation that contributes to the induction and/or expression of ethanol dependence. PMID:20947635

  3. Chronic Exposure to Androgenic-Anabolic Steroids Exacerbates Axonal Injury and Microgliosis in the CHIMERA Mouse Model of Repetitive Concussion.

    Namjoshi, Dhananjay R; Cheng, Wai Hang; Carr, Michael; Martens, Kris M; Zareyan, Shahab; Wilkinson, Anna; McInnes, Kurt A; Cripton, Peter A; Wellington, Cheryl L

    2016-01-01

    Concussion is a serious health concern. Concussion in athletes is of particular interest with respect to the relationship of concussion exposure to risk of chronic traumatic encephalopathy (CTE), a neurodegenerative condition associated with altered cognitive and psychiatric functions and profound tauopathy. However, much remains to be learned about factors other than cumulative exposure that could influence concussion pathogenesis. Approximately 20% of CTE cases report a history of substance use including androgenic-anabolic steroids (AAS). How acute, chronic, or historical AAS use may affect the vulnerability of the brain to concussion is unknown. We therefore tested whether antecedent AAS exposure in young, male C57Bl/6 mice affects acute behavioral and neuropathological responses to mild traumatic brain injury (TBI) induced with the CHIMERA (Closed Head Impact Model of Engineered Rotational Acceleration) platform. Male C57Bl/6 mice received either vehicle or a cocktail of three AAS (testosterone, nandrolone and 17α-methyltestosterone) from 8-16 weeks of age. At the end of the 7th week of treatment, mice underwent two closed-head TBI or sham procedures spaced 24 h apart using CHIMERA. Post-repetitive TBI (rTBI) behavior was assessed for 7 d followed by tissue collection. AAS treatment induced the expected physiological changes including increased body weight, testicular atrophy, aggression and downregulation of brain 5-HT1B receptor expression. rTBI induced behavioral deficits, widespread axonal injury and white matter microgliosis. While AAS treatment did not worsen post-rTBI behavioral changes, AAS-treated mice exhibited significantly exacerbated axonal injury and microgliosis, indicating that AAS exposure can alter neuronal and innate immune responses to concussive TBI. PMID:26784694

  4. Chronic xerostomia increases esophageal acid exposure and is associated with esophageal injury

    OBJECTIVES: To assess the effects of chronic xerostomia on parameters of gastroesophageal reflux and esophagitis. DESIGN: Observational study of a cohort of male patients with xerostomia and age-matched control subjects. SETTING: Tertiary-care Veterans Affairs Medical Center. SUBJECTS: Sixteen male patients with chronic xerostomia secondary to radiation for head and neck cancers or medications. Nineteen age-matched male control subjects with comparable alcohol and smoking histories. MEASUREMENTS AND MAIN RESULTS: Esophageal motility was similar in patients with xerostomia and controls. Clearance of acid from the esophagus and 24-hour intraesophageal pH were markedly abnormal in patients with xerostomia. Symptoms and signs of esophagitis were significantly more frequent in subjects with xerostomia. CONCLUSIONS: Chronic xerostomia may predispose to esophageal injury, at least in part, by decreasing the clearance of acid from the esophagus and altering 24-hour intraesophageal pH. Esophageal injury is a previously unreported complication of long-term salivary deficiency

  5. Evaluation of the effect of chronic exposure to 137Cesium on sleep-wake cycle in rats

    Since the Chernobyl accident, the most significant problem for the population living in the contaminated areas is chronic exposure by ingestion of radionuclides, notably 137Cs, a radioactive isotope of cesium. It can be found in the whole body, including the central nervous system. The present study aimed to assess the effect of 137Cs on the central nervous system and notably on open-field activity and the electroencephalographic pattern. Rats were exposed up to 90 days to drinking water contaminated with 137Cs at a dosage of 400 Bq kg-1, which is similar to that ingested by the population living in contaminated territories. At this level of exposure, no significant effect was observed on open-field activity. On the other hand, at 30 days exposure, 137Cs decreased the number of episodes of wakefulness and slow wave sleep and increased the mean duration of these stages. At 90 days exposure, the power of 0.5-4 Hz band of 137Cs-exposed rats was increased in comparison with controls. These electrophysiological changes may be due to a regional 137Cs accumulation in the brain stem. In conclusion, the neurocognitive effects of 137Cs need further evaluation and central disorders of population living in contaminated territories must be considered

  6. Evaluation of the genotoxic effects of chronic low-dose ionizing radiation exposure on nuclear medicine workers

    Introduction: Nuclear medicine workers are occupationally exposed to chronic ionizing radiation. It is known that ionizing radiation may have damaging effects on chromosomes. In the present study, we investigated the genotoxic effects of ionizing radiation on nuclear medicine workers. We used two different indicators of genotoxicity methods: sister chromatid exchange (SCE) and micronucleus (MN). Methods: The present research was carried out using 21 nuclear medicine workers (11 females and 10 males) during two periods: during normal working conditions and after a 1-month vacation. The radiation dose varied from 1.20 to 48.56 mSv, which accumulated during the occupational exposure time between two vacations. Peripheral blood samples were taken from each subject for two distinct lymphocyte cultures (SCE and MN) in each period. Results: In nearly all subjects, SCE values increased significantly during radiation exposure compared to the postvacation period (P<.05). Similarly, MN frequencies in most of the subjects increased significantly during radiation exposure compared to the postvacation period (P<.05). Conclusions: This study revealed that both SCE and MN frequencies in most of the subjects were significantly higher during exposure to ionizing radiation than after a 1-month vacation period. However, this genotoxic effect was reversible in most of the subjects.

  7. Chronic exposure to perfluorooctane sulfonate induces behavior defects and neurotoxicity through oxidative damages, in vivo and in vitro.

    Na Chen

    Full Text Available Perfluorooctane sulfonate (PFOS is an emerging persistent pollutant which shows multiple adverse health effects. However, the neurotoxicity of PFOS and its mechanisms have not been fully elucidated. Using a combination of in vivo and in vitro methods, the present study provides a detailed description of PFOS-induced neurotoxicity. Results showed that the median lethal concentration of PFOS was 2.03 mM in Caenorhabditis elegans for 48 h exposure. 20 µM PFOS caused decrease of locomotor behaviors including forward movement, body bend and head thrash. Additionally, PFOS exposure reduced chemotaxis index of C. elegans, which indicates the decline of chemotaxis learning ability. Using green fluorescent protein (GFP labelled transgenic strains, we found that PFOS caused down-regulated expression of a chemoreceptor gene, gcy-5, in ASE chemosensory neurons, but did not affect cholinergic neurons and dopaminergic neurons. In SH-SY5Y cells, 48 h exposure to 25 µM and 50 µM PFOS induced cell damage, apoptosis and the reactive oxygen species (ROS generation. PFOS caused significant increases of lipid peroxidation and superoxide dismutase activity, but an actual decrease of glutathione peroxidase activity. Furthermore, antioxidant N-acetylcysteine rescued cells from PFOS-induced apoptosis via blocking ROS. Our results demonstrate that chronic exposure to PFOS can cause obvious neurotoxicity and behavior defects. Oxidative damage and anti-oxidative deficit are crucial mechanisms in neurotoxicity of PFOS.

  8. Accidental inflation in the landscape

    We study some aspects of fine tuning in inflationary scenarios within string theory flux compactifications and, in particular, in models of accidental inflation. We investigate the possibility that the apparent fine-tuning of the low energy parameters of the theory needed to have inflation can be generically obtained by scanning the values of the fluxes over the landscape. Furthermore, we find that the existence of a landscape of eternal inflation in this model provides us with a natural theory of initial conditions for the inflationary period in our vacuum. We demonstrate how these two effects work in a small corner of the landscape associated with the complex structure of the Calabi-Yau manifold P4[1,1,1,6,9] by numerically investigating the flux vacua of a reduced moduli space. This allows us to obtain the distribution of observable parameters for inflation in this mini-landscape directly from the fluxes

  9. Effect of chronic lead exposure on kidney function in male and female rats: determination of a lead exposure biomarker.

    Ghorbe, F; Boujelbene, M; Makni-Ayadi, F; Guermazi, F; Kammoun, A; Murat, J; Croute, F; Soleilhavoup, J P; El-Feki, A

    2001-12-01

    Several cytotoxic chemical pollutants inducing peroxidative damages are liable to induce kidney failure. Among these pollutants we find heavy metals such as: lead, nickel, cadmium, vanadium and mercury. Lead is one of the most dangerous metals because it is widely spread in the environment, and because it may be a source of several nervous diseases. The aim of this study is to provide evidence concerning the effect of this metal on the renal function and to try to determine a storage corner in the organism which serves as an indicator of a lead intoxication. Lead acetate was administered by oral route in the drinking water to adult rats aged three months at the rate of 0.3% (P1) and 0.6% (P2). Reference rats received distilled water to drink under the same conditions. The treatment continued for 15, 30, 45, 60 and 90 days. The creatinemia, uremia, glycemia and creatinuria are determined by colorimetric techniques. Lead concentration in blood as well as the lead content of the tail are determined by atomic absorption after nitroperchloric mineralization at the liquid stage. The results showed an increase of creatinemia on the 30th day of the experiment for both sexes in (P1 and P2). The same happened for ureamia. The increase of these two parameters would indicate a renal deficiency which is confirmed by a decrease of creatinuria and urinary pH observed mainly on and after the 45th day of the experiment. An increase of the renal relative weight was noticed in P1 and P2 on the 30th day of the treatment. The determination of the concentration of lead in the blood shows that this factor increases among treated subjects in a constant way, independently of the dose and the duration of the treatment. Nevertheless, the rate increase of lead in the tail seems to be dose-dependent. In conclusion, lead administered by oral route causes a renal deficiency to the rat without distinction between males and females. In addition, the tail seems to be a reliable exposure biomarker

  10. Acute and chronic effects of pulse exposure of Daphnia magna to dimethoate and pirimicarb.

    Andersen, Tobias Henrik; Tjørnhøj, Rikke; Wollenberger, Leah; Slothuus, Tina; Baun, Anders

    2006-05-01

    Short-term (Daphnia magna exposed to pulses of 0.5 to 8 h in duration. During a 21-d postexposure observation period, the following parameters were monitored: Mortality, mobility, day for first offspring, animal size, weight of offspring and adults, and number of offspring produced. In general, animals exposed to a single pulse of dimethoate or pirimicarb regained mobility after 24 to 48 h in clean media. Animals exposed to repeated pulses of dimethoate did not recover mobility during a 48-h postexposure observation period, and mortality was significantly increased. Animals exposed to two pulses of pirimicarb showed less recovery of mobility compared with those exposed to one pulse. Exposure of D. magna to 30 mg/L of dimethoate or 100 microg/L of pirimicarb for 2 to 6 h resulted in a significant reduction in the number of offspring and in the average weight of offspring. The average body length was reduced after pulse exposure to 30 mg/L of dimethoate for 3 h or 70 microg/L of pirimicarb for 4 h, and these exposure concentrations caused a delay in the day for first offspring at exposure durations of 2 to 6 h. The most important new findings in the present study are that short-term (<4 h) pulse exposure of neonates to acetylcholinesterase-inhibiting pesticides caused reproductive damage in D. magna and that repeated-pulse exposure significantly increased mortality in animals that apparently had recovered after a single-pulse exposure. PMID:16704047

  11. The Association between Chronic Arsenic Exposure and Hypertension: A Meta-Analysis

    Tanvir Abir

    2012-01-01

    Full Text Available Background. There is inconclusive evidence from cross-sectional and cohort studies that arsenic exposure is a risk factor involved in the development of hypertension. Methods. A database search, using several keywords, was conducted to identify relevant studies. Separate odds ratio estimates for arsenic exposure with concentration only and arsenic exposure with duration, including biomarker, were extracted from studies that met all inclusion criteria. The extracted odds ratios (OR comparing the highest exposure categories with the lowest in each study were pooled using the random effects methods of meta-analysis. Heterogeneity of odds ratios in the included studies were analyzed using I2 statistics. Results. Eight studies were analyzed. Using the exposure as arsenic concentration in the drinking water, the OR estimate was 1.9 (95% CI: 1.2–3.0, with the I2 = 92%, while using the exposure as concentration and duration, the OR estimate was 1.4 (95% CI: 0.95–2.0 with the I2 = 80%. Meta-regression was done and the quality of exposure measurement was found to be significantly associated with the effect measure. For a one unit increase in the score from exposure assessment, the odds ratio decreased by 6%. No publication bias was evident. The only major weaknesses of this study were heterogeneity across studies and small sample size. Conclusions. The study findings provide limited evidence for a relationship between arsenic and hypertension. In summary, the relationship between arsenic exposure and hypertension is still inconclusive and needs further validation through prospective cohort studies.

  12. Assessment of risks associated to ionizing radiations: lung cancers after domestic radon exposure and thyroid cancers after accidental exposure to radioactive iodines; Evaluation des risques associes aux rayonnements ionisants: cancers du poumon apres exposition domestique au radon et cancers de la thyroide apres exposition accidentelle aux iodes radioactifs

    Catelinois, O

    2004-09-15

    The aim of this work is to develop a critical analysis of quantitative risk assessment in the field of ionizing radiation and to provide new estimates of attributable risks for particular situations of environmental exposure to ionizing radiation. This work is based on knowledge about dose-response relationships and ionizing radiation exposure of the general population. The work focuses on two different situations that both present an important interest for public health: lung cancer associated with domestic radon exposures (natural situation) and thyroid cancer associated with the Chernobyl accident fallout (accidental situation). The assessment of lung cancer risk associated with domestic radon exposure considers 10 dose-response relationships resulting from miner cohorts and case-control studies in the general population. A critical review of available data on smoking habits has been performed and allowed to consider the interactions between radon and tobacco. The exposure data come from measurements campaigns carried out since the beginning of the 1980 by the Institute for Radiation protection and Nuclear Safety and the Health General Directory in France. The French lung cancer mortality data are provided by the I.N.S.E.R.M.. Estimates of the number of attributable cancers are carried out for the whole country, stratified by 8 large regions (Z.E.A.T.) and by 96 departments for the year 1999 allowing to perform a sensibility analysis according to the geographical level of calculation. Uncertainties associated to risk coefficients and exposures have been quantified and it's impact on risk estimates is calculated. The estimated number of deaths attributable to domestic radon exposure ranges from 543 (90% uncertainty interval (U.I.): 75-1,097) to 3,108 (90% U.I.: 2,996-3,221). The corresponding risk fractions range from 2.2% (90% U.I.: 0.3%-4.4%) to 12.4% (90% U.I.: 11.9%-12.8%). The assessment of thyroid cancer risk in the most exposed area of France due to

  13. Spatial variations in estimated chronic exposure to traffic-related air pollution in working populations: A simulation

    Cloutier-Fisher Denise

    2008-07-01

    Full Text Available Abstract Background Chronic exposure to traffic-related air pollution is associated with a variety of health impacts in adults and recent studies show that exposure varies spatially, with some residents in a community more exposed than others. A spatial exposure simulation model (SESM which incorporates six microenvironments (home indoor, work indoor, other indoor, outdoor, in-vehicle to work and in-vehicle other is described and used to explore spatial variability in estimates of exposure to traffic-related nitrogen dioxide (not including indoor sources for working people. The study models spatial variability in estimated exposure aggregated at the census tracts level for 382 census tracts in the Greater Vancouver Regional District of British Columbia, Canada. Summary statistics relating to the distributions of the estimated exposures are compared visually through mapping. Observed variations are explored through analyses of model inputs. Results Two sources of spatial variability in exposure to traffic-related nitrogen dioxide were identified. Median estimates of total exposure ranged from 8 μg/m3 to 35 μg/m3 of annual average hourly NO2 for workers in different census tracts in the study area. Exposure estimates are highest where ambient pollution levels are highest. This reflects the regional gradient of pollution in the study area and the relatively high percentage of time spent at home locations. However, for workers within the same census tract, variations were observed in the partial exposure estimates associated with time spent outside the residential census tract. Simulation modeling shows that some workers may have exposures 1.3 times higher than other workers residing in the same census tract because of time spent away from the residential census tract, and that time spent in work census tracts contributes most to the differences in exposure. Exposure estimates associated with the activity of commuting by vehicle to work were

  14. Risk behaviors in a rural community with a known point-source exposure to chronic wasting disease

    Weeks Jennifer

    2008-06-01

    Full Text Available Abstract Background The emergence and continuing spread of Chronic Wasting Disease (CWD in cervids has now reached 14 U.S. states, two Canadian provinces, and South Korea, producing a potential for transmission of CWD prions to humans and other animals globally. In 2005, CWD spread for the first time from the Midwest to more densely populated regions of the East Coast. As a result, a large cohort of individuals attending a wild game feast in upstate New York were exposed to a deer that was subsequently confirmed positive for CWD. Methods Eighty-one participants who ingested or otherwise were exposed to a deer with chronic wasting disease at a local New York State sportsman's feast were recruited for this study. Participants were administered an exposure questionnaire and agreed to follow-up health evaluations longitudinally over the next six years. Results Our results indicate two types of risks for those who attended the feast, a Feast Risk and a General Risk. The larger the number of risk factors, the greater the risk to human health if CWD is transmissible to humans. Long-term surveillance of feast participants exposed to CWD is ongoing. Conclusion The risk data from this study provide a relative scale for cumulative exposure to CWD-infected tissues and surfaces, and those in the upper tiers of cumulative risk may be most at risk if CWD is transmissible to humans.

  15. Alteration of Blood Parameters and Histoarchitecture of Liver and Kidney of Silver Barb after Chronic Exposure to Quinalphos

    Golam Mohammod Mostakim

    2015-01-01

    Full Text Available Quinalphos (QP is commonly used for pest control in the agricultural fields surrounding freshwater reservoirs. This study was conducted to evaluate the chronic toxicity of this pesticide on blood parameters and some organs of silver barb, Barbonymus gonionotus. Fish were exposed to two sublethal concentrations, 0.47 ppm and 0.94 ppm, of QP for a period of 28 days. All the blood parameters (red blood cell, hematocrit, and hemoglobin and blood glucose except for white blood cells decreased with increasing concentration of toxicant and become significantly lower (p<0.05 at higher concentration when compared with control. The derived hematological indices of mean corpuscular volume, mean corpuscular hemoglobin, and mean corpuscular hemoglobin concentration were equally altered compared to control. Histoarchitectural changes of liver and kidney were observed after exposure to the QP. Hypertrophy of hepatocytes, mild to severe necrosis, ruptured central vein, and vacuolation were observed in the liver of treated groups. Highly degenerated kidney tubules and hematopoietic tissue, degeneration of renal corpuscle, vacuolization, and necrosis were evident in the kidney of treated groups. In conclusion, chronic exposure to QP at sublethal concentrations induced hematological and histological alterations in silver barb and offers a simple tool to evaluate toxicity derived alterations.

  16. A study assessing the genotoxicity in rats after chronic oral exposure to a low dose of depleted uranium

    The aim of this study was to evaluate the potential genotoxicity induced by chronic oral exposure to depleted uranium (DU). Weanling Wistar rats (F0), 50/sex/group, were exposed to DU in food at doses of 0, 4, or 40 mg kg-1 day-1 for four months. They were subsequently mated, resulting in the birth of F1 rats. Fifty F1 weanlings/sex/group were exposed for four months to the same dose levels as their parents. After four months, the uranium content in the tissues, the potential damage to the genetic material, and pathomorphological changes of the testicles were observed in both F0 and F1 rats. The genotoxicity of DU was evaluated by the following methods: sperm abnormality assessment, the bone-marrow micronucleus test, and the comet assay. Uranium content in F1 rats was significantly higher than that in F0 rats in both the kidney and ovary (p1 with F0 rats, significant differences were detected for most of the indicators, with F1 rats always exhibiting more damage (p1 rats. Genotoxicity may be induced in rats after chronic oral exposure to a low dose of DU. (author)

  17. Effect of chronic exposure to cadmium on serum lipid, lipoprotein and oxidative stress indices in male rats

    Samarghandian Saeed

    2015-09-01

    Full Text Available Cadmium (Cd is an environmental toxic metal implicated in lipid abnormalities. The present study was designed to elucidate the possible association between chronic exposure to Cd concentration and alterations in plasma lipid, lipoprotein, and oxidative stress indices in rats. Sixteen male rats were assigned to 2 groups of 8 rats each (test and control. The Cd-exposed group obtained drinking water containing cadmium chloride (CdCl2 in the concentration of 2.0 mg Cd/L in drinking water for 3 months. At the end of the experimental period, blood samples were obtained to determine the changes of serum triglycerides (TG, total cholesterol (TC, high-density lipoprotein cholesterol (HDL-C, low-density lipoprotein cholesterol (LDL-C, reduced glutathione (GSH, malondialdehyde (MDA and also serum Cd contents. The results of the present study indicated that Cd administration significantly increased the serum levels of TG, TC, LDL-C, MDA and Cd with reduction in the HDL-C and GSH levels. In conclusion, evidence is presented that chronic exposure to low Cd concentration can adversely affect the lipid and lipoprotein profile via lipid peroxidation.

  18. Altered differential hemocyte count in 3rd instar larvae of Drosophila melanogaster as a response to chronic exposure of Acephate

    Rajak Prem

    2015-06-01

    Full Text Available Acephate, an organophosphate (OP pesticide, was used to investigate the effects of its chronic exposure on hemocyte abundance in a non-target dipteran insect Drosophila melanogaster. For this purpose, six graded concentrations ranging from 1 to 6 μg/ml were selected, which are below the reported residual values (up to 14 μg/ml of the chemical. 1st instar larvae were fed with these concentrations up to the 3rd instar stage and accordingly hemolymph smears from these larvae were prepared for differential hemocyte count. Three types of cells are found in Drosophila hemolymph, namely, plasmatocytes, lamellocytes and crystal cells. Plasmatocyte count was found to decrease with successive increase in treatment concentrations. Crystal cells showed an increasing trend in their number. Though the number of lamellocytes was very low, a bimodal response was noticed. Lamellocyte number was found to increase with the initial three concentrations, followed by a dose dependent reduction in their number. As hemocytes are directly linked to the immune system of fruit flies, fluctuations in normal titer of these cells may affect insect immunity. Hemocytes share homologies in their origin and mode of action with the immune cells of higher organisms including man. Thus the present findings suggest that immune cells of humans and other organisms may be affected adversely under chronic exposure to Acephate.

  19. Chronic exposure to sublethal hexavalent chromium affects organ histopathology and serum cortisol profile of a teleost, Channa punctatus (Bloch)

    Effects of chronic exposures (one and two months) to sublethal doses of hexavalent chromium (2 and 4 mg/L potassium dichromate) on organ histopathology and serum cortisol profile were investigated and their overall impact on growth and behavior of a teleost fish, Channa punctatus was elucidated. Histopathological lesions were distinct in the vital organs gill, kidney and liver. The gill lamellae became lifted, fused, and showed oedema. Hyperplasia and hypertrophy of lamellar epithelial cells were distinct with desquamation. Hypertrophy of epithelial cells of renal tubules and reduction in tubular lumens were observed in the trunk kidney. The atrophy of the head kidney interrenal cells and decreased serum cortisol level indicated exhaustion of interrenal activity. Hepatocyte vacuolization and shrinkage, nuclear pyknosis and increase of sinusoidal spaces were observed in the liver. Abnormal behavioral patterns and reduced growth rate were also noticed in the exposed fish. The chronic hexavalent chromium exposure thus by affecting histopathology of gill, kidney (including interrenal tissue) and liver could impair the vital functions of respiration, excretion, metabolic regulation and maintenance of stress homeostasis which in the long-run may pose serious threat to fish health and affect their population.

  20. Chronic neonatal nicotine exposure increases mRNA expression of neurotrophic factors in the postnatal rat hippocampus.

    Son, Jong-Hyun; Winzer-Serhan, Ursula H

    2009-06-30

    Nicotine, the psychoactive ingredient in tobacco, can be neuroprotective but the mechanism is unknown. In the adult hippocampus, chronic nicotine can increase expression of growth factors which could contribute to nicotine's neuroprotective effects. During development, nicotine could also increase expression of neurotrophic factors. Therefore, we determined whether chronic neonatal nicotine (CNN) exposure increased mRNA expression levels of brain-derived neurotrophic factor (BDNF), nerve-growth factor (NGF), neurotrophin-3 (NT-3), fibroblast growth factor-2 (FGF-2), and insulin-like growth factor-1 (IGF-1). Nicotine (6 mg/kg/day in milk formula) or milk formula (controls) were delivered in three daily doses via oral gastric intubation to rat pups from postnatal day (P)1 to P8, and then sacrificed. Brains were processed for in situ hybridization using specific (35)S-labeled cRNA probes. At P8, CNN had a significant stimulant treatment effect on the expression of BDNF, FGF-2, NT-3 and IGF-1 [pCNN increased the number of IGF-1-expressing cells in CA1 (18.0%), CA3 (20.9%) and DG (17.7%). Thus, nicotine exposure during early postnatal development differentially up-regulated expression of neurotrophic factor mRNAs in the hippocampus, which could increase neurotrophic tone and alter developmental processes. PMID:19410565

  1. NEUROSENSORY EFFECTS OF CHRONIC HUMAN EXPOSURE TO ARSENIC ASSOCIATED WITH BODY BURDEN AND ENVIRONMENTAL MEASURES

    Exposure to arsenic in drinking water is known to produce a variety of health problems including peripheral neuropathy. Auditory, visual and somatosensory impairments have been reported in Mongolian farmers living in the Yellow River Valley where drinking water is contami...

  2. The Neurological Significance of Abnormal Natural Killer Cell Activity in Chronic Toxigenic Mold Exposures

    Ebere Anyanwu; Campbell, Andrew W.; Joseph Jones; Ehiri, John E; Akpan I. Akpan

    2003-01-01

    Toxigenic mold activities produce metabolites that are either broad-spectrum antibiotics or mycotoxins that are cytotoxic. Indoor environmental exposure to these toxigenic molds leads to adverse health conditions with the main outcome measure of frequent neuroimmunologic and behavioral consequences. One of the immune system disorders found in patients presenting with toxigenic mold exposure is an abnormal natural killer cell activity. This paper presents an overview of the neurological signif...

  3. Evidence for effects of chronic lead exposure on blood pressure in experimental animals: an overview.

    Victery, W

    1988-01-01

    Information obtained in a number of experimental studies conducted over the last 40 years on the effects of lead on blood pressure is reviewed. Differences in animal species, age at beginning of exposure, level of lead exposure, indices of lead burden, and blood pressure effects of each study are reported. In several of the high-dose experiments, hypertension was observed, but nephrotoxicity of lead may have contributed to its development. Moreover, in other high-dose experiments, no hyperten...

  4. Chronic Residential Exposure to Particulate Matter Air Pollution and Systemic Inflammatory Markers

    Hoffmann, Barbara; Moebus, Susanne; Dragano, Nico; Stang, Andreas; Möhlenkamp, Stefan; Schmermund, Axel; Memmesheimer, Michael; Bröcker-Preuss, Martina; Mann, Klaus; Erbel, Raimund; Jöckel, Karl-Heinz

    2009-01-01

    Background Long-term exposure to urban air pollution may accelerate atherogenesis, but mechanisms are still unclear. The induction of a low-grade systemic inflammatory state is a plausible mechanistic pathway. Objectives: We analyzed the association of residential long-term exposure to particulate matter (PM) and high traffic with systemic inflammatory markers. Methods We used baseline data from the German Heinz Nixdorf Recall Study, a population-based, prospective cohort study of 4,814 parti...

  5. Chronic exposure to particulate matter and risk of cardiovascular mortality: cohort study from Taiwan

    Tseng, Eva; Ho, Wen-Chao; Lin, Meng-Hung; Cheng, Tsun-Jen; Chen, Pau-Chung; Lin, Hsien-Ho

    2015-01-01

    Background Evidence on the association between long-term exposure to air pollution and cardiovascular mortality is limited in Asian populations. Methods We conducted a cohort study on the association between fine particulate matter (PM2.5) and cardiovascular mortality using 43,227 individuals in a civil servants health service in Taiwan. Each participant was assigned an exposure level of particulate matter based on their district of residence using air pollution data collected by the Taiwan E...

  6. Taurine improves the spatial learning and memory ability impaired by sub-chronic manganese exposure

    Lu, Cai-Ling; Tang, Shen; Meng, Zhi-Juan; He, Yi-Yuan; Song, Ling-Yong; Liu, Yin-Pin; Ma, Ning; Li, Xi-Yi; Guo, Song-Chao

    2014-01-01

    Background Excessive manganese exposure induced cognitive deficit. Several lines of evidence have demonstrated that taurine improves cognitive impairment induced by numerous neurotoxins. However, the role of taurine on manganese-induced damages in learning and memory is still elusive. This goal of this study was to investigate the beneficial effect of taurine on learning and memory capacity impairment by manganese exposure in an animal model. Results The escape latency in the Morris Water Maz...

  7. Chronic toxicity of arsenic, cobalt, chromium and manganese to Hyalella azteca in relation to exposure and bioaccumulation

    Norwood, W.P. [Department of Biology, University of Waterloo, Waterloo, ON N2L 3G1 (Canada) and Aquatic Ecosystems Protection Research Division, Environment Canada, P.O. Box 5050, Burlington, ON L7R 4A6 (Canada)]. E-mail: warren.norwood@ec.gc.ca; Borgmann, U. [Aquatic Ecosystems Protection Research Division, Environment Canada, P.O. Box 5050, Burlington, ON L7R 4A6 (Canada); Dixon, D.G. [Department of Biology, University of Waterloo, Waterloo, ON N2L 3G1 (Canada)

    2007-05-15

    Chronic toxicity of As, Co, Cr and Mn to Hyalella azteca can be described using a saturation-based mortality model relative to total-body or water metal concentration. LBC25s (total-body metal concentrations resulting in 25% mortality in 4 weeks) were 125, 103, 152 and 57,900 nmol g{sup -1} dry weight for As, Co, Cr and Mn respectively. LC50s (metal concentrations in water resulting in 25% mortality in 4 weeks) were 5600, 183, 731, and 197,000 nmol L{sup -1}, respectively. A hormesis growth response to As exposure was observed. Growth was a more variable endpoint than mortality for all four toxicants; however, confidence limits based on growth and mortality all overlapped, except Cr which had no effect on growth. Mn toxicity was greater in glass test containers compared to plastic. Bioaccumulation of As, Co, Cr, and Mn was strongly correlated with, and is useful for predicting, chronic mortality. - Chronic toxicity of As, Co, Cr and Mn to Hyalella azteca can be described using a saturation-based mortality model in relationship to total-body or water metal concentration.

  8. Effects of prenatal exposure to chronic mild stress and toluene in rats

    Hougaard, K. S.; Andersen, Maud Bering; Hansen, A. M.;

    2005-01-01

    female offspring of pregnant rats (Mol:WIST) exposed to chronic mild stress (CMS) during gestational days (GD) 9-20, or 1500 ppm toluene, 6 h/day during gestational days 7-20, or a combination of the two. Prenatal CMS was associated with decreased thymic weight and increased auditory startle response...

  9. Pulmonary sensitivity to ozone exposure in sedentary versus chronically trained, female rats.

    Gordon, Christopher J; Phillips, Pamela M; Beasley, Tracey E; Ledbetter, A; Aydin, Cenk; Snow, Samantha J; Kodavanti, Urmila P; Johnstone, Andrew F

    2016-06-01

    Epidemiological data suggest that a sedentary lifestyle may contribute to increased susceptibility for some environmental toxicants. We developed an animal model of active versus sedentary life style by providing female Sprague-Dawley rats with continuous access to running wheels. Sedentary rats were housed in standard cages without wheels. After training for 12 wks, rats were exposed to 0, 0.25, 0.5 or 1.0 ppm ozone [O3 for 5 h/d, 1 d/wk, for 6 wk (N = 10 per group)]. Body composition (%fat, lean and fluid) was monitored noninvasively over the course of the study. Ventilatory parameters [tidal volume, minute ventilation, frequency and enhanced pause (Penh)] were assessed using whole-body plethysmography prior to O3 and 24 h after the 5th O3 exposure. Trained rats lost ∼2% body fat after 12 wk of access to running wheels. Peak wheel activity was reduced by 40% after exposure to 1.0 ppm O3. After the 5th O3 exposure, body weight and %fat were reduced in sedentary but not trained rats. Penh was significantly elevated in sedentary but not trained rats the day after exposure to 1.0 ppm O3. However, lung lavage cell counts and biomarkers of pulmonary inflammation measured 1 day after the final exposure were inconsistently affected by training. Wheel running led to marked physiological responses along with some indication of improved pulmonary recovery from O3 exposure. However, wheel running with O3 exposure may also be a detriment for some pulmonary endpoints. Overall, a sedentary lifestyle may increase susceptibility to O3, but additional studies are needed. PMID:27160658

  10. Acidentes de trabalho com exposição a material biológico entre os profissionais de Enfermagem Accidentes de trabajo con exposición a material biológico entre profesionales de enfermería Occupational accidents with exposure to human tissue in nursing professionals

    Thiago Moura de Araújo

    2012-07-01

    conclusión de que se debe prestar más atención a la prevención de estos accidentes, así como al rigor del seguimiento tras la exposiciónocupacional.The aim of this research was to identify the types of accidents among workers involving human tissue in order to raise the profile of the victims the type of exposure, and the circumstances in which accidents occurred. This was a retrospective and descriptive study based on documents. Data collection was performed using the records of the Information System for Notifiable Diseases(SINAN in a referral hospital for infectious diseases in Ceará a total of 777 cases.The results show that 94.7 of those affected were female 57.5% were nursing assistants, 88% of cases were due to percutaneous exposure 70.1% being caused by hollow needles, 87.3% with exposure to blood, and 13.7% were related to inappropriate disposal ofperforating objects at the bench, bedside, etc.. We conclude that more attention must be given to the prevention of such accidents, as well as to strict follow-up after occupational exposure.

  11. Pyranocoumarin Tissue Distribution, Plasma Metabolome and Prostate Transcriptome Impacts of Sub-Chronic Exposure to Korean Angelica Supplement in Mice.

    Zhang, Jinhui; Li, Li; Tang, Suni; Zhang, Yong; Markiewski, Maciej; Xing, Chengguo; Jiang, Cheng; Lü, Junxuan

    2016-04-01

    Herbal products containing Korean Angelica gigas Nakai (AGN) root extract are marketed as dietary supplements for memory enhancement, pain killing, and female menopausal symptom relief. We have shown the anticancer activities of AGN supplements in mouse models. To facilitate human anticancer translational research, we characterized the tissue distribution of AGN marker pyranocoumarin compounds decursin (D) and decursinol angelate (DA) ([Formula: see text]% in AGN) and their metabolite decursinol (DOH), assessed the safety of sub-chronic AGN dietary exposure in mice, and explored its impact on plasma aqueous metabolites and the prostate transcriptome. The data show that after a gavage dose, plasma contained readily detectable DOH, but little D and DA, mirroring patterns in the liver. Extra-hepatic tissues retained greater levels of DA and D than the liver did. For sub-chronic exposures, male mice were provided ad libitum AIN93M-pellet diets with 0.5 and 1% AGN for six weeks. No adverse effects were observed on the plasma biochemistry markers of liver and kidney integrity in spite of their enlargement. Histopathological examinations of the liver, kidney and other visceral organs did not reveal tissue abnormalities. Metabolomic assessment of plasma from mice fed the 1%-AGN diet suggested metabolic shifts of key amino acids especially in the methionine-cysteine cycle, purine cycle, and glycolysis-citrate cycle. Prostate transcriptomic profiling identified gene signature changes in the metabolisms of drugs, lipids and cellular energetics, neuro-muscular features, immunity and inflammation, and tumor suppressor/oncogene balance. The safety profile was corroborated with a daily [Formula: see text] injection of AGN extract (100-300[Formula: see text]mg/kg) for four weeks, which resulted in much greater systemic pyranocoumarin exposure than the dietary route did. PMID:27080944

  12. Exposure to chronic mild stress prevents kappa opioid-mediated reinstatement of cocaine and nicotine place preference

    ReamAl-Hasani

    2013-08-01

    Full Text Available Stress increases the risk of drug abuse, causes relapse to drug seeking, and potentiates the rewarding properties of both nicotine and cocaine. Understanding the mechanisms by which stress regulates the rewarding properties of drugs of abuse provides valuable insight into potential treatments for drug abuse. Prior reports have demonstrated that stress causes dynorphin release, activating kappa-opioid receptors (KOR in monoamine circuits resulting in both potentiation and reinstatement of cocaine and nicotine conditioned place preference. Here we report that kappa-opioid dependent reinstatement of cocaine and nicotine place preference is reduced when the mice are exposed to a randomized chronic mild stress regime prior to training in a conditioned place preference-reinstatement paradigm. The chronic mild stress schedule involves seven different stressors (removal of nesting for 24hr, 5min forced swim stress at 15°C, 8hr food and water deprivation, damp bedding overnight, white noise, cage tilt and disrupted home cage lighting rotated over a three-week period. This response is KOR-selective, because chronic mild stress does not protect against cocaine or nicotine drug-primed reinstatement. This protection from reinstatement is also observed following sub-chronic social defeat stress, where each mouse is placed in an aggressor mouse home cage for a period of 20 min over five days. In contrast, a single acute stressor resulted in a potentiation of KOR-induced reinstatement, similarly to previously reported. Prior studies have shown that stress alters sensitivity to opioids and prior stress can influence the pharmacodynamics of the opioid receptor system. Together, these findings suggest that exposure to different forms of stress may cause a dysregulation of kappa opioid circuitry and that changes resulting from mild stress can have protective and adaptive effects against drug relapse.

  13. Chronic occupational exposure to hexavalent chromium causes DNA damage in electroplating workers

    Ren Xiao-Bin

    2011-04-01

    Full Text Available Abstract Background Occupational exposure to chromium compounds may result in adverse health effects. This study aims to investigate whether low-level hexavalent chromium (Cr(VI exposure can cause DNA damage in electroplating workers. Methods 157 electroplating workers and 93 control subjects with no history of occupational exposure to chromium were recruited in Hangzhou, China. Chromium levels in erythrocytes were determined by graphite furnace atomic absorption spectrophotometer. DNA damage in peripheral lymphocytes was evaluated with the alkaline comet assay by three parameters: Olive tail moment, tail length and percent of DNA in the comet tail (tail DNA%. Urinary 8-OHdG levels were measured by ELISA. Results Chromium concentration in erythrocytes was about two times higher in electroplating workers (median: 4.41 μg/L than that in control subjects (1.54 μg/L, P P P P Conclusion The findings in this study indicated that there was detectable chromium exposure in electroplating workers. Low-level occupational chromium exposure induced DNA damage.

  14. Honey Bees' Behavior Is Impaired by Chronic Exposure to the Neonicotinoid Thiacloprid in the Field.

    Tison, Léa; Hahn, Marie-Luise; Holtz, Sophie; Rößner, Alexander; Greggers, Uwe; Bischoff, Gabriela; Menzel, Randolf

    2016-07-01

    The decline of pollinators worldwide is of growing concern and has been related to the use of plant-protecting chemicals. Most studies have focused on three neonicotinoid insecticides (clothianidin, imidacloprid, and thiamethoxam) currently subject to a moratorium in the EU. Here, we focus on thiacloprid, a widely used cyano-substituted neonicotinoid thought to be less toxic to honey bees and of which use has increased in the last years. Honey bees (Apis mellifera carnica) were exposed chronically to thiacloprid in the field for several weeks at a sublethal concentration. Foraging behavior, homing success, navigation performance, and social communication were impaired, and thiacloprid residue levels increased both in the foragers and the nest mates over time. The effects observed in the field were not due to a repellent taste of the substance. For the first time, we present the necessary data for the risk evaluation of thiacloprid taken up chronically by honey bees in field conditions. PMID:27268938

  15. Estimation of doses to patients with chronic radiation sickness from external occupational exposure

    The doses to patients with chronic radiation sickness who had engaged in diagnostic radiology have been estimated according to the radiation work load, type and capacity of X-ray equipment, protection conditions, data of nationwide survey on doses to X-ray workers in China, or the data of dose monitoring in working places. Based on the activities of radium sources, time taken up in performing radium therapy, distance to radium sources and radiation work load, the doses to patients who had engaged in radium therapy have been estimated. The results of estimated average doses for 29 cases of chronic radiation sickness are given. Their average red marrow dose, trunk dose and effective dose equivalent are 1.3 Gy, 1.2 Gy and 1.6 Sv, respectively

  16. Effects from offshore oil production: chronic exposure of fish to produced water

    Holth, Tor Fredrik

    2009-07-01

    The results of this study demonstrated that environmentally relevant levels of components of produced water may affect condition factor, maturation, biochemical processes and gene expression in fish. The usefulness of bile PAH and AP metabolite measurements to evaluate exposure was demonstrated in two fish species. The development of bio marker responses was shown to depend on exposure regime as well as exposure period. Lysosomal stability (LMS) in cod kidney was related to dose, the effects were observed early (within two weeks) and remained at a stable level throughout the exposure period in fish receiving both continuous and pulsed exposure. Thus, LMS appeared to be a useful marker for effects in Atlantic cod. Formation of DNA adducts in female cod liver was also related to dose, but in contrast to LMS, more than 16 weeks was required for formation of significant levels. This parameter may therefore be underestimated following short-term exposures, such as most offshore fish caging studies (often 4-6 weeks). Although a time-dependent increase was observed, it also required a continuous exposure regime, which is not often observed in the environment. Other bio markers were demonstrated either to adapt or appeared to be insensitive to the exposures. CYP1A activity (EROD) in female cod was responsive on occasion, but a reduction of activity over time was observed. Protein levels of vitellogenin and hepatic CYP1A in zebra fish, as well as AOX in cod kidneys, were not affected in the current study. Gene transcription of several distinct cellular mechanisms was clearly affected in both species, and a predominance of differentially expressed genes in zebra fish was down regulated. This indicated that down-regulation of responsive pathways may be as important or more important than up-regulation. As both presence and absence of effects following pulsed exposure were apparent (DNA adduct formation; oocyte maturation; condition factor), the effects of exposure regime on

  17. Studies on the effects of chronic exposure to mixtures of solvents

    Triebig, G.; Bestler, W.; Baumeister, P.; Weltle, D.

    1982-10-01

    In a cross-sectional-study we examined 112 workers with long term exposures to a mixture of solvents (aliphatic and aromatic hydrocarbons, esters, halogenated hydrocarbons) to objectify possible disorders of liver and/or kidneys. Because of the results of air- and biological monitoring and their evaluation according to proposed threshold limit values, the exposure and the body burden is largely tolerable. Dependent on liverspecific parameter (y-GT, GOT, GPT, GLDH) there are slight to moderate elevations in 0 up to 67 cases (0% up to 59%). Parameters of kidney function (creatinine, urea) are always in normal range. After elimination of persons with confounding factors there are no causal connections on group basis between exposure and dysfunctions of liver and kidneys. For the individual the differentiated assessment of occupational and non-occupational hepatotoxic risks is difficult.

  18. Chronic exposure to trichloroethene causes early onset of SLE-like disease in female MRL +/+ mice

    Cai, Ping; König, Rolf; Boor, Paul J; Kondraganti, Shakuntala; Kaphalia, Bhupendra S.; Khan, M. Firoze; Ansari, G.A.S.

    2007-01-01

    Trichloroethene (TCE) exacerbates the development of autoimmune responses in autoimmune-prone MRL +/+ mice. Although TCE-mediated autoimmune responses are associated with an increase in serum immunoglobulins and autoantibodies, the underlying mechanism of autoimmunity is not known. To determine the progression of TCE-mediated immunotoxicity, female MRL +/+ mice were chronically exposed to TCE through the drinking water (0.5 mg/ml of TCE) for various periods of time. Serum concentrations of an...

  19. Within- and among-population level differences in response to chronic copper exposure in southern toads, Anaxyrus terrestris

    Environmental contaminants are implicated in the global decline of amphibian populations. Copper (Cu) is a widespread contaminant that can be toxic at concentrations just above the normal physiological range. In the present study we examined the effects of chronic Cu aqueous exposure on embryos and larvae of southern toads, Anaxyrus (Bufo) terrestris. Measurable levels of Cu were found in larvae, with tissue concentrations up to 27.5 μg Cu/g dry mass. Aqueous concentrations of Cu as low as 10 μg/L significantly reduced survival to the free-swimming stage and no larvae reached metamorphosis at concentrations above 15 μg/L. Clutches from populations with prior Cu exposure had the lowest survivorship. Among several populations there was significant variation in survivorship at different levels of Cu. More data are needed to understand the underlying causes of within- and among-population resilience to anthropogenic stressors. -- Highlights: ► Southern toad, Anaxyrus terrestris, embryos and larvae are highly sensitive to Cu. ► Significant variation in survivorship exists among clutches and populations. ► Clutches with prior Cu exposure had the lowest survivorship. ► Body burdens in larvae were up to 27.5 μg Cu/g dry mass. -- Capsule: Southern toad aquatic survival is significantly reduced at 15 μg Cu/L with variation in survivorship across clutches and populations

  20. Cancer and non-cancer brain and eye effects of chronic low-dose ionizing radiation exposure

    Picano Eugenio

    2012-04-01

    Full Text Available Abstract Background According to a fundamental law of radiobiology (“Law of Bergonié and Tribondeau”, 1906, the brain is a paradigm of a highly differentiated organ with low mitotic activity, and is thus radio-resistant. This assumption has been challenged by recent evidence discussed in the present review. Results Ionizing radiation is an established environmental cause of brain cancer. Although direct evidence is lacking in contemporary fluoroscopy due to obvious sample size limitation, limited follow-up time and lack of focused research, anecdotal reports of clusters have appeared in the literature, raising the suspicion that brain cancer may be a professional disease of interventional cardiologists. In addition, although terminally differentiated neurons have reduced or mild proliferative capacity, and are therefore not regarded as critical radiation targets, adult neurogenesis occurs in the dentate gyrus of the hippocampus and the olfactory bulb, and is important for mood, learning/memory and normal olfactory function, whose impairment is a recognized early biomarker of neurodegenerative diseases. The head doses involved in radiotherapy are high, usually above 2 Sv, whereas the low-dose range of professional exposure typically involves lifetime cumulative whole-body exposure in the low-dose range of Conclusions At this point, a systematic assessment of brain (cancer and non-cancer effects of chronic low-dose radiation exposure in interventional cardiologists and staff is needed.

  1. Recent and chronic exposure of wild ducks to lead in human-modified wetlands in Santa Fe Province, Argentina.

    Ferreyra, Hebe; Romano, Marcelo; Uhart, Marcela

    2009-07-01

    Poisoning of waterfowl due to ingestion of lead pellets is a worldwide problem in areas that are subject to hunting. No studies have assessed exposure of waterbirds to this heavy metal in Argentina, in spite of intense hunting activity, and the fact that only lead ammunition is commercially available. The objective of this study was to evaluate duck exposure to lead by examining gizzard and bone samples collected from 30 wild ducks, 16 Rosy-billed Pochard (Netta peposaca), and 14 Fulvous Whistling-Duck (Dendrocygna bicolor), provided by hunters in northern Santa Fe Province, Argentina, in July 2007. Radiographs, followed by dissection of the gizzards, showed that 31% of the Rosy-billed Pochards and 29% of the Fulvous Whistling-Ducks had ingested lead pellets (between one and four per animal). Lead in bone was found at concentrations associated with detrimental health effects. In spite of the small number of samples in this project, these results indicate high levels of lead exposure (both recent and chronic) in these species. This is the first report of a problem in Argentina that could represent a threat to the health and conservation of native aquatic species, their predators, and the wetlands they inhabit. PMID:19617495

  2. Chronic diseases and early exposure to airborne mixtures: Part III. Potential origin of pre-menopausal breast cancers.

    Argo, James

    2010-03-01

    This is the third in a series dealing with chronic diseases and early exposure to airborne mixtures from industrial releases. The purpose of this study is to increase the understanding of previously unconsidered factors in the physical environment potentially acting as risk factors for female breast cancer. Data are from the Environmental Quality Database containing lifetime residential records for about 20,000 cases, with 1 of 15 cancers and about 5000 controls. Subjects resided within 25 km of all kraft mills, sulfite mills, coke ovens, oil refineries, copper, nickel and lead/zinc smelters operating in Canada in 1967-1970, and were aged or = [DMS] and increases as [DMS] increases. The probability of an adverse effect from early, intermittent and simultaneous exposure to Dioxin and DMS, manifesting as a breast cancer after a latency period of as little as 26 years, is a function of age of first exposure, distance from the source and source type. The most susceptible age cohorts are the youngest. PMID:19337314

  3. Therapeutic and space radiation exposure of mouse brain causes impaired DNA repair response and premature senescence by chronic oxidant production.

    Suman, Shubhankar; Rodriguez, Olga C; Winters, Thomas A; Fornace, Albert J; Albanese, Chris; Datta, Kamal

    2013-08-01

    Despite recent epidemiological evidences linking radiation exposure and a number of human ailments including cancer, mechanistic understanding of how radiation inflicts long-term changes in cerebral cortex, which regulates important neuronal functions, remains obscure. The current study dissects molecular events relevant to pathology in cerebral cortex of 6 to 8 weeks old female C57BL/6J mice two and twelve months after exposure to a γ radiation dose (2 Gy) commonly employed in fractionated radiotherapy. For a comparative study, effects of 1.6 Gy heavy ion 56Fe radiation on cerebral cortex were also investigated, which has implications for space exploration. Radiation exposure was associated with increased chronic oxidative stress, oxidative DNA damage, lipid peroxidation, and apoptosis. These results when considered with decreased cortical thickness, activation of cell-cycle arrest pathway, and inhibition of DNA double strand break repair factors led us to conclude to our knowledge for the first time that radiation caused aging-like pathology in cerebral cortical cells and changes after heavy ion radiation were more pronounced than γ radiation. PMID:23928451

  4. Chronic cigarette smoke exposure adversely alters 14C-arachidonic acid metabolism in rat lungs, aortas and platelets

    Male rats were exposed to freshly generated cigarette smoke once daily, 5 times a week for 10 weeks. Inhalation of smoke was verified by elevated carboxyhemoglobin in blood sampled immediately after smoke exposure and by increased lung aryl hydrocarbon hydroxylase activity 24 hours after the last smoke exposure. Aortic rings isolated from smoke-exposed rats synthesized less prostacyclin (PGI2) from 14C-arachidonic acid than rings from sham rats. Platelets from smoke-exposed rats synthesized more thromboxane (TXA2) from 14C-arachidonic acid than platelets from room controls but not those from sham rats. Lung microsomes from smoke-exposed rats synthesized more TXA2 and had a lower PGI2/TXA2 ratio than lung microsomes from room controls and shams. It is concluded that chronic cigarette smoke exposure alters arachidonic acid metabolism in aortas, platelets and lungs in a manner resulting in decreased PGI2 and increased TXA2, thereby creating a condition favoring platelet aggregation and a variety of cardiovascular diseases

  5. Acidentes ocupacionais por exposição a material biológico entre a equipe multiprofissional do atendimento pré-hospitalar Accidentes ocupacionales por exposición a material biológico entre el equipo multiprofesional de atención pre hospitalaria Occupational accidents due to exposure to biological material in the multidisciplinary team of the emergency service

    Adriana Cristina Oliveira

    2009-09-01

    ñamiento serológico, 61,2%. Estuvieron asociados al accidente: tiempo en la institución, (Odds ratio-OR 2,84; Intervalo de confianza-IC 95% 1,22-6,62, asignado en la Unidad de Soporte Avanzado, (OR 4,18; IC 95% 1,64-10,64; interacción: tiempo en la institución y asignado en la Unidad de Soporte Básico, (OR 0,27; IC 95% 0,07-1,00. Se sugiere: la implantación de protocolos después de accidentes, con el objetivo de reducirlos; la subnotificación y el aumento del acompañamiento después del accidente.This transversal, survey-based research was carried out with a multiprofessional emergency care team in Belo Horizonte, between June and December 2006. The study aimed at estimating the incidence of occupational accidents by exposure to biological material, post-accidents conducts and demographic determinant factors. The study applied a structured questionnaire and descriptive analyses, as well as incidence calculations and logistic regression. The incidence of accidents with biological material reached 20.6%, being 40.8% by sharp materials and 49.0% by body fluids; 35.3% of the accidents took place among physicians and 24.0% among nurses. Post-accidents procedures: no medical assessment, 63.3%; under-notification, 81.6%; no conduct, 55.0%; and no serological follow-up, 61.2%. Factors associated with accidents: working time in the institution (Odds Ratio - OR, 2.84; Credible Interval - CI 95% - 1.22-6.62; working in advanced support units (OR=4.18; CI 95% - 1.64-10.64; and interaction between working time in the institution and working in Basic Support Unit (OR 0.27; CI 95% - 0.07-1.00. In order to reduce accidents, the implementation of post-accident protocols and follow-up, as well as under-notification norms, are suggested.

  6. A Case of Bowen’s Disease and Small-Cell Lung Carcinoma: Long-Term Consequences of Chronic Arsenic Exposure in Chinese Traditional Medicine

    Lee, Linda; Bebb, Gwyn

    2004-01-01

    Chronic arsenic toxicity occurs primarily through inadvertent ingestion of contaminated water and food or occupational exposure, but it can also occur through medicinal ingestion. This case features a 53-year-old lifetime nonsmoker with chronic asthma treated for 10 years in childhood with Chinese traditional medicine containing arsenic. The patient was diagnosed with Bowen’s disease and developed extensive-stage small-cell carcinoma of the lung 10 years and 47 years, respectively, after the ...

  7. Chronic Corticosterone Exposure during Adolescence Reduces Impulsive Action but Increases Impulsive Choice and Sensitivity to Yohimbine in Male Sprague-Dawley Rats

    Torregrossa, Mary M.; Xie, Maylene; Taylor, Jane R.

    2012-01-01

    Chronic stress during adolescence is associated with an increased risk for alcoholism and addictive disorders. Addiction is also associated with increased impulsivity, and stress during adolescence could alter cortical circuits responsible for response inhibition. Therefore, the present study determined the effect of chronic exposure to the stress hormone corticosterone (CORT) during adolescence on tests of impulsivity in adulthood and examined possible biochemical mechanisms. Male Sprague-Da...

  8. Chronic exposure to low doses of pharmaceuticals disturbs the hepatic expression of circadian genes in lean and obese mice

    Anthérieu, Sébastien; Le Guillou, Dounia; Coulouarn, Cédric; Begriche, Karima [INSERM, U991, Université de Rennes 1, 35000 Rennes (France); Trak-Smayra, Viviane [Pathology Department, Saint-Joseph University, Beirut (Lebanon); Martinais, Sophie [INSERM, U991, Université de Rennes 1, 35000 Rennes (France); Porceddu, Mathieu [Mitologics SAS, Hôpital Robert Debré, 48 Boulevard Sérurier, 75019 Paris (France); Robin, Marie-Anne [INSERM, U991, Université de Rennes 1, 35000 Rennes (France); Fromenty, Bernard, E-mail: bernard.fromenty@inserm.fr [INSERM, U991, Université de Rennes 1, 35000 Rennes (France)

    2014-04-01

    Drinking water can be contaminated with pharmaceuticals. However, it is uncertain whether this contamination can be harmful for the liver, especially during obesity. Hence, the goal of our study was to determine whether chronic exposure to low doses of pharmaceuticals could have deleterious effects on livers of lean and obese mice. To this end, lean and ob/ob male mice were treated for 4 months with a mixture of 11 drugs provided in drinking water at concentrations ranging from 10 to 10{sup 6} ng/l. At the end of the treatment, some liver and plasma abnormalities were observed in ob/ob mice treated with the cocktail containing 10{sup 6} ng/l of each drug. For this dosage, a gene expression analysis by microarray showed altered expression of circadian genes (e.g. Bmal1, Dbp, Cry1) in lean and obese mice. RT-qPCR analyses carried out in all groups of animals confirmed that expression of 8 different circadian genes was modified in a dose-dependent manner. For some genes, a significant modification was observed for dosages as low as 10{sup 2}–10{sup 3} ng/l. Drug mixture and obesity presented an additive effect on circadian gene expression. These data were validated in an independent study performed in female mice. Thus, our study showed that chronic exposure to trace pharmaceuticals disturbed hepatic expression of circadian genes, particularly in obese mice. Because some of the 11 drugs can be found in drinking water at such concentrations (e.g. acetaminophen, carbamazepine, ibuprofen) our data could be relevant in environmental toxicology, especially for obese individuals exposed to these contaminants. - Highlights: • The contamination of drinking water with drugs may have harmful effects on health. • Some drugs can be more hepatotoxic in the context of obesity and fatty liver. • Effects of chronic exposure of trace drugs were studied in lean and obese mouse liver. Drugs and obesity present additive effects on circadian gene expression and toxicity. • Trace

  9. Chronic exposure to low doses of pharmaceuticals disturbs the hepatic expression of circadian genes in lean and obese mice

    Drinking water can be contaminated with pharmaceuticals. However, it is uncertain whether this contamination can be harmful for the liver, especially during obesity. Hence, the goal of our study was to determine whether chronic exposure to low doses of pharmaceuticals could have deleterious effects on livers of lean and obese mice. To this end, lean and ob/ob male mice were treated for 4 months with a mixture of 11 drugs provided in drinking water at concentrations ranging from 10 to 106 ng/l. At the end of the treatment, some liver and plasma abnormalities were observed in ob/ob mice treated with the cocktail containing 106 ng/l of each drug. For this dosage, a gene expression analysis by microarray showed altered expression of circadian genes (e.g. Bmal1, Dbp, Cry1) in lean and obese mice. RT-qPCR analyses carried out in all groups of animals confirmed that expression of 8 different circadian genes was modified in a dose-dependent manner. For some genes, a significant modification was observed for dosages as low as 102–103 ng/l. Drug mixture and obesity presented an additive effect on circadian gene expression. These data were validated in an independent study performed in female mice. Thus, our study showed that chronic exposure to trace pharmaceuticals disturbed hepatic expression of circadian genes, particularly in obese mice. Because some of the 11 drugs can be found in drinking water at such concentrations (e.g. acetaminophen, carbamazepine, ibuprofen) our data could be relevant in environmental toxicology, especially for obese individuals exposed to these contaminants. - Highlights: • The contamination of drinking water with drugs may have harmful effects on health. • Some drugs can be more hepatotoxic in the context of obesity and fatty liver. • Effects of chronic exposure of trace drugs were studied in lean and obese mouse liver. Drugs and obesity present additive effects on circadian gene expression and toxicity. • Trace pharmaceuticals could

  10. Chronic aflatoxin exposure in children living in Bhaktapur, Nepal: Extension of the MAL-ED study

    Fumonisin B1 (FB1) and aflatoxin B1 (AFB1) are toxic chemicals produced by molds. The molds that produce these two toxic chemicals are commonly found in corn and their co-occurence in corn has been demonstrated in many surveys. This study was conducted because it is suspected that exposure to eith...

  11. Sub-chronic lung inflammation after airway exposures to Bacillus thuringiensis biopesticides in mice

    Barfod, Kenneth K; Poulsen, Steen Seier; Hammer, Maria;

    2010-01-01

    The aim of the present study was to assess possible health effects of airway exposures to Bacillus thuringiensis (Bt) based biopesticides in mice. Endpoints were lung inflammation evaluated by presence of inflammatory cells in bronchoalveolar lavage fluid (BALF), clearance of bacteria from the lung...

  12. Accidental Bolus of Parenteral Nutrition.

    Lodeserto, Frank; Al-Jaghbeer, Mohammed; Huang, David

    2016-08-01

    There is a paucity of data that exists regarding acute toxicity and management in the setting of parental nutrition (PN) overdose. We describe a case of a patient who received an accidental rapid bolus of PN and fat emulsion. She developed a seizure, metabolic acidosis, arrhythmias, myocardial ischemia, altered mental status, hypotension, and hypoxemia likely caused by elevated triglycerides, leading to a hyperviscosity syndrome. After failing standard therapy, she was successfully treated with a single-volume plasma exchange with resolution of symptoms. Fat emulsion or intravenous lipid emulsion and much of its safety have been recently described in its use as a rescue therapy in resuscitation from drug-related toxicity. Elevated serum triglyceride levels can result in a picture similar to a hyperviscosity syndrome. Plasma exchange is a known therapeutic modality for the management of hyperviscosity syndrome and a novel therapy in the treatment of hyperviscosity syndrome due to fat emulsion therapy. In a patient receiving PN with development of rapid deterioration of clinical status, without an obvious etiology, there should be consideration of PN overdose. A rapid assessment and treatment of severe electrolyte abnormalities should be undertaken immediately to prevent life-threatening cardiovascular and central nervous system collapse. If fat emulsion was rapidly coadministered and there are signs and symptoms of hyperviscosity syndrome, then consideration should be given to plasma exchange as an effective therapeutic treatment option. PMID:25666023

  13. Hormetic response of cholinesterase from Daphnia magna in chronic exposure to triazophos and chlorpyrifos

    Shaonan Li; Yajun Tan

    2011-01-01

    In vivo activity of cholinesterase (ChE) in Daphnia magna was measured at different time points during 21-day exposure to triazophos and chlorpyrifos ranging from 0.05 to 2.50 μg/L and 0.01 to 2.00 μg/L, respectively.For exposure to triazophos, ChE was induced up to 176.5% at 1.5 μg/L and day 10 when measured by acetylthiocholine (ATCh), whereas it was induced up to 174.2% at 0.5 μg/L and day 10 when measured by butyrylthiocholine (BTCh).For exposure to chlorpyrifos, ChE was induced up to 134.0% and 160.5% when measured by ATCh and BTCh, respectivly, with both maximal inductions detected at 0.l μg/L and day 8.Obvious induction in terms of ChE activity was also detected in daphnia removed from exposures 24 hr after their birth and kept in a recovery culture for 21 days.Results indicated that the enzyme displayed symptoms of hormesis, a characteristic featured by conversion from low-dose stimulation to high-dose inhibition.In spite of that, no promotion in terms of reproduction rate and body size was detected at any tested concentrations regardless of whether the daphnia were collected at end of the 21-day exposure or at end of a 21-day recovery culture.This suggested that induction of ChE caused by anticholinesterases had nothing to do with the prosperity of the daphnia population.

  14. Hormetic response of cholinesterase from Daphnia magna in chronic exposure to triazophos and chlorpyrifos.

    Li, Shaonan; Tan, Yajun

    2011-01-01

    In vivo activity of cholinesterase (ChE) in Daphnia magna was measured at different time points during 21-day exposure to triazophos and chlorpyrifos ranging from 0.05 to 2.50 microg/L and 0.01 to 2.00 microg/L, respectively. For exposure to triazophos, ChE was induced up to 176.5% at 1.5 microg/L and day 10 when measured by acetylthiocholine (ATCh), whereas it was induced up to 174.2% at 0.5 microg/L and day 10 when measured by butyrylthiocholine (BTCh). For exposure to chlorpyrifos, ChE was induced up to 134.0% and 160.5% when measured by ATCh and BTCh, respectively, with both maximal inductions detected at 0.1 microg/L and day 8. Obvious induction in terms of ChE activity was also detected in daphnia removed from exposures 24 hr after their birth and kept in a recovery culture for 21 days. Results indicated that the enzyme displayed symptoms of hormesis, a characteristic featured by conversion from low-dose stimulation to high-dose inhibition. In spite of that, no promotion in terms of reproduction rate and body size was detected at any tested concentrations regardless of whether the daphnia were collected at end of the 21-day exposure or at end of a 21-day recovery culture. This suggested that induction of ChE caused by anticholinesterases had nothing to do with the prosperity of the daphnia population. PMID:21790060

  15. Association between Chronic Arsenic Exposure and Nutritional Status among the Women of Child Bearing Age: A Case-Control Study in Bangladesh

    Abul H. Milton

    2010-07-01

    Full Text Available The role of nutritional factors in arsenic metabolism and toxicity is yet to be fully elucidated. A low protein diet results in decreased excretion of DMA and increased tissue retention of arsenic in experimental studies. Malnourished women carry a higher risk of adverse pregnancy outcomes. Chronic exposure to high arsenic (>50 µg/L through drinking water also increases the risk of adverse pregnancy outcomes. The synergistic effects (if any of malnutrition and chronic arsenic exposure may worsen the adverse pregnancy outcomes. This population based case control study reports the association between chronic arsenic exposure and nutritional status among the rural women in Bangladesh. 348 cases (BMI < 18.5 and 360 controls (BMI 18.5–24.99 were recruited from a baseline survey conducted among 2,341 women. An excess risk for malnutrition was observed among the participants chronically exposed to higher concentrations of arsenic in drinking water after adjusting for potential confounders such as participant’s age, religion, education, monthly household income and history of oral contraceptive pills. Women exposed to arsenic >50 µg/L were at 1.9 times (Odds Ratio = 1.9, 95% CI = 1.1–3.6 increased risk of malnutrition compared to unexposed. The findings of this study suggest that chronic arsenic exposure is likely to contribute to poor nutritional status among women of 20–45 years.

  16. Chronic stress exposure decreases the cortisol awakening response in healthy young men.

    Duan, Hongxia; Yuan, Yiran; Zhang, Liang; Qin, Shaozheng; Zhang, Kan; Buchanan, Tony W; Wu, Jianhui

    2013-11-01

    Academic examination is a major stressor for students in China. Investigation of stress-sensitive endocrine responses to major examination stress serves as a good model of naturalistic chronic psychological stress in an otherwise healthy population. The cortisol awakening response (CAR) is an endocrine marker of the hypothalamic-pituitary-adrenocortical (HPA) axis in response to stress. However, it remains unknown how chronic examination stress impacts the CAR in a young healthy population To exclude the influence of sex effects on hormone level, the CAR and psychological stress responses were assessed on two consecutive workdays in 42 male participants during their preparations for the Chinese National Postgraduate Entrance Exam (NPEE) and 21 non-exam, age-matched male comparisons. On each day, four saliva samples were collected immediately after awakening, 15 minutes, 30 minutes and 60 minutes after awakening. The waking level (S1), the increase within 30 minutes after awakening (R30), the area under the curve with respect to ground (AUCg), and the area under the curve with respect to increase (AUCi) were used to quantify the CAR. Psychological stress and anxiety were assessed by the Perceived Stress Scale and the Spielberger State-Trait Anxiety Inventory, respectively. Male participants in the exam group had greater perceived stress and anxiety scores relatibe to the non-exam group. Both R30 and AUCi in the exam group were significantly lower than the comparison group and this effect was most pronounced for participants with high levels of perceived stress in the exam group. Perceived stress and anxiety levels were negatively correlated with both R30 and AUCi. Chronic examination stress can lead to the decrease of CAR in healthy young men, possibly due to reduced HPA axis activity under long-term sustained stress. PMID:23992539

  17. Chronic cough and dyspnea in ice hockey players after an acute exposure to combustion products of a faulty ice resurfacer.

    Kahan, Erika S; Martin, Ubaldo J; Spungen, Steve; Ciccolella, David; Criner, Gerard J

    2007-01-01

    The aim of this study was to characterize pulmonary function and radiologic testing in ice hockey players after exposure to combustion products of a faulty ice resurfacer. Our patients were 16 previously healthy hockey players who developed chronic cough and dyspnea after exposure. Symptom questionnaires, pulmonary function tests (PFTs), bronchoprovocation testing, cardiopulmonary exercise testing, high-resolution computed tomography (CT) imaging, and impulse oscillometry (IOS) were all used. A normal group was used for PFTs and IOS controls. Patients had onset of cough within 72 h of exposure. Ninety-two percent complained of dyspnea, 75% chest pain, and 33% hemoptysis. Eight percent were initially hospitalized for their symptoms. Eighty-five percent were treated with systemic steroids and 39% with inhaled bronchodilators. Six months postexposure, 54% complained of cough and 46% complained of dyspnea on exertion. All patients had normal PFTs; 8.3% had a significant bronchodilator response. All had normal exercise tests (mean VO2max = 90 +/- 3% predicted) and chest CTs. With IOS, 80% had a significant bronchodilator response (decreased resistance > 12% and SD score > 1; mean change = 21.1 +/- 9.9%, mean SD score = 3.1 +/- 2.5). No correlation existed between changes in resistance or reactance and spirometric values. Patient symptoms correlated significantly with bronchodilator response on IOS resistance (R=0.61, p=0.03). More than 50% of patients exposed to the combustion products of a faulty ice resurfacer remained symptomatic six months after exposure. Despite persistence of symptoms, conventional pulmonary function tests and radiologic evaluation did not reveal airway abnormalities. IOS showed evidence of increased airway resistance and small-airway disease, which correlated with patient symptoms. PMID:17294334

  18. Chronic waterborne zinc and cadmium exposures induced different responses towards oxidative stress in the liver of zebrafish.

    Zheng, Jia-Lang; Yuan, Shuang-Shuang; Wu, Chang-Wen; Li, Wei-Ye

    2016-08-01

    Based on the same toxic level of 0.6% LC50 for 96-h and the severe situation of water pollution, we compared effects of chronic Zn (180μgL(-1)) and Cd exposures (30μgL(-1)) on growth, survival, histology, ultrastructure, and oxidative stress in the liver of zebrafish for 5 weeks. Growth performance and survival rate remained relatively constant under Zn stress, but was reduced under Cd exposure. Cd exposure also induced severe pyknotic nuclei, evident ultrastructure damage, and considerable lipid inclusions in the hepatocytes. However, these phenomena were not pronounced under Zn exposure. The negative effects caused by Cd may be explained by an increase in hepatic oxidative damage, as reflected by the enhanced levels of lipid peroxidation (LPO) and protein carbonylation (PC). The reduced activity of Cu/Zn-superoxide dismutase (Cu/Zn-SOD) and catalase (CAT) may result in the enhanced hepatic oxidative damage, though the mRNA and protein levels of both genes increased and remained unchanged respectively. On the contrary, Zn up-regulated the levels of mRNA, protein and activity of Cu/Zn-SOD, which may contribute to the decreased LPO levels. Nonetheless, the sharply up-regulated mRNA levels of CAT did not induce an increase in the protein and activity levels of CAT under Zn stress. Furthermore, transcription factor NF-E2-related factor 2 (Nrf2) expression parelleled with its target genes, suggesting that Nrf2 is required for the protracted induction of antioxidant genes. In conclusion, our data demonstrated that essential and non-essential metals induced some differences in oxidative damage in fish. The differences were not caused by the transcriptional level of related genes but depended on post-transcriptional modifications. PMID:27323295

  19. Cancer and non-cancer brain and eye effects of chronic low-dose ionizing radiation exposure

    According to a fundamental law of radiobiology (“Law of Bergonié and Tribondeau”, 1906), the brain is a paradigm of a highly differentiated organ with low mitotic activity, and is thus radio-resistant. This assumption has been challenged by recent evidence discussed in the present review. Ionizing radiation is an established environmental cause of brain cancer. Although direct evidence is lacking in contemporary fluoroscopy due to obvious sample size limitation, limited follow-up time and lack of focused research, anecdotal reports of clusters have appeared in the literature, raising the suspicion that brain cancer may be a professional disease of interventional cardiologists. In addition, although terminally differentiated neurons have reduced or mild proliferative capacity, and are therefore not regarded as critical radiation targets, adult neurogenesis occurs in the dentate gyrus of the hippocampus and the olfactory bulb, and is important for mood, learning/memory and normal olfactory function, whose impairment is a recognized early biomarker of neurodegenerative diseases. The head doses involved in radiotherapy are high, usually above 2 Sv, whereas the low-dose range of professional exposure typically involves lifetime cumulative whole-body exposure in the low-dose range of < 200 mSv, but with head exposure which may (in absence of protection) arrive at a head equivalent dose of 1 to 3 Sv after a professional lifetime (corresponding to a brain equivalent dose around 500 mSv). At this point, a systematic assessment of brain (cancer and non-cancer) effects of chronic low-dose radiation exposure in interventional cardiologists and staff is needed

  20. Evaluation and mitigation of accidental releases of radioactivity

    One result of the workshop was, that even in the case of severe accident sequences in modern nuclear power plants (other facilities were not discussed), there will be enough time to take active measures in order to lower the emissions and to diminish the consequences inside and outside of the plant. On the whole, new evidence from Harrisburg show that previously estimated accidental emissions, especially of radiologically relevant nuclides, have been rather conservative and that much lower emissions are possible, if the above measures are considered. Under accident conditions, models to predict radiation exposure must be applied under the event of a short-term release. (orig./DG)

  1. CYP2E1 epigenetic regulation in chronic, low-level toluene exposure: Relationship with oxidative stress and smoking habit

    Background: CYP2E1 is a versatile phase I drug-metabolizing enzyme responsible for the biotransformation of most volatile organic compounds, including toluene. Human toluene exposure increases CYP2E1 mRNA and modifies its activity in leucocytes; however, epigenetic implications of this interaction have not been investigated. Goal: To determine promoter methylation of CYP2E1 and other genes known to be affected by toluene exposure. Methods: We obtained venous blood from 24 tannery workers exposed to toluene (mean levels: 10.86 +/− 7 mg/m3) and 24 administrative workers (reference group, mean levels 0.21 +/− 0.02 mg/m3) all of them from the city of León, Guanajuato, México. After DNA extraction and bisulfite treatment, we performed PCR-pyrosequencing in order to measure methylation levels at promoter region of 13 genes. Results: In exposed group we found significant correlations between toluene airborne levels and CYP2E1 promoter methylation (r = − .36, p < 0.05), as well as for IL6 promoter methylation levels (r = .44, p < 0.05). Moreover, CYP2E1 promoter methylation levels where higher in toluene-exposed smokers compared to nonsmokers (p = 0.009). We also observed significant correlations for CYP2E1 promoter methylation with GSTP1 and SOD1 promoter methylation levels (r = − .37, p < 0.05 and r = − .34, p < 0.05 respectively). Conclusion: These results highlight the importance of considering CYP2E1 epigenetic modifications, as well as its interactions with other genes, as key factors for unraveling the sub cellular mechanisms of toxicity exerted by oxidative stress, which can initiate disease process in chronic, low-level toluene exposure. People co-exposed to toluene and tobacco smoke are in higher risk due to a possible CYP2E1 repression. - Highlights: • We investigated gene-specific methylation in persons chronically exposed to toluene. • In a previous study, a reduced CYP2E1 activity was observed in these participants. • CYP2E1 promoter

  2. CYP2E1 epigenetic regulation in chronic, low-level toluene exposure: Relationship with oxidative stress and smoking habit

    Jiménez-Garza, Octavio, E-mail: ojimenezgarza@ugto.mx [Health Sciences Division, University of Guanajuato Campus León, Blvd. Puente del Milenio 1001, Fracción del Predio San Carlos, C.P. 37670 León, Guanajuato (Mexico); Baccarelli, Andrea A.; Byun, Hyang-Min [Laboratory of Environmental Epigenetics, Department of Environmental Health, Harvard T.H. Chan School of Public Health, 677 Huntington Avenue, Boston, MA 02115 (United States); Márquez-Gamiño, Sergio [Health Sciences Division, University of Guanajuato Campus León, Blvd. Puente del Milenio 1001, Fracción del Predio San Carlos, C.P. 37670 León, Guanajuato (Mexico); Barrón-Vivanco, Briscia Socorro [Environmental Toxicology and Pollution Laboratory, Nayarit Autonomous University, Av. Ciudad de la Cultura s/n, “Amado Nervo”, Tepic, Nayarit C.P. 63155 (Mexico); Albores, Arnulfo [Department of Toxicology, CINVESTAV, Av. Instituto Politécnico Nacional 2508, Col. San Pedro Zacatenco, 07360 Mexico DF (Mexico)

    2015-08-01

    Background: CYP2E1 is a versatile phase I drug-metabolizing enzyme responsible for the biotransformation of most volatile organic compounds, including toluene. Human toluene exposure increases CYP2E1 mRNA and modifies its activity in leucocytes; however, epigenetic implications of this interaction have not been investigated. Goal: To determine promoter methylation of CYP2E1 and other genes known to be affected by toluene exposure. Methods: We obtained venous blood from 24 tannery workers exposed to toluene (mean levels: 10.86 +/− 7 mg/m{sup 3}) and 24 administrative workers (reference group, mean levels 0.21 +/− 0.02 mg/m{sup 3}) all of them from the city of León, Guanajuato, México. After DNA extraction and bisulfite treatment, we performed PCR-pyrosequencing in order to measure methylation levels at promoter region of 13 genes. Results: In exposed group we found significant correlations between toluene airborne levels and CYP2E1 promoter methylation (r = − .36, p < 0.05), as well as for IL6 promoter methylation levels (r = .44, p < 0.05). Moreover, CYP2E1 promoter methylation levels where higher in toluene-exposed smokers compared to nonsmokers (p = 0.009). We also observed significant correlations for CYP2E1 promoter methylation with GSTP1 and SOD1 promoter methylation levels (r = − .37, p < 0.05 and r = − .34, p < 0.05 respectively). Conclusion: These results highlight the importance of considering CYP2E1 epigenetic modifications, as well as its interactions with other genes, as key factors for unraveling the sub cellular mechanisms of toxicity exerted by oxidative stress, which can initiate disease process in chronic, low-level toluene exposure. People co-exposed to toluene and tobacco smoke are in higher risk due to a possible CYP2E1 repression. - Highlights: • We investigated gene-specific methylation in persons chronically exposed to toluene. • In a previous study, a reduced CYP2E1 activity was observed in these participants. • CYP2E1

  3. Chronic toxicity of diphenhydramine hydrochloride and erythromycin thiocyanate to Daphnia, Daphnia magna, in a continuous exposure test system

    Meinertz, J.R.; Schreier, T.M.; Bernardy, J.A.; Franz, J.L.

    2010-01-01

    Diphenhydramine hydrochloride (DH; Benadryl TM, an over-the-counter antihistamine) and erythromycin thiocyanate (ET; a commonly used macrolide antibiotic) are pharmaceutical compounds whose chronic toxicity to Daphnia magna had not been characterized. Continuous exposure to DH concentrations about 5 times greater than the maximum reported environmental concentration of 0.023 lg/L for 21 days or to ET concentrations about 40 times the maximum reported environmental concentration of 6 (mu or u)g/L for 21 days did not significantly impact D. magna survival and production. In this study the no observable effect concentration for DH was 0.12 (mu or u)g/L and for ET was 248 (mu or u)g/L.

  4. The association between chronic exposure to video game violence and affective picture processing: an ERP study.

    Bailey, Kira; West, Robert; Anderson, Craig A

    2011-06-01

    Exposure to video game violence (VGV) is known to result in desensitization to violent material and may alter the processing of positive emotion related to facial expressions. The present study was designed to address three questions: (1) Does the association between VGV and positive emotion extend to stimuli other than faces, (2) is the association between VGV and affective picture processing observed with a single presentation of the stimuli, and (3) is the association between VGV and the response to violent stimuli sensitive to the relevance of emotion for task performance? The data revealed that transient modulations of the event-related potentials (ERPs) related to attentional orienting and sustained modulations of the ERPs related to evaluative processing were sensitive to VGV exposure. PMID:21461985

  5. Chronic exposure to dietary selenomethionine increases gonadal steroidogenesis in female rainbow trout

    Wiseman, Steve, E-mail: steve.wiseman@usask.ca [Toxicology Centre, University of Saskatchewan, Saskatoon, SK, S7N 5B3 (Canada); Thomas, Jith K.; Higley, Eric; Hursky, Olesya [Toxicology Centre, University of Saskatchewan, Saskatoon, SK, S7N 5B3 (Canada); Pietrock, Michael [Toxicology Centre, University of Saskatchewan, Saskatoon, SK, S7N 5B3 (Canada); Department of Veterinary Biomedical Sciences, University of Saskatchewan, Saskatoon, SK, S7N 5B4 (Canada); Raine, Jason C. [Toxicology Centre, University of Saskatchewan, Saskatoon, SK, S7N 5B3 (Canada); Giesy, John P. [Toxicology Centre, University of Saskatchewan, Saskatoon, SK, S7N 5B3 (Canada); Department of Veterinary Biomedical Sciences, University of Saskatchewan, Saskatoon, SK, S7N 5B4 (Canada); Department of Zoology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451 (Saudi Arabia); Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong (Hong Kong); School of Biological Sciences, University of Hong Kong, Hong Kong (Hong Kong); Department of Zoology, Center for Integrative Toxicology, Michigan State University, East Lansing, MI 48824 (United States); State Key Laboratory of Pollution Control and Resource Reuse and School of the Environment, Nanjing University, Nanjing (China); Janz, David M. [Toxicology Centre, University of Saskatchewan, Saskatoon, SK, S7N 5B3 (Canada); Department of Veterinary Biomedical Sciences, University of Saskatchewan, Saskatoon, SK, S7N 5B4 (Canada); Hecker, Markus [Toxicology Centre, University of Saskatchewan, Saskatoon, SK, S7N 5B3 (Canada); School of Environment and Sustainability, University of Saskatchewan, Saskatoon, SK, S7N 5C8 (Canada)

    2011-10-15

    Selenomethionine (Se-Met) is the major dietary form of selenium (Se). Detrimental effects have been associated with exposure to elevated dietary selenium. Previous studies have demonstrated effects of Se on the endocrine system, in particular effects on cortisol and thyroid hormones. However, no information is available regarding effects of Se on sex steroid hormones. In the present study, effects of dietary exposure to an environmentally relevant concentration (4.54 mg/kg wet weight (ww)) of Se-Met for 126 days on concentrations of sex steroid hormones in blood plasma of female rainbow trout were determined. Furthermore, the molecular basis for effects of Se-Met on plasma sex steroid hormone concentrations was investigated. Concentrations of androstenedione (A), estrone (E1), and estradiol (E2) were 39.5-, 3.8-, and 12.7-fold greater in plasma of treated females than the untreated controls, respectively. Testosterone (T) was detected only in plasma of treated females. The greater E2 concentration stimulated greater transcript abundance of vitellogenin (vtg) and zona-radiata protein (zrp). Female rainbow trout exposed to Se-Met had greater transcript abundance of key steroidogenic proteins and enzymes, including peripheral benzodiazepine receptor (pbr), cytochrome P450 side-chain cleavage (P450scc), and 3{beta}-hydroxysteroid dehydrogenase (3{beta}-hsd). Exposure to Se-Met did not affect transcript abundance of luteinizing hormone (lh) or follicle stimulating hormone (fsh). Similarly, there was no change in transcript abundance of luteinizing hormone receptor (lhr) or follicle stimulating hormone receptor (fshr). Long-term exposure to dietary Se-Met has the potential to stimulate vitellogenesis in female rainbow trout by directly stimulating ovarian tissue steroidogenesis. This is the first study to report effects of Se on sex steroid hormone production in fish.

  6. Cocaine-conditioned odor cues without chronic exposure: Implications for the development of addiction vulnerability

    Lowen, Steven B.; Rohan, Michael L.; Timothy E Gillis; Thompson, Britta S.; Clara B.W. Wellons; Andersen, Susan L.

    2015-01-01

    Adolescents are highly vulnerable to addiction and are four times more likely to become addicted at first exposure than at any other age. The dopamine D1 receptor, which is typically overexpressed in the normal adolescent prefrontal cortex, is involved in drug cue responses and is associated with relapse in animal models. In human drug addicts, imaging methods have detected increased activation in response to drug cues in reward- and habit-associated brain regions. These same methods can be a...

  7. Induction of glutathione synthesis in human hepatocytes by acute and chronic arsenic exposure: Differential roles of mitogen-activated protein kinases

    Highlights: • Arsenic exposure increased intracellular levels of glutathione. • Mitogen-activated protein kinases were involved in glutathione homeostasis. • ERK contributed to glutathione synthesis during acute arsenic exposure. • Glutathione synthesis was regulated by p38 at least in part independent of NRF2 during chronic arsenic exposure. - Abstract: Glutathione (GSH) is a vital component of antioxidant defense which protects cells from toxic insults. Previously we found intracellular GSH was involved in cell resistance against arsenic-induced cytotoxicity. However, molecular mechanisms of GSH homeostasis during arsenic exposure are largely undefined. Here, we investigated roles of mitogen-activated protein kinases (MAPKs) in GSH synthesis pathway with two arsenic exposure strategies by using Chang human hepatocytes. In one strategy, acute arsenic exposure (20 μM, 24 h) was applied, as MAPK signaling is generally considered to be transient. In the other one, chronic arsenic exposure (500 nM, 20 weeks) was applied, which mimicked the general human exposure to arsenic. We found that acute arsenic exposure activated extracellular signal-regulated 1/2 kinases (ERK1/2) and c-Jun N-terminal kinase (JNK) in parallel with increased transcription and nuclear translocation of factor-erythroid 2-related factor 2 (NRF2) and enhanced expression of γ-glutamyl cysteine ligase catalytic subunit (GCLC), resulting in elevated intracellular GSH levels. Specific ERK inhibitor abolished arsenic-induced NRF2 nuclear translocation and GSH synthesis. During chronic arsenic exposure which induced a malignant cellular phenotype, continuous p38 activation and NRF2 nuclear translocation were observed with enhanced GSH synthesis. Specific p38 inhibitor attenuated arsenic-enhanced GSH synthesis without changing NRF2 nuclear translocation. Taken together, our results indicate MAPK pathways play an important role in cellular GSH homeostasis in response to arsenic. However, the

  8. Chronic exposure to paclobutrazol causes hepatic steatosis in male rockfish Sebastiscus marmoratus and the mechanism involved

    Sun Lingbin [State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen (China); Li Jinshou [Department of Biological Engineering, Ningde Normal University, Ningde City, Fujian (China); Zuo Zhenghong [State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen (China); Chen Meng [State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen (China); Wang Chonggang, E-mail: cgwang@xmu.edu.cn [State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen (China); State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen (China)

    2013-01-15

    Paclobutrazol (PBZ) is a triazole-containing fungicide which is widely used in agriculture. Acute toxicity can follow its extensive use but it is generally weaker than traditional pesticides such as organochlorine and organophosphorus. However, its adverse effects on aquatic organisms need to be investigated. This study was conducted to investigate the effect of PBZ exposure on the hepatic lipid metabolism of Sebastiscus marmoratus. After PBZ exposure for 50 days, hepatic lipid droplets were enlarged and the hepatic total lipid, triglyceride, total cholesterol and free fatty acid content had increased in a dose dependent manner compared to the control. The mRNA expression of lipid metabolism associated genes such as peroxisome proliferator-activated receptors (PPARs), androgen receptor, acetyl-CoA carboxylase 1, fatty acid synthesis, fatty acid bing protein 4, liver X receptor {alpha} (LXR{alpha}) and stearoyl-CoA desaturase were up-regulated by PBZ exposure. These results indicated that triazole-containing fungicides might affect the metabolism and health of fish via the multi-signal pathways of nuclear receptors such as PPARs and LXR.

  9. Neoplastic and life-span effects of chronic exposure to tritium. II. Rats exposed in utero

    A study was conducted to determine the effects on neoplasia incidence and life-span of exposure in utero to a major environmental radionuclide. Sprague-Dawley rats were continuously exposed to tritiated water (HTO) from conception through birth in doses of 0, 1, 10, 50, and 100 μCi HTO/ml body water. HTO administration was terminated at birth. Calculated cumulative doses during gestation were approximately 0, 6.6, 66, 330, and 660 rads of total body irradiation. Under these exposure conditions, the two highest doses resulted in sterile offspring. Animals surviving through 30 days postnatally were defined as the study population and observed until their deaths. Intrauterine exposures to doses up to 66 rads had no significant effects on either sex with respect to lifespan, overall neoplasia incidence, incidence rate, or onset of mammary fibroadenomas. Females exposed to 330 or 660 rads were sterile and had lower incidence rates of mammary fibroadenomas than did controls; at 660 rads females had a lower incidence of overall neoplasia and reduced mean lifespans. Sterile male offspring had reduced mean longevity after irradiation at 660 rads. Regardless of dose group, females had significantly higher incidences of neoplasia and longer life-spans than males

  10. Combined exposure to simulated microgravity and acute or chronic radiation reduces neuronal network integrity and cell survival

    Benotmane, Rafi

    During orbital or interplanetary space flights, astronauts are exposed to cosmic radiations and microgravity. This study aimed at assessing the effect of these combined conditions on neuronal network density, cell morphology and survival, using well-connected mouse cortical neuron cultures. To this end, neurons were exposed to acute low and high doses of low LET (X-rays) radiation or to chronic low dose-rate of high LET neutron irradiation (Californium-252), under the simulated microgravity generated by the Random Positioning Machine (RPM, Dutch space). High content image analysis of cortical neurons positive for the neuronal marker βIII-tubulin unveiled a reduced neuronal network integrity and connectivity, and an altered cell morphology after exposure to acute/chronic radiation or to simulated microgravity. Additionally, in both conditions, a defect in DNA-repair efficiency was revealed by an increased number of γH2AX-positive foci, as well as an increased number of Annexin V-positive apoptotic neurons. Of interest, when combining both simulated space conditions, we noted a synergistic effect on neuronal network density, neuronal morphology, cell survival and DNA repair. Furthermore, these observations are in agreement with preliminary gene expression data, revealing modulations in cytoskeletal and apoptosis-related genes after exposure to simulated microgravity. In conclusion, the observed in vitro changes in neuronal network integrity and cell survival induced by space simulated conditions provide us with mechanistic understanding to evaluate health risks and the development of countermeasures to prevent neurological disorders in astronauts over long-term space travels. Acknowledgements: This work is supported partly by the EU-FP7 projects CEREBRAD (n° 295552)

  11. Removal of high-fat diet after chronic exposure drives binge behavior and dopaminergic dysregulation in female mice.

    Carlin, Jesse L; McKee, Sarah E; Hill-Smith, Tiffany; Grissom, Nicola M; George, Robert; Lucki, Irwin; Reyes, Teresa M

    2016-06-21

    A significant contributor to the obesity epidemic is the overconsumption of highly palatable, energy dense foods. Chronic intake of palatable foods is associated with neuroadaptations within the mesocorticolimbic dopamine system adaptations which may lead to behavioral changes, such as overconsumption or bingeing. We examined behavioral and molecular outcomes in mice that were given chronic exposure to a high-fat diet (HFD; 12weeks), with the onset of the diet either in adolescence or adulthood. To examine whether observed effects could be reversed upon removal of the HFD, animals were also studied 4weeks after a return to chow feeding. Most notably, female mice, particularly those exposed to HFD starting in adolescence, demonstrated the emergence of binge-like behavior when given restricted access to a palatable food. Further, changes in dopamine-related gene expression and dopamine content in the prefrontal cortex were observed. Some of these HFD-driven phenotypes reversed upon removal of the diet, whereas others were initiated by removal of the diet. These findings have implications for obesity management and interventions, as both pharmacological and behavioral therapies are often combined with dietary interventions (e.g., reduction in calorie dense foods). PMID:27063418

  12. Mycotoxins and Antifungal Drug Interactions: Implications in the Treatment of Illnesses Due to Indoor Chronic Toxigenic Mold Exposures

    Ebere C. Anyanwu

    2004-01-01

    Full Text Available Chronic exposure to toxigenic molds in water-damaged buildings is an indoor environmental health problem to which escalating health and property insurance costs are raising a statewide concern in recent times. This paper reviews the structural and functional properties of mycotoxins produced by toxigenic molds and their interactive health implications with antifungal drugs. Fundamental bases of pathophysiological, neurodevelopmental, and cellular mechanisms of mycotoxic effects are evaluated. It is most likely that the interactions of mycotoxins with antifungal drugs may, at least in part, contribute to the observable persistent illnesses, antifungal drug resistance, and allergic reactions in patients exposed to chronic toxigenic molds. Safe dose level of mycotoxin in humans is not clear. Hence, the safety regulations in place at the moment remain inconclusive, precautionary, and arbitrary. Since some of the antifungal drugs are derived from molds, and since they have structural and functional groups similar to those of mycotoxins, the knowledge of their interactions are important in enhancing preventive measures.

  13. A Cross-Sectional Investigation of Chronic Exposure to Microcystin in Relationship to Childhood Liver Damage in the Three Gorges Reservoir Region, China

    Li, Yan; Chen, Ji-an; Zhao, Qing; Pu, Chaowen; QIU, ZHIQUN; Zhang, Renping; Shu, Weiqun

    2011-01-01

    Background: Microcystin-producing Microcystis bloom is a severe water problem in the world. Some reports indicate that chronic exposure to microcystin may result in liver damage in adults, but information on effects in children is limited. Objective: We investigated the relationship between microcystin exposure and liver damage in children. Methods: We measured microcystin concentrations in drinking water and aquatic food (carp and duck) from two lakes and four wells. Participants were 1,322 ...

  14. Evaluation and implementation of graded in vivo exposure for chronic low back pain in a German outpatient setting: a study protocol of a randomized controlled trial

    Riecke, Jenny; Holzapfel, Sebastian; Rief, Winfried; Glombiewski, Julia Anna

    2013-01-01

    Background The purpose of the present study is to introduce an adapted protocol of in vivo exposure for fear avoidant back pain patients and its implementation in the German health care system without multidisciplinary teams. Case studies demonstrated promising effects but three preceding randomized controlled trials (RCTs) could not support the former results. More empirical support is necessary to further substantiate the effectiveness of in vivo exposure. Methods A total of 108 chronic low...

  15. Effects of chronic exposure to sodium arsenite on hypothalamo-pituitary-testicular activities in adult rats: possible an estrogenic mode of action

    Jana Subarna; Jana Kuladip; Samanta Prabhat

    2006-01-01

    Abstract Background Inorganic arsenic is a major water pollutant and a known human carcinogen that has a suppressive influence on spermatogenesis and androgenesis in male reproductive system. However, the actual molecular events resulting in male reproductive dysfunctions from exposure to arsenic remain unclear. In this context, we evaluated the mode of action of chronic oral exposure of sodium arsenite on hypothalamo-pituitary- testicular activities in mature male albino rats. Methods The ef...

  16. An accidental poisoning with mitragynine.

    Karinen, Ritva; Fosen, Jan Toralf; Rogde, Sidsel; Vindenes, Vigdis

    2014-10-24

    An increasing number of drugs of abuse are sold word wide over the internet. Names like "legal highs", "herbal highs" etc. give the impression that these are safe products, although the risk of fatal reactions might be substantial. Leaves from the plant Mitragyna speciosa, contain active compounds like mitragynine and 7-hydroxymitragynine. It has been reported that the potency of 7-hydroxymitragynine at the μ-opioid receptor is 30 times higher than that of mitragynine and 17 times higher than that of morphine. Case reports regarding poisoning with Kratom are reported, but the toxic or lethal ranges for the concentrations of the active substances have not been established, and concentrations of 7-hydroxymitragynine have not been reported previously. We present a case report where a middle aged man was found dead at home. The deceased had a history of drug abuse and mental illness for several years. At autopsy, there were no significant pathological findings. Post-mortem analysis of peripheral blood revealed: zopiclone 0.043mg/L, citalopram 0.36mg/L and lamotrigine 5.4mg/L, i.e. concentrations regularly seen after therapeutic ingestion of these drugs. Additionally mitragynine 1.06mg/L and 7-hydroxymitragynine 0.15mg/L were detected in blood and both also in urine. The high concentrations of mitragynine and 7-hydroxymitragynine indicate that the cause of death is intoxication by these substances; and the circumstances point toward the manner of death being accidental. We recommend that both mitragynine and 7-hydroxymitragynine are analyzed for in cases with suspected Kratom intoxication. PMID:25453780

  17. Effects of combined exposure of F344 rats to radiation and chronically inhaled cigarette smoke

    Nuclear workers may be exposed to radiation in various forms, such as low-LET γ-irradiation or α-irradiation from inhaled 239PuO2 particles. These workers may then have increased risk for lung cancer compared to the general population. Of additional concern is the possibility that interactions between radiation and other carcinogens may increase the risk of cancer induction, compared to the risks from either type of agent alone. An important and common lung carcinogen is cigarette smoke. The purpose of this project is to better determine the combined effects of chronically inhaled cigarette smoke and either inhaled 239PuO2 or external, thoracic X-irradiation on the induction of lung cancer in rats. Histologic and dosimetric evaluations of rats in the CS + 239PuO2 study continue, and the study of CS + X rays is beginning

  18. Effects of combined exposure of F344 rats to radiation and chronically inhaled cigarette smoke

    Finch, G.L.; Nikula, K.J.; Barr, E.B. [and others

    1995-12-01

    Nuclear workers may be exposed to radiation in various forms, such as low-LET {gamma}-irradiation or {alpha}-irradiation from inhaled {sup 239}PuO{sub 2} particles. These workers may then have increased risk for lung cancer compared to the general population. Of additional concern is the possibility that interactions between radiation and other carcinogens may increase the risk of cancer induction, compared to the risks from either type of agent alone. An important and common lung carcinogen is cigarette smoke. The purpose of this project is to better determine the combined effects of chronically inhaled cigarette smoke and either inhaled {sup 239}PuO{sub 2} or external, thoracic X-irradiation on the induction of lung cancer in rats. Histologic and dosimetric evaluations of rats in the CS + {sup 239}PuO{sub 2} study continue, and the study of CS + X rays is beginning.

  19. Modifications of the input currents on VTA dopamine neurons following acute versus chronic cocaine exposure.

    Michaeli, Avner; Matzner, Henry; Poltyrev, Tatyana; Yaka, Rami

    2012-03-01

    Excitatory synapses on dopamine (DA) neurons in the ventral tegmental area (VTA) are modulated following exposure to various addictive drugs, including cocaine. Previously we have shown that cocaine affects GABA(A) receptor (GABA(A)R)-mediated neurotransmission in VTA DA neurons. This finding led us to reexamine the modulation of the excitatory synapse on these neurons in response to cocaine exposure, while the activity of GABA(A)R is uninterrupted. Using rat brain slices, evoked post synaptic currents (ePSC) were monitored and inhibitors of NMDA receptor (NMDAR) and AMPA receptor (AMPAR) were gradually added to inhibitors-free bath solution. Modifications in the efficacy of the excitatory synapses were evaluated by comparing AMPAR-mediated and NMDAR-mediated currents (AMPA/NMDA ratio). The lack of GABA(A)R inhibitors enabled us to examine parallel changes in the relation between GABA(A)R-mediated and NMDAR-mediated currents (GABA(A)/NMDA ratio). First, we found that AMPA/NMDA ratio measured under complete availability of GABA(A)R, is significantly higher than the ratio measured under GABA(A)R blockade. In addition, GABA(A)/NMDA ratio, but not AMPA/NMDA ratio, is augmented a few hours following in vitro acute cocaine exposure. When measured 24 h after in vivo single cocaine injection, no change in GABA(A)/NMDA ratio was observed, however, the AMPA/NMDA ratio was found to be significantly higher. Finally, a decrease in both ratios was detected in rats repeatedly injected with cocaine. Taken together, these results lead to a better understanding of the means by which cocaine modifies synaptic inputs on VTA DA neurons. The parallel changes in GABA(A)/NMDA ratio may suggest an interaction between inhibitory and excitatory neural systems. PMID:22197515

  20. Arrest in ciliated cell expansion on the bronchial lining of adult rats caused by chronic exposure to industrial noise

    Workers chronically exposed to high-intensity/low-frequency noise at textile plants show increased frequency of respiratory infections. This phenomenon prompted the herein investigation on the cytology of the bronchial epithelium of Wistar rats submitted to textile noise. Workplace noise from a cotton-mill room of a textile factory was recorded and reproduced in a sound-insulated animal room. The Wistar rats were submitted to a weekly schedule of noise treatment that was similar to that of the textile workers (8h/day, 5 days/week). Scanning electron microscopy (SEM) was used to compare the fine morphology of the inner surface of the bronchi in noise-exposed and control rats. SEM quantitative cytology revealed that exposure to noise for 5-7 months caused inhibition in the natural expansion of the area occupied by ciliated cells on the bronchial epithelium as adult rats grow older. This difference between noise-exposed and age-matched control rats was statistically significant (P0.05) and documents that the cytology of the rat bronchial epithelium is mildly altered by noise exposure. The decrease in the area of bronchial cilia may impair the mucociliar clearance of the respiratory airways and, thus, increase vulnerability to respiratory infection

  1. Ionizing radiation exposures in treatments of solid neoplasms are not associated with subsequent increased risks of chronic lymphocytic leukemia.

    Radivoyevitch, Tomas; Sachs, Rainer K; Gale, Robert Peter; Smith, Mitchell R; Hill, Brian T

    2016-04-01

    Exposure to ionizing radiation is not thought to cause chronic lymphocytic leukemia (CLL). Challenging this notion are recent data suggesting CLL incidence may be increased by radiation exposure from the atomic bombs (after many decades), uranium mining and nuclear power facility accidents. To assess the effects of therapeutic ionizing radiation for the treatment of solid neoplasms we studied CLL risks in data from the Surveillance, Epidemiology, and End Results (SEER) Program. Specifically, we compared the risks of developing CLL in persons with a 1(st) non-hematologic cancer treated with or without ionizing radiation. We controlled for early detection effects on CLL risk induced by surveillance after 1(st) cancer diagnoses by forming all-time cumulative CLL relative risks (RR). We estimate such CLL RR to be 1.20 (95% confidence interval, 1.17, 1.23) for persons whose 1(st) cancer was not treated with ionizing radiation and 1.00 (0.96, 1.05) for persons whose 1(st) cancer was treated with ionizing radiations. These results imply that diagnosis of a solid neoplasm is associated with an increased risk of developing CLL only in persons whose 1(st) cancer was not treated with radiation therapy. PMID:26922774

  2. Chronic Electromagnetic Exposure at Occupational Safety Level Does Not Affect the Metabolic Profile nor Cornea Healing after LASIK Surgery

    David Crouzier

    2014-01-01

    Full Text Available LASIK eye surgery has become a very common practice for myopic people, especially those in the military. Sometimes undertaken by people who need to keep a specific medical aptitude, this surgery could be performed in secret from the hierarchy and from the institute medical staff. However, even though the eyes have been previously described as one of the most sensitive organs to electromagnetic fields in the human body, no data exist on the potential deleterious effects of electromagnetic fields on the healing eye. The consequences of chronic long-lasting radar exposures at power density, in accordance with the occupational safety standards (9.71 GHz, 50 W/m2, were investigated on cornea healing. The metabolic and clinical statuses after experimental LASIK keratotomy were assessed on the different eye segments in a New Zealand rabbit model. The analysis methods were performed after 5 months of exposure (1 hour/day, 3 times/week. Neither clinical or histological examinations, nor experimental data, such as light scattering, 1H-NMR HRMAS metabolomics, 13C-NMR spectra of lipidic extracts, and antioxidant status, evidenced significant modifications. It was concluded that withdrawing the medical aptitude of people working in electromagnetic field environments (i.e., radar operators in the navy after eye surgery was not justified.

  3. Immuno-histomorphometric and –fluorescent characteristics of rat GH cells after chronic exposure to moderate heat

    Popovska-Perčinić Florina

    2012-01-01

    Full Text Available Growth hormone (GH axis function appears to be changed in the warm milieu. The effect of chronic exposure to moderate heat on immuno-histomorphometric and –fluorescent characteristics of pituitary GH cells, in adult male rats, was examined. The experimental group was exposed to 35±1oC for 30 days, whereas the control group was kept at room temperature during the same period. GH cells were studied using the adequate immunostaining procedures. The body weight of animals in the experimental group was significantly decreased by 24.5% compared to the controls. Immuno-histochemically and –fluorescently identified GH cells in controls were intensely stained, oval in shape, with the centrally located spherical nucleus. In rats exposed to moderate heat the localisation of GH cells was not significantly changed, while their shape was slightly different. They were mostly organized in groups, with darker cytoplasmic regions/higher intensity of immunofluorescence signal throughout the whole cytoplasm. The cellular and nuclear volumes of GH cells in the experimental group were significantly decreased by 16.0% and 9.0% respectively, but the volume density was only slightly decreased in comparison with the controls. These findings suggest that 30 days of continuous exposure of adult male rats to moderately high ambient temperature has an inhibitory effect on the immuno-histomorphometric characteristics and increases the immuno-fluorescence signal of GH cells.

  4. Effect of Chronic Exposure to Prometryne on Oxidative Stress and Antioxidant Response in Red Swamp Crayfish (Procambarus clarkii

    Alžběta Stará

    2014-01-01

    Full Text Available The aim of the study was to investigate effects of the triazine herbicide prometryne on red swamp crayfish on the basis of oxidative stress, antioxidant indices in hepatopancreas and muscle, and histopathology of hepatopancreas. Crayfish were exposed to prometryne concentrations of 0.51 μg L−1, 0.144 mg L−1, and 1.144 mg L−1 for 11 and 25 days. Indices of oxidative stress (thiobarbituric acid reactive substances (TBARS, and antioxidant parameters (superoxide dismutase (SOD, catalase (CAT, and glutathione reductase (GR in crayfish muscle and hepatopancreas were measured. Chronic exposure to prometryne did not showed the impact of oxidative damage to cells. Changes activity of the antioxidant enzymes SOD, CAT, and GR were observed in all tested concentrations to prometryne for 11 and 25 days (P<0.01 as compared with the control group. We did not see any differences in histopatological examination to hepatopancreas. Prolonged exposure of prometryne did not result in oxidative damage to cell lipids and proteins, but it led to changes in antioxidant activity in crayfish tissues. Changes in antioxidant systems were also observed in the environmental prometryne concentration of 0.51 μg L−1. The results suggest that antioxidant responses may have potential as biomarkers for monitoring residual triazine herbicides in aquatic environments.

  5. Exposure of chronic obstructive pulmonary disease patients to particulate matter: relationships between personal and ambient air concentrations.

    Ebelt, S T; Petkau, A J; Vedal, S; Fisher, T V; Brauer, M

    2000-07-01

    Mot time-series studies of particulate air pollution and acute health outcomes assess exposure of the study population using fixed-site outdoor measurements. To address the issue of exposure misclassification, we evaluate the relationship between ambient particle concentrations and personal exposures of a population expected to be at risk of particle health effects. Sampling was conducted within the Vancouver metropolitan area during April-September 1998. Sixteen subjects (non-smoking, ages 54-86) with physician-diagnosed chronic obstructive pulmonary disease (COPD) wore personal PM2.5 monitors for seven 24-hr periods, randomly spaced approximately 1.5 weeks apart. Time-activity logs and dwelling characteristics data were also obtained for each subject. Daily 24-hr ambient PM10 and PM2.5 concentrations were measured at five fixed sites spaced throughout the study region. SO4(2-), which is found almost exclusively in the fine particle fraction and which does not have major indoor sources, was measured in all PM2.5 samples as an indicator of accumulation mode particulate matter of ambient origin. The mean personal and ambient PM2.5 concentrations were 18 micrograms/m3 and 11 micrograms/m3, respectively. In analyses relating personal and ambient measurements, ambient concentrations were expressed either as an average of the values obtained from five ambient monitoring sites for each day of personal sampling, or as the concentration obtained at the ambient site closest to each subject's home. The mean personal to ambient concentration ratio of all samples was 1.75 (range = 0.24 to 10.60) for PM2.5, and 0.75 (range = 0.09 to 1.42) for SO4(2-). Regression analyses were conducted for each subject separately and on pooled data. The median correlation (Pearson's r) between personal and average ambient PM2.5 concentrations was 0.48 (range = -0.68 to 0.83). Using SO4(2-) as the exposure metric, the median r between personal and average ambient concentrations was 0.96 (range

  6. Environmental behaviour of accidentally released radionuclides in urban environments

    After a nuclear accident several radionuclides may be released and may contribute to the exposure of members of the public. After the passage of the radioactive cloud, doses to members of the public are mainly due to deposited radionuclides on the ground and other environmental surfaces. For the long-term it is already known that exposure is dominated by Cs-137, although Sr isotopes may also have a significant contribution is some specific environments, related to internal exposure pathways. However, in the first year, Ru and I isotopes may significantly contribute to the exposure of members of the public, from both external and internal exposure pathways. The objective of this work was to gather data on the environmental behaviour of Sr, I and Ru isotopes on urban environments and its contributions to the population exposure, aiming the support for decision making processes on countermeasures to protect people after an accidental release. Results on relative relevance of radionuclides and pathways for the exposure for members of the public, as a function of age and time after the release, are discussed. (author)

  7. [Criteria for the determination of chronic exposure to hazardous substances via soil ingestion].

    Konietzka, R; Dieter, H H

    1994-01-01

    Legally recoverable protection of human health against pollutant effects must have for the enforcement in practice a technically comprehensible toxicological basis, i.e., a coherence or connection between the toxicological and legal definition of a dangerous situation must be found. For this purpose toxicological and socially accepted reference points in the unit "mg of pollutant amount absorbed per kg of weight per day" (mg/[kg of weight x d]) may be used to assess a danger in the sense a sufficient probability a damage to human health exists after exposure to certain pollutant concentrations. Based on the plausible toxicological assumption that above this reference point in case of an undisturbed course of action and by giving consideration to all exposure pathways a threshold of harmlessness including all groups of the population would be exceeded, criteria both for non-carcinogenic and carcinogenic substances or for substances suspected to cause cancer are being developed. These criteria allow to determine from which point the existence of a danger would be assessable as "sufficiently probable", and hence the required coherence between legal and toxicological view to be established. PMID:8148583

  8. Chronic exposure to paclitaxel diminishes phosphoinositide signaling by calpain-mediated neuronal calcium sensor-1 degradation.

    Boehmerle, Wolfgang; Zhang, Kun; Sivula, Michael; Heidrich, Felix M; Lee, Yashang; Jordt, Sven-Eric; Ehrlich, Barbara E

    2007-06-26

    Paclitaxel (Taxol) is a well established chemotherapeutic agent for the treatment of solid tumors, but it is limited in its usefulness by the frequent induction of peripheral neuropathy. We found that prolonged exposure of a neuroblastoma cell line and primary rat dorsal root ganglia with therapeutic concentrations of Taxol leads to a reduction in inositol trisphosphate (InsP(3))-mediated Ca(2+) signaling. We also observed a Taxol-specific reduction in neuronal calcium sensor 1 (NCS-1) protein levels, a known modulator of InsP(3) receptor (InsP(3)R) activity. This reduction was also found in peripheral neuronal tissue from Taxol treated animals. We further observed that short hairpin RNA-mediated NCS-1 knockdown had a similar effect on phosphoinositide-mediated Ca(2+) signaling. When NCS-1 protein levels recovered, so did InsP(3)-mediated Ca(2+) signaling. Inhibition of the Ca(2+)-activated protease mu-calpain prevented alterations in phosphoinositide-mediated Ca(2+) signaling and NCS-1 protein levels. We also found that NCS-1 is readily degraded by mu-calpain in vitro and that mu-calpain activity is increased in Taxol but not vehicle-treated cells. From these results, we conclude that prolonged exposure to Taxol activates mu-calpain, which leads to the degradation of NCS-1, which, in turn, attenuates InsP(3)mediated Ca(2+) signaling. These findings provide a previously undescribed approach to understanding and treating Taxol-induced peripheral neuropathy. PMID:17581879

  9. Life-cycle chronic gamma exposure of Arabidopsis thaliana induces growth effects but no discernable effects on oxidative stress pathways.

    Vandenhove, Hildegarde; Vanhoudt, Nathalie; Cuypers, Ann; van Hees, May; Wannijn, Jean; Horemans, Nele

    2010-09-01

    Arabidopsis thaliana was exposed to low-dose chronic gamma irradiation during a full life cycle (seed to seed) and several biological responses were investigated. Applied dose rates were 2336, 367 and 81 microGy h(-1). Following 24 days (inflorescence emergence), 34 days (approximately 50% of flowers open) and 54 days (silice ripening) exposure, plants were harvested and monitored for biometric parameters, capacities of enzymes involved in the antioxidative defence mechanisms (SOD, APOD, GLUR, GPOD, SPOD, CAT, ME), glutathione and ascorbate pool, lipid peroxidation products, altered gene expression of selected genes encoding for antioxidative enzymes or reactive oxygen species production, and DNA integrity. Root fresh weight was significantly reduced after gamma exposure compared to the control at all stages monitored but no significant differences in root weight for the different dose rates applied was observed. Leaf and stem fresh weight were significantly reduced at the highest irradiation level after 54 days exposure only. Also total plant fresh was significantly lower at silice riping and this for the highest and medium dose rate applied. The dose rate estimated to result in a 10% reduction in growth (EDR-10) ranged between 60 and 80 microGy h(-1). Germination of seeds from the gamma irradiated plants was not hampered. For several of the antioxidative defence enzymes studied, the enzyme capacity was generally stimulated towards flowering but generally no significant effect of dose rate on enzyme capacity was observed. Gene analysis revealed a significant transient and dose dependent change in expression of RBOHC indicating active reactive oxygen production induced by gamma irradiation. No effect of irradiation was observed on concentration or reduction state of the non-enzymatic antioxidants, ascorbate and glutathione. The level of lipid peroxidation products remained constant throughout the observation period and was not affected by dose rate. The comet assay

  10. Chronic exposure to volcanic air pollution and DNA damage in Furnas Volcano (São Miguel Island, Azores, Portugal) inhabitants

    Linhares, Diana; Garcia, Patricia; Silva, Catarina; Ferreira, Teresa; Barroso, Joana; Camarinho, Ricardo; Rodrigues, Armindo

    2015-04-01

    Many studies in volcanic air pollution only have in consideration the acute toxic effects of gas or ash releases however the impact of chronic exposure to ground gas emissions in human health is yet poorly known. In the Azores archipelago (Portugal), São Miguel island has one of the most active and dangerous volcanoes: Furnas Volcano. Highly active fumarolic fields, hot springs and soil diffuse degassing phenomena are the main secondary volcanic phenomena that can be seen at the volcano surroundings. One of the main gases released in these diffuse degassing areas is radon (222Rn), which decay results in solid particles that readily settle within the airways. These decay particles emit alpha radiation that is capable of causing severe DNA damage that cumulatively can eventually cause cancer. Previous studies have established that chronic exposure to chromosome-damaging agents can lead to the formation of nuclear anomalies, such as micronuclei that is used for monitoring DNA damage in human populations. The present study was designed to evaluate whether chronic exposure to volcanic air pollution, associated to 222Rn, might result in DNA damage in human oral epithelial cells. A cross sectional study was performed in a study group of 142 individuals inhabiting an area where volcanic activity is marked by active fumarolic fields and soil degassing (hydrothermal area), and a reference group of 368 individuals inhabiting an area without these secondary manifestations of volcanism (non-hydrothermal area). For each individual, 1000 buccal epithelial cells were analyzed for the frequency of micronucleated cells (MNc) and the frequency of cells with other nuclear anomalies (ONA: pyknosis, karyolysis and karyorrhexis), by using the micronucleus assay. Information on lifestyle factors and an informed consent were obtained from each participant. Assessment of indoor radon was performed with the use of radon detectors. Data were analyzed with logistic regression models, adjusted

  11. Chronic exposure to low concentration of arsenic is immunotoxic to fish: Role of head kidney macrophages as biomarkers of arsenic toxicity to Clarias batrachus

    Datta, Soma; Ghosh, Debabrata [Immunobiology Laboratory, School of Life Sciences, Visva Bharati University, Santiniketan 731 235 (India); Saha, Dhira Rani [Microscopy Laboratory, National Institute of Cholera and Enteric Diseases, P-33, Scheme XM, C.I.T. Road, Beliaghata, Kolkata 700 010 (India); Bhattacharaya, Shelley [Environmental Toxicology Laboratory, School of Life Sciences, Visva Bharati University, Santiniketan 731 235 (India); Mazumder, Shibnath [Immunobiology Laboratory, School of Life Sciences, Visva Bharati University, Santiniketan 731 235 (India)], E-mail: shibnath1@yahoo.co.in

    2009-04-09

    The present study was aimed at elucidating the effect of chronic low-level arsenic exposure on the head kidney (HK) of Clarias batrachus and at determining the changes in head kidney macrophage (HKM) activity in response to arsenic exposure. Chronic exposure (30 days) to arsenic (As{sub 2}O{sub 3}, 0.50 {mu}M) led to significant increase in arsenic content in the HK accompanied by reduction in both HKM number and head kidney somatic index (HKSI). Arsenic induced HK hypertrophy, reduction in melano-macrophage population and increased hemosiderin accumulation. Transmission electron microscopy of 30 days exposed HKM revealed prominent endoplasmic reticulum, chromatin condensation and loss in structural integrity of nuclear membrane. Head kidney macrophages from exposed fish demonstrated significant levels of superoxide anions but on infection with Aeromonas hydrophila were unable to clear the intracellular bacteria and died. Exposure-challenge experiments with A. hydrophila revealed that chronic exposure to micromolar concentration of arsenic interfered with the phagocytic potential of HKM, helped in intracellular survival of the ingested bacteria inside the HKM inducing significant HKM cytotoxicity. The immunosuppressive effect of arsenic was further evident from the ability of A. hydrophila to colonize and disseminate efficiently in exposed fish. Enzyme linked immunosorbent assay indicated that chronic exposure to arsenic suppressed the production of pro-inflammatory 'IL-1{beta} like' factors from HKM. It is concluded that arsenic even at very low concentration is immunotoxic to fish and the changes observed in HKM may provide a useful early biomarker of low-level xenobiotic exposure.

  12. Chronic exposure to low concentration of arsenic is immunotoxic to fish: Role of head kidney macrophages as biomarkers of arsenic toxicity to Clarias batrachus

    The present study was aimed at elucidating the effect of chronic low-level arsenic exposure on the head kidney (HK) of Clarias batrachus and at determining the changes in head kidney macrophage (HKM) activity in response to arsenic exposure. Chronic exposure (30 days) to arsenic (As2O3, 0.50 μM) led to significant increase in arsenic content in the HK accompanied by reduction in both HKM number and head kidney somatic index (HKSI). Arsenic induced HK hypertrophy, reduction in melano-macrophage population and increased hemosiderin accumulation. Transmission electron microscopy of 30 days exposed HKM revealed prominent endoplasmic reticulum, chromatin condensation and loss in structural integrity of nuclear membrane. Head kidney macrophages from exposed fish demonstrated significant levels of superoxide anions but on infection with Aeromonas hydrophila were unable to clear the intracellular bacteria and died. Exposure-challenge experiments with A. hydrophila revealed that chronic exposure to micromolar concentration of arsenic interfered with the phagocytic potential of HKM, helped in intracellular survival of the ingested bacteria inside the HKM inducing significant HKM cytotoxicity. The immunosuppressive effect of arsenic was further evident from the ability of A. hydrophila to colonize and disseminate efficiently in exposed fish. Enzyme linked immunosorbent assay indicated that chronic exposure to arsenic suppressed the production of pro-inflammatory 'IL-1β like' factors from HKM. It is concluded that arsenic even at very low concentration is immunotoxic to fish and the changes observed in HKM may provide a useful early biomarker of low-level xenobiotic exposure

  13. Differences in Depression, Posttraumatic Stress Disorder, and Lifetime Trauma Exposure in Formerly Abused Women with Mild versus Moderate to Severe Chronic Pain

    Humphreys, Janice; Cooper, Bruce A.; Miaskowski, Christine

    2010-01-01

    Although associations between intimate partner violence, chronic pain, depression, posttraumatic stress disorder (PTSD), and lifetime trauma exposure are well known, previous studies are limited by their recruitment of women from shelters. These relationships were explored with a community-based sample of formerly abused women ( N = 84).…

  14. Mortalidad intrahospitalaria por accidente cerebrovascular

    Federico Rodríguez Lucci

    2013-08-01

    Full Text Available La mortalidad global por accidente cerebrovascular (ACV ha disminuido en las últimas tres décadas, probablemente debido a un mejor control de los factores de riesgo vascular. La mortalidad hospitalaria por ACV ha sido tradicionalmente estimada entre 6 y 14% en la mayoría de las series comunicadas. Sin embargo, los datos de ensayos clínicos recientes sugieren que esta cifra sería sustancialmente menor. Se revisaron datos de pacientes internados con diagnóstico de ACV del Banco de Datos de Stroke de FLENI y los registros institucionales de mortalidad entre los años 2000 y 2010. Los subtipos de ACV isquémicos se clasificaron según criterios TOAST y los ACV hemorrágicos en hematomas intrapanquimatosos, hemorragias subaracnoideas aneurismáticas, malformaciones arteriovenosas y otros hematomas intraparenquimatosos. Se analizaron 1514 pacientes, 1079 (71% con ACV isquémico (grandes vasos 39%, cardioembólicos 27%, lacunares 9%, etiología indeterminada 14%, otras etiologías 11% y 435 (29% con ACV hemorrágico (intraparenquimatosos 27%, hemorragia subaracnoidea 30%, malformaciones arteriovenosas 25% y otros hematomas espontáneos 18%. Se registraron 38 muertes intrahospitalarias (17 ACV isquémicos y 21 ACV hemorrágicos, representando una mortalidad global del 2.5% (1.7% en ACV isquémicos y 4.8% en ACV hemorrágicos. No se registraron muertes asociadas al uso de fibrinolíticos endovenosos. La mortalidad intrahospitalaria en pacientes con ACV isquémico y hemorrágico en nuestro centro fue baja. El manejo en un centro dedicado a las enfermedades neurológicas y el enfoque multidisciplinario por personal médico y no médico entrenado en el cuidado de la enfermedad cerebrovascular podrían explicar, al menos en parte, estos resultados.

  15. Estudo sobre os acidentes de trabalho com exposição aos líquidos corporais humanos em trabalhadores da saúde de um hospital universitário Estudio sobre los accidentes de trabajo con exposicíon a líquidos corporales humanos en trabajadores de la salud de un hospital universitario Study of work accidents related to human body fluids exposure among health workers at a university hospital

    Ana Cristina Balsamo

    2006-06-01

    trabajadores declaró que el accidente "simplemente aconteció" y el 29,17% no tenía sugerencias. Este estudio aportó herramientas importantes para la revisión y elaboración de estrategias de prevención de los accidentes con exposición a los líquidos corporales humanos.This descriptive and exploratory study from a quantitative approach aimed to characterize workers who were victims of work accidents related to human body fluids exposure and to evaluate the accident victim care protocol. The population consisted of 48 workers who were victims of work accidents involving exposure to human body fluids, from July 2000 to June 2001. Data were collected through a form and interviews. Results showed that nursing workers presented higher accident risk levels and that 87.50% involved piercing and cutting material, such as needles and butterflies (70%. As to the accident-related situation/activity, the workers indicated that 25% were due to an "inadequate act during the procedure"; 19.64% mentioned that "it happened" and 29.17% answered that they did not have any suggestion. This study provided important tools to review and elaborate strategies to prevent accidents involving exposure to human body fluids.

  16. The effect of chronic chromium exposure on the health of Chinook salmon (Oncorhynchus tshawytscha)

    Farag, Aida M. [United States Geological Survey, Columbia Environmental Research Center, Jackson Field Research Station, P.O. Box 1089, Jackson, WY 83001 (United States)]. E-mail: aida_farag@usgs.gov; May, Thomas [United States Geological Survey, Columbia Environmental Research Center, Columbia, MO 65201 (United States); Marty, Gary D. [Department of Anatomy, Physiology, and Cell Biology, School of Veterinary Medicine, University of California, 1 Shields Ave., Davis, CA 95616-8732 (United States); Easton, Michael [International EcoGen Inc., 2015 McLallen Court, North Vancouver, BC, Canada V7P 3H6 (Canada); Harper, David D. [United States Geological Survey, Columbia Environmental Research Center, Jackson Field Research Station, P.O. Box 1089, Jackson, WY 83001 (United States); Little, Edward E. [United States Geological Survey, Columbia Environmental Research Center, Columbia, MO 65201 (United States); Cleveland, Laverne [United States Geological Survey, Columbia Environmental Research Center, Columbia, MO 65201 (United States)

    2006-03-10

    This study was designed to determine fish health impairment of Chinook salmon (Oncorhynchus tshawytscha) exposed to chromium. Juvenile Chinook salmon were exposed to aqueous chromium concentrations (0-266 {mu}g l{sup -1}) that have been documented in porewater from bottom sediments and in well waters near salmon spawning areas in the Columbia River in the northwestern United States. After Chinook salmon parr were exposed to 24 and 54 {mu}g Cr l{sup -1} for 105 days, neither growth nor survival of parr was affected. On day 105, concentrations were increased from 24 to 120 {mu}g Cr l{sup -1} and from 54 to 266 {mu}g Cr l{sup -1} until the end of the experiment on day 134. Weight of parr was decreased in the 24/120 {mu}g Cr l{sup -1} treatment, and survival was decreased in the 54/266 {mu}g Cr l{sup -1} treatment. Fish health was significantly impaired in both the 24/120 and 54/266 {mu}g Cr l{sup -1} treatments. The kidney is the target organ during chromium exposures through the water column. The kidneys of fish exposed to the greatest concentrations of chromium had gross and microscopic lesions (e.g. necrosis of cells lining kidney tububules) and products of lipid peroxidation were elevated. These changes were associated with elevated concentrations of chromium in the kidney, and reduced growth and survival. Also, variations in DNA in the blood were associated with pathological changes in the kidney and spleen. These changes suggest that chromium accumulates and enters the lipid peroxidation pathway where fatty acid damage and DNA damage (expressed as chromosome changes) occur to cause cell death and tissue damage. While most of the physiological malfunctions occurred following parr exposures to concentrations {>=}120 {mu}g Cr l{sup -1}, nuclear DNA damage followed exposures to 24 {mu}g Cr l{sup -1}, which was the smallest concentration tested. The abnormalities measured during this study are particularly important because they are associated with impaired growth

  17. Chronic effects of temperature on mortality in the Southeastern USA using satellite-based exposure metrics

    Shi, Liuhua; Liu, Pengfei; Wang, Yan; Zanobetti, Antonella; Kosheleva, Anna; Koutrakis, Petros; Schwartz, Joel

    2016-07-01

    Climate change may affect human health, particularly for elderly individuals who are vulnerable to temperature changes. While many studies have investigated the acute effects of heat, only a few have dealt with the chronic ones. We have examined the effects of seasonal temperatures on survival of the elderly in the Southeastern USA, where a large fraction of subpopulation resides. We found that both seasonal mean temperature and its standard deviation (SD) affected long-term survival among the 13 million Medicare beneficiaries (aged 65+) in this region during 2000–2013. A 1 °C increase in summer mean temperature corresponded to an increase of 2.5% in death rate. Whereas, 1 °C increase in winter mean temperature was associated with a decrease of 1.5%. Increases in seasonal temperature SD also influence mortality. We decomposed seasonal mean temperature and its temperature SD into long-term geographic contrasts between ZIP codes and annual anomalies within ZIP code. Effect modifications by different subgroups were also examined to find out whether certain individuals are more vulnerable. Our findings will be critical to future efforts assessing health risks related to the future climate change.

  18. Reversal of Refractory Ulcerative Colitis and Severe Chronic Fatigue Syndrome Symptoms Arising from Immune Disturbance in an HLADR/DQ Genetically Susceptible Individual with Multiple Biotoxin Exposures

    Gunn, Shelly R.; Gibson Gunn, G.; Mueller, Francis W.

    2016-01-01

    Patient: Male, 25 Final Diagnosis: Ulcerative colitis and chronic fatigue syndrome Symptoms: Colitis • profound fatigue • multi-joint pain • cognitive impairment • corneal keratitis Medication: — Clinical Procedure: VIP replacement therapy Specialty: Family Medicine Objective: Unusual clinical course Background: Patients with multisymptom chronic conditions, such as refractory ulcerative colitis (RUC) and chronic fatigue syndrome (CFS), present diagnostic and management challenges for clinicians, as well as the opportunity to recognize and treat emerging disease entities. In the current case we report reversal of co-existing RUC and CFS symptoms arising from biotoxin exposures in a genetically susceptible individual. Case Report: A 25-year-old previously healthy male with new-onset refractory ulcerative colitis (RUC) and chronic fatigue syndrome (CFS) tested negative for autoimmune disease biomarkers. However, urine mycotoxin panel testing was positive for trichothecene group and air filter testing from the patient’s water-damaged rental house identified the toxic mold Stachybotrys chartarum. HLA-DR/DQ testing revealed a multisusceptible haplotype for development of chronic inflammation, and serum chronic inflammatory response syndrome (CIRS) biomarker testing was positive for highly elevated TGF-beta and a clinically undetectable level of vasoactive intestinal peptide (VIP). Following elimination of biotoxin exposures, VIP replacement therapy, dental extractions, and implementation of a mind body intervention-relaxation response (MBI-RR) program, the patient’s symptoms resolved. He is off medications, back to work, and resuming normal exercise. Conclusions: This constellation of RUC and CFS symptoms in an HLA-DR/DQ genetically susceptible individual with biotoxin exposures is consistent with the recently described CIRS disease pathophysiology. Chronic immune disturbance (turbatio immuno) can be identified with clinically available CIRS biomarkers and

  19. Uranium bone content as an indicator of chronic environmental exposure from drinking water

    Uranium (U) is an ubiquitous radioelement found in drinking water and food. As a consequence of its prevalence, most humans ingest a few micrograms (μg) of this element daily. It is incorporated in various organs and tissues. Several studies have demonstrated that ingested U is deposited mainly in bones. Therefore, U skeletal content could be considered as a prime indicator for low-level chronic intake. In this study, 71 archived vertebrae bone samples collected in seven Canadian cities were subjected to digestion and U analysis by inductively coupled plasma mass spectrometry. These results were correlated with U concentrations in municipal drinking water supplies, with the data originating from historical studies performed by Health Canada. A strong relationship (r2 = 0.97) was observed between the averaged U total skeletal content and averaged drinking water concentration, supporting the hypothesis that bones are indeed a good indicator of U intake. Using a PowerBASIC compiler to process an ICRP systemic model for U (ICRP, 1995a), U total skeletal content was estimated using two gastrointestinal tract absorption factors (f1 = 0.009 and 0.03). Comparisons between observed and modelled skeletal contents as a function of U intake from drinking water tend to demonstrate that neither of the f1 values can adequately estimate observed values. An f1value of 0.009 provides a realistic estimate for intake resulting from food consumption only (6.72 μg) compared to experimental data (7.4 ± 0.8 μg), whereas an f1value of 0.03 tends to better estimate U skeletal content at higher levels of U (1–10 μg L−1) in drinking water

  20. Apocynin prevents vascular effects caused by chronic exposure to low concentrations of mercury.

    Danize A Rizzetti

    Full Text Available UNLABELLED: Mercury increases the risk of cardiovascular disease and oxidative stress and alters vascular reactivity. This metal elicits endothelial dysfunction causing decreased NO bioavailability via increased oxidative stress and contractile prostanoid production. NADPH oxidase is the major source of reactive oxygen species (ROS in the vasculature. Our aim was to investigate whether treatment with apocynin, an NADPH oxidase inhibitor, prevents the vascular effects caused by chronic intoxication with low concentrations of mercury. Three-month-old male Wistar rats were treated for 30 days with a intramuscular injections (i.m. of saline; b HgCl(2 (i.m. 1(st dose: 4.6 µg/kg, subsequent doses: 0.07 µg/kg/day; c Apocynin (1.5 mM in drinking water plus saline i.m.; and d Apocynin plus HgCl(2. The mercury treatment resulted in 1 an increased aortic vasoconstrictor response to phenylephrine and reduced endothelium-dependent responses to acetylcholine; 2 the increased involvement of ROS and vasoconstrictor prostanoids in response to phenylephrine, whereas the endothelial NO modulation of such responses was reduced; and 3 the reduced activity of aortic superoxide dismutase (SOD and glutathione peroxidase (GPx and increased plasma malondialdehyde (MDA levels. Treatment with apocynin partially prevented the increased phenylephrine responses and reduced the endothelial dysfunction elicited by mercury treatment. In addition, apocynin treatment increased the NO modulation of vasoconstrictor responses and aortic SOD activity and reduced plasma MDA levels without affecting the increased participation of vasoconstrictor prostanoids observed in aortic segments from mercury-treated rats. CONCLUSIONS: Mercury increases the vasoconstrictor response to phenylephrine by reducing NO bioavailability and increasing the involvement of ROS and constrictor prostanoids. Apocynin protects the vessel from the deleterious effects caused by NADPH oxidase, but not from those

  1. Effects of chronic methamphetamine exposure on heart function in uninfected and retrovirus-infected mice.

    Yu, Qianli; Montes, Sergio; Larson, Douglas F; Watson, Ronald R

    2002-07-12

    Methamphetamine (MA) increases catecholamine levels, which have detrimental effects on heart function through vasoconstriction, myocardial hypertrophy, and fibrosis. Murine retrovirus infection induces dilated cardiomyopathy (DCM). The present study investigated the cardiovascular effects of chronic MA treatment on uninfected and retrovirus-infected mice. C57BL/6 mice were studied after 12 weeks treatment. The four study groups were (group I) uninfected, MA placebo; (group II) infected, MA placebo; (group III) uninfected, MA treatment; and (group IV) infected and MA treatment. MA injections were given i.p. once a day for 5 days/week with a increasing dose from 15 mg/kg to 40 mg/kg. Left ventricular mechanics were measured in situ a using Millar conductance catheter system for pressure-volume loop analysis. Cardiac pathology was determined with histological analysis. In the uninfected mice, the load independent contractile parameters, pre-load recruitable stroke work (PRSW) and dP/dt(max) vs. Ved, significantly decreased by 32% and 35% in MA treated mice when compared to the saline injected mice. In retrovirus-infected mice, although there were no significant difference in Ees, PRSW, and dP/dt(max) vs. Ved due to MA treatment, they were increased 45%, 15% and 42% respectively when compared to saline treated mice. No further lowered heart function during murine AIDS may be due to the counteraction of the retroviral DCM and the MA induced myocardial fibrosis and hypertrophy (thickening of the ventricular walls). This is supported by increases in the End-diastolic volume (Ved, 38%) and End-systolic volume (Ves, 84%) in the retrovirus-infected saline injected mice, the decreases of 33% and 17% in the uninfected MA-treated mice, but no significant changes in the retrovirus-infected MA treated mice when compared to uninfected saline injected mice. These data suggest that MA induced myocardial cellular changes compensate for retrovirus induced DCM. PMID:12084392

  2. Uptake of selenium by the unicellular green alga Chlamydomonas reinhardtii - effects induced by chronic exposure

    79Se is a long-lived radionuclide present in radioactive waste storages. The stable isotope selenium is an essential micro-nutrient that can act against oxidative damage. It is however well known for its bio-magnification potential and chemical toxicity to aquatic life. One of its particularity is to form oxyanions in freshwater ecosystems, which leads to specific behaviours towards biological membranes. Our study deals with the interactions between selenite -Se(IV)- and Chlamydomonas reinhardtii, a unicellular green alga representative of the freshwater phytoplankton community. Cells were exposed to selenite marked with Se75 in well-known simple inorganic media. Short-term experiments (about one hour of exposure) were performed to better understand selenite transport (uptake kinetics and levels) and identify main factors influencing absorption (nutrients concentrations, pH). Long-term experiments (4 days of exposure) were performed (1) to evaluate the bioaccumulation considering environmentally relevant time scales, (2) to localize the intracellular selenium using EDAX-TEM and (3) to assess the toxicity of selenium as measured by growth impairment, ultrastructural changes, starch accumulation, and loss of pigment. Short-term experiments revealed a time-dependent linear absorption with an estimated absorbed flux of about 0.25 nmol.m-2.nM-1.h-1. The absorption was proportional to ambient levels, except at very low concentrations (ca. 0.5 nM), were it was proportionally higher, suggesting that a specific but rapidly saturated transport could be used at those low concentrations. Selenite uptake was not dependent on phosphate nor carbonate concentrations. It was nevertheless inhibited by sulphate and nitrate, indicating that selenite could share common transporters with those nutrients. The accumulation was found to be maximum for intermediate pH around 7. EDAX-TEM analysis after long-term experiments revealed the presence of selenium in electron-dense granules. At end

  3. Chronic dietary exposure to pesticide residues and associated risk in the French ELFE cohort of pregnant women.

    de Gavelle, Erwan; de Lauzon-Guillain, Blandine; Charles, Marie-Aline; Chevrier, Cécile; Hulin, Marion; Sirot, Véronique; Merlo, Mathilde; Nougadère, Alexandre

    2016-01-01

    Dietary exposure to pesticide residues may present a risk to public health, especially for sensitive populations such as pregnant women. To characterize this risk, this study assessed chronic dietary exposure to pesticide residues based on the French ELFE cohort. A self-administered food frequency questionnaire (FFQ) about the last three months of pregnancy filled in by pregnant women in 2011 was used in combination with occurrence data from French Total Diet Studies completed by the results of national monitoring programs on pesticide residues in food. The dietary intake of pesticides (μg/kg of body weight/day) was estimated for 14,099 pregnant women with a complete FFQ, for 317 substances under two occurrence scenarios to handle left-censored data: a lower-bound scenario (LB), where undetected results were set to zero, and an upper-bound scenario (UB), where undetected results were set to the detection limit if the substance was expected to be found in food and zero if it was not. The risk was assessed for 284 substances with a toxicological reference value (TRV) and a good coverage level of the diet potentially contributing to pesticide intake. The cumulative risk was also assessed for seven effects on nervous and thyroid systems using the hazard index and the Cumulative Assessment Groups defined by EFSA. Substances with the highest exposure levels under the LB scenario were, in decreasing order, imazalil, piperonyl butoxide, chlorpropham, thiabendazole, iprodione and propargite. Under the LB scenario, only for lindane did women have a statistically significant probability of exceeding the TRV (2.4%). Under the UB scenario, risk could not be excluded for nine other substances. A better management of left-censored data and more sensitive analyses of the main food contributors might help to refine the UB exposure and risk assessments. A statistically significant cumulative risk was found for neurochemical effects related to high intake levels of three

  4. Development of asthmatic inflammation in mice following early-life exposure to ambient environmental particulates and chronic allergen challenge

    Cristan Herbert

    2013-03-01

    Childhood exposure to environmental particulates increases the risk of development of asthma. The underlying mechanisms might include oxidant injury to airway epithelial cells (AEC. We investigated the ability of ambient environmental particulates to contribute to sensitization via the airways, and thus to the pathogenesis of childhood asthma. To do so, we devised a novel model in which weanling BALB/c mice were exposed to both ambient particulate pollutants and ovalbumin for sensitization via the respiratory tract, followed by chronic inhalational challenge with a low mass concentration of the antigen. We also examined whether these particulates caused oxidant injury and activation of AEC in vitro. Furthermore, we assessed the potential benefit of minimizing oxidative stress to AEC through the period of sensitization and challenge by dietary intervention. We found that characteristic features of asthmatic inflammation developed only in animals that received particulates at the same time as respiratory sensitization, and were then chronically challenged with allergen. However, these animals did not develop airway hyper-responsiveness. Ambient particulates induced epithelial injury in vitro, with evidence of oxidative stress and production of both pro-inflammatory cytokines and Th2-promoting cytokines such as IL-33. Treatment of AEC with an antioxidant in vitro inhibited the pro-inflammatory cytokine response to these particulates. Ambient particulates also induced pro-inflammatory cytokine expression following administration to weanling mice. However, early-life dietary supplementation with antioxidants did not prevent the development of an asthmatic inflammatory response in animals that were exposed to particulates, sensitized and challenged. We conclude that injury to airway epithelium by ambient environmental particulates in early life is capable of promoting the development of an asthmatic inflammatory response in sensitized and antigen-challenged mice. These

  5. Oocyte loss in macaques from chronic tritiated water exposure before birth

    Because massive oocyte loss had been found in squirrel monkeys following low-level /sup 3/HOH exposure prenatally, two species of macaque, rhesus and bonnet monkeys (Macaca mulatta and M. radiata), were studied to test whether intense germ-cell radiosensitivity exists also in other primates before birth (hence perhaps in man). Adult females received 5 μCi/ml of /sup 3/HOH in drinking water from the time pregnancy was hormonally confirmed until shortly after parturition, giving measured body-water levels of 4 μCi/ml, delivering 0.9 rad/day. From the female offspring, ovaries were removed soon after birth and at 6 months; oocytes were enumerated in serial sections. In the newborns, germ-cell deficiencies (comparisons with controls) were about 20%, much less than seen in squirrel monkeys. By 6 months, however, losses were striking: 60% in rhesus and 95% in bonnet monkeys. Such losses, from less than 1 rad/day and seen varyingly in all three primate species examined, warn of possible high prenatal germ-cell vulnerability in the human female

  6. Cocaine-conditioned odor cues without chronic exposure: Implications for the development of addiction vulnerability

    Steven B. Lowen

    2015-01-01

    Full Text Available Adolescents are highly vulnerable to addiction and are four times more likely to become addicted at first exposure than at any other age. The dopamine D1 receptor, which is typically overexpressed in the normal adolescent prefrontal cortex, is involved in drug cue responses and is associated with relapse in animal models. In human drug addicts, imaging methods have detected increased activation in response to drug cues in reward- and habit-associated brain regions. These same methods can be applied more quantitatively to rodent models. Here, changes in neuronal activation in response to cocaine-conditioned cues were observed using functional magnetic resonance imaging in juvenile rats that were made to over-express either D1 receptors or green fluorescent protein by viral-mediated transduction. Reduced activation was observed in the amygdala and dopamine cell body regions in the low cue-preferring/control juvenile rats in response to cocaine cues. In contrast, increased activation was observed in the dorsal striatum, nucleus accumbens, prefrontal cortex, and dopamine cell bodies in high cue-preferring/D1 juveniles. The increase in cue salience that is mediated by increased D1 receptor density, rather than excessive cocaine experience, appears to underlie the transition from aversion to reward in cue-induced neural response and may form the basis for habit-forming vulnerability.

  7. Cocaine-conditioned odor cues without chronic exposure: Implications for the development of addiction vulnerability.

    Lowen, Steven B; Rohan, Michael L; Gillis, Timothy E; Thompson, Britta S; Wellons, Clara B W; Andersen, Susan L

    2015-01-01

    Adolescents are highly vulnerable to addiction and are four times more likely to become addicted at first exposure than at any other age. The dopamine D1 receptor, which is typically overexpressed in the normal adolescent prefrontal cortex, is involved in drug cue responses and is associated with relapse in animal models. In human drug addicts, imaging methods have detected increased activation in response to drug cues in reward- and habit-associated brain regions. These same methods can be applied more quantitatively to rodent models. Here, changes in neuronal activation in response to cocaine-conditioned cues were observed using functional magnetic resonance imaging in juvenile rats that were made to over-express either D1 receptors or green fluorescent protein by viral-mediated transduction. Reduced activation was observed in the amygdala and dopamine cell body regions in the low cue-preferring/control juvenile rats in response to cocaine cues. In contrast, increased activation was observed in the dorsal striatum, nucleus accumbens, prefrontal cortex, and dopamine cell bodies in high cue-preferring/D1 juveniles. The increase in cue salience that is mediated by increased D1 receptor density, rather than excessive cocaine experience, appears to underlie the transition from aversion to reward in cue-induced neural response and may form the basis for habit-forming vulnerability. PMID:27006904

  8. Sampling strategies for estimating acute and chronic exposures of pesticides in streams

    Crawford, Charles G.

    2004-01-01

    The Food Quality Protection Act of 1996 requires that human exposure to pesticides through drinking water be considered when establishing pesticide tolerances in food. Several systematic and seasonally weighted systematic sampling strategies for estimating pesticide concentrations in surface water were evaluated through Monte Carlo simulation, using intensive datasets from four sites in northwestern Ohio. The number of samples for the strategies ranged from 4 to 120 per year. Sampling strategies with a minimal sampling frequency outside the growing season can be used for estimating time weighted mean and percentile concentrations of pesticides with little loss of accuracy and precision, compared to strategies with the same sampling frequency year round. Less frequent sampling strategies can be used at large sites. A sampling frequency of 10 times monthly during the pesticide runoff period at a 90 km 2 basin and four times monthly at a 16,400 km2 basin provided estimates of the time weighted mean, 90th, 95th, and 99th percentile concentrations that fell within 50 percent of the true value virtually all of the time. By taking into account basin size and the periodic nature of pesticide runoff, costs of obtaining estimates of time weighted mean and percentile pesticide concentrations can be minimized.

  9. Trends in Pinus ponderosa foliar pigment concentration due to chronic exposure of ozone and acid rain

    To determine the effects of ozone and acid rain on mature Ponderosa pine trees, Lawrence Livermore National Lab. has collaborated with University of California Berkeley, University of California Davis, California State University Chico, and the US Forest Service at the latter's Chico Tree Improvement Center. Foliar tissue from mature grafted scions of Pinus ponderosa were exposed to two times ambient ozone for ten months and to acid rain (3.0 pH) weekly for 10 weeks using branch exposure chambers. Pigment extracts were analyzed spectrophotometrically for concentrations of chlorophylls a and b, and carotenoid pigments, at 662 nm, 644 nm, and 470 nm, respectively. Pigment concentrations were expressed on a surface area basis. Preliminary results revealed that chlorophyll a showed a downward trend due to the ozone treatment. Acid rain caused no effects on these three pigments, however, chlorophyll b showed an upward trend due to the interaction of ozone and acid rain. The carotenoid pigments showed no changes due to the treatments either singly, or in combination

  10. CD44v6 expression in human skin keratinocytes as a possible mechanism for carcinogenesis associated with chronic arsenic exposure

    S. Huang

    2013-01-01

    Full Text Available Inorganic arsenic is a well-known human skin carcinogen. Chronic arsenic exposure results in various types of human skin lesions, including squamous cell carcinoma (SCC. To investigate whether mutant stem cells participate in arsenic-associated carcinogenesis, we repeatedly exposed the HaCaT cells line to an environmentally relevant level of arsenic (0.05 ppm in vitro for 18 weeks. Following sodium arsenic arsenite administration, cell cycle, colony-forming efficiency (CFE, cell tumorigenicity, and expression of CD44v6, NF-κB and p53, were analyzed at different time points (0, 5, 10, 15, 20, 25 and 30 passages. We found that a chronic exposure of HaCaT cells to a low level of arsenic induced a cancer stem- like phenotype. Furthermore, arsenic-treated HaCaT cells also became tumorigenic in nude mice, their growth cycle was predominantly in G2/M and S phases. Relative to nontreated cells, they exhibited a higher growth rate and a significant increase in CFE. Western blot analysis found that arsenic was capable of increasing cell proliferation and sprouting of cancer stem-like phenotype. Additionally, immunohistochemical analysis demonstrated that CD44v6 expression was up-regulated in HaCaT cells exposed to a low level of arsenic during early stages of induction. The expression of CD44v6 in arsenic-treated cells was positively correlated with their cloning efficiency in soft agar (r=0.949, P=0.01. Likewise, the expressions of activating transcription factor NF-κB and p53 genes in the arsenic-treated HaCaT cells were significantly higher than that in non-treated cells. Higher expressions of CD44v6, NF-κB and p53 were also observed in tumor tissues isolated from Balb/c nude mice. The present results suggest that CD44v6 may be a biomarker of arsenic-induced neoplastic transformation in human skin cells, and that arsenic promotes malignant transformation in human skin lesions through a NF-κB signaling pathway-stimulated expression of CD44v6.

  11. Chronic lead exposure decreases the vascular reactivity of rat aortas: the role of hydrogen peroxide.

    Karolini Zuqui Nunes

    Full Text Available We investigated whether exposure to small concentrations of lead alters blood pressure and vascular reactivity. Male Wistar rats were sorted randomly into the following two groups: control (Ct and treatment with 100 ppm of lead (Pb, which was added to drinking water, for 30 days. Systolic blood pressure (BP was measured weekly. Following treatment, aortic ring vascular reactivity was assessed. Tissue samples were properly stored for further biochemical investigation. The lead concentration in the blood reached approximately 8 μg/dL. Treatment increased blood pressure and decreased the contractile responses of the aortic rings to phenylephrine (1 nM-100 mM. Following N-nitro-L arginine methyl ester (L-NAME administration, contractile responses increased in both groups but did not differ significantly between them. Lead effects on Rmax were decreased compared to control subjects following superoxide dismutase (SOD administration. Catalase, diethyldithiocarbamic acid (DETCA, and apocynin increased the vasoconstrictor response induced by phenylephrine in the aortas of lead-treated rats but did not increase the vasoconstrictor response in the aortas of untreated rats. Tetraethylammonium (TEA potentiated the vasoconstrictor response induced by phenylephrine in aortic segments in both groups, but these effects were greater in lead-treated rats. The co-incubation of TEA and catalase abolished the vasodilatory effect noted in the lead group. The present study is the first to demonstrate that blood lead concentrations well below the values established by international legislation increased blood pressure and decreased phenylephrine-induced vascular reactivity. The latter effect was associated with oxidative stress, specifically oxidative stress induced via increases in hydrogen peroxide levels and the subsequent effects of hydrogen peroxide on potassium channels.

  12. Sub-chronic exposure to fluoxetine in juvenile oysters (Crassostrea gigas): uptake and biological effects.

    Di Poi, Carole; Evariste, Lauris; Séguin, Alexis; Mottier, Antoine; Pedelucq, Julie; Lebel, Jean-Marc; Serpentini, Antoine; Budzinski, Hélène; Costil, Katherine

    2016-03-01

    The bioconcentration potential of fluoxetine (FLX) and its biological effects were investigated in juvenile Pacific oyster exposed for 28 days to environmentally relevant concentrations of FLX (1 ng L(-1), 100 ng L(-1) and up to 10 μg L(-1)). FLX bioaccumulated in oyster flesh resulting in 28-day bioconcentration factors greater than 2,000 and 10,000 by referring to wet and dry weights, respectively. Nevertheless, FLX did not induce oyster mortality, delayed gametogenesis, or lead to adverse histopathological alterations. At the two highest concentrations, despite non-optimal trophic conditions, FLX stimulated shell growth but only in a transient manner, suggesting a role of serotonin in the regulation of feeding and metabolism in bivalves. Those high concentrations seemed to drive bell-shaped responses of catalase and glutathione S-transferase activities throughout the exposure period, which may indicate the activation of antioxidant enzyme synthesis and then an enhanced catabolic rate or direct inhibition of those enzymes. However, no clear oxidative stress was detected because no strong differences in thiobarbituric acid-reactive substance (TBARS) content (i.e. lipid peroxidation) were observed between oyster groups, suggesting that cellular defence mechanisms were effective. These results demonstrate the importance of considering additional biomarkers of oxidative stress to obtain a comprehensive overview of the FLX-induced changes in marine bivalves exposed under realistic conditions. Considering the battery of biomarkers used, FLX appears to induce little or no effects on oyster physiology even at a concentration of 10 μg L(-1). These results do not confirm the lowest observed effect concentration (LOEC) values reported by some authors in other mollusc species. PMID:25315935

  13. Effect of chronic selenium exposure on the freshwater bivalve Corbicula fluminea

    Selenium is essential for most of living organisms. In oxic to moderately oxic fresh-waters, Se exists predominantly in the (+VI) and (+IV) oxidation states as selenate (SeO42-) and selenite (SeO32-) respectively, whereas in the biota it is incorporated as Se(-II) into seleno-proteins or amino-acids, or as elemental selenium Se(0). At low concentrations, it acts against oxidative damages mainly as the glutathione peroxidase seleno-dependant, but it may be toxic at higher levels (for example, by replacing sulphur in important biomolecules). In filter feeders, such as the freshwater bivalve Corbicula fluminea, selected as biological model, the ventilation activity is a primary limiting step that controls the water influx and therefore the delivery of contaminants. Consequently, a series of short-term experiments were performed to study the effects of different dissolved Se concentrations and forms (selenite; selenate; selenomethionine) on the ventilation activity of Corbicula fluminea and Se tissular distribution. The modification of the ventilation activity of the Se-exposed groups, in comparison to this of reference groups (not exposed to Se) varied greatly according to the form and the concentrations of the Se used. Se concentrations in tissues indicated that selenite was the less bioavailable form whereas selenomethionine displayed the opposite trend. On the basis of this set of experiments, a limited number of conditions have been selected to provide highly contrasting ventilation flow rates and selenium bioaccumulation levels, in order to study the effects of long term exposures, i) at the molecular level, by measuring bio-markers of oxidative stress (forms of glutathione, glutathione peroxidase, glutathione reductase, superoxide dismutase, catalase, and bio-marker of genotoxicity (comet assay), ii) at the (sub)cellular level by analysing Se micro-localisation in target organs and iii) at the individual level by monitoring the variation in the ventilatory flow

  14. ACSL6 is associated with the number of cigarettes smoked and its expression is altered by chronic nicotine exposure.

    Jingchun Chen

    Full Text Available Individuals with schizophrenia tend to be heavy smokers and are at high risk for tobacco dependence. However, the nature of the comorbidity is not entirely clear. We previously reported evidence for association of schizophrenia with SNPs and SNP haplotypes in a region of chromosome 5q containing the SPEC2, PDZ-GEF2 and ACSL6 genes. In this current study, analysis of the control subjects of the Molecular Genetics of Schizophrenia (MGS sample showed similar pattern of association with number of cigarettes smoked per day (numCIG for the same region. To further test if this locus is associated with tobacco smoking as measured by numCIG and FTND, we conducted replication and meta-analysis in 12 independent samples (n>16,000 for two markers in ACSL6 reported in our previous schizophrenia study. In the meta-analysis of the replication samples, we found that rs667437 and rs477084 were significantly associated with numCIG (p = 0.00038 and 0.00136 respectively but not with FTND scores. We then used in vitro and in vivo techniques to test if nicotine exposure influences the expression of ACSL6 in brain. Primary cortical culture studies showed that chronic (5-day exposure to nicotine stimulated ACSL6 mRNA expression. Fourteen days of nicotine administration via osmotic mini pump also increased ACSL6 protein levels in the prefrontal cortex and hippocampus of mice. These increases were suppressed by injection of the nicotinic receptor antagonist mecamylamine, suggesting that elevated expression of ACSL6 requires nicotinic receptor activation. These findings suggest that variations in the ACSL6 gene may contribute to the quantity of cigarettes smoked. The independent associations of this locus with schizophrenia and with numCIG in non-schizophrenic subjects suggest that this locus may be a common liability to both conditions.

  15. Triglyceride accumulation in long-term cultures of adult rat hepatocytes by chronic exposure to Aroclor 1254

    The effect of chronic exposure to micromolar concentrations of Aroclor 1254 (Aro) on the hepatic lipid metabolism was studied in long-term cultures of adult rat hepatocytes. Hepatocytes were cocultivated with mytomicin C-treated 3T3 cells and exposed for 2 wk to Aroclor 1254 concentrations ranging from 0.01 to 20 μg/ml. The Aro-exposed cultures showed intracytoplasmic lipid droplets and a maximum increase of 55% in the triglyceride (TG) content and of 4.4-fold in the cytochrome P-450 content. Labeling studies with [14C]acetic and [14C]oleic acid showed no changes in the uptake of fatty acid and TG precursors by the Aro-treated cultures; the synthesis of cellular lipids from [14C]acetic acid was slightly inhibited by Aroclor 1254, but that from [14C]oleic acid was increased, specially for TF (37%). The secretion of total lipids and TG was 2.1- and 2.7-fold lower, respectively, in the cultures treated with 20 μg/ml of Aroclor 1254, resulting in an increase of 1.9-fold in the intracellular content of TG. The synthesis of cellular proteins labeled with [3H]leucine was unchanged in the Aro-treated cultures, but the secretion of exportable proteins was 1.7-fold lower in the cultures treated with 20 μg/ml of Aroclor 1254. Our results showed that long-term exposure to in vivo relevant concentrations of Aroclor 1254 produced morphological and biochemical changes in cultured hepatocytes, like those described in vivo, and intracellular TG accumulation due mostly to impaired secretion of TG by the hepatocytes. Our results also suggest that this culture system could be useful for the screening of toxic agents producing fatty liver and the study of the involved mechanism(s)

  16. Effects of chronic exposure in populations of Koeleria gracilis Pers. from the Semipalatinsk nuclear test site, Kazakhstan

    Morphological and cytogenetic abnormalities were examined in crested hairgrass (Koeleria gracilis Pers.) populations inhabiting the Semipalatinsk nuclear test site (STS), Kazakhstan. Sampling of biological material and soil was carried out during 3 years (2005–2007) at 4 sites within the STS. Activity concentrations of 10 radionuclides and 8 heavy metals content in soils were measured. Doses absorbed by plants were estimated and varied, depending on the plot, from 4 up to 265 mGy/y. The frequency of cytogenetic alterations in apical meristem of germinated seeds from the highly contaminated plot significantly exceeded the level observed at other plots with lower levels of radioactive contamination during all three years of the study. A significant excess of chromosome aberrations, typical for radiation exposure, as well as a dependence of the frequency of these types of mutations on dose absorbed by plants were revealed. The results indicate the role radioactive contamination plays in the occurrence of cytogenetic effects. However, no radiation-dependent morphological alterations were detected in the progeny of the exposed populations. Given that the crested hairgrass populations have occupied the radioactively contaminated plots for some 50 years, adaptation to the radiation stress was not evident. The findings obtained were in agreement with the benchmark values proposed in the FASSET and ERICA projects to restrict radiation impacts on biota. - Highlights: ► Morphological and cytogenetic abnormalities were examined in plants from the STS. ► Annual doses absorbed by plants varied from 4 up to 265 mGy. ► Cytogenetic alterations in plants from the explosions epicenter exceeded the control. ► No radiation-dependent morphological alterations were detected in the progeny. ► Radio-adaptation in plant populations in 50 years of chronic exposure was not evident.

  17. Physiological Predictors of Response to Exposure, Relaxation, and Rescripting Therapy for Chronic Nightmares in a Randomized Clinical Trial

    Davis, Joanne L.; Rhudy, Jamie L.; Pruiksma, Kristi E.; Byrd, Patricia; Williams, Amy E.; McCabe, Klanci M.; Bartley, Emily J.

    2011-01-01

    Study Objectives: Evidence supports the use of cognitive behavioral therapies for nightmares in trauma-exposed individuals. This randomized clinical trial replicated a study of exposure, relaxation, and rescripting therapy(ERRT) and extended prior research by including broad measures of mental health difficulties, self-reported physical health problems, and quality of life. Additionally, physiological correlates of treatment-related change assessed from a script-driven imagery paradigm were examined. Methods: Forty-seven individuals were randomized to treatment or waitlist control. Results: The treatment group demonstrated improvements relative to the control group at the one-week post-treatment assessment. At the 6-month follow-up assessment, significant improvements were found for frequency and severity of nightmares, posttraumatic stress disorder symptoms, depression, sleep quality and quantity, physical health symptoms, anger, dissociation, and tension reduction behaviors. Participants also reported improved quality of life. Treatment-related decreases in heart rate to nightmare imagery were correlated with improvements in sleep quality and quantity; treatment-related decreases in skin conductance to nightmare imagery were correlated with improvements in nightmare severity, posttraumatic stress disorder symptom severity, sleep quality, and fear of sleep; and treatment-related decreases in corrugator activity to nightmare imagery were correlated with improved physical health. Conclusions: Findings provide additional support for the use of ERRT in treating nightmares and related difficulties and improving sleep. Citation: Davis JL; Rhudy JL; Pruiksma KE; Byrd P; Williams AE; McCabe KM; Bartley EJ. Physiological predictors of response to exposure, relaxation, and rescripting therapy for chronic nightmares in a randomized clinical trial. J Clin Sleep Med 2011;7(6):622-631. PMID:22171201

  18. Effects of chronic prenatal ethanol exposure on locomotor activity, and hippocampal weight, neurons, and nitric oxide synthase activity of the young postnatal guinea pig.

    Gibson, M A; Butters, N S; Reynolds, J N; Brien, J F

    2000-01-01

    Decreased nitric oxide synthase (NOS)-catalyzed formation of NO from L-arginine may be involved in ethanol teratogenesis involving the hippocampus. This hypothesis was tested by determining the effects of chronic prenatal ethanol exposure on locomotor activity and on hippocampal weight, number of CA1 and CA3 pyramidal cells and dentate gyrus granule cells, and NOS activity of the postnatal guinea pig. Timed, pregnant guinea pigs received one of the following chronic oral regimens throughout gestation: 4 g ethanol/kg maternal body weight/day, isocaloric-sucrose/pair-feeding, or water. At postnatal day (PD) 10, spontaneous locomotor activity was measured. At PD 12, histological analysis was performed on the hippocampal formation, in which hippocampal CA1 and CA3 pyramidal cells and dentate gyrus granule cells were counted; body, brain, and hippocampal weights were measured; and hippocampal NOS enzymatic activity was determined using a radiometric assay. Chronic prenatal ethanol exposure produced hyperactivity, decreased the brain and hippocampal weights with no change in body weight, decreased the number of hippocampal CA1 pyramidal cells by 25-30%, and had no effect on hippocampal NOS activity compared with the two control groups. These data, together with our previous findings in the fetal guinea pig, demonstrate that chronic prenatal ethanol exposure decreases hippocampal NOS activity in near-term fetal life that temporally precedes the selective loss of hippocampal CA1 pyramidal cells in postnatal life. PMID:10758347

  19. Hepatic and renal trace element concentrations in American alligators (Alligator mississippiensis) following chronic dietary exposure to coal fly ash contaminated prey.

    Tuberville, Tracey D; Scott, David E; Metts, Brian S; Finger, John W; Hamilton, Matthew T

    2016-07-01

    Little is known about the propensity of crocodilians to bioaccumulate trace elements as a result of chronic dietary exposure. We exposed 36 juvenile alligators (Alligator mississippiensis) to one of four dietary treatments that varied in the relative frequency of meals containing prey from coal combustion waste (CCW)-contaminated habitats vs. prey from uncontaminated sites, and evaluated tissue residues and growth rates after 12 mo and 25 mo of exposure. Hepatic and renal concentrations of arsenic (As), cadmium (Cd) and selenium (Se) varied significantly among dietary treatment groups in a dose-dependent manner and were higher in kidneys than in livers. Exposure period did not affect Se or As levels but Cd levels were significantly higher after 25 mo than 12 mo of exposure. Kidney As and Se levels were negatively correlated with body size but neither growth rates nor body condition varied significantly among dietary treatment groups. Our study is among the first to experimentally examine bioaccumulation of trace element contaminants in crocodilians as a result of chronic dietary exposure. A combination of field surveys and laboratory experiments will be required to understand the effects of different exposure scenarios on tissue residues, and ultimately link these concentrations with effects on individual health. PMID:27149145

  20. Lung nodules accidentally detected on CT scans

    Improving of the spatial resolution of modern CT scanners has increased the amount of information obtained by lung CT, and thus the amount of accidentally determined nodules and quality of their structure specification. To unify the criteria of their follow-up CT studies Fleischner Society has issued recommendations for management of solid pulmonary nodules, and then added recommendations for subsolid nodules. In this article the review of categories of such accidental findings in lungs is presented with follow-up criteria and annotations applied

  1. Reversal of Refractory Ulcerative Colitis and Severe Chronic Fatigue Syndrome Symptoms Arising from Immune Disturbance in an HLA-DR/DQ Genetically Susceptible Individual with Multiple Biotoxin Exposures.

    Gunn, Shelly R; Gunn, G Gibson; Mueller, Francis W

    2016-01-01

    BACKGROUND Patients with multisymptom chronic conditions, such as refractory ulcerative colitis (RUC) and chronic fatigue syndrome (CFS), present diagnostic and management challenges for clinicians, as well as the opportunity to recognize and treat emerging disease entities. In the current case we report reversal of co-existing RUC and CFS symptoms arising from biotoxin exposures in a genetically susceptible individual. CASE REPORT A 25-year-old previously healthy male with new-onset refractory ulcerative colitis (RUC) and chronic fatigue syndrome (CFS) tested negative for autoimmune disease biomarkers. However, urine mycotoxin panel testing was positive for trichothecene group and air filter testing from the patient's water-damaged rental house identified the toxic mold Stachybotrys chartarum. HLA-DR/DQ testing revealed a multisusceptible haplotype for development of chronic inflammation, and serum chronic inflammatory response syndrome (CIRS) biomarker testing was positive for highly elevated TGF-beta and a clinically undetectable level of vasoactive intestinal peptide (VIP). Following elimination of biotoxin exposures, VIP replacement therapy, dental extractions, and implementation of a mind body intervention-relaxation response (MBI-RR) program, the patient's symptoms resolved. He is off medications, back to work, and resuming normal exercise. CONCLUSIONS This constellation of RUC and CFS symptoms in an HLA-DR/DQ genetically susceptible individual with biotoxin exposures is consistent with the recently described CIRS disease pathophysiology. Chronic immune disturbance (turbatio immuno) can be identified with clinically available CIRS biomarkers and may represent a treatable underlying disease etiology in a subset of genetically susceptible patients with RUC, CFS, and other immune disorders. PMID:27165859

  2. Ameliorative effect of polydatin on oxidative stress-mediated testicular damage by chronic arsenic exposure in rats.

    Ince, S; Avdatek, F; Demirel, H H; Arslan-Acaroz, D; Goksel, E; Kucukkurt, I

    2016-06-01

    Arsenic causes lipid peroxidation leading to alterations in antioxidant status in organisms. In this study, the reproductive effects of chronic exposure to arsenic and the protective effects of polydatin (PD) were evaluated in 35 Wistar male rats, which were divided equally into five groups. The control group received a normal diet and tap water, arsenic (100 mg l(-1) , approximately 1/50 of oral LD50 ) was given via drinking water to experimental groups except control group, and PD was orally given to the other groups at dose of 50, 100 and 200 mg kg(-1) for 60 days. Arsenic administration decreased sperm motility, glutathione level, superoxide dismutase and catalase activities in testicular tissue of rats. In contrast, malondialdehyde level and DNA damage were found to be high levels in arsenic-treated group. Histopathologically, it was observed that decreased sperm concentration and degeneration of Sertoli cells in testicular tissue. PD administration, partially 200 mg kg(-1) , reversed arsenic-induced lipid peroxidation, DNA damage, antioxidant enzyme activity and cell integrity in testis of rats. These results demonstrate that PD decreases arsenic-induced lipid peroxidation, enhances the antioxidant defence mechanism and regenerates tissue damage in testis of rats. PMID:26302725

  3. Effects of chronic exposure to benzalkonium chloride in Oncorhynchus mykiss: cholinergic neurotoxicity, oxidative stress, peroxidative damage and genotoxicity.

    Antunes, S C; Nunes, B; Rodrigues, S; Nunes, R; Fernandes, J; Correia, A T

    2016-07-01

    Benzalkonium chloride (BAC) is one of the most used conservatives in pharmaceutical preparations. However, its use is limited to a small set of external use formulations, due to its high toxicity. Benzalkonium chloride effects are related to the potential exertion of deleterious effects, mediated via oxidative stress and through interaction with membrane enzymes, leading to cellular damage. To address the ecotoxicity of this specific compound rainbow trouts were chronically exposed to BAC at environmental relevant concentrations (ranging from 0.100 to 1.050mg/L), and the biological response of cholinergic neurotoxicity, modulation of the antioxidant defense, phase II metabolism, lipid peroxidation and genotoxicity was studied. The obtained results showed a dual pattern of antioxidant response, with significant alterations in catalase activity (starting at 0.180mg/L), and lipid peroxidation, for intermediate (0.180 and 0.324mg/L) concentrations. No significant alterations occurred for glutathione-S-transferases activity. An unexpected increased of the acetylcholinesterase activity was also recorded for the individuals exposed to higher concentrations of BAC (starting at 0.180mg/L). Furthermore, exposure to BAC resulted in the establishment of genotoxic alterations, observable (for the specific case of the comet assay results) for all tested BAC concentrations. However, and considering that the oxidative response was not devisable, other mechanisms may be involved in the genotoxic effects reported here. PMID:27280532

  4. Metabonomic analysis of quercetin against the toxicity of chronic exposure to a mixture of four organophosphate pesticides in rat plasma.

    Cao, Can; Zeng, Yan; Shi, Haidan; Yang, Shuang; Bao, Wei; Qi, Lei; Liu, Ying; Zhao, Xiujun

    2016-09-01

    1. A metabonomics approach was performed to investigate the effect of quercetin on the toxicity of chronic exposure to a mixture of four organophosphate pesticides (OPs) at their corresponding no-observed-adverse-effect level (NOAEL). The rats were divided into six groups (n = 10/group): control, two different doses of quercetin, OPs mixture and different doses of quercetin plus OPs mixture-treated groups. 2. Nine metabolites, including two quercetin metabolites and seven endogenous metabolites were identified in plasma. The intensities of metabolites significantly changed in the OP mixture-treated group compared with the control group (p < 0.01), such as lysoPE (16:0/0:0), lysoPC (17:0/0:0), lysoPC (15:0/0:0) and 4-pyridoxic acid, significantly increased; by contrast, the intensities of arachidonic acid and citric acid significantly decreased. Anomalous intensity changes in aforementioned metabolites were alleviated in the OP mixture plus 50 mg/kgċbw/d quercetin-treated group compared with the OP mixture-treated group (p < 0.05). 3. The results indicated that quercetin elicited partial protective effects against the toxicity induced by a mixture of OPs, which include regulation of lipid metabolism, improvement of tricarboxylic acid (TCA) cycle disorders, enhancement of antioxidant defence system to protect the liver. PMID:26677787

  5. Low level exposure to cadmium increases the risk of chronic kidney disease: analysis of the NHANES 1999-2006

    Sturniolo Antonio

    2010-06-01

    Full Text Available Abstract Background Environmental factors have been associated with the outbreak of chronic kidney disease (CKD. We evaluated the association of Cadmium (Cd exposure with the risk of CKD in U.S. adults who participated in the 1999-2006 National Health and Nutrition Examination Surveys (NHANES. Methods 5426 subjects ≥ 20 years were stratified for values of urinary and blood Cd and a multivariate logistic regression was performed to test the association between blood and urinary Cd, CKD and albuminuria (ALB after adjustment for age, gender, race/ethnicity, body mass index and smoking habits. Results Subjects with urinary Cd > 1 mcg/g and subjects with blood Cd > 1 mcg/L showed a higher association with ALB (OR 1.63, 95% CI 1.23, 2.16; P = 0.001. Subjects with blood Cd > 1 mcg/L showed a higher association with both CKD (OR 1.48, 95% CI 1.01, 2.17; P = 0.046 and ALB (OR 1.41, 95% CI 1.10, 1.82; P = 0.007. An interaction effect on ALB was found for high levels of urinary and blood Cd (P = 0.014. Conclusions Moderately high levels of urinary and blood Cd are associated with a higher proportion of CKD and ALB in the United States population.

  6. Prenatal exposure to maternal voluntary exercise during pregnancy provides protection against mild chronic postnatal hypoxia in rat offspring.

    Akhavan, Maziar Mohammad; Foroutan, Tahereh; Safari, Manouchehr; Sadighi-Moghaddam, Bizhan; Emami-Abarghoie, Mitra; Rashidy-Pour, Ali

    2012-01-01

    Postnatal hypoxia is a main cause of neuronal damage in newborn. However, our understanding of the possible preventive or therapeutic methods to reduce the harmful effects of hypoxia is still primary. Pregnant rats were provided with running wheels during their pregnancy. On PND4 (postnatal day 4)to PND8, the rat pups were exposed to postnatal chronic hypoxia (11% O(2), 89% N(2)) in an air-tight plastic chamber for a period of six hours per day. The number of neurons and also angiogenesis in hippocampus were studied. Postnatal exposure to mild hypoxia decreased the number of the neurons in all studied regions of the hippocampus CA1, CA3 (cornu ammonis), DG(dentate gyrus) and SUB(cubiculum) in rat pups. In other words the number of the neurons in rat pups born from voluntary exercise group was not significantly less than control group in CA1, CA3 and DG regions. So maternal Voluntary exercise during pregnancy increases the blood vessel density in the DG region of the hippocampus of the rat pups. In this study for the first time we provide evidences that show the protective effect of maternal voluntary exercise during pregnancy on rat offspring against postnatal hypoxia. We revealed that maternal exercise during pregnancy increases the hippocampal neuron number and angiogenesis in offspring. PMID:22186335

  7. DNA-damage response associated with occupational exposure, age and chronic inflammation in workers in the automotive industry.

    Savina, Natalya V; Smal, Marharyta P; Kuzhir, Tatyana D; Ershova-Pavlova, Alla A; Goncharova, Roza I

    2012-10-01

    The evaluation of genome integrity in populations occupationally exposed to combine industrial factors is of medical importance. In the present study, the DNA-damage response was estimated by means of the alkaline comet assay in a sizeable cohort of volunteers recruited among workers in the automotive industry. For this purpose, freshly collected lymphocytes were treated with hydrogen peroxide (100μM, 1min, 4°C) in vitro, and the levels of basal and H(2)O(2)-induced DNA damage, and the kinetics and efficiency of DNA repair were measured during a 180-min interval after exposure. The parameters studied in the total cohort of workers were in a range of values prescribed for healthy adult residents of Belarus. Based on the 95th percentiles, individuals possessing enhanced cellular sensitivity to DNA damage were present in different groups, but the frequency was significantly higher among elderly persons and among individuals with chronic inflammatory diseases. The results indicate that the inter-individual variations in DNA-damage response should be taken into account to estimate adequately the environmental genotoxic effects and to identify individuals with an enhanced DNA-damage response due to the influence of some external factors or intrinsic properties of the organism. Underling mechanisms need to be further explored. PMID:22772077

  8. Tuberculosis cutánea por inoculación accidental Cutaneous tuberculosis accidental inoculation

    María Ascensión Maestre Naranjo; Jenry Borda Olivas; Arantxa Ortega Hernández; Esmeralda Tovar Benito; María Luisa Rodríguez de la Pinta; Rosa María Daza Pérez

    2009-01-01

    Caso clínico de una microbióloga con amplia experiencia, que sufre una inoculación accidental al manipular una cepa pura de Mycobacterium tuberculosis. Se pincha en la cara lateral externa de la falange distal del dedo índice, atravesando el guante con la aguja contaminada. (Imagen 1). La trabajadora procede de forma inmediata a la limpieza de la herida. El Servicio de Prevención, registra la inoculación como accidente de trabajo. A las tres semanas del accidente, aparece en el lugar de la in...

  9. Doctrinal elements for the post-accidental management of a nuclear accident - Final version

    This report examines and defines the objectives, principles and main actions for the post-accidental management of a nuclear accident. It defines the emergency phase and the post-accidental phase, three basic objectives (to protect the population against the hazards of ionizing radiations, to support populations affected by the accident consequences, to restore affected territories), management principles, key issues for post-accidental management. It defines actions to be undertaken: post-accidental zoning, monitoring of deposited radioactivity, early actions for the protection and taking charge of population, information. It addresses the different aspects of post-accidental management planning in a period of transition: reception of population, reduction of population exposure to deposited radioactivity, treatment of public health problems, improvement of the knowledge on the radiological situation of the environment, improvement of the radiological quality of the different environments, dealing with wastes, empowerment of stakeholders through an adequate governance, support and redeployment of economic activity, help and compensation, information. Appendices more deeply discuss actions to be undertaken just after the emergency phase, for the management of the transition period, and for the management of the long-term period

  10. Constitution of a group of Czech and French uranium miners in order to estimate lung cancer risk linked to low chronic exposure to radon decay products

    West Bohemian and French uranium miners are characterized by a long duration of exposure to radon and its decay products, in comparison to most of the other groups of miners, studied in the recent international joint analysis by the National Cancer Institute (NCI) in USA. This analysis has confirmed the linearly increasing risk of lung cancer by cumulative radon exposure, describing the different factors that may influence this dose-response relationship. One of the main factors presently discussed is the influence of the exposure-rate effect: in other words, has the same cumulated exposure spread over 10 years the same risk of lung cancer as if it is cumulated in 2 years? The implication of an inverse exposure-rate effect for low chronic exposures as well as some methodological approaches will be discussed and tested by using the data of the Czech and French cohorts. These two cohorts present annual exposures varying by a factor of 5 to 10, French exposure rates being close or even less than 0.1 Working Level during the last 20 years. The project is integrated in a larger European project on uranium miners, co-ordinated by IPSN. (author)

  11. Accidental fire in the West Hall

    1977-01-01

    On January 7 an accidental fire due to the failure of standard circuit-breakers, destroyed the coils of two spectrometer magnets and severely damaged the apparatus of two experiments. See also photos 7701582X, 7701581X, 7701580X. (Annual Report 1977, pg. 127-128)

  12. Medical handling of accidentally exposed individuals: recommendations

    The manual Medical Handling of Accidentally Exposed Individual, IAEA Safety Series no. 88 has been translated to portuguese language. Additional considerations about the Goiania radiological accident were incorporated to the original text, which provides knowledge involving health problems to both workers and public members. Also information concerning blood, recent radiological accidents, recommended maximum limited doses and a glossary were introduced. 5 refs

  13. Gestational and Chronic Low-Dose PFOA Exposures and Mammary Gland Growth and Differentiation in Three Generations of CD-1 Mice

    White, Sally S.; Stanko, Jason P.; Kato, Kayoko; Calafat, Antonia M.; Hines, Erin P.; Fenton, Suzanne E.

    2011-01-01

    Background: Prenatal exposure to perfluorooctanoic acid (PFOA), a ubiquitous industrial surfactant, has been reported to delay mammary gland development in female mouse offspring (F1) and the treated lactating dam (P0) after gestational treatments at 3 and 5 mg PFOA/kg/day. Objective: We investigated the consequences of gestational and chronic PFOA exposure on F1 lactational function and subsequent development of F2 offspring. Methods: We treated P0 dams with 0, 1, or 5 mg PFOA/kg/day on gest...

  14. Cumulative and current exposure to potentially nephrotoxic antiretrovirals and development of chronic kidney disease in HIV-positive individuals with a normal baseline estimated glomerular filtration rate

    Mocroft, Amanda; Lundgren, Jens D; Ross, Michael;

    2016-01-01

    with cumulative exposure to tenofovir disoproxil fumarate, ritonavir-boosted atazanavir, ritonavir-boosted lopinavir, other ritonavir-boosted protease inhibitors, or abacavir. FINDINGS: Between Jan 1, 2004, and July 26, 2013, 23,905 eligible individuals from the D:A:D study were included. Participants...... (1·20 [1·13-1·26], p<0·0001), and ritonavir-boosted lopinavir (1·11 [1·06-1·16], p<0·0001), but not other ritonavir-boosted protease inhibitors or abacavir. INTERPRETATION: In people with normal renal function, the annual incidence of chronic kidney disease increased for up to 6 years of exposure to...

  15. Behavioral effects of D3 receptor inhibition and 5-HT4 receptor activation on animals undergoing chronic cannabinoid exposure during adolescence.

    Abboussi, Oualid; Said, Nadia; Fifel, Karim; Lakehayli, Sara; Tazi, Abdelouahhab; El Ganouni, Soumaya

    2016-04-01

    Chronic exposure to cannabinoids during adolescence results in long-lasting behavioral deficits that match some symptomatologic aspects of schizophrenia. The aim of this study was to investigate the reversibility of the emotional and the cognitive effects of chronic exposure to cannabinoids during adolescence, via subsequent modulation of the serotoninergic 5-HT4 and dopaminergic D3 receptors. RS67333 as a 5-HT4 agonist and U-99194A as a D3 antagonist were administered separately at 1 mg/kg and 20 mg/kg, and in combination at 0.5 mg/kg and 10 mg/kg to adult animals undergoing chronic treatment with the synthetic cannabinoid receptor agonist WIN55,212-2 (1 mg/kg) during adolescence. Animals were tested for anxiety-like behavior and episodic-like memory in the open field and novel object recognition tests respectively 30 minutes after the last drug administration. Chronic WIN55,212-2 treated animals exhibited a lasting disruption of episodic memory and increased anxiety levels. The effect on episodic-like memory were partially restored by acute administration of RS67333 and U-99194A and completely by administration of both drugs in combination at lower doses. However, only RS67333 (20 mg/kg) improved the anxiogenic-like effect of WIN55,212-2. These findings give further support that chronic exposure to cannabinoids during adolescence may be used as an animal model for schizophrenia, and highlight D3 and 5-HT4 receptors as potential targets for an enhanced treatment of the cognitive aspect of this disease. PMID:26497809

  16. Hippocampal cytogenesis and spatial learning in senile rats exposed to chronic variable stress: effects of previous early life exposure to mild stress

    Fernando Jauregui-Huerta

    2015-08-01

    Full Text Available In this study, we exposed adult rats to chronic variable stress and tested the hypothesis that previous early-life exposure to stress changes the manner in which older subjects respond to aversive conditions. To this end, we analyzed the cytogenic changes in the hippocampus and hippocampal-dependent spatial learning performance. The experiments were performed on 18-month-old male rats divided into 4 groups as follows: Control (old rats under standard laboratory conditions, Early-life stress (old rats who were exposed to environmental noise from postnatal days 21 to 35, Chronic variable stress + Early-life stress (old rats exposed to a chronic stress protocol who were previously exposed to the early-life noise stress and Chronic variable stress (old rats who were exposed only to the chronic stress protocol. The Morris Water Maze (MWM was employed to evaluate the spatial learning abilities of the rats at the end of the experiment. Immunohistochemistry against 5’Bromodeoxiuridine (BrdU and glial fibrillar acidic protein (GFAP was also conducted in the DG, CA1, CA2 and CA3 regions of the hippocampus. We confocally analyzed the cytogenic (BrdU-labeled cells and astrogenic (BrdU+GFAP-labeled cells changes produced by these conditions. Using this procedure, we found that stress diminished the total number of BrdU+ cells over the main proliferative area of the hippocampus (i.e., the dentate gyrus but increased the astrocyte phenotypes (GFAP+BrdU. The depleted BrdU+ cells were restored when the senile rats also experienced stress at the early stages of life. The MWM assessment demonstrated that stress also impairs the ability of the rats to learn the task. This impairment was not present when the stressful experience was preceded by the early-life exposure. Thus, our results support the idea that previous exposure to mild stressing agents may have beneficial effects on aged subjects.

  17. Comparing the Efficacy of Eye Movement Desensitization and Reprocessing Therapy with Prolonged Exposure Therapy on the Trauma impact symptoms in Veterans Suffering from Chronic PTSD

    A Maredpour; F. Naderi; M Mehrabizadeh-Honarmand

    2013-01-01

    Abstract Background and aim: Post-traumatic stress disorder is considered as set of symptoms developed afterward an individual witness, hear or involved. The current research was purposed to compare the efficacy of eye movement desensitization and reprocessing therapy with prolonged exposure therapy on the trauma impact symptoms in veterans suffering from chronic PTSD. Methods: in this clinical trail research randomly sampled 48 veterans diagnosed with PTSD who had psychiatric rec...

  18. The treatment of fear of movement/ (re)injury in chronic low back pain: further evidence on the effectiveness of exposure in vivo

    Vlaeyen, Johannes; de Jong, Jeroen; Geilen, Mario; Heuts, Peter H. T. G.; Breukelen, Gerard

    2002-01-01

    BACKGROUND AND OBJECTIVE: Several cognitive-behavioral factors contribute to the persistence of pain disability in patients with chronic back pain. Fear-avoidance beliefs and fear of movement/(re)injury in particular have been shown to be strong predictors of physical performance and pain disability. Patients reporting substantial pain-related fear might benefit from exposure in vivo to a set of individually tailored, fear-eliciting, and hierarchically ordered physical movements rather than m...

  19. A Factor Analysis of Global GABAergic Gene Expression in Human Brain Identifies Specificity in Response to Chronic Alcohol and Cocaine Exposure

    Enoch, Mary-Anne; Baghal, Basel; Yuan, Qiaoping; Goldman, David

    2013-01-01

    Although expression patterns of GABAergic genes in rodent brain have largely been elucidated, no comprehensive studies have been performed in human brain. The purpose of this study was to identify global patterns of GABAergic gene expression in healthy adults, including trans and cis effects in the GABAA gene clusters, before determining the effects of chronic alcohol and cocaine exposure on gene expression in the hippocampus. RNA-Seq data from ‘BrainSpan’ was obtained across 16 brain regions...

  20. Effects of prenatal exposure to a mild chronic variable stress on body weight, preweaning mortality and rat behavior

    Cabrera R.J.

    1999-01-01

    Full Text Available Early stimulation has been shown to produce long-lasting effects in many species. Prenatal exposure to some strong stressors may affect development of the nervous system leading to behavioral impairment in adult life. The purpose of the present work was to study the postnatal harmful effects of exposure to variable mild stresses in rats during pregnancy. Female Holtzman rats were submitted daily to one session of a chronic variable stress (CVS during pregnancy (prenatal stress; PS group. Control pregnant rats (C group were undisturbed. The pups of PS and C dams were weighed and separated into two groups 48 h after delivery. One group was maintained with their own dams (PS group, N = 70; C group, N = 36 while the other PS pups were cross-fostered with C dams (PSF group, N = 47 and the other C pups were cross-fostered with PS dams (CF group, N = 58. Pups were undisturbed until weaning (postnatal day 28. The male offspring underwent motor activity tests (day 28, enriched environment tests (day 37 and social interaction tests (day 42 in an animal activity monitor. Body weight was recorded on days 2, 28 and 60. The PS pups showed lower birth weight than C pups (Duncan's test, P<0.05. The PS pups suckling with their stressed mothers displayed greater preweaning mortality (C: 23%, PS: 60%; c2 test, P<0.05 and lower body weight than controls at days 28 and 60 (Duncan's test, P<0.05 and P<0.01, respectively. The PS, PSF and CF groups showed lower motor activity scores than controls when tested at day 28 (Duncan's test, P<0.01 for PS group and P<0.05 for CF and PSF groups. In the enriched environment test performed on day 37, between-group differences in total motor activity were not detected; however, the PS, CF and PSF groups displayed less exploration time than controls (Duncan's test, P<0.05. Only the PS group showed impaired motor activity and impaired social behavior at day 42 (Duncan's test, P<0.05. In fact, CVS treatment during gestation plus

  1. Evidence for oxidative stress in the developing cerebellum of the rat after chronic mild carbon monoxide exposure (0.0025% in air

    Lopez Ivan A

    2009-05-01

    Full Text Available Abstract Background The present study was designed to test the hypothesis that chronic very mild prenatal carbon monoxide (CO exposure (25 parts per million subverts the normal development of the rat cerebellar cortex. Studies at this chronic low CO exposure over the earliest periods of mammalian development have not been performed to date. Pregnant rats were exposed chronically to CO from gestational day E5 to E20. In the postnatal period, rat pups were grouped as follows: Group A: prenatal exposure to CO only; group B: prenatal exposure to CO then exposed to CO from postnatal day 5 (P5 to P20; group C: postnatal exposure only, from P5 to P20, and group D, controls (air without CO. At P20, immunocytochemical analyses of oxidative stress markers, and structural and functional proteins were assessed in the cerebellar cortex of the four groups. Quantitative real time PCR assays were performed for inducible (iNOS, neuronal (nNOS, and endothelial (eNOS nitric oxide synthases. Results Superoxide dismutase-1 (SOD1, SOD2, and hemeoxygenase-1 (HO-1 immunoreactivity increased in cells of the cerebellar cortex of CO-exposed pups. INOS and nitrotyrosine immunoreactivity also increased in blood vessels and Purkinje cells (PCs of pups from group-A, B and C. By contrast, nNOS immunoreactivity decreased in PCs from group-B. Endothelial NOS immunoreactivity showed no changes in any CO-exposed group. The mRNA levels for iNOS were significantly up-regulated in the cerebellum of rats from group B; however, mRNA levels for nNOS and eNOS remained relatively unchanged in groups A, B and C. Ferritin-H immunoreactivity increased in group-B. Immunocytochemistry for neurofilaments (structural protein, synapsin-1 (functional protein, and glutamic acid decarboxylase (the enzyme responsible for the synthesis of the inhibitory neurotransmitter GABA, were decreased in groups A and B. Immunoreactivity for two calcium binding proteins, parvalbumin and calbindin, remained

  2. An incident study about acute and chronic human exposure to uranium by high-resolution inductively coupled plasma mass spectrometry (HR-ICPMS).

    Krystek, Petra; Ritsema, Rob

    2009-01-01

    From the year 2003 to 2005 around 1700 Dutch soldiers made a part of the international stabilisation force in Iraq. An incident happened as a group of four Dutch soldiers found a 30mm bullet identified as containing depleted uranium (DU). The main pathway of the acute exposure is via inhalation of small uranium containing particles, e.g. from a bullet during its explosion. To develop a method for acute exposure investigations were carried out about finding an efficient and suitable way to sample nasal mucus as medium of inhalation. Generally, in human exposure studies with regard to natural uranium (NU) or DU, urine is the matrix for analysis. Uranium concentrations in urine are based on daily ingestion depending on the composition of drinking water and food. A second possibility is the acute exposure to uranium after an incident, either through inhalation or impact. Nevertheless, the results deliver only interpretations in respect to chronic/long-term exposure. For the acute exposure procedures like sniffling out into cleansing tissues and rinsing the nose were tested with real-life samples from four soldiers involved in an incident with possibly acute exposure to uranium. For the quantification of uranium high-resolution inductively coupled plasma mass spectrometry (HR-ICPMS) was applied. PMID:18187363

  3. Chronic glucocorticoid exposure-induced epididymal adiposity is associated with mitochondrial dysfunction in white adipose tissue of male C57BL/6J mice.

    Jie Yu

    Full Text Available Prolonged and excessive glucocorticoids (GC exposure resulted from Cushing's syndrome or GC therapy develops central obesity. Moreover, mitochondria are crucial in adipose energy homeostasis. Thus, we tested the hypothesis that mitochondrial dysfunction may contribute to chronic GC exposure-induced epididymal adiposity in the present study. A total of thirty-six 5-week-old male C57BL/6J mice (∼20 g were administrated with 100 µg/ml corticosterone (CORT or vehicle through drinking water for 4 weeks. Chronic CORT exposure mildly decreased body weight without altering food and water intake in mice. The epididymal fat accumulation was increased, but adipocyte size was decreased by CORT. CORT also increased plasma CORT, insulin, leptin, and fibroblast growth factor 21 concentrations as measured by RIA or ELISA. Interestingly, CORT increased plasma levels of triacylglycerols and nonesterified fatty acids, and up-regulated the expression of both lipolytic and lipogenic genes as determined by real-time RT-PCR. Furthermore, CORT impaired mitochondrial biogenesis and oxidative function in epididymal WAT. The reactive oxygen species production was increased and the activities of anti-oxidative enzymes were reduced by CORT treatment as well. Taken together, these findings reveal that chronic CORT administration-induced epididymal adiposity is, at least in part, associated with mitochondrial dysfunction in mouse epididymal white adipose tissue.

  4. Chronic carbon monoxide exposure is associated with the increases in carotid intima-media thickness and C-reactive protein level.

    Davutoglu, Vedat; Zengin, Suat; Sari, Ibrahim; Yildirim, Cuma; Al, Behcet; Yuce, Murat; Ercan, Suleyman

    2009-11-01

    Being the most common cause of death from poisoning worldwide, cardiovascular manifestations of acute carbon monoxide (CO) poisoning have been subject of various studies but current evidence about effects of chronic CO exposure on atherosclerosis is limited which is very common. We aimed to investigate association of chronic CO exposure with atherosclerosis by measuring carotid intima-media thickness (CIMT) and high-sensitivity C-reactive protein (hs-CRP). Forty healthy male non-smoker indoor barbecue workers (mean age; 33.0 +/- 9.0 years) working in different restaurants for at least three years and 48 age-matched healthy men (mean age; 34.3 +/- 6.6 years) enrolled in the study. Clinical characteristics of indoor barbecue workers and control group were comparable in terms of body mass index, blood pressure, and lipid profile. However, carboxyhemoglobin (COHb) (6.4 +/- 1.5% vs. 2.0 +/- 1.1%), hs-CRP (2.7 +/- 2.0 mg/L vs. 1.1 +/- 0.8 mg/L) and CIMT (1.1 +/- 0.3 mm vs. 0.9 +/- 0.1 mm) were higher in indoor barbecue workers (p independent predictor of CIMT (beta = 0.571, p < 0.001). The increased CIMT and hs-CRP in indoor barbecue workers suggest that chronic CO exposure may increase the risk of atherosclerotic cardiovascular events. PMID:19851048

  5. Report of an accidental exposure of patients in radiation therapy

    Full text. Accident with radiation therapy patients, when they happen, have a high probability of being very severe. This paper reports an accident that occurred last November in Brazil involving several patients submitted to therapy with clinical electron beams from 6 to 12 MeV. A field response team from the Instituto de Radioprotecao e Dosimetria (IRD), and the Laboratorio de Ciencias Radiologicas (LCR/DBB/UERJ), was sent to identify the causes of the accident and evaluate its consequences. The report suggests several actions to be observed by regulatory authorities, licensees and several other legal persons and individuals with subsidiary responsibilities. Evaluation of radiologic accidents is important because it permits to introduce the lessons learned in the radiation protection system, including design of equipment and installations, radiation procedures and personnel qualification and because it renders and attitude of continuous alert so a non usual event will not run into an accident. The accident A 'flat/sym'interlock problem occurred with the electron beam of a Mevatron-74 linear accelerator. After consulting the physicist, the technicians operated the equipment on the 'research mode' (non-clinical). Later the physicist came to verify the equipment and noticed that the dose rate presented high oscillation and that the 'pgm/norm'key was set to 'pgm'. After setting the control to 'norm'the equipment resumed working and some patients were treated in clinical mode and some in research mode. The machine then stops working and the service personnel were called. On 11/28 the maintenance technician fixed the equipment and the physicist measured the dose rate under 'pgm'mode and notice that it was about eight times over the normal value. COnclusion: the working group concluded that the accident could happen only if the equipment were operated on non-clinical mode. It can be summarized as : The event initiator: the flat/sym interlock. The accident promoter: the equipment was operated on non-clinical mode. A non-usual event was the 'pgm/norm' key that was set wrongly to 'pgm' contributed to the fate. The extent: during the accident the electron beams corresponded in intensity and energy to those used to photon generation. The dosimetry reconstitution showed doses 8 to 9 times over the prescription. A patient was treated on 11/26 and eight on 11/27 on research mode with dose ranging from 1400 to 2000 cGy, depending on the prescription. The patients presented dry and/or humid scamation with further clinical regression

  6. Chronic exposure to triclosan sustains microbial community shifts and alters antibiotic resistance gene levels in anaerobic digesters.

    Carey, Daniel E; Zitomer, Daniel H; Kappell, Anthony D; Choi, Melinda J; Hristova, Krassimira R; McNamara, Patrick J

    2016-08-10

    Triclosan, an antimicrobial chemical found in consumer personal care products, has been shown to stimulate antibiotic resistance in pathogenic bacteria. Although many studies focus on antibiotic resistance pertinent to medical scenarios, resistance developed in natural and engineered environments is less studied and has become an emerging concern for human health. In this study, the impacts of chronic triclosan (TCS) exposure on antibiotic resistance genes (ARGs) and microbial community structure were assessed in lab-scale anaerobic digesters. TCS concentrations from below detection to 2500 mg kg(-1) dry solids were amended into anaerobic digesters over 110 days and acclimated for >3 solid retention time values. Four steady state TCS concentrations were chosen (30-2500 mg kg(-1)). Relative abundance of mexB, a gene coding for a component of a multidrug efflux pump, was significantly higher in all TCS-amended digesters (30 mg kg(-1) or higher) relative to the control. TCS selected for bacteria carrying tet(L) and against those carrying erm(F) at concentrations which inhibited digester function; the pH decrease associated with digester failure was suspected to cause this selection. Little to no impact of TCS was observed on intI1 relative abundance. Microbial communities were also surveyed by high-throughput 16S rRNA gene sequencing. Compared to the control digesters, significant shifts in community structure towards clades containing commensal and pathogenic bacteria were observed in digesters containing TCS. Based on these results, TCS should be included in studies and risk assessments that attempt to elucidate relationships between chemical stressors (e.g. antibiotics), antibiotic resistance genes, and public health. PMID:27291499

  7. The Efficacy of Syzygium aromaticum Essential Oil in Cognitive Disorders against Manganese Chronic Exposure in Rats during Development

    Djallal Eddine Houari ADLI

    2014-06-01

    Full Text Available The essential oil of Syzygium aromaticum has been widely used in traditional medicine to treat a variety of diseases, including some neurological disorders. This study aims at testing, in vivo, the possible anxiolytic and antidepressant effects, of the Syzygium aromaticum essential oil against chronic manganese chloride (4.79 mg/l intoxication during the gestation and lactation period, in Wistar rat pups. Wistar rat pups were exposed to manganese via their dams’ drinking water from postnatal day (PND 1 to (PND 21. After their weaning, the rats exposed to manganese received injections of essential oil of Syzygium aromaticum (0.1 ml/kg for 18 days. The level of anxiety, depression and locomotor activity were studied. Locomotor activity (open field test, anxiety (elevated plus maze tests, and depression (forced swimming test were evaluated. The results of the present study indicate that Manganese exposure induces, on the one hand, impairments of body (p<0.001 and of brain weight (p<0.05. On the other hand, it increases level of anxiety (p<0.05, depression (p<0.001 and locomotor hyporactivity (p<0.001, when compared to control rats. Administration of essential oil of Syzygium aromaticum leads to a reduction in the level of anxiety (p<0.05, of depression (p<0.001 and corrects locomotor hyporactivity (p<0.05 in rats exposed to manganese beforehand. These results suggest that essential oil of Syzygium aromaticum can employ as a natural, protective agent against neuro-toxicity induced by manganese chloride during the gestation and lactation periods.

  8. The effect of World Trade Center exposure on the latency of chronic rhinosinusitis diagnoses in New York City firefighters: 2001–2011

    Weakley, Jessica; Hall, Charles B; Liu, Xiaoxue; Zeig-Owens, Rachel; Webber, Mayris P; Schwartz, Theresa; Prezant, David

    2016-01-01

    Objective To assess how the effect of World Trade Center (WTC) exposure on physician-diagnosed chronic rhinosinusitis (CRS) in firefighters changed during the decade following the attack on 9/11 (11 September 2001 to 10 September 2011). Methods We examined temporal effects on the relation between WTC exposure and the incidence of physician diagnosed CRS in firefighters changed during the decade following the attack on 9/11 (11 September 2001 to 10 September 2011). Exposure was grouped by time of arrival at the WTC site as follows: (high) morning 11 September 2001 (n=1623); (moderate) afternoon 11 September 2001 or 12 September 2001 (n=7025); or (low) 13–24 September 2001 (n=1200). Piecewise exponential survival models were used to estimate incidences by exposure group, with change points in the relative incidences estimated by maximum likelihood. Results Incidences dramatically increased after 2007 due to a programmatic change that provided free medical treatment, but increases were similar in all exposure groups. For this reason, we observed no change point during the study period, meaning the relative incidence by exposure group (high vs moderate vs low) of CRS disease did not significantly change over the study period. The relative rate of developing CRS was 1.99 (95% CI=1.64 to 2.41) for high versus low exposure, and 1.52 (95% CI=1.28 to 1.80) for moderate versus low exposure during the 10-year follow-up period. Conclusions The risk of CRS in FDNY firefighters appears increased with WTC-exposure, and has not diminished by time since exposure. PMID:26574577

  9. Cellular impact of combinations of endosulfan, atrazine, and chlorpyrifos on human primary hepatocytes and HepaRG cells after short and chronic exposures.

    Nawaz, Ahmad; Razpotnik, Andrej; Rouimi, Patrick; de Sousa, Georges; Cravedi, Jean Pierre; Rahmani, Roger

    2014-02-01

    Chronic exposure to low doses of pesticides present in the environment is increasingly suspected to cause major health issues to humans. Toxicological evaluations become more complex when the exposure concerns chemical combinations. Atrazine, chlorpyrifos, and endosulfan are pesticides used worldwide in agriculture and are therefore currently found at residual levels in food and the environment, even in countries in which they are now banned. Our study aimed to use Real-Time Cell Impedance Analyzer to investigate changes in phenotypical status of primary human hepatocytes and differentiated HepaRG cells induced by short and chronic exposures to these three chemicals. In contrast to the traditionally used endpoint cytotoxicity test, this technology allows kinetic measurements in real-time throughout the entire experiment. Our data show significantly higher cytotoxic effects of mixtures as compared to individual pesticides and a greater susceptibility of human hepatocytes as compared to HepaRG to short-term exposure (24 h). Repeated exposure over 2 weeks to endosulfan and endosulfan-containing mixture induced HepaRG cell death in a time- and dose-dependent manner. Of the typical genes involved in metabolism and cell-response to xenobiotics, we found an exposure time- and condition-dependent deregulation of the expression of CYP3A4 and UGT1A in HepaRG cells exposed to low doses of pesticides and mixtures. Our data demonstrate the usefulness of real-time cell monitoring in long-term toxicological evaluations of co-exposure to xenobiotics. In addition, they support but at the same time highlight certain limitations in the use of HepaRG cells as the gold standard liver cell model in toxicity studies. PMID:24343343

  10. Interest of stable iodine prophylaxis in accidental situation

    In the case of an accident on a nuclear reactor, radioactive substances could be released in atmosphere. among these substances, the presence of radioactive isotopes of iodine is a constant, that, in the lack of efficient counter measures could lead to an internal contamination, principally by inhalation but also by contaminated food ingestion. The radioactive iodine accumulate in the thyroid, leading to an exposure that at term can induce an increase of a cancer risk for this gland among the most sensitive persons, especially the children. It exists a simple and efficient protection mean: the taking of a tablet of stable iodine. In this article, the interest of the prophylaxis by stable iodine in accidental situation is tackled under the shape of eleven independent questions/answers, allowing a reading in several times but also the research of response elements to a question that the reader could wonder. (N.C.)

  11. Human circulating plasma DNA significantly decreases while lymphocyte DNA damage increases under chronic occupational exposure to low-dose gamma-neutron and tritium β-radiation

    Korzeneva, Inna B., E-mail: inna.korzeneva@molgen.vniief.ru [Russian Federal Nuclear Center – All-Russian Research Institute of Experimental Physics (RFNC-VNIIEF) 607190, Sarov, 37 Mira ave., Nizhniy Novgorod Region (Russian Federation); Kostuyk, Svetlana V.; Ershova, Liza S. [Research Centre for Medical Genetics, Russian Academy of Medical Sciences, 115478 Moscow, 1 Moskvorechye str. (Russian Federation); Osipov, Andrian N. [Federal Medial and Biological Center named after Burnazyan of the Federal Medical and Biological Agency (FMBTz named after Burnazyan of FMBA), Moscow (Russian Federation); State Research Center - Burnasyan Federal Medical Biophysical Center of Federal Medical Biological Agency, Zhivopisnaya, 46, Moscow, 123098 (Russian Federation); Zhuravleva, Veronika F.; Pankratova, Galina V. [Russian Federal Nuclear Center – All-Russian Research Institute of Experimental Physics (RFNC-VNIIEF) 607190, Sarov, 37 Mira ave., Nizhniy Novgorod Region (Russian Federation); Porokhovnik, Lev N.; Veiko, Natalia N. [Research Centre for Medical Genetics, Russian Academy of Medical Sciences, 115478 Moscow, 1 Moskvorechye str. (Russian Federation)

    2015-09-15

    Highlights: • The chronic exposure to low-dose IR induces DSBs in human lymphocytes (TM index). • Exposure to IR decreases the level of human circulating DNA (cfDNA index). • IR induces an increase of DNase1 activity (DNase1 index) in plasma. • IR induces an increase of the level of antibodies to DNA (Ab DNA index) in plasma. • The ratio cfDNA/(DNase 1 × Ab DNA × TM) is a potential marker of human exposure to IR. - Abstract: The blood plasma of healthy people contains cell-fee (circulating) DNA (cfDNA). Apoptotic cells are the main source of the cfDNA. The cfDNA concentration increases in case of the organism’s cell death rate increase, for example in case of exposure to high-dose ionizing radiation (IR). The objects of the present research are the blood plasma and blood lymphocytes of people, who contacted occupationally with the sources of external gamma/neutron radiation or internal β-radiation of tritium N = 176). As the controls (references), blood samples of people, who had never been occupationally subjected to the IR sources, were used (N = 109). With respect to the plasma samples of each donor there were defined: the cfDNA concentration (the cfDNA index), DNase1 activity (the DNase1 index) and titre of antibodies to DNA (the Ab DNA index). The general DNA damage in the cells was defined (using the Comet assay, the tail moment (TM) index). A chronic effect of the low-dose ionizing radiation on a human being is accompanied by the enhancement of the DNA damage in lymphocytes along with a considerable cfDNA content reduction, while the DNase1 content and concentration of antibodies to DNA (Ab DNA) increase. All the aforementioned changes were also observed in people, who had not worked with the IR sources for more than a year. The ratio cfDNA/(DNase1 × Ab DNA × TM) is proposed to be used as a marker of the chronic exposure of a person to the external low-dose IR. It was formulated the assumption that the joint analysis of the cfDNA, DNase1, Ab

  12. Human circulating plasma DNA significantly decreases while lymphocyte DNA damage increases under chronic occupational exposure to low-dose gamma-neutron and tritium β-radiation

    Highlights: • The chronic exposure to low-dose IR induces DSBs in human lymphocytes (TM index). • Exposure to IR decreases the level of human circulating DNA (cfDNA index). • IR induces an increase of DNase1 activity (DNase1 index) in plasma. • IR induces an increase of the level of antibodies to DNA (Ab DNA index) in plasma. • The ratio cfDNA/(DNase 1 × Ab DNA × TM) is a potential marker of human exposure to IR. - Abstract: The blood plasma of healthy people contains cell-fee (circulating) DNA (cfDNA). Apoptotic cells are the main source of the cfDNA. The cfDNA concentration increases in case of the organism’s cell death rate increase, for example in case of exposure to high-dose ionizing radiation (IR). The objects of the present research are the blood plasma and blood lymphocytes of people, who contacted occupationally with the sources of external gamma/neutron radiation or internal β-radiation of tritium N = 176). As the controls (references), blood samples of people, who had never been occupationally subjected to the IR sources, were used (N = 109). With respect to the plasma samples of each donor there were defined: the cfDNA concentration (the cfDNA index), DNase1 activity (the DNase1 index) and titre of antibodies to DNA (the Ab DNA index). The general DNA damage in the cells was defined (using the Comet assay, the tail moment (TM) index). A chronic effect of the low-dose ionizing radiation on a human being is accompanied by the enhancement of the DNA damage in lymphocytes along with a considerable cfDNA content reduction, while the DNase1 content and concentration of antibodies to DNA (Ab DNA) increase. All the aforementioned changes were also observed in people, who had not worked with the IR sources for more than a year. The ratio cfDNA/(DNase1 × Ab DNA × TM) is proposed to be used as a marker of the chronic exposure of a person to the external low-dose IR. It was formulated the assumption that the joint analysis of the cfDNA, DNase1, Ab

  13. Anaphylaxis after accidental ingestion of kiwi fruit

    Gawrońska-Ukleja, Ewa; Różalska, Anna; Ukleja-Sokołowska, Natalia; Żbikowska-Gotz, Magdalena; Bartuzi, Zbigniew

    2013-01-01

    Numerous cases of anaphylaxis after ingestion of kiwi fruit, after the skin tests and during oral immunotherapy were described. The article describes the case of severe anaphylactic reaction that occurred in a 55-year-old patient after accidental ingestion of kiwi. Allergy to kiwi fruit was confirmed by a native test with fresh kiwi fruit. After the test, the patient experienced generalized organ response in the form of headache, general weakness and rashes on the neck and breast, and dyspnea...

  14. Accidental swallowing of orthodontic expansion appliance key.

    Monini, André da Costa; Maia, Luiz Guilherme Martins; Jacob, Helder Baldi; Gandini, Luiz Gonzaga

    2011-08-01

    Ingestion of a foreign object, including a dental object, can lead to a trip to the emergency room. This article describes the accidental swallowing of a key that was used to activate a rapid maxillary expander. An orthodontic patient swallowed the key while trying to activate the appliance at home. The object's trajectory was followed on radiographs until it was eliminated. Possible clinical complications, legal implications of this situation, and practices for prevention are described. PMID:21803265

  15. The Putative Role of Viruses, Bacteria, and Chronic Fungal Biotoxin Exposure in the Genesis of Intractable Fatigue Accompanied by Cognitive and Physical Disability.

    Morris, Gerwyn; Berk, Michael; Walder, Ken; Maes, Michael

    2016-05-01

    Patients who present with severe intractable apparently idiopathic fatigue accompanied by profound physical and or cognitive disability present a significant therapeutic challenge. The effect of psychological counseling is limited, with significant but very slight improvements in psychometric measures of fatigue and disability but no improvement on scientific measures of physical impairment compared to controls. Similarly, exercise regimes either produce significant, but practically unimportant, benefit or provoke symptom exacerbation. Many such patients are afforded the exclusionary, non-specific diagnosis of chronic fatigue syndrome if rudimentary testing fails to discover the cause of their symptoms. More sophisticated investigations often reveal the presence of a range of pathogens capable of establishing life-long infections with sophisticated immune evasion strategies, including Parvoviruses, HHV6, variants of Epstein-Barr, Cytomegalovirus, Mycoplasma, and Borrelia burgdorferi. Other patients have a history of chronic fungal or other biotoxin exposure. Herein, we explain the epigenetic factors that may render such individuals susceptible to the chronic pathology induced by such agents, how such agents induce pathology, and, indeed, how such pathology can persist and even amplify even when infections have cleared or when biotoxin exposure has ceased. The presence of active, reactivated, or even latent Herpes virus could be a potential source of intractable fatigue accompanied by profound physical and or cognitive disability in some patients, and the same may be true of persistent Parvovirus B12 and mycoplasma infection. A history of chronic mold exposure is a feasible explanation for such symptoms, as is the presence of B. burgdorferi. The complex tropism, life cycles, genetic variability, and low titer of many of these pathogens makes their detection in blood a challenge. Examination of lymphoid tissue or CSF in such circumstances may be warranted. PMID

  16. Early Life Exposure to Chronic Intermittent Hypoxia Primes Increased Susceptibility to Hypoxia-Induced Weakness in Rat Sternohyoid Muscle During Adulthood

    Fiona B Mcdonald

    2016-03-01

    Full Text Available Intermittent hypoxia is a feature of apnea of prematurity, chronic lung disease and sleep apnea. Despite the clinical relevance, the long-term effects of hypoxic exposure in early life on respiratory control are not well defined. We recently reported that exposure to chronic intermittent hypoxia (CIH during postnatal development (pCIH causes upper airway muscle weakness in both sexes, which persists for several weeks. We sought to examine if there are persistent sex-dependent effects of pCIH on respiratory muscle function into adulthood and/or increased susceptibility to re-exposure to CIH in adulthood in animals previously exposed to CIH during postnatal development. We hypothesized that pCIH would cause long-lasting muscle impairment and increased susceptibility to subsequent hypoxia. Within 24 hours of delivery, pups and their respective dams were exposed to CIH: 90s of hypoxia reaching 5% O2 at nadir; once every 5 min, 8 hrs per day for 3 weeks. Sham groups were exposed to normoxia in parallel. Three groups were studied: sham; pCIH; and pCIH combined with adult CIH (p+aCIH, where a subset of the pCIH-exposed pups were re-exposed to the same CIH paradigm beginning at 13 weeks. Following gas exposures, sternohyoid and diaphragm muscle isometric contractile and endurance properties were examined ex vivo. There was no apparent lasting effect of pCIH on respiratory muscle function in adults. However, in both males and females, re-exposure to CIH in adulthood in pCIH-exposed animals caused sternohyoid (but not diaphragm weakness. Exposure to this paradigm of CIH in adulthood alone had no effect on muscle function. Persistent susceptibility in pCIH-exposed airway dilator muscle to subsequent hypoxic insult may have implications for the control of airway patency in adult humans exposed to intermittent hypoxic stress during early life.

  17. CHRONIC EXPOSURE TO DIBROMOACETIC ACID, A WATER DISINFECTION BY-PRODUCT, DIMINISHES PRIMORDIAL FOLLICLES IN THE RABBIT

    Exposure to dibromoacetic acid (DBA), a commonly occurring water disinfection by-product, has detrimental effects on spermatogenesis and fertility in rats and rabbits. Despite indications of important reproductive consequences of DBA exposure in males, reproductive sequelae follo...

  18. Ex vivo exposure of bone marrow from chronic kidney disease donor rats to pravastatin limits renal damage in recipient rats with chronic kidney disease

    Koppen, A. van; Papazova, D.A.; Oosterhuis, N.R.; Gremmels, H.; Giles, R.H.; Fledderus, J.O.; Joles, J.A.; Verhaar, M.C.

    2015-01-01

    Introduction: Healthy bone marrow cell (BMC) infusion improves renal function and limits renal injury in a model of chronic kidney disease (CKD) in rats. However, BMCs derived from rats with CKD fail to retain beneficial effects, demonstrating limited therapeutic efficacy. Statins have been reported

  19. Chronic Intermittent Ethanol Exposure Enhances the Excitability and Synaptic Plasticity of Lateral Orbitofrontal Cortex Neurons and Induces a Tolerance to the Acute Inhibitory Actions of Ethanol.

    Nimitvilai, Sudarat; Lopez, Marcelo F; Mulholland, Patrick J; Woodward, John J

    2016-03-01

    Alcoholism is associated with changes in brain reward and control systems, including the prefrontal cortex. In prefrontal areas, the orbitofrontal cortex (OFC) has been suggested to have an important role in the development of alcohol-abuse disorders and studies from this laboratory demonstrate that OFC-mediated behaviors are impaired in alcohol-dependent animals. However, it is not known whether chronic alcohol (ethanol) exposure alters the fundamental properties of OFC neurons. In this study, mice were exposed to repeated cycles of chronic intermittent ethanol (CIE) exposure to induce dependence and whole-cell patch-clamp electrophysiology was used to examine the effects of CIE treatment on lateral OFC (lOFC) neuron excitability, synaptic transmission, and plasticity. Repeated cycles of CIE exposure and withdrawal enhanced current-evoked action potential (AP) spiking and this was accompanied by a reduction in the after-hyperpolarization and a decrease in the functional activity of SK channels. CIE mice also showed an increase in the AMPA/NMDA ratio, and this was associated with an increase in GluA1/GluA2 AMPA receptor expression and a decrease in GluN2B NMDA receptor subunits. Following CIE treatment, lOFC neurons displayed a persistent long-term potentiation of glutamatergic synaptic transmission following a spike-timing-dependent protocol. Lastly, CIE treatment diminished the inhibitory effect of acute ethanol on AP spiking of lOFC neurons and reduced expression of the GlyT1 transporter. Taken together, these results suggest that chronic exposure to ethanol leads to enhanced intrinsic excitability and glutamatergic synaptic signaling of lOFC neurons. These alterations may contribute to the impairment of OFC-dependent behaviors in alcohol-dependent individuals. PMID:26286839

  20. Quantification of years of life lost attributable to chronic air pollution exposure in a health impact assessment: the case of Nantes

    Background: When French regional planning for air quality first began, exposure-response functions from time-series studies were used to assess the short-term health impact of urban air pollution. The World Health Organisation also suggests that exposure-response functions from cohort studies be taken into account to evaluate the effects of chronic exposure and to quantify the prematurity of deaths related to chronic exposure to air pollution. This work characterizes the long term effects of air pollution in Nantes by considering years of life lost as well as the number of attributable deaths. methods: the study population is classified in birth cohorts. for each cohort, 2 survival curves are built based on current mortality conditions: the first is built for current exposure to air pollution and the second for exposure to a lower reference level of air pollution. The area between the 2 curves represents years of life lost attributable to urban air pollution. results: the estimated number of premature deaths due to air pollution is approximately 56, or about 2% of the deaths of those older than 30 years. The health impact on the Nantes population is estimated at 27.2 years of life lost attributable to urban air pollution in 1999 and 2388.1 years of life lost for the 1999-2008 period. This amounts to a decrease of roughly 4 months in the life expectancy of those aged 30 years. Conclusion: This study, which also identifies and discusses relevant errors and uncertainty, confirmed that air pollution in Nantes has significant health effects and that chronic exposure plays an essential role in this impact. the number of years of life lost and the reduction in life expectancy provide new reasons to reject the assumption that health effects are limited to the premature deaths of terminally-ill people. the expected health gains in Nantes associated with reduced although still moderate air pollution levels are on the same scale as, and possibly better than, those found in 9

  1. Chronic exposure of killifish to a highly polluted environment desensitizes estrogen-responsive reproductive and biomarker genes

    Bugel, Sean M., E-mail: Sean.Bugel@oregonstate.edu [Department of Environmental and Molecular Toxicology, Environmental Health Sciences Center, Oregon State University, Corvallis, OR 97331 (United States); Bonventre, Josephine A. [Department of Environmental and Molecular Toxicology, Environmental Health Sciences Center, Oregon State University, Corvallis, OR 97331 (United States); White, Lori A. [Department of Biochemistry and Microbiology, Rutgers, The State University of New Jersey, New Brunswick, NJ 08901 (United States); Tanguay, Robert L. [Department of Environmental and Molecular Toxicology, Environmental Health Sciences Center, Oregon State University, Corvallis, OR 97331 (United States); Cooper, Keith R. [Department of Biochemistry and Microbiology, Rutgers, The State University of New Jersey, New Brunswick, NJ 08901 (United States)

    2014-07-01

    Highlights: • Reproductive biomarker genes in Newark Bay killifish are desensitized to estrogen. • Gene desensitization indicates pre-transcriptional effects on estrogen signaling. • Desensitization does not have a metabolic or epigenetic basis (gene methylation). • Modulation of vitellogenin and choriogenin genes correlates with reproductive impacts. • Choriogenin L appears less prone to false negatives and may be a sensitive biomarker. - Abstract: Reproductive and endocrine disruption is commonly reported in aquatic species exposed to complex contaminant mixtures. We previously reported that Atlantic killifish (Fundulus heteroclitus) from the chronically contaminated Newark Bay, NJ, exhibit multiple endocrine disrupting effects, including inhibition of vitellogenesis (yolk protein synthesis) in females and false negative vitellogenin biomarker responses in males. Here, we characterized the effects on estrogen signaling and the transcriptional regulation of estrogen-responsive genes in this model population. First, a dose–response study tested the hypothesis that reproductive biomarkers (vtg1, vtg2, chg H, chg Hm, chg L) in Newark Bay killifish are relatively less sensitive to 17β-estradiol at the transcriptional level, relative to a reference (Tuckerton, NJ) population. The second study assessed expression for various metabolism (cyp1a, cyp3a30, mdr) and estrogen receptor (ER α, ER βa, ER βb) genes under basal and estrogen treatment conditions in both populations. Hepatic metabolism of 17β-estradiol was also evaluated in vitro as an integrated endpoint for adverse effects on metabolism. In the third study, gene methylation was evaluated for promoters of vtg1 (8 CpGs) and vtg2 (10 CpGs) in both populations, and vtg1 promoter sequences were examined for single nucleotide polymorphism (SNPs). Overall, these studies show that multi-chemical exposures at Newark Bay have desensitized all reproductive biomarkers tested to estrogen. For example, at 10 ng

  2. The Difference between Anxiolytic and Anxiogenic Effects Induced by Acute and Chronic Alcohol Exposure and Changes in Associative Learning and Memory Based on Color Preference and the Cause of Parkinson-Like Behaviors in Zebrafish.

    Li, Xiang; Li, Xu; Li, Yi-Xiang; Zhang, Yuan; Chen, Di; Sun, Ming-Zhu; Zhao, Xin; Chen, Dong-Yan; Feng, Xi-Zeng

    2015-01-01

    We describe an interdisciplinary comparison of the effects of acute and chronic alcohol exposure in terms of their disturbance of light, dark and color preferences and the occurrence of Parkinson-like behavior in zebrafish through computer visual tracking, data mining, and behavioral and physiological analyses. We found that zebrafish in anxiolytic and anxious states, which are induced by acute and chronic repeated alcohol exposure, respectively, display distinct emotional reactions in light/dark preference tests as well as distinct learning and memory abilities in color-enhanced conditional place preference (CPP) tests. Additionally, compared with the chronic alcohol (1.0%) treatment, acute alcohol exposure had a significant, dose-dependent effect on anxiety, learning and memory (color preference) as well as locomotive activities. Acute exposure doses (0.5%, 1.0%, and 1.5%) generated an "inverted V" dose-dependent pattern in all of the behavioral parameters, with 1.0% having the greatest effect, while the chronic treatment had a moderate effect. Furthermore, by measuring locomotive activity, learning and memory performance, the number of dopaminergic neurons, tyrosine hydroxylase expression, and the change in the photoreceptors in the retina, we found that acute and chronic alcohol exposure induced varying degrees of Parkinson-like symptoms in zebrafish. Taken together, these results illuminated the behavioral and physiological mechanisms underlying the changes associated with learning and memory and the cause of potential Parkinson-like behaviors in zebrafish due to acute and chronic alcohol exposure. PMID:26558894

  3. N-Acetyl cysteine does not prevent liver toxicity from chronic low-dose plus subacute high-dose paracetamol exposure in young or old mice.

    Kane, Alice Elizabeth; Huizer-Pajkos, Aniko; Mach, John; McKenzie, Catriona; Mitchell, Sarah Jayne; de Cabo, Rafael; Jones, Brett; Cogger, Victoria; Le Couteur, David G; Hilmer, Sarah Nicole

    2016-06-01

    Paracetamol is an analgesic commonly used by people of all ages, which is well documented to cause severe hepatotoxicity with acute overexposures. The risk of hepatotoxicity from nonacute paracetamol exposures is less extensively studied, and this is the exposure most common in older adults. Evidence on the effectiveness of N-acetyl cysteine (NAC) for nonacute paracetamol exposures, in any age group, is lacking. This study aimed to examine the effect of long-term exposure to therapeutic doses of paracetamol and subacute paracetamol overexposure, in young and old mice, and to investigate whether NAC was effective at preventing paracetamol hepatotoxicity induced by these exposures. Young and old male C57BL/6 mice were fed a paracetamol-containing (1.33 g/kg food) or control diet for 6 weeks. Mice were then dosed orally eight times over 3 days with additional paracetamol (250 mg/kg) or saline, followed by either one or two doses of oral NAC (1200 mg/kg) or saline. Chronic low-dose paracetamol exposure did not cause hepatotoxicity in young or old mice, measured by serum alanine aminotransferase (ALT) elevation, and confirmed by histology and a DNA fragmentation assay. Subacute paracetamol exposure caused significant hepatotoxicity in young and old mice, measured by biochemistry (ALT) and histology. Neither a single nor double dose of NAC protected against this toxicity from subacute paracetamol in young or old mice. This finding has important clinical implications for treating toxicity due to different paracetamol exposure types in patients of all ages, and implies a need to develop new treatments for subacute paracetamol toxicity. PMID:26821200

  4. Effect of chronic prenatal ethanol exposure on nitric oxide synthase I and III proteins in the hippocampus of the near-term fetal guinea pig.

    Kimura, K A; Chiu, J; Reynolds, J N; Brien, J F

    1999-01-01

    Chronic prenatal ethanol exposure suppresses nitric oxide synthase (NOS) enzymatic activity, in the hippocampus of the near-term fetal guinea pig at gestational day (GD) 62. The objective of this study was to determine if this decrease in NOS activity is the result of decreased NOS I and NOS III protein expression. Pregnant guinea pigs received oral administration of 4 g ethanol/kg maternal body weight/day (n = 8), isocaloric-sucrose/pair feeding (n = 8), or water (n = 8) from GD 2 to GD 61. The NOS I and NOS III protein expression and localization in the hippocampus were determined using Western blot analysis and immunohistochemistry, respectively. The chronic ethanol regimen produced fetal body, brain, and hippocampal growth restriction compared with the isocaloric-sucrose/pair fed and water groups but did not affect the expression or localization of NOS I and NOS III proteins in the hippocampus. The decrease in NOS enzymatic activity induced by chronic prenatal ethanol exposure may be the result of posttranslational modification of NOS I and/or NOS III protein in the hippocampus of the near-term fetal guinea pig. PMID:10386828

  5. Fetal exposure to a diabetic intrauterine environment resulted in a failure of cord blood endothelial progenitor cell adaptation against chronic hypoxia

    Dincer UD

    2014-12-01

    Full Text Available U Deniz Dincer Department of Basic and Clinical Pharmacology, School of Medicine, Bezmialem Vakif University (BAVU, Fatih/Istanbul, Turkey Abstract: Gestational diabetes mellitus (GDM has long-term health consequences, and fetal exposure to a diabetic intrauterine environment increases cardiovascular risk for her adult offspring. Some part of this could be related to their endothelial progenitor cells (EPCs. Understanding the vessel-forming ability of human umbilical cord blood (HUCB-derived endothelial colony-forming cells (ECFCs against pathological stress such as GDM response to hypoxia could generate new therapeutic strategies. This study aims to investigate the role of chronic hypoxia in EPCs functional and vessel-forming ability in GDM subjects. Each ECFC was expressed in endothelial and pro-angiogenic specific markers, namely endothelial nitric oxide synthase (eNOS, platelet (PECAM-1 endothelial cell adhesion molecule 1, vascular endothelial-cadherin CdH5 (Ca-dependent cell adhesion molecule, vascular endothelial growth factor A, (VEGFA and insulin-like growth factor 1 (IGF1. Chronic hypoxia did not affect CdH5, but PECAM1 MRNA expressions were increased in control and GDM subjects. Control hypoxic and GDM normoxic VEGFA MRNA expressions and hypoxia-inducible factor 1-alpha (HIF1α protein expressions were significantly increased in HUCB ECFCs. GDM resulted in most failure of HUCB ECFC adaptation and eNOS protein expressions against chronic hypoxia. Chronic hypoxia resulted in an overall decline in HUCB ECFCs' proliferative ability due to reduction of clonogenic capacity and diminished vessel formation. Furthermore, GDM also resulted in most failure of cord blood ECFC adaptation against chronic hypoxic environment. Keywords: endothelial progenitor cells, gestational diabetes mellitus, chronic hypoxia, human cord blood

  6. Chronic TiO2 nanoparticle exposure to a benthic organism, Hyalella azteca: impact of solar UV radiation and material surface coatings on toxicity

    There is limited information on the chronic effects of nanomaterials to benthic organisms, as well as environmental mitigating factors that might influence this toxicity. The present study aimed to fill these data gaps by examining various growth endpoints (weight gain, instantaneous growth rate, and total protein content) for up to a 21 d sediment exposure of TiO2 nanoparticles (nano-TiO2) to a representative benthic species, Hyalella azteca. An uncoated standard, P25, and an Al(OH)3 coated nano-TiO2 used in commercial products were added to sediment at 20 mg/L or 100 mg/L Under test conditions, UV exposure alone was shown to be a greater cause of toxicity than even these high levels of nano-TiO2 exposure, indicating that different hazards need to be addressed in toxicity testing scenarios. In addition, this study showed the effectiveness of a surface coating on the decreased photoactivity of the material, as the addition of an Al(OH)3 coating showed a dramatic decrease in reactive oxygen species (ROS) production. However, this reduced photoactivity was found to be partially restored when the coating had been degraded, leading to the need for future toxicity tests which examine the implications of weathering events on particle surface coatings. - Highlights: • Chronic toxicity of nano-TiO2 to a benthic organism (Hyalella azteca) was examined. • Phototoxicity was investigated through exposure of solar simulated radiation (SSR). • The degradation of a surface coating resulted in an increase in photoactivity. • In this testing scenario, UV had a larger impact than chemical exposure in toxicity

  7. Chronic TiO{sub 2} nanoparticle exposure to a benthic organism, Hyalella azteca: impact of solar UV radiation and material surface coatings on toxicity

    Wallis, Lindsay K. [Office of Research and Development, Mid-Continent Ecology Division, National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Duluth, MN, 55804 (United States); Diamond, Stephen A. [Nanosafe Inc., Blacksburg, VA, 24060 (United States); Ma, Hongbo [University of Wisconsin-Milwaukee, Zilber School of Public Health, Milwaukee, WI, 53211 (United States); Hoff, Dale J. [Office of Research and Development, Mid-Continent Ecology Division, National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Duluth, MN, 55804 (United States); Al-Abed, Souhail R. [National Risk Management Research Laboratory, U.S. Environmental Protection Agency, Cincinnati, OH 45268 (United States); Li, Shibin, E-mail: lishibinepa@gmail.com [Office of Research and Development, Mid-Continent Ecology Division, National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Duluth, MN, 55804 (United States)

    2014-11-15

    There is limited information on the chronic effects of nanomaterials to benthic organisms, as well as environmental mitigating factors that might influence this toxicity. The present study aimed to fill these data gaps by examining various growth endpoints (weight gain, instantaneous growth rate, and total protein content) for up to a 21 d sediment exposure of TiO{sub 2} nanoparticles (nano-TiO{sub 2}) to a representative benthic species, Hyalella azteca. An uncoated standard, P25, and an Al(OH){sub 3} coated nano-TiO{sub 2} used in commercial products were added to sediment at 20 mg/L or 100 mg/L Under test conditions, UV exposure alone was shown to be a greater cause of toxicity than even these high levels of nano-TiO{sub 2} exposure, indicating that different hazards need to be addressed in toxicity testing scenarios. In addition, this study showed the effectiveness of a surface coating on the decreased photoactivity of the material, as the addition of an Al(OH){sub 3} coating showed a dramatic decrease in reactive oxygen species (ROS) production. However, this reduced photoactivity was found to be partially restored when the coating had been degraded, leading to the need for future toxicity tests which examine the implications of weathering events on particle surface coatings. - Highlights: • Chronic toxicity of nano-TiO{sub 2} to a benthic organism (Hyalella azteca) was examined. • Phototoxicity was investigated through exposure of solar simulated radiation (SSR). • The degradation of a surface coating resulted in an increase in photoactivity. • In this testing scenario, UV had a larger impact than chemical exposure in toxicity.

  8. Chronic low-level arsenic exposure causes gender-specific alterations in locomotor activity, dopaminergic systems, and thioredoxin expression in mice

    Arsenic (As) is a toxic metalloid widely present in the environment. Human exposure to As has been associated with the development of skin and internal organ cancers and cardiovascular disorders, among other diseases. A few studies report decreases in intelligence quotient (IQ), and sensory and motor alterations after chronic As exposure in humans. On the other hand, studies of rodents exposed to high doses of As have found alterations in locomotor activity, brain neurochemistry, behavioral tasks, and oxidative stress. In the present study both male and female C57Bl/6J mice were exposed to environmentally relevant doses of As such as 0.05, 0.5, 5.0, or 50 mg As/L of drinking water for 4 months, and locomotor activity was assessed every month. Male mice presented hyperactivity in the group exposed to 0.5 mg As/L and hypoactivity in the group exposed to 50 mg As/L after 4 months of As exposure, whereas female mice exposed to 0.05, 0.5, and 5.0 mg As/L exhibited hyperactivity in every monthly test during As exposure. Furthermore, striatal and hypothalamic dopamine content was decreased only in female mice. Also decreases in tyrosine hydroxylase (TH) and cytosolic thioredoxin (Trx-1) mRNA expression in striatum and nucleus accumbens were observed in male and female mice, respectively. These results indicate that chronic As exposure leads to gender-dependent alterations in dopaminergic markers and spontaneous locomotor activity, and down-regulation of the antioxidant capacity of the brain.

  9. Differential Impact of Stress Reduction Programs upon Ambulatory Blood Pressure among African American Adolescents: Influences of Endothelin-1 Gene and Chronic Stress Exposure

    Mathew J. Gregoski

    2012-01-01

    Full Text Available Stress-activated gene × environment interactions may contribute to individual variability in blood pressure reductions from behavioral interventions. We investigated effects of endothelin-1 (ET-1 LYS198ASN SNP and discriminatory stress exposure upon impact of 12-week behavioral interventions upon ambulatory BP (ABP among 162 prehypertensive African American adolescents. Following genotyping, completion of questionnaire battery, and 24-hour ABP monitoring, participants were randomized to health education control (HEC, life skills training (LST, or breathing awareness meditation (BAM. Postintervention ABP was obtained. Significant three-way interactions on ABP changes indicated that among ET-1 SNP carriers, the only group to show reductions was BAM from low chronic stress environments. Among ET-1 SNP noncarriers, under low chronic stress exposure, all approaches worked, especially BAM. Among high stress exposure noncarriers, only BAM resulted in reductions. If these preliminary findings are replicated via ancillary analyses of archival databases and then via efficacy trials, selection of behavioral prescriptions for prehypertensives will be edging closer to being guided by individual's underlying genetic and environmental factors incorporating the healthcare model of personalized preventive medicine.

  10. Food selection, growth and physiology in relation to dietary sodium chloride content in rainbow trout (Oncorhynchus mykiss) under chronic waterborne Cu exposure.

    Niyogi, S; Kamunde, C N; Wood, C M

    2006-05-01

    Waterborne Cu is toxic to Na(+) and Cl(-) regulation in freshwater fish, and Cu is taken up, at least in part, via the Na(+)-transport pathway in the gills. Therefore, we hypothesized that freshwater fish may mitigate the toxic effects of waterborne Cu by selecting a NaCl-enriched diet over a normal diet. We tested this hypothesis in juvenile rainbow trout (Oncorhynchus mykiss) by offering them the choice between NaCl-enriched (1.9 mmol g(-1)Na(+)) and normal (0.2 mmol g(-1)Na(+)) diets under a chronic waterborne Cu exposure of 55 microg L(-1) for a period of 28 days. Contrary to expectation, trout exhibited a preference for NaCl-enriched diet under control conditions, while exposure to chronic waterborne Cu severely disrupted their normal feeding pattern with an accompanying loss of preference for the NaCl-enriched diet. Waterborne Cu exposure also severely affected appetite and growth. Both appetite and growth gradually recovered with time, but remained significantly impaired relative to Cu-unexposed fish until the end of the exposure. Waterborne Cu exposure also significantly increased Cu accumulations in target organs (gill, liver, and gut), plasma and whole body. However, Cu accumulation decreased substantially towards the end of the exposure in target organs and whole body as well as in plasma in Cu-exposed fish with dietary choice relative to Cu-exposed fish with normal diet. These adjustments were concurrent with the gradual recovery of appetite, which also led to increased ingestion of the NaCl-enriched diet. Interestingly, this elevated dietary uptake of NaCl produced significant stimulation of Na(+) efflux in Cu-exposed fish. Subsequently, it also led to significant elevation of Na(+) levels in target organs and whole body, and restored the decrease of plasma Na(+) and Cl(-) levels in Cu-exposed fish. The NaCl supplemented diet appeared to be beneficial in compensating Na(+) and Cl(-) losses from the body induced by waterborne Cu. Overall, these results

  11. The modification of the function of the systems of the second messengers in present of dexamethasone in thymocytes of rats after chronic gamma-exposure

    The object of the study was the thymocytes of intact rats and the cells of rats after chronic gamma-irradiation (1 Gy) on the 30th day after the irradiation. The level of the cytoplasmic [Ca2+]i was investigated by using fluorescent probe Fura-2/AM. It was foundation that the effect of the influence of the dexamethasone was more vivid in the cells after the irradiation. The radio-immune method was used for investigating the level of the cAMP in the thymocytes. It was discovered that chronic gamma-exposure to dose 1,0 Gy caused the change in the level of the intracellular cAMP. We can proposal that the influence of gamma-irradiation probably may initiate the modification of the system of the calcium homeostasis and the cyclic nucleotides. (authors)

  12. A multiple endpoint analysis of the effects of chronic exposure to sediment contaminated with Deepwater Horizon oil on juvenile Southern flounder and their associated microbiomes

    Brown-Peterson, Nancy J., E-mail: nancy.brown-peterson@usm.edu [Department of Coastal Sciences, The University of Southern Mississippi, 703 East Beach Dr., Ocean Springs, MS 39564 (United States); Krasnec, Michelle, E-mail: MKrasnec@stratusconsulting.com [Abt Associates, 1881 Ninth Street, Suite 201, Boulder, Colorado 80302 (United States); Takeshita, Ryan, E-mail: RTakeshita@stratusconsulting.com [Abt Associates, 1881 Ninth Street, Suite 201, Boulder, Colorado 80302 (United States); Ryan, Caitlin N., E-mail: Caitlin.ryan@ttu.edu [The Institute of Environmental and Human Health, Department of Environmental Toxicology, Texas Tech University, Box 41163, Lubbock, TX 79409 (United States); Griffitt, Kimberly J., E-mail: kim.griffitt@gmail.com [Department of Coastal Sciences, The University of Southern Mississippi, 703 East Beach Dr., Ocean Springs, MS 39564 (United States); Lay, Claire, E-mail: claymsc@stratusconsulting.com [Abt Associates, 1881 Ninth Street, Suite 201, Boulder, Colorado 80302 (United States); Mayer, Gregory D., E-mail: greg.mayer@ttu.edu [The Institute of Environmental and Human Health, Department of Environmental Toxicology, Texas Tech University, Box 41163, Lubbock, TX 79409 (United States); Bayha, Keith M., E-mail: kmbayha@gmail.com [Department of Coastal Sciences, The University of Southern Mississippi, 703 East Beach Dr., Ocean Springs, MS 39564 (United States); Hawkins, William E., E-mail: william.hawkins@usm.edu [Department of Coastal Sciences, The University of Southern Mississippi, 703 East Beach Dr., Ocean Springs, MS 39564 (United States); Lipton, Ian, E-mail: ianlipton@stratusconsulting.com [Abt Associates, 1881 Ninth Street, Suite 201, Boulder, Colorado 80302 (United States); Morris, Jeffrey, E-mail: JMorrisMSCanyon252@stratusconsulting.com [Abt Associates, 1881 Ninth Street, Suite 201, Boulder, Colorado 80302 (United States); and others

    2015-08-15

    Highlights: • Juvenile southern flounder were exposed to sediment mixed with different amount of oil from the Deepwater Horizon spill. • The exposure was performed for 32 days, with growth and survival assessed throughout. • After the termination of the experiment, the survivors were examined at multiple endpoints, including histopathology and microbiome analysis. • The results indicated that the flounder were adversely affected at each endpoint examined. • Growth and survival were significantly reduced. • Histopathology found effects on gills and livers of exposed fish. • The microbiomes of the exposed fish were significantly altered by the exposure to sediment-associated oil in both gills and intestines. - Abstract: Exposure to oiled sediments can negatively impact the health of fish species. Here, we examine the effects of chronic exposure of juvenile southern flounder, Paralichthys lethostigma, to a sediment-oil mixture. Oil:sediment mixtures are persistent over time and can become bioavailable following sediment perturbation or resuspension. Juvenile flounder were exposed for 32 days under controlled laboratory conditions to five concentrations of naturally weathered Macondo MC252 oil mixed into uncontaminated, field-collected sediments. The percent composition of individual polycyclic aromatic hydrocarbons (PAHs) of the weathered oil did not change after mixing with the sediment. Spiked exposure sediments contained 0.04–395 mg/kg tPAH50 (sum of 50 individual PAH concentration measurements). Mortality increased with both exposure duration and concentration of sediment-associated PAHs, and flounder exposed to concentrations above 8 mg/kg tPAH50 showed significantly reduced growth over the course of the experiment. Evident histopathologic changes were observed in liver and gill tissues of fish exposed to more than 8 mg/kg tPAH50. All fish at these concentrations showed hepatic intravascular congestion, macrovesicular hepatic vacoulation

  13. The effects of chronic cadmium exposure on repeat swimming performance and anaerobic metabolism in brown trout (Salmo trutta) and lake whitefish (Coregonus clupeaformis).

    Cunningham, Jessie L; McGeer, James C

    2016-04-01

    This study investigates the effect of chronic Cd exposure on the ability to perform repeat swim challenges in brown trout (Salmo trutta) and lake whitefish (Coregonus clupeaformis). Fish were exposed to waterborne Cd (18nM) in moderately hard water (120mgL(-1) CaCO3) for 30 days. This level of exposure has been shown to cause sublethal physiological disruption and acclimation responses but no impairment of sustained swimming capacity (Ucrit) in single swim challenges. Swim trials were done over the course of the exposure and each one consisted of an initial swim to 85% of the Ucrit of control fish, a 30min recovery period and finally a second swim challenge to determine Ucrit. Plasma and tissue samples were collected before and after each of the swim periods. As expected from previous studies, Cd exposure resulted in significant accumulation of Cd in gills, liver and kidney but not in white muscle. Exposure also induced a loss of plasma Ca followed by subsequent recovery (in lake whitefish but not brown trout) with few mortalities (100% survival for lake whitefish and 93% for brown trout). Both control and exposed fish swam to 85% of the single swim Ucrit and no differences in performance were seen. The Ucrit of unexposed controls in the second swim challenges were not different from the single swim Ucrit. However, second swim performance was significantly reduced in Cd exposed fish, particularly after a week of exposure where 31% and 38% reductions were observed for brown trout and lake whitefish respectively. Swimming to 85% Ucrit resulted in metabolic expenditure with little recovery after 30min. Few differences were observed between control and Cd exposed fish with the exception of a reduction in resting white muscle ATP stores of Cd exposed fish after 1 week of exposure. The results show that chronic sublethal Cd exposure results in an impairment of swimming ability in repeat swim challenges but this impairment is generally not related to metabolic processes

  14. A multiple endpoint analysis of the effects of chronic exposure to sediment contaminated with Deepwater Horizon oil on juvenile Southern flounder and their associated microbiomes

    Highlights: • Juvenile southern flounder were exposed to sediment mixed with different amount of oil from the Deepwater Horizon spill. • The exposure was performed for 32 days, with growth and survival assessed throughout. • After the termination of the experiment, the survivors were examined at multiple endpoints, including histopathology and microbiome analysis. • The results indicated that the flounder were adversely affected at each endpoint examined. • Growth and survival were significantly reduced. • Histopathology found effects on gills and livers of exposed fish. • The microbiomes of the exposed fish were significantly altered by the exposure to sediment-associated oil in both gills and intestines. - Abstract: Exposure to oiled sediments can negatively impact the health of fish species. Here, we examine the effects of chronic exposure of juvenile southern flounder, Paralichthys lethostigma, to a sediment-oil mixture. Oil:sediment mixtures are persistent over time and can become bioavailable following sediment perturbation or resuspension. Juvenile flounder were exposed for 32 days under controlled laboratory conditions to five concentrations of naturally weathered Macondo MC252 oil mixed into uncontaminated, field-collected sediments. The percent composition of individual polycyclic aromatic hydrocarbons (PAHs) of the weathered oil did not change after mixing with the sediment. Spiked exposure sediments contained 0.04–395 mg/kg tPAH50 (sum of 50 individual PAH concentration measurements). Mortality increased with both exposure durat