Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0016382 (flushing)
 6,387 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We examined factors that may limit degradation of bacterial protein of Escherichia coli S15 killed by polymorphonuclear leukocytes (PMN). Both human and rabbit PMN degraded up to 40% of [14C]amino acid-labeled protein of ingested and killed E. coli in 2 h as determined by loss of acid-precipitable radioactivity. In contrast, equally bactericidal broken-PMN preparations or isolated granules degraded only about 10% of bacterial protein regardless of pH. To determine whether activation of the respiratory burst contributes to digestion, we compared degradation by intact PMN in room air and under N2. Depletion of O2 by N2 flushing had no effect on the bactericidal activity of either human or rabbit PMN but reduced degradation by approximately 50%. Protein degradation during phagocytosis was also reduced in the presence of cyanide or azide, inhibitors of myeloperoxidase (MPO). PMN of two patients with chronic granulomatous disease ingested and killed E. coli S15 as well as did normal PMN but degraded bacterial protein as did normal PMN incubated under N2. The low degradative activity of PMN disrupted by sonication could be raised to nearly the level of intact PMN incubated in room air by preincubation of the PMN with 10(-7) M formyl-methionyl-leucyl-phenylalanine (fMLP) before sonication and by pretreatment of E. coli with MPO. Depletion of O2 or chloride during these preincubations with formyl-methionyl-leucyl-phenylalanine respectively, virtually abolished and markedly diminished stimulation of bacterial protein degradation. We conclude that enhanced MPO-mediated O2 metabolism of intact PMN plays a role in the digestion of killed E. coli.
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PMID:Respiratory burst facilitates the digestion of Escherichia coli killed by polymorphonuclear leukocytes. 330 66

Acute nitrogen normobaric hypoxic challenges, resulting in an approximately 50% overall survival, were performed in young adult male and female heterozygous OF1 mice under various environmental conditions. The time required to obtain 50% survival was 20 min for a constant pO2 of 42 Torr, and 151 min when pO2 was progressively lowered by nitrogen flushing from 159 to 16.5 Torr. In LD12:12 synchronized animals, survival was significantly (P less than 0.001) less when hypoxia was performed during the light (L) than during the dark (D) phase. Lowering the ambient temperature from 33.8 to 13.2 degrees C increased the length of the progressive hypoxia necessary to obtain a 50% survival of the mice by 1.7 times, and diminished the final pO2 from 35 to 12 Torr. Grouping and crowding both decreased hypoxic survival. A previous stress (starvation) diminished hypoxic resistance of mice, while a preceding hypoxia, carbon monoxide inhalation, or sodium cyanide injection had the opposite effect. In all instances, OF1 females were more resistant than males. Most of these variations can be related to differences in respiratory exchanges, locomotor activity and aggressiveness, which are dependent upon the various experimental environmental parameters.
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PMID:Environmental parameters in the experimental evaluation of a respiratory aggression. 667 64

The present work examines the mechanism of testicular toxicity of acrylonitrile. In testicular centrifugal fractions from Sprague Dawley rats, the metabolism of VCN to cyanide (CN-) was highest in the microsomal fraction and required NADPH for maximum activity. This biotransformation of VCN to CN- was characterized with respect to time (30 min), microsomal protein concentration (1.5 mg ml(-1)), pH (7.5) and temperature (37 degrees C). The V(max) of the reaction was 65.1 pmol CN- mg protein(-1) min(-1) and K(m) was 88.6 micromol VCN. Flushing the microsomes with carbon monoxide (CO)(4:1, CO/O2 v/v), addition of benzimidazole (1 mM) or addition of SKF 525-A (5x10(-4) M) to incubation mixtures significantly inhibited VCN metabolism by 49%, 54% and 37.4% respectively. Activation of VCN to CN- was markedly increased in microsomes obtained from phenobarbital (PB)-treated rats (128.2%). Addition of glutathione (GSH), L-cysteine, D-penicillamine or 2-mercaptoethanol significantly enhanced the release of CN- from VCN 126%, 247%, 202% and 129% of the control value respectively. These findings indicate that VCN is metabolized in the testis via cytochrome P-450 dependent mixed function oxidase system.
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PMID:In-vitro testicular bioactivation of acrylonitrile. 917 82

CO and H(2) have been implicated in methanogenesis from acetate, but it is unclear whether they are directly involved in methanogenesis or electron transfer in acetotrophic methanogens. We compared metabolism of H(2), CO, and formate by cultures of the thermophilic acetotrophic methanogens Methanosarcina thermophila TM-1 and Methanothrix sp. strain CALS-1. M. thermophila accumulated H(2) to partial pressures of 40 to 70 Pa (1 Pa = 0.987 x 10 atm), as has been previously reported for this and other Methanosarcina cultures. In contrast, Methanothrix sp. strain CALS-1 accumulated H(2) to maximum partial pressures near 1 Pa. Growing cultures of Methanothrix sp. strain CALS-1 initially accumulated CO, which reached partial pressures near 0.6 Pa (some CO came from the rubber stopper) during the middle of methanogenesis; this was followed by a decrease in CO partial pressures to less than 0.01 Pa by the end of methanogenesis. Accumulation or consumption of CO by cultures of M. thermophila growing on acetate was not detected. Late-exponential-phase cultures of Methanothrix sp. strain CALS-1, in which the CO partial pressure was decreased by flushing with N(2)-CO(2), accumulated CO to 0.16 Pa, whereas cultures to which ca. 0.5 Pa of CO was added consumed CO until it reached this partial pressure. Cyanide (1 mM) blocked CO consumption but not production. High partial pressures of H(2) (40 kPa) inhibited methanogenesis from acetate by M. thermophila but not by Methanothrix sp. strain CALS-1, and 2 kPa of CO was not inhibitory to M. thermophila but was inhibitory to Methanothrix sp. strain CALS-1. Levels of CO dehydrogenase, hydrogenase, and formate dehydrogenase in Methanothrix sp. strain CALS-1 were 9.1, 0.045, and 5.8 mumol of viologen reduced min mg of protein. These results suggest that CO plays a role in Methanothrix sp. strain CALS-1 similar to that of H(2) in M. thermophila and are consistent with the conclusion that CO is an intermediate in a catabolic or anabolic pathway in Methanothrix sp. strain CALS-1; however, they could also be explained by passive equilibration of CO with a metabolic intermediate.
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PMID:Carbon Monoxide, Hydrogen, and Formate Metabolism during Methanogenesis from Acetate by Thermophilic Cultures of Methanosarcina and Methanothrix Strains. 1634 88

In order to research the impact of continuous extreme rainfall on the water quality of the Dongjiang River, which is a drinking water source, the characteristics of extreme rainfall events in the basin were analyzed for last 38 years. The impacts of these events on water quality are discussed by considering both hydrological data and water quality data. Using SWAT2012 software, a high-precision basin model was established for the flux of major pollutants during extreme rainfall and water quality. The results indicate that there were 173 extreme rainfall events in the Dongjiang River basin over the past 38 years. The annual frequency of extreme rainfall events in high-flow years was higher than in other years. During the year, rainfall was mainly affected by climate, particularly from March to September (80%), with the peak rainfall usually occurring in June. Spatially, the Zengcheng-Bolo-Huizhou-Longmen area had the highest frequency of extreme events. During the study period, rainfall was significantly positively correlated with the concentrations of cyanide, Pb, Fe, Mn, TP, and with turbidity, and the correlation coefficients for the concentrations of TP and turbidity with rainfall were relatively high. Rainfall was significantly negatively correlated with pH, conductivity, the concentration of Zn, as well as some other indicators. These observations show that water quality is affected by rainfall to some extent. Turbidity, TN, ammonia nitrogen, and TP concentrations all showed increasing trends, to different degrees, during rainstorm runoff periods. Turbidity and TP concentrations showed a significant and consistent relationship with flow rate, peaking earlier than the flow rate peak (by approximately 1 d), showing a significant initial flushing effect. The pH curve showed an opposite trend to the flow rate, forming a "V" shape, which may be affected by the rainfall, soil acidity, and confluence conditions in the upstream mountains. Ammonia nitrogen was subject to initial flushing in the early stages of extreme rainfall but was diluted by the clean rainwater; initially, ammonia nitrogen showed high values that declined during the middle and late stages. The variations in pollutant loads were consistent with that of runoff flux, and the peaks in TN, ammonia nitrogen, and TP flux appeared later than the flow peak (by approximately 1 d), thus differing from the pollutant concentration peak. The pollutant load mainly showed a significant increase during storm runoff periods. The proportion of pollutant COD, ammonia nitrogen, and TP transported by 59.48% of the runoff reached 68.42%, 54.68%, and 70.20%, respectively, demonstrating the characteristics of rapid and high-impact pollutant loads. These characteristics have a great influence on the quality of Dongjiang River drinking water and it is suggested that initial rainwater treatment should be strengthened to reduce the negative impact of rainstorm runoff periods on water quality.
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PMID:[Effects of Continuous Extreme Rainfall on Water Quality of the Dongjiang River Basin]. 3185 11

Cyanide is notoriously known to the public for more than a century now as a weapon of mass destruction (Zyklon B gas - hydrogen cyanide used by Nazis), an agent for chemical warfare during World War I (hydrogen cyanide) and very infamous "Suicide Pill" used in the past by military and espionage organizations during World War II (potassium cyanide). During the modern industrial era, cyanide poisoning is commonly associated with the industrial exposure and domestic fires. But there is little awareness about potentially fatal consequences of cyanide poisoning from common food sources. Here, we present the case report of a 79-year-old female with acute cyanide poisoning from improperly prepared cassava leaves. Symptoms from ingested toxin may start a few hours after exposure, which include headache, confusion, ataxia, seizures, palpitations, nausea, vomiting, abdominal pain, flushing, and itching of the skin. Patients may develop hypotension, cardiac arrhythmias, renal failure, hepatic necrosis, rhabdomyolysis, and metabolic acidosis; a multisystem manifestation of hypoxia at the cellular level. Multiple treatment strategies are available to treat cyanide poisoning, including sodium nitrite, sodium thiosulfate, and hydroxycobalamine. This is one of the scenarios where a thorough history, awareness of agents causing cyanide toxicity and knowledge of clinical manifestations can help avoid delays in prompt decision-making for appropriate treatment, thus reducing morbidity, mortality, and prolonged hospital course.
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PMID:Case Report of Lethal Toxin Lurking in an Edible Plant. 3190 2

It is well-known that aldehydes resulting from the in vivo oxidation of primary alcohols are toxic. Here, we experimentally demonstrate in rat models that the dipeptide cysteinylglycine (CG), formed in vivo from its oxidized product, cystinyl-bis-glycine (CbG), will sequester acetaldehyde and isoamyl aldehyde, two model aldehydes resulting from the oxidation of ethanol and isoamyl alcohol, respectively, and excrete them in urine as their respective conjugation products with CG. These data suggest that a whole series of toxic aldehydes can be sequestered and detoxified by CG and may prevent the flushing syndrome exhibited by individuals with a defective enzyme that converts acetaldehyde to acetate. The data also suggest the possibility of alleviating the hangover syndrome we believe to be caused by aldehydes, such as isoamyl aldehyde derived from short, branched-chain alcohols, present as congeners in certain alcoholic beverages. The sequestration of other toxic agents, such as cyanide, that can react with CG can also be envisioned.
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PMID:Sequestration and Elimination of Toxic Aldehydes. 3198 17