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At least 469 records · Page 26Linked to original sources

PubMed2001

Change in endotracheal tube cuff pressure during nitrous oxide anaesthesia: a comparison between air and distilled water cuff inflation.

In this prospective, randomized controlled trial, changes in endotracheal tube cuff pressure were studied in 60 patients undergoing elective surgery under general anaesthesia with nitrous oxide and oxygen. The cuffs were inflated with either air or distilled water. The mean pressure in the air-filled cuffs increased steadily throughout the procedure, reaching 47.5 +/- 7.3 cmH2O at one hour compared with 31.6 +/- 2.4 cmH2O mean pressure in the water-filled cuffs. The pressure and the rate of rise in cuff pressure were significantly lower (P<0.05) in the water-filled cuffs throughout the hour of study. When an endotracheal tube cuff is distended with water, the rise in cuff pressure during nitrous oxide anaesthesia is lower than that of an air-filled cuff.

Adolescent↗

PubMed1988

Comparative dermal carcinogenesis of shale and petroleum-derived distillates.

Ten test materials derived from petroleum or hydrotreated shale oils were applied 3 times/week for up to 105 weeks to the shaved skin of 25 male and 25 female C3H/HeN mice per group. Mineral oil and benzo(a) pyrene (0.15%) were control materials. Clinical observations were recorded during the study. At death, histopathologic examination was conducted on skin, internal organs and any gross lesions. Exposures to some materials were ended midway in the study due to severe irritation. Chronic toxicity of all materials was limited to inflammatory and degenerative skin changes. Significant increases over control incidence of skin tumors (squamous cell carcinoma and fibrosarcoma) occurred with both petroleum and shale-derived naphtha (21%, 50%), Jet A (26%, 28%), JP-4 (26%, 50%), and crude oils (84%, 54%). Severely hydrotreated shale oil and petroleum and shale-derived diesel distillates were not considered tumorigenic. Results indicate that toxicity of comparable petroleum and shale-derived fractions was qualitatively similar and confirm earlier findings that hydrotreating reduces or eliminates carcinogenicity of raw shale oil.

Animals↗

PubMedDate not supplied

A 90-day toxicity study of the effects of petroleum middle distillates on the skin of C3H mice.

Petroleum middle distillates (PMDs) elicit skin tumors in mouse epidermal carcinogenesis studies. The response is characterized by a long latency with only a small percentage of animals developing tumors. Although the carcinogenic activity of certain other petroleum hydrocarbons largely depends upon the presence of polycyclic aromatic hydrocarbons (PAHs), many PMDs contain relatively low concentrations of PAHs. PMDs are also irritating to mouse skin, and chronic irritation may be involved in the development of skin tumors. This study was conducted to investigate the patterns of cutaneous irritation elicited by topical application of PMDs having compositional differences. The three PMDs selected for study were a steam cracked gas oil (SCGO), a lightly refined paraffinic oil (LRPO), and a jet fuel (JF). Male C3H/HeNCr1BR mice (25/group) were treated topically (37.5 microliters 2x/week for 13 weeks) with 10%, 50% or 100% (undiluted) concentrations of each PMD. Catalytically cracked clarified oil (CCCO, 10%), a potent carcinogen to mouse skin, was also tested. The vehicle was a noncarcinogenic mineral oil with a viscosity of 90 SUS. Cutaneous changes were evaluated by gross observations and light microscopy. Cutaneous irritation was the only significant toxic response in this study. Neither the vehicle nor any of the 10% PMD concentrations produced significant cutaneous irritation. The 10% CCCO and 50% PMD treatments all elicited slight to moderate proliferative and inflammatory changes in mouse skin. Ulcers were also observed microscopically in mice treated with 10% CCCO and 50% SCGO. The 100% SCGO treatment produced evidence of necrosis on Days 1-7 but not later in the study despite continued treatment. In contrast, the irritating effects of 100% LRPO were not evident until 2-3 weeks of study, and at study completion were characterized by moderately severe inflammatory and proliferative changes. The effects of 100% JF were qualitatively similar to 100% LRPO but less marked. Thus, the SCGO caused a different pattern of cutaneous responses than either LRPO or JF. The possible relationships of these cutaneous changes to epidermal carcinogenesis are being studied further.

Animals↗

PubMed1999

Toxicosis in cattle from concurrent feeding of monensin and dried distiller's grains contaminated with macrolide antibiotics.

Consumption of monensin-containing feed contaminated with macrolide antibiotic residues resulted in the death of cattle from multiple feedlots in south-central Kansas. Cattle were fed milo dried distiller's grains (DDG) with solubles from a common source in conjunction with the ionophore antibiotic, monensin. Deaths occurred as early as 72-96 hours after feeding and were preceded by either no premonitory signs or 1 or more of the following: anorexia, depression, dyspnea, locomotor deficits, and recumbency. Significant gross lesions were pulmonary and mesenteric edema, hepatomegaly, and generalized myocardial and skeletal muscle pallor that was confirmed histologically as acute myodegeneration and necrosis. Other significant histologic lesions included centrolobular hepatocellular necrosis, congestion, and pulmonary interstitial and alveolar edema with fibrin exudation. Animals that survived beyond 6 weeks had poor weight gain and coalescing foci of myocardial fibrosis with residual myocardial degeneration. Analysis of trace mineral supplements for monensin were within the manufacturer's label range. The DDG samples from affected feedlots had 50-1,500 ppm of erythromycin, clarithromycin, and related macrolide antibiotic analogues, which originated in the alcohol residue. In a preliminary feeding trial, cattle fed this contaminated DDG in combination with monensin had clinical signs and died with gross and histologic findings comparable to those of the field cases. Even though rations supplemented with the contaminated DDG contained approved levels of monensin, the clinical and postmortem findings were consistent with those expected for monensin toxicosis. The presence of macrolide antibiotic residues in the contaminated feed appeared to affect the biotransformation of otherwise nontoxic levels of monensin, leading to clinical ionophore toxicosis.

Animal Feed↗

PubMed1991

Stability of labetalol hydrochloride in distilled water, simple syrup, and three fruit juices.

Labetalol hydrochloride (HCl) is an effective antihypertensive drug. It is available in a tablet dosage form, which may be difficult to administer to geriatric and pediatric patients. The tablets can be suspended in various liquid vehicles, but its stability under these conditions is unknown. The objective of our study was to determine the stability of labetalol HCl in five liquid vehicles, in both plastic and glass prescription bottles, over a four-week period at room temperature and under refrigeration. Labetalol HCl tablets (Trandate, Glaxo) were triturated, and suspended in distilled water, simple syrup, apple juice, grape juice, and orange juice to approximate concentrations of 7-10 mg/mL. After filtration, the liquids were stored in five amber, plastic prescription bottles, and five amber, glass prescription bottles at 4 degrees C and 23 degrees C. The samples were collected at 0, 24, and 72 hours, and 1, 2, and 4 weeks after initiation of the study. Labetalol HCl was measured by an HPLC method. Because there was no substantial change in labetalol HCl concentration during the study period, the tablet dosage from can be reformulated, stored, and administered to elderly or pediatric patients as a liquid dosage form.

Carbohydrates↗

PubMed2001

Instillation of 3% hydrogen peroxide or distilled vinegar in urethral catheter drainage bag to decrease catheter-associated bacteriuria.

Patients with indwelling catheters acquire urinary tractinfections ata rate of 5% perday. After 30 days of catheterization, there is a 78% to 95% incidence of bacteriuria, despite the use of meticulous catheter care. Research studies on reducing the development of bacteriuria have focused on the propagation of bacteria within the catheter drainage bag. This research proposal sought to determine the effects of instillation of 3% hydrogen peroxide versus distilled vinegar in urethral catheter drainage bags to decrease bacteriuria in 20 long-term catheterized patients. Baseline urine cultures for control and test mediums showed no significant difference in rates of bacteriuria. However, urine cultures obtained at the 48-hour interval showed significant reduction in bacteriuria in urinary bags irrigated with vinegar The implications this study has for nursing practice include a needforfurther research using a larger number of subjects and a need for improvements in the design of the catheter drainage system.

Acetic Acid↗

PubMed1997

Sustained protection against distilled water provocation by a single dose of salmeterol in patients with asthma.

The long-acting beta2-agonist salmeterol inhibits in vitro the release of inflammatory mediators up to 20 h. These mediators are involved in ultrasonically nebulized distilled water (UNDW)-induced bronchoconstriction. We investigated whether salmeterol provides prolonged protection against UNDW provocation and whether this effect was paralleled by its bronchodilator effects. Nineteen asthmatic patients (mean forced expiratory volume in one second (FEV1) 84.8% predicted, mean provocative concentration of histamine producing a 20% decrease in FEV1 0.65 mg x mL(-1)) participated in this randomized, double-blind, placebo-controlled crossover trial. After measuring baseline FEV1, patients inhaled 50 microg salmeterol or placebo by metered-dose inhaler. FEV1 was measured after 20 and 40 min, and UNDW provocations and FEV1 measurements were performed after 10, 20 and 34 h. Compared to placebo, salmeterol caused marked bronchodilatation from 20 min up to 20 h after inhalation. Salmeterol also provided more than 20 h of protection against UNDW provocation (still more than one doubling dose). Protection beyond the period of bronchodilatation did not occur. Eleven subjects had a significant reduction in provocative dose of UNDW causing a 20% fall in FEV1 (PD20,UNDW) values between 10 and 20 h, at a time when there was still persistent bronchodilation. No correlation existed between changes in FEV1 and changes in PD20,UNDW. From the equations of regression lines between FEV1 and corresponding PD20,UNDW values, it was calculated that only approximately 25% of the afforded protection was explained by bronchodilatation. In conclusion, a single dose of salmeterol induces both bronchodilatation and protection independently of this bronchodilation against a physiological bronchoconstrictor stimulus for more than 20 h.

Administration, Inhalation↗

PubMed1998

Longitudinal predictors of airway responsiveness to distilled water: the role of atopy and maternal smoke exposure.

Airway responsiveness is an objectively measurable clinical trait related to the presence of asthma. Although risk factors for this trait have been evaluated cross-sectionally, little is known about its longitudinal predictors. A population cohort of 539 children, aged 8 yrs at the start of follow-up, underwent 3-7 bronchial challenge tests spaced at 3-9 month intervals. Airway responsiveness was assessed by a single-step distilled water challenge. To investigate responsiveness as a continuous trait, the ratio of the postchallenge to prechallenge forced expiratory volume in one second was calculated. A child's repeated ratios were then regressed on the time of follow-up. The resulting child-specific regression coefficient was the outcome variable to assess longitudinal predictors of airway responsiveness (AR). Results were based on 2,267 repeated challenge tests, and indicated an overall decrease in responsiveness. Children with a diagnosis of asthma (mean+/-SD, longitudinal change in AR + yr(-1): -0.060+/-0.149), those with a positive skin-prick test (-0.018+/-0.106) and those with reported exposure to maternal smoking (-0.004+/-0.083) demonstrated increased airway responsiveness over time. All of these changes in airway responsiveness were found to be significant in multiple linear regression analysis (p<0.05). Stratified analysis further indicated that the effect of maternal smoking was observed primarily in nonatopic children and was greatest at an exposure level of > or =10 cigarettes x day(-1). In conclusion, atopy and exposure to maternal smoking can predict longitudinal change in childhood airway responsiveness.

Air Pollutants↗

PubMed2005

Airway protective reflexes evoked by laryngeal instillation of distilled water under sevoflurane general anesthesia in children.

To investigate how sevoflurane modifies airway protective reflexes in anesthetized children, we recruited patients younger than 12-yr-old for our study. Anesthesia was induced with inhaled sevoflurane in oxygen. The airway was managed with a laryngeal mask airway and the patient breathing spontaneously. Depending on the depth of anesthesia, the subjects were divided into two groups: Group 1 and Group 2 (1% and 2% of end-tidal sevoflurane concentration, respectively). Behaviors of the larynx were assessed mainly by the fiberscopic images of the larynx as well as respiratory flow and esophageal pressure. A small dose, 0.02 mL/kg of distilled water (minimum 0.2 mL) was instilled to the larynx through a channel of the scope to evoke an airway protective reflex from the larynx. The responses were categorized into passive (laryngeal closure, laryngospasm, and apnea) and active (cough, expiration reflex, and swallowing reflex) responses. Ten subjects were included in each group. In both groups, the primary responses were passive; however, in Group 1, active reflexes were also observed in 8 of 10 subjects; no subjects in Group 2 had active reflexes (P < 0.01). We concluded that, in children, the depth of general anesthesia with sevoflurane modified airway protective reflexes.

Anesthesia, General↗

PubMed1985

[Anti-inflammatory activity of the dry distillation tar of delipidated soybean (Glyteer) (1)].

The anti-inflammatory activity of the dry distillation tar of delipidated soybean (GL, 0.1 approximately 10%) was investigated by its topical application to mice, rats and guinea pigs; and the effects were compared with those of betamethasone 17-valerate (BV, 0.12%), ibuprofen (IP, 5%), phenylbutazone (PB, 5%) and flufenamic acid (FA, 5%), which were all prepared with the same ointment base. GL (1 approximately 10%) showed a concentration-dependent inhibition of the increased vascular permeability induced by histamine and bradykinin in guinea pigs. GL significantly inhibited rat paw edema induced by carrageenin, but in serotonin-induced paw edema, GL showed only a weak effect. GL also inhibited the erythema formation induced by ultra-violet rays, and the activity was equal to that of PB. The inhibitory potency of GL against the erythema formation induced by arachidonic acid in guinea pigs was equal to that of IP. It is suggested from these results that the mode of action of GL is similar to that of other acidic non-steroidal anti-inflammatory drugs. However, GL did not inhibit paper disk granuloma in rats. Furthermore, GL markedly inhibited the delayed-type hypersensitivity induced by picryl chloride, and the activity was stronger than that of IB, PB and FA. Here GL showed the mode of action seen with steroidal anti-inflammatory drugs. The present data provide evidence that GL applied externally possesses a potent effect as an anti-inflammatory drug.

Administration, Topical↗

PubMed2001

Characterization of the cellulose-binding ability of Geotrichum sp. M111 cells and its application to dehydration of the distilled waste of sweet potato shouchu.

The cellulose-binding ability of Geotrichum sp. M111 cells was investigated by the micro-tube method which gives an indication of the binding ability of M111 cells. The optimum pH value and temperature were 3-7 and below 50 degrees C, respectively, from measurement of the aggregation height for a mixture of cellulose powder and M111 cells. The binding constant of 0.3% for M111 cells to cellulose powder was obtained in a 20 mm citrate buffer of pH 5.0 at 30 degrees C. Aggregation was inhibited by such surfactants as sodium dodecylsulfate. The binding ability of M111 cells to cellulose fiber disappeared after a treatment with Driselase or Pronase E. This suggests that the binding ability might be related to the cell surface proteins. The dehydration rate of the distilled waste of sweet potato shouchu was accelerated by the addition of M111 cells. The analysis of dehydration by a linear viscoelastic model suggests that the acceleration effect might have been due to the space increase between cellulose fibers with the cell addition.

Cellulose↗

PubMed1997

Cardiovascular reflex mechanisms by topical instillation of capsaicin and distilled water into the larynx in anesthetized dogs.

Cardiovascular reflex mechanisms by topical laryngeal instillation of capsaicin (CAPS) or distilled water were evaluated in anesthetized chronic tracheostomized dogs. Both CAPS (10 micrograms/ml) and water instillation into the isolated upper airway caused a significant decrease in heart rate (P < 0.05) and a significant increase in blood pressure (P < 0.05) from the values before instillation under both spontaneous and controlled ventilation. The bradycardia was significantly reduced by atropine pretreatment (P < 0.05) and the hypertension was significantly decreased by phentolamine and propranolol pretreatments (P < 0.01). A higher concentration of CAPS (100 micrograms/ml) instillation considerably reduced the response to subsequent CAPS (100 micrograms/ml) instillation, whereas the response to water was sustained, indicating the desensitization of laryngeal CAPS-sensitive endings. All the reflex responses to CAPS and water were eliminated by topical anesthesia with lidocaine. It was concluded that the laryngeal cardiovascular reflex responses were mediated by the afferents such as the laryngeal CAPS-sensitive presumably C-fiber endings or water-responsive receptors and by both the parasympathetic and sympathetic nervous systems as efferents.

Administration, Topical↗

PubMed1999

The posterior nasal nerve plays an important role on cardiopulmonary reflexes to nasal application of capsaicin, distilled water and l-menthol in anesthetized dogs.

The sensory innervation of the cardiopulmonary reflexes to nasal application of capsaicin (CAPS), distilled water (DW) and l-menthol (LM) was studied in anesthetized dogs breathing through tracheostomy. A marked cardiopulmonary reflex was observed by CAPS and DW into the nasal cavity, while a prolongation of expiration was induced by LM. All these reflexes were significantly decreased by bilateral section of the posterior nasal nerve (PNN) and completely abolished by topical nasal anesthesia with lidocaine. Responses of the whole nerve activity of the PNN to these substances corresponded to the magnitude of the reflexes. These results indicate that PNN afferents play an important role on the reflex elicitation of the noxious, water and cold stimuli from the nasal cavity.

Administration, Intranasal↗

PubMed2000

Effects of perineural capsaicin treatment on cardiopulmonary reflexes elicited by laryngeal instillations of capsaicin and distilled water in sevoflurane-anesthetized dogs.

The aim of this study was to determine the effect of perineural capsaicin (CAPS) treatment on cardiopulmonary reflexes elicited by topical laryngeal instillation of CAPS and distilled water (DW) in sevoflurane-anesthetized dogs. Cardiopulmonary reflexes elicited by CAPS (10 microg/ml, 10 ml) were attenuated by perineural CAPS treatment to the superior laryngeal nerves (SLNs) (P<0.05), whereas those by DW (10 ml) remained unaffected (P>0.05). The reflex responses to DW that remained even after the perineural CAPS treatment were eliminated by laryngeal anesthesia with lidocaine. These results suggest that cardiopulmonary reflexes from the laryngeal mucosa elicited by CAPS instillation can be blocked by perineural CAPS treatment to the SLNs, which may result from inhibition of the laryngeal CAPS-sensitive C-fiber afferents.

Anesthesia↗

PubMed1989

Comparison of ultrasonically nebulized distilled water and cold-air hyperventilation challenges in asthmatic patients.

Cold-air hyperventilation (CAHC) and ultrasonically nebulized distilled water (UNDW) challenges were compared in 11 asthmatic patients who were moderately sensitive to methacholine. The challenges were performed on two separate days within one week of each other. Baseline FEV1 on each test day was greater than 70 percent of predicted. Ten of 11 subjects' FEV1 decreased at least 15 percent, and nine of 11 decreased at least 20 percent during the UNDW. Ten of 11 subjects' FEV1 decreased at least 10 percent, and eight of 11 decreased at least 15 percent during the CAHC. Using a Spearman rank coefficient, the results of the CAHC and UNDW were compared; the best correlation between the various CAHC and UNDW measurements equaled only 0.51. The correlation between UNDW and CAHC suggests that the mechanism of action of each challenge may be different.

Adult↗

PubMedDate not supplied

GC profiles of volatile constituents from human urine obtained by closed loop stripping, purge and trap technique and simultaneous stem distillation-extraction.

Different techniques like "closed loop stripping" [CLSA], "purge and trap" [PTI], and continuous steam distillation extraction [SDE] were used to establish GC profiles of major histocompatibility complex-associated volatile constituents of human urine and statistically evaluated for reliability. Of the three methods investigated, PTI appeared to be superior for the detection of very volatile substances, whereas SDE was the most efficient one with respect to yield. A number of short to medium-chain ketones, 4-hydroxy-3-methoxy-styrene, menthol and nicotine were identified in preliminary analyses.

Chromatography, Gas↗

PubMed2004

Comparison of volatile and semivolatile compounds from commercial cigarette by supercritical fluid extraction and simultaneous distillation extraction.

Supercritical carbon dioxide fluid extraction (SFE) was studied as a rapid method for extraction of volatile and semivolatile compounds of Chinese commercial cigarettes. The method was compared with simultaneous distillation and extraction (SDE). Temperature and pressure for the SFE were optimized. The extracts obtained by the two methods showed different characters in composition and represented differently the flavor characteristics of tobacco; compared to SDE, SFE can extract compounds within a shorter time and avoid the thermal degradation and solvent contamination of samples. The extracts by the two extraction methods are complementary for investigating the flavor characteristic of tobacco products.

Chromatography, Supercritical Fluid↗

PubMed1993

Physical, chemical, and nutritional characteristics of distillers dried grains with solubles for chicks and pigs.

The physical characteristics, chemical composition, and nutritional value of distillers dried grains with solubles (DDGS) from seven beverage alcohol and two fuel alcohol manufacturers were evaluated in studies with chicks and pigs. Color scores of the DDGS ranged from very light to very dark and odor scores ranged from normal to burnt or smoky. The DDGS ranged from 23.4 to 28.7% CP, 2.9 to 12.8% fat, 8.8 to 36.9% ADIN, 28.8 to 40.3% NDF, 10.3 to 18.1% ADF, and 3.4 to 7.3% ash. Lysine concentrations of the DDGS ranged from .43 to .89%. In the first experiment, 12 corn-based diets were fed to 1-d-old chicks for 21 d to assess the nutritional value of the DDGS sources. A low-protein basal diet was supplemented with soybean meal to provide 13.6, 16.5, or 19.0% CP or supplemented with 20% DDGS, which supplied approximately the same amount of CP as the highest level of soybean meal. Weight gain, feed intake, and feed/gain were influenced (P < .01) by source of DDGS. The weight gain of chicks fed the DDGS sources ranged from 85% of that chicks fed the highest level of soybean meal to less than that of chicks fed the low-protein basal diet. Blends of the three best sources of DDGS and the three poorest sources of DDGS were evaluated in a subsequent chick trial. The relative nutritional values of the two blends were similar to the average of the sources that made up the blends. Performance responses to various blends of DDGS in the pig experiment paralleled those of the chick trial.(ABSTRACT TRUNCATED AT 250 WORDS)

Animal Feed↗