Gut-derived ammonia contributes to alcohol-related fatty liver development via facilitating ethanol metabolism and provoking ATF4-dependent de novo lipogenesis activation.

BACKGROUND & AIMS: Dysbiosis contributes to alcohol-associated liver disease (ALD); however, the precise mechanisms remain elusive. Given the critical role of the gut microbiota in ammonia production, we herein aim to investigate whether and how gut-derived ammonia contributes to ALD. METHODS: Blood samples were collected from human subjects with/without alcohol drinking. Mice were exposed to the Lieber-DeCarli isocaloric control or ethanol-containing diets with and without rifaximin (a nonabsorbable antibiotic clinically used for lowering gut ammonia production) supplementation for five weeks. Both in vitro (NH4Cl exposure of AML12 hepatocytes) and in vivo (urease administration for 5 days in mice) hyperammonemia models were employed. RNA sequencing and fecal amplicon sequencing were performed. Ammonia and triglyceride concentrations were measured. The gene and protein expression of enzymes involved in multiple pathways were measured. RESULTS: Chronic alcohol consumption causes hyperammonemia in both mice and human subjects. In healthy livers and hepatocytes, ammonia exposure upregulates the expression of urea cycle genes, elevates hepatic de novo lipogenesis (DNL), and increases fat accumulation. Intriguingly, ammonia promotes ethanol catabolism and acetyl-CoA formation, which, together with ammonia, synergistically facilitates intracellular fat accumulation in hepatocytes. Mechanistic investigations uncovered that ATF4 activation, as a result of ER stress induction and general control nonderepressible 2 activation, plays a central role in ammonia-provoked DNL elevation. Rifaximin ameliorates ALD pathologies in mice, concomitant with blunted hepatic ER stress induction, ATF4 activation, and DNL activation. CONCLUSIONS: An overproduction of ammonia by gut microbiota, synergistically interacting with ethanol, is a significant contributor to ALD pathologies.

Evaluation of human vulnerability and toxic effects of chronic and acute occupational exposure to ammonia: A case study in an ice factory.

BACKGROUND: The hazardous material release has frequently occurred worldwide. As a respiratory stimulant and a toxic substance, ammonia has numerous adverse effects on human health. OBJECTIVE: The purpose of this study was to evaluate the human vulnerability and toxic effects of both chronic and acute respiratory exposure to ammonia. METHODS: This study was conducted in an ice factory. Ammonia reservoirs were selected as the danger center. The scenarios were evaluated from the perspective of the worst-case. The Emergency Response Planning Guidelines 1-3 was used to predict the dangerous concentrations in acute exposure. The probability of human vulnerability was estimated using the Probit model. PHAST 7.2 software was used to model consequences. As a measure of chronic exposure to ammonia, NMAM 6016 was used. A respiratory symptom questionnaire developed by the American Thoracic Society was used for collecting respiratory symptom histories. RESULTS: The ERPG3 level or concentration of 750 ppm was found at a distance of 617.71 and 411.01 meters from tanks, respectively, as a result of a rupture in reservoir 1 over a period of two halves of the year. It was found that the highest probit values for tank 2 at distances of zero, 25, 50, 75, 100, 125, and 150 meters were 9.55, 5.92, 5.47, 4.82, 4.23, 3.56 and 2.96, respectively. The prevalence of pulmonary symptoms, which include coughing, dyspnea, phlegm, and wheezing, was 28%, 19%, 15%, and 26% in the chronic exposure group. CONCLUSION: In the event that an ammonia reservoir ruptures catastrophically, it may cause human injury at ERPG-2 or ERPG-3 levels. Results revealed that exposure to this substance can impose many pulmonary symptoms on the respiratory system of workers in industries. In order to reduce the vulnerability of humans to potential release scenarios, control measures must be implemented. Also, preventive and mitigation measures can be designed to enhance safety and resilience against the release of hazardous materials.

Indole-3-carbinol ameliorated the thioacetamide-induced hepatic encephalopathy in rats.

Indole-3-carbinol (I3C) is reported to have hepatic and neuroprotective properties. However, the I3C role in the protection of the liver and brain in the pathological condition of hepatic encephalopathy has not been investigated. Therefore, in the present study, we have assessed the hepatic and neuroprotective roles of I3C against thioacetamide (TAA)- induced hepatic encephalopathy in Wistar rats. TAA (300 mg/kg) was intraperitoneally administered to Wistar rats to induce hepatic encephalopathy. The elevated levels of ammonia in the blood, liver, and brain were substantially lowered by I3C treatment (25, 50, and 100 mg/kg, oral, 7 days). I3C significantly ameliorated the TAA-induced liver dysfunction by decreasing the alanine transaminase, aspartate transaminase, and alkaline phosphatase enzymes and reduced the elevated cytochrome P4502E1 (CYP2E1) activity in the liver and brain. Further, I3C alleviated mitochondrial dysfunction and oxidative stress in the brain. I3C treatment improved the anti-inflammatory cytokine interleukin (IL)- 10 while reducing inflammatory cytokines such as tumor necrosis factor-1 and IL-6 in hepatic encephalopathy rats. I3C reduced the levels of apoptotic indicators mediated by the mitochondria, including cytochrome c, caspase 9, and caspase 3. Concurrently, I3C mitigated the liver and brain histological abnormalities in hepatic encephalopathy rats. Therefore, the present study concluded that the I3C protected the liver and brain from TAA-induced hepatic encephalopathy injury by inhibiting CYP2E1 enzyme activity and decreasing ammonia, oxidative stress, inflammation, and apoptosis. The present study provides preclinical validation of I3C use as hepatic and neuroprotective for hepatic encephalopathy management.

Effect of Hardwood Dust and Ammonia Gas on the Respiratory Integrity of Broiler Chickens.

Dust and ammonia gas (NH3) are two of the most abundant pollutants suspended in the air of poultry houses. Chronic inhalation of poultry dust and NH3 causes damage to the airways and reduces performance in broilers. Poultry dust is a mixture of organic and inorganic matter from feed, bedding material, manure, feathers, skin debris, and microorganisms. Thus, the composition and concentration of poultry dust vary among farms. This study proposes a model to assess the individual effect of a defined fraction of poultry dust derived from bedding material (wood dust) and its effects, alone or combined with NH3, on the performance and respiratory integrity of broilers. Ninety-six, 1-day-old broilers were randomly divided into groups of 24 and placed into four controlled environment chambers to continuously receive one of four treatments: 1) negative control; 2) exposure to airborne red oak wood dust at a concentration of 7.5 × 106 particles/m3 (particulate matter5.0); 3) exposure to 50 parts per million (ppm) of NH3; and 4) exposure to airborne red oak wood dust and 50 ppm of NH3. On day 43, all birds were weighed and euthanized. Performance data were recorded. Tissue samples were collected from six birds per treatment. Histologic evaluations of the nasal turbinates, trachea, and lungs were conducted. Histologic lesion scores (0 to 3) were assigned, and tracheal mucosal thickness was measured. No significant differences among treatments were found in body weight (P = 0.066), tracheal mucosal thickness (P = 0.593), or tracheal lesion score (P = 0.07). The average nasal turbinate lesion scores were higher in the wood and wood + ammonia treatments compared with the control (P = 0.015). The lung lesion scores were higher (P = 0.004) in all treatment groups compared with the control. In conclusion, chronic exposure to red oak wood dust, alone or in combination with NH3, induced important inflammatory damage to portions of the respiratory system of broilers; however, no significant effects on performance were observed.

Efecto del polvo de madera dura y el gas amoníaco en la integridad respiratoria de pollos de engorde. El polvo y el gas amoníaco (NH3) son dos de los contaminantes más abundantes suspendidos en el aire de las casetas avícolas. La inhalación crónica de polvo en casetas avícolas y de NH3 provoca daños en las vías respiratorias y reduce el rendimiento de los pollos de engorde. El polvo de aves de corral es una mezcla de materia orgánica e inorgánica procedente del alimento, material de cama, estiércol, plumas, restos de piel y microorganismos. Por lo tanto, la composición y concentración del polvo de las aves de corral varía entre granjas. Este estudio propone un modelo para evaluar el efecto individual de una fracción definida de polvo avícola derivado del material de cama (polvo de madera) y sus efectos, solos o combinados con NH3, sobre el rendimiento y la integridad respiratoria de los pollos de engorde. Noventa y seis pollos de engorde de un día de edad se distribuyeron aleatoriamente en grupos de 24 y se colocaron en cuatro cámaras de ambiente controlado para recibir continuamente uno de los cuatro tratamientos: 1) control negativo; 2) exposición a polvo de madera de roble rojo en el aire a una concentración de 7.5 × 106 partículas/m3 (material particulado5.0); 3) exposición a 50 partes por millón (ppm) de NH3; y 4) exposición a polvo de madera de roble rojo en el aire y 50 ppm de NH3. Durante el día 43, todas las aves fueron pesadas y se les practicó la eutanasia. Se registraron los datos de rendimiento. Se recogieron muestras de tejido de seis aves por tratamiento. Se realizaron evaluaciones histológicas de los cornetes nasales, la tráquea y los pulmones. Se asignaron puntuaciones de lesiones histológicas (0 a 3) y se midió el espesor de la mucosa traqueal. No se encontraron diferencias significativas entre los tratamientos en el peso corporal (P = 0.066), el grosor de la mucosa traqueal (P = 0.593) o la puntuación de la lesión traqueal (P = 0.07). Las puntuaciones medias de las lesiones de los cornetes nasales fueron más altas en los tratamientos con madera y madera + amoníaco en comparación con el control (P = 0.015). Las puntuaciones de lesiones pulmonares fueron más altas (P = 0.004) en todos los grupos de tratamiento en comparación con el control. En conclusión, la exposición crónica al polvo de madera de roble rojo, solo o en combinación con NH3, indujo un daño inflamatorio importante en partes del sistema respiratorio de los pollos de engorde; sin embargo, no se observaron efectos significativos en el rendimiento.

Inhibition of Autotaxin Ameliorates LPA-Mediated Neuroinflammation and Alleviates Neurological Dysfunction in Acute Hepatic Encephalopathy.

Growing evidence suggests an essential role of neuroinflammation in behavioral abnormalities associated with hepatic encephalopathy (HE). Here, we report the involvement of autotaxin-lysophosphatidic acid (LPA) signaling in HE's pathogenesis. We demonstrate that the autotaxin (ATX) inhibitor PF-8380 attenuates neuroinflammation and improves neurological dysfunction in the mouse model of HE. In the thioacetamide (TAA)-induced model of HE, we found a twofold increase in the levels of ammonia in the brain and in plasma along with a significant change in HE-related behavioral parameters. Mice with HE show an increased brain weight, increased levels of tumor necrosis factor-α (TNF-α), IL-1ß (interleukin-1ß), interleukin-6 (IL-6), and LPA 18:0 in the cerebral cortex and hippocampus, and increased levels of LPA 18:0 in plasma. Treatment with the autotaxin inhibitor (ATXi) did not affect liver injury, as we observed no change in liver function markers including aspartate aminotransferase (AST), alanine aminotransferase (ALT), and total bilirubin (TBIL) and no change in ammonia levels in the brain and plasma. However, ATXi treatment significantly ameliorated the neuroinflammation, reduced the levels of LPA 18:0 in the cerebral cortex and hippocampus in the brain and plasma, and reduced brain edema and the levels of IL1ß, IL-6, and TNF-α. The neurobehavioral symptoms for HE such as the cognitive and motor function deficit and overall clinical grading score were significantly improved in ATXi-treated mice. Mouse astrocytes and microglia stimulated with NH4CL with or without ATXi showed significant attenuation of oxidative stress and the neuroinflammatory effect of NH4CL in ATXi-treated cells.

Effect of Cigarette Constituent Messages With Engagement Text on Intention to Quit Smoking Among Adults Who Smoke Cigarettes: A Randomized Clinical Trial.

Importance: The US Food and Drug Administration (FDA) is required to communicate the risks of tobacco constituents to the public. Few studies have addressed how FDA media campaigns can effectively communicate about cigarette smoke constituents. Objective: To examine whether messages about cigarette smoke constituents are effective in reducing smoking intentions and behaviors among adults who smoke. Design, Setting, and Participants: This randomized clinical trial enrolled participants who were aged between 18 and 65 years, were English speakers, were living in the United States, and who smoked at least 100 cigarettes during their lifetime and now smoked every day or some days. Participants received daily messages via email for 15 days. Participants were randomized to 1 of 2 message conditions or a control group and reported their previous-day smoking behaviors daily. Follow-up surveys were conducted on days 16 and 32. Data were collected from June 2017 to April 2018 and analyzed from April to September 2018. Interventions: The 3 groups were (1) constituent plus engagement messages (eg, "Cigarette smoke contains arsenic. This causes heart damage.") that included the FDA as the source and engagement text (eg, "Within 3 months of quitting, your heart and lungs work better. Ready to be tobacco free? You can quit. For free nicotine replacement, call 1-800-QUIT-NOW"); (2) constituent-only messages that did not list the FDA as the source or include engagement text; and (3) a control condition with messages about littering cigarette butts. Main Outcomes and Measures: The primary outcome was the change in quit intentions (range, 1-4, with higher scores indicating stronger intentions) from pretest to day 16. Secondary outcome measures included daily smoking behaviors and quit attempts. Results: A total of 789 participants (mean [SD] age, 43.4 [12.9] years; 483 [61.2%] women; 578 [73.3%] White; 717 [90.9%] non-Hispanic) were included in the study. The mean (SD) quit intention score was 2.5 (0.9) at pretest. Mean (SE) change in quit intention score from pretest to day 16 was 0.19 (0.07) points higher in the constituent plus engagement condition than in the control condition (P = .005) and 0.23 (0.07) points higher in the constituent-only condition compared with the control condition (P = .001). Participant reports of cigarettes smoked, forgone, and butted out were similar across study conditions at baseline and did not differ significantly at days 16 and 32 across study conditions. Viewing more messages was associated with an estimated decrease of 0.15 (SE, 0.01) cigarettes smoked per day per message viewed overall across conditions. Conclusions and Relevance: To our knowledge, this is the first longitudinal test of cigarette constituent campaign messages in a national sample of adults who currently smoke. Messages about cigarette smoke constituents, with or without engagement text and source information, increased participants' intentions to quit, lending support to FDA efforts to educate consumers about such constituents. Trial Registration: ClinicalTrials.gov Identifier: NCT03339206.

The nuclear factor kappa B (NF-κB) signaling pathway is involved in ammonia-induced mitochondrial dysfunction.

Hyperammonemia is very toxic to the brain, leading to inflammation, disruption of brain cellular energy metabolism and cognitive function. However, the underlying mechanism(s) for these impairments is still not fully understood. This study investigated the effects of ammonia in hippocampal astroglia derived from C57BL/6 mice. Parameters measured included oxygen consumption rates (OCR), ATP, cytochrome c oxidase (COX) activity, alterations in oxidative phosphorylation (OXPHOS), nuclear factor kappa B (NF-κB) subunits, key regulators of mitochondrial biogenesis (peroxisome proliferator-activated receptor gamma coactivator1-alpha (PGC-1α), calcium/calmodulin-dependent protein kinase II (CaMKII), cAMP-response element binding protein (CREB), nuclear factor (erythroid-derived 2)-like 2 (Nrf2), early growth response (Egr) factor family of proteins, and mitochondrial transcription factor A (TFAM). Ammonia was found to decrease mitochondrial numbers, potentially through a CaMKII-CREB-PGC1α-Nrf2 pathway in astroglia. Ammonia did not alter the levels of Egrs and TFAM in astroglia. Ammonia decreased OCR, ATP, COX, and OXPHOS levels in astroglia. To assess whether energy metabolism is reduced by ammonia through NF-κB associated pathways, astroglia were treated with ammonia alone or with NF-κB inhibitors such as Bay11-7082 or SN50. Mitochondrial OCR levels were reduced in the presence of NF-κB inhibitors; however co-treatment of NF-κB inhibitors and ammonia reversed mitochondrial deficits. Further, ammonia increased translocation of the NF-κB p65 into the nucleus of astroglia that correlates with an increased activity of NF-κB. These findings suggest that the NF-κB signaling pathway is putatively involved in ammonia-induced changes in bioenergetics in astroglia. Such research has critical implications for the treatment of disorders in which brain bioenergetics is compromised.

Eco-Pap: The Ecological Modification of the Papanicolaou Stain for Sustainable Cervical Cancer Diagnosis.

OBJECTIVES: To validate the ecological modification of the Papanicolaou stain (Eco-Pap) for the diagnosis of cervical cancer. STUDY DESIGN: A prospective study was performed at the Mother and Child "San Bartolomé" Hospital, Lima, Peru. Reagent handling strategies were divided into three phases: we used (1) Harris progressive hematoxylin (for nuclear staining), (2) a polychromatic solution (a mix of EA-36/Orange G-6 to suppress the use of several alcohol baths), and (3) direct mounting (with Entellan® solution). The cellular details were analyzed by the staining quality index, an external quality control, and the Bethesda System 2014. RESULTS: We evaluated 72,901 cervical smears stained with the Eco-Pap. The validation of the Eco-Pap against the conventional Pap stain was optimal (κ = 0.89; 95% CI: 0.87-0.92), showing a sensibility and specificity of 88.3% (95% CI: 85.1-90.0) and 98.7% (95% CI: 98-99.2), respectively. The Eco-Pap dramatically reduced the environmental pollution caused by 72 L of xylene, hydrochloric acid, and ammonia (6 L each) and mercury oxide. CONCLUSION: The Eco-Pap is an innovative and efficient staining method reducing the use of toxic reagents with carcinogenic potential during cervical cancer screening by exfoliative cytology.

Submucosal hematoma: a new distinctive sign during emergency upper digestive endoscopy for ammonia ingestion.

BACKGROUND: Submucosal hematoma has never been associated with caustic injuries. Long-term follow-up of patients who ingested ammonia is not well known and ammonia ingestion is rare. METHODS: In a Single-center observational study, prospective data were collected from 2009 to 2013, in patients over the age of 14 years old referred for ammonia ingestion. The emergency and follow-up endoscopic data and the outcome were reported. RESULTS: Ammonia ingestion occurred in 43 patients. Submucosal hematoma of the gastric wall was a distinctive endoscopic sign observed in 15 (34.8%) cases. Oropharyngeal lesions were present in 30 (69.8%) patients, which was associated with ingestion with suicidal intent in 18 cases. Mild and severe endoscopic lesions (grade IIB to IIIB) were found in 16 (37.2%) cases with 10 (23.3%) cases presenting submucosal hematoma at initial endoscopy. A complete spontaneous gastric healing was frequently observed in 36 (83.7%) cases. In 11 cases with submucosal hematoma, a favourable outcome was observed with a medical treatment, however 6 of these patients had severe endoscopic lesions initially. CONCLUSIONS: Submucosal hematoma of the gastric wall is an endoscopic sign occurring frequently in ammonia ingestion. Submucosal hematoma should be distinguished from necrosis in order to avoid false misclassification in favour of more severe lesions, which would lead to an abusive surgery.

Ventilatory disorders associated with occupational inhalation exposure to nitrogen trihydride (ammonia).

Respiratory effects of long term exposure to low levels of ammonia have not been thoroughly investigated. In this cross sectional study, 124 male subjects (67 high exposed and 57 low exposed), occupationally exposed to low levels of ammonia and 120 male referent individuals were investigated. Airborne concentrations of ammonia were measured and subjects underwent spirometry tests prior to and at end of their daily work shift. Average concentrations of ammonia in the breathing zones of the high and low exposed employees were found to be 1.35 ± 4.59 and 0.29 ± 0.31 ppm, respectively. Additionally, mean baseline values of some parameters of pulmonary function such as Vital Capacity (VC) and Forced Expiratory Volume in the first second (FEV1) in the high exposed group were significantly lower than those of referent individuals. Similarly, significant reversible cross shift decrements were noted in FEV1, VC and Forced Vital Capacity (FVC) of exposed employees. These findings indicate that exposure to low levels of ammonia is associated with significant chronic irreversible and acute reversible decrements in the lungs' functional capacity.

Rhinitis and sleep disorders: The trigeminocardiac reflex link?

Rhinitis, allergic or non-allergic, is an inflammatory condition of the nose. It is associated with a wide range of sleep disorders that are generally attributed to nasal congestion and presence of inflammatory mediators like cytokines and interleukins. However, the pathophysiological mechanisms behind these sleep disorders remain unclear. On the other hand, the trigeminocardiac reflex (TCR) has recently been linked to various sleep disorders like obstructive sleep apnea, sleep bruxism and rapid eye movement (REM) sleep apnea. TCR can be incited by stimulation of the trigeminal nerve or the area innervated by its branches including the nasal mucosa. Trigeminal nasal afferents can be activated on exposure to noxious stimuli (mechanical or chemical) like ammonia vapors, carbon-dioxide, nicotine, hypertonic saline, air-puffs and smoke. In rhinitis, there is associated neuronal hyper-responsiveness of sensory nasal afferents due to inflammation (which can be suppressed by steroids). This may further lead to increased occurrence of TCR in rhinitis. Moreover, there is involvement of autonomic nervous system both in rhinitis and TCR. In TCR, parasympathetic over activity and sympathetic inhibition leads to sudden onset bradycardia, hypotension, apnea and gastric motility. Also, the autonomic imbalance reportedly plays a significant role in the pathophysiology of rhinitis. Thus, considering these facts we hypothesize that the TCR could be the link between rhinitis and sleep disorders and we believe that further research in this direction may yield significant development in our understanding of sleep disorders in rhinitis.

Effects of alpha-lipoic acid supplementation on growth performance, antioxidant capacity and biochemical parameters for ammonia-exposed broilers.

In order to estimate the effect of alpha-lipoic acid (LA) supplementation on relieving ammonia stress of broilers, 180 22-day-old male broilers were assigned to three groups, six replicates in each group and 10 birds per replicate. The three groups were: (1) a control group without ammonia stress; (2) exposure to 70 ppm atmospheric ammonia (AM); (3) exposure to 70 ppm atmospheric ammonia and administration of 300 mg/kg LA (AM + LA). The experimental period was 3 weeks. Results showed that average daily weight gain was increased and feed conversion ratio was decreased in the AM + LA group, compared with the AM group (P < 0.05). Total superoxide dismutase and glutathione peroxidase activities in serum, and glutathione content in liver were higher in the AM + LA group than that in the AM group (P < 0.05); however, serum malondialdehyde content was decreased by LA addition (P < 0.05). Additionally, serum glutamic-pyruvic transaminase, creatine kinase and lactate dehydrogenase activities were reduced and albumin level was increased by LA addition (P < 0.05). In conclusion, LA addition could relieve ammonia stress to restore broiler production performance to normal levels.

The role of oncoprotein NM23 gene from Exopalaemon carinicauda is response to pathogens challenge and ammonia-N stress.

Oncoprotein NM23, as a family of genes encoding the nucleoside diphosphate (NDP) kinase, plays important roles in bioenergetics, DNA replication, differentiation and tumor metastasis. In this study, a full-length cDNA of NM23 (designated EcNM23) was cloned from Exopalaemon carinicauda by using rapid amplification of cDNA ends (RACE) approaches. The full-length cDNA of EcNM23 was 755 bp, which contains an open reading frame (ORF) of 518 bp, encoding a 175 amino-acid polypeptide with the predicted molecular weight of 19.60 kDa and estimated isoelectric point of 7.67. The deduced amino acid sequence of EcNM23 shared high identity (86%-93%) with that of other crustaceans. a NDP kinase super family signature was identified in E. carinicauda EcNM23. Quantitative real-time RT-qPCR analysis indicated that EcNM23 was expressed in all the examined tissues with the high expression level in hemocytes and ovary. The EcNM23 expression in immune-related tissues changed rapidly and reached peak at different time after pathogens (Vibrio parahaemolyticus and WSSV) challenge and ammonia-N stress treatment. The results suggested that EcNM23 might be associated with the immune defenses to pathogens infection and ammonia-N stress in E. carinicauda.

High environmental ammonia elicits differential oxidative stress and antioxidant responses in five different organs of a model estuarine teleost (Dicentrarchus labrax).

We investigated oxidative status and antioxidant profile in five tissues (brain, liver, gills, muscle and kidney) of European sea bass (Dicentrarchus labrax) when exposed to high environmental ammonia (HEA, 20 mg/L~1.18 mM as NH4HCO3) for 12 h, 2 days, 3.5 days, 7.5 days and 10 days. Results show that HEA triggered ammonia accumulation and induced oxidative stress in all tissues. Unlike other organs, hydrogen peroxide (H2O2) and malondialdehyde (MDA) accumulation in liver were restored to control levels. This recovery was associated with a concomitant augmentation in superoxide dismutase (SOD), catalase (CAT), components of glutathione redox cycle (glutathione peroxidase GPX, glutathione reductase, reduced glutathione), ascorbate peroxidase activity and reduced ascorbate content. On the contrary, in brain during prolonged exposure many of these anti-oxidant enzymes were either unaffected or inhibited, which resulted in persistent over-accumulation of H2O2 and MDA. Branchial and renal tissue both involved in osmo-regulation, revealed an entirely dissimilar compensatory response; the former rely mainly on the ascorbate dependent defensive system while the glutathione catalytic pathway was activated in the latter. In muscle, GPX activity first rose (3.5 days) followed by a subsequent drop, counterbalanced by simultaneous increment of CAT. HEA resulted in a relatively mild oxidative stress in the muscle and kidney, probably explaining the modest anti-oxidative responses. Our findings exemplify that oxidative stress as well as antioxidant potential are qualitatively diverse amongst different tissues, thereby demonstrating that for biomonitoring studies the screening of adaptive responses at organ level should be preferred over whole body response.

Inhalación masiva de amoniaco: reporte de dos casos / Massive ammonia inhalation: report of two cases

Ammonia (NH3) is an irritant and corrosive gas whose inhalation at high concentrations mainly occurs during agricultural and industrial activities, as occupational accidents. The extent and severity of the damage depends on the concentration and time of exposure to the toxic, which can cause skin, eye, respiratory and life-threatening injuries. We present two cases of patients acutely exposed to high concentrations of NH3. Both patients survived to the acute phase of the respiratory injury, but developed chronic lung derangements.

El amoniaco (NH3) es un gas irritante y corrosivo cuya inhalación aguda en altas concentraciones se produce principalmente durante accidentes laborales en el sector agrícola e industrial. La extensión y severidad del daño depende de la concentración y tiempo de exposición al tóxico, el cual puede causar lesiones a nivel cutáneo, ocular, respiratorio y riesgo vital. Presentamos dos casos de pacientes expuestos en forma aguda a NH3 en altas concentraciones. Ambos pacientes sobrevivieron a la fase aguda y evolucionaron con lesiones respiratorias crónicas.

Smokers' and nonsmokers' beliefs about harmful tobacco constituents: implications for FDA communication efforts.

INTRODUCTION: Legislation requires the U.S. Food and Drug Administration (FDA) to release information to the public about harmful constituents in tobacco and tobacco smoke. To inform these efforts, we sought to better understand how smokers and nonsmokers think about tobacco constituents. METHODS: In October 2012, 300 U.S. adults aged 18-66 years completed a cross-sectional Internet survey. The questions focused on 20 harmful tobacco constituents that the FDA has prioritized for communicating with the public. RESULTS: Most participants had heard of 7 tobacco constituents (ammonia, arsenic, benzene, cadmium, carbon monoxide, formaldehyde, and nicotine), but few participants had heard of the others (e.g., acrolein). Few participants correctly understood that many constituents were naturally present in tobacco. Substances that companies add to cigarette tobacco discouraged people from wanting to smoke more than substances that naturally occur in cigarette smoke (p < .001). Ammonia, arsenic, carbon monoxide, and formaldehyde being in cigarettes elicited the most discouragement from smoking. Constituents elicited greater discouragement from wanting to smoke if respondents were nonsmokers (ß = -.34, p < .05), had negative images of smokers (i.e., negative smoker prototypes; ß = .19, p < .05), believed constituents are added to tobacco (ß = .14, p < .05), or were older (ß = .16, p < .05). CONCLUSIONS: Our study found low awareness of most tobacco constituents, with greater concern elicited by additives. Efforts to communicate health risks of tobacco constituents should consider focusing on ones that elicited the most discouragement from smoking.

Properties and expression of Na+/K+-ATPase α-subunit isoforms in the brain of the swamp eel, Monopterus albus, which has unusually high brain ammonia tolerance.

The swamp eel, Monopterus albus, can survive in high concentrations of ammonia (>75 mmol l(-1)) and accumulate ammonia to high concentrations in its brain (4.5 µmol g(-1)). Na(+)/K(+)-ATPase (Nka) is an essential transporter in brain cells, and since NH4(+) can substitute for K(+) to activate Nka, we hypothesized that the brain of M. albus expressed multiple forms of Nka α-subunits, some of which might have high K(+) specificity. Thus, this study aimed to clone and sequence the nka α-subunits from the brain of M. albus, and to determine the effects of ammonia exposure on their mRNA expression and overall protein abundance. The effectiveness of NH4(+) to activate brain Nka from M. albus and Mus musculus was also examined by comparing their Na(+)/K(+)-ATPase and Na(+)/NH4(+)-ATPase activities over a range of K(+)/NH4(+) concentrations. The full length cDNA coding sequences of three nkaα (nkaα1, nkaα3a and nkaα3b) were identified in the brain of M. albus, but nkaα2 expression was undetectable. Exposure to 50 mmol l(-1) NH4Cl for 1 day or 6 days resulted in significant decreases in the mRNA expression of nkaα1, nkaα3a and nkaα3b. The overall Nka protein abundance also decreased significantly after 6 days of ammonia exposure. For M. albus, brain Na(+)/NH4(+)-ATPase activities were significantly lower than the Na(+)/K(+)-ATPase activities assayed at various NH4(+)/K(+) concentrations. Furthermore, the effectiveness of NH4(+) to activate Nka from the brain of M. albus was significantly lower than that from the brain of M. musculus, which is ammonia-sensitive. Hence, the (1) lack of nkaα2 expression, (2) high K(+) specificity of K(+) binding sites of Nkaα1, Nkaα3a and Nkaα3b, and (3) down-regulation of mRNA expression of all three nkaα isoforms and the overall Nka protein abundance in response to ammonia exposure might be some of the contributing factors to the high brain ammonia tolerance in M. albus.

Occupational exposure to cleaning products and asthma in hospital workers.

OBJECTIVE: Cleaning products may cause work-related asthma, but information regarding the specific exposures involved is scarce. We aimed to determine the associations between asthma and occupational exposure to cleaning agents in hospital workers. METHODS: Analyses were conducted in 179 (136 women) hospital workers and a reference population of 545 subjects (18-79 years) from the French case-control and familial Epidemiological study on the Genetics and Environment of Asthma (2003-2007). Exposures to cleaning agents were estimated using three methods: self-report, expert assessment and an asthma-specific job-exposure matrix (JEM). Associations between cleaning products and current asthma were evaluated by logistic regressions, stratified by sex and adjusted for age and smoking status. RESULTS: According to expert assessment, 55% of male and 81% of female hospital workers were exposed to cleaning/disinfecting tasks weekly (p<0.001). No association was observed between cleaning/disinfecting tasks and current asthma in men or in women whatever the assessment method used. In women, exposure to decalcifiers (expert assessment) was associated with current asthma (OR (95% CI):2.38 (1.06 to 5.33)). In hospital workers classified as exposed according to both the expert assessment and the JEM, additional associations were observed for exposure to ammonia (3.05 (1.19 to 7.82)) and to sprays with moderate/high intensity (2.87 (1.02 to 8.11)). CONCLUSIONS: Female hospital workers are often exposed to numerous cleaning products, some of which were markedly associated with current asthma. Low numbers prevented a meaningful analysis in men. Objective and more accurate estimates of occupational exposure to cleaning products are needed to better understand the adverse effects of cleaning products.

The correlation between thermal and noxious gas environments, pig productivity and behavioral responses of growing pigs.

Correlations between environmental parameters (thermal range and noxious gas levels) and the status (productivity, physiological, and behavioral) of growing pigs were examined for the benefit of pig welfare and precision farming. The livestock experiment was conducted at a Seoul National University station in South Korea. Many variations were applied and the physiological and behavioral responses of the growing pigs were closely observed. Thermal and gas environment parameters were different during the summer and winter seasons, and the environments in the treatments were controlled in different manners. In the end, this study finds that factors such as Average Daily Gain (ADG), Adrenocorticotropic Hormone (ACTH), stress, posture, and eating habits were all affected by the controlled environmental parameters and that appropriate control of the foregoing could contribute to the improvement of precision farming and pig welfare.

Effects of high environmental ammonia on branchial ammonia excretion rates and tissue Rh-protein mRNA expression levels in seawater acclimated Dungeness crab Metacarcinus magister.

In the present study of the marine Dungeness crabs Metacarcinus magister, the long term effects of high environmental ammonia (HEA) on hemolymph ammonia and urea concentrations, branchial ammonia excretion rates and mRNA expression levels of the crustacean Rh-like ammonia transporter (RhMM), H(+)-ATPase (subunit B), Na(+)/K(+)-ATPase (α-subunit) and Na(+)/H(+)-exchanger (NHE) were investigated. Under control conditions, the crabs' hemolymph exhibited a total ammonia concentration of 179.3±14.5µmol L(-1), while urea accounted for 467.2±33.5µmol L(-1), respectively. Both anterior and posterior gills were capable of excreting ammonia against a 16-fold inwardly directed gradient. Under control conditions, mRNA expression levels of RhMM were high in the gills in contrast to very low expression levels in all other tissues investigated, including the antennal gland, hepatopancreas, and skeletal muscle. After exposure to 1mmol L(-1) NH(4)Cl, hemolymph ammonia increased within the first 12h to ca. 500µmol L(-1) and crabs were able the keep this hemolymph ammonia level for at least 4 days. During this initial period, branchial RhMM and H(+)-ATPase (subunit B) mRNA expression levels roughly doubled. After 14 days of HEA exposure, hemolymph ammonia raised up to environmental levels, whereas urea levels increased by ca. 30%. At the same time, whole animal ammonia and urea excretion vanished. Additionally, branchial RhMM, H(+)-ATPase, Na(+)/K(+)-ATPase and NHE mRNA levels decreased significantly after long term HEA exposure, whereas expression levels of RhMM in the internal tissues increased substantially. Interestingly, crabs acclimated to HEA showed no mortality even after 4 weeks of HEA exposure. This suggests that M. magister possesses a highly adaptive mechanism to cope with elevated ammonia concentrations in its body fluids, including an up-regulation of an Rh-like ammonia transporter in the internal tissues and excretion or storage of waste nitrogen in a so far unknown form.