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Sample records for acute single exposure

  1. A case of acute psychosis in a patient following exposure to a single high dose of styrene.

    PubMed

    Moon, Eunsoo; Suh, Hwagyu; Lee, Byung Dae; Park, Je Min; Lee, Young Min; Jeong, Hee Jeong

    2015-09-01

    We report a case of acute psychotic symptoms following exposure to a single high dose of styrene monomer. The 24-year-old male patient showed psychotic and cognitive symptoms immediately after exposure. His psychotic symptoms included auditory hallucinations and delusions of reference. Brain magnetic resonance imaging, electroencephalography, and laboratory examinations were performed to evaluate any other causes. The clinical, neuroimaging, and laboratory review in this case suggested that the suddenly developed psychotic symptoms that led to chronic deterioration were caused by the single exposure to styrene monomer. This is the first recent report in which acute psychotic symptoms developed from a single high dose of styrene suffocation compared with previous findings showing symptoms because of long-term low-dose exposure. PMID:26184570

  2. Response of swine skin microvasculature to acute single exposures of x-rays: quantification of endothelial changes

    SciTech Connect

    Archambeau, J.O.; Ines, A.; Fajardo, L.F.

    1984-04-01

    An acute single X-ray exposure of 2300 R produces in swine skin a moist reaction (ulceration) that appears at 17 days, heals by 32 days, and may break down again between 42 and 70 days. Initial studies quantified the epidermal population density changes during this 70-day period. This study was designed to quantify the density changes occuring in the endothelial cell population of the dermal microvasculature. While the basal population decreases to a nadir of 10% control by 24 days, the endothelial population remains at control levels. Beyond 24 days, the endothelial cell density decreases abruptly to 50% as the epidermal cell density returns to control levels and overshoots by 20% at 32 days. Subsequently, both populations decrease to zero by 57 days. Endothelial cell loss parallels a similar decrease in vascular lumen density. These finding indicate that the initial moist reaction results from a radiation-induced loss of epidermal cells, while the second reaction results from the loss of dermal microvasculature.

  3. Acute exposure to rhodamine B.

    PubMed

    Dire, D J; Wilkinson, J A

    1987-01-01

    Rhodamine B is a red colored dye that is used in cosmetic products. We report a case of 17 patients who were exposed to aerosolized Rhodamine B inside a maintenance shop. The mean duration of exposure was 26 minutes (range 2-65). Sixteen of the patients (94%) complained of acute symptoms including: burning of the eyes (82%), excessive tearing (47%), nasal burning (41%), nasal itching (35%), chest pain/tightness (35%), rhinorhea (29%), cough (29%), dyspnea (29%), burning of the throat (24%), burning/pruritic skin (24%), chest burning (12%), headache (6%), and nausea (6%). All of the patients had resolution of their symptoms within 24 hours (less than 4 hours in 63%). Acute exposure to Rhodamine B resulted in transient mucous membrane and skin irritation without evidence of serious sequellae. PMID:3446824

  4. Single oral acute fluoride exposure causes changes in cardiac expression of oxidant and antioxidant enzymes, apoptotic and necrotic markers in male rats.

    PubMed

    Panneerselvam, Lakshmikanthan; Govindarajan, Vimal; Ameeramja, Jaishabanu; Nair, Harikumaran Raveendran; Perumal, Ekambaram

    2015-12-01

    Several studies have shown that acute fluoride (F(-)) exposure impairs cardiac function, but the molecular mechanism is not clear. In order to study this, male Wistar rats were treated with single oral doses of 45 and 90 mg/kg F(-) for 24 h. A significant accumulation of F(-) was found in the serum and myocardium of experimental rats. F(-) treatment causes myocardial necrosis as evident from increased levels of myocardial troponin I, creatine kinase, lactate dehydrogenase and aspartate transaminase. In addition, F(-) induces myocardial oxidative stress via increased reactive oxygen species, lipid peroxidation, protein carbonyl content and nitrate levels along with decreased in the levels of enzymatic (superoxide dismutase 2, catalase, glutathione peroxidase and glutathione s transferase pi class) and non-enzymatic (reduced glutathione) antioxidants. Notably, F(-) triggers myocardial apoptosis through altered Bax/Bcl2 ratio and increased cytochrome c, caspase 3p20 and terminal deoxynucleotidyl transferase dUTP nick end labeled positive cells. An increased cardiac expression of Nox4 and p38α MAPK in F(-) treated rats indicates the oxidative and apoptotic damage. Moreover, ultra-structural changes, histopathological and luxol fast blue staining demonstrates the degree of myocardial damage at subcellular level. Taken together, these findings reveal that acute F(-) exposure causes cardiac impairment by altering the expression of oxidative stress, apoptosis and necrotic markers. PMID:26455266

  5. Acute and long-lasting cardiac changes following a single whole-body exposure to sarin vapor in rats.

    PubMed

    Allon, N; Rabinovitz, I; Manistersky, E; Weissman, B A; Grauer, E

    2005-10-01

    Epinephrine-induced arrhythmias (EPIA) are known to be associated with local cardiac cholinergic activation. The present study examined the development of QT prolongation and the effect on EPIA of whole-body exposure of animals to a potent acetylcholine esterase inhibitor. Freely moving rats were exposed to sarin vapor (34.2 +/- 0.8 microg/liter) for 10 min. The electrocardiograms (ECG) of exposed and control animals were monitored every 2 weeks for 6 months. One and six months post exposure, rats were challenged with epinephrine under anesthesia, and the threshold for arrhythmias was determined. Approximately 35% of the intoxicated rats died within 24 h of sarin exposure. Additional occasional deaths were recorded for up to 6 months (final mortality rate of 48%). Surviving rats showed, agitation, aggression, and weight loss compared to non-exposed rats, and about 20% of them experienced sporadic convulsions. Sarin-challenged rats with severe symptoms demonstrated QT segment prolongation during the first 2-3 weeks after exposure. The EPIA that appeared at a significantly lower blood pressure in the treated group in the first month after intoxication lasted for up to 6 months. This decrease in EPIA threshold was blocked by atropine and methyl-atropine. Three months post exposure no significant changes were detected in either k(D) or B(max) values of (3)H-N-methyl scopolamine binding to heart homogenates, or in the affinity of carbamylcholine to cardiac muscarinic receptors. The increase in the vulnerability to develop arrhythmias long after accidental or terror-related organophosphate (OP) intoxication, especially under challenging conditions such as stress or intensive physical exercise, may explain the delayed mortality observed following OP exposure. PMID:16033992

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

    EPA Science Inventory

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

  7. Acute toxicant exposure and cardiac autonomic dysfunction from smoking a single narghile waterpipe with tobacco and with a "healthy" tobacco-free alternative.

    PubMed

    Cobb, Caroline O; Sahmarani, Kamar; Eissenberg, Thomas; Shihadeh, Alan

    2012-11-23

    Tobacco smoking using a waterpipe (narghile, hookah, shisha) has become a global epidemic. Unlike cigarette smoking, little is known about the health effects of waterpipe use. One acute effect of cigarette smoke inhalation is dysfunction in autonomic regulation of the cardiac cycle, as indicated by reduction in heart rate variability (HRV). Reduced HRV is implicated in adverse cardiovascular health outcomes, and is associated with inhalation exposure-induced oxidative stress. Using a 32 participant cross-over study design, we investigated toxicant exposure and effects of waterpipe smoking on heart rate variability when, under controlled conditions, participants smoked a tobacco-based and a tobacco-free waterpipe product promoted as an alternative for "health-conscious" users. Outcome measures included HRV, exhaled breath carbon monoxide (CO), plasma nicotine, and puff topography, which were measured at times prior to, during, and after smoking. We found that waterpipe use acutely decreased HRV (p<0.01 for all measures), independent of product smoked. Plasma nicotine, blood pressure, and heart rate increased only with the tobacco-based product (p<0.01), while CO increased with both products (p<0.01). More smoke was inhaled during tobacco-free product use, potentially reflecting attempted regulation of nicotine intake. The data thus indicate that waterpipe smoking acutely compromises cardiac autonomic function, and does so through exposure to smoke constituents other than nicotine. PMID:23059956

  8. Accidental acute exposure to doxorubicin.

    PubMed

    Curran, C F; Luce, J K

    1989-12-01

    Accidental ocular exposure to doxorubicin was followed by no reaction or rapidly resolving conjunctivitis in 13 of 15 cases (87%). In the two remaining cases, persistent photophobia and chronic inflammation were reported. Of 28 accidental exposures to sites other than the eyes, no reactions or rapidly resolving local reactions were reported in 24 cases (86%). Nurses are at particular risk for accidental exposure to doxorubicin and accounted for 20 of the 43 reported exposures (47%). PMID:2590899

  9. Acute arsenic intoxication from environmental arsenic exposure

    SciTech Connect

    Franzblau, A.; Lilis, R. )

    1989-11-01

    Reports of acute arsenic poisoning arising from environmental exposure are rare. Two cases of acute arsenic intoxication resulting from ingestion of contaminated well water are described. These patients experienced a variety of problems: acute gastrointestinal symptoms, central and peripheral neurotoxicity, bone marrow suppression, hepatic toxicity, and mild mucous membrane and cutaneous changes. Although located adjacent to an abandoned mine, the well water had been tested for microorganisms only and was found to be safe. Regulations for testing of water from private wells for fitness to drink are frequently nonexistent, or only mandate biologic tests for microorganisms. Well water, particularly in areas near mining activity, should be tested for metals.

  10. In Vivo Nanodetoxication for Acute Uranium Exposure.

    PubMed

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

    2015-01-01

    Accidental exposure to uranium is a matter of concern, as U(VI) is nephrotoxic in both human and animal models, and its toxicity is associated to chemical toxicity instead of radioactivity. We synthesized different PAMAM G4 and G5 derivatives in order to prove their interaction with uranium and their effect on the viability of red blood cells in vitro. Furthermore, we prove the effectiveness of the selected dendrimers in an animal model of acute uranium intoxication. The dendrimer PAMAM G4-Lys-Fmoc-Cbz demonstrated the ability to chelate the uranyl ion in vivo, improving the biochemical and histopathologic features caused by acute intoxication with uranium. PMID:26083036

  11. A FIM Study to Assess Safety and Exposure of Inhaled Single Doses of AP301—A Specific ENaC Channel Activator for the Treatment of Acute Lung Injury

    PubMed Central

    Schwameis, Richard; Eder, Sandra; Pietschmann, Helmut; Fischer, Bernhard; Mascher, Hermann; Tzotzos, Susan; Fischer, Hendrik; Lucas, Rudolf; Zeitlinger, Markus; Hermann, Robert

    2014-01-01

    AP301 is an activator of ENaC-mediated Na+ uptake for the treatment of pulmonary permeability edema in acute respiratory distress syndrome (ARDS). The purpose of this “first-in-man” study was to examine local and systemic safety and systemic exposure of ascending single doses of AP301, when inhaled by healthy male subjects. In a double-blind, placebo-controlled study, 48 healthy male subjects were randomized to 6 ascending dose groups (single doses up to 120 mg) of 8 subjects each (3:1 randomization of AP301: placebo). Serial assessments included spirometry, exhaled nitric oxide (eNO), vital signs, ECG, safety laboratory, adverse events (AE), and blood samples for the quantification of AP301 in plasma. Descriptive statistics was applied. All 48 subjects received treatment, and completed the study as per protocol. No serious, local (e.g., hoarseness, cough, bronchospasm), or dose-limiting AEs were noted. None of the assessments indicated notable dose or time-related alterations of safety outcomes. Observed AP301 systemic exposure levels were very low, with mean Cmax values of <2.5 ng/mL in the highest dose groups. Inhaled AP301 single doses up to 120 mg were safe and well tolerated by healthy male subjects. Distribution of inhaled AP301 was largely confined to the lung, as indicated by very low AP301 systemic exposure levels. PMID:24515273

  12. Acute radiodermatitis from occupational exposure to iridium 192

    SciTech Connect

    Becker, J.; Rosen, T. )

    1989-12-01

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

  13. Susceptibility to ozone-induced inflammation. II. Separate loci control responses to acute and subacute exposures

    SciTech Connect

    Kleeberger, S.R.; Levitt, R.C.; Zhang, L.Y. )

    1993-01-01

    We demonstrated previously that inbred strains of mice are differentially susceptible to acute (3 h) and subacute (48 h) exposures to 2 parts per million (ppm) ozone (O3) and 0.30 ppm O3, respectively. Genetic studies with O3-resistant C3H/HeJ and O3-susceptible C57BL/6J strains have indicated that susceptibility to each of these O3 exposures is under Mendelian (single gene) control. In the present study, we hypothesized that the same gene controls susceptibility to the airway inflammatory responses to 2 ppm and 0.30 ppm O3 exposures. To test this hypothesis, airway inflammation was induced in 10 BXH and 16 BXD recombinant inbred (RI) strains of mice by acute as well as subacute O3 exposures. Airway inflammation was assessed by counting the number of polymorphonuclear leukocytes (PMNs) in bronchoalveolar lavage (BAL) returns obtained immediately after 48-h subacute exposure to 0.30 ppm O3, or 6 h after 3 h acute exposure to 2 ppm O3. Each RI strain was classified as susceptible or resistant to each exposure, based on a comparison of mean numbers of PMNs with those of the respective progenitor strains. For each RI set, a phenotypic strain distribution pattern (SDP) was thus derived for each exposure regimen, and the SDPs were then compared for concordance. Among the BXH RI strains, 4 of 10 responded discordantly to the two exposures: 3 were susceptible to acute exposure and resistant to subacute exposure, whereas 1 was conversely susceptible. Among the BXD RI strains, 4 of 16 were discordant: 1 was susceptible to acute exposure, and resistant to subacute exposure, whereas 3 were conversely susceptible.

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

    SciTech Connect

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

    2010-04-15

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

  15. Biomarkers of acute respiratory allergen exposure: screening for sensitization potential.

    PubMed

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

    2010-04-15

    Effective hazard screening will require the development of high-throughput or in vitro assays for the identification of potential sensitizers. The goal of this preliminary study was to identify potential biomarkers that differentiate the response to allergens vs non-allergens following an acute exposure in naïve individuals. Female BALB/c mice received a single intratracheal aspiration exposure to Metarhizium anisopliae crude antigen (MACA) or bovine serum albumin (BSA) in Hank's Balanced Salt Solution (HBSS) or HBSS alone. Mice were terminated after 1, 3, 6, 12, 18 and 24 h. Bronchoalveolar lavage fluid (BALF) was evaluated to determine total and differential cellularity, total protein concentration and LDH activity. RNA was isolated from lung tissue for microarray analysis and qRT-PCR. MACA administration induced a rapid increase in BALF neutrophils, lymphocytes, eosinophils and total protein compared to BSA or HBSS. Microarray analysis demonstrated differential expression of genes involved in cytokine production, signaling, inflammatory cell recruitment, adhesion and activation in 3 and 12 h MACA-treated samples compared to BSA or HBSS. Further analyses allowed identification of approximately 100 candidate biomarker genes. Eleven genes were selected for further assessment by qRT-PCR. Of these, 6 demonstrated persistently increased expression (Ccl17, Ccl22, Ccl7, Cxcl10, Cxcl2, Saa1), while C3ar1 increased from 6-24 h. In conclusion, a single respiratory exposure of mice to an allergenic mold extract induces an inflammatory response which is distinct in phenotype and gene transcription from the response to a control protein. Further validation of these biomarkers with additional allergens and irritants is needed. These biomarkers may facilitate improvements in screening methods. PMID:20045013

  16. Chronic Acetaminophen Exposure in Pediatric Acute Liver Failure

    PubMed Central

    Alonso, Estella M.; Im, Kelly; Belle, Steven H.; Squires, Robert H.

    2013-01-01

    BACKGROUND: Acetaminophen (N-acetyl-p-aminophenol [APAP]) is a widely used medication that can cause hepatotoxicity. We examined characteristics and outcomes of children with chronic exposure (CE) to APAP in the multinational Pediatric Acute Liver Failure (PALF) Study. METHODS: A total of 895 children enrolled from 2002 to 2009 were grouped by APAP exposure history as: CE (received multiple doses \\x{2265}2 days; n = 83), single dose exposure (SE; n = 85), and no exposure (NE; n = 498). CE was the reference group for pairwise comparisons. Median values are shown. RESULTS: Patients with CE compared with those with SE were younger (3.5 vs 15.2 years, P < .0001), less likely to be female (46% vs 82%, P < .0001), and more likely to be Hispanic (25% vs 7%, P = .001), but they did not differ significantly from the NE group. At enrollment, total bilirubin was lower with CE than with NE (3.2 vs 13.1 mg/dL, P < .001). Alanine aminotransferase levels were higher with CE than with NE (2384 vs 855 IU/L, P < .0001), but lower than with SE (5140 IU/L, P < .0001). Survival without liver transplantation at 21 days was worse for CE than for SE (68% vs 92%, P = .0004) but better than for NE (49%, P = .008). CONCLUSIONS: Children in the PALF study with CE had lower bilirubin and higher alanine aminotransferase than those with NE. Outcomes with CE were worse than with SE but better than with NE. Potential reasons for this outcomes advantage over non–APAP-exposed subjects should be explored. PMID:23439908

  17. ACUTE CADMIUM EXPOSURE AND OVARIAN STEROIDOGENESIS IN CYCLING AND PREGNANT RATS

    EPA Science Inventory

    The purpose of this study was to evaluate the effect(s) of acute in vivo cadmium exposure on steroidogenesis in rat ovaries during different reproductive states. prague-Dawley rats were injected subcutaneously on the day of diestrus, or on day 7 or 16 of gestation with a single d...

  18. ACUTE SULFOLANE EXPOSURE PRODUCES TEMPERATURE-INDEPENDENT AND DEPENDENT CHANGES IN VISUAL EVOKED POTENTIALS

    EPA Science Inventory

    The report describes the consequences of acute exposure to sulfolane upon the visual system, as measured using flash evoked potential (FEPs) and pattern reversal evoked potentials (PREPs). A single injection of either 1/2 or 1/4, but not 1/8 the i.p. LD50 (1600 mg/kg) produced si...

  19. EFFECTS OF EXPOSURE TO PEROXYACETYL NITRATE ON SUSCEPTIBILITY TO ACUTE AND CHRONIC BACTERIAL INFECTION

    EPA Science Inventory

    A significant increase in mortality due to acute respiratory pneumonia caused by inhalation of Streptococcus pyogenes aerosol was seen after a single 3-h exposure of mice to 14.8-28.4 mg/cu.m. peroxyacetyl nitrate (PAN). The excess mortality ranged from 8 to 39% and the decrease ...

  20. Formaldehyde exposure and acute health effects study

    SciTech Connect

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

    1989-01-01

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

  1. Pesticide residues in food--acute dietary exposure.

    PubMed

    Hamilton, Denis; Ambrus, Arpád; Dieterle, Roland; Felsot, Allan; Harris, Caroline; Petersen, Barbara; Racke, Ken; Wong, Sue-Sun; Gonzalez, Roberto; Tanaka, Keiji; Earl, Mike; Roberts, Graham; Bhula, Raj

    2004-04-01

    Consumer risk assessment is a crucial step in the regulatory approval of pesticide use on food crops. Recently, an additional hurdle has been added to the formal consumer risk assessment process with the introduction of short-term intake or exposure assessment and a comparable short-term toxicity reference, the acute reference dose. Exposure to residues during one meal or over one day is important for short-term or acute intake. Exposure in the short term can be substantially higher than average because the consumption of a food on a single occasion can be very large compared with typical long-term or mean consumption and the food may have a much larger residue than average. Furthermore, the residue level in a single unit of a fruit or vegetable may be higher by a factor (defined as the variability factor, which we have shown to be typically x3 for the 97.5th percentile unit) than the average residue in the lot. Available marketplace data and supervised residue trial data are examined in an investigation of the variability of residues in units of fruit and vegetables. A method is described for estimating the 97.5th percentile value from sets of unit residue data. Variability appears to be generally independent of the pesticide, the crop, crop unit size and the residue level. The deposition of pesticide on the individual unit during application is probably the most significant factor. The diets used in the calculations ideally come from individual and household surveys with enough consumers of each specific food to determine large portion sizes. The diets should distinguish the different forms of a food consumed, eg canned, frozen or fresh, because the residue levels associated with the different forms may be quite different. Dietary intakes may be calculated by a deterministic method or a probabilistic method. In the deterministic method the intake is estimated with the assumptions of large portion consumption of a 'high residue' food (high residue in the sense

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

    PubMed Central

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

    2012-01-01

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

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

    USGS Publications Warehouse

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

    2012-01-01

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

  4. VISUAL SYSTEM DYSFUNCTION FOLLOWING ACUTE TRIMETHYLTIN EXPOSURE IN RATS

    EPA Science Inventory

    Trimethyltin (TMT) has been shown to produce damage in the limbic system and several other brain areas. To date, damage to sensory systems has not been reported. The present study investigated the integrity of the visual system following acute exposure to TMT. Rats were chronical...

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

    EPA Science Inventory

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

  6. PREDICTORS OF INDIVIDUAL DIFFERENCES IN ACUTE RESPONSE TO OZONE EXPOSURE

    EPA Science Inventory

    The purposes of this study were to identify personal characteristics which predict individual differences in acute response to ozone exposure and to develop a predictive model for decrements in FEV1 as a function of ozone concentration and individual predictors. esponse and predi...

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

    EPA Science Inventory

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

  8. Health Impacts from Acute Radiation Exposure

    SciTech Connect

    Strom, Daniel J.

    2003-09-30

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

  9. Acute effects of bright light exposure on cortisol levels.

    PubMed

    Jung, Christopher M; Khalsa, Sat Bir S; Scheer, Frank A J L; Cajochen, Christian; Lockley, Steven W; Czeisler, Charles A; Wright, Kenneth P

    2010-06-01

    Multisynaptic neural and endocrine pathways from the suprachiasmatic nucleus of the hypothalamus have been hypothesized to communicate circadian and photic information to the adrenal glands. In humans, light exposure has been reported to have no effect, increase, or decrease cortisol levels. These inconsistent findings in humans may be related to differences among studies including the intensity (approximately 500 to 5500 lux), duration (15 min to 4 h), and circadian phase of light exposure. The authors assessed the influence of exposure to bright light on cortisol levels in humans during the rising and descending phases of the circadian rhythm of cortisol, that is, when cortisol levels are high. Twenty healthy men and women were studied using a within-subject research design. Subjects were studied in an environment free of time cues for 9 to 10 days. Subjects received a 6.7-h exposure of bright light (approximately 10,000 lux; equivalent to ambient light intensity just after sunrise or just before sunset) or dim light (approximately 3 lux; equivalent to candle light) during the biological night and morning. Bright light exposure significantly reduced plasma cortisol levels at both circadian phases studied, whereas dim light exposure had little effect on cortisol levels. The finding of an acute suppressive effect of bright light exposure on cortisol levels supports the existence of a mechanism by which photic information can acutely influence the human adrenal glands. PMID:20484692

  10. Single dose dipyrone for acute postoperative pain

    PubMed Central

    Derry, Sheena; Faura, Clara; Edwards, Jayne; McQuay, Henry J; Moore, R Andrew

    2014-01-01

    Background Dipyrone (metamizole) is a non-steroidal anti-inflammatory drug used in some countries to treat pain (postoperative, colic, cancer, and migraine); it is banned in others because of an association with life-threatening blood agranulocytosis. This review updates a 2001 Cochrane review, and no relevant new studies were identified, but additional outcomes were sought. Objectives To assess the efficacy and adverse events of single dose dipyrone in acute postoperative pain. Search methods The earlier review searched CENTRAL, MEDLINE, EMBASE, LILACS and the Oxford Pain Relief Database to December 1999. For the update we searched CENTRAL, MEDLINE,EMBASE and LILACS to February 2010. Selection criteria Single dose, randomised, double-blind, placebo or active controlled trials of dipyrone for relief of established moderate to severe postoperative pain in adults. We included oral, rectal, intramuscular or intravenous administration of study drugs. Data collection and analysis Studies were assessed for methodological quality and data extracted by two review authors independently. Summed total pain relief over six hours (TOTPAR) was used to calculate the number of participants achieving at least 50% pain relief. Derived results were used to calculate, with 95% confidence intervals, relative benefit compared to placebo, and the number needed to treat (NNT) for one participant to experience at least 50% pain relief over six hours. Use and time to use of rescue medication were additional measures of efficacy. Information on adverse events and withdrawals was collected. Main results Fifteen studies tested mainly 500 mg oral dipyrone (173 participants), 2.5 g intravenous dipyrone (101), 2.5 g intramuscular dipyrone (99); fewer than 60 participants received any other dose. All studies used active controls (ibuprofen, paracetamol, aspirin, flurbiprofen, ketoprofen, dexketoprofen, ketorolac, pethidine, tramadol, suprofen); eight used placebo controls. Over 70% of participants

  11. Single fibre electromyographic changes in man after organophosphate exposure.

    PubMed

    Baker, D J; Sedgwick, E M

    1996-05-01

    1. Neuromuscular (NM) changes resulting from organophosphate exposure are known to be complex. After severe acute poisoning recovery from initial depolarisation paralysis may be followed in a limited number of cases by onset of a non-depolarisation paralysis (the Intermediate Syndrome). It is not clear whether this block arises subclinically in all cases of poisoning as a sequel to the initial depolarisation. 2. Single fibre electromyography (SFEMG) is a sensitive clinical neurophysiological technique allowing detection of subclinical changes at the neuromuscular junction. In the study reported it has been used to examine changes in NM transmission in the forearm of fit volunteers exposed to a low level of sarin (isopropyl methyl phosphonofluoridate). 3. Small changes in SFEMG were seen at three hours and three days after an exposure sufficient to cause a reduction in red cell acetyl cholinesterase to 60% of normal. The SFEMG changes were not accompanied by any clinical neuromuscular symptoms or signs and returned to normal 2 years after exposure. 4. The results indicate that there are reversible subclinical changes compatible with the development of non-depolarising NM block without frank clinical expression. In the small population examined there were individual variations in response which may reflect differences in safety margin at the neuromuscular junction. PMID:8735458

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

    PubMed

    Castellani, John W; Young, Andrew J

    2016-04-01

    Cold exposure in humans causes specific acute and chronic physiological responses. This paper will review both the acute and long-term physiological responses and external factors that impact these physiological responses. Acute physiological responses to cold exposure include cutaneous vasoconstriction and shivering thermogenesis which, respectively, decrease heat loss and increase metabolic heat production. Vasoconstriction is elicited through reflex and local cooling. In combination, vasoconstriction and shivering operate to maintain thermal balance when the body is losing heat. Factors (anthropometry, sex, race, fitness, thermoregulatory fatigue) that influence the acute physiological responses to cold exposure are also reviewed. The physiological responses to chronic cold exposure, also known as cold acclimation/acclimatization, are also presented. Three primary patterns of cold acclimatization have been observed, a) habituation, b) metabolic adjustment, and c) insulative adjustment. Habituation is characterized by physiological adjustments in which the response is attenuated compared to an unacclimatized state. Metabolic acclimatization is characterized by an increased thermogenesis, whereas insulative acclimatization is characterized by enhancing the mechanisms that conserve body heat. The pattern of acclimatization is dependent on changes in skin and core temperature and the exposure duration. PMID:26924539

  13. Acute eosinophilic pneumonia associated with glyphosate-surfactant exposure.

    PubMed

    De Raadt, Wanda M; Wijnen, Petal A; Bast, Aalt; Bekers, Otto; Drent, Marjolein

    2015-01-01

    We report a case of a female patient who developed acute eosinophilic pneumonia (AEP) after recent onset of smoking and exposure to glyphosate-surfactant.The additional exposure associated with the recent start of smoking may have contributed to the development and/or severity of AEP.A clinical relapse after re-challenge four years later both with smoking and glyphosate-surfactant made the association highly likely.Respiratory distress is a factor of poor outcome and mortality after ingestion of glyphosate-surfactant.This case highlights the importance of a thorough exposure history e.g., possible occupational and environmental exposures together with drug-intake.Genotyping should be considered in cases of severe unexplained pulmonary damage. PMID:26278698

  14. Neurobehavioral effects of acute styrene exposure in fiberglass boatbuilders

    SciTech Connect

    Letz, R.; Mahoney, F.C.; Hershman, D.L.; Woskie, S.; Smith, T.J. )

    1990-11-01

    A field investigation of the effects of acute exposure to styrene among fiberglass boatbuilders was performed. Personal samples of styrene in breathing zone air and postshift urinary mandelic acid were collected for 105 workers exposed and not exposed to styrene in 6 fiberglass boatbuilding companies in New England. Three tests from the computerized Neurobehavioral Evaluation System (NES) were performed by the subjects in the morning before exposure to styrene, near midday, and at the end of the work day. Duration of exposure averaged 2.9 years (SD = 4.6), 8-hour TWA styrene exposure averaged 29.9 ppm (SD = 36.2), and urinary mandelic acid averaged 347 mg/g creatinine (SD = 465). Regression analyses indicated a statistically significant relationship between postshift performance on the Symbol-Digit test and both acute styrene exposure and mandelic acid. Other analyses comparing workers exposed to less than 50 ppm and greater than 50 ppm styrene also showed a significant effect on Symbol-Digit performance. All three NES tests showed test-retest correlation coefficients above .80, and ease of use for collection of neurobehavioral data under field conditions was demonstrated.

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

    PubMed

    Epelman, Slava; Hamilton, Douglas R

    2006-02-01

    The United States Government has recently refocused their space program on manned missions to the Moon by 2018 and later to Mars. While there are many potential risks associated with exploration-class missions, one of the most serious and unpredictable is the effect of acute space radiation exposure, and the space program must make every reasonable effort to mitigate this risk. The two cosmic sources of radiation that could impact a mission outside the Earth's magnetic field are solar particle events (SPE) and galactic cosmic radiation (GCR). Either can cause acute and chronic medical illness. Numerous researchers are currently examining the ability of GCR exposure to induce the development of genetic changes that lead to malignancies and other delayed effects. However, relatively little has been published on the medical management of an acute SPE event and the potential impact on the mission and crew. This review paper will provide the readers with medical management options for an acute radiation event based on recommendations from the Department of Homeland Security (DHS), Centers for Disease Control (CDC), and evidence-based critical analysis of the scientific literature. It is the goal of this paper to stimulate debate regarding the definition of safety parameters for exploration-class missions to determine the level of medical care necessary to provide for the crew that will undertake such missions. PMID:16491581

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

    PubMed Central

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

    2008-01-01

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

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

    PubMed

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

    2006-04-01

    Recent studies have indicated that acute exposure to low level radiofrequency (RF) electromagnetic fields generated by mobile phones affects human cognition. However, the relatively small samples used, in addition to methodological problems, make the outcomes of these studies difficult to interpret. In our study we tested a large sample of volunteers (168) using a series of cognitive tasks apparently sensitive to RF exposure (a simple reaction task, a vigilance task, and a subtraction task). Participants performed those tasks twice, in two different sessions. In one session they were exposed to RFs, with half of subjects exposed to GSM signals and the other half exposed to CW signals, while in the other session they were exposed to sham signals. No significant effects of RF exposure on performance for either GSM or CW were found, independent of whether the phone was positioned on the left or on the right side. PMID:16304701

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

    SciTech Connect

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

    1985-04-01

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

  19. Acute disaster exposure and mental health complaints of Norwegian tsunami survivors six months post disaster.

    PubMed

    Heir, Trond; Weisaeth, Lars

    2008-01-01

    The objective was to investigate the relationship between possible disaster stressors and subsequent health problems among tourists experiencing the 2004 South-East Asia tsunami. A cross-sectional study was performed as a postal survey concerning the experiences of the disaster exposure in retrospect and the presence of psychological symptoms (GHQ-28) in Norwegian tsunami victims 6 months post disaster. The strongest predictors of health complaints were danger of death, witness impressions, and bereavements. Aggravated outcomes were also seen in those who helped others in the acute phase or had sole responsibility for children when the tsunami struck. Having a family member or close friend who was injured was reversely associated with health problems. Women reported more psychological distress than men, but the difference disappeared with increasing degree of danger exposure. Dose-response relationships to psychological distress were found for single exposure factors as well as for the cumulative effects of being exposed to several exposure variables. PMID:18834277

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

    PubMed Central

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

    2016-01-01

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

  1. Human Physiological Responses to Acute and Chronic Cold Exposure

    NASA Technical Reports Server (NTRS)

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

    2001-01-01

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

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

    SciTech Connect

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

    1991-03-11

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

  3. Mitigation Strategies for Acute Radiation Exposure during Space Flight

    NASA Technical Reports Server (NTRS)

    Hamilton, Douglas R.; Epelman, Slava

    2006-01-01

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

  4. Mitigation Strategies for Acute Radiation Exposure during Space Flight

    NASA Technical Reports Server (NTRS)

    Hamilton, Douglas R.; Epelman, Slava

    2006-01-01

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

  5. Psychological symptoms and intermittent hypertension following acute microwave exposure

    SciTech Connect

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

    1982-11-01

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

  6. Increased oxidative stress following acute and chronic high altitude exposure.

    PubMed

    Jefferson, J Ashley; Simoni, Jan; Escudero, Elizabeth; Hurtado, Maria-Elena; Swenson, Erik R; Wesson, Donald E; Schreiner, George F; Schoene, Robert B; Johnson, Richard J; Hurtado, Abdias

    2004-01-01

    The generation of reactive oxygen species is typically associated with hyperoxia and ischemia reperfusion. Recent evidence has suggested that increased oxidative stress may occur with hypoxia. We hypothesized that oxidative stress would be increased in subjects exposed to high altitude hypoxia. We studied 28 control subjects living in Lima, Peru (sea level), at baseline and following 48 h exposure to high altitude (4300 m). To assess the effects of chronic altitude exposure, we studied 25 adult males resident in Cerro de Pasco, Peru (altitude 4300 m). We also studied 27 subjects living in Cerro de Pasco who develop excessive erythrocytosis (hematocrit > 65%) and chronic mountain sickness. Acute high altitude exposure led to increased urinary F(2)-isoprostane, 8-iso PGF(2 alpha) (1.31 +/- 0.8 microg/g creatinine versus 2.15 +/- 1.1, p = 0.001) and plasma total glutathione (1.29 +/- 0.10 micromol versus 1.37 +/- 0.09, p = 0.002), with a trend to increased plasma thiobarbituric acid reactive substance (TBARS) (59.7 +/- 36 pmol/mg protein versus 63.8 +/- 27, p = NS). High altitude residents had significantly elevated levels of urinary 8-iso PGF(2 alpha) (1.3 +/- 0.8 microg/g creatinine versus 4.1 +/- 3.4, p = 0.007), plasma TBARS (59.7 +/- 36 pmol/mg protein versus 85 +/- 28, p = 0.008), and plasma total glutathione (1.29 +/- 0.10 micromol versus 1.55 +/- 0.19, p < 0.0001) compared to sea level. High altitude residents with excessive erythrocytosis had higher levels of oxidative stress compared to high altitude residents with normal hematological adaptation. In conclusion, oxidative stress is increased following both acute exposure to high altitude without exercise and with chronic residence at high altitude. PMID:15072717

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

    PubMed

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

    2015-11-01

    Limited information is available on the presence of microplastics in freshwater systems, and even less is known about the toxicological implications of the exposure of aquatic organisms to plastic particles. The present study was conducted to evaluate the effects of microplastic ingestion on the freshwater amphipod, Hyalella azteca. Hyalella azteca was exposed to fluorescent polyethylene microplastic particles and polypropylene microplastic fibers in individual 250-mL chambers to determine 10-d mortality. In acute bioassays, polypropylene microplastic fibers were significantly more toxic than polyethylene microplastic particles; 10-d lethal concentration 50% values for polyethylene microplastic particles and polypropylene microplastic fibers were 4.64 × 10(4) microplastics/mL and 71.43 microplastics/mL, respectively. A 42-d chronic bioassay using polyethylene microplastic particles was conducted to quantify effects on reproduction, growth, and egestion. Chronic exposure to polyethylene microplastic particles significantly decreased growth and reproduction at the low and intermediate exposure concentrations. During acute exposures to polyethylene microplastic particles, the egestion times did not significantly differ from the egestion of normal food materials in the control; egestion times for polypropylene microplastic fibers were significantly slower than the egestion of food materials in the control. Amphipods exposed to polypropylene microplastic fibers also had significantly less growth. The greater toxicity of microplastic fibers than microplastic particles corresponded with longer residence times for the fibers in the gut. The difference in residence time might have affected the ability to process food, resulting in an energetic effect reflected in sublethal endpoints. PMID:26042578

  8. Pediatric Acute Lymphoblastic Leukemia and Exposure to Pesticides

    PubMed Central

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

    2013-01-01

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

  9. Acute neurological symptoms during hypobaric exposure: consider cerebral air embolism.

    PubMed

    Weenink, Robert P; Hollmann, Markus W; van Hulst, Robert A

    2012-11-01

    Cerebral arterial gas embolism (CAGE) is well known as a complication of invasive medical procedures and as a risk in diving and submarine escape. In the underwater environment, CAGE is caused by trapped air, which expands and leads to lung vessel rupture when ambient pressure decreases during ascent. Pressure decrease also occurs during hypobaric activities such as flying and, therefore, CAGE may theoretically be a risk in hypobaric exposure. We reviewed the available literature on this subject. Identified were 12 cases of CAGE due to hypobaric exposure. Based on these cases, we discuss pathophysiology, diagnosis, and treatment of CAGE due to hypobaric exposure. The low and slow pressure decrease during most hypobaric activities (as opposed to diving) account for the low incidence of CAGE during these exposures and suggest that severe air trapping must be present to cause barotrauma. This is also suggested by the large prevalence of air filled cysts in the case reports reviewed. We recommend considering CAGE in all patients presenting with acute central neurological injury during or shortly after pressure decrease such as flying. A CT scan of head and chest should be performed in these patients. Treatment with hyperbaric oxygen therapy should be initiated as soon as possible in cases of proven or probable CAGE. PMID:23156097

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

    PubMed

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

    2013-02-01

    Previous studies have shown that secondhand smoke induces lung function impairment and increases proinflammatory cytokines. The aim of the present study was to evaluate the acute effects of secondhand smoke on airway acidification and airway oxidative stress in never-smokers. In a randomized controlled cross-over trial, 18 young healthy never-smokers were assessed at baseline and 0, 30, 60, 120, 180 and 240 min after one-hour secondhand smoke exposure at bar/restaurant levels. Exhaled NO and CO measurements, exhaled breath condensate collection (for pH, H(2)O(2) and NO(2)(-)/NO(3)(-) measurements) and spirometry were performed at all time-points. Secondhand smoke exposure induced increases in serum cotinine and exhaled CO that persisted until 240 min. Exhaled breath condensate pH decreased immediately after exposure (p < 0.001) and returned to baseline by 180 min, whereas H(2)O(2) increased at 120 min and remained increased at 240 min (p = 0.001). No changes in exhaled NO and NO(2)/NO(3) were observed, while decreases in FEV(1) (p < 0.001) and FEV(1)/FVC (p < 0.001) were observed after exposure and returned to baseline by 180 min. A 1-h exposure to secondhand smoke induced airway acidification and increased airway oxidative stress, accompanied by significant impairment of lung function. Despite the reversal in EBC pH and lung function, airway oxidative stress remained increased 4 h after the exposure. Clinical trial registration number (EudraCT): 2009-013545-28. PMID:23218453

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

    PubMed Central

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

    2015-01-01

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

  12. Maresin-1 reduces airway inflammation associated with acute and repetitive exposures to organic dust.

    PubMed

    Nordgren, Tara M; Bauer, Christopher D; Heires, Art J; Poole, Jill A; Wyatt, Todd A; West, William W; Romberger, Debra J

    2015-07-01

    Agriculture industry workers are at a higher risk for chronic bronchitis and obstructive pulmonary diseases, and current therapeutics are not entirely effective. We previously found that the specialized proresolving lipid mediator maresin-1 (MaR1) reduced proinflammatory cytokine release and intracellular adhesion molecule-1 (ICAM-1) expression in bronchial epithelial cells exposed to extracts of organic dust (DE) derived from swine confinement facilities in vitro. The objective of this study was to determine whether MaR1 is effective at limiting lung inflammation associated with acute and repetitive exposures to DE in an established murine model of inhalant dust exposures. C57Bl/6 mice were treated with MaR1 or vehicle control and intranasally instilled with DE once or daily for 3 weeks. Bronchioalveolar lavage fluid was analyzed for total and differential cell counts and proinflammatory cytokine levels, and lung tissues were assessed for histopathology and ICAM-1 expression. In both single and repetitive DE exposure studies, MaR1 significantly decreased bronchoalveolar lavage neutrophil infiltration, interleukin 6, tumor necrosis factor α, and chemokine C-X-C motif ligand 1 levels without altering repetitive DE-induced bronchioalveolar inflammation or lymphoid aggregate formation. Lung tissue ICAM-1 expression was also reduced in both single and repetitive exposure studies. These data suggest that MaR1 might contribute to an effective strategy to reduce airway inflammatory diseases induced by agricultural-related organic dust environmental exposures. PMID:25655838

  13. Acute mitochondrial dysfunction after blast exposure: potential role of mitochondrial glutamate oxaloacetate transaminase.

    PubMed

    Arun, Peethambaran; Abu-Taleb, Rania; Oguntayo, Samuel; Wang, Ying; Valiyaveettil, Manojkumar; Long, Joseph B; Nambiar, Madhusoodana P

    2013-10-01

    Use of improvised explosive devices has significantly increased the incidence of traumatic brain injury (TBI) and associated neuropsychiatric deficits in the recent wars in Iraq and Afghanistan. Acute deleterious effects of single and repeated blast exposure can lead to long-term neurobiological effects and neuropsychiatric deficits. Using in vitro and in vivo shock tube models of blast-induced TBI, we studied changes in mitochondrial energy metabolism after blast exposure. Single and repeated blast exposures in vitro resulted in significant decreases in neuronal adenosine triphosphate (ATP) levels at 6 h post-blast that returned towards normal levels by 24 h. Similar changes in ATP also were observed in the cerebral cortices of mice subjected to single and repeated blast exposures. In neurons, mitochondrial glutamate oxaloacetate transaminase (GOT2) plays a critical role in metabolism and energy production. Proteomic analysis of brain cortices showed a significant decrease in GOT2 levels 6 h after repeated blast exposures, which was further confirmed by Western blotting. Western blot analysis of GOT2 and pyruvate dehydrogenase in the cortex showed direct correlation only between GOT2 and ATP levels. Activity of GOT2 in the isolated cortical mitochondria also showed significant decrease at 6 h supporting the results of proteomic and Western blot analyses. Knowing the significant role of GOT2 in the neuronal mitochondrial energy metabolism, it is quite likely that the down regulation of GOT2 after blast exposure is playing a significant role in mitochondrial dysfunction after blast exposure. PMID:23600763

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

    EPA Science Inventory

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

  15. TWO ACUTE HUMAN POISONING CASES RESULTING FROM EXPOSURE TO DIAZINON TRANSFORMATION PRODUCTS IN EGYPT

    EPA Science Inventory

    Two spraymen working in public health occupations in Alexandria, Egypt, experienced acute toxicity resulting from exposure to diazinon. Symptomatology was similar to that previously reported for exposure to parathion or other organophosphorus insecticides. Plasma and red blood ce...

  16. Acute Eosinophilic Pneumonia: Pyrethroid Exposure & Change In Smoking Habit!

    PubMed

    Kuriakose, Kevin; Klair, Jagpal Singh; Johnsrud, Andrew; Meena, Nikhil K

    2016-06-01

    We report a case of Acute Eosinophilic Pneumonia (AEP) in a 29-year-old white woman with recent use of a'flea bomb' (containing pyrethroids) at home while remaining indoors, about 48 hours prior to presentation, and recent change in smoking habit (restarted 2 weeks prior after quitting for 10 years). She presented with two days of worsening fever, shortness of breath, productive cough, developed hypoxemic respiratory failure and ARDS. She required a PEEP of 20 and 100% FiO2 to maintain oxygenation. Bronchoalveolar lavage showed 36% Eosinophils. She was given IV steroids with dramatic clinical and radiological improvement. To the best of our knowledge, this is the second report associating AEP with pyrethroid exposure. PMID:27434983

  17. Acute health effects of accidental chlorine gas exposure

    PubMed Central

    2014-01-01

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

  18. Single exposure of dopamine D1 antagonist prevents and D2 antagonist attenuates methylphenidate effect

    PubMed Central

    Claussen, Catherine M; Witte, Lindsey J; Dafny, Nachum

    2015-01-01

    Methylphenidate (MPD) is a readily prescribed drug for the treatment of attention deficit hyperactivity disorder (ADHD) and moreover is used illicitly by youths for its cognitive-enhancing effects and recreation. MPD exposure in rodents elicits increased locomotor activity. Repetitive MPD exposure leads to further augmentation of their locomotor activity. This behavioral response is referred to as behavioral sensitization. Behavioral sensitization is used as an experimental marker for a drug’s ability to elicit dependence. There is evidence that dopamine (DA) is a key player in the acute and chronic MPD effect; however, the role of DA in the effects elicited by MPD is still debated. The objective of this study was to investigate the role of D1 and/or D2 DA receptors in the acute and chronic effect of MPD on locomotor activity. The study lasted for 12 consecutive days. Seven groups of male Sprague Dawley® rats were used. A single D1 or D2 antagonist was given before and after acute and chronic MPD administration. Single injection of D1 DA antagonist was able to significantly attenuate the locomotor activity when given prior to the initial MPD exposure and after repetitive MPD exposure, while the D2 DA antagonist partially attenuated the locomotor activity only when given before the second MPD exposure. The results show the role, at least in part, of the D1 DA receptor in the mechanism of behavioral sensitization, whereas the D2 DA receptor only partially modulates the response to acute and chronic MPD. PMID:27186140

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

    SciTech Connect

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

    1996-06-01

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

  20. 75 FR 14153 - National Advisory Committee for Acute Exposure Guideline Levels for Hazardous Substances; Notice...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-24

    ...A meeting of the National Advisory Committee for Acute Exposure Guideline Levels for Hazardous Substances (NAC/AEGL Committee) will be held on April 13-15, 2010, in San Francisco, CA. At this meeting, the NAC/AEGL Committee will address, as time permits, the various aspects of the acute toxicity and the development of Acute Exposure Guideline Levels (AEGLs) for the following chemicals: 1,3-......

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

    PubMed Central

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

    2015-01-01

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

  2. Repeated Exposure to Conditioned Fear Stress Increases Anxiety and Delays Sleep Recovery Following Exposure to an Acute Traumatic Stressor

    PubMed Central

    Greenwood, Benjamin N.; Thompson, Robert S.; Opp, Mark R.; Fleshner, Monika

    2014-01-01

    Repeated stressor exposure can sensitize physiological responses to novel stressors and facilitate the development of stress-related psychiatric disorders including anxiety. Disruptions in diurnal rhythms of sleep–wake behavior accompany stress-related psychiatric disorders and could contribute to their development. Complex stressors that include fear-eliciting stimuli can be a component of repeated stress experienced by human beings, but whether exposure to repeated fear can prime the development of anxiety and sleep disturbances is unknown. In the current study, adult male F344 rats were exposed to either control conditions or repeated contextual fear conditioning for 22 days followed by exposure to no, mild (10), or severe (100) acute uncontrollable tail shock stress. Exposure to acute stress produced anxiety-like behavior as measured by a reduction in juvenile social exploration and exaggerated shock-elicited freezing in a novel context. Prior exposure to repeated fear enhanced anxiety-like behavior as measured by shock-elicited freezing, but did not alter social exploratory behavior. The potentiation of anxiety produced by prior repeated fear was temporary; exaggerated fear was present 1 day but not 4 days following acute stress. Interestingly, exposure to acute stress reduced rapid eye movement (REM) and non-REM (NREM) sleep during the hours immediately following acute stress. This initial reduction in sleep was followed by robust REM rebound and diurnal rhythm flattening of sleep/wake behavior. Prior repeated fear extended the acute stress-induced REM and NREM sleep loss, impaired REM rebound, and prolonged the flattening of the diurnal rhythm of NREM sleep following acute stressor exposure. These data suggest that impaired recovery of sleep/wake behavior following acute stress could contribute to the mechanisms by which a history of prior repeated stress increases vulnerability to subsequent novel stressors and stress-related disorders. PMID

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

    SciTech Connect

    Not Available

    1991-06-14

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

  4. Single-exposure color digital holography

    NASA Astrophysics Data System (ADS)

    Feng, Shaotong; Wang, Yanhui; Zhu, Zhuqing; Nie, Shouping

    2010-11-01

    In this paper, we report a method for color image reconstruction by recording only one single multi-wavelength hologram. In the recording process, three lasers of different wavelengths emitting in the red, green and blue regions are used for illuminating on the object and the object diffraction fields will arrive at the hologram plane simultaneously. Three reference beams with different spatial angles will interfere with the corresponding object diffraction fields on the hologram plane, respectively. Finally, a series of sub-holograms incoherently overlapped on the CCD to be recorded as a multi-wavelength hologram. Angular division multiplexing is employed to reference beams so that the spatial spectra of the multiple recordings will be separated in the Fourier plane. In the reconstruction process, the multi-wavelength hologram will be Fourier transformed into its Fourier plane, where the spatial spectra of different wavelengths are separated and can be easily extracted by employing frequency filtering. The extracted spectra are used to reconstruct the corresponding monochromatic complex amplitudes, which will be synthesized to reconstruct the color image. For singleexposure recording technique, it is convenient for applications on the real-time image processing fields. However, the quality of the reconstructed images is affected by speckle noise. How to improve the quality of the images needs for further research.

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

    SciTech Connect

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

    1993-05-01

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

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  7. Feasibility of single-incision laparoscopic cholecystectomy for acute cholecystitis

    PubMed Central

    Ikumoto, Taro; Yamagishi, Hidetsugu; Iwatate, Mineo; Sano, Yasushi; Kotaka, Masahito; Imai, Yasuo

    2015-01-01

    AIM: To assess the safety of single-incision laparoscopic cholecystectomy (SILC) for acute cholecystitis. METHODS: All patients who underwent SILC at Sano Hospital (Kobe, Japan) between January 2010 and December 2014 were included in this retrospective study. Clinical data related to patient characteristics and surgical outcomes were collected from medical records. The parameters for assessing the safety of the procedure included operative time, volume of blood loss, achievement of the critical view of safety, use of additional trocars, conversion to laparotomy, intraoperative and postoperative complications, and duration of postoperative hospital stay. Patient backgrounds were statistically compared between those with and without conversion to laparotomy. RESULTS: A total of 100 patients underwent SILC for acute cholecystitis during the period. Preoperative endoscopic treatment was performed for suspected choledocholithiasis in 41 patients (41%). The mean time from onset of acute cholecystitis was 7.7 d. According to the Updated Tokyo Guidelines (TG13) for the severity of cholecystitis, 86 and 14 patients had grade I and grade II acute cholecystitis, respectively. The mean operative time was 87.4 min. The mean estimated blood loss was 80.6 mL. The critical view of safety was obtained in 89 patients (89%). Conversion laparotomy was performed in 12 patients (12%). Postoperative complications of Clavien-Dindo grade III or greater were observed in 4 patients (4%). The mean duration of postoperative hospital stay was 5.7 d. Patients converted from SILC to laparotomy tended to have higher days after onset. CONCLUSION: SILC is feasible for acute cholecystitis; in addition, early surgical intervention may reduce the risk of laparotomy conversion. PMID:26722614

  8. Acute Exposure from RADON-222 and Aerosols in Drinking Water

    NASA Astrophysics Data System (ADS)

    Bernhardt, George Paul, IV

    Radon-222 in water is released when the water is aerated, such as during showering. As a result, a temporary burst of radon-222 can appear as a short term, or acute, exposure. This study looked at homes with radon-222 concentrations in water from 800 picocuries per liter (pCi/l) to 53,000 pCi/l to determine the buildup of radon gas in a bathroom during showering. Samples from the tap and drain, compared to determine the percentage of radon-222 released, showed that between 58% and 88% of radon-222 in the water was released. The resultant radon-222 increase in air, measured with a flow-through detector, ranged from 2 pCi/l to 114 pCi/l in bathrooms due to a 10 to 15 minute shower with water flow rates ranging from 3 l/min to 6 l/min. Significantly, these rates did not fall rapidly but stayed approximately the same for up to 15 minutes after the water flow ceased. In examining exposures, the true danger is in the radon-222 progeny rather than the radon itself. The progeny can be inhaled and deposited in the tracheobronchial passages in the lung. Filter samples of bathroom air measured in a portable alpha spectrometer showed an increase in radon-222 progeny, notably polonium-218 and -214, in the air after showering. These increases were gradual and were on the order of 0.5 pCi/l at the highest level. Tap samples measured in a portable liquid scintillator showed that the progeny are present in the water but are not in true secular equilibrium with the radon-222 in the water. Therefore, the radon-222 does not have to decay to produce progeny since the progeny are already present in the water. A two stage sampler was used to examine the percentage of radiation available in aerosols smaller than 7 microns. Repeated trials showed that up to 85% of the radiation available in the aerosols is contained in the smaller, more respirable particles.

  9. Studies of adaptive response and mutation induction in MCF-10A cells following exposure to chronic or acute ionizing radiation.

    PubMed

    Manesh, Sara Shakeri; Sangsuwan, Traimate; Wojcik, Andrzej; Haghdoost, Siamak

    2015-10-01

    A phenomenon in which exposure to a low adapting dose of radiation makes cells more resistant to the effects of a subsequent high dose exposure is termed radio-adaptive response. Adaptive response could hypothetically reduce the risk of late adverse effects of chronic or acute radiation exposures in humans. Understanding the underlying mechanisms of such responses is of relevance for radiation protection as well as for the clinical applications of radiation in medicine. However, due to the variability of responses depending on the model system and radiation condition, there is a need to further study under what conditions adaptive response can be induced. In this study, we analyzed if there is a dose rate dependence for the adapting dose, assuming that the adapting dose induces DNA response/repair pathways that are dose rate dependent. MCF-10A cells were exposed to a 50mGy adapting dose administered acutely (0.40Gy/min) or chronically (1.4mGy/h or 4.1mGy/h) and then irradiated by high acute challenging doses. The endpoints of study include clonogenic cell survival and mutation frequency at X-linked hprt locus. In another series of experiment, cells were exposed to 100mGy and 1Gy at different dose rates (acutely and chronically) and then the mutation frequencies were studied. Adaptive response was absent at the level of clonogenic survival. The mutation frequencies were significantly decreased in the cells pre-exposed to 50mGy at 1.4mGy/h followed by 1Gy acute exposure as challenging dose. Importantly, at single dose exposures (1 Gy or 100mGy), no differences at the level of mutation were found comparing different dose rates. PMID:26295444

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

    EPA Science Inventory

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

  11. ACUTE TRIETHYLTIN EXPOSURE: EFFECTS ON THE VISUAL EVOKED POTENTIAL AND HIPPOCAMPAL AFTERDISCHARGE

    EPA Science Inventory

    Acute administration of triethyltin (TET) produces a well-described sequence of pathological events characterized by intramyelinic vacuolation, edema, and histotoxic hypoxia. Recent behavioral studies have attempted to characterize the functional consequences of TET exposures. In...

  12. Acute Effects of Exposure to (56)Fe and (16)O Particles on Learning and Memory.

    PubMed

    Rabin, Bernard M; Poulose, Shibu M; Carrihill-Knoll, Kirsty L; Ramirez, Francisco; Bielinski, Donna F; Heroux, Nicholas; Shukitt-Hale, Barbara

    2015-08-01

    Although it has been shown that exposure to HZE particles disrupts cognitive performance when tested 2-4 weeks after irradiation, it has not been determined whether exposure to HZE particles acutely affects cognitive performance, i.e., within 4-48 h after exposure. The current experiments were designed to determine the acute effects of exposure to HZE particles ((16)O and (56)Fe) on cognitive performance and whether exposure to HZE particles affected learning or memory, as well as to understand the relationship between acute changes in the levels of NOX2 (a measure of oxidative stress) and COX2 (a measure of neuroinflammation) in specific brain regions and cognitive performance. The results of these studies indicate that the acute effects of radiation exposure on cognitive performance are on memory, not learning. Further, the acute effects of exposure to HZE particles on oxidative stress and neuroinflammation and their relationship to cognitive performance indicate that, although the effects of exposure to both (56)Fe and (16)O are widespread, only changes in specific regions of the brain may be related to changes in cognitive function. PMID:26207687

  13. Acute leukaemia after exposure to a weed killer, 2-methyl-4-chlorphenoxyacetic acid.

    PubMed

    Timonen, T T; Palva, I P

    1980-01-01

    Acute leukaemia is known to develop in many cases of benzene-induced pancytopenia [1]. This is a report of the development of acute leukaemia in a patient who had apparently recovered from pancytopenia after chronic exposure to a weed killer, 2-methyl-4-chlorphenoxyacetic acid. PMID:6769284

  14. Comparative long-term toxicity of Libby amphibole and amosite asbestos in rats after single or multiple intratracheal exposures.

    PubMed

    Cyphert, Jaime M; Carlin, Danielle J; Nyska, Abraham; Schladweiler, Mette C; Ledbetter, Allen D; Shannahan, Jonathan H; Kodavanti, Urmila P; Gavett, Stephen H

    2015-01-01

    In former mine workers of Libby, MT, exposure to amphibole-containing vermiculite was linked to increased rates of asbestosis, lung cancer, and mesothelioma. Although many studies showed adverse effects following exposure to Libby amphibole (LA; a mixture of winchite, richterite, and tremolite), little is known regarding the relative toxicity of LA compared to regulated asbestos, or regarding the risks associated with acute high-dose exposures relative to repeated low-dose exposures. In this study, pulmonary function, inflammation, and pathology were assessed after single or multiple intratracheal (IT) exposures of LA or a well-characterized amosite (AM) control fiber with equivalent fiber characteristics. Male F344 rats were exposed to an equivalent total mass dose (0.15, 0.5, 1.5, or 5 mg/rat) of LA or AM administered either as a single IT instillation, or as multiple IT instillations given every other week over a 13-wk period, and necropsied up to 20 mo after the initial IT. When comparing the two fiber types, in both studies LA resulted in greater acute neutrophilic inflammation and cellular toxicity than equal doses of AM, but long-term histopathological changes were approximately equivalent between fibers, suggesting that LA is at least as toxic as AM. In addition, although no dose-response relationship was discerned, mesothelioma or lung carcinomas were found after exposure to low and high dose levels of LA or AM in both studies. Conversely, when comparing studies, an equal mass dose given over multiple exposures instead of a single bolus resulted in greater chronic pathological changes in lung at lower doses, despite the initially weaker acute inflammatory response. Overall, these results suggest that there is a possibility of greater long-term pathological changes with repeated lower LA dose exposures, which more accurately simulates chronic environmental exposures. PMID:25506632

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

    PubMed Central

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

    2015-01-01

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

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

    PubMed

    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

  17. MEASUREMENTS OF CARDIOPULMONARY RESPONSE IN AWAKE RATS DURING ACUTE EXPOSURE TO NEAR AMBIENT CONCENTRATIONS OF OZONE

    EPA Science Inventory

    Although rodents are the most commonly studied animal species for ozone (O3) research, no acute cardiopulmonary function studies during exposure have been reported. wake Fischer-344 rats were exposed to )3 and response was evaluated before, during and after the exposure using a p...

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

    EPA Science Inventory

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

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

    EPA Science Inventory

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

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

    EPA Science Inventory

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

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

    EPA Science Inventory

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

  2. Preference for ethanol in zebrafish following a single exposure

    PubMed Central

    Mathur, Priya; Berberoglu, Michael; Guo, Su

    2012-01-01

    Ethanol is one of the most widely abused drugs in the world. Its addictive property is believed to primarily stem from its ability to influence the brain reinforcement pathway evolved for mediating natural rewards. Although dopamine is a known component of the reinforcement pathway, clear molecular and cellular compositions of this pathway and its sensitivity to ethanol remain not well understood. Zebrafish has been increasingly used to model and understand human disease states, due to its genetic tractability and ease of maintenance. In this study, we determine whether adult zebrafish develop ethanol preference after a single exposure using a conditioned place preference (CPP) paradigm. Moreover, we establish a procedure that can be carried out in an automated and relatively high-throughput fashion. We find that zebrafish of the AB strain display significantly increased preference for the compartment where they received ethanol during a single 20 -minute exposure. The largest increase in preference is in response to a 1.5% ethanol administered in the tank water. The results demonstrate robust ethanol preference in zebrafish. Such a relatively high-throughput assay with automated tracking and response to a single ethanol exposure provides a potential means for a large-scale screening aimed at understanding the brain reinforcement pathway and its sensitivity to ethanol in this genetically tractable vertebrate. PMID:20974186

  3. Lensless single-exposure super-resolved interferometric microscopy

    NASA Astrophysics Data System (ADS)

    Granero, Luis; Ferreira, Carlos; García, Javier; Micó, Vicente

    2013-04-01

    Single Exposure Super Resolved Interferometric Microscopy (SESRIM) has been recently proposed as a way to achieve one dimensional super resolved imaging in digital holographic microscopy. SESRIM uses Red-Green-Blue (RGB) multiplexing for illuminating the sample having different propagation angles for each one of the three illumination wavelengths and it has been experimentally validated considering color (A. Calabuig, V. Mico, J. Garcia, Z. Zalevsky, and C. Ferreira, "Single-exposure super-resolved interferometric microscopy by red-green-blue multiplexing," Opt. Lett. 36, 885-887, 2011) and monochrome (A. Calabuig, J. Garcia, C. Ferreira, Z. Zalevsky, and V. Mico, "Resolution improvement by single-exposure superresolved interferometric microscopy with a monochrome sensor," J. Opt. Soc. Am. A 28, 2346-2358, 2011) digital sensors for holographic recording. In this contribution, we will first review some of the characteristics of the previously reported SESRIM approaches and second, we will present preliminary results for the extension of SESRIM to the field of lensless holographic microscopy. Experimental results are reported validating this new kind of superresolution imaging method named as lensless SESRIM (L-SESRIM).

  4. Effects of Acutely Intermittent Hypoxic Exposure on Running Economy and Physical Performance in Basketball Players.

    PubMed

    Kilding, Andrew E; Dobson, Bryan P; Ikeda, Erika

    2016-07-01

    Kilding, AE, Dobson, BP, and Ikeda, E. Effects of acutely intermittent hypoxic exposure on running economy and physical performance in basketball players. J Strength Cond Res 30(7): 2033-2042, 2016-The aim of this study was to determine the effect of short duration intermittent hypoxic exposure (IHE) on physical performance in basketball players. Using a single-blind placebo-controlled group design, 14 trained basketball players were subjected to 15 days of passive short duration IHE (n = 7), or normoxic control (CON, n = 7), using a biofeedback nitrogen dilution device. A range of physiological, performance, and hematological variables were measured at baseline, and 10 days after IHE. After intervention, the IHE group, relative to the CON group, exhibited improvements in the Yo-Yo intermittent recovery level 1 (+4.8 ± 1.6%; effect size [ES]: 1.0 ± 0.4) and repeated high-intensity exercise test performance (-3.5 ± 1.6%; ES: -0.4 ± 0.2). Changes in hematological parameters were minimal, although soluble transferrin receptor increased after IHE (+9.2 ± 10.1%; ES: 0.3 ± 0.3). Running economy at 11 km·h (-9.0 ± 9.7%; ES: -0.7 ± 0.7) and 13 km·h was improved (-8.2 ± 6.9%; ES: -0.7 ± 0.5), but changes to V[Combining Dot Above]O2peak, HRpeak, and lactate were unclear. In summary, acutely IHE resulted in worthwhile changes in physical performance tests among competitive basketball players. However, physiological measures explaining the performance enhancement were in most part unclear. PMID:26677826

  5. Antiretroviral Therapies in Women after Single-Dose Nevirapine Exposure

    PubMed Central

    Lockman, S.; Hughes, M.D.; McIntyre, J.; Zheng, Y.; Chipato, T.; Conradie, F.; Sawe, F.; Asmelash, A.; Hosseinipour, M.C.; Mohapi, L.; Stringer, E.; Mngqibisa, R.; Siika, A.; Atwine, D.; Hakim, J.; Shaffer, D.; Kanyama, C.; Wools-Kaloustian, K.; Salata, R.A.; Hogg, E.; Alston-Smith, B.; Walawander, A.; Purcelle-Smith, E.; Eshleman, S.; Rooney, J.; Rahim, S.; Mellors, J.W.; Schooley, R.T.; Currier, J.S.

    2010-01-01

    BACKGROUND Peripartum administration of single-dose nevirapine reduces mother-to-child transmission of human immunodeficiency virus type 1 (HIV-1) but selects for nevirapine-resistant virus. METHODS In seven African countries, women infected with HIV-1 whose CD4+ T-cell counts were below 200 per cubic millimeter and who either had or had not taken single-dose nevirapine at least 6 months before enrollment were randomly assigned to receive antiretroviral therapy with tenofovir–emtricitabine plus nevirapine or tenofovir-emtricitabine plus lopinavir boosted by a low dose of ritonavir. The primary end point was the time to confirmed virologic failure or death. RESULTS A total of 241 women who had been exposed to single-dose nevirapine began the study treatments (121 received nevirapine and 120 received ritonavir-boosted lopinavir). Significantly more women in the nevirapine group reached the primary end point than in the ritonavir-boosted lopinavir group (26% vs. 8%) (adjusted P = 0.001). Virologic failure occurred in 37 (28 in the nevirapine group and 9 in the ritonavir-boosted lopinavir group), and 5 died without prior virologic failure (4 in the nevirapine group and 1 in the ritonavir-boosted lopinavir group). The group differences appeared to decrease as the interval between single-dose nevirapine exposure and the start of antiretroviral therapy increased. Retrospective bulk sequencing of baseline plasma samples showed nevirapine resistance in 33 of 239 women tested (14%). Among 500 women without prior exposure to single-dose nevirapine, 34 of 249 in the nevirapine group (14%) and 36 of 251 in the ritonavir-boosted lopinavir group (14%) had virologic failure or died. CONCLUSIONS In women with prior exposure to peripartum single-dose nevirapine (but not in those without prior exposure), ritonavir-boosted lopinavir plus tenofovir–emtricitabine was superior to nevirapine plus tenofovir–emtricitabine for initial antiretroviral therapy. (Funded by the National

  6. Single dose oral diclofenac for acute postoperative pain in adults

    PubMed Central

    Derry, Philip; Derry, Sheena; Moore, R Andrew; McQuay, Henry J

    2014-01-01

    Background Diclofenac is a non-steroidal anti-inflammatory drug (NSAID), available as a potassium salt (immediate-release) or sodium salt (delayed-release). This review updates an earlier review published in The Cochrane Database of Systematic Reviews (Issue 2, 2004) on ‘Single dose oral diclofenac for postoperative pain’. Objectives To assess single dose oral diclofenac for the treatment of acute postoperative pain. Search methods Cochrane CENTRAL, MEDLINE, EMBASE, Biological Abstracts, the Oxford Pain Relief Database, and reference lists of articles were searched; last search December 2008. Selection criteria Randomised, double-blind, placebo-controlled clinical trials of single dose, oral diclofenac (sodium or potassium) for acute postoperative pain in adults. Data collection and analysis Two review authors independently assessed studies for inclusion and quality, and extracted data. The area under the pain relief versus time curve was used to derive the proportion of participants with at least 50% pain relief over 4 to 6 hours, using validated equations. Relative benefit (risk) and number needed to treat to benefit (NNT) were calculated. Information on adverse events, time to remedication, and participants needing additional analgesia was also collected. Main results Fifteen studies (eight additional studies) with 1512 participants more than doubled the information available at each dose. Overall 50% to 60% of participants experienced at least 50% pain relief over 4 to 6 hours at any dose with diclofenac, compared to 10 to 20% with placebo, giving NNTs of about 2.5 for doses of 25 mg to 100 mg (similar to earlier review); no dose response was demonstrated. At 50 mg and 100 mg, NNTs for diclofenac potassium (2.1 (1.8 to 2.4) and 1.9 (1.7 to 2.2)) were significantly lower (better) than for diclofenac sodium (6.7 (4.2 to 17) and 4.5 (3.2 to 7.7)). The median time to use of rescue medication was 2 hours for placebo, 4.3 hours for diclofenac 50 mg and 4.9 hours

  7. Molecular and cellular profiling of acute responses to total body radiation exposure in ovariectomized female cynomolgus macaques

    PubMed Central

    DeBo, Ryne J.; Register, Thomas C.; Caudell, David L.; Sempowski, Gregory D.; Dugan, Gregory; Gray, Shauna; Owzar, Kouros; Jiang, Chen; Bourland, J. Daniel; Chao, Nelson J.; Cline, J. Mark

    2015-01-01

    Purpose The threat of radiation exposure requires a mechanistic understanding of radiation-induced immune injury and recovery. The study objective was to evaluate responses to ionizing radiation in ovariectomized (surgically post-menopausal) female cynomolgus macaques. Materials and methods Animals received a single total-body irradiation (TBI) exposure at doses of 0, 2 or 5 Gy with scheduled necropsies at 5 days, 8 weeks and 24 weeks post-exposure. Blood and lymphoid tissues were evaluated for morphologic, cellular, and molecular responses. Results Irradiated animals developed symptoms of acute hematopoietic syndrome, and reductions in thymus weight, thymopoiesis, and bone marrow cellularity. Acute, transient increases in plasma monocyte chemoattractant protein 1 (MCP-1) were observed in 5 Gy animals along with dose-dependent alterations in messenger ribonucleic acid (mRNA) signatures in thymus, spleen, and lymph node. Expression of T cell markers was lower in thymus and spleen, while expression of macrophage marker CD68 (cluster of differentiation 68) was relatively elevated in lymphoid tissues from irradiated animals. Conclusions Ovariectomized female macaques exposed to moderate doses of radiation experienced increased morbidity, including acute, dose-dependent alterations in systemic and tissue-specific biomarkers, and increased macrophage/T cell ratios. The effects on mortality exceeded expectations based on previous studies in males, warranting further investigation. PMID:25786585

  8. Persistence of the acute effects of ozone exposure

    SciTech Connect

    Folinsbee, L.J.; Horvath, S.M.

    1986-12-01

    Reexposure to ozone 24 h after an initial exposure results in greater decreases in forced expiratory tests of lung function following the second exposure. The purpose of this study was to determine whether this hyperresponsiveness was present earlier than 24 h or persisted beyond 24 h. Four groups of subjects (n = 6,6,7,7) were exposed to 0.25 ppm ozone and then reexposed at 12, 24, 48, or 72 h, respectively. During the 1-h exposures (Ta = 20 degrees C, RH = 70%) all subjects exercised continuously at approximately 65% of their respective peak VO2; VE averaged 63 L X min-1. The decrease in FEV1.0 after the second ozone exposure was significantly larger than that after the first for subjects reexposed at 12 or 24 h; FEV1.0 dropped 12% and 19% in the 12 h group, and 20% and 35% in the 24 h group. Subjects reexposed at 48 or 72 h had FEV1.0 responses which were not significantly different from the first exposure. Delta FEV1.0 on the first and second exposures were significantly correlated (r = 0.59). Symptoms generally paralleled changes in function. We conclude that the hyperresponsiveness to ozone following exposure to 0.25 ppm ozone under the conditions of this study is apparent within 12 h and is not present at 72 h.

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

    EPA Science Inventory

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

  10. Efficacy of multiple exposure with low level He-Ne laser dose on acute wound healing: a pre-clinical study

    NASA Astrophysics Data System (ADS)

    Prabhu, Vijendra; Rao, Bola Sadashiva S.; Mahato, Krishna Kishore

    2014-02-01

    Investigations on the use of Low Level Laser Therapy (LLLT) for wound healing especially with the red laser light have demonstrated its pro-healing potential on a variety of pre-clinical and surgical wounds. However, until now, in LLLT the effect of multiple exposure of low dose laser irradiation on acute wound healing on well-designed pre-clinical model is not much explored. The present study aimed to investigate the effect of multiple exposure of low dose Helium Neon laser on healing progression of full thickness excision wounds in Swiss albino mice. Further, the efficacy of the multiple exposure of low dose laser irradiation was compared with the single exposure of optimum dose. Full thickness excision wounds (circular) of 15 mm diameter were created, and subsequently illuminated with the multiple exposures (1, 2, 3, 4 and 5 exposure/ week until healing) of He-Ne (632.8 nm, 4.02 mWcm-2) laser at 0.5 Jcm-2 along with single exposure of optimum laser dose (2 J/cm-2) and un-illuminated controls. Classical biophysical parameters such as contraction kinetics, area under the curve and the mean healing time were documented as the assessment parameters to examine the efficacy of multiple exposures with low level laser dose. Experimental findings substantiated that either single or multiple exposures of 0.5 J/cm2 failed to produce any detectable alterations on wound contraction, area under the curve and mean healing time compared to single exposure of optimum dose (2 Jcm-2) and un-illuminated controls. Single exposure of optimum, laser dose was found to be ideal for acute wound healing.

  11. Evaluation of published single nucleotide polymorphisms associated with acute GVHD.

    PubMed

    Chien, Jason W; Zhang, Xinyi Cindy; Fan, Wenhong; Wang, Hongwei; Zhao, Lue Ping; Martin, Paul J; Storer, Barry E; Boeckh, Michael; Warren, Edus H; Hansen, John A

    2012-05-31

    Candidate genetic associations with acute GVHD (aGVHD) were evaluated with the use of genotyped and imputed single-nucleotide polymorphism data from genome-wide scans of 1298 allogeneic hematopoietic cell transplantation (HCT) donors and recipients. Of 40 previously reported candidate SNPs, 6 were successfully genotyped, and 10 were imputed and passed criteria for analysis. Patient and donor genotypes were assessed for association with grades IIb-IV and III-IV aGVHD, stratified by donor type, in univariate and multivariate allelic, recessive and dominant models. Use of imputed genotypes to replicate previous IL10 associations was validated. Similar to previous publications, the IL6 donor genotype for rs1800795 was associated with a 20%-50% increased risk for grade IIb-IV aGVHD after unrelated HCT in the allelic (adjusted P = .011) and recessive (adjusted P = .0013) models. The donor genotype was associated with a 60% increase in risk for grade III-IV aGVHD after related HCT (adjusted P = .028). Other associations were found for IL2, CTLA4, HPSE, and MTHFR but were inconsistent with original publications. These results illustrate the advantages of using imputed single-nucleotide polymorphism data in genetic analyses and demonstrate the importance of validation in genetic association studies. PMID:22282500

  12. Single dose oral ibuprofen for acute postoperative pain in adults

    PubMed Central

    Derry, Christopher J; Derry, Sheena; Moore, R Andrew; McQuay, Henry J

    2014-01-01

    Background This review updates a 1999 Cochrane review showing that ibuprofen at various doses was effective in postoperative pain in single dose studies designed to demonstrate analgesic efficacy. New studies have since been published. Ibuprofen is one of the most widely used non-steroidal anti-inflammatory (NSAID) analgesics both by prescription and as an over-the-counter medicine. Ibuprofen is used for acute and chronic painful conditions. Objectives To assess analgesic efficacy of ibuprofen in single oral doses for moderate and severe postoperative pain in adults. Search methods We searched Cochrane CENTRAL, MEDLINE, EMBASE and the Oxford Pain Relief Database for studies to May 2009. Selection criteria Randomised, double blind, placebo-controlled trials of single dose orally administered ibuprofen (any formulation) in adults with moderate to severe acute postoperative pain. Data collection and analysis Two review authors independently assessed trial quality and extracted data. Pain relief or pain intensity data were extracted and converted into the dichotomous outcome of number of participants with at least 50% pain relief over 4 to 6 hours, from which relative risk and number-needed-to-treat-to-benefit (NNT) were calculated. Numbers of participants using rescue medication over specified time periods, and time to use of rescue medication, were sought as additional measures of efficacy. Information on adverse events and withdrawals were collected. Main results Seventy-two studies compared ibuprofen and placebo (9186 participants). Studies were predominantly of high reporting quality, and the bulk of the information concerned ibuprofen 200 mg and 400 mg. For at least 50% pain relief compared with placebo the NNT for ibuprofen 200 mg (2690 participants) was 2.7 (2.5 to 3.0) and for ibuprofen 400 mg (6475 participants) it was 2.5 (2.4 to 2.6). The proportion with at least 50% pain relief was 46% with 200 mg and 54% with 400 mg. Remedication within 6 hours was less

  13. Serum Profiling of Rat Dermal Exposure to JP-8 Fuel Reveals an Acute-Phase Response.

    PubMed

    Larabee, Jason L; Hocker, James R; Cheung, John Y; Gallucci, Randle M; Hanas, Jay S

    2008-01-01

    ABSTRACT Dermal exposure to JP-8 petroleum jet fuel leads to toxicological responses in humans and rodents. Serum profiling is a molecular analysis of changes in the levels of serum proteins and other molecules in response to changes in physiology. This present study utilizes serum profiling approaches to examine biomolecular changes in the sera of rats exposed to dermal applications of JP-8 (jet propulsion fuel-8). Using gel electrophoresis and electrospray ionization (ESI) mass spectrometry (MS), levels of serum proteins as well as low-mass constituents were found to change after dermal exposures to JP-8. The serum protein levels altered included the acute-phase response proteins haptoglobin, ceruloplasmin, alpha(1)-inhibitor III, and apolipoprotein A-IV. Haptoglobin levels increased after a 1-day JP-8 dermal exposure and continued to increase through 7 days of exposure. Ceruloplasmin levels increased after 5 days of exposure. Serum alpha(1)-inhibitor III was reduced after a 1-day exposure and the depletion continued after 7 days of exposure. Apolipoprotein A-IV increased after a 1-day exposure and then returned to basal levels after 3- and 5-day exposures of JP-8. Levels of the acute-phase protein alpha(2)-macroglobulin were found to not vary over these time course studies. Using ESI-MS analysis directly on the sera from rats exposed to dermal JP-8, low-mass sera constituents were found to correlate with control (acetone) or JP-8 exposure. PMID:20020890

  14. Acute profound thrombocytopenia with second exposure to eptifibatide associated with a strong antibody reaction

    PubMed Central

    ATTAYA, SHARIFF; KANTHI, YOGENDRA; ASTER, RICHARD; MCCRAE, KEITH

    2015-01-01

    We present a case of eptifibatide-induced acute profound thrombocytopenia in a 64-year-old male receiving eptifibatide for the second time during percutaneous coronary intervention. Although rare, short and self-limited episodes of acute and profound thrombocytopenia have been associated with eptifibatide exposure. The thrombocytopenia is thought to be immune mediated, and assays are available to test for eptifibatide-induced platelet antibodies. PMID:19172524

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

    SciTech Connect

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

    1988-01-01

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

  16. Modifications of the input currents on VTA dopamine neurons following acute versus chronic cocaine exposure.

    PubMed

    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

  17. Cellular kinetics in the lungs of aging Fischer 344 rats after acute exposure to ozone.

    PubMed Central

    Vincent, R.; Adamson, I. Y.

    1995-01-01

    Lung repair in aging Fischer 344 male rats was investigated after an acute inhalation exposure to ozone. Adult (9-month-old) and senescent (24-month-old) rats were exposed to 0.8 ppm ozone for a single period of 6 hours, and thereafter studied over 5 days of recovery in clean air. The animals were given intraperitoneal injections of colchicine and [3H]thymidine, 4 hours and 1.5 hours before termination, respectively. The lungs were inflated with glutaraldehyde, and tissue samples were embedded in epoxy resin for electron microscopy, or in glycol methacrylate for light-microscopic autoradiography. Exposure to ozone produced epithelial injury in alveolar ducts and terminal bronchioles, later reflected by the transient increase in mitotic activity of nonciliated bronchiolar cells and alveolar type 2 cells. The increase in metaphase-arrested cells and [3H]thymidine-labeled cells in bronchioles followed similar time courses, ie, maximal at days 1.5 to 2, and subsiding by day 3. In the alveoli, type 1 cell necrosis was observed early after exposure (6 hours recovery), without notable structural changes in the interstitial and endothelial compartments. The increased mitotic activity in the alveolar septa was mostly due to proliferation of epithelial type 2 cells, which was maximal at day 1.5, and of interstitial cells, maximal at day 2.5. The magnitude of the mitotic responses of nonciliated bronchiolar cells, alveolar type 2 cells and interstitial cells was highest (+50%) in the lungs of senescent rats. Although the cellular events during repair are essentially similar in both age groups, the results indicate that senescent rats have a significantly higher level of initial injury from inhalation of ozone than adult animals. Images Figure 1 Figure 2 Figure 5 PMID:7717445

  18. The Acute Exposure Effects of Inhaled Nickel Nanoparticles on Murine Endothelial Progenitor Cells

    PubMed Central

    Liberda, Eric N; Cuevas, Azita K; Qu, Qingshan; Chen, Lung Chi

    2014-01-01

    Introduction The discovery of endothelial progenitor cells (EPCs) may help to explain observed cardiovascular effects associated with inhaled nickel nanoparticle exposures such as increases in vascular inflammation, generate reactive oxygen species, alter vasomotor tone, and potentiated atherosclerosis in murine species. Methods Following an acute whole body inhalation exposure to 500μg/m3 of nickel nanoparticles for 5 hrs, bone marrow EPCs from C57BL/6 mice were isolated. EPCs were harvested for their RNA or used in a variety of assays including chemotaxis, tube formation, and proliferation. Gene expression was assessed for important receptors involved in EPC mobilization and homing using RT-PCR methods. EPCs, circulating endothelial progenitor cells (CEPCs), circulating endothelial cells (CECs), and endothelial microparticles (EMPs) were quantified on a BD FACSCalibur to examine endothelial damage and repair associated with the exposure. Results and Conclusions Acute exposure to inhaled nickel nanoparticles significantly increased both bone marrow EPCs as well as their levels in circulation (CEPCs). CECs were significantly elevated indicating that endothelial damage occurred due to the exposure. There was no significant difference in EMPs between the two groups. Tube formation and chemotaxis, but not proliferation, of bone marrow EPCs was impaired in the nickel nanoparticle exposed group. These results coincided with a decrease in the mRNA of receptors involved in EPC mobilization and homing. This data provides new insight into how an acute nickel nanoparticle exposure to half of the current Occupational Safety & Health Administration permissible exposure limit may adversely affect EPCs. PMID:25144474

  19. Cognitive influences on health symptoms from acute chemical exposure.

    PubMed

    Dalton, P

    1999-11-01

    Symptom reports, perceived adverse health effects, and public health concerns are increasingly precipitated by the perception of chemical odors. This study examined the interaction between health cognitions, odor perception, and symptom reports. A group of 180 healthy men and women were exposed to 1 of 3 ambient odors, normatively rated as healthful (methyl salicylate, or wintergreen), harmful (butanol or alcohol), and ambiguous (isobomyl acetate, or balsam), after receiving 1 of 3 odorant characterizations (harmful, healthful, and neutral). Individuals given a harmful bias reported significantly more health symptoms following exposure and more intense odor and irritation during exposure than did those given a neutral or healthful bias. The overall pattern of results suggests that many of the health-related effects of exposure to odorants are mediated not by a direct agency of odors but by cognitive variables, such as mental models of the relationship between environmental odors and health. PMID:10619531

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

    PubMed

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

    2015-06-01

    The role of repeated exposure to collective trauma in explaining response to subsequent community-wide trauma is poorly understood. We examined the relationship between acute stress response to the 2013 Boston Marathon bombings and prior direct and indirect media-based exposure to three collective traumatic events: the September 11, 2001 (9/11) terrorist attacks, Superstorm Sandy, and the Sandy Hook Elementary School shooting. Representative samples of residents of metropolitan Boston (n = 846) and New York City (n = 941) completed Internet-based surveys shortly after the Boston Marathon bombings. Cumulative direct exposure and indirect exposure to prior community trauma and acute stress symptoms were assessed. Acute stress levels did not differ between Boston and New York metropolitan residents. Cumulative direct and indirect, live-media-based exposure to 9/11, Superstorm Sandy, and the Sandy Hook shooting were positively associated with acute stress responses in the covariate-adjusted model. People who experience multiple community-based traumas may be sensitized to the negative impact of subsequent events, especially in communities previously exposed to similar disasters. PMID:25896419

  1. Examining acute health outcomes due to ozone exposure and their subsequent relationship to chronic disease outcomes

    SciTech Connect

    Ostro, B.D.

    1993-12-01

    Current evidence indicates that individuals exposed to short term elevations in ambient ozone may experience both upper and lower respiratory effects. Some respiratory symptoms and spirometric changes are mild and reversible in nature, while others involve more severe outcomes, including hospital admissions and emergency room visits. However, many questions remain about the effects of acute ozone exposure and the implications of this exposure for chronic disease outcomes. For example, the identification of sensitive subgroups, the delineation of the entire spectrum of health effects due to exposure to ozone, the potential synergy between viral infections and ozone exposure, and the nature of adaptation to ozone are not well characterized. In addition, studies that examine the association between acute responses to ozone and potential biological indicators of a chronic disease process would be desirable. This paper serves to provide an overview of the types of epidemiologic studies that may be appropriate and factors to consider in addressing these questions. 23 refs.

  2. Developments in Dual-Energy Single-Exposure Chest Radiography.

    NASA Astrophysics Data System (ADS)

    Ho, Jung-Tsuoe

    1990-01-01

    Conventional chest radiography is the most commonly performed technique for the detection and diagnosis of lung cancer, which is the leading cause of cancer deaths in the United States. Nevertheless, a high percentage of cancer tumors are missed with this technique. One reason for errors is the overlap of tumor image with bone image in a chest radiograph. Dual-energy radiography has been suggested as the most effective method to eliminate bone contrast for better lung tumor visualization. Dual-energy radiography also provides a bone image from which benign nodules can be identified by the presence of nodule calcification. The purpose of this study is to evaluate the performance of a film-screen based dual-energy, single-exposure technique in lung nodule detection and to improve its performance by both hardware and software developments to increase the accuracy of lung cancer diagnosis. Our previous implementation of the technique resulted in small residual tissue contrast and incomplete tissue subtraction due to screen selection and x-ray beam hardening, respectively. Hardware developments, including uses of a new screen pair (Y_2O _2S/CaWO_4) and a K-edge filter (europium), were studied to improve residual tissue contrast by increasing the energy separation. As software developments, a three-dimensional interpolation algorithm and noise suppression methods were studied to achieve complete tissue subtraction and noise reduction, respectively. The results show that the Y_2O _2S/CaWO_4 performed better than LaOBr/CaWO_4; the use of K-edge filter produced more residual tissue contrast than that obtained without it; the interpolation algorithm effectively compensated for beam hardening and resulted in more complete tissue subtraction than image subtraction; and the noise suppression methods reduced noise by half. Even though the dual-exposure technique performed better than the single-exposure technique in a simulated lung nodule detection study, the difference between

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

    EPA Science Inventory

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

  4. HEALTH EFFECTS OF ACUTE EXPOSURE TO AIR POLLUTION

    EPA Science Inventory

    The investigators are among the first to investigate neurogenic inflammation in the lungs of rats exposed to whole diesel exhaust. It is anticipated that after exposure to both concentrations of diesel exhaust, consistently higher levels of plasma leakage and lower activity...

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

    EPA Science Inventory

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

  6. Cement dust exposure and acute lung function: A cross shift study

    PubMed Central

    2010-01-01

    Background Few studies have been carried out on acute effects of cement dust exposure. This study is conducted to investigate the associations between current "total" dust exposure and acute respiratory symptoms and respiratory function among cement factory workers. Methods A combined cross-sectional and cross-shift study was conducted in Dire Dawa cement factory in Ethiopia. 40 exposed production workers from the crusher and packing sections and 20 controls from the guards were included. Personal "total" dust was measured in the workers' breathing zone and peak expiratory flow (PEF) was measured for all selected workers before and after the shift. When the day shift ended, the acute respiratory symptoms experienced were scored and recorded on a five-point Likert scale using a modified respiratory symptom score questionnaire. Results The highest geometric mean dust exposure was found in the crusher section (38.6 mg/m3) followed by the packing section (18.5 mg/m3) and the guards (0.4 mg/m3). The highest prevalence of respiratory symptoms for the high exposed workers was stuffy nose (85%) followed by shortness of breath (47%) and "sneezing" (45%). PEF decreased significantly across the shift in the high exposed group. Multiple linear regression showed a significant negative association between the percentage cross-shift change in PEF and total dust exposure. The number of years of work in high-exposure sections and current smoking were also associated with cross-shift decrease in PEF. Conclusions Total cement dust exposure was related to acute respiratory symptoms and acute ventilatory effects. Implementing measures to control dust and providing adequate personal respiratory protective equipment for the production workers are highly recommended. PMID:20398255

  7. The effects of acute alcohol exposure on the response properties of neurons in visual cortex area 17 of cats

    SciTech Connect

    Chen Bo; Xia Jing; Li Guangxing; Zhou Yifeng

    2010-03-15

    Physiological and behavioral studies have demonstrated that a number of visual functions such as visual acuity, contrast sensitivity, and motion perception can be impaired by acute alcohol exposure. The orientation- and direction-selective responses of cells in primary visual cortex are thought to participate in the perception of form and motion. To investigate how orientation selectivity and direction selectivity of neurons are influenced by acute alcohol exposure in vivo, we used the extracellular single-unit recording technique to examine the response properties of neurons in primary visual cortex (A17) of adult cats. We found that alcohol reduces spontaneous activity, visual evoked unit responses, the signal-to-noise ratio, and orientation selectivity of A17 cells. In addition, small but detectable changes in both the preferred orientation/direction and the bandwidth of the orientation tuning curve of strongly orientation-biased A17 cells were observed after acute alcohol administration. Our findings may provide physiological evidence for some alcohol-related deficits in visual function observed in behavioral studies.

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

    NASA Technical Reports Server (NTRS)

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

    2007-01-01

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

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

    PubMed Central

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

    2010-01-01

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

  10. Acute Air Pollution Exposure and Risk of Suicide Completion

    PubMed Central

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

    2015-01-01

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

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

    EPA Science Inventory

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

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

    EPA Science Inventory

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

  13. COMPARISON OF THE RESPONSES OF CHILDREN AND ADULTS TO ACUTE OZONE EXPOSURE

    EPA Science Inventory

    The purpose of the paper is to compare the results of two studies in which the respiratory responses of children and adults to acute ozone (O3) exposure were measured. Forty-two 18-30 year old males were exposed for 2.5 hours in a controlled environmental chamber to either 0.0 or...

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

    EPA Science Inventory

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

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

    EPA Science Inventory

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

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

    EPA Science Inventory

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

  17. Single dose oral analgesics for acute postoperative pain in adults

    PubMed Central

    Moore, R Andrew; Derry, Sheena; McQuay, Henry J; Wiffen, Philip J

    2014-01-01

    Background Thirty-five Cochrane Reviews of randomised trials testing the analgesic efficacy of individual drug interventions in acute postoperative pain have been published. This overview brings together the results of all those reviews and assesses the reliability of available data. Objectives To summarise data from all Cochrane Reviews that have assessed the effects of pharmaceutical interventions for acute pain in adults with at least moderate pain following surgery, who have been given a single dose of oral analgesic taken alone. Methods We identified systematic reviews in The Cochrane Library through a simple search strategy. All reviews were overseen by a single Review Group, had a standard title, and had as their primary outcome numbers of participants with at least 50% pain relief over four to six hours compared with placebo. For individual reviews we extracted the number needed to treat (NNT) for this outcome for each drug/dose combination, and also the percentage of participants achieving at least 50% maximum pain relief, the mean of mean or median time to remedication, the percentage of participants remedicating by 6, 8, 12, or 24 hours, and results for participants experiencing at least one adverse event. Main results The overview included 35 separate Cochrane Reviews with 38 analyses of single dose oral analgesics tested in acute postoperative pain models, with results from about 45,000 participants studied in approximately 350 individual studies. The individual reviews included only high-quality trials of standardised design and outcome reporting. The reviews used standardised methods and reporting for both efficacy and harm. Event rates with placebo were consistent in larger data sets. No statistical comparison was undertaken. There were reviews but no trial data were available for acemetacin, meloxicam, nabumetone, nefopam, sulindac, tenoxicam, and tiaprofenic acid. Inadequate amounts of data were available for dexibuprofen, dextropropoxyphene 130

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

    PubMed Central

    Riley, Elizabeth; Kopotiyenko, Konstantin; Zhdanova, Irina

    2015-01-01

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

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

    PubMed

    Riley, Elizabeth; Kopotiyenko, Konstantin; Zhdanova, Irina

    2015-01-01

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

  20. Developmental mercury exposure elicits acute hippocampal cell death, reductions in neurogenesis, and severe learning deficits during puberty.

    PubMed

    Falluel-Morel, Anthony; Sokolowski, Katie; Sisti, Helene M; Zhou, Xiaofeng; Shors, Tracey J; Dicicco-Bloom, Emanuel

    2007-12-01

    Normal brain development requires coordinated regulation of several processes including proliferation, differentiation, and cell death. Multiple factors from endogenous and exogenous sources interact to elicit positive as well as negative regulation of these processes. In particular, the perinatal rat brain is highly vulnerable to specific developmental insults that produce later cognitive abnormalities. We used this model to examine the developmental effects of an exogenous factor of great concern, methylmercury (MeHg). Seven-day-old rats received a single injection of MeHg (5 microg/gbw). MeHg inhibited DNA synthesis by 44% and reduced levels of cyclins D1, D3, and E at 24 h in the hippocampus, but not the cerebellum. Toxicity was associated acutely with caspase-dependent programmed cell death. MeHg exposure led to reductions in hippocampal size (21%) and cell numbers 2 weeks later, especially in the granule cell layer (16%) and hilus (50%) of the dentate gyrus defined stereologically, suggesting that neurons might be particularly vulnerable. Consistent with this, perinatal exposure led to profound deficits in juvenile hippocampal-dependent learning during training on a spatial navigation task. In aggregate, these studies indicate that exposure to one dose of MeHg during the perinatal period acutely induces apoptotic cell death, which results in later deficits in hippocampal structure and function. PMID:17760861

  1. Acute crack cocaine exposure induces genetic damage in multiple organs of rats.

    PubMed

    Moretti, Eduardo Gregolin; Yujra, Veronica Quispe; Claudio, Samuel Rangel; Silva, Marcelo Jose Dias; Vilegas, Wagner; Pereira, Camilo Dias Seabra; de Oliveira, Flavia; Ribeiro, Daniel Araki

    2016-04-01

    Crack cocaine is a very toxic product derived from cocaine. The aim of this study was to evaluate genetic damage in multiple organs of rats following acute exposure to crack cocaine. A total of 20 Wistar rats were distributed into four groups (n = 5), as follows: 0, 4.5, 9, and 18 mg/kg body weight (b.w.) of crack cocaine administered by intraperitoneal route (i.p.). All animals were killed 24 h after intraperitoneal (i.p.) injection. The results showed that crack cocaine increased the number of micronucleated cells in bone marrow cells exposed to 18 mg/kg crack cocaine (p < 0.05). Peripheral blood and liver cells presented genetic damage as depicted by single cell gel (comet) assay at 9 and 18 mg/kg doses (p < 0.05). Immunohistochemistry data revealed significant increase in 8-hydroxy-20-deoxyguanosine (8-OHdG) immunoexpression in hepatocytes of animals exposed to crack cocaine at 9 and 18 mg/kg (p < 0.05) when compared with negative controls. Taken together, our results demonstrate that crack cocaine is able to induce genomic damage in multiple organs of Wistar rats. PMID:26825523

  2. Acute exposure to pure cylindrospermopsin results in oxidative stress and pathological alterations in tilapia (Oreochromis niloticus).

    PubMed

    Puerto, María; Jos, Angeles; Pichardo, Silvia; Moyano, Rosario; Blanco, Alfonso; Cameán, Ana M

    2014-04-01

    Cylindrospermopsin (CYN) is increasingly recognized as a potential threat to drinking water safety, due to its ubiquity. This cyanotoxin has been found to cause toxic effects in mammals, and although fish could be in contact with this toxin, acute toxicity studies on fish are nonexistent. This is the first study showing that single doses of CYN pure standard (200 or 400 μg CYN/kg fish bw) by oral route (gavage) generate histopathological effects in fish (Tilapia-Oreochromis niloticus) exposed to the toxin under laboratory condition. Among the morphological changes, disorganized parenchymal architecture in the liver, dilated Bowman's space in the kidney, fibrolysis in the heart, necrotic enteritis in the intestines, and hemorrhages in the gills, were observed. Moreover, some oxidative stress biomarkers in the liver and kidney of tilapias were altered. Thus, CYN exposure induced increased protein oxidation products in both organs, NADPH oxidase activity was significantly increased with the kidney being the most affected organ, and decreased GSH contents were also detected in both organs, at the higher dose assayed. PMID:22331699

  3. Single-exposure dual-energy computed radiography.

    PubMed

    Stewart, B K; Huang, H K

    1990-01-01

    This paper focuses on analysis and development of a single-exposure dual-energy digital radiographic method using computed radiography (Fuji FCR-101 storage phosphor system). A detector sandwich consisting of storage phosphor imaging plates and an interdetector filter is used. The goal of this process is to provide a simple dual-energy method using typical plane-projection radiographic equipment and techniques. This approach exploits the transparency of the storage phosphor plates, using radiographic information that would be otherwise lost, to provide energy selective information essentially as a by-product of the radiographic examination. In order to effectively make use of the large dynamic range of the storage phosphor imaging plates (10,000:1), a computed radiography image reading mode of fixed analog-to-digital converter gain and variable photomultiplier sensitivity provides image data which can be related to relative incident exposure for export to the decomposition algorithm. Scatter rejection requirements necessitated crossed 12:1 grids for a field size of 36 x 36 cm. Optimal technique parameters obtained from computer simulation through minimization of the aluminum and Plexiglas equivalent image uncertainty under conditions of constant absorbed does resulted as: 100 kVp using a 0.15-mm-thick tin (Sn) interdetector filter for the lung field. This yields a surface exposure of 23 mR and a surface absorbed dose of 0.26 mGy for a 23-cm-thick chest. Clinical application in evaluation of the solitary pulmonary nodule is discussed, along with an image set demonstrating this application. PMID:2233574

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

    PubMed

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

    2006-01-01

    Nitric oxide (NO) is a vasodilator that plays a role in blood flow and oxygen delivery. Acute hypoxia down regulates NO synthesis, a response that may exacerbate hypoxic stress by decreasing blood flow. This study was designed to test the hypotheses that pulmonary NO decreases upon acute exposure to high-altitude hypoxia and that relatively low levels of NO at altitude are associated with greater stress as reflected in more symptoms of acute mountain sickness (AMS). A sample of 47 healthy, adult, nonsmoking, sea-level residents provided measurements at sea level, at 2,800 m, and at 0-, 2-, and 3-h exposure times at 4,200 m altitude on Mauna Kea, Hawaii. Measurements were made of exhaled NO, oxygen saturation of hemoglobin, heart rate, and reported symptoms of AMS. The partial pressure of NO concentration in exhaled breath decreased significantly from a sea level mean of 4.2 nmHg to 3.8 nmHg at 2,800 m and 3.4 nmHg at 4,200 m. NO concentration in exhaled breath did not change significantly over a 3-h exposure at 4,200 m and recovered to pre-exposure baseline upon return to sea level. There was no significant association between the level of NO exhaled and the number of self-reported symptoms of AMS during this brief exposure. PMID:16493632

  5. Eruptive cherry angiomas and irritant symptoms after one acute exposure to the glycol ether solvent 2-butoxyethanol.

    PubMed

    Raymond, L W; Williford, L S; Burke, W A

    1998-12-01

    Seven clerical workers were evaluated in 1993, 8 months after exposure to vaporized 2-butoxyethanol (2-BE; also called butyl cellosolve or ethylene glycol monobutyl ether [EGMBE or EGBE]), which had been applied overnight to strip the floor of their file room. At the time of exposure, they had noted intense eye and respiratory irritation, marked dyspnea, nausea, and faintness, suggesting a concentration of 2-BE in the air of 200-300 parts per million (ppm). All seven workers later experienced recurrent eye and respiratory irritation, dry cough, and headache. Four months after the exposure, cherry angiomas began to appear on the arms, trunk, and thighs of six workers, who voiced concerns about the possibility of cancer. Our evaluation found no evidence of hematologic, liver, lung, or renal toxicity, but elevations in the erythrocyte sedimentation rate and blood pressure of each subject were found. Workplace air sampling found no detectable 2-BE, but traces (0.1-0.2 ppm) of formaldehyde were identified. Irritant symptoms abated after the group was moved to a room with better ventilation, and the mild hypertension gradually cleared, but new cherry angiomas have continued to appear 5 years after the acute exposure, as the initial ones persisted. These angiomas occur in healthy persons as they age but in this instance appear to have resulted from a single overexposure to 2-BE. We felt confident in reassuring the workers that they would suffer no serious consequences from this exposure. PMID:9871882

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

    PubMed Central

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

    2015-01-01

    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 anxiety-like behavior at both 24 h and 7 days post-ethanol exposure. At 24 h post-ethanol exposure, we observed increased excitability and decreased spontaneous inhibitory transmission (inhibitory postsynaptic currents, IPSCs) in the DR. At 7 days post-ethanol exposure, we observed increased spontaneous and miniature excitatory transmission (excitatory postsynaptic currents, EPSCs). Because acute ethanol alters GABA transmission in other brain regions, we assessed the effects of ex vivo ethanol (50 mM) on miniature IPSCs (mIPSCs) in the DR 24-h post-ethanol exposure. Bath application of ethanol enhanced the amplitude of mIPSCs in cells from ethanol-naive and chronic intermittent ethanol-exposed (CIE) mice, but significantly enhanced the frequency of mIPSCs only in cells from CIE mice, suggesting that DR neurons are more sensitive to the inhibitory effects of acute ethanol following CIE. On the basis of these findings, we hypothesize that net excitation of DR neurons following chronic ethanol exposure contributes to enhanced anxiety during ethanol withdrawal, and that increased sensitivity of DR neurons to subsequent ethanol exposure may mediate acute ethanol's ability to relieve anxiety during ethanol withdrawal. PMID:25120075

  7. Acute phase proteins in cattle after exposure to complex stress.

    PubMed

    Lomborg, S R; Nielsen, L R; Heegaard, P M H; Jacobsen, S

    2008-10-01

    Stressors such as weaning, mixing and transportation have been shown to lead to increased blood concentrations of acute phase proteins (APP), including serum amyloid A (SAA) and haptoglobin, in calves. This study was therefore undertaken to assess whether SAA and haptoglobin levels in blood mirror stress in adult cattle. Six clinically healthy Holstein cows and two Holstein heifers were transported for four to six hours to a research facility, where each animal was housed in solitary tie stalls. Blood samples for evaluation of leukocyte counts and serum SAA and haptoglobin concentrations were obtained before (0-sample) and at 8, 24 and 48 hours after the start of transportation. Upon arrival the animals gave the impression of being anxious, and they appeared to have difficulty coping with isolation and with being tied on the slippery floors of the research stable. Serum concentrations of SAA and haptoglobin increased significantly in response to the stressors (P < 0.01 and 0.05 at 48 hours, respectively). Additionally, the animals had transient neutrophilia at 8 and 24 hours (P < 0.05). In conclusion, the results of the study suggest that SAA and haptoglobin may serve as markers of stress in adult cattle. PMID:18461465

  8. Acute and Chronic Exposure to CO2 in Space Flight

    NASA Technical Reports Server (NTRS)

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

    2010-01-01

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

  9. Heterogeneity studies of hamster calcitonin following acute exposure to cigarette smoke: evidence for monomeric secretion.

    PubMed

    Tabassian, A R; Snider, R H; Nylen, E S; Cassidy, M; Becker, K L

    1993-05-01

    Various acute stimuli, including cigarette smoke, induce hypercalcitonemia in man and hamsters. We have shown that this occurs also in thyroidectomized subjects. In the present study we have further explored this phenomenon of secretion from the lungs by studying, simultaneously, the HPLC characteristics of pulmonary tissue and serum in control hamsters and in animals immediately following short-term exposure to cigarette smoke. In addition, we have studied the immunoheterogeneity of lung calcitonin 24 hours following the acute exposure. Control lungs contained monomeric immunoreactive calcitonin (M-iCT), high molecular mass iCT (H-iCT), and CT fragments. Immediately following smoke exposure, there was an acute decrease of lung iCT by radioimmunoassay (RIA) which consisted primarily of a decrease in M-iCT by HPLC. Simultaneously, the iCT increase in the serum by RIA was shown by HPLC to involve M-iCT. Twenty-four hours after smoke inhalation, the lung iCT by RIA and M-iCT by HPLC had returned towards control levels. These findings document the molecular characteristics of lung iCT following acute cigarette smoke stimulation, and suggest that under certain circumstances M-iCT may be actively secreted by the lung. It remains to be determined whether this type of secretion reflects hemocrine or paracrine release and what the physiological role for such a secretion may be. PMID:8507014

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

    SciTech Connect

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

    2012-04-15

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

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

    PubMed Central

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

    2011-01-01

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

  12. Ceftriaxone attenuates locomotor activity induced by acute and repeated cocaine exposure in mice.

    PubMed

    Tallarida, Christopher S; Corley, Gladys; Kovalevich, Jane; Yen, William; Langford, Dianne; Rawls, Scott M

    2013-11-27

    Ceftriaxone (CTX) decreases locomotor activation produced by initial cocaine exposure and attenuates development of behavioral sensitization produced by repeated cocaine exposure. An important question that has not yet been answered is whether or not CTX reduces behavioral sensitization to cocaine in cases in which the antibiotic is administered only during the period of cocaine absence that follows repeated cocaine exposure and precedes reintroduction to cocaine. We investigated this question using C57BL/6 mice. Mice pretreated with cocaine (15mg/kg×14 days) and then challenged with cocaine (15mg/kg) after 30 days of cocaine absence displayed sensitization of locomotor activity. For combination experiments, CTX injected during the 30 days of cocaine absence attenuated behavioral sensitization produced by cocaine challenge. In the case in which CTX was injected together with cocaine for 14 days, development of behavioral sensitization to cocaine challenge was also reduced. CTX attenuated the increase in locomotor activity produced by acute cocaine exposure; however, its efficacy was dependent on the dose of cocaine as inhibition was detected against 30mg/kg, but not 15mg/kg, of cocaine. These results from mice indicate that CTX attenuates locomotor activity produced by acute and repeated cocaine exposure and counters cocaine's locomotor activating properties in a paradigm in which the antibiotic is injected during the period of forced cocaine absence that follows repeated cocaine exposure. PMID:24120434

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

    PubMed Central

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

    2011-01-01

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

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

    PubMed

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

    2013-01-01

    The effect of the number of pesticide residue values below the LOQ/LOD of analytical methods, the variability of residues in individual fruits, mass of fruit units and the number of bootstrap iterations was studied on the probabilistically estimated acute exposure of consumers. The 4720 daily apple consumption data and the results of 1239 apple sample analyses for captan residues, performed within the Hungarian monitoring programme between 2005 and 2011, were used in this study as model matrix. Up to about 95th percentile exposure (µg/(kg bw·day)), simply multiplying each residue in composite samples with each consumption value gave similar estimates to those obtained with the complex procedure taking also into account the mass of and residues in individual fruits. However, the exposure above the 95th percentile calculated with the complex procedure gradually increased with increasing percentile level compared to the simple procedure. Including the high number of non-detects reduced the estimated exposure, which was the highest when only the residues measured in treated fruits were taken into account. The number of bootstrap iterations between 100 and 10,000 did not significantly affect the calculated exposure. The 99.99th percentile exposure amounted to 17.9% of the acute reference dose of 300 µg/(kg bw·day) for women of childbearing age. PMID:23742211

  15. Effects of Acute Exposures to Carbon Dioxide Upon Cognitive Functions

    NASA Technical Reports Server (NTRS)

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

    2016-01-01

    Large quantities of carbon dioxide (CO2) originate from human metabolism and typically, within spacecraft, remain about 10-fold higher in concentration than at the earth's surface. There have been recurring complaints by crew members of episodes of "mental viscosity" adversely affecting their performance, and there is evidence from the International Space Station (ISS) that associates CO2 levels with reports of headaches by crewmembers. Additionally, there is concern that CO2 may contribute to vision impairment and intracranial pressure that has been observed in some crewmembers. Consequently, flight rules have been employed to control the level of CO2 below 4 mm Hg, which is well below the existing Spacecraft Maximum Allowable Concentration (SMAC) of 10 mm Hg for 24-hour exposures, and 5.3 mm Hg for exposures of 7 to 180 days. However, the flight rule imposed limit, which places additional demands upon resources and current technology, still exceeds the lower bound of the threshold range for reportable headaches (2 - 5 mm Hg). Headaches, while sometime debilitating themselves, are also symptoms that can provide evidence that physiological defense mechanisms have been breached. The causes of the headaches may elicit other subtle adverse effects that occur at CO2 levels well below that for headaches. The concern that CO2 may have effects at levels below the threshold for headaches appears to be substantiated in unexpected findings that CO2 at concentrations below 2 mm Hg substantially reduced some cognitive functions that are associated with the ability to make complex decisions in conditions that are characterized by volatility, uncertainty, complexity, ambiguity, and delayed feedback. These are conditions that could be encountered by crews in off-nominal situations or during the first missions beyond low earth orbit. If findings of the earlier study are confirmed in crew-like subjects, our findings would provide additional evidence that CO2 may need to be

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

    PubMed

    Clarke, C

    2006-11-01

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

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

    PubMed

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

    2016-08-01

    Oxidative stress has been established as the key mechanism of the cochlear damage underlying noise-induced hearing loss, however, emerging evidence suggests that cochlear inflammation may also be a major contributor. This study aimed to improve our understanding of the cochlear inflammatory response associated with acute and chronic noise exposure. C57BL/6 mice were exposed to acute traumatic noise (100 dBSPL, 8-16 kHz for 24 h) and their cochleae collected at various intervals thereafter, up to 7 days. Using quantitative RT-PCR and immunohistochemistry, changes in expression levels of proinflammatory cytokines (TNF-α, IL-1β), chemokines (CCL2) and cell adhesion molecules (ICAM-1) were studied. All gene transcripts displayed similar dynamics of expression, with an early upregulation at 6 h post-exposure, followed by a second peak at 7 days. ICAM-1 immunoexpression increased significantly in the inferior region of the spiral ligament, peaking 24 h post-exposure. The early expression of proinflammatory mediators likely mediates the recruitment and extravasation of inflammatory cells into the noise-exposed cochlea. The occurrence of the latter expression peak is not clear, but it may be associated with reparative processes initiated in response to cochlear damage. Chronic exposure to moderate noise (90 dBSPL, 8-16 kHz, 2 h/day, up to 4 weeks) also elicited an inflammatory response, reaching a maximum after 2 weeks, suggesting that cochlear damage and hearing loss associated with chronic environmental noise exposure may be linked to inflammatory processes in the cochlea. This study thus provides further insight into the dynamics of the cochlear inflammatory response induced by exposure to acute and chronic noise. PMID:27109494

  18. Exposure to welding fumes is associated with acute systemic inflammatory responses

    PubMed Central

    Kim, J; Chen, J; Boyce, P; Christiani, D

    2005-01-01

    Aims: To investigate the acute systemic inflammatory response to welding fume exposure. Methods: Twenty four welders (42% smokers) and 13 non-exposed controls (23% smokers) were monitored at a welding school. Exposure to fine particulate matter (PM2.5) was assessed using cyclone samplers. Markers of systemic inflammation, including C-reactive protein (CRP), fibrinogen, and white blood cell (WBC) levels, were determined in peripheral blood samples collected at baseline and after 5.3 (SD 1.0) hours of exposure. Results: The median PM2.5 concentration for welders was 1.66 mg/m3, which was significantly greater than that for controls (0.04 mg/m3). Compared to non-smokers, smokers had a significantly higher baseline WBC count, but comparable levels of CRP and fibrinogen. In non-smokers, welding fume exposure was associated with a significant increase in WBC and neutrophil counts immediately following exposure (+0.8x103/µl, 95% CI 0.1 to 1.6, and +1.0x103/µl, 95% CI 0.4 to 1.7, respectively). A significant decrease in fibrinogen levels was observed in non-smokers (–32 mg/dl, 95% CI –63 to –1). No significant changes in WBC, neutrophil, and fibrinogen levels were found in smokers. Sixteen hours after welding exposure, CRP levels were found to be significantly increased in both non-smokers and smokers (0.90 mg/l, 95% CI 0.17 to 1.64). PM2.5 concentrations were found to be significantly associated with absolute neutrophil counts in non-smokers, and CRP levels in both non-smokers and smokers. Conclusions: High levels of welding fume exposure induce acute systemic inflammation in a relatively young, healthy working population. These results also suggest that smoking may modify the effect of welding fume exposure on specific inflammatory markers. PMID:15723880

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

    PubMed

    Marit, Jordan S; Weber, Lynn P

    2011-06-01

    While swimming endurance (critical swimming speed or U(crit)) and lipid stores have both been reported to acutely decrease after exposure to a variety of toxicants, the relationship between these endpoints has not been clearly established. In order to examine these relationships, adult zebrafish (Danio rerio) were aqueously exposed to solvent control (ethanol) or two nominal concentrations of 2,4-dinitrophenol (DNP), a mitochondrial electron transport chain uncoupler, for a 24-h period. Following exposure, fish were placed in a swim tunnel in clean water for swimming testing or euthanized immediately without testing, followed by analysis of whole body triglyceride levels. U(crit) decreased in both the 6 mg/L and 12 mg/L DNP groups, with 12 mg/L approaching the LC₅₀. A decrease in tail beat frequency was observed without a significant change in tail beat amplitude. In contrast, triglyceride levels were elevated in a concentration-dependent manner in the DNP exposure groups, but only in fish subjected to swimming tests. This increase in triglyceride stores may be due to a direct interference of DNP on lipid catabolism as well as increased triglyceride production when zebrafish were subjected to the co-stressors of swimming and toxicant exposure. Future studies should be directed at determining how acute DNP exposure combines with swimming to cause alterations in triglyceride accumulation. PMID:21406246

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

    USGS Publications Warehouse

    Bridges, C.M.

    1997-01-01

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

  1. Acute exposure to silica nanoparticles aggravate airway inflammation: different effects according to surface characteristics

    PubMed Central

    Park, Hye Jung; Sohn, Jung-Ho; Kim, Yoon-Ju; Park, Yoon Hee; Han, Heejae; Park, Kyung Hee; Lee, Kangtaek; Choi, Hoon; Um, Kiju; Choi, In-Hong; Park, Jung-Won; Lee, Jae-Hyun

    2015-01-01

    Silica nanoparticles (SNPs) are widely used in many scientific and industrial fields despite the lack of proper evaluation of their potential toxicity. This study examined the effects of acute exposure to SNPs, either alone or in conjunction with ovalbumin (OVA), by studying the respiratory systems in exposed mouse models. Three types of SNPs were used: spherical SNPs (S-SNPs), mesoporous SNPs (M-SNPs), and PEGylated SNPs (P-SNPs). In the acute SNP exposure model performed, 6-week-old BALB/c female mice were intranasally inoculated with SNPs for 3 consecutive days. In the OVA/SNPs asthma model, the mice were sensitized two times via the peritoneal route with OVA. Additionally, the mice endured OVA with or without SNP challenges intranasally. Acute SNP exposure induced significant airway inflammation and airway hyper-responsiveness, particularly in the S-SNP group. In OVA/SNPs asthma models, OVA with SNP-treated group showed significant airway inflammation, more than those treated with only OVA and without SNPs. In these models, the P-SNP group induced lower levels of inflammation on airways than both the S-SNP or M-SNP groups. Interleukin (IL)-5, IL-13, IL-1β and interferon-γ levels correlated with airway inflammation in the tested models, without statistical significance. In the mouse models studied, increased airway inflammation was associated with acute SNPs exposure, whether exposed solely to SNPs or SNPs in conjunction with OVA. P-SNPs appear to be relatively safer for clinical use than S-SNPs and M-SNPs, as determined by lower observed toxicity and airway system inflammation. PMID:26183169

  2. PULMONARY AND SYSTEMIC HEALTH EFFECTS OF ACUTE AND SUBCHRONIC EXPOSURE TO SMOKE OBSCURANT SGF-2

    EPA Science Inventory

    Sixty-day old, male rats were exposed to air, 0.5 or 1.5 ml/1 fog-oil for 3.5 hr/d, 4 days/wk for either 4 or 13 wk. Following the acute (4 wk) exposure to 1.5 mg/1, a multifocal pneumonitis was observed. Lung lavage fluid had an elevated number of polymorphonuclear leukocytes, a...

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

    USGS Publications Warehouse

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

    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.

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

    PubMed

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

    2016-05-01

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

  5. Study of in vivo exposure of single-walled carbon nanotubes in mouse liver

    NASA Astrophysics Data System (ADS)

    Lyons, Lyndon L.

    Currently, few studies are available that have explored the role of carbon nanoparticles in liver toxicity. The susceptibility of the liver to nanoparticles rises from the inhalation exposure route often encountered during manufacturing and occupational exposure. Persons occupying these types of environmental setting are exposed to airborne nanoparticles less than 100nm, which have unobstructed access to most area of the lungs due to their size. Several reports have shown that single walled carbon nanotubes (SWCNTs) induce oxidative stress and pose the greatest cytotoxicity potential do to their size. Also, studies in mice indicate nanoparticles tend to accumulate in organs such as the spleen, kidney and liver, which is a major concern due to a lack of knowledge as to their fate. Single Wall Carbon Nanotubes (SWCNT's) are able to more easily penetrate through the cell membrane and display higher cell toxicity than Multi walled carbon nanotubes (MWCTs), opening the possibility for crossing various biological barriers within the body. Therefore effective occupational and environmental health risk assessments are significant in controlling the manufacture process of carbon nanotubes (CNTs). The present study was undertaken to determine the toxicity exhibited by SWCNT in mouse liver tissue as a model system. Mouse exposure during inhalation with and without SWCNT and reactive oxygen species (ROS) products were measured by change in fluorescence using dichloro fluorescein (DCF). The result showed no increase ROS on exposure of SWCNT in a dose and time dependent manner. Also, there is no reduction levels of glutathione (GSH) and super oxide dismutase (SOD), the antioxidant protective mechanism present in mouse liver cells upon SWCNT exposure. Lipid Peroxidation (LPO) and Lactate Dehydrogenase (LDH) assays indicated no tissue or protein damage. Additionally, Caspases --8 and --3 assays were conducted in order to understand the apoptotic signaling pathways initiated by

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

    PubMed

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

    2015-11-15

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

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

    PubMed

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

    2016-03-01

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

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

    PubMed Central

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

    2015-01-01

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

  9. Chemosensory effects during acute exposure to N-methyl-2-pyrrolidone (NMP).

    PubMed

    van Thriel, Christoph; Blaszkewicz, Meinolf; Schäper, Michael; Juran, Stephanie A; Kleinbeck, Stefan; Kiesswetter, Ernst; Wrbitzky, Renate; Stache, Jürgen; Golka, Klaus; Bader, Michael

    2007-12-10

    Organic solvents are still essential in many industrial applications. To improve safety and health in the working environment lower occupational thresholds limits have been established and less toxic substitutes were introduced. N-Methyl-2-pyrrolidone (NMP) is a versatile solvent that is used as a substitute for dichloromethane in paint strippers. Due to conflicting results, there is a debate whether NMP causes irritations of the upper airways/eyes or not. In a human experimental study we examined the chemosensory effects of NMP under controlled conditions. Fifteen healthy males were investigated in a cross-over study. NMP vapor concentrations were 10, 40 and 80 mg/m(3) for 2 x 4h with an exposure-free lunch break of 30 min. To maximize chemosensory effects a peak exposure scenario (25mg/m(3) baseline, 160 mg/m(3) peaks 4 x 15 min, time-weighted average: 72 mg/m(3)) was tested. The four different conditions were conducted with and without moderate physical workload. Chemosensory effects were measured physiologically by anterior rhinomanometry, eye blink rate and breathing frequency. Subjectively, ratings of acute health symptoms and intensity of olfactory and trigeminal sensations were collected repeatedly throughout the exposures. All physiological variables were unaffected by the different NMP concentrations and even the peak exposures were non-effective on these measures. Olfactory mediated health symptoms increased dose-dependently. For these symptoms a strong adaptation was observable, especially during the first 4h of the exposures. Other acute symptoms were not significantly affected. Comparable to the symptoms, only olfactory sensations increased dose-dependently. Trigeminal sensations (e.g. eye and nose irritations) were evaluated as being barely detectable during the different exposures, only during 160 mg/m(3) exposure peak weak and transient eye irritation were reported. The results clearly suggest that NMP concentrations of up to 160 mg/m(3) caused no

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

    PubMed Central

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

    2016-01-01

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

  11. Acute acoustic trauma: dynamics of hearing loss following cessation of exposure.

    PubMed

    Segal, S; Harell, M; Shahar, A; Englender, M

    1988-07-01

    The natural history of individuals with acute acoustic trauma who ceased to be exposed to impact noise was examined. Retrospective follow-up was carried out for 4 years on patients who were qualified as disabled following acoustic trauma with permanent threshold shift. Eight hundred forty-one individuals (1682 ears) were examined, of which 1514 ears with acoustic trauma were included in the study group; 150 individuals (300 ears) who continued to be exposed to impact noise even after discovery of acoustic trauma comprised the control group. In the latter, as long as exposure to gunfire continued, the severity of acoustic trauma increased. In the study group, during the first year after injury, changes were observed in hearing, whether improvement or deterioration; after this period, hearing loss appeared to be final. We suggest that, after 1 year following acute acoustic trauma, the associated hearing loss be considered as final, provided there is no further exposure to noise. This finding holds great importance from the medicolegal standpoint, an aspect that is unclear in the literature. It clarifies that beyond the period of 1 year after initial exposure, the pathologic process ceases (as long as there is no additional exposure to noise or gunfire). Further hearing deterioration beyond this period is not related to the initial acoustic trauma but rather to other factors. PMID:3177612

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

    PubMed

    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

  13. Acute and repeated vapor exposure toxicology of 3-(methylthio)propionaldehyde.

    PubMed

    Ballantyne, B; Cawley, T J

    2000-12-01

    Because of its vapor pressure (0.6 torr at 20 C) there is a potential for vapor exposure to 3-(methylthio)propionaldehyde (3-MTP) vapor. Liquid 3-MTP may contain trace amounts of acrolein (up to 0.1%), and therefore acrolein vapor may also be present. Acute exposure (24 min to 4 h) of rats to substantially saturated atmospheres of 3-MTP generated statically (measured concentrations of 261-951 ppm) resulted in marked ocular and respiratory irritancy followed by death. Deaths occurred either during exposure or a few days postexposure, depending on exposure time. Measured acrolein vapor concentrations in these static studies were 16.7-216 ppm. In contrast, when substantially saturated vapor atmospheres were generated dynamically (277-320 ppm 3-MTP) only minor transient signs of irritancy were present, and only 1/40 exposed animals died. Acrolein vapor concentrations ranged 0-6.8 ppm. These findings indicate that the toxicity associated with acute static exposures to 3-MTP vapor was due to accumulated acrolein vapor, and that 3-MTP per se has a low order of acute vapor inhalation toxicity. In a first 9-d repeated vapor exposure study (6 h/d) rats were exposed to 0, 23.6, 96.8 or 246.2 ppm 3-MTP vapor; the mean acrolein concentration was 1.34 ppm (range 1.08-1.72 ppm). There were no mortalities, but exposure concentration-related indications of toxicity were present. These included reduced body weights, hematology (increased lymphocytes), serum chemistry (reduced total protein and globulin), and respiratory tract histopathology. The latter consisted mainly of squamous metaplasia in the anterior nasal passages at all concentrations, being minimal at 23.6 ppm. At the high concentration there was also olfactory atrophy and squamous metaplasia in the larynx, trachea, and larger bronchi; 23.6 ppm was a threshold effect level. The respiratory tract histopathology was compatible with exposure to acrolein vapor. In a second 9-d study, rats were exposed to 0, 0.47, 4.99 or 50

  14. Acute animal and human poisonings from cyanotoxin exposure - A review of the literature.

    PubMed

    Wood, Roslyn

    2016-05-01

    Cyanobacterial blooms are a potential health hazard due to the ability of some species to produce toxins that are harmful to other living organisms. This review provides a comprehensive summary of anecdotal and case reports on acute poisonings in animals and humans attributable to cyanotoxin exposure in fresh- and brackish-waters. Approximately two-thirds of reported poisonings have occurred in Europe and the United States. Dogs and livestock account for the majority of reported cases involving animal exposure to cyanotoxins, while recreational activities are responsible for approximately half of reported incidents involving human exposure. Due to data limitations it is difficult to estimate the total number of animals and humans affected by cyanotoxins, however, some general observations regarding frequency and numbers affected are made. The review demonstrates that cyanotoxins have, and will likely to continue to have, potentially serious consequences for public health and animal welfare worldwide. PMID:26995270

  15. Acute systemic exposure to silver-based nanoparticles induces hepatotoxicity and NLRP3-dependent inflammation.

    PubMed

    Ramadi, Khalil B; Mohamed, Yassir A; Al-Sbiei, Ashraf; Almarzooqi, Saeeda; Bashir, Ghada; Al Dhanhani, Aisha; Sarawathiamma, Dhanya; Qadri, Shahnaz; Yasin, Javed; Nemmar, Abderrahim; Fernandez-Cabezudo, Maria J; Haik, Yousef; Al-Ramadi, Basel K

    2016-10-01

    Nanoparticles (NPs) are increasingly being commercialized for use in biomedicine. NP toxicity following acute or chronic exposure has been described, but mechanistic insight into this process remains incomplete. Recent evidence from in vitro studies suggested a role for NLRP3 in NP cytotoxicity. In this study, we investigated the effect of systemic administration of composite inorganic NP, consisting of Ag:Cu:B (dose range 1-20 mg/kg), on the early acute (4-24 h post-exposure) and late phase response (96 h post-exposure) in normal and NLRP3-deficient mice. Our findings indicate that systemic exposure (≥2 mg/kg) was associated with acute liver injury due to preferential accumulation of NP in this organ and resulted in elevated AST, ALT and LDH levels. Moreover, within 24 h of NP administration, there was a dose-dependent increase in intraperitoneal neutrophil recruitment and upregulation in gene expression of several proinflammatory mediators, including TNF-α, IL-1β and S100A9. Histological analysis of liver tissue revealed evidence of dose-dependent hepatocyte necrosis, increase in sinusoidal Kupffer cells, lobular granulomas and foci of abscess formation which were most pronounced at 24 h following NP administration. NP deposition in the liver led to a significant upregulation in gene expression of S100A9, an endogenous danger signal recognition molecule of phagocytes, IL-1β and IL-6. The extent of proinflammatory cytokine activation and hepatotoxicity was significantly attenuated in mice deficient in the NLRP3 inflammasome, demonstrating the critical role of this innate immune system recognition receptor in the response to NP. PMID:26956548

  16. Acute exposure to selenium disrupts associative conditioning and long-term memory recall in honey bees (Apis mellifera).

    PubMed

    Burden, Christina M; Elmore, Christopher; Hladun, Kristen R; Trumble, John T; Smith, Brian H

    2016-05-01

    A plethora of toxic compounds - including pesticides, heavy metals, and metalloids - have been detected in honey bees (Apis mellifera) and their colonies. One such compound is selenium, which bees are exposed to by consuming nectar and pollen from flowers grown in contaminated areas. Though selenium is lethal at high concentrations, sublethal exposure may also impair honey bees' ability to function normally. Examining the effect of selenium exposure on learning and memory provides a sensitive assay with which to identify sublethal effects on honey bee health and behavior. To determine whether sublethal selenium exposure causes learning and memory deficits, we used proboscis extension reflex conditioning coupled with recall tests 30min and 24h post-conditioning. We exposed forager honey bees to a single sublethal dose of selenium, and 3h later we used an olfactory conditioning assay to train the bees to discriminate between one odor associated with sucrose-reinforcement and a second unreinforced odor. Following conditioning we tested short- and long-term recall of the task. Acute exposure to as little as 1.8ng of an inorganic form of selenium (sodium selenate) before conditioning caused a reduction in behavioral performance during conditioning. And, exposure to 18ng of either an inorganic form (sodium selenate) or an organic form (methylseleno-l-cysteine) of selenium caused a reduction in the bees' performance during the long-term recall test. These concentrations of selenium are lower than those found in the nectar of plants grown in selenium-contaminated soil, indicating that even low-grade selenium toxicity produces significant learning and memory impairments. This may reduce foragers' ability to effectively gather resources for the colony or nurse bees' ability to care for and maintain a healthy colony. PMID:26802564

  17. Comparative hazard identification by a single dose lung exposure of zinc oxide and silver nanomaterials in mice.

    PubMed

    Gosens, Ilse; Kermanizadeh, Ali; Jacobsen, Nicklas Raun; Lenz, Anke-Gabriele; Bokkers, Bas; de Jong, Wim H; Krystek, Petra; Tran, Lang; Stone, Vicki; Wallin, Håkan; Stoeger, Tobias; Cassee, Flemming R

    2015-01-01

    Comparative hazard identification of nanomaterials (NMs) can aid in the prioritisation for further toxicity testing. Here, we assessed the acute lung, systemic and liver responses in C57BL/6N mice for three NMs to provide a hazard ranking. A silver (Ag), non-functionalised zinc oxide (ZnO) and a triethoxycaprylylsilane functionalised ZnO NM suspended in water with 2% mouse serum were examined 24 hours following a single intratracheal instillation (I.T.). An acute pulmonary inflammation was noted (marked by a polymorphonuclear neutrophil influx) with cell damage (LDH and total protein) in broncho-alveolar lavage fluid (BALF) after administration of both non-functionalised and functionalised ZnO. The latter also induced systemic inflammation measured as an increase in blood neutrophils and a decrease in blood lymphocytes. Exposure to Ag NM was not accompanied by pulmonary inflammation or cytotoxicity, or by systemic inflammation. A decrease in glutathione levels was demonstrated in the liver following exposure to high doses of all three nanomaterials irrespective of any noticeable inflammatory or cytotoxic effects in the lung. By applying benchmark dose (BMD) modeling statistics to compare potencies of the NMs, we rank functionalised ZnO ranked the highest based on the largest number of affected endpoints, as well as the strongest responses observed after 24 hours. The non-functionalised ZnO NM gave an almost similar response, whereas Ag NM did not cause an acute response at similar doses. PMID:25966284

  18. Comparative Hazard Identification by a Single Dose Lung Exposure of Zinc Oxide and Silver Nanomaterials in Mice

    PubMed Central

    Gosens, Ilse; Kermanizadeh, Ali; Jacobsen, Nicklas Raun; Lenz, Anke-Gabriele; Bokkers, Bas; de Jong, Wim H.; Krystek, Petra; Tran, Lang; Stone, Vicki; Wallin, Håkan; Stoeger, Tobias; Cassee, Flemming R.

    2015-01-01

    Comparative hazard identification of nanomaterials (NMs) can aid in the prioritisation for further toxicity testing. Here, we assessed the acute lung, systemic and liver responses in C57BL/6N mice for three NMs to provide a hazard ranking. A silver (Ag), non-functionalised zinc oxide (ZnO) and a triethoxycaprylylsilane functionalised ZnO NM suspended in water with 2% mouse serum were examined 24 hours following a single intratracheal instillation (I.T.). An acute pulmonary inflammation was noted (marked by a polymorphonuclear neutrophil influx) with cell damage (LDH and total protein) in broncho-alveolar lavage fluid (BALF) after administration of both non-functionalised and functionalised ZnO. The latter also induced systemic inflammation measured as an increase in blood neutrophils and a decrease in blood lymphocytes. Exposure to Ag NM was not accompanied by pulmonary inflammation or cytotoxicity, or by systemic inflammation. A decrease in glutathione levels was demonstrated in the liver following exposure to high doses of all three nanomaterials irrespective of any noticeable inflammatory or cytotoxic effects in the lung. By applying benchmark dose (BMD) modeling statistics to compare potencies of the NMs, we rank functionalised ZnO ranked the highest based on the largest number of affected endpoints, as well as the strongest responses observed after 24 hours. The non-functionalised ZnO NM gave an almost similar response, whereas Ag NM did not cause an acute response at similar doses. PMID:25966284

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

    PubMed

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

    2016-06-01

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

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

    PubMed

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

    2016-01-01

    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

  1. Parameters of immunity acute phase reaction in men in relation to exposure duration to mercury vapours.

    PubMed

    Moszczynski, P; Moszczynski, P; Słowinski, S; Bem, S; Bartus, R

    1991-01-01

    The study was carried out in 89 men aged 21 to 57 years with a history of exposure to mercury vapour from 2 to 26 years during occupational work involving chlorine production by the method of mercury electrolysis. The workers were divided into three groups depending on the duration of occupational exposure: 1) 32 workers with a short history of exposure 2-10 years, 2) 37 workers with medium-long exposure - 11-20 years, and 3) 20 workers with a history of long exposure - 21-26 years. The urinary concentrations of mercury in these individuals was 73 +/- 60 microliters x 1(-1), and in blood this concentration was not exceeding 50 microliters x 1(-1). The control group comprised 40 men aged 17 to 52 years. They had not had any occupational exposure to chemicals, or harmful physical factors. On the basis of clinical, haematological and biochemical studies 89 workers with occupational exposure to mercury vapour were regarded as clinically healthy. None of them had any symptoms and signs of the complete neurasthenic syndrome or organic brain injury. Increased nervous excitability was the complaint of 24 workers, 9 had headaches, sleep disturbances were reported by 5, and a feeling of tiredness and apathy was mentioned by 5 men. EEG recording demonstrated 81 normal tracings, and moderately pathological records in 8 men. The parameters of immunity and proteins acute phase reaction were determined, measuring the concentration of immunoglobulins, lysozyme, C3c, C4, alpha 1-acid glycoprotein, haptoglobin and ceruloplasmin in serum. A lower level of IgA, IgG and lysozyme was only noted in individuals with occupational exposure exceeding 20 years.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1725175

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

    SciTech Connect

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

    2010-06-01

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

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

    PubMed Central

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

    2011-01-01

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

  4. Exposure to traffic pollution, acute inflammation and autonomic response in a panel of car commuters

    PubMed Central

    Sarnat, Jeremy A.; Golan, Rachel; Greenwald, Roby; Raysoni, Amit U.; Kewada, Priya; Winquist, Andrea; Sarnat, Stefanie E.; Flanders, W. Dana; Mirabelli, Maria C.; Zora, Jennifer E.; Bergin, Michael H.; Yip, Fuyuen

    2015-01-01

    Background Exposure to traffic pollution has been linked to numerous adverse health endpoints. Despite this, limited data examining traffic exposures during realistic commutes and acute response exists. Objectives: We conducted the Atlanta Commuters Exposures (ACE-1) Study, an extensive panel-based exposure and health study, to measure chemically-resolved in-vehicle exposures and corresponding changes in acute oxidative stress, lipid peroxidation, pulmonary and systemic inflammation and autonomic response. Methods We recruited 42 adults (21 with and 21 without asthma) to conduct two 2-h scripted highway commutes during morning rush hour in the metropolitan Atlanta area. A suite of in-vehicle particulate components were measured in the subjects’ private vehicles. Biomarker measurements were conducted before, during, and immediately after the commutes and in 3 hourly intervals after commutes. Results At measurement time points within 3 h after the commute, we observed mild to pronounced elevations relative to baseline in exhaled nitric oxide, C-reactive-protein, and exhaled malondialdehyde, indicative of pulmonary and systemic inflammation and oxidative stress initiation, as well as decreases relative to baseline levels in the time-domain heart-rate variability parameters, SDNN and rMSSD, indicative of autonomic dysfunction. We did not observe any detectable changes in lung function measurements (FEV1, FVC), the frequency-domain heart-rate variability parameter or other systemic biomarkers of vascular injury. Water soluble organic carbon was associated with changes in eNO at all post-commute time-points (p < 0.0001). Conclusions Our results point to measureable changes in pulmonary and autonomic biomarkers following a scripted 2-h highway commute. PMID:24906070

  5. The effects of acute pesticide exposure on neuroblastoma cells chronically exposed to diazinon.

    PubMed

    Axelrad, J C; Howard, C V; McLean, W G

    2003-03-14

    Speculation about potential neurotoxicity due to chronic exposure to low doses of organophosphate (OP) pesticides is not yet supported by experimental evidence. The objective of this work was to use a cell culture model of chronic OP exposure to determine if such exposure can alter the sensitivity of nerve cells to subsequent acute exposure to OPs or other compounds. NB2a neuroblastoma cells were grown in the presence of 25 microM diazinon for 8 weeks. The OP was then withdrawn and the cells were induced to differentiate in the presence of various other pesticides or herbicides, including OPs and OP-containing formulations. The resulting outgrowth of neurite-like structures was measured by light microscopy and quantitative image analysis and the IC(50) for each OP or formulation was calculated. The IC(50) values in diazinon-pre-exposed cells were compared with the equivalent values in cells not pre-exposed to diazinon. The IC(50) for inhibition of neurite outgrowth by acute application of diazinon, pyrethrum, glyphosate or a commercial formulation of glyphosate was decreased by between 20 and 90% after pre-treatment with diazinon. In contrast, the IC(50) for pirimiphos methyl was unaffected and those for phosmet or chlorpyrifos were increased by between 1.5- and 3-fold. Treatment of cells with chlorpyrifos or with a second glyphosate-containing formulation led to the formation of abnormal neurite-like structures in diazinon-pre-exposed cells. The data support the view that chronic exposure to an OP may reduce the threshold for toxicity of some, but by no means all, environmental agents. PMID:12505446

  6. Request for assistance in preventing vision disturbances and acute physical distress due to dimethylethylamine (DMEA) exposure

    SciTech Connect

    Not Available

    1987-12-01

    Methods were sought to reduce exposure to dimethylethylamine (DMEA) among foundry owners, operators, and workers and manufacturers of polyamides, due to possible vision disturbances and acute physical distress which may result. An investigation was made at an aluminum-casting foundry where blurring, fogging, and halo visual disturbances had been reported among workers exposed to DMEA, along with headaches, nausea, stomach pain, and increased heart rate. Medical and environmental studies were made. Exposure concentrations causing effects were measured at equal to or greater than 6 mg/cu m, or 2 parts per million (ppm), 8 hour time-weighted average. Exposures as high as 29 mg/cu m, (9.7 ppm) for 15 minutes also may have caused adverse effects. There was no current permissible exposure limit for DMEA. Leakage around pressure-tight seals in corebox machine gaskets may have accounted for some excessive exposure. It was recommended that more-frequent maintenance of these gaskets be undertaken along with other engineering controls. Work practices should be adjusted so as to reduce the pressure that delivers DMEA to coreboxes and to avoid excess gaseous DMEA in the corebox machine. Protective gloves should be worn. Evacuation plans should be developed in the event of a spill, leak, or other serious accident that may cause high concentrations of DMEA in the workplace.

  7. Effect of acute cold exposure on the mobilization of intramuscular glycogen and triglycerides in the rat.

    PubMed

    Górski, J; Kuryliszyn, A; Wereszczyńska, U

    1981-01-01

    Male Wistar rats, 300-360 g of body weight, were exposed to cold (1 degree) for 3 and 24 h. The levels of glycogen and triglycerides (TG) were estimated in "white" and "red" portions of the quadriceps muscle (FG and POG muscles respectively) in the soleus muscle (SO muscle), and in the heart muscle. It was found that 3 h cold exposure decreased significantly the glycogen level only in the heart muscle and had no effect in the other muscles examined. Exposure to cold for 24 h reduced the glycogen level in FG and FOG muscles, and lowered further the heart glycogen level. No change of glycogen level during cold exposure was observed in SO muscle. The level of TG in each examined muscle was significantly reduced already after 3 h of cold exposure. After 24 h it remained further unchanged in FG and FOG muscles whereas in SO and heart muscles a partial recovery of TG occurred. It is concluded that in warm-acclimatized rats the intramuscular TG play an important role as a local source of free fatty acids during the first period of acute exposure to cold. PMID:7348527

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

    PubMed Central

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

    2016-01-01

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

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

    PubMed

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

    2016-01-01

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

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

    PubMed Central

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

    2002-01-01

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

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

    NASA Technical Reports Server (NTRS)

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

    2011-01-01

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

  12. Association Between Extent of Thiazolidinedione Exposure and Risk of Acute Myocardial Infarction

    PubMed Central

    Dore, David D.; Trivedi, Amal N.; Mor, Vincent; Lapane, Kate L.

    2016-01-01

    Study Objectives To determine if an association exists between thiazolidinedione (rosiglitazone or pioglitazone) exposure and acute myocardial infarction, and if the timing of drug initiation relative to the onset of myocardial infarction affected the frequency of the event. Design Nested, case-control study. Data Source Health care claims from California, Florida, New York, Ohio, and Illinois from the Medicaid Analytic Extract database for calendar years 2001–2002. Patients Of patients who received metformin plus a sulfonylurea during a defined eligibility period, we identified 2316 cases who had a primary discharge diagnosis of acute myocardial infarction and 9700 controls, who were defined by means of risk-set sampling. Measurements and Main Results We reviewed demographic and clinical characteristics of the cases and controls, and documented initiation of thiazolidinedione therapy. We noted the time of therapy initiation within 180 days of the index date (date of acute myocardial infarction for cases, same date for matched controls) and assessed any association between the start of thiazolidinedione therapy and acute myocardial infarction, relative to use of metformin plus a sulfonylurea. We performed secondary analyses using various time intervals between start of thiazolidinedione and onset of event (0–90 and 91–180 days before the index date). Applying conditional logistic regression, we obtained adjusted odds ratios (AORs) and 95% confidence intervals (CIs). After adjustment for confounding, starting rosiglitazone (AOR 1.00, 95% CI 0.72–1.39) or pioglitazone (AOR 1.04, 95% CI 0.74–1.45) therapy in the 180 days before the index date was not associated with acute myocardial infarction. Point estimates for rosiglitazone (AOR 1.29, 95% CI 0.85–1.94) and, less so, pioglitazone (AOR 1.15, 95% CI 0.73–1.81) in the 90 days before the index date suggested a small increase in the rate of acute myocardial infarction shortly after the start of these drugs

  13. Haemodynamic changes in ipsilateral and contralateral fingers caused by acute exposures to hand transmitted vibration.

    PubMed Central

    Bovenzi, M; Griffin, M J

    1997-01-01

    OBJECTIVES: To investigate changes in digital circulation during and after exposure to hand transmitted vibration. By studying two frequencies and two magnitudes of vibration, to investigate the extent to which haemodynamic changes depend on the vibration frequency, the vibration acceleration, and the vibration velocity. METHODS: Finger skin temperature (FST), finger blood flow (FBF), and finger systolic pressure were measured in the fingers of both hands in eight healthy men. Indices of digital vasomotor tone-such as critical closing pressure and vascular resistance-were estimated by pressure-flow curves obtained with different hand heights. With a static load of 10 N, the right hand was exposed for 30 minutes to each of the following root mean squared (rms) acceleration magnitudes and frequencies of vertical vibration: 22 m.s-2 at 31.5 Hz, 22 m.s-2 at 125 Hz, and 87 m.s-2 at 125 Hz. A control condition consisted of exposure to the static load only. The measures of digital circulation and vasomotor tone were taken before exposure to the vibration and the static load, and at 0, 20, 40, and 60 minutes after the end of each exposure. RESULTS: Exposure to static load caused no significant changes in FST, FBF, or indices of vasomotor tone in either the vibrated right middle finger or the non-vibrated left middle finger. In both fingers, exposure to vibration of 125 Hz and 22 m.s-2 produced a greater reduction in FBF and a greater increase in vasomotor tone than did vibration of 31.5 Hz and 22 m.s-2. In the vibrated right finger, exposure to vibration of 125 Hz and 87 m.s-2 provoked an immediate vasodilation which was followed by vasoconstriction during recovery. The non-vibrated left finger showed a significant increase in vasomotor tone throughout the 60 minute period after the end of vibration exposure. CONCLUSIONS: The digital circulatory response to acute vibration depends upon the magnitude and frequency of the vibration stimulus. Vasomotor mechanisms, mediated

  14. Agricultural adjuvants: acute mortality and effects on population growth rate of Daphnia pulex after chronic exposure.

    PubMed

    Stark, John D; Walthall, William K

    2003-12-01

    Acute and chronic toxicity of eight agricultural adjuvants (Bond, Kinetic, Plyac, R-11, Silwet L-77, Sylgard 309, X-77, and WaterMaxx) to Daphnia pulex were evaluated with 48-h acute lethal concentration estimates (LC50) and a 10-d population growth-rate measurement, the instantaneous rate of increase (r1). Based on LC50, the order of toxicity was R-11 > X-77 = Sylgard 309 = Silwet L-77 > Kinetic > Bond > Plyac > WaterMaxx; all LC50 estimates were higher than the expected environmental concentration (EEC) of 0.79 mg/L, indicating that none of these adjuvants should cause high levels of mortality in wild D. pulex populations. Extinction, defined as negative population growth rate, occurred after exposure to 0.9 mg/L R-11, 13 mg/L X-77, 25 mg/L Kinetic, 28 mg/L Silwet, 18 mg/L Sylgard, 450 mg/L Bond, 610 mg/L Plyac, and 1,600 mg/L WaterMaxx. Concentrations that caused extinction were substantially below the acute LC50 for R-11, Kinetic, Plyac, X-77, and Bond. The no-observable-effects concentration (NOEC) and lowest-observable-effects concentration (LOEC) for the number of offspring per surviving female after exposure to R-11 were 0.5 and 0.75 mg/L, respectively. The NOEC and LOEC for population size after exposure to R-11 were (1.25 and 0.5 mg/L, respectively. Both of these values were lower than the EEC, indicating that R-11 does have the potential to cause damage to D. pulex populations after application at recommended field rates. The wide range of concentrations causing extinction makes it difficult to generalize about the potential impacts that agricultural adjuvants might have on aquatic ecosystems. Therefore, additional studies that examine effects on other nontarget organisms and determine residues in aquatic ecosystems may be warranted. PMID:14713050

  15. Effects of acute radon progeny exposure on rat alveolar macrophage number and function

    SciTech Connect

    Johnson, N.F.; Newton, G.J.; Guilmette, R.A.

    1992-12-31

    Alveolar macrophages play a key role in removal and translocation of inhaled particles and have been shown to influence proliferation of Alveolar Type II cells and fibroblasts. The effect of radon progeny on alveolar macrophage number and function is not documented. Functional impairment of alveolar macrophages may be an ancillary event in the induction of pulmonary lesions and may also indicate dose to the peripheral lung. In our study, rats were exposed to 1000 working level months (WLM) of radon progeny over a 3- to 5-h period, with a vector aerosol of environmental tobacco smoke. Groups of animals were sacrificed, and the lungs were lavaged immediately after exposure and on days 2, 18, 16, 21 and 29 after exposure. The numbers and viabilities of the lavaged macrophages were determined. Cytological preparations were made to determine the number of binucleated/multinucleated macrophages and macrophages containing micronuclei. The DNA content was measured flow-cytometrically using Hoechst 33342, and phagocytosis was assayed by determining the uptake of fluorescent microspheres. The numbers and viabilities of macrophages recovered from exposed animals were similar to the values measured for control animals. There was no evidence of an inflammatory reaction during any period after radon progeny exposure. Nuclear atypia, evidenced by increases in the number of binucleated cells and cells with micronuclei, occurred in animals 8 days after exposure, and this response peaked at 21 days after exposure. The phagocytic capability of the alveolar macrophages was not significantly affected at any time point after exposure. These results show that there was little functional impairment of alveolar macrophages in rats after acute radon-progeny exposure; however, there was long-standing interference with cell division, resulting in binucleated and micronucleated macrophages.

  16. Body burden profiles of single and mixed solvent exposures

    SciTech Connect

    Brown, W.D.; Setzer, J.V.; Dick, R.B.; Phipps, F.C.; Lowry, L.K.

    1987-11-01

    The dynamics of inhaled solvents have not been studied extensively for exposure conditions involving combinations of chemical agents. An ongoing laboratory study examining psychomotor performance effects on human volunteers exposed to spray paint agents offered an opportunity to gather data on the body burden profiles produced by the inhalation of two solvents alone and in combination. Breath and blood samples were collected from 70 male and female subjects who were randomly assigned to four treatment conditions: chemical placebo, 250 ppm acetone, 200 ppm methyl ethyl ketone, or 125 ppm acetone/100 ppm methyl ethyl ketone. The exposures lasted for four hours. No interaction between the two solvents affecting uptake or elimination was noted. There were no significant differences between the uptake and elimination in males and females. The results are discussed in relation to physiological simulation modeling of the exposure.

  17. Acute but not chronic exposure to abiotic stress results in transient reduction of expression levels of the transgene driven by the 35S promoter.

    PubMed

    Boyko, Alex; Molinier, Jean; Chatter, Waine; Laroche, André; Kovalchuk, Igor

    2010-02-28

    The transgenic plant performance depends on the stable expression of the integrated transgene. In this paper, we have analyzed the stability of the most frequently used constitutive promoter, the cauliflower mosaic virus (CaMV) 35S promoter. We used several independent Nicotiana tabacum lines transgenic for the luciferase (LUC) or green fluorescence protein (GFP) coding genes driven by the same 35S promoter. As an indication of the expression level, we measured the steady state RNA level, protein level and protein activity. Exposure of plants to an acute single dose of UVC, UVB or X-ray radiation resulted in a decrease of the transgene expression level, whereas exposure to high temperature increased it. In most of the cases, the expression changed at one to two hours post exposure and returned to normal at four hours. By contrast, plants germinated and grown in the presence of a low dose of either UVB radiation or CuSO(4) for two weeks did not show any changes in expression level. We conclude that although the expression level of the transgenes driven by the 35S promoter can be transiently altered by the acute exposure, no substantial changes occur upon constant low exposure. PMID:19800040

  18. Acute vertigo in an anesthesia provider during exposure to a 3T MRI scanner

    PubMed Central

    Gorlin, Andrew; Hoxworth, Joseph M; Pavlicek, William; Thunberg, Christopher A; Seamans, David

    2015-01-01

    Vertigo induced by exposure to the magnetic field of a magnetic resonance imaging (MRI) scanner is a well-known phenomenon within the radiology community but is not widely appreciated by other clinical specialists. Here, we describe a case of an anesthetist experiencing acute vertigo while providing sedation to a patient undergoing a 3 Tesla MRI scan. After discussing previous reports, and the evidence surrounding MRI-induced vertigo, we review potential etiologies that include the effects of both static and time-varying magnetic fields on the vestibular apparatus. We conclude our review by discussing the occupational standards that exist for MRI exposure and methods to minimize the risks of MRI-induced vertigo for clinicians working in the MRI environment. PMID:25792858

  19. Acute High-Dose and Chronic Lifetime Exposure to Alcohol Consumption and Differentiated Thyroid Cancer: T-CALOS Korea

    PubMed Central

    Hwang, Yunji; Lee, Kyu Eun; Weiderpass, Elisabete; Park, Young Joo; Chai, Young Jun; Kwon, Hyungju; Park, Do Joon; Cho, BeLong; Choi, Ho-Chun; Kang, Daehee; Park, Sue K.

    2016-01-01

    Background This study evaluated the effects of acute high-dose and chronic lifetime exposure to alcohol and exposure patterns on the development of differentiated thyroid cancer (DTC). Methods The Thyroid Cancer Longitudinal Study (T-CALOS) included 2,258 DTC patients (449 men and 1,809 women) and 22,580 healthy participants (4,490 men and 18,090 women) who were individually matched by age, gender, and enrollment year. In-person interviews were conducted with a structured questionnaire to obtain epidemiologic data. Clinicopathologic features of the patients were obtained by chart reviews. Odds ratios (ORs) and 95% confidence intervals (95%CI) were estimated using conditional regression models. Results While light or moderate drinking behavior was related to a reduced risk of DTC, acute heavy alcohol consumption (151 g or more per event or on a single occasion) was associated with increased risks in men (OR = 2.22, 95%CI = 1.27–3.87) and women (OR = 3.61, 95%CI = 1.52–8.58) compared with never-drinkers. The consumption of alcohol for 31 or more years was a significant risk factor for DTC for both men (31–40 years: OR = 1.58, 95%CI = 1.10–2.28; 41+ years: OR = 3.46, 95%CI = 2.06–5.80) and women (31–40 years: OR = 2.18, 95%CI = 1.62–2.92; 41+ years: OR = 2.71, 95%CI = 1.36–5.05) compared with never-drinkers. The consumption of a large amount of alcohol on a single occasion was also a significant risk factor, even after restricting DTC outcomes to tumor size, lymph node metastasis, extrathyroidal extension and TNM stage. Conclusion The findings of this study suggest that the threshold effects of acute high-dose alcohol consumption and long-term alcohol consumption are linked to an increased risk of DTC. PMID:26985827

  20. Effects of acute ozone exposure on the electrophysiological properties of guinea pig trachea

    SciTech Connect

    Croxton, T.L.; Takahashi, Masahiko; Kokia, Ira

    1994-12-31

    Acute ozone (O{sub 3}) exposures produce an increase in the apparent permeability of the tracheal epithelium, but the mechanism of this response is poorly understood. Comparison of previous studies suggests that qualitative differences may exist between measurements made in vivo or in vitro. To test this possibility we used both in vitro and in vivo electrophysiological techniques to investigate the effects of O{sub 3} exposure on guinea pig tracheal epithelium. Male Hartley guinea pigs were exposed to either 1 or 2 ppm O{sub 3} or to filtered air for 3 h and were studied 0, 6, or 24 h after exposure. Air-exposed animals had in vitro mean tracheal potential (V{sub T}) -32.0 {+-} 1.5 mV, conductance (G{sub T}{sup L}) 2.18 {+-} 0.22 mS/cm, short-circuit current (I{sub SC}{sup L}) 62.6 {+-} 3.7 {mu}A/cm, and diameter (D) 2.44 {+-} 0.10 mm. In vitro properties after 1 ppm O{sub 3} exposure did not differ at any time point from control. Two parts per million O{sub 3} increased I{sub SC}{sup L}, but only at 6 h postexposure. The effect of O{sub 3} on I{sub SC}{sup L} was abolished by amiloride. There were no significant changes in V{sub T}, G{sub T}{sup L}, or D. In vivo tracheal potential under pentobarbital anesthesia was -19.7 {+-} 1.7 mV. At 6 h postexposure to 2 ppm O{sub 3}, but not at 0 or 24 h, in vivo V{sub I} was increased. Thus, acute exposure of guinea pigs to a high concentration of O{sub 3} caused a delayed increase in Na{sup +} absorption by the trachea with no change in conductance. This indicates that paracellular permeability of guinea pig tracheal epithelium was not substantially increased by acute O{sub 3} and suggests that enhanced macromolecular uptake in this species probably occurs transcellularly. 24 refs., 1 fig., 2 tabs.

  1. Acute Inhalation Exposure to Vaporized Methamphetamine Causes Lung Injury in Mice

    PubMed Central

    Wells, Sandra M.; Buford, Mary C.; Braseth, Sarah N.; Hutchison, James D.; Holian, Andrij

    2009-01-01

    Methamphetamine (MA) is currently the most widespread illegally used stimulant in the United States. Use of MA by smoking is the fastest growing mode of administration, which increases concerns about potential pulmonary and other medical complications. A murine exposure system was developed to study the pulmonary affects of inhaled MA. Mice were exposed to 25–100 mg vaporized MA and assessments were made 3 h following initiation of exposure to model acute lung injury. Inhalation of MA vapor resulted in dose-dependent increases in MA plasma levels that were in the range of those experienced by MA users. At the highest MA dose, histological changes were observed in the lung and small but significant increases in lung wet weight to body weight ratios (5.656 ± 0.176 mg/g for the controls vs. 6.706± 0.135 mg/g for the 100 mg MA-exposed mice) were found. In addition, there was 53% increase in total protein in bronchoalveolar lavage (BAL) fluid, greater than 20% increase in albumin levels in the BAL fluid, greater than 2.5-fold increase in lactate dehydrogenase levels in the BAL fluid, and reduced total BAL cell numbers (approximately 77% of controls). Levels of the early response cytokines tumor necrosis factor (TNF)-α and interleukin (IL)-6 were dose-dependently increased in BAL fluid of MA-exposed mice. Exposure to 100 mg MA significantly increased free radical generation in the BAL cells to 107–146% of controls and to approximately 135% of the controls in lung tissue in situ. Together, these data show that acute inhalation exposure to relevant doses of volatilized MA is associated with elevated free radical formation and significant lung injury. PMID:18645723

  2. The desmosomal protein Desmoglein 1 aids recovery of epidermal differentiation after acute ultraviolet light exposure

    PubMed Central

    Johnson, Jodi L.; Koetsier, Jennifer L.; Sirico, Anna; Agidi, Ada T.; Antonini, Dario; Missero, Caterina; Green, Kathleen J.

    2014-01-01

    Epidermal structure is damaged by exposure to ultraviolet (UV) light but the molecular mechanisms governing structural repair are largely unknown. UVB (290-320 nm wavelengths) exposure prior to induction of differentiation reduced expression of differentiation-associated proteins, including Desmoglein 1 (Dsg1), Desmocollin 1 (Dsc1) and Keratins 1 and 10 (K1/K10) in a dose-dependent manner in normal human epidermal keratinocytes (NHEKs). The UVB- induced reduction in both Dsg1 transcript and protein was associated with reduced binding of the p63 transcription factor to previously unreported enhancer regulatory regions of the Dsg1 gene. Since Dsg1 promotes epidermal differentiation in addition to participating in cell-cell adhesion, the role of Dsg1 in aiding differentiation after UVB damage was tested. Compared to controls, depleting Dsg1 via shRNA resulted in further reduction of Dsc1 and K1/K10 expression in monolayer NHEK cultures and in abnormal epidermal architecture in organotypic skin models recovering from UVB exposure. Ectopic expression of Dsg1 in keratinocyte monolayers rescued the UVB-induced differentiation defect. Treatment of UVB-exposed monolayer or organotypic cultures with Trichostatin A, a histone deacetylase inhibitor, partially restored differentiation marker expression, suggesting a potential therapeutic strategy for reversing UV-induced impairment of epidermal differentiation after acute sun exposure. PMID:24594668

  3. Gene expression changes in female zebrafish (Danio rerio) brain in response to acute exposure to methylmercury

    USGS Publications Warehouse

    Richter, Catherine A.; Garcia-Reyero, Natàlia; Martyniuk, Chris; Knoebl, Iris; Pope, Marie; Wright-Osment, Maureen K.; Denslow, Nancy D.; Tillitt, Donald E.

    2011-01-01

    Methylmercury (MeHg) is a potent neurotoxicant and endocrine disruptor that accumulates in aquatic systems. Previous studies have shown suppression of hormone levels in both male and female fish, suggesting effects on gonadotropin regulation in the brain. The gene expression profile in adult female zebrafish whole brain induced by acute (96 h) MeHg exposure was investigated. Fish were exposed by injection to 0 or 0.5(mu or u)g MeHg/g. Gene expression changes in the brain were examined using a 22,000-feature zebrafish microarray. At a significance level of pexposure. Individual genes exhibiting altered expression in response to MeHg exposure implicate effects on glutathione metabolism in the mechanism of MeHg neurotoxicity. Gene ontology (GO) terms significantly enriched among altered genes included protein folding, cell redox homeostasis, and steroid biosynthetic process. The most affected biological functions were related to nervous system development and function, as well as lipid metabolism and molecular transport. These results support the involvement of oxidative stress and effects on protein structure in the mechanism of action of MeHg in the female brain. Future studies will compare the gene expression profile induced in response to MeHg with that induced by other toxicants and will investigate responsive genes as potential biomarkers of MeHg exposure.

  4. Exposure to Discrimination and Heart Rate Variability Reactivity to Acute Stress among Women with Diabetes.

    PubMed

    Wagner, Julie; Lampert, Rachel; Tennen, Howard; Feinn, Richard

    2015-08-01

    Exposure to racial discrimination has been linked to physiological reactivity. This study investigated self-reported exposure to racial discrimination and parasympathetic [high-frequency heart rate variability (HF-HRV)] and sympathetic (norepinephrine and cortisol) activity at baseline and then again after acute laboratory stress. Lifetime exposure to racial discrimination was measured with the Schedule of Racist Events scale. Thirty-two women (16 Black and 16 White) with type 2 diabetes performed a public speaking stressor. Beat-to-beat intervals were recorded on electrocardiograph recorders, and HF-HRV was calculated using spectral analysis and natural log transformed. Norepinephrine and cortisol were measured in blood. Higher discrimination predicted lower stressor HF-HRV, even after controlling for baseline HF-HRV. When race, age, A1c and baseline systolic blood pressure were also controlled, racial discrimination remained a significant independent predictor of stressor HF-HRV. There was no association between lifetime discrimination and sympathetic markers. In conclusion, preliminary data suggest that among women with type 2 diabetes mellitus (T2DM), exposure to racial discrimination is adversely associated with parasympathetic, but not sympathetic, reactivity. PMID:24194397

  5. GENE EXPRESSION CHANGES IN FEMALE ZEBRAFISH (DANIO RERIO) BRAIN IN RESPONSE TO ACUTE EXPOSURE TO METHYLMERCURY

    PubMed Central

    Richter, Catherine A.; Garcia-Reyero, Natàlia; Martyniuk, Chris; Knoebl, Iris; Pope, Marie; Wright-Osment, Maureen K.; Denslow, Nancy D.; Tillitt, Donald E.

    2010-01-01

    Methylmercury (MeHg) is a potent neurotoxicant and endocrine disruptor that accumulates in aquatic systems. Previous studies have shown suppression of hormone levels in both male and female fish, suggesting effects on gonadotropin regulation in the brain. The gene expression profile in adult female zebrafish whole brain induced by acute (96 hr) MeHg exposure was investigated. Fish were exposed by injection to 0 or 0.5 μg MeHg/g. Gene expression changes in the brain were examined using a 22,000 feature zebrafish microarray. At a significance level of p<0.01, 79 genes were up-regulated and 76 genes were down-regulated in response to MeHg exposure. Individual genes exhibiting altered expression in response to MeHg exposure implicate effects on glutathione metabolism in the mechanism of MeHg neurotoxicity. Gene ontology (GO) terms significantly enriched among altered genes included protein folding, cell redox homeostasis, and steroid biosynthetic process. The most affected biological functions were related to the nervous system development and function, as well as lipid metabolism and molecular transport. These results support the involvement of oxidative stress and effects on protein structure in the mechanism of action of MeHg in the female brain. Future studies will compare the gene expression profile induced in response to MeHg with that induced by other toxicants and investigate responsive genes as potential biomarkers of MeHg exposure. PMID:21082716

  6. Acute health effects associated with exposure to volcanic air pollution (vog) from increased activity at Kilauea Volcano in 2008.

    PubMed

    Longo, Bernadette M; Yang, Wei; Green, Joshua B; Crosby, Frederick L; Crosby, Vickie L

    2010-01-01

    In 2008, the Kilauea Volcano on the island of Hawai'i increased eruption activity and emissions of sulfurous volcanic air pollution called vog. The purpose of this study was to promptly assess for a relative increase in cases of medically diagnosed acute illnesses in an exposed Hawaiian community. Using a within-clinic retrospective cohort design, comparisons were made for visits of acute illnesses during the 14 wk prior to the increased volcanic emissions (low exposure) to 14 wk of high vog exposure when ambient sulfur dioxide was threefold higher and averaged 75 parts per billion volume per day. Logistic regression analysis estimated effect measures between the low- and high-exposure cohorts for age, gender, race, and smoking status. There were statistically significant positive associations between high vog exposure and visits for medically diagnosed cough, headache, acute pharyngitis, and acute airway problems. More than a sixfold increase in odds was estimated for visits with acute airway problems, primarily experienced by young Pacific Islanders. These findings suggest that the elevated volcanic emissions in 2008 were associated with increased morbidity of acute illnesses in age and racial subgroups of the general Hawaiian population. Continued investigation is crucial to fully assess the health impact of this natural source of sulfurous air pollution. Culturally appropriate primary- and secondary-level health prevention initiatives are recommended for populations in Hawai'i and volcanically active areas worldwide. PMID:20818536

  7. Acute Air Pollution Exposure and Blood Pressure at Delivery Among Women With and Without Hypertension

    PubMed Central

    Männistö, Tuija; Liu, Danping; Leishear, Kira; Sherman, Seth; Laughon, S. Katherine

    2015-01-01

    BACKGROUND Chronic air pollution exposure increases risk for hypertensive disorders of pregnancy, but the effect of acute air pollution exposure on blood pressure during pregnancy is less well known. METHODS We studied 151,276 singleton term deliveries from the Consortium on Safe Labor (2002–2008) with clinical blood pressure measured at admission to labor/delivery and diagnoses of hypertensive disorders collected from electronic medical records and hospital discharge summaries. Air pollution exposures were estimated for the admission hour and the 4 hours preceding admission using a modified version of the Community Multiscale Air Quality models and observed air monitoring data. Blood pressure was categorized as normal; high normal; and mild, moderate, or severe hypertension based on pregnancy cut points. Adjusted ordinal logistic regression estimated the odds of women having a higher admission blood pressure category as a function of air pollutant, hypertensive disorders, and their interaction effect. RESULTS Odds of high blood pressure at admission to labor/delivery were increased in normotensive women after exposure to nitrogen oxides (by 0.2%/5 units), sulfur dioxide (by 0.3%/1 unit), carbon monoxide and several air toxics (by 3%–4%/high exposure). The effects were often similar or stronger among women with gestational hypertension and preeclampsia. Exposure to particulate matter <10 μm increased odds of high blood pressure in women with preeclampsia by 3%/5 units. CONCLUSIONS Air pollution can influence admission blood pressure in term deliveries and may increase likelihood of preeclampsia screening at delivery admission. PMID:24795401

  8. Acute lipopolysaccharide exposure facilitates epileptiform activity via enhanced excitatory synaptic transmission and neuronal excitability in vitro

    PubMed Central

    Gao, Fei; Liu, Zhiqiang; Ren, Wei; Jiang, Wen

    2014-01-01

    Growing evidence indicates brain inflammation has been involved in the genesis of seizures. However, the direct effect of acute inflammation on neuronal circuits is not well known. Lipopolysaccharide (LPS) has been used extensively to stimulate brain inflammatory responses both in vivo and in vitro. Here, we observed the contribution of inflammation induced by 10 μg/mL LPS to the excitability of neuronal circuits in acute hippocampal slices. When slices were incubated with LPS for 30 minutes, significant increased concentration of tumor necrosis factor α and interleukin 1β were detected by enzyme-linked immunosorbent assay. In electrophysiological recordings, we found that frequency of epileptiform discharges and spikes per burst increased 30 minutes after LPS application. LPS enhanced evoked excitatory postsynaptic currents but did not modify evoked inhibitory postsynaptic currents. In addition, exposure to LPS enhanced the excitability of CA1 pyramidal neurons, as demonstrated by a decrease in rheobase and an increase in action potential frequency elicited by depolarizing current injection. Our observations suggest that acute inflammation induced by LPS facilitates epileptiform activity in vitro and that enhancement of excitatory synaptic transmission and neuronal excitability may contribute to this facilitation. These results may provide new clues for treating seizures associated with brain inflammatory disease. PMID:25170268

  9. Evidence Report: Risk of Acute and Late Central Nervous System Effects from Radiation Exposure

    NASA Technical Reports Server (NTRS)

    Nelson, Gregory A.; Simonsen, Lisa; Huff, Janice L.

    2016-01-01

    Possible acute and late risks to the central nervous system (CNS) from galactic cosmic rays (GCR) and solar particle events (SPE) are concerns for human exploration of space. Acute CNS risks may include: altered cognitive function, reduced motor function, and behavioral changes, all of which may affect performance and human health. Late CNS risks may include neurological disorders such as Alzheimer's disease (AD), dementia and premature aging. Although detrimental CNS changes are observed in humans treated with high-dose radiation (e.g., gamma rays and 9 protons) for cancer and are supported by experimental evidence showing neurocognitive and behavioral effects in animal models, the significance of these results on the morbidity to astronauts has not been elucidated. There is a lack of human epidemiology data on which to base CNS risk estimates; therefore, risk projection based on scaling to human data, as done for cancer risk, is not possible for CNS risks. Research specific to the spaceflight environment using animal and cell models must be compiled to quantify the magnitude of CNS changes in order to estimate this risk and to establish validity of the current permissible exposure limits (PELs). In addition, the impact of radiation exposure in combination with individual sensitivity or other space flight factors, as well as assessment of the need for biological/pharmaceutical countermeasures, will be considered after further definition of CNS risk occurs.

  10. Diphenyl diselenide protects against metabolic disorders induced by acephate acute exposure in rats.

    PubMed

    Acker, Carmine Inês; Nogueira, Cristina Wayne

    2014-06-01

    The present study investigated the effect of diphenyl diselenide [(PhSe)2 ] on metabolic disorders induced by acephate acute exposure in rats. We also investigated a possible mechanism of action of (PhSe)2 against hyperglycemia induced by acephate. (PhSe)2 was administered to rats at a dose of 10 or 30 mg/kg by oral gavage (p.o.) 1 hour prior to acephate administration (140 mg/kg; p.o.). Glucose and corticosterone levels as well as the lipid status were determined in plasma of rats. Cardiovascular risk factors and the atherogenic index were calculated. Glycogen levels as well as tyrosine aminotransferase (TAT) and glucose-6-phosphatase (G6Pase) activities were determined in livers of rats. Cerebral acetylcholinesterase (AChE) activity was assayed. Acephate induced an increase in glucose and corticosterone levels as well as in TAT and G6Pase activities. AChE activity was inhibited by acephate. Triglyceride (TG) levels and the cardiovascular risk factor TG/high-density lipoprotein-cholesterol (HDL) were increased by acephate. (PhSe)2 was effective against the metabolic disorders induced by acephate acute exposure in rats. PMID:22778074

  11. Transcriptional Response to Acute Thermal Exposure in Juvenile Chinook Salmon Determined by RNAseq

    PubMed Central

    Tomalty, Katharine M. H.; Meek, Mariah H.; Stephens, Molly R.; Rincón, Gonzalo; Fangue, Nann A.; May, Bernie P.; Baerwald, Melinda R.

    2015-01-01

    Thermal exposure is a serious and growing challenge facing fish species worldwide. Chinook salmon (Oncorhynchus tshawytscha) living in the southern portion of their native range are particularly likely to encounter warmer water due to a confluence of factors. River alterations have increased the likelihood that juveniles will be exposed to warm water temperatures during their freshwater life stage, which can negatively impact survival, growth, and development and pose a threat to dwindling salmon populations. To better understand how acute thermal exposure affects the biology of salmon, we performed a transcriptional analysis of gill tissue from Chinook salmon juveniles reared at 12° and exposed acutely to water temperatures ranging from ideal to potentially lethal (12° to 25°). Reverse-transcribed RNA libraries were sequenced on the Illumina HiSeq2000 platform and a de novo reference transcriptome was created. Differentially expressed transcripts were annotated using Blast2GO and relevant gene clusters were identified. In addition to a high degree of downregulation of a wide range of genes, we found upregulation of genes involved in protein folding/rescue, protein degradation, cell death, oxidative stress, metabolism, inflammation/immunity, transcription/translation, ion transport, cell cycle/growth, cell signaling, cellular trafficking, and structure/cytoskeleton. These results demonstrate the complex multi-modal cellular response to thermal stress in juvenile salmon. PMID:25911227

  12. Acute nonlymphocytic leukemia and residential exposure to power frequency magnetic fields

    SciTech Connect

    Severson, R.K.

    1986-01-01

    A population-based case-control study of adult acute nonlymphocytic leukemia (ANLL) and residential exposure to power frequency magnetic fields was conducted in King, Pierce and Snohomish Counties in Washington state. Of 164 cases who were diagnosed from January 1, 1981 through December 31, 1984, 114 were interviewed. Controls were selected from the study area on the basis of random digit dialing and frequency matched to the cases by age and sex. Analyses were undertaken to evaluate whether exposure to high levels of power frequency magnetic fields in the residence were associated with an increased risk of ANLL. Neither the directly measured magnetic fields nor the surrogate values based on the wiring configurations were associated with ANLL. Additional analyses suggested that persons with prior allergies were at decreased risk of acute myelocytic leukemia (AML). Also, persons with prior autoimmune diseases were at increased risk of AML. The increase in AML risk in rheumatoid arthritics was of borderline statistical significance. Finally, cigarette smoking was associated with an increased risk of AML. The risk of AML increased significantly with the number of years of cigarette smoking.

  13. Cardiovascular and cerebrovascular responses to acute hypoxia following exposure to intermittent hypoxia in healthy humans

    PubMed Central

    Foster, Glen E; Brugniaux, Julien V; Pialoux, Vincent; Duggan, Cailean T C; Hanly, Patrick J; Ahmed, Sofia B; Poulin, Marc J

    2009-01-01

    Intermittent hypoxia (IH) is thought to be responsible for many of the long-term cardiovascular consequences associated with obstructive sleep apnoea (OSA). Experimental human models of IH can aid in investigating the pathophysiology of these cardiovascular complications. The purpose of this study was to determine the effects of IH on the cardiovascular and cerebrovascular response to acute hypoxia and hypercapnia in an experimental human model that simulates the hypoxaemia experienced by OSA patients. We exposed 10 healthy, male subjects to IH for 4 consecutive days. The IH profile involved 2 min of hypoxia (nadir = 45.0 mmHg) alternating with 2 min of normoxia (peak = 88.0 mmHg) for 6 h. The cerebral blood flow response and the pressor responses to hypoxia and hypercapnia were assessed after 2 days of sham exposure, after each day of IH, and 4 days following the discontinuation of IH. Nitric oxide derivatives were measured at baseline and following the last exposure to IH. After 4 days of IH, mean arterial pressure increased by 4 mmHg (P < 0.01), nitric oxide derivatives were reduced by 55% (P < 0.05), the pressor response to acute hypoxia increased (P < 0.01), and the cerebral vascular resistance response to hypoxia increased (P < 0.01). IH alters blood pressure and cerebrovascular regulation, which is likely to contribute to the pathogenesis of cardiovascular and cerebrovascular disease in patients with OSA. PMID:19417094

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

    PubMed

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

    2011-03-01

    The aim of this study was to fine-tune previous acute cold exposure treatments of broiler embryos during late embryogenesis to improve lifelong cold resistance and performance. Six hundred Cobb hatching eggs were incubated under standard conditions and then exposed to 3 treatments: control; cold treatment in which embryos were exposed to 15°C for 30 min on d 18 and 19 of incubation (30 × 2); and cold treatment similar to 30 × 2 but with 60-min exposures (60 × 2). Egg shell temperature (T(egg)) and heart rate (HR) were monitored pre- and posttreatment. Upon hatching, hatchability, body weight, and body temperature were recorded. From 14 to 35 d of age, three quarters of the chickens in each treatment were raised under ascites-inducing conditions (AIC) and the remaining birds were raised under standard brooding conditions (SBC). The T(egg) and HR decreased significantly in response to increased exposure time on d 18 of incubation. On d 19 of incubation, before the second cold exposure, the 30 × 2 group showed greater T(egg) and HR than the controls, and during the second exposure they maintained these parameters better than the 60 × 2 embryos. No treatment effect on hatchability was observed. At 35 d of age ascites incidence among 30 × 2 chickens under AIC was significantly less than that among the controls (P < 0.01), and body weight of these chickens under either SBC or AIC was significantly higher than that of the controls. Under SBC relative breast muscle weight was significantly higher in 60 × 2 chickens, whereas the relative heart weight was higher in both cold-treated groups than in the controls. It can be concluded that repeated short acute cold exposures during late embryogenesis significantly reduced ascites incidence and improved growth rate under either SBC or AIC. These results may be related to a prenatal epigenetic adaptation of the thermoregulatory and cardiovascular systems to low ambient temperature. PMID:21325235

  15. Work-Time Exposure and Acute Injuries in Inshore Lobstermen of the Northeast United States.

    PubMed

    Fulmer, Scott; Buchholz, Bryan; Jenkins, Paul; Scribani, Melissa

    2016-01-01

    The objective of this study was to inform efforts to reduce risk for musculoskeletal disorders among commercial lobstermen by characterizing and quantifying injuries that occur to people while harvesting lobsters commercially in the Northeast United States. This study aimed to estimate a denominator of exposure to lobstering in full-time equivalents (FTE), to estimate a fatality rate, and to calculate incidence rates for acute injuries within the sample population. Captains were randomly selected from those licensed to fish in Maine and Massachusetts. Data on work exposure and injuries with rapid onset that occurred on the boat ("acute injuries") were collected using a survey, which was administered quarterly via phone or face-to-face interview with the captain. The quarterly survey assessed the number of weeks worked during the quarter, average crew size, number of trips per week, and average trip length in hours. In addition, this survey captured relevant information (body segment affected, type of injury, and whether treatment was received) on all acute injuries occurring during the quarter. FTE were estimated using fishermen days and fishermen hours. The annual FTE estimated using days was 2,557 and using hours was 2,855. As expected, the summer months (3rd quarter) had the highest FTE and the winter (1st quarter) the lowest FTE. Fall (4th quarter) and spring (2nd quarter) ranked second and third, respectively. The incidence rates for all injuries (49.7/100 FTE) and injuries requiring treatment (15.0/100 FTE) were much higher than those reported in other studies of fishing that used Coast Guard data. PMID:26788780

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

    PubMed

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

    2006-05-01

    Short-term (<48 h) and long-term (21 d) effects of dimethoate and pirimicarb were studied in 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

  17. Single dose oral piroxicam for acute postoperative pain

    PubMed Central

    Moore, R Andrew; Edwards, Jayne; Loke, Yoon; Derry, Sheena; McQuay, Henry J

    2014-01-01

    Background This is an updated version of the original Cochrane review published in Issue 2, 2000. Piroxicam is a non-steroidal anti-inflammatory drug (NSAID) with analgesic properties, and is used mainly for treating rheumatic disorders. Some drugs have been directly compared against each other within a trial setting to determine their relative efficacies, whereas other have not. It is possible, however, to compare analgesics indirectly by examining the effectiveness of each drug against placebo when used in similar clinical situations. Objectives To determine the analgesic efficacy and adverse effects of single-dose piroxicam compared with placebo in moderate to severe postoperative pain. To compare the effects of piroxicam with other analgesics. Search methods Published studies were identified from systematic searching of MEDLINE, Biological Abstracts, EMBASE, CENTRAL and the Oxford Pain Relief Database in December 2007. Additional studies were identified from the reference lists of retrieved reports. Selection criteria The following inclusion criteria were used: full journal publication, randomised placebo controlled trial, double-blind design, adult participants, postoperative pain of moderate to severe intensity at the baseline assessment, postoperative administration of oral or intramuscular piroxicam. Data collection and analysis Summed pain intensity and pain relief data were extracted and converted into dichotomous information to yield the number of participants obtaining at least 50% pain relief. This was used to calculate estimates of relative benefit and number-needed-to-treat-to-benefit (NNT) for one participant to obtain at least 50% pain relief. Information was collected on adverse effects and estimates of relative risk and number-needed-to-treat-to-harm (NNH) were calculated. Main results In this update no further studies were found. The original search identified three studies (141 participants) which compared oral piroxicam 20 mg with placebo and

  18. Flaxseed Mitigates Acute Oxidative Lung Damage in a Mouse Model of Repeated Radiation and Hyperoxia Exposure Associated with Space Exploration

    PubMed Central

    Pietrofesa, Ralph A.; Solomides, Charalambos C.; Christofidou-Solomidou, Melpo

    2015-01-01

    Background Spaceflight missions may require crewmembers to conduct extravehicular activities (EVA). Pre-breathe protocols in preparation for an EVA entail 100% hyperoxia exposure that may last for a few hours and be repeated 2-3 times weekly. Each EVA is associated with additional challenges such as low levels of total body cosmic/galactic radiation exposure that may present a threat to crewmember health. We have developed a mouse model of total body radiation and hyperoxia exposure and identified acute damage of lung tissues. In the current study we evaluated the usefulness of dietary flaxseed (FS) as a countermeasure agent for such double-hit exposures. Methods We evaluated lung tissue changes 2 weeks post-initiation of exposure challenges. Mouse cohorts (n=5/group) were pre-fed diets containing either 0% FS or 10% FS for 3 weeks and exposed to: a) normoxia (Untreated); b) >95% O2 (O2); c) 0.25Gy single fraction gamma radiation (IR); or d) a combination of O2 and IR (O2+IR) 3 times per week for 2 consecutive weeks, where 8-hour hyperoxia treatments were spanned by normoxic intervals. Results At 2 weeks post challenge, while control-diet fed mice developed significant lung injury and inflammation across all challenges, FS protected lung tissues by decreasing bronchoalveolar lavage fluid (BALF) neutrophils (p<0.003) and protein levels, oxidative tissue damage, as determined by levels of malondialdehyde (MDA) (p<0.008) and nitrosative stress as determined by nitrite levels. Lung hydroxyproline levels, a measure of lung fibrosis, were significantly elevated in mice fed 0% FS (p<0.01) and exposed to hyperoxia/radiation or the combination treatment, but not in FS-fed mice. FS also decreased levels of a pro-inflammatory, pro-fibrogenic cytokine (TGF-β1) gene expression levels in lung. Conclusion Flaxseed mitigated adverse effects in lung of repeat exposures to radiation/hyperoxia. This data will provide useful information in the design of countermeasures to early

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

    PubMed

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

    2015-01-01

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

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

    PubMed Central

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

    2015-01-01

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

  1. Combined Exposure to Simulated Microgravity and Acute or Chronic Radiation Reduces Neuronal Network Integrity and Survival

    PubMed Central

    Quintens, Roel; Samari, Nada; de Saint-Georges, Louis; van Oostveldt, Patrick; Baatout, Sarah; Benotmane, Mohammed Abderrafi

    2016-01-01

    During orbital or interplanetary space flights, astronauts are exposed to cosmic radiations and microgravity. However, most earth-based studies on the potential health risks of space conditions have investigated the effects of these two conditions separately. This study aimed at assessing the combined effect of radiation exposure and microgravity on neuronal morphology and survival in vitro. In particular, we investigated the effects of simulated microgravity after acute (X-rays) or during chronic (Californium-252) exposure to ionizing radiation using mouse mature neuron cultures. Acute exposure to low (0.1 Gy) doses of X-rays caused a delay in neurite outgrowth and a reduction in soma size, while only the high dose impaired neuronal survival. Of interest, the strongest effect on neuronal morphology and survival was evident in cells exposed to microgravity and in particular in cells exposed to both microgravity and radiation. Removal of neurons from simulated microgravity for a period of 24 h was not sufficient to recover neurite length, whereas the soma size showed a clear re-adaptation to normal ground conditions. Genome-wide gene expression analysis confirmed a modulation of genes involved in neurite extension, cell survival and synaptic communication, suggesting that these changes might be responsible for the observed morphological effects. In general, the observed synergistic changes in neuronal network integrity and cell survival induced by simulated space conditions might help to better evaluate the astronaut's health risks and underline the importance of investigating the central nervous system and long-term cognition during and after a space flight. PMID:27203085

  2. Combined Exposure to Simulated Microgravity and Acute or Chronic Radiation Reduces Neuronal Network Integrity and Survival.

    PubMed

    Pani, Giuseppe; Verslegers, Mieke; Quintens, Roel; Samari, Nada; de Saint-Georges, Louis; van Oostveldt, Patrick; Baatout, Sarah; Benotmane, Mohammed Abderrafi

    2016-01-01

    During orbital or interplanetary space flights, astronauts are exposed to cosmic radiations and microgravity. However, most earth-based studies on the potential health risks of space conditions have investigated the effects of these two conditions separately. This study aimed at assessing the combined effect of radiation exposure and microgravity on neuronal morphology and survival in vitro. In particular, we investigated the effects of simulated microgravity after acute (X-rays) or during chronic (Californium-252) exposure to ionizing radiation using mouse mature neuron cultures. Acute exposure to low (0.1 Gy) doses of X-rays caused a delay in neurite outgrowth and a reduction in soma size, while only the high dose impaired neuronal survival. Of interest, the strongest effect on neuronal morphology and survival was evident in cells exposed to microgravity and in particular in cells exposed to both microgravity and radiation. Removal of neurons from simulated microgravity for a period of 24 h was not sufficient to recover neurite length, whereas the soma size showed a clear re-adaptation to normal ground conditions. Genome-wide gene expression analysis confirmed a modulation of genes involved in neurite extension, cell survival and synaptic communication, suggesting that these changes might be responsible for the observed morphological effects. In general, the observed synergistic changes in neuronal network integrity and cell survival induced by simulated space conditions might help to better evaluate the astronaut's health risks and underline the importance of investigating the central nervous system and long-term cognition during and after a space flight. PMID:27203085

  3. Acute 7,12-dimethylbenz[a]anthracene exposure causes differential concentration-dependent follicle depletion and gene expression in neonatal rat ovaries

    SciTech Connect

    Madden, Jill A.; Hoyer, Patricia B.; Devine, Patrick J.; Keating, Aileen F.

    2014-05-01

    Chronic exposure to the polycyclic aromatic hydrocarbon 7,12-dimethylbenz[a]anthracene (DMBA), generated during combustion of organic matter including cigarette smoke, depletes all ovarian follicle types in the mouse and rat, and in vitro models mimic this effect. To investigate the mechanisms involved in follicular depletion during acute DMBA exposure, two concentrations of DMBA at which follicle depletion has (75 nM) and has not (12.5 nM) been observed were investigated. Postnatal day four F344 rat ovaries were maintained in culture for four days before a single exposure to vehicle control (1% DMSO; CT) or DMBA (12 nM; low-concentration or 75 nM; high-concentration). After four or eight additional days of culture, DMBA-induced follicle depletion was evaluated via follicle enumeration. Relative to control, DMBA did not affect follicle numbers after 4 days of exposure, but induced large primary follicle loss at both concentrations after 8 days; while, the low-concentration DMBA also caused secondary follicle depletion. Neither concentration affected primordial or small primary follicle number. RNA was isolated and quantitative RT-PCR performed prior to follicle loss to measure mRNA levels of genes involved in xenobiotic metabolism (Cyp2e1, Gstmu, Gstpi, Ephx1), autophagy (Atg7, Becn1), oxidative stress response (Sod1, Sod2) and the phosphatidylinositol 3-kinase (PI3K) pathway (Kitlg, cKit, Akt1) 1, 2 and 4 days after exposure. With the exception of Atg7 and cKit, DMBA increased (P < 0.05) expression of all genes investigated. Also, BECN1 and pAKT{sup Thr308} protein levels were increased while cKIT was decreased by DMBA exposure. Taken together, these results suggest an increase in DMBA bioactivation, add to the mechanistic understanding of DMBA-induced ovotoxicity and raise concern regarding female low concentration DMBA exposures. - Highlights: • Acute DMBA exposures induce large primary and/or secondary follicle loss. • Acute DMBA exposure did not impact

  4. The Effect of Exposure Duration on Visual Character Identification in Single, Whole, and Partial Report

    ERIC Educational Resources Information Center

    Petersen, Anders; Andersen, Tobias S.

    2012-01-01

    The psychometric function of single-letter identification is typically described as a function of stimulus intensity. However, the effect of stimulus exposure duration on letter identification remains poorly described. This is surprising because the effect of exposure duration has played a central role in modeling performance in whole and partial…

  5. Neurotoxicity following acute inhalation exposure to the oil dispersant COREXIT EC9500A.

    PubMed

    Sriram, Krishnan; Lin, Gary X; Jefferson, Amy M; Goldsmith, William T; Jackson, Mark; McKinney, Walter; Frazer, David G; Robinson, Victor A; Castranova, Vincent

    2011-01-01

    Consequent to the 2010 Deepwater Horizon oil spill in the Gulf of Mexico, there is an emergent concern about the short- and long-term adverse health effects of exposure to crude oil, weathered-oil products, and oil dispersants among the workforce employed to contain and clean up the spill. Oil dispersants typically comprise of a mixture of solvents and surfactants that break down floating oil to micrometer-sized droplets within the water column, thus preventing it from reaching the shorelines. As dispersants are generally sprayed from the air, workers are at risk for exposure primarily via inhalation. Such inhaled fractions might potentially permeate or translocate to the brain via olfactory or systemic circulation, producing central nervous system (CNS) abnormalities. To determine whether oil dispersants pose a neurological risk, male Sprague-Dawley rats were exposed by whole-body inhalation exposure to a model oil dispersant, COREXIT EC9500A (CE; approximately 27 mg/m(3) × 5 h/d × 1 d), and various molecular indices of neural dysfunction were evaluated in discrete brain areas, at 1 or 7 d postexposure. Exposure to CE produced partial loss of olfactory marker protein in the olfactory bulb. CE also reduced tyrosine hydroxylase protein content in the striatum. Further, CE altered the levels of various synaptic and neuronal intermediate filament proteins in specific brain areas. Reactive astrogliosis, as evidenced by increased expression of glial fibrillary acidic protein, was observed in the hippocampus and frontal cortex following exposure to CE. Collectively, these findings are suggestive of disruptions in olfactory signal transduction, axonal function, and synaptic vesicle fusion, events that potentially result in an imbalance in neurotransmitter signaling. Whether such acute molecular aberrations might persist and produce chronic neurological deficits remains to be ascertained. PMID:21916746

  6. NEUROTOXICITY FOLLOWING ACUTE INHALATION EXPOSURE TO THE OIL DISPERSANT COREXIT EC9500A

    PubMed Central

    Sriram, Krishnan; Lin, Gary X.; Jefferson, Amy M.; Goldsmith, William T.; Jackson, Mark; McKinney, Walter; Frazer, David G.; Robinson, Victor A.; Castranova, Vincent

    2015-01-01

    Consequent to the 2010 Deepwater Horizon oil spill in the Gulf of Mexico, there is an emergent concern about the short- and long-term adverse health effects of exposure to crude oil, weathered-oil products, and oil dispersants among the workforce employed to contain and clean up the spill. Oil dispersants typically comprise of a mixture of solvents and surfactants that break down floating oil to micrometer-sized droplets within the water column, thus preventing it from reaching the shorelines. As dispersants are generally sprayed from the air, workers are at risk for exposure primarily via inhalation. Such inhaled fractions might potentially permeate or translocate to the brain via olfactory or systemic circulation, producing central nervous system (CNS) abnormalities. To determine whether oil dispersants pose a neurological risk, male Sprague-Dawley rats were exposed by whole-body inhalation exposure to a model oil dispersant, COREXIT EC9500A (CE; approximately 27 mg/m3 × 5 h/d × 1 d), and various molecular indices of neural dysfunction were evaluated in discrete brain areas, at 1 or 7 d postexposure. Exposure to CE produced partial loss of olfactory marker protein in the olfactory bulb. CE also reduced tyrosine hydroxylase protein content in the striatum. Further, CE altered the levels of various synaptic and neuronal intermediate filament proteins in specific brain areas. Reactive astrogliosis, as evidenced by increased expression of glial fibrillary acidic protein, was observed in the hippocampus and frontal cortex following exposure to CE. Collectively, these findings are suggestive of disruptions in olfactory signal transduction, axonal function, and synaptic vesicle fusion, events that potentially result in an imbalance in neurotransmitter signaling. Whether such acute molecular aberrations might persist and produce chronic neurological deficits remains to be ascertained. PMID:21916746

  7. Immune status influences fear and anxiety responses in mice after acute stress exposure.

    PubMed

    Clark, Sarah M; Sand, Joseph; Francis, T Chase; Nagaraju, Anitha; Michael, Kerry C; Keegan, Achsah D; Kusnecov, Alexander; Gould, Todd D; Tonelli, Leonardo H

    2014-05-01

    Significant evidence suggests that exposure to traumatic and/or acute stress in both mice and humans results in compromised immune function that in turn may affect associated brain processes. Additionally, recent studies in mouse models of immune deficiency have suggested that adaptive immunity may play a role during traumatic stress exposure and that impairments in lymphocyte function may contribute to increased susceptibility to various psychogenic stressors. However, rodent studies on the relationship between maladaptive stress responses and lymphocyte deficiency have been complicated by the fact that genetic manipulations in these models may also result in changes in CNS function due to the expression of targeted genes in tissues other than lymphocytes, including the brain. To address these issues we utilized mice with a deletion of recombination-activating gene 2 (Rag2), which has no confirmed expression in the CNS; thus, its loss should result in the absence of mature lymphocytes without altering CNS function directly. Stress responsiveness of immune deficient Rag2(-/-) mice on a BALB/c background was evaluated in three different paradigms: predator odor exposure (POE), fear conditioning (FC) and learned helplessness (LH). These models are often used to study different aspects of stress responsiveness after the exposure to an acute stressor. In addition, immunoblot analysis was used to assess hippocampal BDNF expression under both stressed and non-stressed conditions. Subsequent to POE, Rag2(-/-) mice exhibited a reduced acoustic startle response compared to BALB/c mice; no significant differences in behavior were observed in either FC or LH. Furthermore, analysis of hippocampal BDNF indicated that Rag2(-/-) mice have elevated levels of the mature form of BDNF compared to BALB/c mice. Results from our studies suggest that the absence of mature lymphocytes is associated with increased resilience to stress exposure in the POE and does not affect behavioral

  8. Acute pergolide exposure stiffens engineered valve interstitial cell tissues and reduces contractility in vitro.

    PubMed

    Capulli, Andrew K; MacQueen, Luke A; O'Connor, Blakely B; Dauth, Stephanie; Parker, Kevin Kit

    2016-01-01

    Medications based on ergoline-derived dopamine and serotonin agonists are associated with off-target toxicities that include valvular heart disease (VHD). Reports of drug-induced VHD resulted in the withdrawal of appetite suppressants containing fenfluramine and phentermine from the US market in 1997 and pergolide, a Parkinson's disease medication, in 2007. Recent evidence suggests that serotonin receptor activity affected by these medications modulates cardiac valve interstitial cell activation and subsequent valvular remodeling, which can lead to cardiac valve fibrosis and dysfunction similar to that seen in carcinoid heart disease. Failure to identify these risks prior to market and continued use of similar drugs reaffirm the need to improve preclinical evaluation of drug-induced VHD. Here, we present two complimentary assays to measure stiffness and contractile stresses generated by engineered valvular tissues in vitro. As a case study, we measured the effects of acute (24 h) pergolide exposure to engineered porcine aortic valve interstitial cell (AVIC) tissues. Pergolide exposure led to increased tissue stiffness, but it decreased both basal and active contractile tone stresses generated by AVIC tissues. Pergolide exposure also disrupted AVIC tissue organization (i.e., tissue anisotropy), suggesting that the mechanical properties and contractile functionality of these tissues are governed by their ability to maintain their structure. We expect further use of these assays to identify off-target drug effects that alter the phenotypic balance of AVICs, disrupt their ability to maintain mechanical homeostasis, and lead to VHD. PMID:27174867

  9. Effects of acute ethanol exposure on cytokine production by primary airway smooth muscle cells.

    PubMed

    Kaphalia, Lata; Kalita, Mridul; Kaphalia, Bhupendra S; Calhoun, William J

    2016-02-01

    Both chronic and binge alcohol abuse can be significant risk factors for inflammatory lung diseases such as acute respiratory distress syndrome and chronic obstructive pulmonary disease. However, metabolic basis of alcohol-related lung disease is not well defined, and may include key metabolites of ethanol [EtOH] in addition to EtOH itself. Therefore, we investigated the effects of EtOH, acetaldehyde [ACE], and fatty acid ethyl esters [FAEEs] on oxidative stress, endoplasmic reticulum (ER) stress, AMP-activated protein kinase (AMPK) signaling and nuclear translocation of phosphorylated (p)-NF-κB p65 in primary human airway smooth muscle (HASM) cells stimulated to produce cytokines using LPS exposure. Both FAEEs and ACE induced evidence of cellular oxidative stress and ER stress, and increased p-NF-κB in nuclear extracts. EtOH and its metabolites decreased p-AMPKα activation, and induced expression of fatty acid synthase, and decreased expression of sirtuin 1. In general, EtOH decreased secretion of IP-10, IL-6, eotaxin, GCSF, and MCP-1. However, FAEEs and ACE increased these cytokines, suggesting that both FAEEs and ACE as compared to EtOH itself are proinflammatory. A direct effect of EtOH could be consistent with blunted immune response. Collectively, these two features of EtOH exposure, coupled with the known inhibition of innate immune response in our model might explain some clinical manifestations of EtOH exposure in the lung. PMID:26721307

  10. Comparison of the responses of children and adults to acute ozone exposure

    SciTech Connect

    McDonnell, W.F.; Chapman, R.S.; Horstman, D.H.; Leigh, M.W.; Salaam, S.A.

    1986-07-01

    The purpose of the paper is to compare the results of two studies in which the respiratory responses of children and adults to acute ozone (O/sub 3/) exposure were measured. Forty-two 18-30 year old males were exposed for 2.5 hours in a controlled environmental chamber to either 0.0 or 0.12 ppm O3 while performing intermittent heavy exercise. Twenty-two 8-11 year old males were exposed in a similar manner to both air and 0.12 ppm O3. Measures of respiratory symptoms and function were made before and after exposure. Adults experienced an increase in the symptom cough and decrements in forced vital capacity and some measures of forced expiratory flow. Children experienced similar decrements in pulmonary function, but had no increase in symptoms. The authors concluded that as measured by pulmonary function children appear to be no more responsive to O3 exposure than are adults and may experience fewer symptoms.

  11. Acute effects of chlorinated resin acid exposure on juvenile rainbow trout, Oncorhynchus mykiss

    SciTech Connect

    Kennedy, C.J.; Sweeting, R.M.; Farrell, A.P.; McKeown, B.A.; Johansen, J.A.

    1995-06-01

    The effects of an acute exposure to either 14-monochlorodehydroabietic acid (MCDHAA) or 12,14-dichlorodehydroabietic acid (DCDHAA) were examined in juvenile rainbow trout, Oncorhynchus mykiss. The experimentally determined 96-h LC50 values (and their 95% confidence limits) were 1.03 (0.72, 1.48) and 0.91 (0.70, 1.21) mg/L, for MCDHAA and DCDHAA, respectively. To measure effects on several biochemical parameters, swimming performance, and disease resistance, juvenile trout were exposed for 24 h to sublethal concentrations of one or the other resin acid in an intermittent-flow respirometer. Hematocrit, plasma lactate, and liver protein were significantly affected by exposure to the highest dose (80% of the 96-h LC50 value) of either of the resin acids. Plasma cortisol levels were 14- and 3-fold higher than were controls. Resistance to infection by Aeromonas salmonicida was significantly reduced; the cumulative percent mortalities due to furunculosis in fish exposed to MCDHAA or DCDHAA reached 20 and 26%, respectively. Swimming performance, measured as critical swimming speed (mean values 6.32 {+-} 0.20 and 5.93 {+-} 0.15 body lengths per second for MCDHAA and DCDHAA, respectively), was not significantly affected by resin acid exposure.

  12. ACUTE CHANGES IN PASSIVE GLENOHUMERAL ROTATION FOLLOWING TENNIS PLAY EXPOSURE IN ELITE FEMALE PLAYERS

    PubMed Central

    Kibler, W. Ben; Myers, Natalie L.; Smith, Belinda J.

    2016-01-01

    Background Alterations in glenohumeral (GH) rotation especially internal rotation and total range of motion have been associated with altered GH kinematics and susceptibility to injury. Researchers have evaluated long-term change in baseball and tennis players, and short-term changes in baseball players. However, acute (short-term) changes in GH rotation have not been evaluated in tennis players. Hypotheses/Purpose The purpose of this study was to quantify short-term glenohumeral rotational changes within a group of professional women's tennis players following competitive play. It was hypothesized that there would be acute alterations in passive glenohumeral internal rotation and total range of motion following episodes of tennis play. Study Design Cohort Study Methods Passive glenohumeral external rotation (GER), glenohumeral internal rotation (GIR), and total range of motion (TROM) were evaluated in a cohort of 79 professional adult female tennis players. Measurements were taken at three different time points (TP): baseline before match play (TP1), immediately after match play (TP2), and 24-hours after baseline (TP3). Results There was a statistically significant decrease in the mean GIR from TP1 (43 ± 11 °) to TP2 (39 ± 9 °) (p=0.002) and from TP1 to TP3 (38 ± 10 °) (p=0.001). All measures were at the level of minimal detectable change (MDC) (4 °) indicating clinical significance. There was a decrease in mean TROM from TP1 (146 ± 11 °) to TP2 (142 ± 12 °) (p=0.04), which was not above MDC (7 °). Subgroup analysis showed that 47% of the players demonstrated a decrease in GIR beyond MDC, and 37% demonstrated a decrease in TROM beyond MDC. GER remained unchanged across all time points (p>0.05). Conclusion Both GIR and TROM were reduced after acute exposure to tennis play. In a large subgroup of the cohort, the changes were clinically significant and approached values previously demonstrated to be associated with

  13. ACUTE NEUROTOXIC EFFECTS OF INHALED PERCHLOROETHYLENE ON PATTERN VISUAL EVOKED POTENTIALS AS A FUNCTION OF EXPOSURE AND ESTIMATED BLOOD AND BRAIN CONCENTRATION.

    EPA Science Inventory

    Previous experiments have shown the effects of acute inhalation exposure to trichloroethylene (TCE) and toluene are related to the target tissue concentration at the time of testing. The current studies examined exposure to another volatile organic compound, perchloroethylene (P...

  14. Response of single cell with acute angle exposed to an external electric field.

    PubMed

    Sarbazvatan, Saber; Sardari, Dariush; Taheri, Nahid; Sepanloo, Kamran

    2015-10-01

    It is known that the electric field incurs effects on the living cells. Predicting the response of single cell or multilayer cells to induced alternative or static eclectic field has permanently been a challenge. In the present study a first order single cell with acute angle under the influence of external electric field is considered. The cell division stage or the special condition of reshaping is modelled with a cone being connected. In the case of cell divisions, anaphase, it can be considered with two cones that connected nose-to-nose. Each cone consists of two regions. The first is the membrane modelled with a superficial layer, and the second is cytoplasm at the core. A Laplace equation is written for this model and the distribution of its electric field is a sharp point in the single cell for which an acute angle model is calculated. PMID:26307458

  15. The effects of acute cold exposure on morphology and gene expression in the heart of neonatal chicks.

    PubMed

    Matsubara, Tomoko; Shimamoto, Saki; Ijiri, Daichi; Ohtsuka, Akira; Kanai, Yukio; Hirabayashi, Miho

    2016-04-01

    Cold exposure induces an increase in blood flow and blood pressure, and long-term exposure to cold causes cardiac hypertrophy. Neonatal chicks (Gallus gallus domesticus) are highly sensitive to cold exposure, because their capacity for thermogenesis is immature until 1 week after hatching. Hence, we hypothesized that the heart of chicks at around 1 week of age acutely responds to cold environment. To investigate the effect of acute (24 h) and long-term (2 weeks) cold on the heart of chicks, 7-day-old chicks were exposed to cold temperature (4 °C) or kept warm (30 °C). Chicks exposed to the cold showed cardiac hypertrophy with marked left ventricular (LV) chamber dilation and wall thickening. On the other hand, long-term cold exposure (2 weeks from 7-day-old) induced an increase in total ventricular mass, but not in LV morphological parameters. Then, we investigated the details of acute cardiac hypertrophy in chicks. Electron microscopy revealed that cardiomyocytes in the hypertrophied LV had enlarged mitochondria with less dense cristae. Although the mRNA expression of lipoprotein lipase in the LV of the cold-exposed chicks significantly increased, the mRNA expression of genes involved in fatty acid β-oxidation did not change in response to cold exposure. In addition, the mRNA expression of peroxisome proliferator-activated receptor gamma coactivator-1 alpha, which enhances mitochondrial biogenesis and function under physiological cardiac hypertrophy, increased in LV of cold-exposed chicks. The study found that acute cold exposure to neonatal chicks induces LV hypertrophy. However, these results suggest that acute cold exposure to chicks might induce both adaptive and maladaptive responses of the LV. PMID:26733397

  16. Effect of chromium (VI) exposure on antioxidant defense status and trace element homeostasis in acute experiment in rat.

    PubMed

    Kotyzová, Dana; Hodková, Anna; Bludovská, Monika; Eybl, Vladislav

    2015-11-01

    Occupational exposure to hexavalent chromium (Cr(VI)) compounds is of concern in many Cr-related industries and their surrounding environment. Cr(VI) is a proven toxin and carcinogen. The Cr(VI) compounds are easily absorbed, can diffuse across cell membranes, and have strong oxidative potential. Despite intensive studies of Cr(VI) pro-oxidative effects, limited data exist on the influence of Cr(VI) on selenoenzymes thioredoxin reductase (TrxR) and glutathione peroxidase (GPx)-important components of antioxidant defense system. This study investigates the effect of Cr(VI) exposure on antioxidant defense status, with focus on these selenoenzymes, and on trace element homeostasis in an acute experiment in rat. Male Wistar rats (130-140g) were assigned to two groups of 8 animals: I. control; and II. Cr(VI) treated. The animals in Cr(VI) group were administered a single dose of K2Cr2O7 (20 mg /kg, intraperitoneally (ip)). The control group received saline solution. After 24 h, the animals were sacrificed and the liver and kidneys were examined for lipid peroxidation (LP; thiobarbituric acid reactive substances (TBARS) concentration), the level of reduced glutathione (GSH) and the activities of GPx-1, TrxR-1, and glutathione reductase (GR). Samples of tissues were also used to estimate Cr accumulation and alterations in zinc, copper, and iron levels. The acute Cr(VI) exposure caused an increase in both hepatic and renal LP (by 70%, p < 0.01 and by 15%, p < 0.05, respectively), increased hepatic GSH level and GPx-1 activity, and decreased renal GPx-1 activity. The activity of GR was not changed. A significant inhibitory effect of Cr(VI) was found on TrxR-1 activity in both the liver and the kidneys. The ability of Cr(VI) to cause TrxR inhibition could contribute to its cytotoxic effects. Further investigation of oxidative responses in different in vivo models may enable the development of strategies to protect against Cr(VI) oxidative damage. PMID:23625905

  17. Ultrastructural changes in the nasal mucosa of Fischer 344 rats and B6C3F1 mice following an acute exposure to methyl isocyanate

    SciTech Connect

    Uraih, L.C.; Talley, F.A.; Mitsumori, K.; Gupta, B.N.; Bucher, J.R.; Boorman, G.A.

    1987-06-01

    Male rats and male mice received a single 2-hr exposure to 0 (control), 10, or 30 ppm of methyl isocyanate and were sacrificed after 1, 3, 14, or 90 days to assess the ultrastructural changes in the nasal mucosa by transmission electron microscopy. One day after exposure to methyl isocyanate, there were widespread areas of necrosis and degeneration of the respiratory and olfactory epithelium of rats and mice in the 10 ppm and 30 ppm groups. Qualitatively the ultrastructural findings were similar for both exposure groups and species. Degeneration followed by rapid regeneration was observed for both respiratory and olfactory epithelia but was most striking for olfactory epithelium in the dorsal meatus. Three days after the exposure, the olfactory epithelium was two to three cell layers thick due to a loss of supporting cells, olfactory neurons, and basal cells. By 14 days after exposure, the olfactory epithelium was composed of a heterogeneous cell population three to five cell layers thick. At 90 days following exposure, the epithelium was of normal thickness (eight to ten cell layers), with normal architectural arrangement, and composed of well-differentiated cells that appeared similar to those of controls. There were several findings that suggested the epithelial cells of Bowman's glands were the progenitor for the regenerating supporting cells of the olfactory epithelium. This study demonstrated that the respiratory and olfactory epithelium is capable of complete structural regeneration after an acute destruction by methyl isocyanate.

  18. Association between ambient noise exposure, hearing acuity, and risk of acute occupational injury

    PubMed Central

    Cantley, Linda F; Galusha, Deron; Cullen, Mark R; Dixon-Ernst, Christine; Rabinowitz, Peter M; Neitzel, Richard L

    2015-01-01

    Objective This study aimed to examine the associations between acute workplace injury risk, ambient noise exposure, and hearing acuity, adjusting for reported hearing protection use. Methods In a cohort of 9220 aluminum manufacturing workers studied over six years (33 300 person-years, 13 323 person-jobs), multivariate mixed effects models were used to estimate relative risk (RR) of all injuries as well as serious injuries by noise exposure category and hearing threshold level (HTL) adjusting for recognized and potential confounders. Results Compared to noise <82 dBA, higher exposure was associated with elevated risk in a monotonic and statistically significant exposure–response pattern for all injuries and serious injuries with higher risk estimates observed for serious injuries [82–84.99 dBA: RR 1.26, 95% confidence interval (95% CI) 0.96–1.64; 85–87.99 dBA: RR 1.39, 95% CI 1.05–1.85; ≥88 dBA: RR 2.29, 95% CI 1.52–3.47]. Hearing loss was associated with increased risk for all injuries, but was not a significant predictor of risk for the subset of more serious injuries. Compared to those without hearing loss, workers with HTL ≥25 dB had 21% increased all injury risk (RR 1.21, 95% CI 1.09–1.33) while those with HTL 10–24.99 dB had 6% increased risk (RR 1.06, 95% CI 1.00–1.13). Reported hearing protection type did not predict injury risk. Conclusion Noise exposure levels as low as 85 dBA may increase workplace injury risk. HTL was associated with increased risk for all, but not the subset of serious, injuries. Additional study is needed both to confirm the observed associations and explore causal pathways. PMID:25137556

  19. Acute exposure to ethanol on gestational day 15 affects social motivation of female offspring.

    PubMed

    Varlinskaya, Elena I; Mooney, Sandra M

    2014-03-15

    Alterations in social behavior are a hallmark of many neurodevelopmental disorders in humans. In rodents, social behavior is affected by prenatal insults. The outcomes are dependent on the timing of the insult as well as the sex and age of the animal tested. The limbic system is particularly important for social behavior, and a peak of neurogenesis within this system occurs on gestational day (G)15. Neurons appear particularly vulnerable to ethanol insult around the time they become post-mitotic. We tested the hypothesis that acute exposure to ethanol on G15 would result in significant social behavior deficits. Accordingly, Long Evans pregnant females were injected with ethanol (2.9 g/kg) or an equivalent volume of saline on G15. Offspring were assessed in a modified social interaction test on postnatal day (P) 28, P42, or P75, i.e., during early adolescence, late adolescence, or young adulthood. Prenatal ethanol exposure decreased social investigation in P28 females and transformed social preference into social avoidance in 75-day-old females. Contact behavior, play fighting, and locomotor activity differed as a function of age, but were not significantly affected by ethanol exposure. Males demonstrated significantly more contact behavior and play fighting at P42 than at P28 or P70, whereas there were no age-related changes in females. Adult females showed more locomotor activity than adult males. Overall, prenatal ethanol exposure on G15 enhanced social anxiety in females, with these effects seen in adulthood only. PMID:24355753

  20. Tobacco Smoke Exposure and the Risk of Childhood Acute Lymphoblastic and Myeloid Leukemias by Cytogenetic Subtype

    PubMed Central

    Metayer, Catherine; Zhang, Luoping; Wiemels, Joseph L.; Bartley, Karen; Schiffman, Joshua; Ma, Xiaomei; Aldrich, Melinda C.; Chang, Jeffrey S.; Selvin, Steve; Fu, Cecilia H.; Ducore, Jonathan; Smith, Martyn T.; Buffler, Patricia A.

    2013-01-01

    Background Tobacco smoke contains carcinogens known to damage somatic and germ cells. We investigated the effect tobacco smoke on the risk of childhood acute lymphoblastic leukemia (ALL) and myeloid leukemia (AML), especially subtypes of pre-natal origin like ALL with translocation t(12;21) or high-hyperdiploidy (51–67 chromosomes). Methods We collected information on exposures to tobacco smoking before conception, during pregnancy, and after birth in 767 ALL cases, 135 AML cases, and 1,139 controls (1996–2008). Among cases, chromosome translocations, deletions, or aneuploidy were identified by conventional karyotype and fluorescence in-situ hybridization. Results Multivariable regression analyses for ALL and AML overall showed no definite evidence of associations with self-reported (yes/no) parental prenatal active smoking and child's passive smoking. However, children with history of paternal prenatal smoking combined with postnatal passive smoking had a 1.5-fold increased risk of ALL (95% CI: 1.01–2.23), compared to those without smoking history (ORs for pre- or postnatal smoking only were close to one). This joint effect was seen for B-cell precursor ALL with t(12;21) (OR=2.08; 95% CI: 1.04–4.16), but not high hyperdiploid B-cell ALL. Similarly, child's passive smoking was associated with an elevated risk of AML with chromosome structural changes (OR=2.76; 95% CI: 1.01–7.58), but not aneuploidy. Conclusions our data suggest that exposure to tobacco smoking before were associated with increased risks of childhood ALL and AML; and risks varied by timing of exposure (before and/or after birth) and cytogenetic subtype, based on imprecise estimates. Impact Parents should limit exposures to tobacco smoke before and after the child's birth. PMID:23853208

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

    PubMed

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

    2016-10-01

    The present study aimed to assess specific cognitive processes (cognitive control and time perception) and hemodynamic correlates using functional near-infrared spectroscopy (fNIRS) during acute and prolonged high-altitude exposure. Eleven male subjects were transported via helicopter and dropped at 14 272 ft (4 350 meters) of altitude where they stayed for 4 days. Cognitive tasks, involving a conflict task and temporal bisection task, were performed at sea level the week before ascending to high altitude, the day of arrival (D0), the second (D2) and fourth (D4) day at high altitude. Cortical hemodynamic changes in the prefrontal cortex (PFC) area were monitored with fNIRS at rest and during the conflict task. Results showed that high altitude impacts information processing in terms of speed and accuracy. In the early hours of exposure (D0), participants displayed slower reaction times (RT) and decision errors were twice as high. While error rate for simple spontaneous responses remained twice that at sea level, the slow-down of RT was not detectable after 2 days at high-altitude. The larger fNIRS responses from D0 to D2 suggest that higher prefrontal activity partially counteracted cognitive performance decrements. Cognitive control, assessed through the build-up of a top-down response suppression mechanism, the early automatic response activation and the post-error adjustment were not impacted by hypoxia. However, during prolonged hypoxic exposure the temporal judgments were underestimated suggesting a slowdown of the internal clock. A decrease in cortical arousal level induced by hypoxia could consistently explain both the slowdown of the internal clock and the persistence of a higher number of errors after several days of exposure. PMID:27262217

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

    PubMed

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

    2016-01-21

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

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

    NASA Astrophysics Data System (ADS)

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

    2016-01-01

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

  4. Oral Exposure to Phytomonas serpens Attenuates Thrombocytopenia and Leukopenia during Acute Infection with Trypanosoma cruzi

    PubMed Central

    da Silva, Rosiane V.; Malvezi, Aparecida D.; Augusto, Leonardo da Silva; Kian, Danielle; Tatakihara, Vera Lúcia H.; Yamauchi, Lucy M.; Yamada-Ogatta, Sueli F.; Rizzo, Luiz V.; Schenkman, Sergio; Pinge-Filho, Phileno

    2013-01-01

    Mice infected with Trypanosoma cruzi, the agent of Chagas disease, rapidly develop anemia and thrombocytopenia. These effects are partially promoted by the parasite trans-sialidase (TS), which is shed in the blood and depletes sialic acid from the platelets, inducing accelerated platelet clearance and causing thrombocytopenia during the acute phase of disease. Here, we demonstrate that oral immunization of C57BL/6 mice with Phytomonas serpens, a phytoflagellate parasite that shares common antigens with T. cruzi but has no TS activity, reduces parasite burden and prevents thrombocytopenia and leukopenia. Immunization also reduces platelet loss after intraperitoneal injection of TS. In addition, passive transfer of immune sera raised in mice against P. serpens prevented platelet clearance. Thus, oral exposure to P. serpens attenuates the progression of thrombocytopenia induced by TS from T. cruzi. These findings are not only important for the understanding of the pathogenesis of T. cruzi infection but also for developing novel approaches of intervention in Chagas disease. PMID:23844182

  5. Oral exposure to Phytomonas serpens attenuates thrombocytopenia and leukopenia during acute infection with Trypanosoma cruzi.

    PubMed

    da Silva, Rosiane V; Malvezi, Aparecida D; Augusto, Leonardo da Silva; Kian, Danielle; Tatakihara, Vera Lúcia H; Yamauchi, Lucy M; Yamada-Ogatta, Sueli F; Rizzo, Luiz V; Schenkman, Sergio; Pinge-Filho, Phileno

    2013-01-01

    Mice infected with Trypanosoma cruzi, the agent of Chagas disease, rapidly develop anemia and thrombocytopenia. These effects are partially promoted by the parasite trans-sialidase (TS), which is shed in the blood and depletes sialic acid from the platelets, inducing accelerated platelet clearance and causing thrombocytopenia during the acute phase of disease. Here, we demonstrate that oral immunization of C57BL/6 mice with Phytomonas serpens, a phytoflagellate parasite that shares common antigens with T. cruzi but has no TS activity, reduces parasite burden and prevents thrombocytopenia and leukopenia. Immunization also reduces platelet loss after intraperitoneal injection of TS. In addition, passive transfer of immune sera raised in mice against P. serpens prevented platelet clearance. Thus, oral exposure to P. serpens attenuates the progression of thrombocytopenia induced by TS from T. cruzi. These findings are not only important for the understanding of the pathogenesis of T. cruzi infection but also for developing novel approaches of intervention in Chagas disease. PMID:23844182

  6. Acute respiratory effects of exposure to diesel emissions in coal miners

    SciTech Connect

    Ames, R.G.; Attfield, M.D.; Hankinson, J.L.; Hearl, F.J.; Reger, R.B.

    1982-01-01

    A study was conducted to determine if acute respiratory effects, measured in terms of changes in forced vital capacity (FVC), forced expiratory volume in one second (FEV1), and maximal expiratory flow rate at 50% of forced vital capacity (Vmax50), were related to exposure to diesel emissions in coal miners. Sixty coal miners exposed to diesel emissions and 90 miners not exposed were tested before and after a work shift for ventilatory function changes. Significant work shift decrements in ventilatory function did occur in miners in both groups who smoked cigarettes, but there were no significant differences in the ventilatory function changes between those miners exposed to diesel emissions and those not exposed either in the aggregate or under control by smoking status.

  7. A single exposure to acrolein desensitizes baroreflex responsiveness and increases cardiac arrhythmias in normotensive and hypertensive rats

    EPA Science Inventory

    Background – Short-term exposure to air pollutants has been linked to acute cardiovascular morbidity and mortality. Even in the absence of overt symptoms, pollutants can cause subtle disruptions of internal regulatory mechanisms, which maintain homeostatic balance, thereby reduci...

  8. Research design considerations for single-dose analgesic clinical trials in acute pain: IMMPACT recommendations.

    PubMed

    Cooper, Stephen A; Desjardins, Paul J; Turk, Dennis C; Dworkin, Robert H; Katz, Nathaniel P; Kehlet, Henrik; Ballantyne, Jane C; Burke, Laurie B; Carragee, Eugene; Cowan, Penney; Croll, Scott; Dionne, Raymond A; Farrar, John T; Gilron, Ian; Gordon, Debra B; Iyengar, Smriti; Jay, Gary W; Kalso, Eija A; Kerns, Robert D; McDermott, Michael P; Raja, Srinivasa N; Rappaport, Bob A; Rauschkolb, Christine; Royal, Mike A; Segerdahl, Märta; Stauffer, Joseph W; Todd, Knox H; Vanhove, Geertrui F; Wallace, Mark S; West, Christine; White, Richard E; Wu, Christopher

    2016-02-01

    This article summarizes the results of a meeting convened by the Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials (IMMPACT) on key considerations and best practices governing the design of acute pain clinical trials. We discuss the role of early phase clinical trials, including pharmacokinetic-pharmacodynamic (PK-PD) trials, and the value of including both placebo and active standards of comparison in acute pain trials. This article focuses on single-dose and short-duration trials with emphasis on the perioperative and study design factors that influence assay sensitivity. Recommendations are presented on assessment measures, study designs, and operational factors. Although most of the methodological advances have come from studies of postoperative pain after dental impaction, bunionectomy, and other surgeries, the design considerations discussed are applicable to many other acute pain studies conducted in different settings. PMID:26683233

  9. Caffeine improves performance in double poling during acute exposure to 2,000-m altitude.

    PubMed

    Stadheim, H K; Nossum, E M; Olsen, R; Spencer, M; Jensen, J

    2015-12-15

    There is limited research on the physiological effects of caffeine (CAF) ingestion on exercise performance during acute hypoxia. The aim of the present study was therefore to test the effect of placebo (PLA) and CAF (4.5 mg/kg) on double poling (DP) performance during acute hypoxia. Thirteen male subelite cross-country skiers (V̇o2max 72.6 ± 5.68 ml·kg(-1)·min(-1)) were included. Performance was assessed as 1) an 8-km cross-country DP time-trial (C-PT), and 2) time until task failure at a set workload equal to ∼90% of DP V̇o2max. Testing was carried out in a hypobaric chamber, at 800 mbar (Pio2: ∼125 mmHg) corresponding to ∼2,000 m above sea level in a randomized double-blinded, placebo-controlled, cross-over design. CAF improved time to task failure from 6.10 ± 1.40 to 7.22 ± 1.30 min (P < 0.05) and velocity the first 4 km (P < 0.05) but not overall time usage for the 8-km C-PT. During submaximal exercise subjects reported lower pain in arms and rate of perceived exertion (RPE) following CAF ingestion. Throughout C-PTs similar RPE and pain was shown between treatments. However, higher heart rate was observed during the CAF 8 km (187 ± 7 vs. 185 ± 7; P < 0.05) and 90% C-PT (185 ± 7 vs. 181 ± 9) associated with increased ventilation, blood lactate, glucose, adrenaline, decreased pH, and bicarbonate. The present study demonstrates for the first time that CAF ingestion improves DP time to task failure although not consistently time trial performance during acute exposure to altitude. Mechanisms underpinning improvements seem related to reduced pain RPE and increased heart rate during CAF C-PTs. PMID:26494444

  10. Effect of acute exposure to moderate altitude on muscle power: hypobaric hypoxia vs. normobaric hypoxia.

    PubMed

    Feriche, Belén; García-Ramos, Amador; Calderón-Soto, Carmen; Drobnic, Franchek; Bonitch-Góngora, Juan G; Galilea, Pedro A; Riera, Joan; Padial, Paulino

    2014-01-01

    When ascending to a higher altitude, changes in air density and oxygen levels affect the way in which explosive actions are executed. This study was designed to compare the effects of acute exposure to real or simulated moderate hypoxia on the dynamics of the force-velocity relationship observed in bench press exercise. Twenty-eight combat sports athletes were assigned to two groups and assessed on two separate occasions: G1 (n = 17) in conditions of normoxia (N1) and hypobaric hypoxia (HH) and G2 (n = 11) in conditions of normoxia (N2) and normobaric hypoxia (NH). Individual and complete force-velocity relationships in bench press were determined on each assessment day. For each exercise repetition, we obtained the mean and peak velocity and power shown by the athletes. Maximum power (Pmax) was recorded as the highest P(mean) obtained across the complete force-velocity curve. Our findings indicate a significantly higher absolute load linked to P(max) (∼ 3%) and maximal strength (1 RM) (∼ 6%) in G1 attributable to the climb to altitude (P<0.05). We also observed a stimulating effect of natural hypoxia on P(mean) and P(peak) in the middle-high part of the curve (≥ 60 kg; P<0.01) and a 7.8% mean increase in barbell displacement velocity (P<0.001). No changes in any of the variables examined were observed in G2. According to these data, we can state that acute exposure to natural moderate altitude as opposed to simulated normobaric hypoxia leads to gains in 1 RM, movement velocity and power during the execution of a force-velocity curve in bench press. PMID:25474104

  11. Effect of Acute Exposure to Moderate Altitude on Muscle Power: Hypobaric Hypoxia vs. Normobaric Hypoxia

    PubMed Central

    Feriche, Belén; García-Ramos, Amador; Calderón-Soto, Carmen; Drobnic, Franchek; Bonitch- Góngora, Juan G.; Galilea, Pedro A.; Riera, Joan; Padial, Paulino

    2014-01-01

    When ascending to a higher altitude, changes in air density and oxygen levels affect the way in which explosive actions are executed. This study was designed to compare the effects of acute exposure to real or simulated moderate hypoxia on the dynamics of the force-velocity relationship observed in bench press exercise. Twenty-eight combat sports athletes were assigned to two groups and assessed on two separate occasions: G1 (n = 17) in conditions of normoxia (N1) and hypobaric hypoxia (HH) and G2 (n = 11) in conditions of normoxia (N2) and normobaric hypoxia (NH). Individual and complete force-velocity relationships in bench press were determined on each assessment day. For each exercise repetition, we obtained the mean and peak velocity and power shown by the athletes. Maximum power (Pmax) was recorded as the highest Pmean obtained across the complete force-velocity curve. Our findings indicate a significantly higher absolute load linked to Pmax (∼3%) and maximal strength (1RM) (∼6%) in G1 attributable to the climb to altitude (P<0.05). We also observed a stimulating effect of natural hypoxia on Pmean and Ppeak in the middle-high part of the curve (≥60 kg; P<0.01) and a 7.8% mean increase in barbell displacement velocity (P<0.001). No changes in any of the variables examined were observed in G2. According to these data, we can state that acute exposure to natural moderate altitude as opposed to simulated normobaric hypoxia leads to gains in 1RM, movement velocity and power during the execution of a force-velocity curve in bench press. PMID:25474104

  12. Abundance of plasma antioxidant proteins confers tolerance to acute hypobaric hypoxia exposure.

    PubMed

    Padhy, Gayatri; Sethy, Niroj Kumar; Ganju, Lilly; Bhargava, Kalpana

    2013-09-01

    Systematic identification of molecular signatures for hypobaric hypoxia can aid in better understanding of human adaptation to high altitude. In an attempt to identify proteins promoting hypoxia tolerance during acute exposure to high altitude, we screened and identified hypoxia tolerant and susceptible rats based on hyperventilation time to a simulated altitude of 32,000 ft (9754 m). The hypoxia tolerance was further validated by estimating 8-isoprotane levels and protein carbonyls, which revealed that hypoxia tolerant rats possessed significant lower plasma levels as compared to susceptible rats. We used a comparative plasma proteome profiling approach using 2-dimensional gel electrophoresis (2-DGE) combined with MALDI TOF/TOF for both groups, along with an hypoxic control group. This resulted in the identification of 19 differentially expressed proteins. Seven proteins (TTR, GPx-3, PON1, Rab-3D, CLC11, CRP, and Hp) were upregulated in hypoxia tolerant rats, while apolipoprotein A-I (APOA1) was upregulated in hypoxia susceptible rats. We further confirmed the consistent higher expression levels of three antioxidant proteins (PON1, TTR, and GPx-3) in hypoxia-tolerant animals using ELISA and immunoblotting. Collectively, these proteomics-based results highlight the role of antioxidant enzymes in conferring hypoxia tolerance during acute hypobaric hypoxia. The expression of these antioxidant enzymes could be used as putative biomarkers for screening altitude adaptation as well as aiding in better management of altered oxygen pathophysiologies. PMID:24067188

  13. Maternal metallothionein and zinc after acute ethanol exposure during gestation in the rat

    SciTech Connect

    Harris, J.E. )

    1992-02-26

    Acute exposure of the rat fetus to ethanol at critical periods can cause growth retardation and brain damage; the mechanism(s) is not known. Ethanol may cause redistribution of maternal zinc which results in fetal zinc deficiency and subsequent interruption of growth and development. The purpose was to determine if acute ethanol administration to the pregnant rat alters Zn and the Zn binding protein metallothionein (MT) in selected tissues. On gestational day (gd) 14, eighteen pregnant Sprague-Dawley rats were divided into groups. By intragastric tube, ethanol treated dams were given ethanol and pairfed controls were given a 0.85% NaCl solution. On gd 15, intragastric feedings were repeated. Throughout, the Lieber-DeCarli control diet was fed (adlibitum to untreated controls and ethanol treated dams and in appropriate quantities to pair fed controls). Blood ethanol concentrations at 90 minutes after the ethanol dose were 154 {plus minus} 46 and 265 {plus minus} 110 mg% on gd 14 and 15, respectively.

  14. Biophysical model for assessment of risk of acute exposures in combination with low level chronic irradiation

    NASA Astrophysics Data System (ADS)

    Smirnova, O. A.

    A biophysical model is developed which describes the mortality dynamics in mammalian populations unexposed and exposed to radiation The model relates statistical biometric functions mortality rate life span probability density and life span probability with statistical characteristics and dynamics of a critical body system in individuals composing the population The model describing the dynamics of thrombocytopoiesis in nonirradiated and irradiated mammals is also developed this hematopoietic line being considered as the critical body system under exposures in question The mortality model constructed in the framework of the proposed approach was identified to reproduce the irradiation effects on populations of mice The most parameters of the thrombocytopoiesis model were determined from the data available in the literature on hematology and radiobiology the rest parameters were evaluated by fitting some experimental data on the dynamics of this system in acutely irradiated mice The successful verification of the thrombocytopoiesis model was fulfilled by the quantitative juxtaposition of the modeling predictions and experimental data on the dynamics of this system in mice exposed to either acute or chronic irradiation at wide ranges of doses and dose rates It is important that only experimental data on the mortality rate in nonirradiated population and the relevant statistical characteristics of the thrombocytopoiesis system in mice which are also available in the literature on radiobiology are needed for the final identification of

  15. Acute effects of exposure to 1 mg/m(3) of vaporized 2-ethyl-1-hexanol in humans.

    PubMed

    Ernstgård, L; Norbäck, D; Nordquist, T; Wieslander, G; Wålinder, R; Johanson, G

    2010-04-01

    The objective was to assess acute effects from controlled exposure of volunteers to 2-ethyl-1-hexanol, a volatile organic compound that is often found in indoor air. Sixteen males and fourteen females were in random order exposed to 1 mg/m(3) of vapors of 2-ethyl-1-hexanol or to clean air (control exposure) in an exposure chamber during 2 h at rest. The subjects performed symptom ratings on Visual Analog Scales. During exposure to 2-ethyl-1-hexanol subjective ratings of smell and eye discomfort were minimally but significantly increased. Ratings of nasal irritation, throat irritation, headache, dyspnoea, fatigue, dizziness, nausea, and intoxication were not significantly affected. No exposure-related effects on measurement of blinking frequency by electromyography, measurement of the eye break-up time, vital staining of the eye, nasal lavage biomarkers, transfer tests, spirometric and rhinometric measures were seen. No differences in response were seen between sexes or between atopics and non-atopics. Practical Implications It is important to assess acute effects in volatile organic compounds like 2-ethyl-1-hexanol. 2-ethyl-1-hexanol is often found in indoor air generated by degradation of plastic building materials or in new buildings. There are associations between 2-ethyl-1-hexanol in indoor air and respiratory effects, eye irritation, headache, and blurred vision. A controlled chamber exposure study in acute effects was performed. In conclusion, this study showed weak subjective symptom of irritation in the eyes. PMID:20409194

  16. Studies on acute in vivo exposure of rats to 2450-MHz microwave radiation. III. Biochemical and hematologic effects

    SciTech Connect

    Galvin, M.J.; Ortner, M.J.; McRee, P.I.

    1982-06-01

    Male rats were exposed to 2450-MHz cw microwave radiation for 8 hr at incident power densities of 0 (sham), 2, or 10 mW/cm/sup 2/. Following exposure, rats were killed by decapitation, and blood samples were collected for determination of hematocrit, hemoglobin, red and white cell count, and differential white cell percentages. The total red and white cell counts were not affected by either exposure level. The blood hemoglobin level was also unaffected by the 8-hr microwave exposure, having a value of approximately 15.5 g% for all three groups. The percentages of lymphocytes and neutrophils for both exposed groups was similar to those of the sham group. The other cell types were also unchanged by the microwave exposure. None of the serum biochemistries examined were affected by either microwave exposure level. These data therefore demonstrate that acute (8 hr) exposure to 2450-MHz cw microwave radiation has no effect on the hematologic and biochemical parameters examined.

  17. Nef gene evolution from a single transmitted strain in acute SIV infection

    PubMed Central

    Bimber, Benjamin N; Chugh, Pauline; Giorgi, Elena E; Kim, Baek; Almudevar, Anthony L; Dewhurst, Stephen; O'Connor, David H; Lee, Ha Youn

    2009-01-01

    Background The acute phase of immunodeficiency virus infection plays a crucial role in determining steady-state virus load and subsequent progression of disease in both humans and nonhuman primates. The acute period is also the time when vaccine-mediated effects on host immunity are likely to exert their major effects on virus infection. Recently we developed a Monte-Carlo (MC) simulation with mathematical analysis of viral evolution during primary HIV-1 infection that enables classification of new HIV-1 infections originating from multiple versus single transmitted viral strains and the estimation of time elapsed following infection. Results A total of 322 SIV nef SIV sequences, collected during the first 3 weeks following experimental infection of two rhesus macaques with the SIVmac239 clone, were analyzed and found to display a comparable level of genetic diversity, 0.015% to 0.052%, with that of env sequences from acute HIV-1 infection, 0.005% to 0.127%. We confirmed that the acute HIV-1 infection model correctly identified the experimental SIV infections in rhesus macaques as "homogenous" infections, initiated by a single founder strain. The consensus sequence of the sampled strains corresponded to the transmitted sequence as the model predicted. However, measured sequential decrease in diversity at day 7, 11, and 18 post infection violated the model assumption, neutral evolution without any selection. Conclusion While nef gene evolution over the first 3 weeks of SIV infection originating from a single transmitted strain showed a comparable rate of sequence evolution to that observed during acute HIV-1 infection, a purifying selection for the founder nef gene was observed during the early phase of experimental infection of a nonhuman primate. PMID:19505314

  18. Single-leg drop landing motor control strategies following acute ankle sprain injury.

    PubMed

    Doherty, C; Bleakley, C; Hertel, J; Caulfield, B; Ryan, J; Delahunt, E

    2015-08-01

    No research currently exists investigating the effect of acute injury on single-limb landing strategies. The aim of the current study was to analyze the coordination strategies of participants in the acute phase of lateral ankle sprain (LAS) injury. Thirty-seven participants with acute, first-time LAS and 19 uninjured participants completed a single-leg drop landing task on both limbs. Three-dimensional kinematic (angular displacement) and sagittal plane kinetic (moment-of-force) data were acquired for the joints of the lower extremity from 200 ms pre-initial contact (IC) to 200 ms post-IC. The peak magnitude of the vertical component of the ground reaction force (GRF) was also computed. Injured participants displayed a bilateral increase in hip flexion, with altered transverse plane kinematic profiles at the knee and ankle for both limbs (P < 0.05). This coincided with a reduction in the net-supporting flexor moment of the lower extremity (P < 0.05) and magnitude of the peak vertical GRF for the injured limb (21.82 ± 2.44 N/kg vs 24.09 ± 2.77 N/kg; P = 0.013) in injured participants compared to control participants. These results demonstrate that compensatory movement strategies are utilized by participants with acute LAS to successfully reduce the impact forces of landing. PMID:24975875

  19. [Effect of training on treadmill performance, aerobic capacity and body reactions to acute cold exposure].

    PubMed

    Iakushkin, A V; Akimov, E B; Andreev, R S; Kalenov, Iu N; Kozlov, A V; Kuznetsova, O V; Son'kin, V D

    2014-01-01

    An attempt was made to test the hypothesis that regular physical activity at the anaerobic threshold is able to stimulate an increase in the amount of body fat brown or beige, which can manifest itself in increasing lactate utilization during exercise and increase the reactivity in response to acute regional cooling. The methods used are: ramp test, regional acute cold exposure, measurement of gas exchange, lactate and glucose in the blood, heart rate, and heart rate variability, blood pressure and respiration variability at rest and during standard functional tests; infrared thermal imaging, statistical methods of results analysis. Workout 10 physically active volunteers (7 males and 3 females) on a treadmill at a speed corresponding to 75-80% of the persona VO2max for 30 minutes 3 times per week at a fixed ambient temperature 21-22°C for 6 weeks resulted in a significant (from 19 to 39%) increase in test work duration but VO2max on average changed little. The increase in power of anaerobic threshold was associated with a sharp slowdown in the accumulation of lactate in progress of ramp test. Lactate utilization rate during the recovery period, on the contrary, increased. In general, significantly increased work efficiency at a test load. Not revealed noticeable changes in the condition and response to a standard functional tests of autonomic systems, as judged by heart rate variability, blood pressure and respiration variability at rest and during orthostatic tests and imposed breathing rhythm. The functional response of the body to acute cold exposure (1 minute cooling of the feet in ice water) is not changed after a cycle of training--either in terms of metabolism (oxygen consumption, etc.), or the dynamics of the skin temperature in areas of most probable location of brown adipose tissue (BAT). These data do not confirm the previously expressed (2010) hypothesis about the function of BAT as a universal homeostatic instrument in the body. Probably, if under

  20. Acute cocaine exposure alters spine density and long-term potentiation in the ventral tegmental area.

    PubMed

    Sarti, Federica; Borgland, Stephanie L; Kharazia, Viktor N; Bonci, Antonello

    2007-08-01

    Growing evidence indicates that the expression of synaptic plasticity in the central nervous system results in dendritic reorganization and spine remodeling. Although long-term potentiation of glutamatergic synapses after cocaine exposure in the ventral tegmental area (VTA) has been proposed as a cellular mechanism underlying addictive behaviors, the relationship between long-term potentiation and dendritic remodeling induced by cocaine on the dopaminergic neurons of the VTA has not been demonstrated. Here we report that rat VTA cells classified as type I and II showed distinct morphological responses to cocaine, as a single cocaine exposure significantly increased dendritic spine density in type I but not in type II cells. Further, only type I cells had a significant increase in the AMPA receptor:NMDA receptor ratio after a single cocaine exposure. Taken together, our data provide evidence that increased spine density and synaptic plasticity are coexpressed within the same VTA neuronal population and that only type I neurons are structurally and synaptically modified by cocaine. PMID:17686047

  1. Acute exposure to 2G phase shifts the rat circadian timing system

    NASA Technical Reports Server (NTRS)

    Hoban-Higgins, T. M.; Murakami, D. M.; Tandon, T.; Fuller, C. A.

    1995-01-01

    The circadian timing system (CTS) provides internal and external temporal coordination of an animal's physiology and behavior. In mammals, the generation and coordination of these circadian rhythms is controlled by a neural pacemaker, the suprachiasmatic nucleus (SCN), located within the hypothalamus. The pacemaker is synchronized to the 24 hour day by time cures (zeitgebers) such as the light/dark cycle. When an animal is exposed to an environment without time cues, the circadian rhythms maintain internal temporal coordination, but exhibit a 'free-running' condition in which the period length is determined by the internal pacemaker. Maintenance of internal and external temporal coordination are critical for normal physiological and psychological function in human and non-human primates. Exposure to altered gravitational environments has been shown to affect the amplitude, mean, and timing of circadian rhythms in species ranging from unicellular organisms to man. However, it has not been determined whether altered gravitational fields have a direct effect on the neural pacemaker, or affect peripheral parameters. In previous studies, the ability of a stimulus to phase shift circadian rhythms was used to determine whether a stimulus has a direct effect on the neural pacemaker. The present experiment was performed in order to determine whether acute exposure to a hyperdynamic field could phase shift circadian rhythms.

  2. Acute effects of exposure to air contaminants in a sawmill on healthy volunteers.

    PubMed Central

    Dahlqvist, M; Palmberg, L; Malmberg, P; Sundblad, B M; Ulfvarson, U; Zhiping, W

    1996-01-01

    OBJECTIVES: To study whether air contaminants in sawmills can induce acute changes in the upper and lower airways of previously non-exposed subjects. METHODS: Nineteen healthy volunteers were examined to find the concentration of interleukin 6 (IL-6) in nasal lavage fluid and lung function before and after five hour exposure to dusts and fumes generated in a sawmill where timber from Scots pine was sawed. When exposed, the subjects had respirators with and without a particle filter. RESULTS: The median for daily time weighted average concentration of total dust for subjects with respirators without a filter was 0.13 mg/m3, which was significantly higher than the median of 0.04 mg/m3 for subjects who had respirators with a filter. The median for the concentration of IL-6 in the nasal lavage fluid increased after exposure from 0.5 to 5.9 pg/ml in subjects with respirators without a particle filter (P < 0.05). The increase of the concentration of IL-6 was significantly correlated with the dust concentration. A decrease in transfer factor of the lung was significantly correlated with daily time weighted average concentrations of terpenes. CONCLUSION: The findings suggest that healthy volunteers, exposed to air contaminants in a sawmill, show a slight inflammatory reaction. Also, the results of the study indicate the importance of decreasing the concentrations of wood dust in the work environment. PMID:8882114

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

    PubMed

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

    2013-01-01

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

  4. Acute effects of exposure to orthochlorobenzylidene malononitrile (CS) and the development of tolerance

    PubMed Central

    Beswick, F. W.; Holland, P.; Kemp, K. H.

    1972-01-01

    Beswick, F. W., Holland, P., and Kemp, K. H. (1972).Brit. J. industr. Med.,29, 298-306. Acute effects of exposure to orthochlorobenzylidene malononitrile (CS) and the development of tolerance. Of the many compounds capable of producing irritation of the eyes and upper respiratory tract two, ω-chloroacetophenone and orthochlorobenzylidene malononitrile (CS), have been used as riot control agents. The latter, CS, has been in use for more than 10 years and is currently still in service. When dispersed as a smoke consisting of 1-micron diameter particles CS will produce lachrymation and pain and discomfort in the upper respiratory tract and chest. Exposed individuals become apprehensive and highly motivated to escape from the smoke. Recovery from these effects occurs within minutes of the affected individual reaching fresh air. The present study reports the effects produced by CS aerosol on 35 healthy male volunteers who were exposed in such a way that the total dose of the agent received by each man was greater than that which he might have received in an actual riot; this was achieved by taking advantage of the fact that adaptation to the effects of CS occurs if exposure is gradual and to low concentrations. In addition to the clinical observations, cardiological, respiratory, and biochemical observations were made. No abnormalities were observed in the electrocardiogram, respiratory function tests or the blood biochemistry and cell constitution. Such changes that were observed could be ascribed to the emotional stress and discomfort of the experiment. PMID:5044601

  5. ASSESSMENT OF THE HEPATOTOXICITY OF ACUTE AND SHORT-TERM EXPOSURE TO INHALED P-XYLENE IN F-344 RATS

    EPA Science Inventory

    Because of the ubiquitous presence of p-xylene in air and the existing uncertainty regarding its hepatotoxic potential, we examined the effect of acute and short-term exposure to Inhaled p-xylene on the liver. ale F344 rats were exposed to 0 or to 1600 ppm p-xylene, 6 hr/day, for...

  6. Acute Exposure to Stress Improves Performance in Trace Eyeblink Conditioning and Spatial Learning Tasks in Healthy Men

    ERIC Educational Resources Information Center

    Duncko, Roman; Cornwell, Brian; Cui, Lihong; Merikangas, Kathleen R.; Grillon, Christian

    2007-01-01

    The present study investigated the effects of acute stress exposure on learning performance in humans using analogs of two paradigms frequently used in animals. Healthy male participants were exposed to the cold pressor test (CPT) procedure, i.e., insertion of the dominant hand into ice water for 60 sec. Following the CPT or the control procedure,…

  7. EFFECTS OF ACUTE EXPOSURE TO CONCENTRATED AMBIENT PARTICULATES ON CARDIOPULMONARY, THERMOREGULATORY, AND BIOCHEMICAL PARAMETERS IN OLD SPONTANEOUSLY HYPERTENSIVE RATS

    EPA Science Inventory


    EFFECTS OF ACUTE EXPOSURE TO CONCENTRATED AMBIENT PARTICULATES ON CARDIOPULMONARY, THERMOREGULATORY, AND BIOCHEMICAL PARAMETERS IN OLD SPONTANEOUSLY HYPERTENSIVE RATS. JP Nolan1, LB Wichers2, DW Winsett1, UP Kodavanti1, MCJ Schladweiler1, DL Costa1, and WP Watkinson1. 1US E...

  8. Acute stress exposure preceding transient global brain ischemia exacerbates the decrease in cortical remodeling potential in the rat retrosplenial cortex.

    PubMed

    Kutsuna, Nobuo; Yamashita, Akiko; Eriguchi, Takashi; Oshima, Hideki; Suma, Takeshi; Sakatani, Kaoru; Yamamoto, Takamitsu; Yoshino, Atsuo; Katayama, Yoichi

    2014-01-01

    Doublecortin (DCX)-immunoreactive (-ir) cells are candidates that play key roles in adult cortical remodeling. We have previously reported that DCX-ir cells decrease after stress exposure or global brain ischemia (GBI) in the cingulate cortex (Cg) of rats. Herein, we investigate whether the decrease in DCX-ir cells is exacerbated after GBI due to acute stress exposure preconditioning. Twenty rats were divided into 3 groups: acute stress exposure before GBI (Group P), non-stress exposure before GBI (Group G), and controls (Group C). Acute stress or GBI was induced by a forced swim paradigm or by transient bilateral common carotid artery occlusion, respectively. DCX-ir cells were investigated in the anterior cingulate cortex (ACC) and retrosplenial cortex (RS). The number of DCX-ir cells per unit area (mm(2)) decreased after GBI with or without stress preconditioning in the ACC and in the RS (ANOVA followed by a Tukey-type test, P<0.001). Moreover, compared to Group G, the number in Group P decreased significantly in RS (P<0.05), though not significantly in ACC. Many of the DCX-ir cells were co-localized with the GABAergic neuronal marker parvalbumin. The present study indicates that cortical remodeling potential of GABAergic neurons of Cg decreases after GBI, and moreover, the ratio of the decrease is exacerbated by acute stress preconditioning in the RS. PMID:24257103

  9. Altered Hippocampal Lipid Profile Following Acute Postnatal Exposure to Di(2-Ethylhexyl) Phthalate in Rats

    PubMed Central

    Smith, Catherine A.; Farmer, Kyle; Lee, Hyunmin; Holahan, Matthew R.; Smith, Jeffrey C.

    2015-01-01

    Slight changes in the abundance of certain lipid species in the brain may drastically alter normal neurodevelopment via membrane stability, cell signalling, and cell survival. Previous findings have demonstrated that postnatal exposure to di (2-ethylhexyl) phthalate (DEHP) disrupts normal axonal and neural development in the hippocampus. The goal of the current study was to determine whether postnatal exposure to DEHP alters the lipid profile in the hippocampus during postnatal development. Systemic treatment with 10 mg/kg DEHP during postnatal development led to elevated levels of phosphatidylcholine and sphingomyelin in the hippocampus of female rats. There was no effect of DEHP exposure on the overall abundance of phosphatidylcholine or sphingomyelin in male rats or of lysophosphatidylcholine in male or female rats. Individual analyses of each identified lipid species revealed 10 phosphatidylcholine and six sphingomyelin lipids in DEHP-treated females and a single lysophosphatidylcholine in DEHP-treated males with a two-fold or higher increase in relative abundance. Our results are congruent with previous work that found that postnatal exposure to DEHP had a near-selective detrimental effect on hippocampal development in males but not females. Together, results suggest a neuroprotective effect of these elevated lipid species in females. PMID:26516880

  10. Altered Hippocampal Lipid Profile Following Acute Postnatal Exposure to Di(2-Ethylhexyl) Phthalate in Rats.

    PubMed

    Smith, Catherine A; Farmer, Kyle; Lee, Hyunmin; Holahan, Matthew R; Smith, Jeffrey C

    2015-10-01

    Slight changes in the abundance of certain lipid species in the brain may drastically alter normal neurodevelopment via membrane stability, cell signalling, and cell survival. Previous findings have demonstrated that postnatal exposure to di (2-ethylhexyl) phthalate (DEHP) disrupts normal axonal and neural development in the hippocampus. The goal of the current study was to determine whether postnatal exposure to DEHP alters the lipid profile in the hippocampus during postnatal development. Systemic treatment with 10 mg/kg DEHP during postnatal development led to elevated levels of phosphatidylcholine and sphingomyelin in the hippocampus of female rats. There was no effect of DEHP exposure on the overall abundance of phosphatidylcholine or sphingomyelin in male rats or of lysophosphatidylcholine in male or female rats. Individual analyses of each identified lipid species revealed 10 phosphatidylcholine and six sphingomyelin lipids in DEHP-treated females and a single lysophosphatidylcholine in DEHP-treated males with a two-fold or higher increase in relative abundance. Our results are congruent with previous work that found that postnatal exposure to DEHP had a near-selective detrimental effect on hippocampal development in males but not females. Together, results suggest a neuroprotective effect of these elevated lipid species in females. PMID:26516880

  11. Opposite effects of acute ethanol exposure on GAP-43 and BDNF expression in the hippocampus versus the cerebellum of juvenile rats

    PubMed Central

    Kulkarny, V.V.; Wiest, N. E; Marquez, C.P.; Nixon, S. C.; Valenzuela, C.F.; Perrone-Bizzozero, N.I.

    2011-01-01

    The adolescent brain is particularly vulnerable to the effects of alcohol, with intoxications at this developmental age often producing long-lasting effects. The present study addresses the effects of a single acute ethanol exposure on GAP-43 and BDNF gene expression in neurons in the cerebellum and hippocampus of adolescent rats. Male postnatal day 23 (P23) Sprague-Dawley rats were exposed to ethanol vapors for two hours and after a recovery period of two hours, the cerebellum and hippocampus were harvested and samples were taken for blood alcohol concentration (BAC) determinations. We found that this exposure resulted in a mean BAC of 174 mg/dl, which resembles levels in human adolescents after binge drinking. Analyses of total RNA and protein by qRT-PCR and western blotting, respectively, revealed that this single ethanol exposure significantly decreased the levels of GAP-43 mRNA and protein in the cerebellum but increased the levels of mRNA and protein in the hippocampus. BDNF mRNA and protein levels were also increased in the hippocampus but not in the cerebellum of these animals. In situ hybridizations revealed that GAP-43 and BDNF mRNA levels were primarily increased by alcohol exposure in hippocampal dentate granule cells and CA3 neurons. Overall, the reported alterations in the expression of the plasticity-associated genes GAP-43 and BDNF in juvenile rats are consistent with the known deleterious effects of binge drinking on motor coordination and cognitive function. PMID:21367572

  12. Household pesticide exposure and the risk of childhood acute leukemia in Shanghai, China.

    PubMed

    Zhang, Yan; Gao, Yu; Shi, Rong; Chen, Didi; Wang, Xiaojin; Kamijima, Michihiro; Sakai, Kiyoshi; Nakajima, Tamie; Khalequzzaman, Md; Zhou, Yijun; Zheng, Ying; Bao, Pingping; Tian, Ying

    2015-08-01

    Childhood acute leukemia (AL) is the most common malignant tumor in children, but its etiology remains largely unknown. We investigated the relationship between household exposure to pesticides and childhood AL. Between 2009 and 2010 in Shanghai, a total of 248 newly diagnosed cases of AL and 111 gender-, age-, and hospital-matched controls were included. Five nonspecific dialkyl phosphate (DAP) metabolites of organophosphate pesticides (OPPs) [including dimethyl phosphate (DMP), diethyl phosphate (DEP), dimethyl thiophosphate (DMTP), diethyl thiophosphate (DETP), and diethyl dithiophosphate (DEDTP)] in the urine were analyzed by gas chromatography. The results showed that the median DMP, DEP, DMTP, DETP, and DEDEP levels adjusted for creatinine (Cr) in cases (13.2, 10.0, 31.3, 8.5, and 6.1 μg g(-1), respectively) were all significantly elevated compared with those in controls (3.6, 3.6, 13.3, 2.7, and 1.7 μg g(-1), respectively) (P < 0.05). The household use of mosquito repellent was significantly associated with an increased risk of childhood AL (odds ratio (OR) = 1.9; 95% confidence interval (CI) 1.2-3.1). Moreover, higher exposures were significantly associated with an elevated risk of childhood AL for DMs, DEs, and DAPs. Our findings support the notion that the household use of pesticides may play a role in the etiology of childhood AL and provide some evidence to warrant further investigation of the link between household pesticide exposures and childhood AL in Shanghai. PMID:25854207

  13. [Exposure to tobacco smoke and type of acute respiratory infections in children].

    PubMed

    Bielska, Dorota; Trofimiuk, Emil; Ołdak, Elzbieta; Cylwik, Bogdan; Chlabicz, Sławomir

    2010-01-01

    Respiratory diseases are the most common cause of the child and family practice physicians are one of the main reasons for referral to a specialist clinic and hospital pediatric wards. The severity of respiratory disease in adolescence influenced by various factors, endo- and exogenous. Some of them, especially environmental factors can be eliminated or reduced and thus reduce the risk of developing this disease. The most common source of pollutants in dwellings is tobacco smoke. The aim of this study was to assess exposure to tobacco smoke in three years old children of attending local kindergartens in Białystok and its influence on the type of recovery from acute respiratory infections by the respondents. The study included 313 children from among the 1,200 who attend the local 51-kindergartens in Bialystok. Information on the structure of tobacco use in three-years-old-children's families and respiratory illnesses among random children were obtained, based on anonymous questionnaires completed by their carers. Exposure to tobacco smoke was based on questionnaires and serum cotinine in relation to creatinine in the urine of patients (K/K). In the 150 families surveyed children found 210 smoking people. Every day smoked 37.3% of fathers and 23.6% of mothers. Of the children surveyed--34% of the houses which where there was a prohibition on tobacco use, 35% of the houses which were smoked in enclosed areas, in 31% of homes have not been established no-smoking rules. Children who during the six-month period to attend kindergarten gone lower respiratory tract infection had mean K/K (59.57 ng/mg) higher than the ones that were healthy and underwent upper respiratory tract infection. Used by the parents of the children tested in part to reduce the exposure to tobacco smoke in the home environment was ineffective and did not influence the decrease in the incidence of lower respiratory tract. PMID:21360910

  14. Modeling the acute health effects of astronauts from exposure to large solar particle events.

    PubMed

    Hu, Shaowen; Kim, Myung-Hee Y; McClellan, Gene E; Cucinotta, Francis A

    2009-04-01

    Radiation exposure from Solar Particle Events (SPE) presents a significant health concern for astronauts for exploration missions outside the protection of the Earth's magnetic field, which could impair their performance and result in the possibility of failure of the mission. Assessing the potential for early radiation effects under such adverse conditions is of prime importance. Here we apply a biologically based mathematical model that describes the dose- and time-dependent early human responses that constitute the prodromal syndromes to consider acute risks from SPEs. We examine the possible early effects on crews from exposure to some historically large solar events on lunar and/or Mars missions. The doses and dose rates of specific organs were calculated using the Baryon radiation transport (BRYNTRN) code and a computerized anatomical man model, while the hazard of the early radiation effects and performance reduction were calculated using the Radiation-Induced Performance Decrement (RIPD) code. Based on model assumptions we show that exposure to these historical events would cause moderate early health effects to crew members inside a typical spacecraft or during extra-vehicular activities, if effective shielding and medical countermeasure tactics were not provided. We also calculate possible even worse cases (double intensity, multiple occurrences in a short period of time, etc.) to estimate the severity, onset and duration of various types of early illness. Uncertainties in the calculation due to limited data on relative biological effectiveness and dose-rate modifying factors for protons and secondary radiation, and the identification of sensitive sites in critical organs are discussed. PMID:19276707

  15. Evaluating the acute effects of oral, non-combustible potential reduced exposure products marketed to smokers

    PubMed Central

    Cobb, CO; Weaver, MF; Eissenberg, T

    2011-01-01

    Background Non-combustible potential reduced exposure products (PREPs; eg, Star Scientific’s Ariva; a variety of other smokeless tobacco products) are marketed to reduce the harm associated with smoking. This marketing occurs despite an absence of objective data concerning the toxicant exposure and effects of these PREPs. Methods used to examine combustible PREPs were adapted to assess the acute effects of non-combustible PREPs for smokers. Methods 28 overnight abstinent cigarette smokers (17 men, 14 non-white) each completed seven, Latin-squared ordered, approximately 2.5 h laboratory sessions that differed by product administered: Ariva, Marlboro Snus (Philip Morris, USA), Camel Snus (RJ Reynolds, Winston-Salem, North Carolina, USA), Commit nicotine lozenge (GlaxoSmithKline; 2 mg), own brand cigarettes, Quest cigarettes (Vector Tobacco; delivers very low levels of nicotine) and sham smoking (ie, puffing on an unlit cigarette). In each session, the product was administered twice (separated by 60 min), and plasma nicotine levels, expired air CO and subjective effects were assessed regularly. Results Non-combustible products delivered less nicotine than own brand cigarettes, did not expose smokers to CO and failed to suppress tobacco abstinence symptoms as effectively as combustible products. Conclusions While decreased toxicant exposure is a potential indicator of harm reduction potential, a failure to suppress abstinence symptoms suggests that currently marketed non-combustible PREPs may not be a viable harm reduction strategy for US smokers. This study demonstrates how clinical laboratory methods can be used to evaluate the short-term effects of non-combustible PREPs for smokers. PMID:19346218

  16. Gene expression profiles in zebrafish (Danio rerio) liver after acute exposure to okadaic acid.

    PubMed

    Zhang, Nai-sheng; Li, Hong-ye; Liu, Jie-sheng; Yang, Wei-dong

    2014-03-01

    Okadaic acid (OA), a main component of diarrheic shellfish poisoning (DSP) toxins, is a strong and specific inhibitor of the serine/threonine protein phosphatases PP1 and PP2A. However, not all of the OA-induced effects can be explained by this phosphatase inhibition, and controversial results on OA are increasing. To provide clues on potential mechanisms of OA other than phosphatase inhibition, here, acute toxicity of OA was evaluated in zebrafish, and changes in gene expression in zebrafish liver tissues upon exposure to OA were observed by microarray. The i.p. ED50 (6 h) of OA on zebrafish was 1.54 μg OA/g body weight (bw). Among the genes analyzed on the zebrafish array, 55 genes were significantly up-regulated and 36 down-regulated in the fish liver tissue upon exposure to 0.176 μg OA/g bw (low-dose group, LD) compared with the low ethanol control (LE). However, there were no obvious functional clusters for them. On the contrary, fish exposure to 1.760 μg OA/g bw (high-dose group, HD) yielded a great number of differential expressed genes (700 up and 285 down) compared with high ethanol control (HE), which clustered in several functional terms such as p53 signaling pathway, Wnt signaling pathway, glutathione metabolism and protein processing in endoplasmic reticulum, etc. These genes were involved in protein phosphatase activity, translation factor activity, heat shock protein binding, as well as transmembrane transporter activity. Our findings may give some useful information on the pathways of OA-induced injury in fish. PMID:24637248

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

    PubMed

    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

  18. Direct observation of von Willebrand factor elongation and fiber formation on collagen during acute whole blood exposure to pathological flow

    PubMed Central

    Colace, T. V.; Diamond, S. L.

    2013-01-01

    Objective In severe stenosis, von Willebrand Factor (vWF) experiences millisecond exposures to pathological wall shear rates (γw). We sought to evaluate the deposition of vWF onto collagen surfaces under flow in these environments. Methods and Results Distinct from shear experiments that last many seconds, we deployed microfluidic devices for single-pass perfusion of whole blood or platelet free plasma (PFP) over fibrillar type 1 collagen (< 50 msec transit time) at pathological γw or spatial wall shear rate gradient (grad γw). Using fluorescent anti-vWF, long thick vWF fibers (>20 μm) bound to collagen were visualized at constant γw > 30,000 s−1 during perfusion of PFP, a process enhanced by EDTA. Rapid acceleration or deceleration of EDTA-PFP at grad γw = ± 5.5 × 105 to 4.3 × 107 s−1/cm did not promote vWF deposition. At 19,400 s−1, EDTA-blood perfusion resulted in rolling vWF-platelet nets, while blood perfusion (normal Ca2+) generated large vWF/platelet deposits that repeatedly embolized and were blocked by anti-GPIb or the α IIbβ3 inhibitor GR144053 and did not require grad γw. Blood perfusion at venous shear rate (200 s−1) produced a stable platelet deposit that was a substrate for massive but unstable vWF-platelet aggregates when flow was increased to 7800 s−1. Conclusion Triggered by collagen and enhanced by platelet GPIb and α IIbβ3, vWF fiber formation occurred during acute exposures to pathological γw and did not require gradients in wall shear rate. PMID:23104847

  19. Characterization and response of antioxidant systems in the tissues of the freshwater pond snail (Lymnaea stagnalis) during acute copper exposure.

    PubMed

    Atli, Gülüzar; Grosell, Martin

    2016-07-01

    The response of enzymatic (superoxide dismutase, SOD; catalase, CAT; glutathione peroxidase, GPX and glutathione reductase, GR) and non-enzymatic responses (glutathione, GSH, oxidized glutathione, GSSG and GSH/GSSG) against acute Cu toxicity (2-90μg/mL for 48h) in different tissues of Lymnaea stagnalis were measured. Incubation conditions for enzymatic activity measurements were optimized for L. stagnalis tissues. Three examined tissues, the hepatopancreas, the foot muscle and the mantle, exhibited variable responses in antioxidant parameters as a function of Cu concentrations. The most responsive antioxidant enzymes were GPX and CAT while GR appeared less sensitive. In general antioxidant enzymes at higher Cu concentrations though GSH levels at lower Cu concentrations exhibited the greatest changes in hepatopancreas and foot muscle, respectively. All antioxidant enzymes except GR increased after exposure to the highest Cu concentration in mantle. Total and reduced GSH increased in hepatopancreas but decreased with GSH/GSSG ratios at all Cu concentrations in foot muscle. The present results show that antioxidants respond to acute Cu exposure at concentrations as low as 2μg Cu/L in adult L. stagnalis with variable responses in different tissues. Antioxidants both including enzymatic and non-enzymatic parameters may account, in part, for the high tolerance to acute metal exposure observed in adult L. stagnalis and could form suited biomarkers to evaluate the metal exposure and toxicity in aquatic environment even at relatively low level short term exposure. PMID:27108202

  20. Early Life Arsenic Exposure and Acute and Long-term Responses to Influenza A Infection in Mice

    PubMed Central

    Foong, Rachel E.; Sly, Peter D.; Larcombe, Alexander N.; Zosky, Graeme R.

    2013-01-01

    Background: Arsenic is a significant global environmental health problem. Exposure to arsenic in early life has been shown to increase the rate of respiratory infections during infancy, reduce childhood lung function, and increase the rates of bronchiectasis in early adulthood. Objective: We aimed to determine if early life exposure to arsenic exacerbates the response to early life influenza infection in mice. Methods: C57BL/6 mice were exposed to arsenic in utero and throughout postnatal life. At 1 week of age, a subgroup of mice were infected with influenza A. We then assessed the acute and long-term effects of arsenic exposure on viral clearance, inflammation, lung structure, and lung function. Results: Early life arsenic exposure reduced the clearance of and exacerbated the inflammatory response to influenza A, and resulted in acute and long-term changes in lung mechanics and airway structure. Conclusions: Increased susceptibility to respiratory infections combined with exaggerated inflammatory responses throughout early life may contribute to the development of bronchiectasis in arsenic-exposed populations. Citation: Ramsey KA, Foong RE, Sly PD, Larcombe AN, Zosky GR. 2013. Early life arsenic exposure and acute and long-term responses to influenza A infection in mice. Environ Health Perspect 121:1187–1193; http://dx.doi.org/10.1289/ehp.1306748 PMID:23968752

  1. Effects of acute exposure to WIFI signals (2.45GHz) on heart variability and blood pressure in Albinos rabbit.

    PubMed

    Saili, Linda; Hanini, Amel; Smirani, Chiraz; Azzouz, Ines; Azzouz, Amina; Sakly, Mohsen; Abdelmelek, Hafedh; Bouslama, Zihad

    2015-09-01

    Electrocardiogram and arterial pressure measurements were studied under acute exposures to WIFI (2.45GHz) during one hour in adult male rabbits. Antennas of WIFI were placed at 25cm at the right side near the heart. Acute exposure of rabbits to WIFI increased heart frequency (+22%) and arterial blood pressure (+14%). Moreover, analysis of ECG revealed that WIFI induced a combined increase of PR and QT intervals. By contrast, the same exposure failed to alter maximum amplitude and P waves. After intravenously injection of dopamine (0.50ml/kg) and epinephrine (0.50ml/kg) under acute exposure to RF we found that, WIFI alter catecholamines (dopamine, epinephrine) action on heart variability and blood pressure compared to control. These results suggest for the first time, as far as we know, that exposure to WIFI affect heart rhythm, blood pressure, and catecholamines efficacy on cardiovascular system; indicating that radiofrequency can act directly and/or indirectly on cardiovascular system. PMID:26356390

  2. Chronic and Acute Exposures to the World Trade Center Disaster and Lower Respiratory Symptoms: Area Residents and Workers

    PubMed Central

    Friedman, Stephen M.; Pillai, Parul S.; Reibman, Joan; Berger, Kenneth I.; Goldring, Roberta; Stellman, Steven D.; Farfel, Mark

    2012-01-01

    Objectives. We assessed associations between new-onset (post–September 11, 2001 [9/11]) lower respiratory symptoms reported on 2 surveys, administered 3 years apart, and acute and chronic 9/11-related exposures among New York City World Trade Center–area residents and workers enrolled in the World Trade Center Health Registry. Methods. World Trade Center–area residents and workers were categorized as case participants or control participants on the basis of lower respiratory symptoms reported in surveys administered 2 to 3 and 5 to 6 years after 9/11. We created composite exposure scales after principal components analyses of detailed exposure histories obtained during face-to-face interviews. We used multivariate logistic regression models to determine associations between lower respiratory symptoms and composite exposure scales. Results. Both acute and chronic exposures to the events of 9/11 were independently associated, often in a dose-dependent manner, with lower respiratory symptoms among individuals who lived and worked in the area of the World Trade Center. Conclusions. Study findings argue for detailed assessments of exposure during and after events in the future from which potentially toxic materials may be released and for rapid interventions to minimize exposures and screen for potential adverse health effects. PMID:22515865

  3. Changes in cholesterol homeostasis and acute phase response link pulmonary exposure to multi-walled carbon nanotubes to risk of cardiovascular disease.

    PubMed

    Poulsen, Sarah S; Saber, Anne T; Mortensen, Alicja; Szarek, Józef; Wu, Dongmei; Williams, Andrew; Andersen, Ole; Jacobsen, Nicklas R; Yauk, Carole L; Wallin, Håkan; Halappanavar, Sabina; Vogel, Ulla

    2015-03-15

    Adverse lung effects following pulmonary exposure to multi-walled carbon nanotubes (MWCNTs) are well documented in rodents. However, systemic effects are less understood. Epidemiological studies have shown increased cardiovascular disease risk after pulmonary exposure to airborne particles, which has led to concerns that inhalation exposure to MWCNTs might pose similar risks. We analyzed parameters related to cardiovascular disease, including plasma acute phase response (APR) proteins and plasma lipids, in female C57BL/6 mice exposed to a single intratracheal instillation of 0, 18, 54 or 162μg/mouse of small, entangled (CNTSmall, 0.8±0.1μm long) or large, thick MWCNTs (CNTLarge, 4±0.4μm long). Liver tissues and plasma were harvested 1, 3 and 28days post-exposure. In addition, global hepatic gene expression, hepatic cholesterol content and liver histology were used to assess hepatic effects. The two MWCNTs induced similar systemic responses despite their different physicochemical properties. APR proteins SAA3 and haptoglobin, plasma total cholesterol and low-density/very low-density lipoprotein were significantly increased following exposure to either MWCNTs. Plasma SAA3 levels correlated strongly with pulmonary Saa3 levels. Analysis of global gene expression revealed perturbation of the same biological processes and pathways in liver, including the HMG-CoA reductase pathway. Both MWCNTs induced similar histological hepatic changes, with a tendency towards greater response following CNTLarge exposure. Overall, we show that pulmonary exposure to two different MWCNTs induces similar systemic and hepatic responses, including changes in plasma APR, lipid composition, hepatic gene expression and liver morphology. The results link pulmonary exposure to MWCNTs with risk of cardiovascular disease. PMID:25620056

  4. No Effects of Acute Exposure to Wi-Fi Electromagnetic Fields on Spontaneous EEG Activity and Psychomotor Vigilance in Healthy Human Volunteers.

    PubMed

    Zentai, Norbert; Csathó, Árpád; Trunk, Attila; Fiocchi, Serena; Parazzini, Marta; Ravazzani, Paolo; Thuróczy, György; Hernádi, István

    2015-12-01

    Mobile equipment use of wireless fidelity (Wi-Fi) signal modulation has increased exponentially in the past few decades. However, there is inconclusive scientific evidence concerning the potential risks associated with the energy deposition in the brain from Wi-Fi and whether Wi-Fi electromagnetism interacts with cognitive function. In this study we investigated possible neurocognitive effects caused by Wi-Fi exposure. First, we constructed a Wi-Fi exposure system from commercial parts. Dosimetry was first assessed by free space radiofrequency field measurements. The experimental exposure system was then modeled based on real geometry and physical characteristics. Specific absorption rate (SAR) calculations were performed using a whole-body, realistic human voxel model with values corresponding to conventional everyday Wi-Fi exposure (peak SAR10g level was 99.22 mW/kg with 1 W output power and 100% duty cycle). Then, in two provocation experiments involving healthy human volunteers we tested for two hypotheses: 1. Whether a 60 min long 2.4 GHz Wi-Fi exposure affects the spectral power of spontaneous awake electroencephalographic (sEEG) activity (N = 25); and 2. Whether similar Wi-Fi exposure modulates the sustained attention measured by reaction time in a computerized psychomotor vigilance test (PVT) (N = 19). EEG data were recorded at midline electrode sites while volunteers watched a silent documentary. In the PVT task, button press reaction time was recorded. No measurable effects of acute Wi-Fi exposure were found on spectral power of sEEG or reaction time in the psychomotor vigilance test. These results indicate that a single, 60 min Wi-Fi exposure does not alter human oscillatory brain function or objective measures of sustained attention. PMID:26600173

  5. Targeting neurotransmitter receptors with nanoparticles in vivo allows single-molecule tracking in acute brain slices

    PubMed Central

    Varela, Juan A.; Dupuis, Julien P.; Etchepare, Laetitia; Espana, Agnès; Cognet, Laurent; Groc, Laurent

    2016-01-01

    Single-molecule imaging has changed the way we understand many biological mechanisms, particularly in neurobiology, by shedding light on intricate molecular events down to the nanoscale. However, current single-molecule studies in neuroscience have been limited to cultured neurons or organotypic slices, leaving as an open question the existence of fast receptor diffusion in intact brain tissue. Here, for the first time, we targeted dopamine receptors in vivo with functionalized quantum dots and were able to perform single-molecule tracking in acute rat brain slices. We propose a novel delocalized and non-inflammatory way of delivering nanoparticles (NPs) in vivo to the brain, which allowed us to label and track genetically engineered surface dopamine receptors in neocortical neurons, revealing inherent behaviour and receptor activity regulations. We thus propose a NP-based platform for single-molecule studies in the living brain, opening new avenues of research in physiological and pathological animal models. PMID:26971573

  6. Targeting neurotransmitter receptors with nanoparticles in vivo allows single-molecule tracking in acute brain slices

    NASA Astrophysics Data System (ADS)

    Varela, Juan A.; Dupuis, Julien P.; Etchepare, Laetitia; Espana, Agnès; Cognet, Laurent; Groc, Laurent

    2016-03-01

    Single-molecule imaging has changed the way we understand many biological mechanisms, particularly in neurobiology, by shedding light on intricate molecular events down to the nanoscale. However, current single-molecule studies in neuroscience have been limited to cultured neurons or organotypic slices, leaving as an open question the existence of fast receptor diffusion in intact brain tissue. Here, for the first time, we targeted dopamine receptors in vivo with functionalized quantum dots and were able to perform single-molecule tracking in acute rat brain slices. We propose a novel delocalized and non-inflammatory way of delivering nanoparticles (NPs) in vivo to the brain, which allowed us to label and track genetically engineered surface dopamine receptors in neocortical neurons, revealing inherent behaviour and receptor activity regulations. We thus propose a NP-based platform for single-molecule studies in the living brain, opening new avenues of research in physiological and pathological animal models.

  7. Persistence of Breakage in Specific Chromosome Bands 6 Years after Acute Exposure to Oil

    PubMed Central

    Francés, Alexandra; Hildur, Kristin; Barberà, Joan Albert; Rodríguez-Trigo, Gema; Zock, Jan-Paul; Giraldo, Jesús; Monyarch, Gemma; Rodriguez-Rodriguez, Emma; de Castro Reis, Fernanda; Souto, Ana; Gómez, Federico P.; Pozo-Rodríguez, Francisco; Templado, Cristina; Fuster, Carme

    2016-01-01

    analyses were performed in 47 exposed individuals. A total of 251 breakpoints in exposed individuals) were identified, showing a non-uniform distribution in the human ideogram. Ten chromosome bands were found to be especially prone to breakage through both statistical methods. By comparing these bands with those observed in certain exposed individuals who had already participated the previous study, it was found in both studies that four bands (2q21, 3q27, 5q31 and 17p11.2) are particularly sensitive to breakage. Additionally, the dysfunction in DNA repair mechanisms was not significantly higher in oil-exposed individuals than in non-exposed individuals. Limitations The sample size and the possibility of some kind of selection bias should be considered. Genotoxic results cannot be extrapolated to the high number of individuals who participated occasionally in clean-up tasks. Conclusion Our findings show the existence of at least four target bands (2q21, 3q27, 5q31 and 17p11.2) with a greater propensity to break over time after an acute exposure to oil. The breaks in these bands, which are commonly involved in hematological cancer, may explain the increase of cancer risk reported in chronically benzene-exposed individuals. In addition, a more efficiency of the DNA repair mechanisms has been detected six years after in fishermen who were highly exposed to the oil spill. To date, only this study, performed by our group on the previous and present genotoxic effects, has analyzed the chromosomal regions affected by breakage after an acute oil exposure. PMID:27479010

  8. Differences in pulmonary biochemical and inflammatory responses of rats and guinea pigs resulting from daytime or nighttime, single and repeated exposure to ozone

    SciTech Connect

    Van Bree, L.; Marra, M.; Rombout, P.J. )

    1992-10-01

    Rats and guinea pigs were exposed to 0.8 mg ozone (O3)/m3 (approximately 0.4 ppm) for 12 hr during the daytime, 12 hr during the nighttime, or continuously to investigate circadian variation in O3-induced pulmonary toxicity during single and repeated O3 exposures. Biomarkers in bronchoalveolar lavage (BAL) fluid and lung tissues were measured as indicators of biochemical and inflammatory responses. Nighttime O3 exposure of rats resulted in larger increases of protein, albumin, and inflammatory cells in BAL fluid compared to those after daytime O3 exposure and this daytime-nighttime difference was statistically significant (p < 0.05). Single daytime or nighttime O3 exposure of guinea pigs resulted in comparable increases of BAL fluid proteins and inflammatory cells without a daytime-nighttime difference. Nighttime and continuous O3 exposure of rats for 3 days resulted in comparable increases in lung antioxidant enzyme activities, both of which differed statistically from effects from daytime O3 exposures (p < 0.05). Continuous O3 exposure of guinea pigs for 3 days caused, in general, statistically larger increases in lung tissue parameters compared to nighttime O3 exposures (p < 0.05). These results suggest that the extent of O3-induced acute pulmonary biochemical and inflammatory responses is directly related to the level of physical and respiratory activity. For rats, effects from continuous O3 exposure appear to be controlled by the nighttime, physically active period. In guinea pigs, the comparable responses following daytime or nighttime O3 exposure seem in accordance with their random behavioral daily activity pattern. This study supports the view that physical activity-related increases in inhaled dose significantly enhance the pulmonary O3 responses.

  9. Acute Radiation Effects Resulting from Exposure to Solar Particle Event-Like Radiation

    NASA Astrophysics Data System (ADS)

    Kennedy, Ann; Cengel, Keith

    2012-07-01

    A major solar particle event (SPE) may place astronauts at significant risk for the acute radiation syndrome (ARS), which may be exacerbated when combined with other space flight stressors, such that the mission or crew health may be compromised. The National Space Biomedical Research Institute (NSBRI) Center of Acute Radiation Research (CARR) is focused on the assessment of risks of adverse biological effects related to the ARS in animal models exposed to space flight stressors combined with the types of radiation expected during an SPE. As part of this program, FDA-approved drugs that may prevent and/or mitigate ARS symptoms are being evaluated. The CARR studies are focused on the adverse biological effects resulting from exposure to the types of radiation, at the appropriate energies, doses and dose-rates, present during an SPE (and standard reference radiations, gamma rays or electrons). The ARS is a phased syndrome which often includes vomiting and fatigue. Other acute adverse biologic effects of concern are the loss of hematopoietic cells, which can result in compromised bone marrow and immune cell functions. There is also concern for skin damage from high SPE radiation doses, including burns, and resulting immune system dysfunction. Using 3 separate animal model systems (ferrets, mice and pigs), the major ARS biologic endpoints being evaluated are: 1) vomiting/retching and fatigue, 2) hematologic changes (with focus on white blood cells) and immune system changes resulting from exposure to SPE radiation with and without reduced weightbearing conditions, and 3) skin injury and related immune system functions. In all of these areas of research, statistically significant adverse health effects have been observed in animals exposed to SPE-like radiation. Countermeasures for the management of ARS symptoms are being evaluated. New research findings from the past grant year will be discussed. Acknowledgements: This research is supported by the NSBRI Center of Acute

  10. Influence of Acute Exposure to High Altitude on Basal and Postprandial Plasma Levels of Gastroenteropancreatic Peptides

    PubMed Central

    Riepl, Rudolf L.; Fischer, Rainald; Hautmann, Hubert; Hartmann, Gunther; Müller, Timo D.; Tschöp, Matthias; Toepfer, Marcell; Otto, Bärbel

    2012-01-01

    Acute mountain sickness (AMS) is characterized by headache often accompanied by gastrointestinal complaints that vary from anorexia through nausea to vomiting. The aim of this study was to investigate the influence of high altitude on plasma levels of gastroenteropancreatic (GEP) peptides and their association to AMS symptoms. Plasma levels of 6 GEP peptides were measured by radioimmunoassay in 11 subjects at 490 m (Munich, Germany) and, after rapid passive ascent to 3454 m (Jungfraujoch, Switzerland), over the course of three days. In a second study (n = 5), the same peptides and ghrelin were measured in subjects who consumed standardized liquid meals at these two elevations. AMS symptoms and oxygen saturation were monitored. In the first study, both fasting (morning 8 a.m.) and stimulated (evening 8 p.m.) plasma levels of pancreatic polypeptide (PP) and cholecystokinin (CCK) were significantly lower at high altitude as compared to baseline, whereas gastrin and motilin concentrations were significantly increased. Fasting plasma neurotensin was significantly enhanced whereas stimulated levels were reduced. Both fasting and stimulated plasma motilin levels correlated with gastrointestinal symptom severity (r = 0.294, p = 0.05, and r = 0.41, p = 0.006, respectively). Mean O2-saturation dropped from 96% to 88% at high altitude. In the second study, meal-stimulated integrated ( = area under curve) plasma CCK, PP, and neurotensin values were significantly suppressed at high altitude, whereas integrated levels of gastrin were increased and integrated VIP and ghrelin levels were unchanged. In summary, our data show that acute exposure to a hypobaric hypoxic environment causes significant changes in fasting and stimulated plasma levels of GEP peptides over consecutive days and after a standardized meal. The changes of peptide levels were not uniform. Based on the inhibition of PP and neurotensin release a reduction of the cholinergic tone can be

  11. Genotoxic evaluation of Mikania laevigata extract on DNA damage caused by acute coal dust exposure.

    PubMed

    Freitas, Tiago P; Heuser, Vanina D; Tavares, Priscila; Leffa, Daniela D; da Silva, Gabriela A; Citadini-Zanette, Vanilde; Romão, Pedro R T; Pinho, Ricardo A; Streck, Emilio L; Andrade, Vanessa M

    2009-06-01

    In the present article, we report data on the possible antigenotoxic activity of Mikania laevigata extract (MLE) after acute intratracheal instillation of coal dust using the comet assay in peripheral blood, bone marrow, and liver cells and the micronucleus test in peripheral blood of Wistar rats. The animals were pretreated for 2 weeks with saline solution (groups 1 and 2) or MLE (100 mg/kg) (groups 3 and 4). On day 15, the animals were anesthetized with ketamine (80 mg/kg) and xylazine (20 mg/kg), and gross mineral coal dust (3 mg/0.3 mL saline) (groups 2 and 4) or saline solution (0.3 mL) (groups 1 and 3) was administered directly in the lung by intratracheal administration. Fifteen days after coal dust or saline instillation, the animals were sacrificed, and the femur, liver, and peripheral blood were removed. The results showed a general increase in the DNA damage values at 8 hours for all treatment groups, probably related to surgical procedures that had stressed the animals. Also, liver cells from rats treated with coal dust, pretreated or not with MLE, showed statistically higher comet assay values compared to the control group at 14 days after exposure. These results could be expected because the liver metabolizes a variety of organic compounds to more polar by-products. On the other hand, the micronucleus assay results did not show significant differences among groups. Therefore, our data do not support the antimutagenic activity of M. laevigata as a modulator of DNA damage after acute coal dust instillation. PMID:19627217

  12. Genotoxic Evaluation of Mikania laevigata Extract on DNA Damage Caused by Acute Coal Dust Exposure

    SciTech Connect

    Freitas, T.P.; Heuser, V.D.; Tavares, P.; Leffa, D.D.; da Silva, G.A.; Citadini-Zanette, V.; Romao, P.R.T.; Pinho, R.A.; Streck, E.L.; Andrade,V.M.

    2009-06-15

    We report data on the possible antigenotoxic activity of Mikania laevigata extract (MLE) after acute intratracheal instillation of coal dust using the comet assay in peripheral blood, bone marrow, and liver cells and the micronucleus test in peripheral blood of Wistar rats. The animals were pretreated for 2 weeks with saline solution (groups 1 and 2) or MLE (100 mg/kg) (groups 3 and 4). On day 15, the animals were anesthetized with ketamine (80 mg/kg) and xylazine (20 mg/kg), and gross mineral coal dust (3 mg/0.3 mL saline) (groups 2 and 4) or saline solution (0.3 mL) (groups 1 and 3) was administered directly in the lung by intratracheal administration. Fifteen days after coal dust or saline instillation, the animals were sacrificed, and the femur, liver, and peripheral blood were removed. The results showed a general increase in the DNA damage values at 8 hours for all treatment groups, probably related to surgical procedures that had stressed the animals. Also, liver cells from rats treated with coal dust, pretreated or not with MLE, showed statistically higher comet assay values compared to the control group at 14 days after exposure. These results could be expected because the liver metabolizes a variety of organic compounds to more polar by-products. On the other hand, the micronucleus assay results did not show significant differences among groups. Therefore, our data do not support the antimutagenic activity of M. laevigata as a modulator of DNA damage after acute coal dust instillation.

  13. Venovenous Extracorporeal Life Support in Single-Ventricle Patients with Acute Respiratory Distress Syndrome

    PubMed Central

    Nair, Alison B.; Oishi, Peter

    2016-01-01

    There is new and growing experience with venovenous extracorporeal life support (VV ECLS) for neonatal and pediatric patients with single-ventricle physiology and acute respiratory distress syndrome (ARDS). Outcomes in this population have been defined but could be improved; survival rates in single-ventricle patients on VV ECLS for respiratory failure are slightly higher than those in single-ventricle patients on venoarterial ECLS for cardiac failure (48 vs. 32–43%), but are lower than in patients with biventricular anatomy (58–74%). To that end, special consideration is necessary for patients with single-ventricle physiology who require VV ECLS for ARDS. Specifically, ARDS disrupts the balance between pulmonary and systemic blood flow through dynamic alterations in cardiopulmonary mechanics. This complexity impacts how to run the VV ECLS circuit and the transition back to conventional support. Furthermore, these patients have a complicated coagulation profile. Both venous and arterial thrombi carry marked risk in single-ventricle patients due to the vulnerability of the pulmonary, coronary, and cerebral circulations. Finally, single-ventricle palliation requires the preservation of low resistance across the pulmonary circulation, unobstructed venous return, and optimal cardiac performance including valve function. As such, the proper timing as well as the particular conduct of ECLS might differ between this population and patients without single-ventricle physiology. The goal of this review is to summarize the current state of knowledge of VV ECLS in the single-ventricle population in the context of these special considerations. PMID:27446889

  14. Changes in cholesterol homeostasis and acute phase response link pulmonary exposure to multi-walled carbon nanotubes to risk of cardiovascular disease

    SciTech Connect

    Poulsen, Sarah S.; Saber, Anne T.; Mortensen, Alicja; Szarek, Józef; Wu, Dongmei; Williams, Andrew; Andersen, Ole; Jacobsen, Nicklas R.; Yauk, Carole L.; Wallin, Håkan; Halappanavar, Sabina; Vogel, Ulla

    2015-03-15

    Adverse lung effects following pulmonary exposure to multi-walled carbon nanotubes (MWCNTs) are well documented in rodents. However, systemic effects are less understood. Epidemiological studies have shown increased cardiovascular disease risk after pulmonary exposure to airborne particles, which has led to concerns that inhalation exposure to MWCNTs might pose similar risks. We analyzed parameters related to cardiovascular disease, including plasma acute phase response (APR) proteins and plasma lipids, in female C57BL/6 mice exposed to a single intratracheal instillation of 0, 18, 54 or 162 μg/mouse of small, entangled (CNT{sub Small}, 0.8 ± 0.1 μm long) or large, thick MWCNTs (CNT{sub Large}, 4 ± 0.4 μm long). Liver tissues and plasma were harvested 1, 3 and 28 days post-exposure. In addition, global hepatic gene expression, hepatic cholesterol content and liver histology were used to assess hepatic effects. The two MWCNTs induced similar systemic responses despite their different physicochemical properties. APR proteins SAA3 and haptoglobin, plasma total cholesterol and low-density/very low-density lipoprotein were significantly increased following exposure to either MWCNTs. Plasma SAA3 levels correlated strongly with pulmonary Saa3 levels. Analysis of global gene expression revealed perturbation of the same biological processes and pathways in liver, including the HMG-CoA reductase pathway. Both MWCNTs induced similar histological hepatic changes, with a tendency towards greater response following CNT{sub Large} exposure. Overall, we show that pulmonary exposure to two different MWCNTs induces similar systemic and hepatic responses, including changes in plasma APR, lipid composition, hepatic gene expression and liver morphology. The results link pulmonary exposure to MWCNTs with risk of cardiovascular disease. - Highlights: • Systemic and hepatic alterations were evaluated in female mice following MWCNT instillation. • Despite being physicochemically

  15. Acute Toxicity Comparison of Single-Walled Carbon Nanotubes in Various Freshwater Organisms

    PubMed Central

    Chung, Young Shin; Kim, Tae Gyu; Kim, Jin Kwon; Lee, Ji Hyun; Lee, Yong Hwa; Kang, Sung Wook

    2015-01-01

    While the commercialization of single-walled carbon nanotubes (SWCNTs) is rapidly expanding, the environmental impact of this nanomaterial is not well understood. Therefore, the present study evaluates the acute aquatic toxicity of SWCNTs towards two freshwater microalgae (Raphidocelis subcapitata and Chlorella vulgaris), a microcrustacean (Daphnia magna), and a fish (Oryzias latipes) based on OECD test guidelines (201, 202, and 203). According to the results, the SWCNTs inhibited the growth of the algae R. subcapitata and C. vulgaris with a median effective concentration (EC50) of 29.99 and 30.96 mg/L, respectively, representing “acute category 3” in the Globally Harmonized System (GHS) of classification and labeling of chemicals. Meanwhile, the acute toxicity test using O. latipes and D. magna did not show any mortality/immobilizing effects up to a concentration of 100.00 mg/L SWCNTs, indicating no hazard category in the GHS classification. In conclusion, SWCNTs were found to induce acute ecotoxicity in freshwater microalgae, yet not in D. magna and medaka fish. PMID:25654094

  16. Acute infantile bilateral striatal necrosis: single-photon emission computed tomography (SPECT) imaging and review.

    PubMed

    Zevit, Noam; Steinmetz, Adam; Kornreich, Liora; Straussberg, Rachel

    2007-10-01

    Acute infantile bilateral striatal necrosis is a rarely described acute neurological syndrome associated with radiological findings. Its etiology and pathogenic mechanisms are unknown. Clinically, the syndrome usually follows respiratory illnesses and presents with an array of neurological findings, including axial ataxia, grimacing, mutism, head nodding, and high-pitched cry. This study follows a child with acute infantile bilateral striatal necrosis both clinically and radiologically. In addition, for the first time, the authors describe the serial findings of single-photon emission computed tomography (SPECT) from onset of illness through 20 months. Their findings indicate an initial insult apparent on both magnetic resonance imaging and SPECT localized to the basal ganglia, which, although improved over time, does not fully regress. The residual lesion on SPECT was clinically associated with only mild attention deficit disorder and no motor pathology. The authors review the published literature concerning acute infantile bilateral striatal necrosis and suggest possible mechanisms of this poorly understood and probably underreported condition. PMID:17940250

  17. Acute toxicity comparison of single-walled carbon nanotubes in various freshwater organisms.

    PubMed

    Sohn, Eun Kyung; Chung, Young Shin; Johari, Seyed Ali; Kim, Tae Gyu; Kim, Jin Kwon; Lee, Ji Hyun; Lee, Yong Hwa; Kang, Sung Wook; Yu, Il Je

    2015-01-01

    While the commercialization of single-walled carbon nanotubes (SWCNTs) is rapidly expanding, the environmental impact of this nanomaterial is not well understood. Therefore, the present study evaluates the acute aquatic toxicity of SWCNTs towards two freshwater microalgae (Raphidocelis subcapitata and Chlorella vulgaris), a microcrustacean (Daphnia magna), and a fish (Oryzias latipes) based on OECD test guidelines (201, 202, and 203). According to the results, the SWCNTs inhibited the growth of the algae R. subcapitata and C. vulgaris with a median effective concentration (EC50) of 29.99 and 30.96 mg/L, respectively, representing "acute category 3" in the Globally Harmonized System (GHS) of classification and labeling of chemicals. Meanwhile, the acute toxicity test using O. latipes and D. magna did not show any mortality/immobilizing effects up to a concentration of 100.00 mg/L SWCNTs, indicating no hazard category in the GHS classification. In conclusion, SWCNTs were found to induce acute ecotoxicity in freshwater microalgae, yet not in D. magna and medaka fish. PMID:25654094

  18. The physiological consequences of varied heat exposure events in adult Myzus persicae: a single prolonged exposure compared to repeated shorter exposures

    PubMed Central

    Andrew, Nigel R.

    2016-01-01

    The study of environmental stress tolerance in aphids has primarily been at low temperatures. In these cases, and in the rare cases of high temperature tolerance assessments, all exposures had been during a single stress event. In the present study, we examined the physiological consequences of repeated high temperature exposure with recovery periods between these stress events in Myzus persicae. We subjected individuals to either a single prolonged three hour heating event, or three one hour heating events with a recovery time of 24 h between bouts. Aphids exposed to repeated bouts of high temperatures had more glucose and higher expression of proteins and osmolyte compounds, such as glycerol, compared to the prolonged exposure group. However, aphids exposed to the repeated high temperature treatment had reduced sources of energy such as trehalose and triglyceride compounds than the prolonged exposure group. Recovery time had more physiological costs (based on production of more protein and consumption of more trehalose and triglyceride) and benefits (based on production of more osmolytes) in repeated high temperature treatments. As aphids are known to respond differently to constant versus ‘natural’ fluctuating temperature regimes, conclusions drawn from constant temperature data sets may be problematic. We suggest future experiments assessing insect responses to thermal stress incorporate a repeated stress and recovery pattern into their methodologies. PMID:27547583

  19. The physiological consequences of varied heat exposure events in adult Myzus persicae: a single prolonged exposure compared to repeated shorter exposures.

    PubMed

    Ghaedi, Behnaz; Andrew, Nigel R

    2016-01-01

    The study of environmental stress tolerance in aphids has primarily been at low temperatures. In these cases, and in the rare cases of high temperature tolerance assessments, all exposures had been during a single stress event. In the present study, we examined the physiological consequences of repeated high temperature exposure with recovery periods between these stress events in Myzus persicae. We subjected individuals to either a single prolonged three hour heating event, or three one hour heating events with a recovery time of 24 h between bouts. Aphids exposed to repeated bouts of high temperatures had more glucose and higher expression of proteins and osmolyte compounds, such as glycerol, compared to the prolonged exposure group. However, aphids exposed to the repeated high temperature treatment had reduced sources of energy such as trehalose and triglyceride compounds than the prolonged exposure group. Recovery time had more physiological costs (based on production of more protein and consumption of more trehalose and triglyceride) and benefits (based on production of more osmolytes) in repeated high temperature treatments. As aphids are known to respond differently to constant versus 'natural' fluctuating temperature regimes, conclusions drawn from constant temperature data sets may be problematic. We suggest future experiments assessing insect responses to thermal stress incorporate a repeated stress and recovery pattern into their methodologies. PMID:27547583

  20. Acute exposure to methamphetamine alters TLR9-mediated cytokine expression in human macrophage.

    PubMed

    Burns, Ariel; Ciborowski, Pawel

    2016-02-01

    Recent studies show that methamphetamine (Meth) use leads to higher susceptibility to and progression of infections, which suggests impairment of the immune system. The first line of defense against infections is the innate immune system and the macrophage is a key player in preventing and fighting infections. So we profiled cytokines over time in Meth treated THP-1 cells, as a human macrophage model, at a relevant concentration using high throughput screening to find a signaling target. We showed that after a single exposure, the effect of Meth on macrophage cytokine production was rapid and time dependent and shifted the balance of expression of cytokines to pro-inflammatory. Our results were analogous to previous reports in that Meth up-regulates TNF-α and IL-8 after two hours of exposure. However, global screening led to the novel identification of CXCL16, CXCL1 and many other up-regulated cytokines. We also showed CCL7 as the most down-regulated chemokine due to Meth exposure, which led us to hypothesize that Meth dysregulates the MyD88-dependent Toll-like receptor 9 (TLR9) signaling pathway. In conclusion, altered cytokine expression in macrophages suggests it could lead to a suppressed innate immunity in people who use Meth. PMID:26387832

  1. Effects of acute chlorpyrifos exposure on in vivo acetylcholine accumulation in rat striatum

    SciTech Connect

    Karanth, Subramanya; Liu, Jing; Mirajkar, Nikita; Pope, Carey . E-mail: carey.pope@okstate.edu

    2006-10-01

    This study examined the acute effects of chlorpyrifos (CPF) on cholinesterase inhibition and acetylcholine levels in the striatum of freely moving rats using in vivo microdialysis. Adult, male Sprague-Dawley rats were treated with vehicle (peanut oil, 2 ml/kg) or CPF (84, 156 or 279 mg/kg, sc) and functional signs of toxicity, body weight and motor activity recorded. Microdialysis was conducted at 1, 4 and 7 days after CPF exposure for measurement of acetylcholine levels in striatum. Rats were then sacrificed and the contralateral striatum and diaphragm were collected for biochemical measurements. Few overt signs of cholinergic toxicity were noted in any rats. Body weight gain was significantly affected in the high-dose (279 mg/kg) group only, while motor activity (nocturnal rearing) was significantly reduced in all CPF-treated groups at one day (84 mg/kg) or from 1-4 days (156 and 279 mg/kg) after dosing. Cholinesterase activities in both diaphragm and striatum were markedly inhibited (50-92%) in a time-dependent manner, but there were relatively minimal dose-related changes. In contrast, time- and dose-dependent changes in striatal acetylcholine levels were noted, with significantly higher levels noted in the high-dose group compared to other groups. Maximal increases in striatal acetylcholine levels were observed at 4-7 days after dosing (84 mg/kg, 7-9-fold; 156 mg/kg, 10-13-fold; 279 mg/kg, 35-57-fold). Substantially higher acetylcholine levels were noted when an exogenous cholinesterase inhibitor was included in the perfusion buffer, but CPF treatment-related differences were substantially lower in magnitude under those conditions. The results suggest that marked differences in acetylcholine accumulation can occur with dosages of CPF eliciting relatively similar degrees of cholinesterase inhibition. Furthermore, the minimal expression of classic signs of cholinergic toxicity in the presence of extensive brain acetylcholine accumulation suggests that some

  2. The effects of acetazolamide and spironolactone on the body water distribution of rabbits during acute exposure to simulated altitude

    NASA Astrophysics Data System (ADS)

    Jain, S. C.; Singh, M. V.; Rawal, S. B.

    1984-06-01

    The role of body water metabolism on acute altitude exposure was studied. The studies were carried out in rabbits divided into four groups, namely, (i) control, (ii) exposed to acute hypoxia, (iii) exposed to acute hypoxia after treatment with 250 mg acetazolamide and (iv) exposed to acute hypoxia after treatment with 25 mg spironolactone. Total body water, extracellular water, intracellular water and blood volume decreased by an insignificant amount on exposure to hypoxia and plasma volume decreased by 5.7% (P<0.025). Treatment with either acetazolamide or spironolactone resulted in further marginal decrease in total body water. In the case of acetazolamide, the loss occurs from both intracellular and extracellular compartments, while treatment with spironolactone resulted in significant loss only from extracellular compartment. Treatment with both the drugs resulted in a small rise in pO2 and pCO2 with a slight decrease in pH. Our data suggested spironolactone to be a better prophylactic agent for use on acute high altitude induction.

  3. Impact of acute exposure to WTC dust on ciliated and goblet cells in lungs of rats

    PubMed Central

    Cohen, Mitchell D.; Vaughan, Joshua M.; Garrett, Brittany; Prophete, Colette; Horton, Lori; Sisco, Maureen; Ghio, Andrew; Zelikoff, Judith; Lung-chi, Chen

    2015-01-01

    Clinical studies and the World Trade Center (WTC) Health Registry have revealed increases in the incidence of chronic (non-cancer) lung disorders among first responders (FR) who were at Ground Zero during the initial 72 h after the collapse. Our previous analyses of rats exposed to building-derived WTC dusts using exposure scenarios/levels that mimicked FR mouth-breathing showed that a single WTC dust exposure led to changes in expression of genes whose products could be involved in the lung ailments, but few other significant pathologies. We concluded that rather than acting as direct inducers of many of the FR health effects, it was more likely inhaled WTC dusts instead may have impacted on toxicities induced by other rescue-related co-pollutants present in Ground Zero air. To allow for such effects to occur, we hypothesized that the alkaline WTC dusts induced damage to the normal ability of the lungs to clear inhaled particles. To validate this, rats were exposed on two consecutive days (2 h/d, by intratracheal inhalation) to WTC dust (collected 12–13 September 2001) and examined over a 1-yr period thereafter for changes in the presence of ciliated cells in the airways and hyperplastic goblet cells in the lungs. WTC dust levels in the lungs were assessed in parallel to verify that any changes in levels of these cells corresponded with decreases in host ability to clear the particles themselves. Image analyses of the rat lungs revealed a significant decrease in ciliated cells and increase in hyperplastic goblet cells due to the single series of WTC dust exposures. The study also showed there was only a nominal non-significant decrease (6–11%) in WTC dust burden over a 1-yr period after the final exposure. These results provide support for our current hypothesis that exposure to WTC dusts caused changes in airway morphology/cell composition; such changes could, in turn, have led to potential alterations in the clearance/toxicities of other pollutants inhaled

  4. Impact of acute exposure to WTC dust on ciliated and goblet cells in lungs of rats.

    PubMed

    Cohen, Mitchell D; Vaughan, Joshua M; Garrett, Brittany; Prophete, Colette; Horton, Lori; Sisco, Maureen; Ghio, Andrew; Zelikoff, Judith; Lung-chi, Chen

    2015-01-01

    Clinical studies and the World Trade Center (WTC) Health Registry have revealed increases in the incidence of chronic (non-cancer) lung disorders among first responders (FR) who were at Ground Zero during the initial 72 h after the collapse. Our previous analyses of rats exposed to building-derived WTC dusts using exposure scenarios/levels that mimicked FR mouth-breathing showed that a single WTC dust exposure led to changes in expression of genes whose products could be involved in the lung ailments, but few other significant pathologies. We concluded that rather than acting as direct inducers of many of the FR health effects, it was more likely inhaled WTC dusts instead may have impacted on toxicities induced by other rescue-related co-pollutants present in Ground Zero air. To allow for such effects to occur, we hypothesized that the alkaline WTC dusts induced damage to the normal ability of the lungs to clear inhaled particles. To validate this, rats were exposed on two consecutive days (2 h/d, by intratracheal inhalation) to WTC dust (collected 12-13 September 2001) and examined over a 1-yr period thereafter for changes in the presence of ciliated cells in the airways and hyperplastic goblet cells in the lungs. WTC dust levels in the lungs were assessed in parallel to verify that any changes in levels of these cells corresponded with decreases in host ability to clear the particles themselves. Image analyses of the rat lungs revealed a significant decrease in ciliated cells and increase in hyperplastic goblet cells due to the single series of WTC dust exposures. The study also showed there was only a nominal non-significant decrease (6-11%) in WTC dust burden over a 1-yr period after the final exposure. These results provide support for our current hypothesis that exposure to WTC dusts caused changes in airway morphology/cell composition; such changes could, in turn, have led to potential alterations in the clearance/toxicities of other pollutants inhaled

  5. A single exposure to acrolein causes arrhythmogenesis, cardiac electrical dysfunction and decreased heart rate variability in hypertensive rats

    EPA Science Inventory

    Epidemiological studies demonstrate an association between cardiovascular morbidity, arrhythmias, and exposure to air toxicants such as acrolein. We hypothesized that a single exposure to acrolein would increase arrhythmias and cause changes in the electrocardiogram (ECG) of hype...

  6. Probabilistic assessment of the cumulative dietary acute exposure of the population of Denmark to organophosphorus and carbamate pesticides.

    PubMed

    Jensen, B H; Petersen, A; Christensen, T

    2009-07-01

    Organophosphorus and carbamate pesticides are acetylcholinesterase-inhibiting pesticides and as such have a common mode of action. We assessed the cumulative acute exposure of the population of Denmark to 25 organophosphorus and carbamate pesticide residues from the consumption of fruit, vegetables and cereals. The probabilistic approach was used in the assessments. Residue data obtained from the Danish monitoring programme carried out in the period 2004-2007, which included 6704 samples of fruit, vegetables and cereals, were used in the calculations. Food consumption data were obtained from the nationwide dietary survey conducted in 2000-2002. Contributions from 43 commodities were included in the calculations. We used the relative potency factor (RPF) approach to normalize the toxicity of the various organophosphorus and carbamate pesticides to the two index compounds chlorpyriphos and methamidophos. RPF values derived from the literature were used in the calculations. We calculated the cumulative acute exposure to 1.8% and 0.8% of the acute reference dose (ARfD) of 100 microg kg(-1) body weight (bw) day(-1) of chlorpyrifos as an index compound at the 99.9th percentile (P99.5) for children and adults, respectively. When we used methamidophos as the index compound, the cumulative acute intakes were calculated to 31.3% and 13.8% of the ARfD of 3 microg kg(-1) bw day(-1) at P99.9 for children and adults, respectively. With both index compounds, the greatest contributor to the cumulative acute exposure was apple. The results show that there is no cumulative acute risk for Danish consumers to acetylcholinesterase-inhibiting pesticides. PMID:19680979

  7. Isolated single coronary artery presenting as acute coronary syndrome: case report and review.

    PubMed

    Mahapatro, Anil K; Patro, A Sarat K; Sujatha, Vipperala; Sinha, Sudhir C

    2014-06-01

    Congenital single coronary artery is commonly associated with complex congenital heart diseases and manifests in infancy or childhood. But isolated single coronary artery is a rare congenital anomaly which can present as acute coronary syndrome in adults. The aim of the work is to discuss on isolated single coronary artery in two adults presenting as acute coronary syndrome. The first case underwent coronary angiography (CAG) through right radial route, but switched over to femoral for confirmation of diagnosis and due to radial spasm. An aortic root angiogram was done to rule out presence of any other coronary ostia. It revealed a single coronary artery originating from right sinus of valsalva. After giving rise to posterior descending artery branch at crux, it continued in the atrioventricular groove to the anterior basal surface of the heart and traversed as anterior descending artery. There was no atheromatous occlusive stenosis. This is R-I type single coronary artery as per Lipton classification. In the second case, angiography was completed through right radial route. It revealed a single coronary artery arising from right aortic sinus. Anterior descending and circumflex branch were originating from proximal common trunk of the single coronary artery and supplying the left side of the heart. The right coronary artery has diffuse atheromatous disease without significant stenosis in any major branch. This is R-III C type as per Lipton classification. A coronary anomaly of both origin and course is very rare. It may be encountered in adults evaluated for atherosclerotic coronary heart disease. Knowledge and understanding of anatomical types of this congenital anomaly will reduce time, anxiety, complications during CAG and cardiac surgery. PMID:25075168

  8. Acute exposure to 17α-ethinylestradiol disrupts audience effect on male-female interactions in Betta splendens.

    PubMed

    Forette, Lindsay M; Mannion, Krystal L; Dzieweczynski, Teresa L

    2015-04-01

    Endocrine disrupting chemicals can negatively impact the morphology and behavior of organisms inhabiting polluted waters. Male-typical behaviors are often reduced after exposure, suggesting that exposure may have population-level effects. One way in which exposure may exert population-level effects is by interfering with communication within a network of individuals. Acute exposure to the estrogen mimic 17α-ethinylestradiol (EE2) disrupts the ability of male Siamese fighting fish, Betta splendens, to modify their behavior during male-male interactions when an audience is present. However, it is unknown whether audience effects during male-female interactions may be similarly altered. To examine this, male-female pairs that were given an acute exposure to EE2 or remained unexposed interacted in the presence of a female, male, or no audience. Sex differences were found between unexposed males and females. More interactant-directed gill flaring was displayed by control males when a male audience was present while control females performed this behavior more in the presence of an audience, regardless of sex. Both males and females in the control group performed more interactant-directed tail beats in the presence of a female audience. EE2 exposure made all audience effects disappear as treated males and females did not differ in their responses between audience types. These results demonstrate that acute exposure to EE2 may disrupt behavioral adjustments to audience type within a social network. This disruption may, in turn, influence population dynamics in this species as both males and females use information obtained from observing interactions in later encounters with the observed individuals. PMID:25697944

  9. Antenatal Magnesium Sulfate Exposure and Acute Cardiorespiratory Events in Preterm Infants

    PubMed Central

    DE JESUS, Lilia C.; SOOD, Beena G.; SHANKARAN, Seetha; KENDRICK, Mr. Douglas; DAS, Abhik; BELL, Edward F.; STOLL, Barbara J.; LAPTOOK, Abbot R.; WALSH, Michele C.; CARLO, Waldemar A.; SANCHEZ, Pablo J.; VAN MEURS, Krisa P.; BARA, Ms. Rebecca; HALE, Ellen C.; NEWMAN, Ms. Nancy S.; BALL, Ms. M. Bethany; HIGGINS, Rosemary D.

    2014-01-01

    Objective Antenatal magnesium (anteMg) is used for tocolysis, pregnancy-induced hypertension (PIH) and neuroprotection for preterm birth. Infants exposed to anteMg are at risk for respiratory depression and resuscitation in the delivery room (DR). The study objective was to compare the risk of acute cardio-respiratory (CR) events among preterm infants exposed to anteMg and those unexposed (noMg). Study Design This was a retrospective analysis of prospective data collected in the NICHD Neonatal Research Network's Generic Database from 4/1/11 to 3/31/12. The primary outcome was DR intubation or mechanical ventilation (MV) at birth or on day 1 of life. Secondary outcomes were endotracheal MV (eMV), hypotension and other neonatal morbidities and mortality. Logistic regression analysis evaluated the risk of primary outcomes after adjustment for gestational age (GA), center, antenatal steroids (ANS) and PIH/eclampsia. Results We evaluated 1,544 infants <29 weeks GA (1,091 in anteMg group and 453 in noMg group). Mothers in the anteMg group were more likely to have higher education, PIH/eclampsia and ANS; while their infants were younger in gestation and weighed less (P<0.05). The primary outcome, mortality and neonatal morbidities were similar between groups; while eMV and hypotension were significantly less among the anteMg group compared to the noMg group. AnteMg exposure was significantly associated with decreased risk of hypotension on day 1 of life and eMV on day 3 of life in the regression analysis. Conclusion Preterm infants <29 weeks GA who were exposed to anteMg did not suffer worse CR outcomes compared to those without exposure. PMID:25046806

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

    PubMed

    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 < 0.05) except in the group treated with 1.00 mg L(-1) Zn (P < 0.05), where the increase of OCR was observed. The OCRs in groups chronically exposed to metals were significantly lower than that in the control group (P < 0.05). The activity of both pyruvate kinase (PK) and hexokinase (HK) in sea cucumbers followed: respiratory tree > 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

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

    PubMed Central

    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 < 0.05) except in the group treated with 1.00 mg L−1 Zn (P < 0.05), where the increase of OCR was observed. The OCRs in groups chronically exposed to metals were significantly lower than that in the control group (P < 0.05). The activity of both pyruvate kinase (PK) and hexokinase (HK) in sea cucumbers followed: respiratory tree > 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

  12. Acute 7,12-dimethylbenz[a]anthracene exposure causes differential concentration-dependent follicle depletion and gene expression in neonatal rat ovaries

    PubMed Central

    Madden, Jill A.; Hoyer, Patricia B.; Devine, Patrick J.; Keating, Aileen F.

    2014-01-01

    Chronic exposure to the polycyclic aromatic hydrocarbon 7,12-dimethylbenz[a]anthracene (DMBA), generated during combustion of organic matter including cigarette smoke, depletes all ovarian follicle types in the mouse and rat, and in vitro models mimic this effect. To investigate the mechanisms involved in follicular depletion during acute DMBA exposure, two concentrations of DMBA at which follicle depletion has (75 nM) and has not (12.5 nM) been observed were investigated. Postnatal day four F344 rat ovaries were maintained in culture for four days before a single exposure to vehicle control (1% DMSO; CT) or DMBA (12 nM; low-concentration or 75 nM; high-concentration). After four or eight additional days of culture, DMBA-induced follicle depletion was evaluated via follicle enumeration. Relative to control, DMBA did not affect follicle numbers after 4 days of exposure, but induced large primary follicle loss at both concentrations after 8 days; while, the low-concentration DMBA also caused secondary follicle depletion. Neither concentration affected primordial or small primary follicle number. RNA was isolated and quantitative RT-PCR performed prior to follicle loss to measure mRNA levels of genes involved in xenobiotic metabolism (Cyp2e1, Gstmu, Gstpi, Ephx1), autophagy (Atg7, Becn1), oxidative stress response (Sod1, Sod2) and the phosphatidylinositol 3-kinase (PI3K) pathway (Kitlg, cKit, Akt1) 1, 2 and 4 days after exposure. With the exception of Atg7 and cKit, DMBA increased (P < 0.05) expression of all genes investigated. Also, BECN1 and pAKTThr308 protein levels were increased while cKIT was decreased by DMBA exposure. Taken together, these results suggest an increase in DMBA bioactivation, add to the mechanistic understanding of DMBA-induced ovotoxicity and raise concern regarding female low concentration DMBA exposures. PMID:24576726

  13. Acute, whole-body microwave exposure and testicular function of rats

    SciTech Connect

    Lebovitz, R.M.; Johnson, L.

    1987-01-01

    Male Sprague-Dawley rats were exposed for 8 h to continuous-wave microwave radiation (MWR, 1.3 Ghz) at a mean specific absorbed dose rate of 9 mW/g. MWR exposure and sham-irradiation took place in unidirectionally energized cylindrical waveguide sections, within which the animals were essentially unrestrained. The MWR treatment in this setting was determined to yield an elevation of deep rectal temperature to 4.5 degrees C. The animals were taken for analysis at 6.5, 13, 26, and 52 days following treatment, which corresponded to .5, 1, 2, and 4 cycles of the seminiferous epithelium. Net mass of testes, epididymides, and seminal vesicles; daily sperm production (DSP) per testis and per gram of testis; and the number of epididymal sperm were determined. The levels of circulating follicle-stimulating hormone (FSH) and leutinizing hormone (LH) were derived via radioimmunoassay of plasma samples taken at the time of sacrifice. Despite the evident acute thermogenesis of the MWR at 9 mW/g, no substantial decrement in testicular function was found. We conclude that, in the unrestrained rat, whole body irradiation at 9 mW/g, while sufficient to induce evident hyperthermia, is not a sufficient condition for disruption of any of these key measures of testicular function.

  14. Study of physiological responses to acute carbon monoxide exposure with a human patient simulator.

    PubMed

    Cesari, Whitney A; Caruso, Dominique M; Zyka, Enela L; Schroff, Stuart T; Evans, Charles H; Hyatt, Jon-Philippe K

    2006-12-01

    Human patient simulators are widely used to train health professionals and students in a clinical setting, but they also can be used to enhance physiology education in a laboratory setting. Our course incorporates the human patient simulator for experiential learning in which undergraduate university juniors and seniors are instructed to design, conduct, and present (orally and in written form) their project testing physiological adaptation to an extreme environment. This article is a student report on the physiological response to acute carbon monoxide exposure in a simulated healthy adult male and a coal miner and represents how 1) human patient simulators can be used in a nonclinical way for experiential hypothesis testing; 2) students can transition from traditional textbook learning to practical application of their knowledge; and 3) student-initiated group investigation drives critical thought. While the course instructors remain available for consultation throughout the project, the relatively unstructured framework of the assignment drives the students to create an experiment independently, troubleshoot problems, and interpret the results. The only stipulation of the project is that the students must generate an experiment that is physiologically realistic and that requires them to search out and incorporate appropriate data from primary scientific literature. In this context, the human patient simulator is a viable educational tool for teaching integrative physiology in a laboratory environment by bridging textual information with experiential investigation. PMID:17108253

  15. Therapist-Aided Exposure for Women with Lifelong Vaginismus: A Replicated Single-Case Design

    ERIC Educational Resources Information Center

    ter Kuile, Moniek M.; Bulte, Isis; Weijenborg, Philomeen T. M.; Beekman, Aart; Melles, Reinhilde; Onghena, Patrick

    2009-01-01

    Vaginismus is commonly described as a persistent difficulty in allowing vaginal entry of a penis or other object. Lifelong vaginismus occurs when a woman has never been able to have intercourse. A replicated single-case A-B-phase design was used to investigate the effectiveness of therapist-aided exposure for lifelong vaginismus. A baseline period…

  16. A single exposure to photochemical smog causes airway irritation and cardiac dysrhythmia in mice

    EPA Science Inventory

    The data presented here shows that a single exposure to photochemical smog causes airway irritation and cardiac dysrhythmia in mice. Smog, which is a complex mixture of particulate matter and gaseous irritants (ozone, sulfur dioxide, reactive aldehydes), as well as components whi...

  17. Development of short, acute exposure hazard estimates: a tool for assessing the effects of chemical spills in aquatic environments.

    PubMed

    Bejarano, Adriana C; Farr, James K

    2013-08-01

    Management decisions aimed at protecting aquatic resources following accidental chemical spills into rivers and coastal estuaries require estimates of toxic thresholds derived from realistic spill conditions: acute pulse exposures of short duration (h), information which often is unavailable. Most existing toxicity data (median lethal concentration or median effective concentration) come from tests performed under constant exposure concentrations and exposure durations in the 24-h to 96-h range, conditions not typical of most chemical spills. Short-exposure hazard concentration estimates were derived for selected chemicals using empirical toxicity data. Chemical-specific 5th percentile hazard concentrations (HC5) of species sensitivity distributions (SSD) from individual exposure durations (6-96 h) were derived via bootstrap resampling and were plotted against their original exposure durations to estimate HC5s and 95% confidence intervals (CIs) at shorter exposures (1, 2, and 4 h). This approach allowed the development of short-exposure HC5s for 12 chemicals. Model verification showed agreement between observed and estimated short-exposure HC5s (r(2) adjusted = 0.95, p < 0.0001), and comparison of estimated short-exposure HC5s with empirical toxicity data indicated generally conservative hazard estimates. This approach, applied to 2 real spill incidents, indicated hazard estimates above expected environmental concentrations (acrylonitrile), and suggested that environmental concentrations likely exceeded short-exposure hazard estimates (furfural). Although estimates generated through this approach were likely overprotective, these were derived from environmentally realistic exposure durations, providing risk-assessors with a tool to manage field decisions. Environ Toxicol Chem 2013;32:1918-1927. © 2013 SETAC. PMID:23625642

  18. Effect of acute cold exposure and insulin hypoglycemia on plasma thyrotropin levels by IRMA in healthy young males.

    PubMed

    Vigas, M; Martino, E; Bukovská, M; Langer, P

    1988-12-01

    Thyrotropin (TSH) levels in plasma were estimated with the aid of immunoradiometric assay in two groups of healthy male subjects aged 21-22 years in two experiments: 1. acute (30 min) exposure to 4 degrees C in a cold room; 2. insulin (0.01 U per kg i.v.) hypoglycemia at room temperature and at 55 degrees C. Immediately after cold exposure a decrease of TSH level was found (P less than 0.01), while no changes were observed during 30 min exposure. After insulin injection a significant decrease (P less than 0.05 to less than 0.001) of TSH level was found at 45 to 120 min irrespectively of the ambient temperature. In addition, increased levels of noradrenaline and decreased levels of growth hormone after cold exposure are presented. PMID:3243203

  19. Acute chlorine gas exposure produces transient inflammation and a progressive alteration in surfactant composition with accompanying mechanical dysfunction.

    PubMed

    Massa, Christopher B; Scott, Pamela; Abramova, Elena; Gardner, Carol; Laskin, Debra L; Gow, Andrew J

    2014-07-01

    Acute Cl2 exposure following industrial accidents or military/terrorist activity causes pulmonary injury and severe acute respiratory distress. Prior studies suggest that antioxidant depletion is important in producing dysfunction, however a pathophysiologic mechanism has not been elucidated. We propose that acute Cl2 inhalation leads to oxidative modification of lung lining fluid, producing surfactant inactivation, inflammation and mechanical respiratory dysfunction at the organ level. C57BL/6J mice underwent whole-body exposure to an effective 60ppm-hour Cl2 dose, and were euthanized 3, 24 and 48h later. Whereas pulmonary architecture and endothelial barrier function were preserved, transient neutrophilia, peaking at 24h, was noted. Increased expression of ARG1, CCL2, RETLNA, IL-1b, and PTGS2 genes was observed in bronchoalveolar lavage (BAL) cells with peak change in all genes at 24h. Cl2 exposure had no effect on NOS2 mRNA or iNOS protein expression, nor on BAL NO3(-) or NO2(-). Expression of the alternative macrophage activation markers, Relm-α and mannose receptor was increased in alveolar macrophages and pulmonary epithelium. Capillary surfactometry demonstrated impaired surfactant function, and altered BAL phospholipid and surfactant protein content following exposure. Organ level respiratory function was assessed by forced oscillation technique at 5 end expiratory pressures. Cl2 exposure had no significant effect on either airway or tissue resistance. Pulmonary elastance was elevated with time following exposure and demonstrated PEEP refractory derecruitment at 48h, despite waning inflammation. These data support a role for surfactant inactivation as a physiologic mechanism underlying respiratory dysfunction following Cl2 inhalation. PMID:24582687

  20. Acute Chlorine Gas Exposure Produces Transient Inflammation and a Progressive Alteration in Surfactant Composition with Accompanying Mechanical Dysfunction

    PubMed Central

    Massa, Christopher B; Scott, Pamela; Abramova, Elena; Gardner, Carol; Laskin, Debra L; Gow, Andrew J

    2014-01-01

    Acute Cl2 exposure following industrial accidents or military/terrorist activity causes pulmonary injury and severe acute respiratory distress. Prior studies suggest that antioxidant depletion is important in producing dysfunction, however a pathophysiologic mechanism has not been elucidated. We propose that acute Cl2 inhalation leads to oxidative modification of lung lining fluid, producing surfactant inactivation, inflammation and mechanical respiratory dysfunction at the organ level. C57BL/6J mice underwent whole-body exposure to an effective 60 ppm-hour Cl2 dose, and were sacrificed 3, 24 and 48 hours later. Whereas pulmonary architecture and endothelial barrier function were preserved, transient neutrophilia, peaking at 24 hours, was noted. Increased expression of ARG1, CCL2, RETLNA, IL-1b, and PTGS2 genes was observed in bronchoalveolar lavage (BAL) cells with peak change in all genes at 24 hours. Cl2 exposure had no effect on NOS2 mRNA or iNOS protein expression, nor on BAL NO3− or NO2−. Expression of the alternative macrophage activation markers, Relm-α and mannose receptor was increased in alveolar macrophages and pulmonary epithelium. Capillary surfactometry demonstrated impaired surfactant function, and altered BAL phospholipid and surfactant protein content following exposure. Organ level respiratory function was assessed by forced oscillation technique at 5 end expiratory pressures. Cl2 exposure had no significant effect on either airway or tissue resistance. Pulmonary elastance was elevated with time following exposure and demonstrated PEEP refractory derecruitment at 48 hours, despite waning inflammation. These data support a role for surfactant inactivation as a physiologic mechanism underlying respiratory dysfunction following Cl2 inhalation. PMID:24582687

  1. Development of acute lung injury after the combination of intravenous bleomycin and exposure to hyperoxia in rats.

    PubMed Central

    Hay, J G; Haslam, P L; Dewar, A; Addis, B; Turner-Warwick, M; Laurent, G J

    1987-01-01

    Pulmonary toxicity is an important adverse effect of bleomycin treatment. Very little is known of the mechanisms underlying the development of lung injury, especially after intravenous administration, or how it can be modulated. In this study acute lung injury induced by bleomycin has been examined in rats by assessment of alveolar lavage cell profiles, histological examination, and measurement of the total pulmonary extravascular albumin space. Intratracheal instillation of bleomycin 1.5 mg resulted in a severe pneumonitis with influx of inflammatory cells into the alveoli as assessed by alveolar lavage, oedema of the alveolar walls, and up to an eight fold increase in the total pulmonary extravascular albumin space, maximal at 72 hours. Intravenous bleomycin 0.15-5 mg produced no detectable injury when assessed in these ways. Exposure to hyperoxia (40-90%) after intravenous bleomycin, however, induced lung injury similar to that produced by intratracheal bleomycin. A much more severe injury followed administration of intravenous bleomycin after an exposure to hyperoxia, which itself resulted in lung injury; but lung injury was still detectable after bleomycin when the exposure to hyperoxia was insufficient to induce changes in control animals. Lung injury was not observed when the exposure to hyperoxia preceded bleomycin treatment. These results indicate the importance of oxygen in the pathways leading to acute lung injury following intravenous bleomycin. We conclude that exposure to oxygen might induce lung injury during and after bleomycin treatment, and suggest that in these circumstances oxygen therapy should be kept to a minimum. PMID:2443992

  2. Hospital Performance Indicators and Their Associated Factors in Acute Child Poisoning at a Single Poison Center, Central Saudi Arabia.

    PubMed

    Alanazi, Menyfah Q; Al-Jeriasy, Majed I; Al-Assiri, Mohammed H; Afesh, Lara Y; Alhammad, Fahad; Salam, Mahmoud

    2015-12-01

    Admission rate and length of stay (LOS) are two hospital performance indicators that affect the quality of care, patients' satisfaction, bed turnover, and health cost expenditures. The aim of the study was to identify factors associated with higher admission rates and extended average LOS among acutely poisoned children at a single poison center, central Saudi Arabia.This is a cross-sectional, poison and medical chart review between 2009 and 2011. Exposures were child characteristics, that is, gender, age, body mass index (BMI), health history, and Canadian 5-level triage scale. Poison incident characteristics were, that is, type, exposure route, amount, form, home remedy, and arrival time to center. Admission status and LOS were obtained from records. Chronic poisoning, plant allergies, and venomous bites were excluded. Bivariate and regression analyses were applied. Significance at P < 0.05.Of the 315 eligible cases, (72%) were toddlers with equal gender distribution, (58%) had normal BMI, and (77%) were previously healthy. Poison substances were pharmaceutical drugs (63%) versus chemical products (37%). Main exposure route was oral (98%). Home remedy was observed in (21.9%), which were fluids, solutes, and/or gag-induced vomiting. Almost (52%) arrived to center >1 h. Triage levels: non-urgent cases (58%), less urgent (11%), urgent (18%), emergency (12%), resuscitative (1%). Admission rate was (20.6%) whereas av. LOS was 13 ± 22 h. After adjusting and controlling for confounders, older children (adj.OR = 1.19) and more critical triage levels (adj.OR = 1.35) were significantly associated with higher admission rates compared to younger children and less critical triage levels (adj.P = 0.006) and (adj.P = 0.042) respectively. Home remedy prior arrival was significantly associated with higher av. LOS (Beta = 9.48, t = 2.99), compared to those who directly visited the center, adj.P = 0.003.Hospital administrators are cautioned

  3. Acute and chronic exposure to ethanol and the electrophysiology of the brush border membrane of rat small intestine.

    PubMed Central

    al-Balool, F; Debnam, E S; Mazzanti, R

    1989-01-01

    In this study we have investigated the effects of (a) chronic ethanol intake on glucose and galactose absorption across the rat jejunum in vivo and on the potential difference across the isolated brush border membrane (Vm) and (b) acute exposure to ethanol (4% or 8%) and acetaldehyde (0.25%) on changes in Vm associated with Na(+)-dependent galactose absorption across the jejunum and ileum. Chronic ethanol intake was associated with hyperpolarization of Vm and an enhanced galactose but not glucose transport. Acute ethanol and acetaldehyde were without effect on Vm whether or not galactose was present. We conclude that while a greater electrochemical gradient across the brush border membrane is a likely explanation for the stimulation of galactose absorption induced by ethanol feeding, factors other than changes in Vm are responsible for the inhibitory effects of acute ethanol. PMID:2612984

  4. Acute nonhypothermic exposure to cold impedes motor skill performance in video gaming compared to thermo-neutral and hot conditions.

    PubMed

    Edwards, Andrew M; Crowther, Robert G; Morton, R Hugh; Polman, Remco C

    2011-02-01

    The study examined whether or not acute exposure to unfamiliar hot or cold conditions impairs performance of highly skilled coordinative activities and whether prior physical self-efficacy beliefs were associated with task completion. Nineteen volunteers completed both Guitar Hero and Archery activities as a test battery using the Nintendo Wii console in cold (2 degrees C), neutral (20 degrees C), and hot (38 degrees C) conditions. Participants all completed physical self-efficacy questionnaires following experimental familiarization. Performances of both Guitar Hero and Archery significantly decreased in the cold compared with the neutral condition. The cold trial was also perceived as the condition requiring both greater concentration and effort. There was no association between performance and physical self-efficacy. Performance of these coordinative tasks was compromised by acute (nonhypothermic) exposure to cold; the most likely explanation is that the cold condition presented a greater challenge to attentional processes as a form of environmental distraction. PMID:21466095

  5. Life-span exposure to sinusoidal-50 Hz magnetic field and acute low-dose γ radiation induce carcinogenic effects in Sprague-Dawley rats.

    PubMed

    Soffritti, Morando; Tibaldi, Eva; Padovani, Michela; Hoel, David G; Giuliani, Livio; Bua, Luciano; Lauriola, Michelina; Falcioni, Laura; Manservigi, Marco; Manservisi, Fabiana; Panzacchi, Simona; Belpoggi, Fiorella

    2016-01-01

    Background In 2002 the International Agency for Research on Cancer classified extremely low frequency magnetic fields (ELFMF) as a possible carcinogen on the basis of epidemiological evidence. Experimental bioassays on rats and mice performed up to now on ELFMF alone or in association with known carcinogens have failed to provide conclusive confirmation. Objectives To study the carcinogenic effects of combined exposure to sinusoidal-50 Hz (S-50 Hz) magnetic fields and acute γ radiation in Sprague-Dawley rats. Methods We studied groups of male and female Sprague-Dawley rats exposed from prenatal life until natural death to 20 or 1000 μT S-50 Hz MF and also to 0.1 Gy γ radiation delivered as a single acute exposure at 6 weeks of age. Results The results of the study showed significant carcinogenic effects for the mammary gland in males and females and a significant increased incidence of malignant schwannomas of the heart as well as increased incidence of lymphomas/leukemias in males. Conclusions These results call for a re-evaluation of the safety of non-ionizing radiation. PMID:26894944

  6. Progression of micronutrient alteration and hepatotoxicity following acute PCB126 exposure.

    PubMed

    Klaren, W D; Gadupudi, G S; Wels, B; Simmons, D L; Olivier, A K; Robertson, L W

    2015-12-01

    Polychlorinated Biphenyls (PCBs) are industrial chemicals that have become a persistent threat to human health due to ongoing exposure. A subset of PCBs, known as dioxin-like PCBs, pose a special threat given their potent hepatic effects. Micronutrients, especially Cu, Zn and Se, homeostatic dysfunction is commonly seen after exposure to dioxin-like PCBs. This study investigates whether micronutrient alteration is the byproduct of the ongoing hepatotoxicity, marked by lipid accumulation, or a concurrent, yet independent event of hepatic damage. A time course study was carried out using male Sprague-Dawley rats with treatments of PCB126, the prototypical dioxin-like PCB, resulting in 6 different time points. Animals were fed a purified diet, based on AIN-93G, for three weeks to ensure micronutrient equilibration. A single IP injection of either tocopherol-stripped soy oil vehicle (5 mL/kg) or 5 μmol/kg PCB126 dose in vehicle was given at various time points resulting in exposures of 9h, 18 h, 36 h, 3 days, 6 days, and 12 days. Mild hepatic vacuolar change was seen as early as 36 h with drastic changes at the later time points, 6 and 12 days. Micronutrient alterations, specifically Cu, Zn, and Se, were not seen until after day 3 and only observed in the liver. No alterations were seen in the duodenum, suggesting that absorption and excretion may not be involved. Micronutrient alterations occur with ROS formation, lipid accumulation, and hepatomegaly. To probe the mechanistic underpinnings, alteration of gene expression of several copper chaperones was investigated; only metallothionein appeared elevated. These data suggest that the disruption in micronutrient status is a result of the hepatic injury elicited by PCB126 and is mediated in part by metallothionein. PMID:26410179

  7. Exposure Medium: Key in Identifying Free Ag+ as the Exclusive Species of Silver Nanoparticles with Acute Toxicity to Daphnia magna

    PubMed Central

    Shen, Mo-Hai; Zhou, Xiao-Xia; Yang, Xiao-Ya; Chao, Jing-Bo; Liu, Rui; Liu, Jing-Fu

    2015-01-01

    It is still not very clear what roles the various Ag species play in the toxicity of silver nanoparticles (AgNPs). In this study, we found that traditional exposure media result in uncontrollable but consistent physicochemical transformation of AgNPs, causing artifacts in determination of median lethal concentration (LC50) and hindering the identification of Ag species responsible for the acute toxicity of AgNPs to Daphnia magna. This obstacle was overcome by using 8 h exposure in 0.1 mmol L−1 NaNO3 medium, in which we measured the 8-h LC50 of seven AgNPs with different sizes and coatings, and determined the concentrations of various Ag species. The LC50 as free Ag+ of the seven AgNPs (0.37–0.44 μg L−1) agreed very well with that of AgNO3 (0.40 μg L−1), and showed the lowest value compared to that as total Ag, total Ag+, and dissolved Ag, demonstrating free Ag+ is exclusively responsible for the acute toxicity of AgNPs to D. magna, while other Ag species in AgNPs have no contribution to the acute toxicity. Our results demonstrated the great importance of developing appropriate exposure media for evaluating risk of nanomaterials. PMID:25858866

  8. Exposure Medium: Key in Identifying Free Ag+ as the Exclusive Species of Silver Nanoparticles with Acute Toxicity to Daphnia magna

    NASA Astrophysics Data System (ADS)

    Shen, Mo-Hai; Zhou, Xiao-Xia; Yang, Xiao-Ya; Chao, Jing-Bo; Liu, Rui; Liu, Jing-Fu

    2015-04-01

    It is still not very clear what roles the various Ag species play in the toxicity of silver nanoparticles (AgNPs). In this study, we found that traditional exposure media result in uncontrollable but consistent physicochemical transformation of AgNPs, causing artifacts in determination of median lethal concentration (LC50) and hindering the identification of Ag species responsible for the acute toxicity of AgNPs to Daphnia magna. This obstacle was overcome by using 8 h exposure in 0.1 mmol L-1 NaNO3 medium, in which we measured the 8-h LC50 of seven AgNPs with different sizes and coatings, and determined the concentrations of various Ag species. The LC50 as free Ag+ of the seven AgNPs (0.37-0.44 μg L-1) agreed very well with that of AgNO3 (0.40 μg L-1), and showed the lowest value compared to that as total Ag, total Ag+, and dissolved Ag, demonstrating free Ag+ is exclusively responsible for the acute toxicity of AgNPs to D. magna, while other Ag species in AgNPs have no contribution to the acute toxicity. Our results demonstrated the great importance of developing appropriate exposure media for evaluating risk of nanomaterials.

  9. Single dose oral tiaprofenic acid for acute postoperative pain in adults

    PubMed Central

    Moore, R Andrew; Derry, Sheena; Moore, Maura; McQuay, Henry J

    2014-01-01

    Background Tiaprofenic acid is a a non-steroidal anti-inflammatory drug (NSAID). It is widely available around the world, with indications for osteoarthritis, rheumatoid arthritis, ankylosing spondylitis, periarticular disorders, and strains and sprains. This review sought to evaluate the efficacy and safety of oral tiaprofenic acid in acute postoperative pain, using clinical studies of patients with established pain, and with outcomes measured primarily over 6 hours using standard methods. This type of study has been used for many decades to establish that drugs have analgesic properties. Objectives To assess the efficacy of single dose oral tiaprofenic acid in acute postoperative pain, and any associated adverse events. Search methods We searched Cochrane CENTRAL, MEDLINE, EMBASE and the Oxford Pain Relief Database for studies to June 2009. Selection criteria Randomised, double blind, placebo-controlled trials of single dose orally administered tiaprofenic acid in adults with moderate to severe acute postoperative pain. Data collection and analysis Two review authors independently assessed trial quality and extracted data. We planned to use area under the “pain relief versus time” curve to derive the proportion of participants with tiaprofenic acid experiencing at least 50% pain relief over 4 to 6 hours, using validated equations; to use number needed to treat to benefit (NNT); the proportion of participants using rescue analgesia over a specified time period; time to use of rescue analgesia; information on adverse events and withdrawals. Main results Not one of eleven studies identified by the searches and examined in detail studied oral tiaprofenic acid against placebo in patients with established postoperative pain and therefore no results are available. Authors’ conclusions In the absence of evidence of efficacy for oral tiaprofenic acid in acute postoperative pain, its use in this indication is not justified at present. Because trials clearly

  10. Adenylyl cylases 1 and 8 mediate select striatal-dependent behaviors and sensitivity to ethanol stimulation in the adolescent period following acute neonatal ethanol exposure.

    PubMed

    Susick, Laura L; Lowing, Jennifer L; Bosse, Kelly E; Hildebrandt, Clara C; Chrumka, Alexandria C; Conti, Alana C

    2014-08-01

    Neonatal alcohol exposure in rodents causes dramatic neurodegenerative effects throughout the developing nervous system, particularly in the striatum, acutely after exposure. These acute neurodegenerative effects are augmented in mice lacking adenylyl cyclases 1 and 8 (AC1/8) as neonatal mice with a genetic deletion of both AC isoforms (DKO) have increased vulnerability to ethanol-induced striatal neurotoxicity compared to wild type (WT) controls. While neonatal ethanol exposure is known to negatively impact cognitive behaviors, such as executive functioning and working memory in adolescent and adult animals, the threshold of ethanol exposure required to impinge upon developmental behaviors in mice has not been extensively examined. Therefore, the purpose of this study was to determine the behavioral effects of neonatal ethanol exposure using various striatal-dependent developmental benchmarks and to assess the impact of AC1/8 deletion on this developmental progression. WT and DKO mice were treated with 2.5 g/kg ethanol or saline on postnatal day (P)6 and later subjected to the wire suspension, negative geotaxis, postural reflex, grid hang, tail suspension and accelerating rotarod tests at various time points. At P30, mice were evaluated for their hypnotic responses to 4.0 g/kg ethanol by using the loss of righting reflex assay and ethanol-induced stimulation of locomotor activity after 2.0 g/kg ethanol. Ethanol exposure significantly impaired DKO performance in the negative geotaxis test while genetic deletion of AC1/8 alone increased grid hang time and decreased immobility time in the tail suspension test with a concomitant increase in hindlimb clasping behavior. Locomotor stimulation was significantly increased in animals that received ethanol as neonates, peaking significantly in ethanol-treated DKO mice compared to ethanol-treated WT controls, while sedation duration following high-dose ethanol challenge was unaffected. These data indicate that the

  11. Age-related differences in pulmonary effects of acute and subchronic episodic ozone exposures in Brown Norway rats.

    PubMed

    Snow, Samantha J; Gordon, Christopher J; Bass, Virginia L; Schladweiler, Mette C; Ledbetter, Allen D; Jarema, Kimberly A; Phillips, Pamela M; Johnstone, Andrew F; Kodavanti, Urmila P

    2016-06-01

    Ozone (O3) is known to induce adverse pulmonary and systemic health effects. Importantly, children and older persons are considered at-risk populations for O3-induced dysfunction, yet the mechanisms accounting for the age-related pulmonary responses to O3 are uncertain. In this study, we examined age-related susceptibility to O3 using 1 mo (adolescent), 4 mo (young adult), 12 mo (adult) and 24 mo (senescent) male Brown Norway rats exposed to filtered air or O3 (0.25 and 1.00 ppm), 6 h/day, two days/week for 1 week (acute) or 13 weeks (subchronic). Ventilatory function, assessed by whole-body plethysmography, and bronchoalveolar lavage fluid (BALF) biomarkers of injury and inflammation were used to examine O3-induced pulmonary effects. Relaxation time declined in all ages following the weekly exposures; however, this effect persisted only in the 24 mo rats following a five days recovery, demonstrating an inability to induce adaptation commonly seen with repeated O3 exposures. PenH was increased in all groups with an augmented response in the 4 mo rats following the subchronic O3 exposures. O3 led to increased breathing frequency and minute volume in the 1 and 4 mo animals. Markers of pulmonary permeability were increased in all age groups. Elevations in BALF γ-glutamyl transferase activity and lung inflammation following an acute O3 exposure were noted in only the 1 and 4 mo rats, which likely received an increased effective O3 dose. These data demonstrate that adolescent and young adult animals are more susceptible to changes in ventilation and pulmonary injury/inflammation caused by acute and episodic O3 exposure. PMID:27097751

  12. Genetic Aberrations in Childhood Acute Lymphoblastic Leukaemia: Application of High-Density Single Nucleotide Polymorphism Array

    PubMed Central

    Sulong, Sarina

    2010-01-01

    Screening of the entire human genome using high-density single nucleotide polymorphism array (SNPA) has become a powerful technique used in cancer genetics and population genetics studies. The GeneChip® Mapping Array, introduced by Affymetrix, is one SNPA platform utilised for genotyping studies. This GeneChip system allows researchers to gain a comprehensive view of cancer biology on a single platform for the quantification of chromosomal amplifications, deletions, and loss of heterozygosity or for allelic imbalance studies. Importantly, this array analysis has the potential to reveal novel genetic findings involved in the multistep development of cancer. Given the importance of genetic factors in leukaemogenesis and the usefulness of screening the whole genome, SNPA analysis has been utilised in many studies to characterise genetic aberrations in childhood acute lymphoblastic leukaemia. PMID:22135543

  13. Time course of systemic oxidative stress and inflammatory response induced by an acute exposure to Residual Oil Fly Ash

    SciTech Connect

    Marchini, T.; Magnani, N.D.; Paz, M.L.; Vanasco, V.; Tasat, D.; González Maglio, D.H.; and others

    2014-01-15

    It is suggested that systemic oxidative stress and inflammation play a central role in the onset and progression of cardiovascular diseases associated with the exposure to particulate matter (PM). The aim of this work was to evaluate the time changes of systemic markers of oxidative stress and inflammation, after an acute exposure to Residual Oil Fly Ash (ROFA). Female Swiss mice were intranasally instilled with a ROFA suspension (1.0 mg/kg body weight) or saline solution, and plasma levels of oxidative damage markers [thiobarbituric acid reactive substances (TBARSs) and protein carbonyls], antioxidant status [reduced (GSH) and oxidized (GSSG) glutathione, ascorbic acid levels, and superoxide dismutase (SOD) activity], cytokines levels, and intravascular leukocyte activation were evaluated after 1, 3 or 5 h of exposure. Oxidative damage to lipids and decreased GSH/GSSG ratio were observed in ROFA-exposed mice as early as 1 h. Afterwards, increased protein oxidation, decreased ascorbic acid content and SOD activity were found in this group at 3 h. The onset of an adaptive response was observed at 5 h after the ROFA exposure, as indicated by decreased TBARS plasma content and increased SOD activity. The observed increase in oxidative damage to plasma macromolecules, together with systemic antioxidants depletion, may be a consequence of a systemic inflammatory response triggered by the ROFA exposure, since increased TNF-α and IL-6 plasma levels and polymorphonuclear leukocytes activation was found at every evaluated time point. These findings contribute to the understanding of the increase in cardiovascular morbidity and mortality, in association with environmental PM inhalation. - Highlights: • An acute exposure to ROFA triggers the occurrence of systemic oxidative stress. • Changes in plasmatic oxidative stress markers appear as early as 1 h after exposure. • ROFA induces proinflammatory cytokines release and intravascular leukocyte activation. • PMN

  14. Effects of acute single intranasal instillation of secondary organic aerosol on neurological and immunological biomarkers in the brain and lung of BALB/c mice.

    PubMed

    Win-Shwe, Tin-Tin; Fujitani, Yuji; Sone, Hideko; Furuyama, Akiko; Nitta, Hiroshi; Hirano, Seishiro

    2013-02-01

    Recently, we have reported that primary particles from diesel exhaust affect nervous system, immune system, and learning ability in mice. Currently, in vivo and in vitro studies have shown that secondary organic aerosol (SOA) generated from the coal-fired power plant induced adverse effects in lung and heart. However, the effect of SOA on central nervous system is still unknown. In the present study, using potential biomarkers recognized in previous studies of primary particles, we investigated the effect of acute single administration of SOA on the expression levels of various biomarkers in the brain and lung of mice. We generated the SOA by addition of ozone (O(3)) to the diesel exhaust particle (DEP). Eight-week-old male BALB/c mice were administered DEP or DEP+O(3) (SOA) (50 µg/50 µl/mouse) intranasally. Twenty-four hour after acute single exposure to SOA, olfactory bulb, hippocampus and lung from all mice were collected and mRNA expressions of neurological and immunological biomarkers were examined using real-time RT-PCR analysis and histological examination. Proinflammatory cytokines, their transcription factor and neurotrophin mRNA were remarkably increased in lung of mice exposed to SOA but not in the brain. Microarray data showed that changes of the inflammatory reaction and metabolizing enzyme gene cluster were observed in the brain and lung. Our findings suggested that an acute single exposure of SOA does not affect biomarkers in the brain of normal healthy individuals. Our present results also clearly indicate that SOA induces inflammatory responses in the lung by modulating proinflammatory cytokines, transcription factor and inflammatory responsive neurotrophins. PMID:23358141

  15. High Resolution ECG for Evaluation of QT Interval Variability during Exposure to Acute Hypoxia

    NASA Technical Reports Server (NTRS)

    Zupet, P.; Finderle, Z.; Schlegel, Todd T.; Starc, V.

    2010-01-01

    Ventricular repolarization instability as quantified by the index of QT interval variability (QTVI) is one of the best predictors for risk of malignant ventricular arrhythmias and sudden cardiac death. Because it is difficult to appropriately monitor early signs of organ dysfunction at high altitude, we investigated whether high resolution advanced ECG (HR-ECG) analysis might be helpful as a non-invasive and easy-to-use tool for evaluating the risk of cardiac arrhythmias during exposure to acute hypoxia. 19 non-acclimatized healthy trained alpinists (age 37, 8 plus or minus 4,7 years) participated in the study. Five-minute high-resolution 12-lead electrocardiograms (ECGs) were recorded (Cardiosoft) in each subject at rest in the supine position breathing room air and then after breathing 12.5% oxygen for 30 min. For beat-to-beat RR and QT variability, the program of Starc was utilized to derive standard time domain measures such as root mean square of the successive interval difference (rMSSD) of RRV and QTV, the corrected QT interval (QTc) and the QTVI in lead II. Changes were evaluated with paired-samples t-test with p-values less than 0.05 considered statistically significant. As expected, the RR interval and its variability both decreased with increasing altitude, with p = 0.000 and p = 0.005, respectively. Significant increases were found in both the rMSSDQT and the QTVI in lead II, with p = 0.002 and p = 0.003, respectively. There was no change in QTc interval length (p = non significant). QT variability parameters may be useful for evaluating changes in ventricular repolarization caused by hypoxia. These changes might be driven by increases in sympathetic nervous system activity at ventricular level.

  16. IL-22 modulates gut epithelial and immune barrier functions following acute alcohol exposure and burn injury

    PubMed Central

    Rendon, Juan L.; Li, Xiaoling; Akhtar, Suhail; Choudhry, Mashkoor A.

    2012-01-01

    Interleukin (IL)–22 maintains gut epithelial integrity and expression of antimicrobial peptides (AMPs) Reg3β and Reg3γ. Our laboratory has shown that acute alcohol/ethanol (EtOH) exposure prior to burn injury results in increased gut permeability, intestinal T cell suppression and enhanced bacterial translocation. Herein, we determined the effect of combined EtOH intoxication and burn injury on intestinal levels of IL-22 as well as Reg3β and Reg3γ expression. We further examined whether in vivo restitution of IL-22 restores gut permeability, Reg3β and Reg3γ levels, and bacterial load (e.g. gut bacterial growth) within the intestine following EtOH and burn injury. Male mice, ~25g, were gavaged with EtOH (2.9 mg/kg) prior to receiving a ~12.5% total body surface area full thickness burn. Mice were immediately treated with saline control or IL-22 (1 mg/kg) by i.p. injection. One day post injury, there was a significant decrease in intestinal IL-22, Reg3β and Reg3γ expression along with an increase in intestinal permeability and gut bacterial load following EtOH combined with burn injury, as compared to sham injury. Treatment with IL-22 normalized Reg3β and Reg3γ expression, and attenuated the increase in intestinal permeability following EtOH and burn injury. Qualitatively, IL-22 treatment reduced the bacterial load in nearly half of mice receiving EtOH combined with burn injury. Our data indicate that IL-22 maintains gut epithelial and immune barrier integrity following EtOH and burn injury; thus, the IL-22/AMP pathway may provide a therapeutic target for the treatment of patients who sustain burn injury under the influence of EtOH. PMID:23143063

  17. Father's occupational exposure to carcinogenic agents and childhood acute leukemia: a new method to assess exposure (a case-control study)

    PubMed Central

    Perez-Saldivar, Maria Luisa; Ortega-Alvarez, Manuel Carlos; Fajardo-Gutierrez, Arturo; Bernaldez-Rios, Roberto; del Campo-Martinez, Maria de los Angeles; Medina-Sanson, Aurora; Palomo-Colli, Miguel Angel; Paredes-Aguilera, Rogelio; Martínez-Avalos, Armando; Borja-Aburto, Victor Hugo; Rodriguez-Rivera, Maria de Jesus; Vargas-Garcia, Victor Manuel; Zarco-Contreras, Jesus; Flores-Lujano, Janet; Mejia-Arangure, Juan Manuel

    2008-01-01

    Background Medical research has not been able to establish whether a father's occupational exposures are associated with the development of acute leukemia (AL) in their offspring. The studies conducted have weaknesses that have generated a misclassification of such exposure. Occupations and exposures to substances associated with childhood cancer are not very frequently encountered in the general population; thus, the reported risks are both inconsistent and inaccurate. In this study, to assess exposure we used a new method, an exposure index, which took into consideration the industrial branch, specific position, use of protective equipment, substances at work, degree of contact with such substances, and time of exposure. This index allowed us to obtain a grade, which permitted the identification of individuals according to their level of exposure to known or potentially carcinogenic agents that are not necessarily specifically identified as risk factors for leukemia. The aim of this study was to determine the association between a father's occupational exposure to carcinogenic agents and the presence of AL in their offspring. Methods From 1999 to 2000, a case-control study was performed with 193 children who reside in Mexico City and had been diagnosed with AL. The initial sample-size calculation was 150 children per group, assessed with an expected odds ratio (OR) of three and a minimum exposure frequency of 15.8%. These children were matched by age, sex, and institution with 193 pediatric surgical patients at secondary-care hospitals. A questionnaire was used to determine each child's background and the characteristics of the father's occupation(s). In order to determine the level of exposure to carcinogenic agents, a previously validated exposure index (occupational exposure index, OEI) was used. The consistency and validity of the index were assessed by a questionnaire comparison, the sensory recognition of the work area, and an expert's opinion. Results The

  18. Acute-Phase Inflammatory Response to Single-Bout HIIT and Endurance Training: A Comparative Study

    PubMed Central

    Kaspar, Felix; Jelinek, Herbert F.; Perkins, Steven; Al-Aubaidy, Hayder A.; deJong, Bev; Butkowski, Eugene

    2016-01-01

    Objective. This study compared acute and late effect of single-bout endurance training (ET) and high-intensity interval training (HIIT) on the plasma levels of four inflammatory cytokines and C-reactive protein and insulin-like growth factor 1. Design. Cohort study with repeated-measures design. Methods. Seven healthy untrained volunteers completed a single bout of ET and HIIT on a cycle ergometer. ET and HIIT sessions were held in random order and at least 7 days apart. Blood was drawn before the interventions and 30 min and 2 days after the training sessions. Plasma samples were analyzed with ELISA for the interleukins (IL), IL-1β, IL-6, and IL-10, monocyte chemoattractant protein-1 (MCP-1), insulin growth factor 1 (IGF-1), and C-reactive protein (CRP). Statistical analysis was with Wilcoxon signed-rank tests. Results. ET led to both a significant acute and long-term inflammatory response with a significant decrease at 30 minutes after exercise in the IL-6/IL-10 ratio (−20%; p = 0.047) and a decrease of MCP-1 (−17.9%; p = 0.03). Conclusion. This study demonstrates that ET affects the inflammatory response more adversely at 30 minutes after exercise compared to HIIT. However, this is compensated by a significant decrease in MCP-1 at two days associated with a reduced risk of atherosclerosis. PMID:27212809

  19. Acute-Phase Inflammatory Response to Single-Bout HIIT and Endurance Training: A Comparative Study.

    PubMed

    Kaspar, Felix; Jelinek, Herbert F; Perkins, Steven; Al-Aubaidy, Hayder A; deJong, Bev; Butkowski, Eugene

    2016-01-01

    Objective. This study compared acute and late effect of single-bout endurance training (ET) and high-intensity interval training (HIIT) on the plasma levels of four inflammatory cytokines and C-reactive protein and insulin-like growth factor 1. Design. Cohort study with repeated-measures design. Methods. Seven healthy untrained volunteers completed a single bout of ET and HIIT on a cycle ergometer. ET and HIIT sessions were held in random order and at least 7 days apart. Blood was drawn before the interventions and 30 min and 2 days after the training sessions. Plasma samples were analyzed with ELISA for the interleukins (IL), IL-1β, IL-6, and IL-10, monocyte chemoattractant protein-1 (MCP-1), insulin growth factor 1 (IGF-1), and C-reactive protein (CRP). Statistical analysis was with Wilcoxon signed-rank tests. Results. ET led to both a significant acute and long-term inflammatory response with a significant decrease at 30 minutes after exercise in the IL-6/IL-10 ratio (-20%; p = 0.047) and a decrease of MCP-1 (-17.9%; p = 0.03). Conclusion. This study demonstrates that ET affects the inflammatory response more adversely at 30 minutes after exercise compared to HIIT. However, this is compensated by a significant decrease in MCP-1 at two days associated with a reduced risk of atherosclerosis. PMID:27212809

  20. ACCUMULATION OF M1DG DNA ADDUCTS AFTER CHRONIC EXPOSURE TO PCBS, BUT NOT FROM ACUTE EXPOSURE TO DIOXIN-LIKE COMPOUNDS

    EPA Science Inventory

    ABSTRACT: Oxidative DNA damage is one of the key events leading to mutation and cancer. The present study examined the accumulation of M1dG DNA adducts, 3-(2’-deoxy-β-D-erythro-pentofuranosyl)-pyrimido[1,2-a]-purin-10(3H)-one, after single or yearly exposur...

  1. Development and application of acute exposure guideline levels (AEGLs) for chemical warfare nerve and sulfur mustard agents.

    PubMed

    Watson, Annetta; Opresko, Dennis; Young, Robert; Hauschild, Veronique

    2006-01-01

    Acute exposure guideline levels (AEGLs) have been developed for the chemical warfare agents GB, GA, GD, GF, VX, and sulfur mustard. These AEGLs were approved by the National Advisory Committee for Acute Exposure Guideline Levels for Hazardous Substances after Federal Register publication and comment, and judged as scientifically valid by the National Research Council Committee on Toxicology Subcommittee on AEGLs. AEGLs represent general public exposure limits for durations ranging from 10 min to 8 h, and for three levels of severity (AEGL-1, AEGL-2, AEGL-3). Mild effects are possible at concentrations greater than AEGL-1, while life-threatening effects are expected at concentrations greater than AEGL-3. AEGLs can be applied to various civilian and national defense purposes, including evacuation and shelter-in-place protocols, reentry levels, protective clothing specifications, and analytical monitoring requirements. This report documents development and derivation of AEGL values for six key chemical warfare agents, and makes recommendations for their application to various potential exposure scenarios. PMID:16621779

  2. Effects of acute fresh water exposure on water flux rates and osmotic responses in Kemp's ridley sea turtles (Lepidochelys kempi)

    NASA Technical Reports Server (NTRS)

    Ortiz, R. M.; Patterson, R. M.; Wade, C. E.; Byers, F. M.

    2000-01-01

    Water flux rates and osmotic responses of Kemp's Ridley sea turtles (Lepidochelys kempi) acutely exposed to fresh water were quantified. Salt-water adapted turtles were exposed to fresh water for 4 d before being returned to salt water. During the initial salt water phase, absolute and relative water flux rates were 1.2+/-0.1 l d(-1) and 123.0+/-6.8 ml kg(-1) d(-1), respectively. When turtles were exposed to fresh water, rates increased by approximately 30%. Upon return to salt water, rates decreased to original levels. Plasma osmolality, Na(+), K(+), and Cl(-) decreased during exposure to fresh water, and subsequently increased during the return to salt water. The Na(+):K(+) ratio was elevated during the fresh water phase and subsequently decreased upon return to salt water. Aldosterone and corticosterone were not altered during exposure to fresh water. Elevated water flux rates during fresh water exposure reflected an increase in water consumption, resulting in a decrease in ionic and osmotic concentrations. The lack of a change in adrenocorticoids to acute fresh water exposure suggests that adrenal responsiveness to an hypo-osmotic environment may be delayed in marine turtles when compared to marine mammals.

  3. Development and Application of Acute Exposure Guideline Levels (AEGLs) for Chemical Warfare Nerve and Sulfur Mustard Agents.

    SciTech Connect

    Watson, Annetta Paule; Opresko, Dennis M; Young, Robert A; Hauschild, Veronique

    2006-01-01

    Acute exposure guideline levels (AEGLs) have been developed for the chemical warfare agents GB, GA, GD, GF, VX, and sulfur mustard. These AEGLs were approved by the National Advisory Committee for Acute Exposure Guideline Levels for Hazardous Substances after Federal Register publication and comment, and judged as scientifically valid by the National Research Council Committee on Toxicology Subcommittee on AEGLs. AEGLs represent general public exposure limits for durations ranging from 10 min to 8 h, and for three levels of severity (AEGL-1, AEGL-2, AEGL-3). Mild effects are possible at concentrations greater than AEGL-1, while life-threatening effects are expected at concentrations greater than AEGL-3. AEGLs can be applied to various civilian and national defense purposes, including evacuation and shelter-in-place protocols, reentry levels, protective clothing specifications, and analytical monitoring requirements. This report documents development and derivation of AEGL values for six key chemical warfare agents, and makes recommendations for their application to various potential exposure scenarios.

  4. Effect of acute/subchronic samarium exposure on the concentration, motility, and morphology of sperm in male mice.

    PubMed

    Zhang, D Y; Shen, X Y; Xu, X L; Ruan, Q; Hu, S S; Chen, Y Y; Wang, Z M

    2016-01-01

    Male ICR mice were orally administered samarium nitrate [Sm(NO3)3] to investigate its effects on sperm concentration and sperm quality. After acute exposure to ≥2880.00 mg/kg Sm(NO3)3 via intragastric gavage, sperm motility and acrosome integrity were decreased, and the sperm malformation percentage was increased (P < 0.05). After subchronic exposure to ≥500.00 mg/L Sm(NO3)3 administered via drinking water for 90 days, relative gonad weight, sperm concentration, and sperm quality significantly decreased (P < 0.05). Sperm malformation also increased after subchronic exposure to Sm, which was found to be the most sensitive index. Sperm head malformation accounted for the largest proportion of all types of sperm malformations evaluated. Of the six different subtypes of head malformation, irregular shape accounted for the largest proportion. PMID:27420955

  5. Dissecting the clonal origins of childhood acute lymphoblastic leukemia by single-cell genomics

    PubMed Central

    Gawad, Charles; Koh, Winston; Quake, Stephen R.

    2014-01-01

    Many cancers have substantial genomic heterogeneity within a given tumor, and to fully understand that diversity requires the ability to perform single cell analysis. We performed targeted sequencing of a panel of single nucleotide variants (SNVs), deletions, and IgH sequences in 1,479 single tumor cells from six acute lymphoblastic leukemia (ALL) patients. By accurately segregating groups of cooccurring mutations into distinct clonal populations, we identified codominant clones in the majority of patients. Evaluation of intraclonal mutation patterns identified clone-specific punctuated cytosine mutagenesis events, showed that most structural variants are acquired before SNVs, determined that KRAS mutations occur late in disease development but are not sufficient for clonal dominance, and identified clones within the same patient that are arrested at varied stages in B-cell development. Taken together, these data order the sequence of genetic events that underlie childhood ALL and provide a framework for understanding the development of the disease at single-cell resolution. PMID:25425670

  6. Pulmonary Responses of Sprague-Dawley Rats in Single Inhalation Exposure to Graphene Oxide Nanomaterials

    PubMed Central

    Han, Sung Gu; Kim, Jin Kwon; Shin, Jae Hoon; Hwang, Joo Hwan; Lee, Jong Seong; Kim, Tae-Gyu; Lee, Ji Hyun; Lee, Gun Ho; Kim, Keun Soo; Lee, Heon Sang; Song, Nam Woong; Ahn, Kangho; Yu, Il Je

    2015-01-01

    Graphene is receiving increased attention due to its potential widespread applications in future. However, the health effects of graphene have not yet been well studied. Therefore, this study examined the pulmonary effects of graphene oxide using male Sprague-Dawley rats and a single 6-hour nose-only inhalation technique. Following the exposure, the rats were allowed to recover for 1 day, 7 days, or 14 days. A total of three groups were compared: control (fresh air), low concentration (0.46 ± 0.06 mg/m3), and high concentration (3.76 ± 0.24 mg/m3). The exposure to graphene oxide did not induce significant changes in the body weights, organ weights, and food consumption during the 14 days of recovery time. The microalbumin and lactate dehydrogenase levels in the bronchoalveolar lavage (BAL) fluid were not significantly changed due to the exposure. Similarly, total cell count, macrophages, polymorphonuclear leukocytes, and lymphocytes were not significantly altered in the BAL fluid. Plus, the histopathological examination of the rat lungs only showed an uptake of graphene oxide in the alveolar macrophages of the high-concentration group. Therefore, these results demonstrate that the single inhalation exposure to graphene oxide induce minimal toxic responses in rat lungs at the concentrations and time points used in the present study. PMID:26295037

  7. Large-Scale Analysis of Acute Ethanol Exposure in Zebrafish Development: A Critical Time Window and Resilience

    PubMed Central

    Ali, Shaukat; Champagne, Danielle L.; Alia, Alia; Richardson, Michael K.

    2011-01-01

    Background In humans, ethanol exposure during pregnancy causes a spectrum of developmental defects (fetal alcohol syndrome or FAS). Individuals vary in phenotypic expression. Zebrafish embryos develop FAS-like features after ethanol exposure. In this study, we ask whether stage-specific effects of ethanol can be identified in the zebrafish, and if so, whether they allow the pinpointing of sensitive developmental mechanisms. We have therefore conducted the first large-scale (>1500 embryos) analysis of acute, stage-specific drug effects on zebrafish development, with a large panel of readouts. Methodology/Principal Findings Zebrafish embryos were raised in 96-well plates. Range-finding indicated that 10% ethanol for 1 h was suitable for an acute exposure regime. High-resolution magic-angle spinning proton magnetic resonance spectroscopy showed that this produced a transient pulse of 0.86% concentration of ethanol in the embryo within the chorion. Survivors at 5 days postfertilisation were analysed. Phenotypes ranged from normal (resilient) to severely malformed. Ethanol exposure at early stages caused high mortality (≥88%). At later stages of exposure, mortality declined and malformations developed. Pharyngeal arch hypoplasia and behavioral impairment were most common after prim-6 and prim-16 exposure. By contrast, microphthalmia and growth retardation were stage-independent. Conclusions Our findings show that some ethanol effects are strongly stage-dependent. The phenotypes mimic key aspects of FAS including craniofacial abnormality, microphthalmia, growth retardation and behavioral impairment. We also identify a critical time window (prim-6 and prim-16) for ethanol sensitivity. Finally, our identification of a wide phenotypic spectrum is reminiscent of human FAS, and may provide a useful model for studying disease resilience. PMID:21625530

  8. No acute toxicity to Uca pugnax, the mud fiddler crab, following a 96-h exposure to sediment-bound permethrin.

    PubMed

    Stueckle, Todd A; Griffin, Kristin; Foran, Christy M

    2008-08-01

    In coastal areas, the application of pyrethroid insecticides and the resulting sediment residues pose a potential threat to marine benthic ecosystems. Pyrethroids cause acute toxicity and exhibit a wide range of sublethal effects on fish and crustaceans when exposure is aqueous. Fiddler crabs that inhabit salt marsh sediment are sensitive to sediment-associated pollutants and serve as a sentinel species for xenobiotic exposure. We exposed adult U. pugnax to salt marsh sediment spiked with different 60% trans/40% cis permethrin concentrations for 96 h, and evaluated changes in oxygen consumption rate, hemolymph osmolarity, and glutathione S-transferase activity (GST) following exposure. Marsh sediment was not lethal to U. pugnax at permethrin concentrations of 100-10,000 microg/kg. Sediment-bound permethrin had no significant effect on respiration and osmoregulation. Exposure caused an induction of hepatopancreas GST in a dose-dependent manner. Gill and midgut tissues showed induction at permethrin concentrations at 10,000 microg/kg. We conclude that short term exposure to permethrin-contaminated sediment does not pose a significant threat to this species or impact respiration and osmoregulation. Furthermore, increased GST activity allows us to evaluate this enzyme's induction as a generalist biomarker for sediment-bound pyrethroid exposures. PMID:18214939

  9. Acute Toluene Exposure alters expression of genes associated with synaptic structure and function

    EPA Science Inventory

    Toluene (TOL), a volatile organic compound, is a ubiquitous air pollutant of interest to EPA regulatory programs. Whereas its acute functional effects are well described, several potential modes of action in the CNS have been proposed. Therefore, the genomic response to acute TOL...

  10. Single Clinical Isolates from Acute Uncomplicated Urinary Tract Infections Are Representative of Dominant In Situ Populations

    PubMed Central

    Willner, Dana; Low, Serene; Steen, Jason A.; George, Narelle; Nimmo, Graeme R.; Schembri, Mark A.; Hugenholtz, Philip

    2014-01-01

    ABSTRACT Urinary tract infections (UTIs) are one of the most commonly acquired bacterial infections in humans, and uropathogenic Escherichia coli strains are responsible for over 80% of all cases. The standard method for identification of uropathogens in clinical laboratories is cultivation, primarily using solid growth media under aerobic conditions, coupled with morphological and biochemical tests of typically a single isolate colony. However, these methods detect only culturable microorganisms, and characterization is phenotypic in nature. Here, we explored the genotypic identity of communities in acute uncomplicated UTIs from 50 individuals by using culture-independent amplicon pyrosequencing and whole-genome and metagenomic shotgun sequencing. Genus-level characterization of the UTI communities was achieved using the 16S rRNA gene (V8 region). Overall UTI community richness was very low in comparison to other human microbiomes. We strain-typed Escherichia-dominated UTIs using amplicon pyrosequencing of the fimbrial adhesin gene, fimH. There were nine highly abundant fimH types, and each UTI sample was dominated by a single type. Molecular analysis of the corresponding clinical isolates revealed that in the majority of cases the isolate was representative of the dominant taxon in the community at both the genus and the strain level. Shotgun sequencing was performed on a subset of eight E. coli urine UTI and isolate pairs. The majority of UTI microbial metagenomic sequences mapped to isolate genomes, confirming the results obtained using phylogenetic markers. We conclude that for the majority of acute uncomplicated E. coli-mediated UTIs, single cultured isolates are diagnostic of the infection. PMID:24570371

  11. Acute invasive pulmonary aspergillosis, shortly after occupational exposure to polluted muddy water, in a previously healthy subject

    PubMed Central

    Pilaniya, Vikas; Gera, Kamal; Gothi, Rajesh; Shah, Ashok

    2015-01-01

    Invasive pulmonary aspergillosis (IPA) predominantly occurs in severely neutropenic immunocompromised subjects. The occurrence of acute IPA after brief but massive exposure to Aspergillus conidia in previously healthy subjects has been documented, although only six such cases have been reported. The diagnosis was delayed in all six of the affected patients, five of whom died. We report the case of a 50-year-old HIV-negative male, a water pipeline maintenance worker, who presented with acute-onset dyspnea and fever one day after working for 2 h in a deep pit containing polluted, muddy water. Over a one-month period, his general condition deteriorated markedly, despite antibiotic therapy. Imaging showed bilateral diffuse nodules with cavitation, some of which were surrounded by ground-glass opacity suggestive of a halo sign (a hallmark of IPA). Cultures (of sputum/bronchial aspirate samples) and serology were positive for Aspergillus fumigatus. After being started on itraconazole, the patient improved. We conclude that massive exposure to Aspergillus conidia can lead to acute IPA in immunocompetent subjects. PMID:26578140

  12. An incident study about acute and chronic human exposure to uranium by high-resolution inductively coupled plasma mass spectrometry (HR-ICPMS).

    PubMed

    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

  13. SYSTEMIC IMBALANCE OF ESSENTIAL METALS AND CARDIAC GENE EXPRESSION IN RATS FOLLOWING ACUTE PULMONARY ZINC EXPOSURE

    EPA Science Inventory

    We have recently demonstrated that PM containing water-soluble zinc may cause cardiac injury following pulmonary exposure. To investigate if pulmonary zinc exposure causes systemic metal imbalance and direct cardiac effects, we intratracheally (IT) instilled male Wistar Kyoto (WK...

  14. Response of cardiac autonomic modulation after a single exposure to musical auditory stimulation.

    PubMed

    Ferreira, Lucas L; Vanderlei, Luiz Carlos M; Guida, Heraldo L; de Abreu, Luiz Carlos; Garner, David M; Vanderlei, Franciele M; Ferreira, Celso; Valenti, Vitor E

    2015-01-01

    The acute effects after exposure to different styles of music on cardiac autonomic modulation assessed through heart rate variability (HRV) analysis have not yet been well elucidated. We aimed to investigate the recovery response of cardiac autonomic modulation in women after exposure to musical auditory stimulation of different styles. The study was conducted on 30 healthy women aged between 18 years and 30 years. We did not include subjects having previous experience with musical instruments and those who had an affinity for music styles. The volunteers remained at rest for 10 min and were exposed to classical baroque (64-84 dB) and heavy metal (75-84 dB) music for 10 min, and their HRV was evaluated for 30 min after music cessation. We analyzed the following HRV indices: Standard deviation of normal-to-normal (SDNN) intervals, root mean square of successive differences (RMSSD), percentage of normal-to-normal 50 (pNN50), low frequency (LF), high frequency (HF), and LF/HF ratio. SDNN, LF in absolute units (ms 2 ) and normalized (nu), and LF/HF ratio increased while HF index (nu) decreased after exposure to classical baroque music. Regarding the heavy metal music style, it was observed that there were increases in SDNN, RMSSD, pNN50, and LF (ms 2 ) after the musical stimulation. In conclusion, the recovery response of cardiac autonomic modulation after exposure to auditory stimulation with music featured an increased global activity of both systems for the two musical styles, with a cardiac sympathetic modulation for classical baroque music and a cardiac vagal tone for the heavy metal style. PMID:25774614

  15. Response of cardiac autonomic modulation after a single exposure to musical auditory stimulation

    PubMed Central

    Ferreira, Lucas L.; Vanderlei, Luiz Carlos M.; Guida, Heraldo L.; de Abreu, Luiz Carlos; Garner, David M.; Vanderlei, Franciele M.; Ferreira, Celso; Valenti, Vitor E.

    2015-01-01

    The acute effects after exposure to different styles of music on cardiac autonomic modulation assessed through heart rate variability (HRV) analysis have not yet been well elucidated. We aimed to investigate the recovery response of cardiac autonomic modulation in women after exposure to musical auditory stimulation of different styles. The study was conducted on 30 healthy women aged between 18 years and 30 years. We did not include subjects having previous experience with musical instruments and those who had an affinity for music styles. The volunteers remained at rest for 10 min and were exposed to classical baroque (64-84 dB) and heavy metal (75-84 dB) music for 10 min, and their HRV was evaluated for 30 min after music cessation. We analyzed the following HRV indices: Standard deviation of normal-to-normal (SDNN) intervals, root mean square of successive differences (RMSSD), percentage of normal-to-normal 50 (pNN50), low frequency (LF), high frequency (HF), and LF/HF ratio. SDNN, LF in absolute units (ms2) and normalized (nu), and LF/HF ratio increased while HF index (nu) decreased after exposure to classical baroque music. Regarding the heavy metal music style, it was observed that there were increases in SDNN, RMSSD, pNN50, and LF (ms2) after the musical stimulation. In conclusion, the recovery response of cardiac autonomic modulation after exposure to auditory stimulation with music featured an increased global activity of both systems for the two musical styles, with a cardiac sympathetic modulation for classical baroque music and a cardiac vagal tone for the heavy metal style. PMID:25774614

  16. Single site multiport umbilical laparoscopic appendicectomy versus conventional multiport laparoscopic appendicectomy in acute settings

    PubMed Central

    Yadav, SP

    2014-01-01

    Introduction Although conventional multiport laparoscopic appendicectomy (CMLA) is preferred for managing acute appendicitis, the recently developed transumbilical laparoscopic approach is rapidly gaining popularity. However, its wide dissemination seems restricted by technical/technological issues. In this regard, a newly developed method of single site multiport umbilical laparoscopic appendicectomy (SMULA) was compared prospectively with CMLA to assess the former’s efficacy and the technical advantages in acute scenarios. Methods Overall, 430 patients were studied: 212 in the SMULA group and 218 in the CMLA group. The same surgeon performed all the procedures using routine laparoscopic instruments. The SMULA technique entailed three ports inserted directly at the umbilical mound through three distinct strategically placed mini-incisions without raising the umbilical flap. The CMLA involved the traditional three-port technique. Results Both groups were comparable in terms of demographic criteria, indications for surgery, intraoperative blood loss, time to ambulation, length of hospital stay and umbilical morbidity. Although the mean operative time was marginally longer in the SMULA group (43.35 minutes, standard deviation [SD]: 21.16 minutes) than in the CMLA group (42.28 minutes, SD: 21.41 minutes), this did not reach statistical significance. Conversely, the mean pain scores on day 0 and the cosmetic outcomes differed significantly and favoured the SMULA technique. None of the patients developed port site hernias over the follow-up period (mean 2.9 years). Conclusions The favourable outcomes for the SMULA technique are likely to be due to the three small segregated incisions at one place and better trocar ergonomics. The SMULA technique is safe in an acute setting and may be considered of value among the options for transumbilical appendicectomy. PMID:25198978

  17. Microarray characterization of gene expression changes in blood during acute ethanol exposure

    PubMed Central

    2013-01-01

    Background As part of the civil aviation safety program to define the adverse effects of ethanol on flying performance, we performed a DNA microarray analysis of human whole blood samples from a five-time point study of subjects administered ethanol orally, followed by breathalyzer analysis, to monitor blood alcohol concentration (BAC) to discover significant gene expression changes in response to the ethanol exposure. Methods Subjects were administered either orange juice or orange juice with ethanol. Blood samples were taken based on BAC and total RNA was isolated from PaxGene™ blood tubes. The amplified cDNA was used in microarray and quantitative real-time polymerase chain reaction (RT-qPCR) analyses to evaluate differential gene expression. Microarray data was analyzed in a pipeline fashion to summarize and normalize and the results evaluated for relative expression across time points with multiple methods. Candidate genes showing distinctive expression patterns in response to ethanol were clustered by pattern and further analyzed for related function, pathway membership and common transcription factor binding within and across clusters. RT-qPCR was used with representative genes to confirm relative transcript levels across time to those detected in microarrays. Results Microarray analysis of samples representing 0%, 0.04%, 0.08%, return to 0.04%, and 0.02% wt/vol BAC showed that changes in gene expression could be detected across the time course. The expression changes were verified by qRT-PCR. The candidate genes of interest (GOI) identified from the microarray analysis and clustered by expression pattern across the five BAC points showed seven coordinately expressed groups. Analysis showed function-based networks, shared transcription factor binding sites and signaling pathways for members of the clusters. These include hematological functions, innate immunity and inflammation functions, metabolic functions expected of ethanol metabolism, and pancreatic

  18. Acute Free-Iron Exposure Does Not Explain the Impaired Haemorheology Associated with Haemochromatosis

    PubMed Central

    McNamee, Antony P.; Sabapathy, Surendran; Singh, Indu; Horobin, Jarod; Guerrero, Janelle; Simmonds, Michael J.

    2016-01-01

    . Acute exposure to elevated iron levels does not appear (in isolation) to account for these differences. Further consideration is required prior to utilising routine venesection blood for harvesting RBC concentrates due to the potential risk of microvascular disorders arising from impaired haemorheology. PMID:26741993

  19. The toxicity of acute exposure to T-2 toxin evaluated by the metabonomics technique.

    PubMed

    Wan, Qianfen; Wu, Guangyao; He, Qinghua; Tang, Huiru; Wang, Yulan

    2015-03-01

    T-2 toxin is a common contaminant in grains and animal feedstuff, which becomes an increasing threat to human and animal health due to its high toxicity. Investigating the systemic effects of T-2 toxin is important to evaluate the toxicity and facilitate the assessment of food safety. In our investigation, rats were treated with a single dose of T-2 toxin at dosage levels of 0, 0.5, 2.0 and 4.0 mg kg(-1) body weight via gavage. The metabolic profiles of body fluids and multiple organs were obtained by NMR spectroscopy and analyzed by multivariate data analysis methods. The results showed that low and moderate doses of T-2 toxin only influenced the urinary metabonomes, while a high dose of T-2 toxin induced metabolic alterations in urine and multiple organs. These changes included alterations in the levels of membrane metabolites, TCA cycle intermediates, a range of amino acids, nucleosides and nucleotides. T-2 toxin exposure impaired spleen function, causing immunotoxicity, and inhibited protein and DNA biosynthesis. In addition, T-2 toxin also caused oxidative stress and disturbance in energy metabolism and gut microbiome. Our work provided a comprehensive insight into T-2 toxicity and revealed the great potential of metabonomics in assessing the impact of a toxic compound. PMID:25588579

  20. Assessment of visual function and retinal structure following acute light exposure in the light sensitive T4R rhodopsin mutant dog.

    PubMed

    Iwabe, Simone; Ying, Gui-Shuang; Aguirre, Gustavo D; Beltran, William A

    2016-05-01

    The effect of acute exposure to various intensities of white light on visual behavior and retinal structure was evaluated in the T4R RHO dog, a naturally-occurring model of autosomal dominant retinitis pigmentosa due to a mutation in the Rhodopsin gene. A total of 14 dogs (ages: 4-5.5 months) were used in this study: 3 homozygous mutant RHO(T4R/T4R), 8 heterozygous mutant RHO(T4R/+), and 3 normal wild-type (WT) dogs. Following overnight dark adaptation, the left eyes were acutely exposed to bright white light with a monocular Ganzfeld dome, while the contralateral right eye was shielded. Each of the 3 homozygous (RHO(T4R/T4R)) mutant dogs had a single unilateral light exposure (LE) to a different (low, moderate, and high) dose of white light (corneal irradiance/illuminance: 0.1 mW/cm(2), 170 lux; 0.5 mW/cm(2), 820 lux; or 1 mW/cm(2), 1590 lux) for 1 min. All 8 heterozygous (RHO(T4R/+)) mutant dogs were exposed once to the same moderate dose of light. The 3 WT dogs had their left eyes exposed 1, 2, or 3 times to the same highest dose of light. Visual function prior to LE and at 2 weeks and 33 weeks after exposure was objectively assessed in the RHO(T4R/T4R) and WT dogs by using an obstacle-avoidance course. Transit time through the obstacle course was measured under different scotopic to photopic ambient illuminations. Morphological retinal changes were evaluated by non-invasive in vivo cSLO/sdOCT imaging and histology before and at several time-points (2-36 weeks) after light exposure. The analysis of the transit time through the obstacle course showed that no differences were observed in any of mutant or WT dogs at 2 weeks and 33 weeks post LE. The RHO(T4R/T4R) retina exposed to the lowest dose of white light showed no obvious changes in ONL thickness at 2 weeks, but mild decrease was noted 36 weeks after LE. The RHO(T4R/T4R) retina that received a moderate dose (showed an obvious decrease in ONL thickness along the superior and temporal meridians at 2

  1. ASSESSMENT OF VISUAL FUNCTION AND RETINAL STRUCTURE FOLLOWING ACUTE LIGHT EXPOSURE IN THE LIGHT SENSITIVE T4R RHODOPSIN MUTANT DOG

    PubMed Central

    Iwabe, Simone; Ying, Gui-Shuang; Aguirre, Gustavo D.; Beltran, William A.

    2016-01-01

    The effect of acute exposure to various intensities of white light on visual behavior and retinal structure was evaluated in the T4R RHO dog, a naturally-occurring model of autosomal dominant retinitis pigmentosa due to a mutation in the Rhodopsin gene. A total of 14 dogs (ages: 4–5.5 months) were used in this study: 3 homozygous mutant RHOT4R/T4R, 8 heterozygous mutant RHOT4R/+, and 3 normal wild-type (WT) dogs. Following overnight dark adaptation, the left eyes were acutely exposed to bright white light with a monocular Ganzfeld dome, while the contralateral right eye was shielded. Each of the 3 homozygous (RHOT4R/T4R) mutant dogs had a single unilateral light exposure (LE) to a different (low, moderate, and high) dose of white light (corneal irradiance/illuminance: 0.1 mW/cm2, 170 lux; 0.5 mW/cm2, 820 lux; or 1 mW/cm2, 1590 lux) for 1min. All 8 heterozygous (RHOT4R/+) mutant dogs were exposed once to the same moderate dose of light. The 3 WT dogs had their left eyes exposed 1, 2, or 3 times to the same highest dose of light. Visual function prior to LE and at 2 weeks and 33 weeks after exposure was objectively assessed in the RHOT4R/T4R and WT dogs by using an obstacle-avoidance course. Transit time through the obstacle course was measured under different scotopic to photopic ambient illuminations. Morphological retinal changes were evaluated by non-invasive in vivo cSLO/sdOCT imaging and histology before and at several time-points (2–36 weeks) after light exposure. The analysis of the transit time through the obstacle course showed that no differences were observed in any of mutant or WT dogs at 2 weeks and 33 weeks post LE. The RHOT4R/T4R retina exposed to the lowest dose of white light showed no obvious changes in ONL thickness at 2 weeks, but mild decrease was noted 36 weeks after LE. The RHOT4R/T4R retina that received a moderate dose (showed an obvious decrease in ONL thickness along the superior and temporal meridians at 2 weeks post LE with more

  2. Rapidly Progressing Severe Cutaneous Adverse Reaction With Acute Kidney Injury After Drug Exposure: An Uncommon Presentation.

    PubMed

    Rodgers, Bradley K; Kumar, Avinash B

    2016-01-01

    Toxic epidermal necrolysis syndrome (TEN) is a rare severe cutaneous adverse drug reaction that involves skin and mucous membranes. We describe a case of TEN presenting with stage III acute kidney injury, rhabdomyolysis, and acute respiratory failure likely triggered by allopurinol for recently diagnosed gout. Prompt diagnosis, multidisciplinary management, including aggressive resuscitation, cardiorespiratory support, intravenous immunoglobulin therapy, and daily wound care resulted in a positive outcome despite a predicted mortality greater than 60%. Although allopurinol is a known triggering agent, TEN presenting with rhabdomyolysis and acute kidney injury is rare. PMID:24832386

  3. Acute effects of single-dose olanzapine on metabolic, endocrine, and inflammatory markers in healthy controls.

    PubMed

    Hahn, Margaret Karolina; Wolever, Tom M S; Arenovich, Tamara; Teo, Celine; Giacca, Adria; Powell, Valerie; Clarke, Leigh; Fletcher, Paul; Cohn, Tony; McIntyre, Roger S; Gomes, Sylvia; Chintoh, Araba; Remington, Gary J

    2013-12-01

    Atypical antipsychotics may "directly" influence glucose homeostasis, increasing risk of type 2 diabetes independently of changes in adiposity. Animal models suggest direct effects after even a single dose of certain atypical antipsychotics on glucose dysregulation. Here, we investigated effects of a single-dose olanzapine (OLA) on glucose metabolism in healthy volunteers, thereby minimizing confounding effects of the illness of schizophrenia and adiposity. In a randomized double-blind crossover design, 15 subjects were administered 10 mg of OLA or placebo at 7:00 A.M. on separate study dates. A frequently sampled intravenous glucose tolerance test was initiated 4.25 hours later to assess changes in glucose homeostasis, including an index of insulin sensitivity, disposition index, glucose effectiveness, and acute insulin response to glucose. We also examined effects on cortisol, prolactin, fasting free fatty acids (FFAs), insulin-mediated suppression of FFAs, and adipocytokines (leptin, adiponectin, C-reactive protein, interleukin 6, and tumor necrosis factor α). Complete data for both visits were analyzed for 12 subjects. Olanzapine treatment significantly decreased glucose effectiveness (P = 0.041) and raised fasting glucose over 4.25 hours (P = 0.03) as compared to placebo. Olanzapine was associated with lower serum cortisol (P = 0.003), lower fasting FFA (P = 0.042), and increased prolactin levels (P < 0.0001). We therefore suggest that a single dose of OLA may invoke early changes in some parameters of glucose and lipid metabolism, as well as endocrine indices. PMID:24100786

  4. Clonal Architecture of Secondary Acute Myeloid Leukemia Defined by Single-Cell Sequencing

    PubMed Central

    Hughes, Andrew E. O.; Magrini, Vincent; Demeter, Ryan; Miller, Christopher A.; Fulton, Robert; Fulton, Lucinda L.; Eades, William C.; Elliott, Kevin; Heath, Sharon; Westervelt, Peter; Ding, Li; Conrad, Donald F.; White, Brian S.; Shao, Jin; Link, Daniel C.; DiPersio, John F.; Mardis, Elaine R.; Wilson, Richard K.; Ley, Timothy J.; Walter, Matthew J.; Graubert, Timothy A.

    2014-01-01

    Next-generation sequencing has been used to infer the clonality of heterogeneous tumor samples. These analyses yield specific predictions—the population frequency of individual clones, their genetic composition, and their evolutionary relationships—which we set out to test by sequencing individual cells from three subjects diagnosed with secondary acute myeloid leukemia, each of whom had been previously characterized by whole genome sequencing of unfractionated tumor samples. Single-cell mutation profiling strongly supported the clonal architecture implied by the analysis of bulk material. In addition, it resolved the clonal assignment of single nucleotide variants that had been initially ambiguous and identified areas of previously unappreciated complexity. Accordingly, we find that many of the key assumptions underlying the analysis of tumor clonality by deep sequencing of unfractionated material are valid. Furthermore, we illustrate a single-cell sequencing strategy for interrogating the clonal relationships among known variants that is cost-effective, scalable, and adaptable to the analysis of both hematopoietic and solid tumors, or any heterogeneous population of cells. PMID:25010716

  5. Quantifying Fish Swimming Behavior in Response to Acute Exposure of Aqueous Copper Using Computer Assisted Video and Digital Image Analysis.

    PubMed

    Calfee, Robin D; Puglis, Holly J; Little, Edward E; Brumbaugh, William G; Mebane, Christopher A

    2016-01-01

    Behavioral responses of aquatic organisms to environmental contaminants can be precursors of other effects such as survival, growth, or reproduction. However, these responses may be subtle, and measurement can be challenging. Using juvenile white sturgeon (Acipenser transmontanus) with copper exposures, this paper illustrates techniques used for quantifying behavioral responses using computer assisted video and digital image analysis. In previous studies severe impairments in swimming behavior were observed among early life stage white sturgeon during acute and chronic exposures to copper. Sturgeon behavior was rapidly impaired and to the extent that survival in the field would be jeopardized, as fish would be swept downstream, or readily captured by predators. The objectives of this investigation were to illustrate protocols to quantify swimming activity during a series of acute copper exposures to determine time to effect during early lifestage development, and to understand the significance of these responses relative to survival of these vulnerable early lifestage fish. With mortality being on a time continuum, determining when copper first affects swimming ability helps us to understand the implications for population level effects. The techniques used are readily adaptable to experimental designs with other organisms and stressors. PMID:26967350

  6. Quantifying fish swimming behavior in response to acute exposure of aqueous copper using computer assisted video and digital image analysis

    USGS Publications Warehouse

    Calfee, Robin D.; Puglis, Holly J.; Little, Edward E.; Brumbaugh, William G.; Mebane, Christopher A.

    2016-01-01

    Behavioral responses of aquatic organisms to environmental contaminants can be precursors of other effects such as survival, growth, or reproduction. However, these responses may be subtle, and measurement can be challenging. Using juvenile white sturgeon (Acipenser transmontanus) with copper exposures, this paper illustrates techniques used for quantifying behavioral responses using computer assisted video and digital image analysis. In previous studies severe impairments in swimming behavior were observed among early life stage white sturgeon during acute and chronic exposures to copper. Sturgeon behavior was rapidly impaired and to the extent that survival in the field would be jeopardized, as fish would be swept downstream, or readily captured by predators. The objectives of this investigation were to illustrate protocols to quantify swimming activity during a series of acute copper exposures to determine time to effect during early lifestage development, and to understand the significance of these responses relative to survival of these vulnerable early lifestage fish. With mortality being on a time continuum, determining when copper first affects swimming ability helps us to understand the implications for population level effects. The techniques used are readily adaptable to experimental designs with other organisms and stressors.

  7. Quantifying Fish Swimming Behavior in Response to Acute Exposure of Aqueous Copper Using Computer Assisted Video and Digital Image Analysis

    PubMed Central

    Calfee, Robin D.; Puglis, Holly J.; Little, Edward E.; Brumbaugh, William G.; Mebane, Christopher A.

    2016-01-01

    Behavioral responses of aquatic organisms to environmental contaminants can be precursors of other effects such as survival, growth, or reproduction. However, these responses may be subtle, and measurement can be challenging. Using juvenile white sturgeon (Acipenser transmontanus) with copper exposures, this paper illustrates techniques used for quantifying behavioral responses using computer assisted video and digital image analysis. In previous studies severe impairments in swimming behavior were observed among early life stage white sturgeon during acute and chronic exposures to copper. Sturgeon behavior was rapidly impaired and to the extent that survival in the field would be jeopardized, as fish would be swept downstream, or readily captured by predators. The objectives of this investigation were to illustrate protocols to quantify swimming activity during a series of acute copper exposures to determine time to effect during early lifestage development, and to understand the significance of these responses relative to survival of these vulnerable early lifestage fish. With mortality being on a time continuum, determining when copper first affects swimming ability helps us to understand the implications for population level effects. The techniques used are readily adaptable to experimental designs with other organisms and stressors. PMID:26967350

  8. Impacts of stage-specific acute pesticide exposure on predicted population structure of the soft-shell clam, Mya arenaria.

    PubMed

    Lindsay, S; Chasse, J; Butler, R A; Morrill, W; Van Beneden, R J

    2010-07-01

    A combined laboratory and modeling approach was used to assess the impact of selected pesticides on early life stages of the soft-shell clam, Mya arenaria. Clams were exposed for 24h as veligers or pediveligers to the broad-spectrum herbicide hexazinone [3-cyclohexyl-6-(dimethylamino)-1-methyl-1,3,5-triazine-2,4(1h,3h)-dione; Velpar], the phenoxyacetic acid herbicide, 2,4-D (2,4-dichlorophenoxyacetic acid; Agway Super BK 32), or phosmet (Imidan). In addition, juvenile clams were exposed for 24h to 2,4-D and their growth monitored for 21 months. Laboratory experiments indicated veligers were more sensitive to acute pesticide exposure than pediveligers, with 2,4-D exposed veligers exhibiting the lowest survival among all treatments. Relative to controls, juvenile clams exposed to 0.5 ppm 2,4-D had enhanced survival following the initial 3 months of grow out. Juveniles exposed to 0.5, 5 and 10 ppm 2,4-D showed an initial growth delay relative to control clams, but at 21 months post-exposure these clams were significantly larger than control clams. Data from the larval and juvenile exposures were used to generate a stage-specific matrix model to predict the effect of pesticide exposure on clam populations. Impacts on simulated clam populations varied with the pesticide and stage exposed. For example, 2,4-D exposure of veligers and pediveligers significantly reduced predicted recruitment as well as population growth rate compared to controls, but juvenile exposure to 2,4-D did not significantly reduce population growth rate. With the exception of veligers exposed to 10 ppm, hexazinone exposure at the both veliger and pediveliger stages significantly reduced predicted recruitment success compared to 0 ppm controls. Hexazinone exposure also reduced modeled population growth rates, but these reductions were only slight in the pediveliger exposure simulations. Veliger and pediveliger exposure to phosmet reduced modeled population growth rate in a dose-dependent fashion

  9. Impacts of stage-specific acute pesticide exposure on predicted population structure of the soft-shell clam, Mya arenaria

    PubMed Central

    Lindsay, S.; Chasse, J.; Butler, R.A.; Morrill, W.; Van Beneden, R.J.

    2010-01-01

    A combined laboratory and modeling approach was used to assess the impact of selected pesticides on early life stages of the soft-shell clam, Mya arenaria. Clams were exposed for 24 h as veligers or pediveligers to the broad-spectrum herbicide hexazinone [3-cyclohexyl-6-(dimethylamino)-1-methyl-1,3,5-triazine-2,4 (1h,3h)-dione; (Velpar®)], the phenoxyacetic acid herbicide, 2,4-D (2,4- dichlorophenoxyacetic acid; Agway® Super BK 32), or phosmet (Imidan®). In addition, juvenile clams were exposed for 24 h to 2,4-D and their growth monitored for 21 months. Laboratory experiments indicated veligers were more sensitive to acute pesticide exposure than pediveligers, with 2,4-D exposed veligers exhibiting the lowest survival among all treatments. Relative to controls, juvenile clams exposed to 0.5 ppm 2,4-D had enhanced survival following the initial 3 months of grow out. Juveniles exposed to 0.5 ppm, 5 ppm and 10 ppm 2,4-D showed an initial growth delay relative to control clams, but at 21 months post exposure these clams were significantly larger than control clams. Data from the larval and juvenile exposures were used to generate a stage-specific matrix model to predict the effect of pesticide exposure on clam populations. Impacts on simulated clam populations varied with the pesticide and stage exposed. For example, 2,4-D exposure of veligers and pediveligers significantly reduced predicted recruitment as well as population growth rate compared to controls, but juvenile exposure to 2,4-D did not significantly reduce population growth rate. With the exception of veligers exposed to 10 ppm, hexazinone exposure at the both veliger and pediveliger stages significantly reduced predicted recruitment success compared to 0 ppm controls. Hexazinone exposure also reduced modeled population growth rates, but these reductions were only slight in the pediveliger exposure simulations. Veliger and pediveliger exposure to phosmet reduced modeled population growth rate in a dose

  10. Acute exposure to gas-supersaturated water does not affect reproductive success of female adult chinook salmon late in maturation

    USGS Publications Warehouse

    Gale, William L.; Maule, A.G.; Postera, A.; Peters, M.H.

    2004-01-01

    At times, total dissolved gas concentrations in the Columbia and Snake rivers have been elevated due to involuntary spill from high spring runoff and voluntary spill used as a method to pass juvenile salmonids over dams. The goal of this project was to determine if acute exposure to total dissolved gas supersaturation (TDGS) affects the reproductive performance of female chinook salmon late in their maturation. During this study, adult female spring chinook salmon were exposed to mean TDGS levels of 114.1 % to 125.5%. We ended exposures at first mortality, or at the appearance of impending death. Based on this criterion, exposures lasted from 10 to 68 h and were inversely related to TDGS. There was no effect of TDGS on pre-spawning mortality or fecundity when comparing treatment fish to experimental controls or the general hatchery population four to six weeks after exposures. Egg quality, based on egg weight and egg diameter, did not differ between treatment and control fish. Fertilization rate and survival to eyed-stage was high (>94%) for all groups. With the exception of Renibacterium salmoninarum (the causative agent of bacterial kidney disease; BKD), no viral or bacterial fish pathogens were isolated from experimental fish. The prevalence (about 45%) and severity of R. salmoninarum did not differ among the groups or the general hatchery population. We conclude that these acute exposures to moderate levels of gas-supersaturated water-perhaps similar to that experienced by immigrating adult salmon as they approach and pass a hydropower dam on the Columbia River-did not affect reproductive success of female chinook salmon late in their maturation. These results are most applicable to summer and fall chinook salmon, which migrate in the summer/fall and spawn shortly after reaching their natal streams. Published in 2004 by John Wiley and Sons, Ltd.

  11. Effect of repetitive acute cold exposures during the last phase of broiler embryogenesis on cold resistance through the life span.

    PubMed

    Shinder, D; Rusal, M; Giloh, M; Yahav, S

    2009-03-01

    The time just before hatch is critical, because the embryo shifts toward internal and external pipping. This study aimed to determine the beneficial effect of repeated acute reductions of the incubation temperature during the last phase of broiler embryogenesis on posthatch cold tolerance and on the development of ascites syndrome. Fertile eggs were incubated at 37.8 degrees C and 56% RH. At 18 and 19 d of incubation, 3 treatments were conducted, comprising 2 or 3 exposures to 15 degrees C for 30 or 60 min each. During these cold exposures, egg temperature was measured by infrared thermography to determine sensible heat loss from the eggs. At hatch, BW and body temperature were measured. At 3 and 14 d of age, chicks were challenged by cold exposure to 10 degrees C for 3 h. From 14 d of age onward, three-quarters of the chicks were raised under ascites-inducing conditions (AIC) and the others were raised under regular conditions. The sensible heat loss from the eggs was 512 +/- 66 cal and 718 +/- 126 cal for 30 and 60 min of cold exposure, respectively. No effect of treatment on hatchability was observed, but body temperature and BW were greater to significantly greater in the treated chicks. Cold challenges at 3 and 14 d of age revealed a relative thermoregulatory advantage of embryos exposed to cold for 60 min. Under AIC, fewer treated chickens than controls developed ascites. At 38 d of age, BW and relative breast muscle weight were numerically to significantly greater in the treated chicks than in the control chicks when both were raised under regular conditions, whereas no differences were observed among the chicks raised under AIC. Repeated brief acute cold exposures during the last phase of embryogenesis appeared to improve the ability of growing broilers to withstand low ambient temperatures during their life span. Moreover, chickens treated during embryogenesis improved their performance under regular growth conditions. PMID:19211536

  12. Single-exposure super-resolved interferometric microscopy by RGB multiplexing in lensless configuration

    NASA Astrophysics Data System (ADS)

    Granero, Luis; Ferreira, Carlos; Zalevsky, Zeev; García, Javier; Micó, Vicente

    2016-07-01

    Single-Exposure Super-Resolved Interferometric Microscopy (SESRIM) reports on a way to achieve one-dimensional (1-D) superresolved imaging in digital holographic microscopy (DHM) by a single illumination shot and digital recording. SESRIM provides color-coded angular multiplexing of the accessible sample's range of spatial frequencies and it allows their recording in a single CCD (color or monochrome) snapshot by adding 3 RGB coherent reference beams at the output plane. In this manuscript, we extend the applicability of SESRIM to the field of digital in-line holographic microscopy (DIHM), that is, working without lenses. As consequence of the in-line configuration, an additional restriction concerning the object field of view (FOV) must be imposed to the technique. Experimental results are reported for both a synthetic object (USAF resolution test target) and a biological sample (swine sperm sample) validating this new kind of superresolution imaging method named as lensless SESRIM (L-SESRIM).

  13. Acute exposure to waterpipe tobacco smoke induces changes in the oxidative and inflammatory markers in mouse lung

    PubMed Central

    Khabour, Omar F.; Alzoubi, Karem H.; Bani-Ahmad, Mohammed; Dodin, Arwa; Eissenberg, Thomas; Shihadeh, Alan

    2013-01-01

    Context Tobacco smoking represents a global public health threat, claiming approximately 5 million lives a year. Waterpipe tobacco use has become popular particularly among youth in the past decade, buttressed by the perception that the waterpipe “filters” the smoke, rendering it less harmful than cigarette smoke. Objective In this study, we examined the acute exposure of waterpipe smoking on lung inflammation and oxidative stress in mice, and compared that to cigarette smoking. Materials and methods Mice were divided into three groups; fresh air control, cigarette and waterpipe. Animals were exposed to fresh air, cigarette, or waterpipe smoke using whole body exposure system one hour daily for 7 days. Results Both cigarette and waterpipe smoke exposure resulted in elevation of total white blood cell count, as well as absolute count of neutrophils, macrophages, and lymphocytes (P < 0.01). Both exposures also elevated proinflammatory markers such as TNF-α and IL-6 in BALF (P < 0.05), and oxidative stress markers including GPx activity in lungs (P < 0.05). Moreover, waterpipe smoke increased catalase activity in the lung (P < 0.05). However, none of the treatments altered IL-10 levels. Discussion and conclusion Results of cigarette smoking confirmed previous finding. Waterpipe results indicate that, similar to cigarettes, exposure to waterpipe tobacco smoke is harmful to the lungs. PMID:22906173

  14. The Effects of Acute Waterborne Exposure to Sublethal Concentrations of Molybdenum on the Stress Response in Rainbow Trout, Oncorhynchus mykiss

    PubMed Central

    Ricketts, Chelsea D.; Bates, William R.; Reid, Scott D.

    2015-01-01

    To determine if molybdenum (Mo) is a chemical stressor, fingerling and juvenile rainbow trout (Oncorhynchus mykiss) were exposed to waterborne sodium molybdate (0, 2, 20, or 1,000 mg l-1 of Mo) and components of the physiological (plasma cortisol, blood glucose, and hematocrit) and cellular (heat shock protein [hsp] 72, hsp73, and hsp90 in the liver, gills, heart, and erythrocytes and metallothionein [MT] in the liver and gills) stress responses were measured prior to initiation of exposure and at 8, 24, and 96 h. During the acute exposure, plasma cortisol, blood glucose, and hematocrit levels remained unchanged in all treatments. Heat shock protein 72 was not induced as a result of exposure and there were no detectable changes in total hsp70 (72 and 73), hsp90, and MT levels in any of the tissues relative to controls. Both fingerling and juvenile fish responded with similar lack of apparent sensitivity to Mo exposure. These experiments demonstrate that exposure to waterborne Mo of up to 1,000 mg l-1 did not activate a physiological or cellular stress response in fish. Information from this study suggests that Mo water quality guidelines for the protection of aquatic life are highly protective of freshwater fish, namely rainbow trout. PMID:25629693

  15. Acute chlorine gas exposure produces transient inflammation and a progressive alteration in surfactant composition with accompanying mechanical dysfunction

    SciTech Connect

    Massa, Christopher B.; Scott, Pamela; Abramova, Elena; Gardner, Carol; Laskin, Debra L.; Gow, Andrew J.

    2014-07-01

    Acute Cl{sub 2} exposure following industrial accidents or military/terrorist activity causes pulmonary injury and severe acute respiratory distress. Prior studies suggest that antioxidant depletion is important in producing dysfunction, however a pathophysiologic mechanism has not been elucidated. We propose that acute Cl{sub 2} inhalation leads to oxidative modification of lung lining fluid, producing surfactant inactivation, inflammation and mechanical respiratory dysfunction at the organ level. C57BL/6J mice underwent whole-body exposure to an effective 60 ppm-hour Cl{sub 2} dose, and were euthanized 3, 24 and 48 h later. Whereas pulmonary architecture and endothelial barrier function were preserved, transient neutrophilia, peaking at 24 h, was noted. Increased expression of ARG1, CCL2, RETLNA, IL-1b, and PTGS2 genes was observed in bronchoalveolar lavage (BAL) cells with peak change in all genes at 24 h. Cl{sub 2} exposure had no effect on NOS2 mRNA or iNOS protein expression, nor on BAL NO{sub 3}{sup −} or NO{sub 2}{sup −}. Expression of the alternative macrophage activation markers, Relm-α and mannose receptor was increased in alveolar macrophages and pulmonary epithelium. Capillary surfactometry demonstrated impaired surfactant function, and altered BAL phospholipid and surfactant protein content following exposure. Organ level respiratory function was assessed by forced oscillation technique at 5 end expiratory pressures. Cl{sub 2} exposure had no significant effect on either airway or tissue resistance. Pulmonary elastance was elevated with time following exposure and demonstrated PEEP refractory derecruitment at 48 h, despite waning inflammation. These data support a role for surfactant inactivation as a physiologic mechanism underlying respiratory dysfunction following Cl{sub 2} inhalation. - Highlights: • Effect of 60 ppm*hr Cl{sub 2} gas on lung inflammation and mechanical function examined. • Pulmonary inflammation is transient and minor.

  16. Quantitative Structure--Activity Relationship Modeling of Rat Acute Toxicity by Oral Exposure

    EPA Science Inventory

    Background: Few Quantitative Structure-Activity Relationship (QSAR) studies have successfully modeled large, diverse rodent toxicity endpoints. Objective: In this study, a combinatorial QSAR approach has been employed for the creation of robust and predictive models of acute toxi...

  17. Short-term exposure to ambient particulate matter and emergency ambulance dispatch for acute illness in Japan.

    PubMed

    Tasmin, Saira; Ueda, Kayo; Stickley, Andrew; Yasumoto, Shinya; Phung, Vera Ling Hui; Oishi, Mizuki; Yasukouchi, Shusuke; Uehara, Yamato; Michikawa, Takehiro; Nitta, Hiroshi

    2016-10-01

    Short-term exposure to air pollution may be linked to negative health outcomes that require an emergency medical response. However, few studies have been undertaken on this phenomenon to date. The aim of this study therefore was to examine the association between short-term exposure to ambient suspended particulate matter (SPM) and emergency ambulance dispatches (EADs) for acute illness in Japan. Daily EAD data, daily mean SPM and meteorological data were obtained for four prefectures in the Kanto region of Japan for the period from 2007 to 2011. The area-specific association between daily EAD for acute illness and SPM was explored using generalized linear models while controlling for ambient temperature, relative humidity, seasonality, long-term trends, day of the week and public holidays. Stratified analyses were conducted to evaluate the modifying effects of age, sex and medical conditions. Area-specific estimates were combined using meta-analyses. For the total study period the mean level of SPM was 23.7μg/m(3). In general, higher SPM was associated with a significant increase in EAD for acute illness [estimated pooled relative risk (RR): 1.008, 95% CI: 1.007 to 1.010 per 10μg/m(3) increase in SPM at lag 0-1]. The effects of SPM on EAD for acute illness were significantly greater for moderate/mild medical conditions (e.g. cases that resulted in <3weeks hospitalization or no hospitalization) when compared to severe medical conditions (e.g. critical cases, and cases that led to >3weeks hospitalization or which resulted in death). Using EAD data, this study has shown the adverse health effects of ambient air pollution. This highlights the importance of reducing the level of air pollution in order to maintain population health and well-being. PMID:27235903

  18. Evaluation of Pulmonary and Systemic Toxicity of Oil Dispersant (COREXIT EC9500A®) Following Acute Repeated Inhalation Exposure

    PubMed Central

    Roberts, Jenny R; Anderson, Stacey E; Kan, Hong; Krajnak, Kristine; Thompson, Janet A; Kenyon, Allison; Goldsmith, William T; McKinney, Walter; Frazer, David G; Jackson, Mark; Fedan, Jeffrey S

    2014-01-01

    INTRODUCTION Oil spill cleanup workers come into contact with numerous potentially hazardous chemicals derived from the oil spills, as well as chemicals applied for mitigation of the spill, including oil dispersants. In response to the Deepwater Horizon Macondo well oil spill in the Gulf of Mexico in 2010, a record volume of the oil dispersant, COREXIT EC9500A, was delivered via aerial applications, raising concern regarding potential health effects that may result from pulmonary exposure to the dispersant. METHODS The current study examined the effects on pulmonary functions, cardiovascular functions, and systemic immune responses in rats to acute repeated inhalation exposure of COREXIT EC9500A at 25 mg/m3, five hours per day, over nine work days, or filtered air (control). At one and seven days following the last exposure, a battery of parameters was measured to evaluate lung function, injury, and inflammation; cardiovascular function; peripheral vascular responses; and systemic immune responses. RESULTS No significant alterations in airway reactivity were observed at one or seven days after exposure either in baseline values or following methacholine (MCh) inhalation challenge. Although there was a trend for an increase in lung neutrophils and phagocyte oxidant production at one-day post exposure, there were no significant differences in parameters of lung inflammation. In addition, increased blood monocytes and neutrophils, and decreased lymphocyte numbers at one-day post exposure also did not differ significantly from air controls, and no alterations in splenocyte populations, or serum or spleen immunoglobulin M (IgM) to antigen were observed. There were no significant differences in peripheral vascular responsiveness to vasoconstrictor and vasodilator agonists or in blood pressure (BP) responses to these agents; however, the baseline heart rate (HR) and HR responses to isoproterenol (ISO) were significantly elevated at one-day post exposure, with resolution

  19. An Adaptation of Prolonged Exposure Therapy for Pediatric Single Incident Trauma: A Case Series

    PubMed Central

    Adler Nevo, Gili; Manassis, Katharina

    2011-01-01

    Objective: To assess the efficacy of a modification for Prolonged Exposure (PE) therapy for single incident trauma in youth and examine the effective component(s) of treatment. Method: Fifteen youth (2 boys, 13 girls; mean age= 10.8 years) were treated with a developmentally modified version of PE called Trauma Mastery Therapy (TMT). The youth were evaluated pre-treatment, every 2 treatment sessions, and at 1 month follow-up. Primary outcome measure: the Child PTSD Symptom Scale (CPSS), a self administered PTSD questionnaire. Results: Post-treatment, 13 participants did not meet criteria for PTSD. Patients showed significant improvement at post-treatment. Analysis of variance models with pair-wise contrasts showed significantly higher scores at initiation of treatment as compared to the end of the exposure phase and, to a lesser extent, as compared to the psychoeducational phase, but no further significant improvement following the relapse prevention or follow-up phases. Conclusions: TMT appears to be a promising treatment for single incident trauma in youth. Flexibility within the structure of TMT may facilitate treatment success. The study suggests exposure, and to some extent, psychoeducation, to be important components of treatment. Additional research is required to further validate these initial findings. PMID:21541102

  20. Acute stress, depression, and anxiety symptoms among English and Spanish speaking children with recent trauma exposure

    PubMed Central

    Barber, Beth A.; Kohl, Krista L.; Kassam-Adams, Nancy; Gold, Jeffrey I.

    2015-01-01

    A growing literature suggests the clinical importance of acute stress disorder (ASD) symptoms in youth following potentially traumatic events. A multisite sample of English and Spanish speaking children and adolescents (N=479) between the ages of 8 to 17, along with their caregivers completed interviews and self-report questionnaires between 2 days and one month following the event. The results indicate that children with greater total acute stress symptoms reported greater depressive (r = .41, p < .01), and anxiety symptoms (r = .53, p < .01). Examining specific acute stress subscales, re-experiencing was correlated with anxiety (r = .47, p < .01) and arousal was correlated with depression (r = .50, p < .01) and anxiety (r = .55, p < .01). Age was inversely associated with total acute stress symptoms (r = -.24, p < .01), re-experiencing (r = -.17, p < .01), avoidance (r = -.27, p < .01), and arousal (r = -.19, p < .01) and gender was related to total anxiety symptoms (Spearman's rho = .17, p < .01). The current study supports the importance of screening acute stress symptoms and other mental health outcomes following a potentially traumatic event in children and adolescents. Early screening may enable clinicians to identify and acutely intervene to support children's psychological and physical recovery. PMID:24337685

  1. Formaldehyde Exposure and Mortality Risks From Acute Myeloid Leukemia and Other Lymphohematopoietic Malignancies in the US National Cancer Institute Cohort Study of Workers in Formaldehyde Industries

    PubMed Central

    Dell, Linda D.; Boffetta, Paolo; Gallagher, Alexa E.; Crawford, Lori; Lees, Peter SJ.; Mundt, Kenneth A.

    2015-01-01

    Objectives: To evaluate associations between cumulative and peak formaldehyde exposure and mortality from acute myeloid leukemia (AML) and other lymphohematopoietic malignancies. Methods: Cox proportional hazards analyses. Results: Acute myeloid leukemia was unrelated to cumulative exposure. Hodgkin lymphoma relative risk estimates in the highest exposure categories of cumulative and peak exposures were, respectively, 3.76 (Ptrend = 0.05) and 5.13 (Ptrend = 0.003). There were suggestive associations with peak exposure observed for chronic myeloid leukemia, albeit based on very small numbers. No other lymphohematopoietic malignancy was associated with either chronic or peak exposure. Conclusions: Insofar as there is no prior epidemiologic evidence supporting associations between formaldehyde and either Hodgkin leukemia or chronic myeloid leukemia, any causal interpretations of the observed risk patterns are at most tentative. Findings from this re-analysis do not support the hypothesis that formaldehyde is a cause of AML. PMID:26147546

  2. Single exposure simultaneous acquisition of digital and conventional radiographs utilizing unaltered dose.

    PubMed

    Oestmann, J W; Greene, R

    1988-11-01

    We describe the simultaneous acquisition of digital and conventional radiographs with a single standard radiographic exposure. A digitizable storage phosphor (ST Imaging Plate, FujiTM) is sandwiched into a radiographic cassette (X-Omatic, KodakTM) behind a conventional radiographic film-screen combination (Lanex medium screens, OC film, KodakTM). The barium fluorohalide storage phosphor is digitized with a helium-neon laser scanner (TCR 201, ToshibaTM), and the conventional radiograph is processed in the standard fashion (M7B, KodakTM). The storage phosphor is exposed by the "wasted" radiation normally exiting the back of the film-screen combination (32% of the cassette entrance dose at 141 kVp). At a standard exposure (6.3 mAs), the conventional radiograph is of unaltered quality, and the digital image appears to have an adequate signal-to-noise ratio for chest studies despite the lower exposure dose. This technique produces twin images of identical spatial and temporal registration and avoids the added radiation exposure normally required to carry out comparative studies. PMID:3234405

  3. Adolescent mice are less sensitive to the effects of acute nicotine on context pre-exposure than adults.

    PubMed

    Kutlu, Munir Gunes; Braak, David C; Tumolo, Jessica M; Gould, Thomas J

    2016-07-01

    Adolescence is a critical developmental period associated with both increased vulnerability to substance abuse and maturation of certain brain regions important for learning and memory such as the hippocampus. In this study, we employed a hippocampus-dependent learning context pre-exposure facilitation effect (CPFE) paradigm in order to test the effects of acute nicotine on contextual processing during adolescence (post-natal day (PND) 38) and adulthood (PND 53). In Experiment 1, adolescent or adult C57BL6/J mice received either saline or one of three nicotine doses (0.09, 0.18, and 0.36mg/kg) prior to contextual pre-exposure and testing. Our results demonstrated that both adolescent and adult mice showed CPFE in the saline groups. However, adolescent mice only showed acute nicotine enhancement of CPFE with the highest nicotine dose whereas adult mice showed the enhancing effects of acute nicotine with all three doses. In Experiment 2, to determine if the lack of nicotine's effects on CPFE shown by adolescent mice is specific to the age when they are tested, mice were either given contextual pre-exposure during adolescence or adulthood and received immediate shock and testing during adulthood after a 15day delay. We found that both adolescent and adult mice showed CPFE in the saline groups when tested during adulthood. However, like Experiment 1, mice that received contextual pre-exposure during adolescence did not show acute nicotine enhancement except at the highest dose (0.36mg/kg) whereas both low (0.09mg/kg) and high (0.36mg/kg) doses enhanced CPFE in adult mice. Finally, we showed that the enhanced freezing response found with 0.36mg/kg nicotine in the 15-day experiment may be a result of decreased locomotor activity as mice that received this dose of nicotine traveled shorter distances in an open field paradigm. Overall, our results indicate that while adolescent mice showed normal contextual processing when tested both during adolescence and adulthood, they

  4. Acute and sublethal effects of sequential exposure to the pesticide azinphos-methyl on juvenile earthworms (Eisenia andrei).

    PubMed

    Jordaan, Martine S; Reinecke, Sophié A; Reinecke, Adriaan J

    2012-04-01

    The use of organophosphate pesticides is an integral part of commercial farming activities and these substances have been implicated as a major source of environmental contamination and may impact on a range of non-target fauna. The extent to which soil dwelling non-target organisms are affected by exposure to the organophosphate azinphos-methyl was investigated through monitoring selected biomarker responses and life cycle effects under laboratory conditions in the earthworm Eisenia andrei. Standard acute toxicity tests were conducted followed by a sequential exposure regime experiment, in order to assess the effects of multiple pesticide applications on biomarker (cholinesterase activity and neutral red retention time), life-cycle (growth and reproduction) and behaviour (avoidance and burrowing activity) responses. The present study indicates that the time between exposure events was a more important variable than concentration and that a longer interval between exposures may mitigate the effects of pesticide exposure provided that the exposure concentration is low. Additionally, it was shown that E. andrei was unable to avoid the presence of azinphos-methyl in soil, even at concentrations as high as 50% of the LC(50) value, indicating that the presence of azinphos-methyl in the soil pose a realistic threat to earthworms and other soil dwelling organisms. The ChE inhibition test showed a high percentage inhibition of the enzyme in all exposure groups that survived and NRR times of exposed organisms were lower than that of the controls. The present study yielded important results that contribute to the understanding of biological impacts of pesticide pollution on the environment. Extrapolating these results can aid in optimising pesticide application regimes to mitigate the environmental effects thereof and thus ensuring sustained soil biodiversity in agricultural areas. PMID:22086221

  5. Single dose oral ketoprofen and dexketoprofen for acute postoperative pain in adults

    PubMed Central

    Barden, Jodie; Derry, Sheena; McQuay, Henry J; Moore, R Andrew

    2014-01-01

    Background Ketoprofen is a non-selective non-steroidal anti-inflammatory drug (NSAID) used to treat acute and chronic painful conditions. Dexketoprofen is the (S)-enantiomer, which is believed to confer analgesia. Theoretically dexketoprofen is expected to provide equivalent analgesia to ketoprofen at half the dose, with a consequent reduction in gastrointestinal adverse events. Objectives To assess efficacy, duration of action, and associated adverse events of single dose oral ketoprofen and dexketoprofen in acute postoperative pain in adults. Search methods We searched Cochrane CENTRAL, MEDLINE, EMBASE and the Oxford Pain Relief Database for studies to August 2009. Selection criteria Randomised, double blind, placebo-controlled trials of single dose orally administered ketoprofen and dexketoprofen in adults with moderate to severe acute postoperative pain. Data collection and analysis Two review authors independently assessed trial quality and extracted data. Pain relief or pain intensity data were extracted and converted into the dichotomous outcome of number of participants with at least 50% pain relief over 4 to 6 hours, from which relative risk and number-needed-to-treat-to-benefit (NNT) were calculated. Numbers of participants using rescue medication over specified time periods, and time to use of rescue medication, were sought as additional measures of efficacy. Information on adverse events and withdrawals was collected. Main results Fourteen studies compared ketoprofen (968 participants) at mainly 25 mg and 50 mg with placebo (520 participants). Seven studies compared dexketoprofen (681 participants) at mainly 10 mg to 25 mg with placebo (289 participants). Studies were of adequate reporting quality, and participants had pain following dental, orthopaedic, obstetric, gynaecological and general surgery. There was considerable clinical heterogeneity between studies in dental and other types of surgery, particularly bunionectomy, which limited analysis

  6. Dose-additivity modeling for acute and repeated exposure to a mixture of N-methycarbamate Pesticides

    EPA Science Inventory

    The toxicity of N-methylcarbamate pesticides is attributed to the reversible inhibition of cholinesterase (ChE) enzymes in the central and peripheral nervous system. The inhibition of ChE following a single exposure to this class of pesticides has been modeled using a dose-additi...

  7. Charge trapping in aligned single-walled carbon nanotube arrays induced by ionizing radiation exposure

    SciTech Connect

    Esqueda, Ivan S.; Cress, Cory D.; Che, Yuchi; Cao, Yu; Zhou, Chongwu

    2014-02-07

    The effects of near-interfacial trapping induced by ionizing radiation exposure of aligned single-walled carbon nanotube (SWCNT) arrays are investigated via measurements of gate hysteresis in the transfer characteristics of aligned SWCNT field-effect transistors. Gate hysteresis is attributed to charge injection (i.e., trapping) from the SWCNTs into radiation-induced traps in regions near the SWCNT/dielectric interface. Self-consistent calculations of surface-potential, carrier density, and trapped charge are used to describe hysteresis as a function of ionizing radiation exposure. Hysteresis width (h) and its dependence on gate sweep range are investigated analytically. The effects of non-uniform trap energy distributions on the relationship between hysteresis, gate sweep range, and total ionizing dose are demonstrated with simulations and verified experimentally.

  8. Acute exposure to a sublethal dose of imidacloprid and coumaphos enhances olfactory learning and memory in the honeybee Apis mellifera.

    PubMed

    Williamson, Sally M; Baker, Daniel D; Wright, Geraldine A

    2013-06-01

    The decline of honeybees and other pollinating insects is a current cause for concern. A major factor implicated in their decline is exposure to agricultural chemicals, in particular the neonicotinoid insecticides such as imidacloprid. Honeybees are also subjected to additional chemical exposure when beekeepers treat hives with acaricides to combat the mite Varroa destructor. Here, we assess the effects of acute sublethal doses of the neonicotinoid imidacloprid, and the organophosphate acaricide coumaphos, on honey bee learning and memory. Imidacloprid had little effect on performance in a six-trial olfactory conditioning assay, while coumaphos caused a modest impairment. We report a surprising lack of additive adverse effects when both compounds were administered simultaneously, which instead produced a modest improvement in learning and memory. PMID:23160709

  9. Assessing chronic fish health: An application to a case of an acute exposure to chemically treated crude oil.

    PubMed

    Mauduit, F; Domenici, P; Farrell, A P; Lacroix, C; Le Floch, S; Lemaire, P; Nicolas-Kopec, A; Whittington, M; Zambonino-Infante, J L; Claireaux, G

    2016-09-01

    Human alteration of marine ecosystems is substantial and growing. Yet, no adequate methodology exists that provides reliable predictions of how environmental degradation will affect these ecosystems at a relevant level of biological organization. The primary objective of this study was to develop a methodology to evaluate a fish's capacity to face a well-established environmental challenge, an exposure to chemically dispersed oil, and characterize the long-term consequences. Therefore, we applied high-throughput, non-lethal challenge tests to assess hypoxia tolerance, temperature susceptibility and maximal swimming speed as proxies for a fish's functional integrity. These whole animal challenge tests were implemented before (1 month) and after (1 month) juvenile European sea bass (Dicentrarchus labrax) had been acutely exposed (48h) to a mixture containing 0.08gL(-1) of weathered Arabian light crude oil plus 4% dispersant (Corexit© EC9500A), a realistic exposure concentration during an oil spill. In addition, experimental populations were then transferred into semi-natural tidal mesocosm ponds and correlates of Darwinian fitness (growth and survival) were monitored over a period of 4 months. Our results revealed that fish acutely exposed to chemically dispersed oil remained impaired in terms of their hypoxia tolerance and swimming performance, but not in temperature susceptibility for 1 month post-exposure. Nevertheless, these functional impairments had no subsequent ecological consequences under mildly selective environmental conditions since growth and survival were not impacted during the mesocosm pond study. Furthermore, the earlier effects on fish performance were presumably temporary because re-testing the fish 10 months post-exposure revealed no significant residual effects on hypoxia tolerance, temperature susceptibility and maximal swimming speed. We propose that the functional proxies and correlates of Darwinian fitness used here provide a useful

  10. The long-term effects of acute exposure to ionising radiation on survival and fertility in Daphnia magna.

    PubMed

    Sarapultseva, Elena I; Dubrova, Yuri E

    2016-10-01

    The results of recent studies have provided strong evidence for the transgenerational effects of parental exposure to ionising radiation and chemical mutagens. However, the transgenerational effects of parental exposure on survival and fertility remain poorly understood. To establish whether parental irradiation can affect the survival and fertility of directly exposed organisms and their offspring, crustacean Daphnia magna were given 10, 100, 1000 and 10,000mGy of acute γ-rays. Exposure to 1000 and 10,000mGy significantly compromised the viability of irradiated Daphnia and their first-generation progeny, but did not affect the second-generation progeny. The fertility of F0 and F1Daphnia gradually declined with the dose of parental exposure and significantly decreased at dose of 100mGy and at higher doses. The effects of parental irradiation on the number of broods were only observed among the F0Daphnia exposed to 1000 and 10,000mGy, whereas the brood size was equally affected in the two consecutive generations. In contrast, the F2 total fertility was compromised only among progeny of parents that received the highest dose of 10,000mGy. We propose that the decreased fertility observed among the F2 progeny of parents exposed to 10,000mGy is attributed to transgenerational effects of parental irradiation. Our results also indicate a substantial recovery of the F2 progeny of irradiated F0Daphnia exposed to the lower doses of acute γ-rays. PMID:27288911

  11. Quantification of Optic Disc Edema during Exposure to High Altitude Shows No Correlation to Acute Mountain Sickness

    PubMed Central

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

    2011-01-01

    Background The study aimed to quantify changes of the optic nerve head (ONH) during exposure to high altitude and to assess a correlation with acute mountain sickness (AMS). This work is related to the Tuebingen High Altitude Ophthalmology (THAO) study. Methodology/Principal Findings A confocal scanning laser ophthalmoscope (cSLO, Heidelberg Retina Tomograph, HRT3®) was used to quantify changes at the ONH in 18 healthy participants before, during and after rapid ascent to high altitude (4559 m). Slitlamp biomicroscopy was used for clinical optic disc evaluation; AMS was assessed with Lake Louise (LL) and AMS-cerebral (AMS-c) scores; oxygen saturation (SpO2) and heart rate (HR) were monitored. These parameters were used to correlate with changes at the ONH. After the first night spent at high altitude, incidence of AMS was 55% and presence of clinical optic disc edema (ODE) 79%. Key stereometric parameters of the HRT3® used to describe ODE (mean retinal nerve fiber layer [RNFL] thickness, RNFL cross sectional area, optic disc rim volume and maximum contour elevation) changed significantly at high altitude compared to baseline (p<0.05) and were consistent with clinically described ODE. All changes were reversible in all participants after descent. There was no significant correlation between parameters of ODE and AMS, SpO2 or HR. Conclusions/Significance Exposure to high altitude leads to reversible ODE in the majority of healthy subjects. However, these changes did not correlate with AMS or basic physiologic parameters such as SpO2 and HR. For the first time, a quantitative approach has been used to assess these changes during acute, non-acclimatized high altitude exposure. In conclusion, ODE presents a reaction of the body to high altitude exposure unrelated to AMS. PMID:22069483

  12. Electronic transport properties of pentacene single crystals upon exposure to air

    SciTech Connect

    Jurchescu, Oana D.; Baas, Jacob; Palstra, Thomas T.M.

    2005-08-01

    We report the effect of air exposure on the electronic properties of pentacene single crystals. Air can diffuse reversibly in and out of the crystals and influences the physical properties. We discern two competing mechanisms that modulate the electronic transport. The presence of oxygen increases the hole conduction, as in dark four O{sub 2} molecules introduce one charge carrier. This effect is enhanced by the presence of visible light. Contrarily, water, present in ambient air, is incorporated in the crystal lattice and forms trapping sites for injected charges.

  13. Electronic transport properties of pentacene single crystals upon exposure to air

    NASA Astrophysics Data System (ADS)

    Jurchescu, Oana D.; Baas, Jacob; Palstra, Thomas T. M.

    2005-08-01

    We report the effect of air exposure on the electronic properties of pentacene single crystals. Air can diffuse reversibly in and out of the crystals and influences the physical properties. We discern two competing mechanisms that modulate the electronic transport. The presence of oxygen increases the hole conduction, as in dark four O2 molecules introduce one charge carrier. This effect is enhanced by the presence of visible light. Contrarily, water, present in ambient air, is incorporated in the crystal lattice and forms trapping sites for injected charges.

  14. Moderate (2%, v/v) Ethanol Feeding Alters Hepatic Wound Healing after Acute Carbon Tetrachloride Exposure in Mice

    PubMed Central

    Deshpande, Krutika T.; Liu, Shinlan; McCracken, Jennifer M.; Jiang, Lu; Gaw, Ta Ehpaw; Kaydo, Lindsey N.; Richard, Zachary C.; O’Neil, Maura F.; Pritchard, Michele T.

    2016-01-01

    Wound healing consists of three overlapping phases: inflammation, proliferation, and matrix synthesis and remodeling. Prolonged alcohol abuse can cause liver fibrosis due to deregulated matrix remodeling. Previous studies demonstrated that moderate ethanol feeding enhances liver fibrogenic markers and frank fibrosis independent of differences in CCl4-induced liver injury. Our objective was to determine whether or not other phases of the hepatic wound healing response were affected by moderate ethanol after CCl4 exposure. Mice were fed moderate ethanol (2% v/v) for two days and then were exposed to CCl4 and euthanized 24–96 h later. Liver injury was not different between pair- and ethanol-fed mice; however, removal of necrotic tissue was delayed after CCl4-induced liver injury in ethanol-fed mice. Inflammation, measured by TNFα mRNA and protein and hepatic Ly6c transcript accumulation, was reduced and associated with enhanced hepatocyte apoptosis after ethanol feeding. Hepatocytes entered the cell cycle equivalently in pair- and ethanol-fed mice after CCl4 exposure, but hepatocyte proliferation was prolonged in livers from ethanol-fed mice. CCl4-induced hepatic stellate cell activation was increased and matrix remodeling was prolonged in ethanol-fed mice compared to controls. Taken together, moderate ethanol affected each phase of the wound healing response to CCl4. These data highlight previously unknown effects of moderate ethanol exposure on hepatic wound healing after acute hepatotoxicant exposure. PMID:26751492

  15. Acute effects of motor vehicle traffic-related air pollution exposures on measures of oxidative stress in human airways

    PubMed Central

    Laumbach, Robert J.; Kipen, Howard M.

    2014-01-01

    Epidemiological studies have linked exposure to traffic-related air pollutants to increased respiratory and cardiovascular morbidity and mortality. Evidence from human, animal, and in vitro studies supports an important role for oxidative stress in the pathophysiological pathways underlying the adverse health effects of air pollutants. In controlled-exposure studies of animals and humans, emissions from diesel engines, a major source of traffic-related air pollutants, cause pulmonary and systemic inflammation that is mediated by redox-sensitive signaling pathways. Assessment of human responses to traffic-related air pollution under realistic conditions is challenging due to the complex, dynamic nature of near-roadway exposure. Noninvasive measurement of biomarkers in breath and breath condensate may be particularly useful for evaluating the role of oxidative stress in acute responses to exposures that occur in vehicles or during near-roadway activities. Promising biomarkers include nitric oxide in exhaled breath, and nitrite/nitrate, malondialdehyde, and F2-isoprostanes in exhaled breath condensate. PMID:20716291

  16. Oxidative stress related to chlorpyrifos exposure in rainbow trout: Acute and medium term effects on genetic biomarkers.

    PubMed

    Benedetto, A; Brizio, P; Squadrone, S; Scanzio, T; Righetti, M; Gasco, L; Prearo, M; Abete, M C

    2016-05-01

    Organophosphates (OPs) are derivatives of phosphoric acid widely used in agriculture as pesticides. Chlorpyrifos (CPF) is an OP that is extremely toxic to aquatic organisms. Rainbow trout (Oncorhynchus mykiss) is considered as a sentinel model species for ecotoxicology assessment in freshwater ecosystems. An exposure study was carried out on rainbow trout to investigate genetic responses to CPF-induced oxidative stress by Real-Time PCR, and to determine the accumulation dynamics of CPF and toxic metabolite chlorpyrifos-oxon (CPF-ox) in edible parts, by HPLC-MS/MS. Among the genes considered to be related to oxidative stress, a significant increase in HSP70 mRNA levels was observed in liver samples up to 14 days after CPF exposure (0.05 mg/L). CPF concentrations in muscle samples reach mean values of 285.25 ng/g within 96 hours of exposure, while CPF-ox concentrations were always under the limit of quantification (LOQ) of the applied method. Our findings lead us to consider HSP70 as a suitable genetic marker in rainbow trout for acute and medium-term monitoring of CPF exposure, complementary to analytical determinations. PMID:27017883

  17. Single dose oral naproxen and naproxen sodium for acute postoperative pain (Review)

    PubMed Central

    Mason, L; Edwards, JE; Moore, RA; McQuay, HJ

    2014-01-01

    Background Postoperative pain is often poorly managed. Treatment options include a range of drug therapies such as non-steroidal anti-inflammatory drugs (NSAIDs) of which naproxen is one. Naproxen is used to treat a variety of painful conditions including acute postoperative pain, and is often combined with sodium to improve its solubility for oral administration. Naproxen sodium 550 mg (equivalent to 500 mg of naproxen) is considered to be an effective dose for treating postoperative pain but to date no systematic review of the effectiveness of naproxen/naproxen sodium at different doses has been published. Objectives To assess the efficacy, safety and duration of action of a single oral dose of naproxen or naproxen sodium for acute postoperative pain in adults. Search strategy We searched The Cochrane Library, MEDLINE, EMBASE and the Oxford Pain Relief Database for relevant studies. Additional studies were identified from the reference list of retrieved reports. The most recent search was undertaken in July 2004. Selection criteria Included studies were randomised, double blind, placebo-controlled trials of a single dose of orally administered naproxen or naproxen sodium in adults with moderate to severe acute postoperative pain. Data collection and analysis Pain relief or pain intensity data were extracted and converted into dichotomous information to give the number of patients with at least 50% pain relief over four to six hours. Relative risk estimates (RR) and the number-needed-to-treat (NNT) for at least 50% pain relief were then calculated. Information was sought on the percentage of patients experiencing any adverse event, and the number-needed-to-harm was derived. Time to remedication was also estimated. Main results Ten trials (996 patients) met the inclusion criteria: nine assessed naproxen sodium; one combined the results from two small trials of naproxen alone. Included studies scored well for methodological quality. Meta-analysis of six trials (500

  18. Acute stress, depression, and anxiety symptoms among English and Spanish speaking children with recent trauma exposure.

    PubMed

    Barber, Beth A; Kohl, Krista L; Kassam-Adams, Nancy; Gold, Jeffrey I

    2014-03-01

    A growing literature suggests the clinical importance of acute stress disorder symptoms in youth following potentially traumatic events. A multisite sample of English and Spanish speaking children and adolescents (N = 479) between the ages of 8-17, along with their caregivers completed interviews and self-report questionnaires between 2 days and 1 month following the event. The results indicate that children with greater total acute stress symptoms reported greater depressive (r = .41, p < .01) and anxiety symptoms (r = .53, p < .01). Examining specific acute stress subscales, reexperiencing was correlated with anxiety (r = .47, p < .01) and arousal was correlated with depression (r = .50, p < .01) and anxiety (r = .55, p < .01). Age was inversely associated with total acute stress symptoms (r = -.24, p < .01), reexperiencing (r = -.17, p < .01), avoidance (r = -.27, p < .01), and arousal (r = -.19, p < .01) and gender was related to total anxiety symptoms (Spearman's ρ = .17, p < .01). The current study supports the importance of screening acute stress symptoms and other mental health outcomes following a potentially traumatic event in children and adolescents. Early screening may enable clinicians to identify and acutely intervene to support children's psychological and physical recovery. PMID:24337685

  19. Mechanical Revascularization for Acute Ischemic Stroke: A Single-Center, Retrospective Analysis

    SciTech Connect

    Jeromel, Miran Milosevic, Z. V. Kocijancic, I. J. Lovric, D.; Svigelj, V. Zvan, B.

    2013-04-15

    BackgroundEndovascular mechanical revascularization (thrombectomy) is an increasingly used method for intracranial large vessel recanalization in acute stroke. The purpose of the study was to analyze the recanalization rate, clinical outcome, and complication rate in our stroke patients treated with mechanical revascularization. A total of 57 patients with large vessel stroke (within 3 h for anterior and 12 h for posterior circulation) were treated with mechanical revascularization at a single center during 24 months. The primary goal of endovascular treatment using different mechanical devices was recanalization of the occluded vessel. Recanalization rate (reported as thrombolysis in cerebral infarction [TICI] score), clinical outcome (reported as National Institutes of Health Stroke Scale [NIHSS] score and modified Rankin scale [mRS] score), as well as periprocedural complications were analyzed. The mean age of the patients was 63.1 {+-} 12.9 years, with baseline median NIHSS score of 14 (interquartile range, 9.5-19). Successful recanalization (TICI 2b or 3) was achieved in 41 (72 %) patients. Twenty patients (35 %) presented with favorable outcome (mRS {<=}2) 30 days after stroke. Overall, significant neurological improvement ({>=}4 NIHSS point reduction) occurred in 36 (63 %) patients. A clinically significant procedure-related adverse events (vessel disruption, peri/postprocedural intracranial bleeding) defined with decline in NIHSS of {>=}4 or death occurred in three (5 %) patients. The study showed a high recanalization rate with improved clinical outcome and a low rate of periprocedural complications in our stroke patients treated with mechanical revascularization. Therefore, we could conclude that endovascular revascularization (primary or in combination with a bridging thrombolysis) was an effective and safe procedure for intracranial large vessel recanalization in acute stroke.

  20. Transfusion Related Acute Lung Injury (TRALI): A Single Institution Experience of 15 Years.

    PubMed

    Kumar, Ramesh; Sedky, Mohammed Jaber; Varghese, Sunny Joseph; Sharawy, Osama Ebrahim

    2016-09-01

    Transfusion related acute Lung injury (TRALI) though a serious blood transfusion reaction with a fatality rate of 5-25 % presents with acute respiratory distress with hypoxaemia and noncardiac pulmonary oedema within 6 h of transfusion. In non fatal cases, it may resolve within 72 h or earlier. Although reported with an incidence of 1:5000, its true occurrence is rather unknown. Pathogenesis is believed to be related to sequestration and adhesion of neutrophils to the pulmonary capillary endothelium and its activation leading to its destruction and leaks. The patient's underlying condition, anti-neutrophil antibody in the transfused donor plasma and certain lipids that accumulate in routinely stores blood and components are important in its aetiopathogenesis. Patient's predisposing conditions include haematological malignancy, major surgery (especially cardiac), trauma and infections. The more commonly incriminated products include fresh frozen plasma (FFP), platelets (whole blood derived and apheresis), whole blood and Packed RBC. Occasional cases involving cryoprecipitate and Intravenous immunoglobulin (IVig) have also been reported. We present a 15 year single institution experience of TRALI, during which we observed 9 cases among 170,871 transfusions, giving an incidence of 1:19,000. We did not encounter cases of haematological malignancy or cardiac surgery in our TRALI patients. Among the blood products, that could be related to TRALI in our patients included solitary cases receiving cryoprecipitate, IVIg, and recombinant Factor VII apart from platelets and FFP. All patients were treated with oxygen support. Six patients required mechanical ventilation. Off label hydrocortisone was given to all patients. There were no cases of fatality among our patients. PMID:27429525

  1. Measurement of various respiratory dynamics parameters following acute inhalational exposure to soman vapor in conscious rats.

    PubMed

    Perkins, Michael W; Wong, Benjamin; Rodriguez, Ashley; Devorak, Jennifer; Sciuto, Alfred M

    2015-01-01

    Respiratory dynamics were investigated in head-out plethysmography chambers following inhalational exposure to soman in untreated, non-anesthetized rats. A multipass saturator cell was used to generate 520, 560 and 600 mg × min/m(3) of soman vapor in a customized inhalational exposure system. Various respiratory dynamic parameters were collected from male Sprague-Dawley rats (300--350 g) during (20 min) and 24 h (10 min) after inhalational exposure. Signs of CWNA-induced cholinergic crisis were observed in all soman-exposed animals. Percentage body weight loss and lung edema were observed in all soman-exposed animals, with significant increases in both at 24 h following exposure to 600 mg × min/m(3). Exposure to soman resulted in increases in respiratory frequency (RF) in animals exposed to 560 and 600 mg × min/m(3) with significant increases following exposure to 560 mg × min/m(3) at 24 h. No significant alterations in inspiratory time (IT) or expiratory time (ET) were observed in soman-exposed animals 24 h post-exposure. Prominent increases in tidal volume (TV) and minute volume (MV) were observed at 24 h post-exposure in animals exposed to 600 mg × min/m(3). Peak inspiratory (PIF) and expiratory flow (PEF) followed similar patterns and increased 24 h post-exposure to 600 mg × min/m(3) of soman. Results demonstrate that inhalational exposure to 600 mg × min/m(3) soman produces notable alterations in various respiratory dynamic parameters at 24 h. The following multitude of physiological changes in respiratory dynamics highlights the need to develop countermeasures that protect against respiratory toxicity and lung injury. PMID:26207672

  2. Exposure and measurement contributions to estimates of acute air pollution effects.

    PubMed

    Sheppard, Lianne; Slaughter, James C; Schildcrout, Jonathan; Liu, L-J Sally; Lumley, Thomas

    2005-07-01

    Air pollution health effect studies are intended to estimate the effect of a pollutant on a health outcome. The definition of this effect depends upon the study design, disease model parameterization, and the type of analysis. Further limitations are imposed by the nature of exposure and our ability to measure it. We define a plausible exposure model for air pollutants that are relatively nonreactive and discuss how exposure varies. We discuss plausible disease models and show how their parameterizations are affected by different exposure partitions and by different study designs. We then discuss a measurement model conditional on ambient concentrations and incorporate this into the disease model. We use simulation studies to show the impact of a range of exposure model assumptions on estimation of the health effect in the ecologic time series design. This design only uses information from the time-varying ambient source exposure. When ambient and nonambient sources are independent, exposure variation due to nonambient source exposures behaves like Berkson measurement error and does not bias the effect estimates. Variation in the population attenuation of ambient concentrations over time does bias the estimates with the bias being either positive or negative depending upon the association of this parameter with ambient pollution. It is not realistic to substitute measured average personal exposures into time series studies because so much of the variation in personal exposures comes from nonambient sources that do not contribute information in the time series design. We conclude that general statements about the implications of measurement error need to be conditioned on the health effect study design and the health effect parameter to be estimated. PMID:15602584

  3. Human Airway Epithelial Cell Responses to Single Walled Carbon Nanotube Exposure: Nanorope-Residual Body Formation

    SciTech Connect

    Panessa-Warren, Barbara J.; Warren, John B.; Kisslinger, Kim; Crosson, Kenya; Maye, Mathew M.

    2012-11-01

    This investigation examines the 'first contact responses' of in vitro human epithelial airway cells exposed to unrefined single walled carbon nanotubes (SWCNTs) [containing metal catalyst, carbon black, amorphous carbon, graphitic shells, and SWCNTs], and refined acid/peroxide cleaned and cut SWCNTs at low and high dose exposures (0.16 ug/L and 1.60 ug/L) for 2, 3 and 3.5 hours. FTIR, X-ray compositional analysis, morphological TEM analysis and UV-Vis were used to physicochemically characterize the SWCNTs in this study. Following SWCNT exposure to human lung NCI-H292 epithelial monolayers, the airway cells were prepared for light microscopy vital staining, or fixed in glutaraldehyde for SEM/TEM imaging to determine SWCNT binding, uptake, intracellular processing and organellar/SWCNT fate within the exposure period. At 2 hr exposures to both unrefined Carbolex, and refined SWCNTs (at both high and low doses), there were no increases in lung cell necrosis compared to controls. However high dose, 3 hr exposures to unrefined Carbolex material produced severe cell damage (apical and basal plasma membrane holes, decreased mitochondria, numerous intracellular vesicles containing nanomaterial and membrane fragments) and increased cell necrosis. The refined SWCNTs exposed for 3 hr at low dose produced no increase in cell death, although high dose exposure produced significant cell death. By TEM, Acid/peroxide cleaned SWCNT 3 hr exposures at high and low doses, revealed SWCNTs attachment to cell surface mucin, and SWCNT uptake into the cells during membrane recycling. Membranes and SWCNTs were seen within cytoplasmic lamellar body-type vesicles, where vesicular contents were bio-degraded, eventually forming long SWCNT-nanoropes, which were subsequently released into the cytoplasm as clusters of attached nanoropes, as the vesicle membranes fragmented. These Nanorope-Residual Bodies did not cause damage to the surrounding organelles or cytoplasm, and seemed very stabile in the

  4. Large object investigation by digital holography with effective spectrum multiplexing under single-exposure approach

    SciTech Connect

    Liu, Ning Zhang, Yingying; Xie, Jun

    2014-10-13

    We present a method to investigate large object by digital holography with effective spectrum multiplexing under single-exposure approach. This method splits the original reference beam and redirects one of its branches as a second object beam. Through the modified Mach-Zehnder interferometer, the two object beams can illuminate different parts of the large object and create a spectrum multiplexed hologram onto the focal plane array of the charge-coupled device/complementary metal oxide semiconductor camera. After correct spectrum extraction and image reconstruction, the large object can be fully observed within only one single snap-shot. The flexibility and great performance make our method a very attractive and promising technique for large object investigation under common 632.8 nm illumination.

  5. Acute exposure to cold rapidly increases the number of nucleotide binding sites, but not proton conductance, in BAT mitochondria

    SciTech Connect

    Swick, A.G.; Swick, R.W.

    1986-03-01

    Studies on the effect of acute cold exposure of rats on brown adipose tissue (BAT) thermogenic activity have produced equivocal results. Therefore, the authors have reexamined the response of BAT mitochondria to abrupt changes in environmental temperature. /sup 3/H-GDP binding to BAT mitochondria increased more than 2-fold in 20 min when rats were moved from 27/sup 0/C to 4/sup 0/C. When rats housed at 4/sup 0/C for 2 h were returned to 27/sup 0/C, GDP binding decreased sharply in 20 min and returned to control levels in 2 h. On the other hand, GDP-inhibitable proton conductance, as measured by passive swelling in isotonic K-acetate of KCl buffers, was unaffected by brief cold exposure but more than doubled in rats kept at 4/sup 0/C for 10 days. The authors conclude that GDP-inhibitable swelling may be more indicative of uncoupling protein concentration whereas thermogenic activity is more appropriately indicated by GDP binding. GDP binding to BAT mitochondria from warm and acutely cold treated rats was not altered by prior swelling of the mitochondria nor by freeze-thawing the mitochondria before assay. Therefore, alterations of the number of GDP binding sites may not be a result of conformational changes of the mitochondril membrane.

  6. "Single-exposure" dual energy digital radiography in the detection of pulmonary nodules and calcifications.

    PubMed

    Oestmann, J W; Greene, R; Rhea, J T; Rosenthal, H; Koenker, R M; Tillotson, C L; Pearsen, K D; Hill, J W; Velaj, R H

    1989-07-01

    We studied the detectability of mineralized and non-mineralized simulated pulmonary nodules with dual energy digital radiography. "Soft tissue" and "bone" images (pixel size = 0.2 mm, 10 bits deep) were obtained with subtraction image processing after a single simultaneous exposure (100 kVp, 8 mAs, 17 mR skin exposure dose) of two storage phosphors with an interleaved 0.9 mm copper wafer. Three classes of paraffin-based nodules (0.5 to 3.0 cm) of varying mineral concentration (0, 120 and 190 mg/cm3 K2HPO4) were randomly positioned on the chest wall of two healthy volunteers to simulate calcified and non-calcified nodules. The average receiver operating characteristics (ROC) area of six readers (n = 2880 observations) showed that digital "bone" images (ROC area: 0.77 +/- 0.03) were significantly better (P less than 0.04) than conventional radiographs (OC Film, Lanex medium screens, 141 kVp, 19 mR skin exposure dose) (ROC area: 0.71 +/- 0.05) in detecting calcification in nodules. The unsubtracted digital images of lower kilovoltage were not superior to the 141 kVp conventional radiographs in a subgroup of two readers (ROC area: 0.73 +/- 0.02). Digital "soft tissue" images were equivalent to conventional chest radiographs in detecting soft tissue pulmonary nodules (ROC areas: 0.92 +/- 0.04 and 0.92 +/- 0.05, respectively. PMID:2753645

  7. Acute renal failure in 2 adult llamas after exposure to Oak trees (Quercus spp.)

    PubMed Central

    Chamorro, Manuel F.; Passler, Thomas; Joiner, Kellye; Poppenga, Robert H.; Bayne, Jenna; Walz, Paul H.

    2013-01-01

    Two adult llamas (Lama glama) previously exposed to oak trees (Quercus spp.) were presented with a history of depression and anorexia. Clinicopathological abnormalities included severe gastroenteritis, acute renal failure, and increased liver enzymes. This is believed to be the first report of oak toxicosis in South American camelids. PMID:23814303

  8. NEUROCHEMICAL EFFECTS OF CHRONIC DIETARY AND REPEATED HIGH-LEVEL ACUTE EXPOSURE TO CHLORPYRIFOS IN RATS.

    EPA Science Inventory

    Lots of information is available surrounding the acute toxicity of anticholinesterase pesticides, but these have been very few detailed studies on the chronic effects of these pesticides. Humans are exposed on a chronic basis and some humans believe that have been affected advers...

  9. BEHAVIORAL TOXICITY OF ACUTE AND SUBACUTE EXPOSURE TO TRIETHYLTIN IN THE RAT

    EPA Science Inventory

    Triethyltin (TET), the most toxic of the alkyltin compounds is used industrially as both a catalyst and a biocide (NIOSH, 1976). Stoner et al. (1955) determined the acute toxicity of a series of alkyltins and reported that in the rat, the LD50 for TET was 5.7 mg/kg. Barnes and St...

  10. Comparative cellular toxicity of titanium dioxide nanoparticles on human astrocyte and neuronal cells after acute and prolonged exposure.

    PubMed

    Coccini, Teresa; Grandi, Stefania; Lonati, Davide; Locatelli, Carlo; De Simone, Uliana

    2015-05-01

    Although in the last few decades, titanium dioxide nanoparticles (TiO₂NPs) have attracted extensive interest due to their use in wide range of applications, their influences on human health are still quite uncertain and less known. Evidence exists indicating TiO₂NPs ability to enter the brain, thus representing a realistic risk factor for both chronic and accidental exposure with the consequent needs for more detailed investigation on CNS. A rapid and effective in vitro test strategy has been applied to determine the effects of TiO₂NPs anatase isoform, on human glial (D384) and neuronal (SH-SY5Y) cell lines. Toxicity was assessed at different levels: mitochondrial function (by MTT), membrane integrity and cell morphology (by calcein AM/PI staining) after acute exposure (4-24-48 h) at doses from 1.5 to 250 μg/ml as well as growth and cell proliferation (by clonogenic test) after prolonged exposure (7-10 days) at sub-toxic concentrations (from 0.05 to 31 μg/ml). The cytotoxic effects of TiO₂NPs were compared with those caused by TiO₂ bulk counterpart treatment. Acute TiO₂NP exposure produced (i) dose- and time-dependent alterations of the mitochondrial function on D384 and SH-SY5Y cells starting at 31 and 15 μg/ml doses, respectively, after 24h exposure. SH-SY5Y were slightly more sensitive than D384 cells; and (ii) cell membrane damage occurring at 125 μg/ml after 24h exposure in both cerebral cells. Comparatively, the effects of TiO₂ bulk were less pronounced than those induced by nanoparticles in both cerebral cell lines. Prolonged exposure indicated that the proliferative capacity (colony size) was compromised at the extremely low TiO₂NP doses namely 1.5 μg/ml and 0.1 μg/ml for D384 and SH-SY5Y, respectively; cell sensitivity was still higher for SH-SY5Y compared to D384. Colony number decrease (15%) was also evidenced at ≥0.2 μg/ml TiO₂NP dose. Whereas, TiO₂ bulk treatment affected cell morphology only. TiO₂ internalization in SH

  11. Clinical and pathological manifestations of cardiovascular disease in rat models: the influence of acute ozone exposure

    EPA Science Inventory

    This paper shows that rat models of cardiovascular diseases have differential degrees of underlying pathologies at a young age. Rodent models of cardiovascular diseases (CVD) and metabolic disorders are used for examining susceptibility variations to environmental exposures. How...

  12. Acute Phase Response and Metabolic Syndrome Biomarkers of Libby Asbestos Exposure

    EPA Science Inventory

    Identification of biomarkers assists in the disease diagnosis and environmental health risk assessment. Exposure to Libby amphibole (LA) has been associated with increased cardiovascular mortality. We hypothesized that rats exposed to LA would present a unique serum proteomic pro...

  13. The Effects of In Vivo Acute Exposure to Polychlorinatedbiphenyls on Free and Total Thyroxine in Rats

    EPA Science Inventory

    Hypothyroxinemia in rats has been well documented as a result of either developmental or adult exposure to polychlorinated biphenyls (PCBs). Hypothetical mechanisms for this include induction of hepatic catabolic enzymes and cellular hormone transporters, and/or interference wit...

  14. Acute Phase Response, Inflammation and Metabolic Syndrome Biomarkers of Libby Asbestos Exposure

    EPA Science Inventory

    Background: Identification of biomarkers assists in the diagnosis of disease and the assessment of health risks from environmental exposures. Objective: We hypothesized that rats exposed to Libby amphibole (LA) would present with a unique serum proteomic profile which could help ...

  15. ACUTE EXPOSURE TO PARTICULATE MATTER IN A RAT MODEL OF HEART FAILURE

    EPA Science Inventory

    Human exposure to ambient particulate matter (PM) has been linked to cardiovascular morbidity and mortality. This association strengthens in people with preexisting cardiopulmonary diseases—especially heart failure (HF). To better characterize the cardiovascular effects of PM, we...

  16. Effects of muscular strength, exercise order, and acute whole-body vibration exposure on bat swing speed.

    PubMed

    Reyes, G F Cisco; Dickin, D Clark; Dolny, Dennis G; Crusat, Nolan J K

    2010-12-01

    The purposes for this study were to investigate effects of acute whole-body vibration (WBV) exposure and exercise order on bat speed and to examine relationship between muscular strength and bat speed. All participants were recreationally trained men (n = 16; 22 ± 2 years; 181.4 ± 7.4 cm; 84.7 ± 9 kg), with previous baseball experience and were tested for 1 repetitive maximum (1RM) strength in squat and bench press. Subjects then participated in 4 randomized sessions on separate days, each consisting of 3 sets of 5 bat swings. Exercises (upper and lower body dynamic and static movements related to bat swing) with or without WBV exposure were performed after sets 1 and 2. Trials were as follows: no-exercise Control (CTRL), upper body followed by lower body exercises without WBV (Arm-Leg NOVIB), upper body followed by lower body exercises with WBV (Arm-Leg VIB), and lower body followed by upper body exercises with WBV (Leg-Arm VIB). Bat speed was recorded during each swing and averaged across sets. Statistical analyses were performed to assess differences across sets and trials. Linear regressions analyzed relationship between strength and bat speed. A significant relationship existed between bat speed and lower body strength (r = 0.406, p = 0.008) but not for upper body strength. The exercise order of Arm-Leg VIB significantly increased bat speed by 2.6% (p = 0.02). Performing identical order of exercises without vibration (Arm-Leg NOVIB) significantly decreased bat speed by 2% (p = 0.039). It was concluded that adding vibration exposure to total-body exercises can provide acute enhancements in bat speed. Additionally, leg strength was shown to influence bat speed suggesting that increasing leg strength may enhance bat speed. PMID:21088545

  17. Left Ventricular Function during Acute High-Altitude Exposure in a Large Group of Healthy Young Chinese Men

    PubMed Central

    Rao, Mingyue; Li, Jiabei; Qin, Jun; Zhang, Jihang; Gao, Xubin; Yu, Shiyong; Yu, Jie; Chen, Guozhu; Xu, Baida; Li, Huijie; Rao, Rongsheng; Huang, Lan; Jin, Jun

    2015-01-01

    Objective The purpose of this study was to observe left ventricular function during acute high-altitude exposure in a large group of healthy young males. Methods A prospective trial was conducted in Szechwan and Tibet from June to August, 2012. By Doppler echocardiography, left ventricular function was examined in 139 healthy young Chinese men at sea level; within 24 hours after arrival in Lhasa, Tibet, at 3700 m; and on day 7 following an ascent to Yangbajing at 4400 m after 7 days of acclimatization at 3700 m. The resting oxygen saturation (SaO2), heart rate (HR) and blood pressure (BP) were also measured at the above mentioned three time points. Results Within 24 hours of arrival at 3700 m, the HR, ejection fraction (EF), fractional shortening (FS), stroke volume (SV), cardiac output (CO), and left ventricular (LV) Tei index were significantly increased, but the LV end-systolic dimension (ESD), end-systolic volume (ESV), SaO2, E/A ratio, and ejection time (ET) were significantly decreased compared to the baseline levels in all subjects. On day 7 at 4400 m, the SV and CO were significantly decreased; the EF and FS Tei were not decreased compared with the values at 3700 m; the HR was further elevated; and the SaO2, ESV, ESD, and ET were further reduced. Additionally, the E/A ratio was significantly increased on day 7 but was still lower than it was at low altitude. Conclusion Upon acute high-altitude exposure, left ventricular systolic function was elevated with increased stroke volume, but diastolic function was decreased in healthy young males. With higher altitude exposure and prolonged acclimatization, the left ventricular systolic function was preserved with reduced stroke volume and improved diastolic function. PMID:25629435

  18. Influence of acute smoking exposure on the subsequent reinforcing value of smoking.

    PubMed

    Perkins, K A; Grobe, J; Fonte, C

    1997-08-01

    The reinforcing value of smoking (i.e., the degree to which a smoker will work to obtain smoking) after varying the magnitude of prior smoke exposure in smokers not trying to quit was examined. Eight men and 8 women participated in 5 sessions involving manipulation of prior exposure to smoking: 0, 2, 6, or 12 puffs after overnight smoking abstinence or ad-lib smoking before the session. After exposure, participants engaged in a computer task involving concurrent schedules of reinforcement for smoke puffs (16% all trials) versus money (4-64%). Only the greatest amount of prior exposure (ad lib) produced a significant reduction in subsequent responding for smoke puffs. No exposure condition significantly increased responding above that for 0 puffs, indicating no priming effect. By contrast, self-report measures of desire to smoke and amount of money participants would pay for a cigarette declined sharply with greater prior exposure. These measures were correlated only weakly with smoke-reinforced responding on the behavioral task, suggesting that subjective versus behavioral measures assess different dimensions of smoking's reward value. PMID:9260076

  19. Murine melanomas accelerated by a single UVR exposure carry photoproduct footprints but lack UV signature C>T mutations in critical genes.

    PubMed

    Mukhopadhyay, P; Ferguson, B; Muller, H K; Handoko, H Y; Walker, G J

    2016-06-23

    Ultraviolet radiation (UVR) exposure increases malignant melanoma (MM) risk, but in the context of acute, not cumulative exposure. C>T and CC>TT changes make up the overwhelming majority of single base substitutions (SBS) in MM DNA, as both precursor melanocytes and melanocytic lesions have incurred incidental exposures to sunlight. To study the mutagenic mechanisms by which acute sunburn accelerates MM, we sequenced the exomes of spontaneous and neonatal UVB-induced Cdk4-R24C::Tyr-NRASQ61K mouse MMs. UVR-induced MMs carried more SBSs than spontaneous MMs, but the levels of genomic instability, reflected by translocations and copy number changes, were not different. C>T/G>A was the most common SBS in spontaneous and UVR-induced MMs, only modestly increased in the latter. However, they tended to occur at the motif A/GpCpG (reflecting C>T transition due to spontaneous deamination of cytosine at CpG) in spontaneous MMs, and T/CpCpC/T (reflecting the effects of pyrimidine dimers on either side of the mutated C) in UVR-induced MMs. Unlike MMs associated with repetitive exposures, we observed no CC>TT changes. In addition, we also found UVR 'footprints' at T>A/A>Ts (at NpTpT) and T>C/A>G (at CpTpC). These footprints are also present in MMs from a chronic UVR mouse model, and in some human MMs, suggesting that they may be minor UVR signature changes. We found few significantly somatically mutated genes (~6 per spontaneous and 15 per UVR-induced melanoma) in addition to the Cdk4 and NRAS mutations already present. Trp53 was the most convincing recurrently mutated gene; however, in the UVR-induced MMs no Trp53 mutations were at C>T/G>A, suggesting that it was probably mutated during tumour progression, not directly induced by UVR photoproducts. The very low load of recurrent mutations convincingly induced by classical UVB-induced dimer photoproducts may support a role for cell extrinsic mechanisms, such as photoimmunosuppression and inflammation in driving MM after acute

  20. Mimicking exposures to acute and lifetime concentrations of inhaled silver nanoparticles by two different in vitro approaches

    PubMed Central

    Herzog, Fabian; Loza, Kateryna; Balog, Sandor; Clift, Martin J D; Epple, Matthias; Gehr, Peter; Petri-Fink, Alke

    2014-01-01

    Summary In the emerging market of nano-sized products, silver nanoparticles (Ag NPs) are widely used due to their antimicrobial properties. Human interaction with Ag NPs can occur through the lung, skin, gastrointestinal tract, and bloodstream. However, the inhalation of Ag NP aerosols is a primary concern. To study the possible effects of inhaled Ag NPs, an in vitro triple cell co-culture model of the human alveolar/airway barrier (A549 epithelial cells, human peripheral blood monocyte derived dendritic and macrophage cells) together with an air–liquid interface cell exposure (ALICE) system was used in order to reflect a real-life exposure scenario. Cells were exposed at the air–liquid interface (ALI) to 0.03, 0.3, and 3 µg Ag/cm2 of Ag NPs (diameter 100 nm; coated with polyvinylpyrrolidone: PVP). Ag NPs were found to be highly aggregated within ALI exposed cells with no impairment of cell morphology. Furthermore, a significant increase in release of cytotoxic (LDH), oxidative stress (SOD-1, HMOX-1) or pro-inflammatory markers (TNF-α, IL-8) was absent. As a comparison, cells were exposed to Ag NPs in submerged conditions to 10, 20, and 30 µg Ag/mL. The deposited dose per surface area was estimated by using a dosimetry model (ISDD) to directly compare submerged vs ALI exposure concentrations after 4 and 24 h. Unlike ALI exposures, the two highest concentrations under submerged conditions promoted a cytotoxic and pro-inflammatory response after 24 h. Interestingly, when cell cultures were co-incubated with lipopolysaccharide (LPS), no synergistic inflammatory effects were observed. By using two different exposure scenarios it has been shown that the ALI as well as the suspension conditions for the lower concentrations after 4 h, reflecting real-life concentrations of an acute 24 h exposure, did not induce any adverse effects in a complex 3D model mimicking the human alveolar/airway barrier. However, the highest concentrations used in the ALI setup, as well as

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

    PubMed

    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

  2. Maternal Benzene Exposure during Pregnancy and Risk of Childhood Acute Lymphoblastic Leukemia: A Meta-Analysis of Epidemiologic Studies

    PubMed Central

    Li, Zhen; Zhu, Jie; Bi, Yongyi; Bai, YuE; Wang, Hong

    2014-01-01

    Background The prevalence of childhood leukemia is increasing rapidly all over the world. However, studies on maternal benzene exposure during pregnancy and childhood acute lymphoblastic leukemia (ALL) have not been systematically assessed. Therefore, we performed a meta-analysis to investigate the association between maternal solvent, paint, petroleum exposure, and smoking during pregnancy and risk of childhood ALL. Methods Relevant studies up to September 1st, 2013 were identified by searching the PubMed, EMBASE, Cochrane library and the Web of Science databases. The effects were pooled using either fixed or random effect models based on the heterogeneity of the studies. Results Twenty-eight case-control studies and one cohort study were included for analysis, with a total of 16,695 cases and 1,472,786 controls involved. Pooled odds ratio (OR) with 95% confidence interval (CI) for ALL was 1.25 (1.09, 1.45) for solvent, 1.23 (1.02, 1.47) for paint, 1.42 (1.10, 1.84) for petroleum exposure, and 0.99 (0.93, 1.06) for maternal smoking during pregnancy. No publication bias was found in this meta-analysis and consistent results were observed for subgroup and sensitivity analyses. Conclusions Childhood ALL was associated with maternal solvent, paint, and petroleum exposure during pregnancy. No association was found between ALL and maternal smoking during pregnancy. Avoidance of maternal occupational and environmental benzene exposure during pregnancy could contribute to a decrease in the risk of childhood ALL. PMID:25333868

  3. Cardiac and mitochondrial dysfunction following acute pulmonary exposure to mountaintop removal mining particulate matter.

    PubMed

    Nichols, Cody E; Shepherd, Danielle L; Knuckles, Travis L; Thapa, Dharendra; Stricker, Janelle C; Stapleton, Phoebe A; Minarchick, Valerie C; Erdely, Aaron; Zeidler-Erdely, Patti C; Alway, Stephen E; Nurkiewicz, Timothy R; Hollander, John M

    2015-12-15

    Throughout the United States, air pollution correlates with adverse health outcomes, and cardiovascular disease incidence is commonly increased following environmental exposure. In areas surrounding active mountaintop removal mines (MTM), a further increase in cardiovascular morbidity is observed and may be attributed in part to particulate matter (PM) released from the mine. The mitochondrion has been shown to be central in the etiology of many cardiovascular diseases, yet its roles in PM-related cardiovascular effects are not realized. In this study, we sought to elucidate the cardiac processes that are disrupted following exposure to mountaintop removal mining particulate matter (PM MTM). To address this question, we exposed male Sprague-Dawley rats to PM MTM, collected within one mile of an active MTM site, using intratracheal instillation. Twenty-four hours following exposure, we evaluated cardiac function, apoptotic indices, and mitochondrial function. PM MTM exposure elicited a significant decrease in ejection fraction and fractional shortening compared with controls. Investigation into the cellular impacts of PM MTM exposure identified a significant increase in mitochondrial-induced apoptotic signaling, as reflected by an increase in TUNEL-positive nuclei and increased caspase-3 and -9 activities. Finally, a significant increase in mitochondrial transition pore opening leading to decreased mitochondrial function was identified following exposure. In conclusion, our data suggest that pulmonary exposure to PM MTM increases cardiac mitochondrial-associated apoptotic signaling and decreases mitochondrial function concomitant with decreased cardiac function. These results suggest that increased cardiovascular disease incidence in populations surrounding MTM mines may be associated with increased cardiac cell apoptotic signaling and decreased mitochondrial function. PMID:26497962

  4. Effects of dexamethasone on functional and pathological changes in rat bronchi caused by high acute exposure to chlorine.

    PubMed

    Demnati, R; Fraser, R; Martin, J G; Plaa, G; Malo, J L

    1998-10-01

    We assessed the effects of dexamethasone on functional and histological changes after acute exposure to a high level of chlorine gas in an animal model of reactive airways dysfunction syndrome (RADS). Sprague-Dawley male rats were exposed to 1500 ppm of chlorine for 5 min and treated with either dexamethasone (dex; 300 micrograms/kg/day) or saline intraperitoneally for 7 days. Lung resistance (RL), airway responsiveness to inhaled methacholine (MCh), airway wall morphometric measurements, and bronchoalveolar lavage (BAL) cells were assessed over a 2-week period after exposure. Dex administration significantly attenuated both chlorine-induced increased RL and chlorine-induced increased responsiveness to methacholine compared with saline: -2.7 +/- 6.8% vs 102.3 +/- 36.6% change from baseline RL (P < 0.01) and 2.5 +/- 0.6 mg/ml vs 1.2 +/- 0.7 mg/ml in the MCh concentration required to double the RL from baseline (P < 0.01). There was a tendency, albeit nonsignificant, for improvement in some indices of epithelial injury. Dex significantly attenuated the postexposure neutrophilic cellular response in BAL 1 day after exposure (15.8 +/- 4.9% neutrophils in the dex group vs 49.8 +/- 2.7% neutrophils in the saline group) (P < or = 0.001). Our results show that dex administration helps maintain pulmonary function, reduces BAL inflammatory cell number, and tends to improve some morphometric airway wall structure parameters in rats exposed to chlorine. PMID:9848131

  5. Effect of acute copper sulfate exposure on olfactory responses to amino acids and pheromones in goldfish (Carassius auratus).

    PubMed

    Kolmakov, Nikolay N; Hubbard, Peter C; Lopes, Orlando; Canario, Adelino V M

    2009-11-01

    Exposure of olfactory epithelium to environmentally relevant concentrations of copper disrupts olfaction in fish. To examine the dynamics of recovery at both functional and morphological levels after acute copper exposure, unilateral exposure of goldfish olfactory epithelia to 100 microM CuSO(4) (10 min) was followed by electro-olfactogram (EOG) recording and scanning electron microscopy. Sensitivity to amino acids (l-arginine and l-serine), generally considered food-related odorants, recovered most rapidly (three days), followed by that to catecholamines (3-O-methoxytyramine), bile acids (taurolithocholic acid) and the steroid pheromone, 17,20beta-dihydroxy-4-pregnen-3-one 20-sulfate, which took 28 days to reach full recovery. Sensitivity to the postovulatory pheromone prostaglandin F(2alpha) had not fully recovered even at 28 days. These changes in sensitivity were correlated with changes in the recovery of ciliated and microvillous receptor cell types. Microvillous cells appeared largely unaffected by CuSO(4) treatment. Cilia in ciliated receptor neurones, however, appeared damaged one day post-treatment and were virtually absent after three days but had begun to recover after 14 days. Together, these results support the hypothesis that microvillous receptor neurones detect amino acids whereas ciliated receptor neurones were not functional and are responsible for detection of social stimuli (bile acids and pheromones). Furthermore, differences in sensitivity to copper may be due to different transduction pathways in the different cell types. PMID:19924975

  6. Strain- and context-dependent behavioural responses of acute alarm substance exposure in zebrafish.

    PubMed

    Quadros, Vanessa A; Silveira, Ariane; Giuliani, Giulie S; Didonet, Fernanda; Silveira, Alessandra S; Nunes, Mauro E; Silva, Tális O; Loro, Vania L; Rosemberg, Denis B

    2016-01-01

    We investigate the behavioural responses of wild type (WT) and leopard (leo) zebrafish elicited by alarm substances of conspecifics at three contexts: during the exposure period (Experiment 1); after exposure, in habituation to novelty (Experiment 2); or after exposure, in the light-dark preference test (Experiment 3), and analyse their influence on pigment response. During the exposure, leo showed decreased vertical drifts, increased number and duration of erratic movements, while WT had increased erratic movements and latency to enter the top. In the novel tank, we observed that angular velocity decreased in WT exposed to alarm substance, which also presented increased fear responses. Contrastingly, leo increased the number of entries and time in top, indicating differences in habituation profile. Alarm substance increased the number of erratic movements in the light-dark test, but elicited different responses between strains in scototaxis, latency to enter the dark compartment and risk assessment episodes. Moreover, the body colour of zebrafish did not change after alarm substance exposure. Principal component analyses suggest that burst swimming, anxiety-like behaviours, and locomotion/exploration were the components that most accounted for total variances of Experiments 1, 2, and 3, respectively. We conclude that chemical cue from conspecifics triggers strain- and context-dependent responses. PMID:26524408

  7. Probabilistic acute dietary exposure assessment of the Chinese population to cypermethrin residues.

    PubMed

    Sun, J-F; Liu, P; Li, C-Y; Li, J-X; Wang, C-N; Min, J; Hu, D; Wu, Y-N

    2011-01-01

    A probabilistic estimation of dietary exposure to cypermethrin residues for the Chinese population was performed. Cypermethrin residue data were obtained from the national food contamination monitoring program for 2001-2006, encompassing 14,096 samples from 36 commodities with a detection rate of 10.4%. Food consumption data were gathered from the national nutrition and health survey conducted in 2002, comprising 65,915 consumers aged 2-100 years and 3701 children of 2-6 years old. The whole country was roughly divided into six regions and the ranges of the median and of P99.9 exposure estimated for these regions were 0.018-0.026 and 3.131-7.095 µg kg(-1 )bw day(-1), respectively. Pak-choi and Chinese cabbage contributed 33.9 and 13.2%, respectively, to the cypermethrin intake for the general population, while pak-choi and citrus covered 30.7 and 22.5% of the total intake for children, respectively. The exposure of the rural population was higher than urban populations. Rural areas mainly located in the plains of central China had among the highest exposure of the six regions, accounting for 17.7% of the ARfD at P99.9, while the 99.99th percentile of exposure for children, especially rural children, far exceeded the ARfD, which is a cause for concern. PMID:21598132

  8. Effect of acute exposure to ozone on heart rate and blood pressure of the conscious rat

    SciTech Connect

    Uchiyama, I.; Simomura, Y.; Yokoyama, E.

    1985-12-01

    Electrocardiogram and arterial blood pressure in conscious and unrestrained rats of various ages were recorded during a 3-hr exposure to filtered air or 1 ppm ozone (O/sub 3/). In general, heart rate and mean arterial blood pressure of rats significantly decreased during exposure to O/sub 3/, whereas these functional parameters remained almost stable during exposure to filtered air. Heart rate usually reached a plateau during the exposure to O/sub 3/. Additionally, PR interval and QRS complex significantly increased and premature atrial contraction and incomplete A-V block were frequently observed during the exposure to O/sub 3/. These circulatory effects of O/sub 3/ were more markedly manifested by rats 11 weeks old than either those 8 or 4 weeks old. On the other hand, no significant difference in the circulatory responses was observed between male and female rats. These circulatory effects of O/sub 3/ may be significant from the viewpoint of health effects, although its mechanisms remain unsolved.

  9. Time-course of functional and pathological changes after a single high acute inhalation of chlorine in rats.

    PubMed

    Demnati, R; Fraser, R; Ghezzo, H; Martin, J G; Plaa, G; Malo, J L

    1998-04-01

    Reactive airways dysfunction syndrome (RADS) is an asthma-like condition that follows exposure to very high concentrations of an irritant material. We assessed the time-course of pathophysiological alterations in a model of RADS. Sprague-Dawley rats were exposed to 1,500 parts per million (ppm) of chlorine for 5 min. Lung resistance (RL), responsiveness to inhaled methacholine (MCh), the airway epithelium and bronchoalveolar lavage (BAL) were assessed over a 3 month period after exposure. RL increased significantly up to 3 days after exposure, reaching a maximal change of 110+/-16% from baseline. There was a significant decrease in the concentration of MCh required to increase RL by 0.20 cmH2O x mL(-1) x s from days 1-7 after exposure. In some rats, MCh hyperresponsiveness and RL changes persisted after exposure for as long as 1 and 3 months, respectively. Histological evaluation with morphometric evaluation revealed epithelial flattening, necrosis, increase in smooth muscle mass and evidence of epithelial regeneration. BAL showed an increased number of neutrophils. The timing of maximal abnormality in the appearance of the epithelium (days 1-3) corresponded to that of the maximal functional changes. Acute high chlorine exposure results in functional and pathological abnormalities that resolve in the majority of animals after a variable period; however, these changes can persist in some animals. Functional abnormalities in the initial stages may be related to airway epithelial damage. PMID:9623698

  10. Dose-related gene expression changes in forebrain following acute, low-level chlorpyrifos exposure in neonatal rats

    SciTech Connect

    Ray, Anamika; Liu Jing; Ayoubi, Patricia; Pope, Carey

    2010-10-15

    Chlorpyrifos (CPF) is a widely used organophosphorus insecticide (OP) and putative developmental neurotoxicant in humans. The acute toxicity of CPF is elicited by acetylcholinesterase (AChE) inhibition. We characterized dose-related (0.1, 0.5, 1 and 2 mg/kg) gene expression profiles and changes in cell signaling pathways 24 h following acute CPF exposure in 7-day-old rats. Microarray experiments indicated that approximately 9% of the 44,000 genes were differentially expressed following either one of the four CPF dosages studied (546, 505, 522, and 3,066 genes with 0.1, 0.5, 1.0 and 2.0 mg/kg CPF). Genes were grouped according to dose-related expression patterns using K-means clustering while gene networks and canonical pathways were evaluated using Ingenuity Pathway Analysis (registered) . Twenty clusters were identified and differential expression of selected genes was verified by RT-PCR. The four largest clusters (each containing from 276 to 905 genes) constituted over 50% of all differentially expressed genes and exhibited up-regulation following exposure to the highest dosage (2 mg/kg CPF). The total number of gene networks affected by CPF also rose sharply with the highest dosage of CPF (18, 16, 18 and 50 with 0.1, 0.5, 1 and 2 mg/kg CPF). Forebrain cholinesterase (ChE) activity was significantly reduced (26%) only in the highest dosage group. Based on magnitude of dose-related changes in differentially expressed genes, relative numbers of gene clusters and signaling networks affected, and forebrain ChE inhibition only at 2 mg/kg CPF, we focused subsequent analyses on this treatment group. Six canonical pathways were identified that were significantly affected by 2 mg/kg CPF (MAPK, oxidative stress, NF{Kappa}B, mitochondrial dysfunction, arylhydrocarbon receptor and adrenergic receptor signaling). Evaluation of different cellular functions of the differentially expressed genes suggested changes related to olfactory receptors, cell adhesion/migration, synapse

  11. Effects of acute versus repeated cocaine exposure on the expression of endocannabinoid signaling-related proteins in the mouse cerebellum.

    PubMed

    Palomino, Ana; Pavón, Francisco-Javier; Blanco-Calvo, Eduardo; Serrano, Antonia; Arrabal, Sergio; Rivera, Patricia; Alén, Francisco; Vargas, Antonio; Bilbao, Ainhoa; Rubio, Leticia; Rodríguez de Fonseca, Fernando; Suárez, Juan

    2014-01-01

    Growing awareness of cerebellar involvement in addiction is based on the cerebellum's intermediary position between motor and reward, potentially acting as an interface between motivational and cognitive functions. Here, we examined the impact of acute and repeated cocaine exposure on the two main signaling systems in the mouse cerebellum: the endocannabinoid (eCB) and glutamate systems. To this end, we investigated whether eCB signaling-related gene and protein expression {cannabinoid receptor type 1 receptors and enzymes that produce [diacylglycerol lipase alpha/beta (DAGLα/β) and N-acyl phosphatidylethanolamine phospholipase D (NAPE-PLD)] and degrade [monoacylglycerol lipase (MAGL) and fatty acid amino hydrolase (FAAH)] eCB} were altered. In addition, we analyzed the gene expression of relevant components of the glutamate signaling system [glutamate synthesizing enzymes liver-type glutaminase isoform (LGA) and kidney-type glutaminase isoform (KGA), metabotropic glutamatergic receptor (mGluR3/5), NMDA-ionotropic glutamatergic receptor (NR1/2A/2B/2C) and AMPA-ionotropic receptor subunits (GluR1/2/3/4)] and the gene expression of tyrosine hydroxylase (TH), the rate-limiting enzyme in catecholamine biosynthesis, because noradrenergic terminals innervate the cerebellar cortex. Results indicated that acute cocaine exposure decreased DAGLα expression, suggesting a down-regulation of 2-arachidonylglycerol (2-AG) production, as well as gene expression of TH, KGA, mGluR3 and all ionotropic receptor subunits analyzed in the cerebellum. The acquisition of conditioned locomotion and sensitization after repeated cocaine exposure were associated with an increased NAPE-PLD/FAAH ratio, suggesting enhanced anandamide production, and a decreased DAGLβ/MAGL ratio, suggesting decreased 2-AG generation. Repeated cocaine also increased LGA gene expression but had no effect on glutamate receptors. These findings indicate that acute cocaine modulates the expression of the eCB and

  12. Effects of acute versus repeated cocaine exposure on the expression of endocannabinoid signaling-related proteins in the mouse cerebellum

    PubMed Central

    Palomino, Ana; Pavón, Francisco-Javier; Blanco-Calvo, Eduardo; Serrano, Antonia; Arrabal, Sergio; Rivera, Patricia; Alén, Francisco; Vargas, Antonio; Bilbao, Ainhoa; Rubio, Leticia; Rodríguez de Fonseca, Fernando; Suárez, Juan

    2014-01-01

    Growing awareness of cerebellar involvement in addiction is based on the cerebellum’s intermediary position between motor and reward, potentially acting as an interface between motivational and cognitive functions. Here, we examined the impact of acute and repeated cocaine exposure on the two main signaling systems in the mouse cerebellum: the endocannabinoid (eCB) and glutamate systems. To this end, we investigated whether eCB signaling-related gene and protein expression {cannabinoid receptor type 1 receptors and enzymes that produce [diacylglycerol lipase alpha/beta (DAGLα/β) and N-acyl phosphatidylethanolamine phospholipase D (NAPE-PLD)] and degrade [monoacylglycerol lipase (MAGL) and fatty acid amino hydrolase (FAAH)] eCB} were altered. In addition, we analyzed the gene expression of relevant components of the glutamate signaling system [glutamate synthesizing enzymes liver-type glutaminase isoform (LGA) and kidney-type glutaminase isoform (KGA), metabotropic glutamatergic receptor (mGluR3/5), NMDA-ionotropic glutamatergic receptor (NR1/2A/2B/2C) and AMPA-ionotropic receptor subunits (GluR1/2/3/4)] and the gene expression of tyrosine hydroxylase (TH), the rate-limiting enzyme in catecholamine biosynthesis, because noradrenergic terminals innervate the cerebellar cortex. Results indicated that acute cocaine exposure decreased DAGLα expression, suggesting a down-regulation of 2-arachidonylglycerol (2-AG) production, as well as gene expression of TH, KGA, mGluR3 and all ionotropic receptor subunits analyzed in the cerebellum. The acquisition of conditioned locomotion and sensitization after repeated cocaine exposure were associated with an increased NAPE-PLD/FAAH ratio, suggesting enhanced anandamide production, and a decreased DAGLβ/MAGL ratio, suggesting decreased 2-AG generation. Repeated cocaine also increased LGA gene expression but had no effect on glutamate receptors. These findings indicate that acute cocaine modulates the expression of the eCB and

  13. Acute high-level exposure to WTC particles alters expression of genes associated with oxidative stress and immune function in the lung

    PubMed Central

    Cohen, Mitchell D.; Vaughan, Joshua M.; Garrett, Brittany; Prophete, Colette; Horton, Lori; Sisco, Maureen; Kodavanti, Urmila P.; Ward, William O.; Peltier, Richard E.; Zelikoff, Judith; Chen, Lung-chi

    2015-01-01

    First responders (FR) present at Ground Zero in the first 72 h after the World Trade Center (WTC) collapsed have progressively exhibited significant respiratory injuries. The few toxicology studies performed to date evaluated effects from just fine (<2.5 µm) WTC dusts; none examined health effects/toxicities from atmospheres bearing larger particle sizes, despite the fact the majority (496%) of dusts were >10µm and most FR likely entrained dusts by mouth breathing. Using a system that generated/delivered supercoarse (10–53 µm) WTC dusts to F344 rats (in a manner that mimicked FR exposures), this study sought to examine potential toxicities in the lungs. In this exploratory study, rats were exposed for 2 h to 100 mg WTC dust/m3 (while under isoflurane [ISO] anesthesia) or an air/ISO mixture; this dose conservatively modeled likely exposures by mouth-breathing FR facing ≈750–1000 mg WTC dust/m3. Lungs were harvested 2 h post-exposure and total RNA extracted for subsequent global gene expression analysis. Among the > 1000 genes affected by WTC dust (under ISO) or ISO alone, 166 were unique to the dust exposure. In many instances, genes maximally-induced by the WTC dust exposure (relative to in naïve rats) were unchanged/inhibited by ISO only; similarly, several genes maximally inhibited in WTC dust rats were largely induced/unchanged in rats that received ISO only. These outcomes reflect likely contrasting effects of ISO and the WTC dust on lung gene expression. Overall, the data show that lungs of rats exposed to WTC dust (under ISO) – after accounting for any impact from ISO alone – displayed increased expression of genes related to lung inflammation, oxidative stress, and cell cycle control, while several involved in anti-oxidant function were inhibited. These changes suggested acute inflammogenic effects and oxidative stress in the lungs of WTC dust-exposed rats. This study, thus, concludes that a single very high exposure to WTC dusts could

  14. Acute high-level exposure to WTC particles alters expression of genes associated with oxidative stress and immune function in the lung.

    PubMed

    Cohen, Mitchell D; Vaughan, Joshua M; Garrett, Brittany; Prophete, Colette; Horton, Lori; Sisco, Maureen; Kodavanti, Urmila P; Ward, William O; Peltier, Richard E; Zelikoff, Judith; Chen, Lung-chi

    2015-01-01

    First responders (FR) present at Ground Zero in the first 72 h after the World Trade Center (WTC) collapsed have progressively exhibited significant respiratory injuries. The few toxicology studies performed to date evaluated effects from just fine (< 2.5 µm) WTC dusts; none examined health effects/toxicities from atmospheres bearing larger particle sizes, despite the fact the majority (> 96%) of dusts were > 10 µm and most FR likely entrained dusts by mouth breathing. Using a system that generated/delivered supercoarse (10-53 µm) WTC dusts to F344 rats (in a manner that mimicked FR exposures), this study sought to examine potential toxicities in the lungs. In this exploratory study, rats were exposed for 2 h to 100 mg WTC dust/m(3) (while under isoflurane [ISO] anesthesia) or an air/ISO mixture; this dose conservatively modeled likely exposures by mouth-breathing FR facing ≈750-1000 mg WTC dust/m(3). Lungs were harvested 2 h post-exposure and total RNA extracted for subsequent global gene expression analysis. Among the >  1000 genes affected by WTC dust (under ISO) or ISO alone, 166 were unique to the dust exposure. In many instances, genes maximally-induced by the WTC dust exposure (relative to in naïve rats) were unchanged/inhibited by ISO only; similarly, several genes maximally inhibited in WTC dust rats were largely induced/unchanged in rats that received ISO only. These outcomes reflect likely contrasting effects of ISO and the WTC dust on lung gene expression. Overall, the data show that lungs of rats exposed to WTC dust (under ISO) - after accounting for any impact from ISO alone - displayed increased expression of genes related to lung inflammation, oxidative stress, and cell cycle control, while several involved in anti-oxidant function were inhibited. These changes suggested acute inflammogenic effects and oxidative stress in the lungs of WTC dust-exposed rats. This study, thus, concludes that a single very high exposure

  15. Elimination of 2,4,5,2',4',5'-hexachlorobiphenyl by the purple sea urchin, Strongylocentrotus purpuratus, following single exposure

    SciTech Connect

    Tjeerdema, R.S.; Jacobs, R.S.

    1987-06-01

    Understanding the fate of a single PCB isomer in a resident species may aid in assessing the risk to the marine community. Therefore, the elimination of 2,4,5,2',4',5'-hexachlorobiphenyl (HCBP) by the purple sea urchin, Strongylocentrotus purpuratus, following a single exposure, was investigated. The purple sea urchin was chosen because of its economic importance and ability to proliferate in certain polluted conditions. Single exposure may best mimic the effects of intermittent oceanic incineration or disposal, and 2,4,5,2',4',5'-HCBP was chosen due to its presence in common PCB mixtures and high chlorine content, thus strong lipophilicity.

  16. Effect of acute ozone exposure on the proteinase-antiproteinase balance in the rat lung

    SciTech Connect

    Pickrell, J.A.; Gregory, R.E.; Cole, D.J.; Hahn, F.F.; Henderson, R.F.

    1987-04-01

    Lung disease may result from a persisting proteinase excess or a depletion of antiproteinase in pulmonary parenchyma. We investigated the in vivo effect of a 48-hr exposure to ozone at 0.5, 1.0, or 1.5 ppm on proteinase and antiproteinase activity of rat lungs. Elastase inhibitory capacities of serum, lung tissue, and airway washings were measured as indicators of antielastase activity. Trypsin inhibitory capacity was measured using an esterolytic procedure. Proteinase was measured as radioactive release from a /sup 14/C-globin substrate. The 48-hr exposures to O/sub 3/ at levels up to 1 ppm produced concentration-dependent decreases of 35-80% of antiproteinase activities in serum and in lung tissue. However, exposure to 1.5 ppm O/sub 3/ resulted in no decrease in antiproteinase activities. Acid proteinase activities (pH 4.2) were increased 65-120% by exposure to 1 or 1.5 ppm O/sub 3/, which correlated with inflammatory cells noted histologically. At 1.5 ppm O/sub 3/, pulmonary edema and hemorrhage were noted in histologic sections. These changes led to a flooding of the alveoli with up to 40 times normal protein levels and a greater than fivefold increase in airway antiproteinase. These data suggest that serum and soluble lung tissue antiproteinase activity decreased upon exposure to low levels of ozone. However, if O/sub 3/ exposure is high enough to produce pulmonary hemorrhage, antiproteinase may increase following serum exudation. These changes may be important in the development of ozone-induced lung diseases, especially emphysema.

  17. Effect of acute ozone exposure on the proteinase-antiproteinase balance in the rat lung.

    PubMed

    Pickrell, J A; Gregory, R E; Cole, D J; Hahn, F F; Henderson, R F

    1987-04-01

    Lung disease may result from a persisting proteinase excess or a depletion of antiproteinase in pulmonary parenchyma. We investigated the in vivo effect of a 48-hr exposure to ozone at 0.5, 1.0, or 1.5 ppm on proteinase and antiproteinase activity of rat lungs. Elastase inhibitory capacities of serum, lung tissue, and airway washings were measured as indicators of antielastase activity. Trypsin inhibitory capacity was measured using an esterolytic procedure. Proteinase was measured as radioactive release from a 14C-globin substrate. The 48-hr exposures to O3 at levels up to 1 ppm produced concentration-dependent decreases of 35-80% of antiproteinase activities in serum and in lung tissue. However, exposure to 1.5 ppm O3 resulted in no decrease in antiproteinase activities. Acid proteinase activities (pH 4.2) were increased 65-120% by exposure to 1 or 1.5 ppm O3, which correlated with inflammatory cells noted histologically. At 1.5 ppm O3, pulmonary edema and hemorrhage were noted in histologic sections. These changes led to a flooding of the alveoli with up to 40 times normal protein levels and a greater than fivefold increase in airway antiproteinase. These data suggest that serum and soluble lung tissue antiproteinase activity decreased upon exposure to low levels of ozone. However, if O3 exposure is high enough to produce pulmonary hemorrhage, antiproteinase may increase following serum exudation. These changes may be important in the development of ozone-induced lung diseases, especially emphysema. PMID:3549351

  18. Changes of pathological and physiological indicators affecting drug metabolism in rats after acute exposure to high altitude

    PubMed Central

    LI, WENBIN; WANG, RONG; XIE, HUA; ZHANG, JUANHONG; JIA, ZHENGPING

    2015-01-01

    High altitude environments cause the human body to undergo a series of pathological, physiological and biochemical changes, which have a certain effect on drug pharmacokinetics. The objective of the present study was to observe changes in factors affecting pharmacokinetics in rats following acute exposure to high altitude and return to low altitude. A total of 21 male Wistar rats were randomly assigned to three groups. The rats in group A were maintained at low altitude in Shanghai, 55 m above sea level; those in group B were acutely exposed to high altitude in Maqu, Gansu, 4,010 m above sea level; and those in group C were acutely exposed to high altitude and then returned to low altitude. Blood was collected from the orbit for the analysis of significant biochemical indicators and from the abdominal aorta for blood gas analysis. Brain, lung and kidney tissues were removed to observe pathological changes. In group B, the pH, buffer base (BB), base excess (BE), total carbon dioxide content (ctCO2), oxygen saturation of arterial blood (sO2), oxygen tension of arterial blood (pO2), serum sodium (Na+) concentration, lactate dehydrogenase (LDH) activity and total protein (TP) level were significantly reduced, and the carbon dioxide tension of arterial blood (pCO2), serum chloride (Cl−) concentration, serum total bilirubin (TBIL) level and alkaline phosphatase (ALP) activity were significantly increased compared with those in group A (P<0.05). In group C, the pH, BB, BE, sO2, pO2, hemoglobin (Hb) level, serum Na+ concentration, LDH activity and TP level were significantly reduced, and the pCO2, serum Cl− concentration, alanine transaminase activity, TBIL and urea levels were significantly increased (P<0.05) compared with those in group A. The Hb and ALP levels in group C were significantly lower than those in group B (P<0.05); and the TP, TBIL and urea levels in group C were significantly higher than those in group B (P<0.05). Pathological observation revealed that

  19. Single-exposure multiphoton fabrication of polygonized structures by an SLM-modulated Fresnel zone lens

    NASA Astrophysics Data System (ADS)

    Zhang, Chenchu; Hu, Yanlei; Li, Jiawen; Lao, Zhaoxin; Xu, Bing; Ni, Jincheng; Cai, Ze; Wu, Dong; Chu, Jiaru

    2016-03-01

    Recently, annular beams have been developed to rapidly fabricate microscope tubular structures via two-photon polymerization, but the distribution of the light field is limited to a ring pattern. Here a Fresnel lens is designed and applied to modulate the light field into a uniform quadrangle or hexagon shape with controllable diameters. By applying a spatial light modulator to load the phase information of the Fresnel lens, quadrangle and hexagon structures are achieved through single exposure of a femtosecond laser. A 3×6 array of structures is made within 9 s. Comparing with the conventional holographic processing, this method shows higher uniformity, high efficiency, better flexibility, and easy operation. The approach exhibited a promising prospect in rapidly fabricating structures such as tissue engineering scaffolds and variously shaped tubular arrays.

  20. Acute effects and exposure to organic compounds in road maintenance workers exposed to asphalt

    SciTech Connect

    Norseth, T.; Waage, J.; Dale, I. )

    1991-01-01

    Subjective symptoms and exposure to organic compounds were recorded in road repair and construction workers. Abnormal fatigue, reduced appetite, laryngeal/pharyngeal irritation, and eye irritation were recorded more often in such workers handling asphalt than in a corresponding reference group without asphalt exposure. Mean daily exposure to volatile compounds was only occasionally above 1 ppm. Mean exposure to asphalt fume was 0.358 mg/m3. There was no correlation between symptoms and total amount of volatile compounds, but a significant positive correlation was demonstrated between symptoms and some substances. The highest correlation was found for 1, 2, 4 trimethyl benzene. Symptoms increased with increasing asphalt temperature and with increasing concentrations of asphalt fumes. Amine addition did not increase the sum of symptoms, but soft asphalt seems to result in fewer symptoms than the harder types. Symptoms were not related to external factors like weather, traffic density, or specific working operations. As preventive measures, asphalt temperature should be kept below 150 degrees C, fume concentrations below 0.40 mg/m3, and if possible, the use of harder asphalt types which also require high temperatures should be avoided.

  1. EFFECT OF ROUTE AND PATTERN OF EXPOSURE ON THE PHARMACOKINETICS AND ACUTE HEPATOTOXICITY OF CARBON TETRACHLORIDE

    EPA Science Inventory

    The objectives of this study were to evaluate the influence of both route and pattern of exposure on the pharmacokinetics and target organ toxicity of a common VOC, carbon tetrachloride (CCl4). ale Sprague-Dawley rats, 325-275 g, inhaled 100 or 1,000 ppm CCl4 for 2 hr through a o...

  2. Acute effects of exposure to space radiation on CNS function and cognitive performance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    On exploratory class missions, such as a mission to Mars, astronauts will be exposed to types and doses of radiation (cosmic rays) that are not experienced in low earth orbit where the Space Shuttle and International Space Station operate. Exposure to cosmic rays produces changes in neuronal functi...

  3. Electrocardiographic and autonomic effects of acute particulate matter (PM) exposure in a rat model of cardiomyopathy

    EPA Science Inventory

    Human exposure to ambient PM from fossil-fuel emissions is linked to cardiovascular disease and death. This association strengthens in people with preexisting cardiac disease--especially heart failure (HF). Cardiomyopathy is the most common cause of heart failure. The mechanisms ...

  4. KIDNEY TOXICOGENOMICS OF ACUTE SODIUM AND POTASSIUM BROMATE EXPOSURE IN F344 MALE RAT

    EPA Science Inventory

    Bromate, used in both the food and cosmetics industry, is a drinking water disinfection by-product that is nephrotoxic and carcinogenic to rodents. To gain insight into the carcinogenic mechanism of action, identify possible biomarkers of exposure, and determine if the cation, po...

  5. Long-lasting transcriptional refractoriness triggered by a single exposure to 1-methyl-4-phenyl-1,2,3,6-tetrahydropyrimidine.

    PubMed

    Pattarini, R; Rong, Y; Shepherd, K R; Jiao, Y; Qu, C; Smeyne, R J; Morgan, J I

    2012-07-12

    Parkinson's disease (PD) is a progressive neurodegenerative disorder whose etiology is thought to have environmental (toxin) and genetic contributions. The neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyrimidine (MPTP) induces pathological features of PD including loss of dopaminergic neurons in the substantia nigra pars compacta (SNpc) and striatal dopamine (DA) depletion. We previously described the striatal transcriptional response following acute MPTP administration in MPTP-sensitive C57BL/6J mice. We identified three distinct phases: early (5h), intermediate (24h) and late (72h) and reported that the intermediate and late responses were absent in MPTP-resistant Swiss-Webster (SWR) mice. Here we show that C57BL/6J mice pre-treated with a single 40 mg/kg dose of MPTP and treated 9 days later with 4×20 mg/kg MPTP, display a striatal transcriptional response similar to that of MPTP-resistant SWR mice, i.e. a robust acute response but no intermediate or late response. Transcriptional refractoriness is dependent upon the dose of the priming challenge with as little as 10mg/kg MPTP being effective and can persist for more than 28 days. Priming of SWR mice has no effect on their response to subsequent challenge with MPTP. We also report that paraquat, another free radical producer, also elicits striatal transcriptional alterations but these are largely distinct from those triggered by MPTP. Paraquat-induced changes are also refractory to priming with paraquat. However neither paraquat nor MPTP elicits cross-attenuation. Thus exposure to specific toxins triggers distinct transcriptional responses in striatum that are influenced by prior exposure to the same toxin. The prolonged refractory period described here for MPTP could explain at the molecular level the reported discrepancies between different MPTP administration regimens and may have implications for our understanding of the relationship between environmental toxin exposure and PD. PMID:22542874

  6. [Retrospective Cytogenetic Dose Evaluation. I. Chromosome Aberration Levels in Remote Periods after Acute External Exposure in Different Situations].

    PubMed

    Nugs, V Yu; Khvostunov, I K; Goloub, E V; Kozlova, M G; Nadejina, N M; Galstian, I A

    2015-01-01

    Cytogenetic analysis of peripheral blood lymphocyte cultures of 22 persons was performed in remote terms after acute external γ-, γ-β- or γ-neutron irradiation as a result of various accidents using the classical me- thod. The initial dose estimates were obtained using physical calculations, the method of measuring the EPR signal in tooth enamel, according to haematological and/or cytogenetic parameters. The purpose of this study was to obtain evidence about the state of the lymphocyte chromosome apparatus of people approxi- mately 17-50 years after an accidental radiation exposure. In general, elevated levels of chromosome aberra- tions were detected. An average correlation was observed between the atypical chromosome frequency and absorbed dose. It is proposed to use the obtained results in the future to explore the possibility of retrospective dose evaluation on the basis of a special computer program. PMID:26601536

  7. Acute effects of benzene and cyclophosphamide exposure on cellular and humoral immunity of cotton rats, Sigmodon hispidus

    SciTech Connect

    McMurry, S.T.; Lochmiller, R.L.; Vestey, M.R.; Qualls, C.W. Jr.; Elangbam, C.S. )

    1991-06-01

    Many environmental pollutants are potent immunotoxicants with the capability of altering host resistance to pathogens and compromising overall immunological integrity. Because environmental contaminants typically occur as a diverse group of compounds that are difficult to individually identify, their hazardous potential is often difficult to study in the laboratory. Consequently, development of wild mammalian species as bioindicators of environmental contamination may provide an alterative approach to assessing the hazardous potential of immunotoxicants for both human and wildlife populations. The cotton rat (Sigmodon hispidus) is an excellent prospect as an in situ bioindicator of environmental contamination of terrestrial ecosystems. Recently, the authors initiated studies in their laboratory to develop a sensitive method to evaluate environmental immunotoxicity hazards to wildlife and humans. The present study was designed to test the sensitivity of selected humoral and cell-mediated immune response assays in the cotton rat to acute benzene and cyclophosphamide exposure which are known immunotoxicants.

  8. Osteosarcoma development following single inhalation exposure to americium-241 in beagle dogs

    SciTech Connect

    Gillett, N.A.; Hahn, F.F.; Mewhinney, J.A.; Muggenberg, B.A.

    1985-10-01

    Young, mature Beagle dogs underwent single inhalation exposure to respirable aerosols of SU AmO2 to determine the radiation dose distribution to tissues. The dogs were serially sacrificed to assess the clearance of SU Am from the lung, the rate of translocation to internal organs, the pattern of retention in the organs, and the rates and modes of excretion. Americium dioxide was relatively soluble in the lung, leading to the translocation of significant quantities of SU Am to bone and liver, thus delivering radiation doses to these tissues nearly equal to that received by the lung. Osteoblastic osteosarcomas developed in four dogs surviving more than 1000 days after exposure. Histologically, all of the osteosarcomas were associated with areas of radiation osteodystrophy characterized by bone infarction, peritrabecular new bone formation, marrow fibrosis, and microresorptive cavities. The retention and translocation of inhaled SU Am in dogs is similar to that of man, indicating that 241Am inhaled by humans may potentially result in significant risk of bone tumor development.

  9. A single-particle characterization of a mobile Versatile Aerosol Concentration Enrichment System for exposure studies

    PubMed Central

    Freney, Evelyn J; Heal, Mathew R; Donovan, Robert J; Mills, Nicholas L; Donaldson, Kenneth; Newby, David E; Fokkens, Paul HB; Cassee, Flemming R

    2006-01-01

    Background An Aerosol Time-of-Flight Mass Spectrometer (ATOFMS) was used to investigate the size and chemical composition of fine concentrated ambient particles (CAPs) in the size range 0.2–2.6 μm produced by a Versatile Aerosol Concentration Enrichment System (VACES) contained within the Mobile Ambient Particle Concentrator Exposure Laboratory (MAPCEL). The data were collected during a study of human exposure to CAPs, in Edinburgh (UK), in February-March 2004. The air flow prior to, and post, concentration in the VACES was sampled in turn into the ATOFMS, which provides simultaneous size and positive and negative mass spectral data on individual fine particles. Results The particle size distribution was unaltered by the concentrator over the size range 0.2–2.6 μm, with an average enrichment factor during this study of ~5 (after dilution of the final air stream). The mass spectra from single particles were objectively grouped into 20 clusters using the multivariate K-means algorithm and then further grouped manually, according to similarity in composition and time sequence, into 8 main clusters. The particle ensemble was dominated by pure and reacted sea salt and other coarse inorganic dusts (as a consequence of the prevailing maritime-source climatology during the study), with relatively minor contributions from carbonaceous and secondary material. Very minor variations in particle composition were noted pre- and post-particle concentration, but overall there was no evidence of any significant change in particle composition. Conclusion These results confirm, via single particle analysis, the preservation of the size distribution and chemical composition of fine ambient PM in the size range 0.2–2.6 μm after passage through the VACES concentration instrumentation. PMID:16723024

  10. Chemosensory irritations and pulmonary effects of acute exposure to emissions from oriented strand board.

    PubMed

    Gminski, Richard; Marutzky, Rainer; Kevekordes, Sebastian; Fuhrmann, Frank; Bürger, Werner; Hauschke, Dieter; Ebner, Winfried; Mersch-Sundermann, Volker

    2011-09-01

    Due to the reduction of air change rates in low-energy houses, the contribution to indoor air quality of volatile organic compounds (VOCs) emitting from oriented strand boards (OSB) has become increasingly important. The aim of this study was to evaluate sensory irritations, pulmonary effects and odor annoyance of emissions from OSB in healthy human volunteers compared to clean air. Twenty-four healthy non-smokers were exposed to clean air and OSB emissions for 2 h under controlled conditions in a 48 m(3) test chamber at three different time points: to fresh OSB panels and to the same panels after open storage for 2 and 8 weeks. Chemosensory irritation, exhaled nitric oxide (NO) concentration, eye blink frequency, lung function and subjective perception of irritation of eyes, nose and throat were examined before, during and after exposure. Additionally, olfactory perception was investigated. Total VOC exposure concentrations reached 8.9 ± 0.8 mg/m(3) for the fresh OSB panels. Emissions consisted predominantly of α-pinene, Δ(3)-carene and hexanal. Two-hour exposure to high VOC concentrations revealed no irritating or pulmonary effects. All the subjective ratings of discomfort were at a low level and the medians did not exceed the expression 'hardly at all.' Only the ratings for smell of emissions increased significantly during exposure in comparison to clean air. In conclusion, exposure of healthy volunteers to OSB emissions did not elicit sensory irritations or pulmonary effects up to a VOC concentration of about 9 mg/m(3). Sensory intensity of OSB emissions in the chamber air was rated as 'neutral to pleasant.' PMID:21071553

  11. Acute Atrazine Exposure has Lasting Effects on Chemosensory Responses to Food Odors in Crayfish (Orconectes virilis).

    PubMed

    Belanger, Rachelle M; Mooney, Lauren N; Nguyen, Hung M; Abraham, Noor K; Peters, Tyler J; Kana, Maria A; May, Lauren A

    2016-02-01

    The herbicide atrazine is known to impact negatively olfactory-mediated behaviors in aquatic animals. We have shown that atrazine exposure has deleterious effects on olfactory-mediated behavioral responses to food odors in crayfish; however, recovery of chemosensory abilities post-atrazine exposure has not been investigated. We examined whether crayfish (Orconectes virilis) recovered chemosensory abilities after a 96-h exposure to sublethal, environmentally relevant concentrations of 80 ppb (µg/L) atrazine. Following treatment, we analyzed the ability of the crayfish to locate a food source using a Y-maze with one arm containing fish-flavored gelatin and the other containing unflavored gelatin. We compared the time spent in the food arm of the Y-maze, near the food source, as well as moving and walking speed of control and atrazine-treated crayfish. We also compared the number of crayfish that handled the food source and the amount of food consumed. Following 24-, 48-, and 72-h recovery periods in fresh water, behavioral trials were repeated to determine if there was any observable recovery of chemosensory-mediated behaviors. Atrazine-treated crayfish spent less time in the food arm, at the odor source, and were less successful at finding the food odor source than control crayfish for all times tested. Additionally, atrazine-treated crayfish consumed less fish-flavored than control crayfish; however, treatment did not affect locomotion. Overall, we found that crayfish are not able to recover chemosensory abilities 72 h post-atrazine exposure. Because crayfish rely heavily on their chemosensory abilities to acquire food, the negative impacts of atrazine exposure could affect population size in areas where atrazine is heavily applied. PMID:26487338

  12. Combined exposure to simulated microgravity and acute or chronic radiation reduces neuronal network integrity and cell survival

    NASA Astrophysics Data System (ADS)

    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)

  13. Toxicological responses to acute mercury exposure for three species of Manila clam Ruditapes philippinarum by NMR-based metabolomics.

    PubMed

    Liu, Xiaoli; Zhang, Linbao; You, Liping; Cong, Ming; Zhao, Jianmin; Wu, Huifeng; Li, Chenghua; Liu, Dongyan; Yu, Junbao

    2011-03-01

    The Manila clam (Ruditapes philippinarum) has been considered a good sentinel species for metal pollution monitoring in estuarine tidal flats. Along the Bohai coast of China, there are dominantly distributed three species of clams (White, Liangdao Red and Zebra in Yantai population) endowed with distinct tolerances to environmental stressors. In this study, adductor muscle samples were collected from both control and acute mercury exposed White, Liangdao Red and Zebra clams, and the extracts were analyzed by NMR-based metabolomics to compare the metabolic profiles and responses to the acute mercury exposure to determine the most sensitive clam species capable of acting as abioindicator for heavy metal pollution monitoring. The major abundant metabolites in the White clam sample were branched-chain amino acids (leucine, isoleucine and valine), lactate, arginine, aspartate, acetylcholine, homarine and ATP/ADP, while the metabolite profile of Zebra clam sample comprised high levels of glutamine, acetoacetate, betaine, taurine and one unidentified metabolite. For the Liangdao Red clam sample, the metabolite profile relatively exhibited high amount of branched-chain amino acids, arginine, glutamate, succinate, acetylcholine, homarine and two unassigned metabolites. After 48h exposure of 20μgL(-1) Hg(2+), the metabolic profiles showed significant differences between three clam species, which included increased lactate, succinate, taurine, acetylcholine, betaine and homarine and decreased alanine, arginine, glutamine, glutamate, acetoacetate, glycine and ATP/ADP in White clam samples, and elevated succinate, taurine and acetylcholine, and declined glutamine, glycine, and aspartate in Liangdao Red clam samples, while the increased branched-chain amino acids, lactate, succinate, acetylcholine and homarine, and reduced alanine, acetoacetate, glycine and taurine were observed in the Zebra clam samples. Overall, our findings showed that White clams could be a preferable

  14. Longitudinal tracking of cytokines after acute exposure to tuberculosis: association of distinct cytokine patterns with protection and disease development.

    PubMed

    Hussain, Rabia; Talat, Najeeha; Shahid, Firdaus; Dawood, Ghaffar

    2007-12-01

    Household contacts (HCs) of patients with tuberculosis (TB) are at higher risk of infection as well as the development of active disease. Longitudinal tracking of antigen-specific cytokines after acute exposure may significantly advance our understanding of the dynamic changes in cytokine patterns associated with disease establishment. To achieve this objective, we carried out a prospective cohort study with healthy HCs after exposure to TB. The patterns of cytokines (gamma interferon [IFN-gamma] and interleukin 10 [IL-10]) in response to mycobacterial antigens (culture filtrate [CF] proteins) and nonspecific mitogens (phytohemagglutinin [PHA] and lipopolysaccharide [LPS]) were assessed at 0, 6, 12, and 24 months after exposure. Seven of 109 (6.4%) HCs developed active disease. Six of the seven individuals were females, and active disease developed between 12 and 15 months after exposure in 5/20 families. The most significant findings were the exponential increases ( approximately 1,000-fold) in both the CF protein- and the PHA- or LPS-induced IFN-gamma/IL-10 ratio in healthy HCs (n = 26), which peaked at 12 months, compared to the levels in HCs who developed disease (n = 7), in whom relatively flat responses were observed during the 24-month period. Linear trends for 0 to 12 and 0 to 24 months for the CF protein-induced IFN-gamma/IL-10 ratio showed significant differences between the two groups, as determined by the use of the Mantel extension test for chi(2) analysis (odds ratio = 0.45; 95% confidence interval = 0.295 to 0.685; P = 0.0002). Our results strongly suggest that the magnitude of the IFN-gamma/IL-10 ratio at 12 months after exposure may be a critical determinant in the resolution of infection. These studies provide new insights into the cytokine responses associated with disease establishment or the resolution of infection after natural exposure to TB and have implications for TB control programs as well vaccine efficacy studies. PMID:17928427

  15. Longitudinal Tracking of Cytokines after Acute Exposure to Tuberculosis: Association of Distinct Cytokine Patterns with Protection and Disease Development▿

    PubMed Central

    Hussain, Rabia; Talat, Najeeha; Shahid, Firdaus; Dawood, Ghaffar

    2007-01-01

    Household contacts (HCs) of patients with tuberculosis (TB) are at higher risk of infection as well as the development of active disease. Longitudinal tracking of antigen-specific cytokines after acute exposure may significantly advance our understanding of the dynamic changes in cytokine patterns associated with disease establishment. To achieve this objective, we carried out a prospective cohort study with healthy HCs after exposure to TB. The patterns of cytokines (gamma interferon [IFN-γ] and interleukin 10 [IL-10]) in response to mycobacterial antigens (culture filtrate [CF] proteins) and nonspecific mitogens (phytohemagglutinin [PHA] and lipopolysaccharide [LPS]) were assessed at 0, 6, 12, and 24 months after exposure. Seven of 109 (6.4%) HCs developed active disease. Six of the seven individuals were females, and active disease developed between 12 and 15 months after exposure in 5/20 families. The most significant findings were the exponential increases (∼1,000-fold) in both the CF protein- and the PHA- or LPS-induced IFN-γ/IL-10 ratio in healthy HCs (n = 26), which peaked at 12 months, compared to the levels in HCs who developed disease (n = 7), in whom relatively flat responses were observed during the 24-month period. Linear trends for 0 to 12 and 0 to 24 months for the CF protein-induced IFN-γ/IL-10 ratio showed significant differences between the two groups, as determined by the use of the Mantel extension test for χ2 analysis (odds ratio = 0.45; 95% confidence interval = 0.295 to 0.685; P = 0.0002). Our results strongly suggest that the magnitude of the IFN-γ/IL-10 ratio at 12 months after exposure may be a critical determinant in the resolution of infection. These studies provide new insights into the cytokine responses associated with disease establishment or the resolution of infection after natural exposure to TB and have implications for TB control programs as well vaccine efficacy studies. PMID:17928427

  16. Induction of genomic instability after an acute whole-body exposure of mice to 56Fe ions

    NASA Astrophysics Data System (ADS)

    Rithidech, Kanokporn; Supanpaiboon, Wisa; Whorton, Elbert

    Different types of galactic cosmic rays (GCR) are present in space and have large mass and energy (HZE particles). Among these, stripped 56 Fe ions are of major concern. Although HZE particles are approximately 1% of GCR, their contribution to health risk could be significant because of (1) their high linear energy transfer (LET) resulting in a larger amount of energy being deposited in the hit cells, and (2) the lack of information on the effectiveness of these particles in cancer induction. To better protect astronauts in space environments, it is essential that we improve our understanding of the 56 Fe-ion-induced damage associated with the increased risk of late occurring diseases (such as cancer). It has been well established that acute myeloid leukemia (AML) is one of the major malignancies associated with exposure to ionizing radiation in both human beings and in mice. It is therefore one of the most important cancers related to space flights. For these reasons, it is important to investigate 56 Fe ion-induced damage in in vivo systems, especially in those cells that are known to be at risk for health problems associated with radiation, such as hematopoietic cells, the known target cell for radiation-induced leukemia. Since in vivo studies of humans are not possible, animal studies are critically important. It has been widely suggested that elevation of delayed chromosomal damage (normally known as genomic instability) is associated with cancer risk. We therefore determined dose-response relationships for the frequencies of micronuclei (MN) in mouse blood erythrocytes as a measure of both initial radiation damage and the induction of genomic instability. The frequencies of MN were measured in mature normochromatic-erythrocytes (MN-NCEs) and immature polychromatic-erythrocytes (MN-PCEs). These measurements were made as a function of radiation dose, radiation quality, time after irradiation and the genetic background of exposed mice. Blood samples were

  17. Identification of Novel Single Nucleotide Polymorphisms Associated with Acute Respiratory Distress Syndrome by Exome-Seq

    PubMed Central

    Shortt, Katherine; Chaudhary, Suman; Grigoryev, Dmitry; Heruth, Daniel P.; Venkitachalam, Lakshmi; Zhang, Li Q.; Ye, Shui Q.

    2014-01-01

    Acute respiratory distress syndrome (ARDS) is a lung condition characterized by impaired gas exchange with systemic release of inflammatory mediators, causing pulmonary inflammation, vascular leak and hypoxemia. Existing biomarkers have limited effectiveness as diagnostic and therapeutic targets. To identify disease-associating variants in ARDS patients, whole-exome sequencing was performed on 96 ARDS patients, detecting 1,382,399 SNPs. By comparing these exome data to those of the 1000 Genomes Project, we identified a number of single nucleotide polymorphisms (SNP) which are potentially associated with ARDS. 50,190SNPs were found in all case subgroups and controls, of which89 SNPs were associated with susceptibility. We validated three SNPs (rs78142040, rs9605146 and rs3848719) in additional ARDS patients to substantiate their associations with susceptibility, severity and outcome of ARDS. rs78142040 (C>T) occurs within a histone mark (intron 6) of the Arylsulfatase D gene. rs9605146 (G>A) causes a deleterious coding change (proline to leucine) in the XK, Kell blood group complex subunit-related family, member 3 gene. rs3848719 (G>A) is a synonymous SNP in the Zinc-Finger/Leucine-Zipper Co-Transducer NIF1 gene. rs78142040, rs9605146, and rs3848719 are associated significantly with susceptibility to ARDS. rs3848719 is associated with APACHE II score quartile. rs78142040 is associated with 60-day mortality in the overall ARDS patient population. Exome-seq is a powerful tool to identify potential new biomarkers for ARDS. We selectively validated three SNPs which have not been previously associated with ARDS and represent potential new genetic biomarkers for ARDS. Additional validation in larger patient populations and further exploration of underlying molecular mechanisms are warranted. PMID:25372662

  18. Single acute stress-induced progesterone and ovariectomy alter cardiomyocyte contractile function in female rats

    PubMed Central

    Kalász, Judit; Tóth, Enikő Pásztor; Bódi, Beáta; Fagyas, Miklós; Tóth, Attila; Pal, Bhattoa Harjit; Vári, Sándor G.; Balog, Marta; Blažetić, Senka; Heffer, Marija; Papp, Zoltán; Borbély, Attila

    2014-01-01

    Aim To assess how ovarian-derived sex hormones (in particular progesterone) modify the effects of single acute stress on the mechanical and biochemical properties of left ventricular cardiomyocytes in the rat. Methods Non-ovariectomized (control, n = 8) and ovariectomized (OVX, n = 8) female rats were kept under normal conditions or were exposed to stress (control-S, n = 8 and OVX-S, n = 8). Serum progesterone levels were measured using a chemiluminescent immunoassay. Left ventricular myocardial samples were used for isometric force measurements and protein analysis. Ca2+-dependent active force (Factive), Ca2+-independent passive force (Fpassive), and Ca2+-sensitivity of force production were determined in single, mechanically isolated, permeabilized cardiomyocytes. Stress- and ovariectomy-induced alterations in myofilament proteins (myosin-binding protein C [MyBP-C], troponin I [TnI], and titin) were analyzed by sodium dodecyl sulfate gel electrophoresis using protein and phosphoprotein stainings. Results Serum progesterone levels were significantly increased in stressed rats (control-S, 35.6 ± 4.8 ng/mL and OVX-S, 21.9 ± 4.0 ng/mL) compared to control (10 ± 2.9 ng/mL) and OVX (2.8 ± 0.5 ng/mL) groups. Factive was higher in the OVX groups (OVX, 25.9 ± 3.4 kN/m2 and OVX-S, 26.3 ± 3.0 kN/m2) than in control groups (control, 16.4 ± 1.2 kN/m2 and control-S, 14.4 ± 0.9 kN/m2). Regarding the potential molecular mechanisms, Factive correlated with MyBP-C phosphorylation, while myofilament Ca2+-sensitivity inversely correlated with serum progesterone levels when the mean values were plotted for all animal groups. Fpassive was unaffected by any treatment. Conclusion Stress increases ovary-independent synthesis and release of progesterone, which may regulate Ca2+-sensitivity of force production in left ventricular cardiomyocytes. Stress and female hormones differently alter Ca2+-dependent cardiomyocyte contractile

  19. Association of short-term exposure to fine particulate matter and nitrogen dioxide with acute cardiovascular effects.

    PubMed

    Wu, Chang-Fu; Shen, Fu-Hui; Li, Ya-Ru; Tsao, Tsung-Ming; Tsai, Ming-Jer; Chen, Chu-Chih; Hwang, Jing-Shiang; Hsu, Sandy Huey-Jen; Chao, Hsing; Chuang, Kai-Jen; Chou, Charles C K; Wang, Ya-Nan; Ho, Chi-Chang; Su, Ta-Chen

    2016-11-01

    This study evaluated whether exposure to fine particulate matter (PM2.5) and nitrogen dioxide (NO2) is associated with cardiovascular effects by examining a panel of 89 healthy subjects in Taipei, Taiwan. The subjects received two health examinations approximately 8months apart in 2013. Brachial-ankle pulse wave velocity (baPWV), a physiological indicator of arterial stiffness, and high-sensitivity C-reactive protein (hsCRP), a biomarker of vascular inflammations, were measured during each examination. Two exposure assessment methods were used for estimating the subjects' exposure to PM2.5 and NO2. The first method involved constructing daily land use regression (LUR) models according to measurements collected at ambient air quality monitoring stations. The second method required combining the LUR estimates with indoor monitoring data at the workplace of the subjects. Linear mixed models were used to examine the association between the exposure estimates and health outcomes. The results showed that a 10-μg/m(3) increase in PM2.5 concentration at a 1-day lag was associated with 2.1% (95% confidence interval: 0.7%-3.6%) and 2.4% (0.8%-4.0%) increases in baPWV based on the two exposure assessment methods, whereas no significant association was observed for NO2. The significant effects of PM2.5 remained in the two-pollutant models. By contrast, NO2, but not PM2.5, was significantly associated with increased hsCRP levels (16.0%-37.3% in single-pollutant models and 26.4%-44.6% in two-pollutant models, per 10-ppb increase in NO2). In conclusion, arterial stiffness might be more sensitive to short-term PM2.5 exposure than is inflammation. PMID:27344119

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

    SciTech Connect

    Fabrikant, J.I.

    1981-05-01

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

  1. Acute neurobehavioral effects in rats from exposure to HFC 134a or CFC 12.

    PubMed

    Ritchie, G D; Kimmel, E C; Bowen, L E; Reboulet, J E; Rossi, J

    2001-04-01

    1,1,1,2-Tetrafluoroethane (HFC 134a), a chlorine-free hydrofluoroalkane, is internationally replacing billions of pounds of dichlorodifluoromethane (CFC 12) for coolant, refrigerant and aerosol propellant applications. The ALC50 for HFC 134a in rats is 567,000 ppm for 4 h; its potential for cardiac epinephrine sensitization in beagle dogs is acceptable (75,000 ppm); and its capacity to induce carcinogenicity or developmental disorders in animals is minimal. HFC 134a, with a serum half life estimated at 4-11 min, has been accepted for use as a propellant in metered-dose inhalant products, implying a low human toxicity risk from periodic brief exposures. There has been little published human or animal research evaluating possible neurobehavioral toxicity from longer HFC 134a exposures, as may be expected to occur in operational scenarios. In this study, male Wistar rats were exposed to various concentrations of HFC 134a or CFC 12 for up to 30 min while performing in either a rotarod/motorized running wheel apparatus or in an operant chamber The relative neurobehavioral toxicity of CFC 12 and its ozone-depleting substance replacement HFC 134a was assessed by comparing both gross motor system incapacitation and more subtle changes in ability to perform an operant discrimination task. It was shown that exposure to HFC 134a or CFC 12 concentrations from 40,000 to 470,000 ppm, for up to 30 min, induced neurobehavioral deficits in every subject, ranging from reduced operant efficiency to apparent anesthesia. For neurobehavioral endpoints examined in these experiments, HFC 134a inhalation was shown to induce deficits more rapidly, and at lower concentrations when compared to CFC 12 exposure. PMID:11405255

  2. Physiology in medicine: acute altitude exposure in patients with pulmonary and cardiovascular disease.

    PubMed

    Seccombe, Leigh M; Peters, Matthew J

    2014-03-01

    Travel is more affordable and improved high-altitude airports, railways, and roads allow rapid access to altitude destinations without acclimatization. The physiology of exposure to altitude has been extensively described in healthy individuals; however, there is a paucity of data pertaining to those who have reduced reserve. This Physiology in Medicine article discusses the physiological considerations relevant to the safe travel to altitude and by commercial aircraft in patients with pulmonary and/or cardiac disease. PMID:24371015

  3. CHOLINE AMELIORATES DEFICITS IN BALANCE CAUSED BY ACUTE NEONATAL ETHANOL EXPOSURE

    PubMed Central

    Bearer, Cynthia F.; Wellmann, Kristen A.; Tang, Ningfeng; He, Min; Mooney, Sandra M.

    2015-01-01

    Fetal alcohol spectrum disorder (FASD) is estimated to occur in 1% of all live births. The developing cerebellum is vulnerable to the toxic effects of alcohol. People with FASD have cerebellar hypoplasia and developmental deficits associated with cerebellar injury. Choline is an essential nutrient but many diets in the USA are choline deficient. In rats, choline given with or following alcohol exposure reduces many alcohol-induced neurobehavioral deficits, but not those associated with cerebellar function. Our objective was to determine if choline supplementation prior to alcohol exposure would ameliorate the impact of ethanol on a cerebellar-associated behavioral test in mice. Pregnant C57Bl6/J mice were maintained on a choline deficient diet from embryonic day 4.5. On postnatal day 1 (P1), pups were assigned to one of 8 treatment groups: choline (C) or saline (S) pre-treatment from P1-5, ethanol (6 g/kg) or Intralipid® on P5, C or S post-treatment from P6-20. On P30, balance and coordination were tested using the dowel crossing test. Overall, there was a significant effect of treatment and females crossed longer distances than males. Ethanol exposure significantly reduced the total distance crossed. Choline pre-treatment increased the distance crossed by males, and both pre- and post-treatment with choline significantly increased total distance crossed for females and males. There was no effect of choline on Intralipid®-exposed animals. This is the first study to show that choline ameliorates ethanol-induced effects on balance and coordination when given before ethanol exposure. Choline fortification of common foodstuffs may reduce the effects of alcohol. PMID:26085462

  4. Pulmonary effects of acute exposure to degradation products of sulphur hexafluoride during electrical cable repair work.

    PubMed Central

    Kraut, A; Lilis, R

    1990-01-01

    Six electrical workers accidentally exposed to degradation products of sulphur hexafluoride (SF6) during electrical repair work were followed up for one year. One degradation product, sulphur tetrafluoride (SF4), was identified from worksite measurements. Unprotected exposure in an underground enclosed space occurred for six hours over a 12 hour period. Initial symptoms included shortness of breath, chest tightness, productive cough, nose and eye irritation, headache, fatigue, nausea, and vomiting. Symptoms subsided when exposure was interrupted during attempts to identify the cause of the problem. Although exposure ended after several hours, four workers remained symptomatic for between one week and one month. Pulmonary radiographic abnormalities included several discrete areas of transitory platelike atelectasis in one worker, and a slight diffuse infiltrate in the left lower lobe of another. One worker showed transient obstructive changes in tests of pulmonary function. Examination at follow up after one year showed no persistent abnormalities. Preliminary data from this paper were presented at the VIIth international pneumoconioses conference. Pittsburgh, PA, August 1988. PMID:2271390

  5. Estimation of potential health effects from acute exposure to hydrogen fluoride using a "benchmark dose" approach.

    PubMed

    Alexeeff, G V; Lewis, D C; Ragle, N L

    1993-02-01

    Communities across the United States are examining the manufacture, use, transport, and storage of hydrogen fluoride (HF) near residential areas as a consequence of a major release of HF in Texas in 1987. Reference exposure levels for routine and accidental HF emissions are calculated using existing animal and human data. The approach employs a log-probit extrapolation of concentration-response data to the 95% lower confidence limit on the toxic concentration producing a "benchmark dose" of 1% response (TC01), called a practical threshold. Species-specific and chemical-specific adjustment factors are applied to develop exposure levels applicable to the general public. Using this method, the 1-hr reference exposure level to protect the public against any irritation from a routine emission (REL-1) is 0.7 ppm and the level to protect against severe irritation from a once-in-a-lifetime (REL-2) release is 2 ppm. This approach is compared to a modified "uncertainty factor" approach. PMID:8451461

  6. Acute exposure to hair bleach causes airway hyperresponsiveness in a rabbit model.

    PubMed

    Mensing, T; Marek, W; Raulf-Heimsoth, M; Baur, X

    1998-12-01

    Ammonium persulphate (APS) and hydrogen peroxide (H2O2) are used as oxidants in many industrial processes and are the main constituents of standard hair bleaching products. In a previous study, it was demonstrated that aerosols of APS induce alterations in airway responsiveness. The present study examined whether exposure for 4 h to a hair bleach composition (containing APS, potassium persulphate and H2O2) or H2O2 could induce airway hyperresponsiveness and/or an obstructive ventilation pattern in a rabbit model. Exposure to the aerosols altered neither baseline airway resistance, dynamic elastance, slope of inspiratory pressure generation nor arterial blood pressure and blood gas measurements. Similarly to APS, hair bleach aerosols containing > or =10.9 mg x m(-3) persulphate (ammonium and potassium salt) in air and > or =1.36 mg x m(-3) H2O2 in air caused airway hyperresponsiveness to acetylcholine after 4 h of exposure. Aerosolized H2O2 (> or =37 mg x m(-3) in air) did not influence airway responsiveness to acetylcholine. The results demonstrate that hair bleaching products containing persulphates dissolved in H2O2 cause airway hyperresponsiveness to acetylcholine in rabbits. PMID:9877493

  7. Single dose rasburicase in the management of tumor lysis syndrome in childhood acute lymphoblastic leukemia: A case series

    PubMed Central

    Latha, S. M.; Krishnaprasadh, D.; Murugapriya, P.; Scott, J. X.

    2015-01-01

    Tumor lysis syndrome (TLS) occurs in malignancies with high proliferative potential and tumor burden, such as lymphomas and leukemias. TLS syndrome is an oncologic emergency, requiring prompt intervention. The metabolic derangements cause acute kidney failure and may lead to cardiac arrhythmias, seizures, and death. With the advent of rasburicase, a recombinant urate oxidase, there has been a decline in the TLS-mediated renal failure and the need for dialysis. The recommended regimen and doses pose a heavy financial burden for patients in developing countries like India. With data and studies proving a similar efficacy for the reduced dose and lesser number of rasburicase, we report here a case series of seven children with acute leukemias, whose TLS was managed by a single dose of rasburicase. A retrospective analysis of case records of seven children with acute lymphoblastic leukemia and TLS, admitted to our Pediatric Oncology Unit of our Hospital between the period 2011 and 2013, was done. All our patients responded to a single dose, indicating that in appropriately monitored patients, single dose followed by as-needed dosing can be cost-saving. PMID:25838646