The effects of nicotinic acid (2500 mg orally during 12 hr) and pyridoxine (300 mg orally twice daily for seven days) on the excretion of urinary 2,3-dinor-6-ketoprostaglandin F1alpha, 11-dehydrothromboxane B2 and leukotriene E4, the markers of systemic prostacyclin, thromboxane A2 and cysteinyl leukotriene production, respectively, were investigated in healthy male ...

BACKGROUND: The aim of the present study was to assess luminal nitric oxide (NO) levels in the oesophagus during baseline and acidic conditions and to clarify the sources of such oesophageal NO formation. METHODS: Healthy volunteers received an intra-oesophageal infusion of either HCl (100 mM) or NaCl (50 mM) on ...

The first three transmembrane segments (M1-M3) of human nicotinic acetylcholine receptors (nAChRs) have been implicated in determining the efficacy of nicotine by studies of alpha3/alpha4 subunit chimeras. Nicotine has full efficacy on the alpha4beta2 nAChR and partial efficacy on the alpha3beta2 nAChR. Now, we have exchanged individually three amino acids ...

A new single walled carbon nanotubes (SWCNTs) purification procedure has been developed; it consists in a combination of air treatment and acid microwave digestion leading to a high purity SWCNTs material; the procedure reaches high metal removal percentages and the operation time is drastically reduced compared to conventional acid reflux ...

BACKGROUND: Effective intra-oesophageal acid suppression can be achieved with lansoprazole. The daily dosage could be influenced by the presence of hiatal hernia. AIM: To assess the lansoprazole daily dosage required to normalize oesophageal acid exposure in patients with and without hiatal hernia. METHODS: Fifty patients with complications or atypical manifestations ...

In Saccharomyces cerevisiae the nicotinic acid moiety of NAD+ can be synthesized from tryptophan using the kynurenine pathway or incorporated directly using nicotinate phosphoribosyl transferase (NPT1). We have identified the genes that encode the enzymes of the kynurenine pathway and for BNA5 (YLR231c) and BNA6 (YFR047c) confirmed that they encode ...

We report on the selective determination of tryptophan, using a carbon paste electrode coated with an overoxidized polypyrrole film. Out of 21 protein amino acids, only tryptophan and tyrosine exhibited an oxidative voltammetric response with this electrode. Tryptophan, which was preferentially concentrated to the electrode under an open circuit condition, ...

OBJECTIVE: Gastroesophageal reflux disease (GERD) plays a major role in the development of Barrett's esophagus. Recently, we demonstrated that duration of esophageal acid exposure in the distal esophagus correlates with the length of Barrett's mucosa. The aim of this study was to determine whether there is a relationship between the ...

The ability of cyanobacteria to produce the phytohormone indole-3-acetic acid (IAA) was demonstrated. A colorimetric (Salkowski) screening of 34 free-living and symbiotically competent cyanobacteria, that represent all morphotypes from the unicellular to the highly differentiated, showed that auxin-like compounds were released by about 38% of the free-living as compared to ...

Measures directed at improving the skin barrier function are thought to be effective in preventing reexacerbation of atopic dermatitis, but direct proof of a prophylactic effect of emollients has been elusive. In the present study, the atopy patch test has been employed as a model for the initiation phase of ...

Between 1990 and 1999, SO4(2-) deposition in northern Sweden decreased by over 50%. To determine if a corresponding amelioration of stream acidity has occurred, we analyzed trends in anthropogenically driven episodic acidification in five streams during the same time period, using the Boreal Dilution Model (BDM) (Bishop, K. H.; Laudon, ...

In our previous studies, interleukin-8 (IL-8) was labeled with (99m)Tc using hydrazinonicotinamide (HYNIC) as bifunctional coupling agent and tricine as coligand. This preparation showed excellent characteristics for imaging of infection in a rabbit model of soft-tissue infection. In the present study, the propylaldehyde hydrazone formulation of HYNIC was introduced to ...

An enzyme of Ralstonia/ Burkholderia strain DSM 6920 catalyzing the initial hydroxylation of 6-methylnicotinic acid at position 2 was purified to apparent homogeneity. It also catalyzed the unusual conversion of nicotinic acid to 2-hydroxynicotinic acid and was therefore designated as nicotinic acid dehydrogenase (NDH). Native NDH had a molecular mass ...

Organic acid anhydrides (OAAs) have considerable economic importance due to their extensive use in the production of alkyd, epoxy, and polyester resins. Occupational exposure to OAAs has been associated with a variety of health effects, which may be classified into two major categories of direct toxicity/irritant and hypersensitivity. The hypersensitivity ...

BACKGROUND & AIMS: To explore mechanisms whereby acid reflux might contribute to carcinogenesis in Barrett's esophagus (BE) we studied: (1) the effects of acid on the mitogen-activated protein kinase (MAPK) pathways, cell proliferation, and apoptosis in a Barrett's adenocarcinoma cell line (SEG-1); and (2) the ability of acid to activate ...

Quinolinic, picolinic, and nicotinic acids and nicotinamide are end products of the kynurenine pathway from l-tryptophan and are intermediates in the biosynthesis of nicotinamide adenine dinucleotide. These compounds are involved in complex interrelationships with inflammatory and apoptotic responses associated with neuronal cell damage and death in the central nervous system. ...

Time-series studies have shown that the lag time between elevated particulate air pollution (PM) and increases in cardiovascular-related hospital admissions and death is very short 1 d or less. If PM does cause serious cardiovascular effects shortly after exposure, one would expect to see some physiological change during exposure. In ...

To determine the relationship between Barrett's esophagus (BE) and features of gastroesophageal acid reflux, 24 h esophageal pH monitoring was performed in 90 patients. The patients were divided into 3 groups: 31 subjects with BE, 21 with mild esophagitis and 38 with severe esophagitis. The following parameters were evaluated: the ...

We have measured the components of the throughfall under fir trees (Abies firma) in the field around Mt. Oyama, where the forest appears to be declining, for the period 1994-1998. Exposure experiments of a simulated acid fog to fir twigs were performed under field conditions. There was a similarity between ...

The role of duodenogastroesophageal reflux (DGER), once erroneously termed "bile reflux," in causing esophageal mucosal damage has been an area of interest in both animal and human studies. However, because of the lack of appropriate techniques to accurately measure DGER, extrapolation of findings from animal studies to humans has been ...

Gastroesophageal reflux (GER) is a potential trigger of asthma. The esophagus and lung interact through a variety of mechanisms. Esophageal acid-induced bronchoconstriction can be provoked by a vagally mediated reflex, whereby acid in the distal esophagus produces airway responses; by neural enhancement of bronchial reactivity, whereby esophageal acid augments airway ...

It has been proposed that free radicals are involved in the pathogenesis of esophageal mucosal damage induced by acid and pepsin. Recent data have suggested that nitric oxide (NO) is involved in the mucosal defense of the esophagus and that superoxide anion plays a minor role in low-grade esophagitis. To ...

BACKGROUND AND AIMS: The pulmonary symptoms of patients with lung disease may be ascribed to gastro-oesophageal reflux although a causal relationship between acid reflux and coughing or wheezing has not been proved. Does cough cause reflux or does reflux cause cough? The aim of this study was to evaluate 24 ...

PURPOSE: The usefulness of intraesophageal monitoring of bilirubin, in diagnosing gastroesophageal reflux, was studied. PATIENTS AND METHODS: Bilirubin concentration and pH at 5 cm oral and anal to the esophagogastric junction were monitored for 24 hours in 19 patients with reflux esophagitis. The duration of bilirubin presented and pH less ...

Although visceral hypersensitivity is thought to be important in generating symptoms in functional gastrointestinal disorders, the neural mechanisms involved are poorly understood. We recently showed that central sensitization (hyperexcitability of spinal cord sensory neurones) may play an important role. In this study, we demonstrate that after a 30-min infusion of ...

BACKGROUND: Acid reflux can elicit non-cardiac chest pain (NCCP), possibly through altered visceral sensory or autonomic function. The interactions between symptoms, autonomic function, and acid exposure are poorly understood. AIM: To examine autonomic function in NCCP patients during exposure to oesophageal acid infusion. SUBJECTS AND METHODS: Autonomic activity was assessed ...

OBJECTIVES: The development of reflux esophagitis in humans is a process resulting from esophageal exposure to refluxed gastric contents. There is no doubt that damage to the esophageal epithelium requires exposure to gastric acid; however, the role of refluxed pepsin as contributor to this damage seems to be underappreciated. METHODS: ...

Application of citric acid/acetic anhydride reagent (CAR), a colour reagent selective for tertiary amines in solution, improves detection of abused tertiary amino drugs on the TLC plate. The plate is pretreated by a brief immersion in phosphoric acid/acetone solution to suppress colouration. After suppressing, the plate is sprayed with CAR ...

PURPOSE: To determine whether exposure of sclera to latanoprost acid alters transscleral permeation by FGF-2. METHODS: Pieces of human sclera were isolated from donor eyes after death, placed in organ culture, and exposed to 50 to 200 nM latanoprost acid or vehicle for 3 days. Transscleral permeability was then assessed ...

Chronic daytime and noctural acid reflux causes mucosal damage, heartburn, and other symptoms of GERD. The esophageal complications of GERD result from long-term exposure of the esophagus to acid. Extraesophageal GERD complications, such as laryngitis and asthma, develop when some of the acidic refluxate in the proximal esophagus enters the ...

Particulate sulphates, including sulphuric acid (H2SO4), are important components of the ambient aerosol in some areas and are regarded as air pollutants with potentially important human health effects. Challenge studies suggest little or no effect of H2SO4 exposure on lung function in asthmatic adults, although some epidemiological studies demonstrate an ...

BACKGROUND: Reflux of duodeno-gastric juice into the oesophagus appears to be involved in the pathogenesis of both reflux oesophagitis and oesophageal adenocarcinoma. Although proton pump inhibitors have been shown to decrease acid reflux and heal oesophagitis, their effect on biliary reflux and motility is less clear. AIM: To investigate whether ...

BACKGROUND: Cisapride has been shown to have not only prokinetic effects, but also salivary stimulating effects. Both of these mechanisms play an important role in the acid clearance of the oesophagus. AIM: To access the efficacy of cisapride in facilitating acid clearance in patients with symptomatic gastro-oesophageal reflux disease. METHODS: ...

Heartburn occurs in the presence as well as the absence of acid reflux. We searched for a motor correlate of heartburn. Twelve subjects with heartburn were studied with 24-h synchronized pressure, pH, and high-frequency intraluminal ultrasound (HFIUS) imaging of the esophagus. The HFIUS images were analyzed every 2 s for ...

Laryngopharyngeal reflux has been proposed as a possible cause of sudden infant death syndrome (SIDS). We investigated the efferent laryngeal and diaphragmatic responses to acid exposure on the laryngeal mucosa using a neonatal canine model. Electromyographic (EMG) recordings from the thyroarytenoid muscle and the diaphragm were measured with hooked-wire electrodes. ...

Nitrates and calcium channel blockers (CCBs) have been shown to decrease lower esophageal sphincter pressure and theoretically may precipitate or aggravate gastroesophageal reflux. Thus, the authors hypothesized that patients who receive these agents would have greater use of acid-suppressive drug use, defined as histamine2 antagonists or proton pump inhibitors. A ...

Nicotinic acid and its related compounds are well known lipid lowering agents but the use of nicotinic acid in clinical practice is limited because of its side effects. To reduce the unwanted effects, new derivatives of nicotinic acid have been synthesized and tested in control and pathological animals for their ...

A multi-vitamin auxotroph, Torulopsis glabrata strain WSH-IP303, which can use ammonium chloride as a sole nitrogen source for pyruvate production, was selected. To optimize pyruvate yield and productivity, a simple but useful, orthogonal design method, was used to investigate the relationship between thiamine, nicotinic acid, pyridoxine, biotin, and riboflavin. Thiamine ...

BACKGROUND & AIMS: Nonacid reflux may explain symptoms in acid-suppressed patients. Simultaneous intraesophageal impedance and pH measurement was used to evaluate the frequencies of postprandial acid and nonacid reflux before and after omeprazole administration. METHODS: Twelve heartburn patients underwent two 2-hour studies of intraesophageal impedance and pH in the right ...

The effects of pyrazinamide on the metabolism of tryptophan to niacin and of tryptophan to serotonin were investigated to elucidate the mechanism for pyrazinamide action against tuberculosis. Weanling rats were fed with a diet with or without 0.25% pyrazinamide for 61 days. Urine samples were periodically collected for measuring the ...

BACKGROUND & AIMS: Gastroesophageal reflux can be acid, nonacid, pure liquid, or a mixture of gas and liquid. We investigated the prevalence of acid and nonacid reflux and the air-liquid composition of the refluxate in ambulant healthy subjects and patients with reflux disease (GERD). METHODS: Twenty-four-hour ambulatory recordings were performed ...

OBJECTIVES: The aim of this study was to demonstrate that integrated esophageal and gastric acidity values, calculated from 24-h pH recordings, can provide more precise quantitative temporal data than the conventional pH parameters historically associated with gastroesophageal reflux disease (GERD) investigations. METHODS: Esophagogastroduodenoscopy results and pH tracings from 20 GERD ...

Gastroesophageal reflux disease (GERD) is a condition where acid contents of the stomach are regurgitated into the oral cavity, which results in continual exposure of the teeth to these acids. Knowledge of the relationship between GERD and dental erosion enables the appropriate diagnosis and treatment of the underlying medical condition ...

BACKGROUND: Postprandial gastric distention is frequently associated with transient lower esophageal sphincter relaxation and gastroesophageal reflux (GER). Since the role of nutrient perfusion into the jejunum in inducing GER is not well understood, we studied the effect of jejunal feeding on GER through a percutaneous gastrojejunal tube in patients with ...

Exposure to diesel exhaust is a suspected risk factor for human lung cancer. The carbonaceous core of the soot particles found in diesel exhaust and the condensed organic compounds adsorbed (or bound) onto the surface of the particles are both possible contributors to this suspected risk. The extent and rate ...

Boron is widely used in industrial materials, most frequently as the salt borax. Systemic exposure (eg, ingestion) to boron in boric acid been associated with reversible toxic alopecia among other manifestations. There is scant clinical literature on alopecia caused by topical exposure to boron. We observed a series of 3 ...

The rate constants for transfer of a homologous series of nicotinic acid esters from oil vehicles to aqueous buffer phases were determined using a rotating dialysis cell. The chemical stability of butyl nicotinate has been investigated at 60 degrees C over pH range 0.5--10. Maximum stability occurs at pH 4--5 ...

Barrett's oesophagus, a significant complication of gastro-oesophageal reflux disease (GERD), is the single most important risk factor for oesophageal adenocarcinoma. The strong association between Barrett's oesophagus and chronic GERD suggests that abnormal oesophageal acid exposure plays an important role in this condition. The progression of Barrett's oesophagus from specialized intestinal ...

Patients who present with uncontrolled esophageal acid reflux symptoms require endoscopy to determine the presence or absence of ulcers and stenoses, acid reflux testing to determine if acid reflux is present, and manometry to evaluate esophageal peristalsis and spastic states. These studies are usually done in stages, at separate times. ...

BACKGROUND: Gastro-oesophageal reflux disease (GORD) plays a major role in the development of Barrett's oesophagus. However, it has yet to be elucidated what factors determine the length of Barrett's mucosa in each individual patient. AIMS: To determine if there is a correlation between oesophageal acid exposure and the length of ...