Hydrochloric Acid: A strong corrosive acid that is commonly used as a laboratory reagent. It is formed by dissolving hydrogen chloride in water. GASTRIC ACID is the hydrochloric acid component of GASTRIC JUICE.Pneumonia, Aspiration: A type of lung inflammation resulting from the aspiration of food, liquid, or gastric contents into the upper RESPIRATORY TRACT.Nitric Acid: Nitric acid (HNO3). A colorless liquid that is used in the manufacture of inorganic and organic nitrates and nitro compounds for fertilizers, dye intermediates, explosives, and many different organic chemicals. Continued exposure to vapor may cause chronic bronchitis; chemical pneumonitis may occur. (From Merck Index, 11th ed)Gastric Juice: The liquid secretion of the stomach mucosa consisting of hydrochloric acid (GASTRIC ACID); PEPSINOGENS; INTRINSIC FACTOR; GASTRIN; MUCUS; and the bicarbonate ion (BICARBONATES). (From Best & Taylor's Physiological Basis of Medical Practice, 12th ed, p651)Decalcification Technique: Removal of minerals from bones during bone examination.Trifluoroacetic Acid: A very strong halogenated derivative of acetic acid. It is used in acid catalyzed reactions, especially those where an ester is cleaved in peptide synthesis.Countercurrent Distribution: A method of separation of two or more substances by repeated distribution between two immiscible liquid phases that move past each other in opposite directions. It is a form of liquid-liquid chromatography. (Stedman, 25th ed)Esophagus: The muscular membranous segment between the PHARYNX and the STOMACH in the UPPER GASTROINTESTINAL TRACT.Hydrogen-Ion Concentration: The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH = log 1/2[1/(H+)], where (H+) is the hydrogen ion concentration in gram equivalents per liter of solution. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Stomach: An organ of digestion situated in the left upper quadrant of the abdomen between the termination of the ESOPHAGUS and the beginning of the DUODENUM.Acids: Chemical compounds which yield hydrogen ions or protons when dissolved in water, whose hydrogen can be replaced by metals or basic radicals, or which react with bases to form salts and water (neutralization). An extension of the term includes substances dissolved in media other than water. (Grant & Hackh's Chemical Dictionary, 5th ed)Fluoroacetates: Derivatives of acetic acid with one or more fluorines attached. They are almost odorless, difficult to detect chemically, and very stable. The acid itself, as well as the derivatives that are broken down in the body to the acid, are highly toxic substances, behaving as convulsant poisons with a delayed action. (From Miall's Dictionary of Chemistry, 5th ed)Achlorhydria: A lack of HYDROCHLORIC ACID in GASTRIC JUICE despite stimulation of gastric secretion.Parietal Cells, Gastric: Rounded or pyramidal cells of the GASTRIC GLANDS. They secrete HYDROCHLORIC ACID and produce gastric intrinsic factor, a glycoprotein that binds VITAMIN B12.Gastric Acid: Hydrochloric acid present in GASTRIC JUICE.Sulfuric Acids: Inorganic and organic derivatives of sulfuric acid (H2SO4). The salts and esters of sulfuric acid are known as SULFATES and SULFURIC ACID ESTERS respectively.Gastric Fistula: Abnormal passage communicating with the STOMACH.Gastric Mucosa: Lining of the STOMACH, consisting of an inner EPITHELIUM, a middle LAMINA PROPRIA, and an outer MUSCULARIS MUCOSAE. The surface cells produce MUCUS that protects the stomach from attack by digestive acid and enzymes. When the epithelium invaginates into the LAMINA PROPRIA at various region of the stomach (CARDIA; GASTRIC FUNDUS; and PYLORUS), different tubular gastric glands are formed. These glands consist of cells that secrete mucus, enzymes, HYDROCHLORIC ACID, or hormones.Sodium Hydroxide: A highly caustic substance that is used to neutralize acids and make sodium salts. (From Merck Index, 11th ed)Alkalosis: A pathological condition that removes acid or adds base to the body fluids.Pentagastrin: A synthetic pentapeptide that has effects like gastrin when given parenterally. It stimulates the secretion of gastric acid, pepsin, and intrinsic factor, and has been used as a diagnostic aid.Pepsin A: Formed from pig pepsinogen by cleavage of one peptide bond. The enzyme is a single polypeptide chain and is inhibited by methyl 2-diaazoacetamidohexanoate. It cleaves peptides preferentially at the carbonyl linkages of phenylalanine or leucine and acts as the principal digestive enzyme of gastric juice.Appendix: A worm-like blind tube extension from the CECUM.Acidosis: A pathologic condition of acid accumulation or depletion of base in the body. The two main types are RESPIRATORY ACIDOSIS and metabolic acidosis, due to metabolic acid build up.Duodenum: The shortest and widest portion of the SMALL INTESTINE adjacent to the PYLORUS of the STOMACH. It is named for having the length equal to about the width of 12 fingers.Sodium Chloride: A ubiquitous sodium salt that is commonly used to season food.Spectrophotometry, Atomic: Spectrophotometric techniques by which the absorption or emmision spectra of radiation from atoms are produced and analyzed.Secretin: A peptide hormone of about 27 amino acids from the duodenal mucosa that activates pancreatic secretion and lowers the blood sugar level. (USAN and the USP Dictionary of Drug Names, 1994, p597)Stomach Ulcer: Ulceration of the GASTRIC MUCOSA due to contact with GASTRIC JUICE. It is often associated with HELICOBACTER PYLORI infection or consumption of nonsteroidal anti-inflammatory drugs (NSAIDS).Bicarbonates: Inorganic salts that contain the -HCO3 radical. They are an important factor in determining the pH of the blood and the concentration of bicarbonate ions is regulated by the kidney. Levels in the blood are an index of the alkali reserve or buffering capacity.Foreign Bodies: Inanimate objects that become enclosed in the body.Epidermis: The external, nonvascular layer of the skin. It is made up, from within outward, of five layers of EPITHELIUM: (1) basal layer (stratum basale epidermidis); (2) spinous layer (stratum spinosum epidermidis); (3) granular layer (stratum granulosum epidermidis); (4) clear layer (stratum lucidum epidermidis); and (5) horny layer (stratum corneum epidermidis).Caustics: Strong alkaline chemicals that destroy soft body tissues resulting in a deep, penetrating type of burn, in contrast to corrosives, that result in a more superficial type of damage via chemical means or inflammation. Caustics are usually hydroxides of light metals. SODIUM HYDROXIDE and potassium hydroxide are the most widely used caustic agents in industry. Medically, they have been used externally to remove diseased or dead tissues and destroy warts and small tumors. The accidental ingestion of products (household and industrial) containing caustic ingredients results in thousands of injuries per year.Alkalies: Usually a hydroxide of lithium, sodium, potassium, rubidium or cesium, but also the carbonates of these metals, ammonia, and the amines. (Grant & Hackh's Chemical Dictionary, 5th ed)Burns, ChemicalCalcium Hydroxide: A white powder prepared from lime that has many medical and industrial uses. It is in many dental formulations, especially for root canal filling.Magnesium Sulfate: A small colorless crystal used as an anticonvulsant, a cathartic, and an electrolyte replenisher in the treatment of pre-eclampsia and eclampsia. It causes direct inhibition of action potentials in myometrial muscle cells. Excitation and contraction are uncoupled, which decreases the frequency and force of contractions. (From AMA Drug Evaluations Annual, 1992, p1083)Magnesium Chloride: Magnesium chloride. An inorganic compound consisting of one magnesium and two chloride ions. The compound is used in medicine as a source of magnesium ions, which are essential for many cellular activities. It has also been used as a cathartic and in alloys.Health Fairs: Community health education events focused on prevention of disease and promotion of health through audiovisual exhibits.Magnesium: A metallic element that has the atomic symbol Mg, atomic number 12, and atomic weight 24.31. It is important for the activity of many enzymes, especially those involved in OXIDATIVE PHOSPHORYLATION.Magnesium Deficiency: A nutritional condition produced by a deficiency of magnesium in the diet, characterized by anorexia, nausea, vomiting, lethargy, and weakness. Symptoms are paresthesias, muscle cramps, irritability, decreased attention span, and mental confusion, possibly requiring months to appear. Deficiency of body magnesium can exist even when serum values are normal. In addition, magnesium deficiency may be organ-selective, since certain tissues become deficient before others. (Harrison's Principles of Internal Medicine, 12th ed, p1936)Daphnia: A diverse genus of minute freshwater CRUSTACEA, of the suborder CLADOCERA. They are a major food source for both young and adult freshwater fish.Immobilization: The restriction of the MOVEMENT of whole or part of the body by physical means (RESTRAINT, PHYSICAL) or chemically by ANALGESIA, or the use of TRANQUILIZING AGENTS or NEUROMUSCULAR NONDEPOLARIZING AGENTS. It includes experimental protocols used to evaluate the physiologic effects of immobility.Toxicity Tests, Acute: Experiments designed to determine the potential toxic effects of one-time, short-term exposure to a chemical or chemicals.Pasteuria: A genus of GRAM-POSITIVE ENDOSPORE-FORMING BACTERIA in the family Pasteuriaceae. It is transmitted via soil or waterborne SPORES.Formularies as Topic: Works about lists of drugs or collections of recipes, formulas, and prescriptions for the compounding of medicinal preparations. Formularies differ from PHARMACOPOEIAS in that they are less complete, lacking full descriptions of the drugs, their formulations, analytic composition, chemical properties, etc. In hospitals, formularies list all drugs commonly stocked in the hospital pharmacy.Restraint, Physical: Use of a device for the purpose of controlling movement of all or part of the body. Splinting and casting are FRACTURE FIXATION.LiechtensteinEuropean Union: The collective designation of three organizations with common membership: the European Economic Community (Common Market), the European Coal and Steel Community, and the European Atomic Energy Community (Euratom). It was known as the European Community until 1994. It is primarily an economic union with the principal objectives of free movement of goods, capital, and labor. Professional services, social, medical and paramedical, are subsumed under labor. The constituent countries are Austria, Belgium, Denmark, Finland, France, Germany, Greece, Ireland, Italy, Luxembourg, Netherlands, Portugal, Spain, Sweden, and the United Kingdom. (The World Almanac and Book of Facts 1997, p842)IcelandIndustry: Any enterprise centered on the processing, assembly, production, or marketing of a line of products, services, commodities, or merchandise, in a particular field often named after its principal product. Examples include the automobile, fishing, music, publishing, insurance, and textile industries.EuropeConsumer Satisfaction: Customer satisfaction or dissatisfaction with a benefit or service received.

A acid-stable analogue of the 3-beta-D-ribofuranoside of Y-base. (1/745)

A cyclonucleoside analogue of Y(TU) riboside has been prepared and shown to be relatively stable in M-hydrochloric acid solution at room temperature.  (+info)

Experimental acid-aspiration pneumonia in the rabbit. A pathologic and morphometric study. (2/745)

Four anesthetized rabbits given intratracheal injections of hydrochloric acid, pH 1.5, 2 ml/kg, were killed 4 h later. A fifth rabbit was an untreated control. Each lung had a few red-brown patches of compression atelectasis. Microscopically, treated lungs had a severe exudative necrotizing bronchitis, bronchiolitis, and alveolitis. There was also intra-alveolar hemorrhage and edema. Electron microscopy showed folds, projections and focal swellings of type I cells lining affected alveoli. A morphometric study showed 69% of parenchyma to be normal, 26% edematous and 5% hemorrhagic. In the airways 58% of the epithelium was damaged.  (+info)

The magnitude of changes in guanidine-HCl unfolding m-values in the protein, iso-1-cytochrome c, depends upon the substructure containing the mutation. (3/745)

Hydrophilic to hydrophobic mutations have been made at 11 solvent exposed sites on the surface of iso-1-cytochrome c. Most of these mutations involve the replacement of lysine with methionine, which is nearly isosteric with lysine. Minimal perturbation to the native structure is expected, and this expectation is confirmed by infrared amide I spectroscopy. Guanidine hydrochloride denaturation studies demonstrate that these variants affect the magnitude of the m-value, the rate of change of free energy with respect to denaturant concentration, to different degrees. Changes in m-values are indicative of changes in the equilibrium folding mechanism of a protein. Decreases in m-values are normally thought to result either from an increased population of intermediates during unfolding or from a more compact denatured state. When cytochrome c is considered in terms of its thermodynamic substructures, the changes in the m-value for a given variant appear to depend upon the substructure in which the mutation is made. These data indicate that the relative stabilities and physical properties of substructures of cytochrome c play an important determining role in the equilibrium folding mechanism of this protein.  (+info)

Preferential acid-catalyzed hydrolysis of the formamide linkage of N'-formylkynurenine in frozen solution. (4/745)

Acid-catalyzed hydrolysis of the formamide linkage of N-acetyl-N'-formyl-L-kynurenineamide in frozen dilute hydrochloric acid solution followed first-order kinetics, yielding N-acetyl-L-kynurenineamide as the sole reaction product. The maximum rate of reaction in the frozen solution was found at around -7.5 degrees and approximated that of the reaction in liquid solution at 40 degrees. By freezing the dilute acid solution at -8 degrees the reaction was accelerated by 60 times compared with that in super-cooled liquid solution at the same temperature.  (+info)

Interference in the quantitation of methylated arsenic species in human urine. (5/745)

The aim of this paper is to report on the presence of chemical interferences in the quantitation of methylated arsenic species in human urine when using a method based on selective volatile arsine species generation, chromatographic separation, and hydride generation atomic absorption spectrometry (HGAAS) detection. An abnormal profile of methylated arsenic species characterized by the absence of the peak corresponding to dimethylarsinic acid (DMA) was observed in urine from some individuals exposed to arsenic via drinking water and living in rural communities of northwestern Argentina. The absence of this peak persisted even after the addition of known amounts of DMA to the samples. However, the DMA peak appeared after urine digestion with hydrochloric acid (2M). Samples showing interferences were provided by individuals who had mate consumption and coca-leaf chewing habits. Because the relative proportions of methylated arsenic species present in urine have been used to evaluate the efficiency of the methylation process, interferences in the formation or detection of methylarsines may cause underestimation of As exposure and also lead to erroneous conclusions about relative biomethylation efficiencies. Therefore, we recommend that urine samples should be digested with 2M HCl before performing speciation analysis using HGAA techniques. Further studies on the impact of this type of interferences on other arsenic speciation methods are also required.  (+info)

Larynx vs. esophagus as reflexogenic sites for acid-induced bronchoconstriction in dogs. (6/745)

Bronchoconstriction in asthmatic patients is frequently associated with gastroesophageal reflux. However, it is still unclear whether bronchoconstriction originates from the esophagus or from aspiration of the refluxate into the larynx and larger airway. We compared the effect of repeated esophageal and laryngeal instillations of HCl-pepsin (pH 1.0) on tracheal smooth muscle activity in eight anesthetized and artificially ventilated dogs. Saline was used as control. We used pressure in the cuff of an endotracheal tube (Pcuff) as a direct index of smooth muscle activity at the level of the larger airways controlled by vagal efferents. The Pcuff values of the first 60 s after instillations were averaged, and the difference from the baseline values was evaluated. Changes in Pcuff were significantly greater with laryngeal than with esophageal instillations (P = 0.0166). HCl-pepsin instillation into the larynx evoked greater responses than did saline (P = 0.00543), whereas no differences were detected with esophageal instillations. Repeated laryngeal exposure enhanced the responsiveness significantly (P < 0. 001). Our data indicate that the larynx is more important than the esophagus as a reflexogenic site for the elicitation of reflex bronchoconstriction in response to acidic solutions.  (+info)

Vagal esophageal receptors in anesthetized dogs: mechanical and chemical responsiveness. (7/745)

This study was performed to evaluate the characteristics of esophageal receptors in anesthetized and artificially ventilated dogs. The electrical activity of the esophageal afferents was recorded from the peripheral cut end of the cervical vagus nerve. A cuffed catheter was inserted into the esophagus at the level of the third tracheal ring and was used to establish the esophageal location of the endings. Most of the receptors were localized in the intrathoracic portion of the esophagus. The majority of the receptors studied (36 of 43) showed a slow adaptation to a maintained stretch of the esophageal wall. Vagal cooling blocked receptor activity at temperatures ranging from 3.5 to 25 degrees C. Twenty-eight of 43 receptors, including 4 rapidly adapting endings (RAR), were challenged with saline, HCl + pepsin (HCl-P; pH 1) and distilled water (8 ml, 37 degrees C). HCl-P solutions specifically stimulated only three receptors; saline or water did not. Five slowly adapting receptors and two RARs were also challenged with topically applied capsaicin; only one RAR was stimulated. To ascertain a possible effect of smooth muscle contraction, 17 receptors were tested with intravenous injections of ACh and/or asphyxia; only 4 were stimulated. These characteristics do not support an important reflexogenic role of the esophagus in response to chemical stimuli.  (+info)

Extracellular acidification induces human neutrophil activation. (8/745)

In the current work, we evaluated the effect of extracellular acidification on neutrophil physiology. Neutrophils suspended in bicarbonate-buffered RPMI 1640 medium adjusted to acidic pH values (pH 6.5-7.0) underwent: 1) a rapid transient increase in intracellular free calcium concentration levels; 2) an increase in the forward light scattering properties; and 3) the up-regulation of surface expression of CD18. By contrast, extracellular acidosis was unable to induce neither the production of H2O2 nor the release of myeloperoxidase. Acidic extracellular pH also modulated the functional profile of neutrophils in response to conventional agonists such as FMLP, precipiting immune complexes, and opsonized zymosan. It was found that not only calcium mobilization, shape change response, and up-regulation of CD18 expression but also production of H2O2 and release of myeloperoxidase were markedly enhanced in neutrophils stimulated in acidic pH medium. Moreover, extracellular acidosis significantly delayed neutrophil apoptosis and concomitantly extended neutrophil functional lifespan. Extracellular acidification induced an immediate and abrupt fall in the intracellular pH, which persisted over the 240-s analyzed. A similar abrupt drop in the intracellular pH was detected in cells suspended in bicarbonate-supplemented PBS but not in those suspended in bicarbonate-free PBS. A role for intracellular acidification in neutrophil activation is suggested by the fact that only neutrophils suspended in bicarbonate-buffered media (i.e., RPMI 1640 and bicarbonate-supplemented PBS) underwent significant shape changes in response to extracellular acidification. Together, our results support the notion that extracellular acidosis may intensify acute inflammatory responses by inducing neutrophil activation as well as by delaying spontaneous apoptosis and extending neutrophil functional lifespan.  (+info)

  • In the United States, hydrochloric acid is produced via four main processes: the synthesis of chlorine and hydrogen, the chlorination of organic substances. (reference.com)
  • WaterWorld Magazine recently published a wastewater trial at Lexington Water Systems in Tennessee where Enviro Tech's Peragreen 22WW (22% peracetic acid) product was used as an alternative to chlorine disinfection. (envirotech.com)
  • The results of the trial demonstrated that peracetic acid is an effective alternative to chlorine disinfection without the concern of forming potentially hazardous disinfection byproducts. (envirotech.com)
  • If you're near the ocean entry, where the lava is currently going into the ocean, it creates a material called laze, which is a mixture of hydrochloric acid gas. (terrylonghsore.com)
  • The aim of the investigation is to see how different concentrations of Hydrochloric acid affect the rate at which hydrogen gas is produced when it is reacted with a strip of magnesium. (writework.com)
  • On the other hand, the solutions prepared with citric acid and lactic acid showed no bactericidal activity against any bacterial strains tested in this study despite the low pH. (ingentaconnect.com)
  • Parietal cells release hydrochloric acid into the stomach lumen, thus activating the enzyme. (fgcusg.org)
  • Hydrochloric acid in the stomach lowers the pH to the ideal environment for enzymes to digest proteins into units that the body can use. (reference.com)
  • But you need Hydrochloric Acid to do it's job first and then enzymes do the follow up work. (iherb.com)
  • Our bodies are suppose to make it's own Hydrochloric acid and I've learn that the symptoms of making to much or not enough can be very much the same. (iherb.com)
  • Low Stomach Acid: A Surprising Cause of Indigestion Symptoms. (nyumdi.org)
  • With knowledge of the binders' chemical composition and the acid volume, the binder content can then be calculated. (lu.se)
  • Enviro Tech Chemical Services recently received the first Food Contact Notification (FCN 1654) for the use of our peracetic acid formulation in marinades applied to or injected into processed or unprocessed, cooked or uncooked whole or cut poultry as well as processed and pre-formed meat and poultry products. (envirotech.com)
  • Hydrochloric acid is made in the stomach and is a very helpful chemical. (nyumdi.org)
  • In an application of the zinc and hydrochloric acid experiment, scientists have suggested adding weak hydrochloric acid to irrigation water. (reference.com)
  • Ape kejadahnya minum warm water cuci virus tu pergi stomach and then stomach acid kills the virus. (astdcharlotte.org)
  • Sep 17, 2012 · Here Are 3 Ways to Address Your Stomach Acid Levels Right Now… Good: While eating protein heavy meals, sip on a glass of water that has the juice of half a lemon and 3 tbsp. (nyumdi.org)
  • May 16, 2016 · Below are suggestions for regulating excess acid: Mix 1-2 teaspoons of baking soda in a cup of warm water and drink each day. (nyumdi.org)
  • What about the story that if they get down your throat to the stomach it can be killed by the acid in the stomach and that's why people are advised to take enough water? (nyumdi.org)
  • A high yield of up to 93.7%, crystallinity of 88.6%, and a maximum degradation temperature ( T max ) of 363.9 °C can be achieved by combining hydrochloric acid hydrolysis under hydrothermal conditions and neutralization with ammonia , compared with only 30.2%, 84.3% and 253.2 °C for sulfuric acid hydrolysis , respectively. (rsc.org)