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At least 541 records · Page 30Linked to original sources
PubMed1980

Non-specific broncho-reactivity obtained with an ultrasonic aerosol of distilled water.

A mist of distilled water obtained by means of powerful high density ultrasonic device has been used as nonspecific challenge test for assessing bronchial hyperreactivity in asthmatics. It looks an easier and/or more physiologic stimulation when compared with the nebulisation of other substances such as histamine, acetylcholine, methacholine, carbachol, citric acid, prostaglandins. Furthermore, this test shows good correspondence to the history of fog-induced asthma. In ten normal subjects the ultrasonic mist of H2O doesn't produce any functional change, while in thirteen asthmatic patients it results in a clear-cut bronchoconstriction, with a maximal evidence within 10 minutes and a subsequent decrease up to 30 minutes. Premedication with propranolol doesn't change the negativity of the test in normal subjects. Ultrasonic mist of saline doesn't determine any remarkable bronchoconstriction in asthmatics. In forty asthmatics a trial has been then carried out on prevention of water-induced bronchoconstriction by different pharmacologic means. Ipratropium fails to protect significantly the patients, while Disodium-cromoglycate, Salbutamol and prostaglandins E reduce significantly the entity of the so induced bronchospasm. These observations support the hypothesis of a mast cell mediated mechanism and disprove the vagal contribution to this type of bronchial challenge.

Adult↗
PubMed1984

Comparison of ultrasonically nebulized distilled water and hyperventilation with cold air in asthma.

To assess the potential value of brief non-pharmacologic challenge tests in the measurement of bronchial responsiveness and to investigate whether the responses are induced by similar mechanisms, we carried out comparative five-minute inhalation challenges with ultrasonically nebulized distilled water and cold air hyperventilation in nine asthmatic subjects. Decrements in FEV1 following both challenges were closely correlated (r = 0.885) and ranged from 8% to 59% of baseline following challenge with the former and from 6% to 59% following the latter. Each method was therefore equally effective in demonstrating bronchial hyperresponsiveness. Moreover, the strong correlation between the responses to both challenges coupled with previous observations suggests that the two stimuli may act by similar mechanisms.

Administration, Intranasal↗
PubMedDate not supplied

Recent advances in cleanup of fats by sweep co-distillation. Part 2. Organophosphorus residues.

This paper describes the isolation of 5 organophosphorus residues in beef fat by a commercial sweep co-distillation unit (Unitrex). The operating conditions specified 223 degrees C and nitrogen flow at 230 mL/min. Recoveries of chlorpyriphos, monodechlorchlorpyriphos, bromophos-ethyl, debromobromophos-ethyl, and ethion ranged from 84 to 99%, with coefficients of variation between 3 and 5%.

Animals↗
PubMed1983

Determination of styrene migration from food-contact polymers into margarine, using azeotropic distillation and headspace gas chromatography.

Migration studies were conducted to determine the quantity of styrene that migrates from polymers into fatty foods, specifically margarine. Azeotropic distillation was used to isolate styrene from the margarine. Headspace gas chromatography with a Chromosorb 104 column and a flame ionization detector was used for quantitation. The quantitation limit for the method was about 25 ppb (wt/wt) styrene in margarine. On the average, greater than 90% of the styrene was recovered. Several commercial margarines were examined. The method and results of the migration studies are presented. There was no detectable migration of styrene into margarine.

Chromatography, Gas↗
PubMed1983

[Presence of Caulobacter genus in distilled water].

Schizomycetes have been examined by optical microscope at monochromatic reflected light system, after treatment with a ferrotannic ammoniacal silver solution according to Blenden and Goldberg (1). The bacterial preparations appeared to contain some cellular forms which because of their morphology, could belong to the family Caulobacteriaceae. Further investigations showed that these Caulobacters derived from the distilled water used to prepare the solutions.

Gram-Negative Aerobic Bacteria↗
PubMedDate not supplied

Recent advances in cleanup of fats by sweep co-distillation. Part 1: Organochlorine residues.

A redesigned fractionation tube has resulted in development of a new, commercial sweep co-distillation unit. It is compact, reliable, cost-efficient, and permits cleanup of pesticides in up to 10 fat samples simultaneously. Recovery of several organochlorine residues (HCB, alpha-BHC, lindane, heptachlor epoxide, dieldrin, p,p'-DDE, p,p'-DDD, p,p'-DDT) at ppm and ppb levels in meat (beef) fat are 83-105%, with coefficients of variation between 4 and 6%. Cleaned up extracts are quantitated by gas chromatography using an electron capture detector with a vitreous silica capillary column containing a medium polarity bonded phase.

Animals↗
PubMedDate not supplied

Effects of ultrasonically nebulized distilled water on respiratory resistance and breathing pattern in normals and asthmatics.

The purpose of this study was to analyze changes in respiratory resistance (Rrs) and breathing pattern in normal and asthmatic subjects after exposure to ultrasonically nebulized distilled water (UNDW). After measurement of baseline Rrs and breathing pattern, ten normals inhaled UNDW for 30, 60, 120, 240 and 480 s administered at 15 min intervals. After the 480 s exposure, subjects inhaled two puffs of metaproterenol. Rrs was measured immediately before and after each exposure to UNDW and after metaproterenol while breathing pattern was continuously monitored. Ten asthmatics were exposed to UNDW and metaproterenol in a similar time sequence, but the durations of exposure to UNDW were 15, 30, 60, 120 and 240 s. Mean (+/- SD) and frequency histograms of minute ventilation (VE), tidal volume (VT), frequency, inspiratory time, fractional inspiratory time, mean inspiratory flow (VT/TI) and end-expiratory level at baseline were compared to values after each exposure to UNDW and after metaproterenol. All subjects experienced laryngeal irritation or cough during the exposure. In normals, there were no changes in Rrs or any of the components of breathing pattern. In asthmatics, 15 and 30 s exposures produced no changes in Rrs or breathing pattern. With subsequent longer exposures, mean Rrs showed a stepwise significant increase, along with parallel increases of VT/TI and end-expiratory level. VE increased after 60 and 120 s exposure, but reached a plateau after 240 s exposure despite continued increase in Rrs.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1982

[On the content of polycyclic aromatics in middle distillates].

The concentrations of polycyclic aromatics determined up to now in Diesel fuel and light fuel oil are between five percent by weight for all and 0.02 percent by weight for nearly a dozen individuals. These results are contrasted and commented. It is not adequate to the problem to consider only a few polycycles in the analysis and to neglect practical completely alkylated derivates. Already for this reason the results with the small concentrations are not regarded to be characteristics for middle distillates. Probably insufficient analytics are also responsible for the determination of the low contents.

Fuel Oils↗
PubMed1982

Dna synthesis in the urinary-tract epithelium of the rat induced by laparotomy and by intraperitoneal injection of distilled water, physiological saline and lycopodium spores.

The tritiated thymidine labelling index (LI) of the epithelium of the ureters and urinary bladder of young male Wistar rats is substantially increased 18 h after a simple laparotomy incision. A similar highly significant increase (P less than 0.001) has been observed after a single i.p. injection of various materials, including (a) distilled water, (b) 0.5% glycogen in physiological saline, and (c) 1% suspension of lycopodium spores in physiological saline. In each instance an aseptic inflammatory response develops in the peritoneal cavity. Reasons are given supporting the concept that a mitogen is produced from a constituent of the inflammatory exudate in the peritoneal cavity and that the factor reaches the affected epithelium by direct diffusion.

Animals↗
PubMed1980

Comparison of the acute effects of sugar cane distillates and ethanol in mice.

The acute effects of 4 different brands of the most popular Brazilian alcoholic beverage, the so called "cachaças" (distilled product of sugar cane), were measured through the loss of the righting reflex and the rotarod test. The effects induced by the cachaças were greater than it could be predicted through the ethanol content alone.

Alcoholic Beverages↗
PubMed1994

Inhibition of tumor cell growth by low-boiling-point-saturated fatty acids isolated by molecular distillation and reversed phase liquid chromatography of hydrolysates of uncytotoxic wool grease secreted from sheep sebaceous gland.

We showed that massive growth of mouse Ehrlich ascites carcinoma (EAC) cells was not inhibited by wool grease secreted from the sheep sebaceous gland, whereas wool fatty acids separated by saponification of wool grease was growth-inhibitory. We then fractionated wool fatty acids into 9 fractions using molecular distillation (80-200 degrees C; 1 x 10(-2) mmHg) and found a marked antitumor activity in a low-boiling-point (< 80 degrees C) fraction (MW 200-300; C10-C20), which was further separated by reversed phase liquid chromatography on an octadecylisilica gel column, resulting in 5 fractions. The second most hydrophobic fraction (C8Si-4) obtained was the most growth-inhibitory to EAC cells cultured or implanted into mice, more marked than the antitumor glycopeptide bleomycin. C8Si-4 was suggested to be a mixture of a normal-chain C16-saturated fatty acid and two branched-chain kinds of saturated C16-iso- and C19-anteiso-fatty acids without hydroxyl groups according to gas chromatography-mass spectrographic analysis. Thus low-boiling-point saturated fatty acid moieties in some wool grease molecules were shown to become growth-inhibitory in vitro and in vivo only after released in the free acid form by esterolysis.

Animals↗
PubMed1994

Comparison of bronchial reactivity to ultrasonically nebulized distilled water, exercise and methacholine challenge test in asthmatic children.

We studied the responses to ultrasonically nebulized distilled water (UNDW) challenge, exercise challenge and methacholine challenge in asthmatic children. Fifty-four asthmatic and fourteen nonasthmatic control children participated in this study. The UNDW inhalation test was by the methodology described by Anderson. The average output of water was approximately 3.0 mL/min (SD = .1) and inhalation times were 30 seconds, one minute, two minutes and four minutes. Some subjects performed exercise challenge on a bicycle ergometer and methacholine challenge by an Astrograph technique. Twenty-three of 54 asthmatic patients (42.6%) and none of the controls showed a fall in FEV1 greater than 20% with UNDW challenge. The fall in FEV1 with UNDW correlated with that induced by exercise challenge (r = .89) and Log Dmin, which may reflect bronchial sensitivity (r = .70). Our method is not sensitive enough for detecting bronchial hyperresponsiveness in all asthmatic children. Bronchoconstriction induced by UNDW has a similar mechanism of action as exercise and methacholine.

Administration, Inhalation↗
PubMed1995

Effect of inhaled nedocromil sodium therapy on blood gas changes in children challenged with ultrasonically nebulized distilled water. A comparison of 8 mg versus 16 mg daily dose.

Changes in time course of blood partial pressures of oxygen (PtcO2) and carbon dioxide (PtcCO2) before, during and after challenge with ultrasonically nebulized distilled water (UNDW) were evaluated in 22 children with mild asthma in basal conditions, and after 8 weeks of therapy with inhaled nedocromil sodium at a daily dosage of 8 or 16 mg. PtcO2 and PtcCO2 were followed using transcutaneous O2 and CO2 monitoring system. All asthmatic subjects presented a significant decrease in PtcO2 and/or PtcCO2 (> 20% basal value) during or after challenge. After therapy, the decrease in PtcO2 and PtcCO2 was normalized in the group treated with 16 mg/day, whereas only a partial yet significant reduction in the decrease of O2 and CO2 was observed in the group assuming 8 mg/-day. These data indicate that inhaled nedocromil is effective in treating bronchial hyperresponsiveness in childhood and that the dose required to achieve this effect is of 16 mg/day.

Administration, Inhalation↗
PubMed1996

[Effects of inhaled anticholinergic agents and beta 2-agonists on distilled water induced cough in patients with chronic cough].

The purpose of this study was to evaluate the usefulness of ultrasonically nebulized distilled water (UNDW) inhalation for assessing cough receptor sensitivity and also the effects of inhaled anticholinergic agents and beta 2-agonists on the number of coughs induced by the UNDW inhalation in patients with chronic cough. All patients were non-smokers and had neither bronchial hyperreactivity nor atopic status. We studied the effects of inhaled oxitropium bromide (300 micrograms) and fenoterol hydrobromide (600 micrograms) on the number of coughs induced by UNDW inhalation for 3 minutes in 9 patients with chronic cough and the effects of inhaled fenoterol hydrobromide (400 micrograms) on the number of coughs induced by UNDW inhalation for 1 minute in 8 patients with chronic cough using a randomized, double-blind, cross-over method. There was no significant difference in pulmonary function test results before and after UNDW inhalation. In both the 3-minute and 1-minute UNDW inhalation studies, the number of coughs was greater in the patients than in normal subjects. Patients with chronic cough may have a high level of cough sensitivity, inhaled fenoterol significantly reduced the number of coughs in the patients in both the 3-minute and 1-minute UNDW inhalation studies (p < 0.05). However, compared with control, inhaled oxitropium did not reduce the number of coughs caused by the 3-minute UNDW inhalation in the patients. Tachyphylaxis was observed in normal subjects in the 3-minute UNDW inhalation study when repeated at a 30-minute interval. We conclude that 1-minute UNDW inhalation method may be safe and useful for measuring cough receptor sensitivity of patients with chronic cough and that inhaled beta 2-agonists may have an inhibitory effect on cough induced by irritation of cough receptors through unknown mechanisms other than the bronchodilator effect.

Administration, Inhalation↗
PubMed1976

Gas chromatographic determination of micro amounts of cyanide residues in wines, distilled liquors, and other alcoholic beverages.

A gas chromatographic method for the determination of cyanide residues in alcoholic beverages has been developed from procedures previously reported for application to water samples. Quantitatively isolating HCN from alcoholic beverages presented difficulties not encountered with aqueous solutions, particularly in the presence of S02 in the sample. HCN was liberated from the acidified sample by heating at 70 degrees C, flushed into an NaOH absorber solution, converted to cyanogen bromide (CNBr), extracted into diisopropyl ether, chromatographed on a Porapak Q column, and detected by an electron capture detector. S02 that is present in most wines interfered with the bromination step and caused low recoveries. This interference was eliminated by initially converting any cyanide present in the sample to the stable mercuric cyanide salt and then purging the acidified sample solution of all S02. The Hg(CN)2 present was then dissociated by adding KI and the analysis proceeded as previously described. Mean recoveries of 80-97% were obtained for 2-20 mug cyanide from replicate analyses of spiked samples of distilled liquors free of S02. The relative standard deviations ranged from 6.1 to 11.1%. Mean recoveries of 65 to 91% were obtained in the same range of cyanide from replicate analyses of spiked wine samples known to contain S02, with relative standard deviations ranging from 0.8 to 10.2%. The limit of detection was 0.2 mug HCN.

Alcoholic Beverages↗