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Results for “Distillation”

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At least 343 records · Page 19Linked to original sources

PubMed1984

Distilled water-induced contractions in dehydrated and skinned muscle fibers.

Dehydrated frog skeletal muscle fibers, prepared by simply immersing the muscle fibers in pure glycerol for 2-3 min, showed a marked sustained tension development in response to distilled water (DW). Similar DW-induced tension responses were also seen in mechanically skinned muscle fibers. The DW-induced mechanical responses were rapidly relaxed by a conventional relaxing solution. The marked reproducibility of the DW-induced responses, together with the simplicity of the dehydration procedure, indicates that the dehydrated fibers can be used as a substitute for the skinned fibers in studying the mechanism of contraction.

Animals↗

PubMed1989

Comparison of isotonic saline, distilled water and boiled water in irrigation of open fractures.

A prospective randomised study was carried out on 86 patients with first, second and third degree open fractures in order to compare the effect of isotonic saline, distilled water and boiled water as irrigating fluids. The standard management consisted of emergency surgical toilet, use of broad spectrum antibiotics and fracture immobilization. The results show that the outcome was not affected by the type of irrigating fluid used.

Amputation, Surgical↗

PubMed1975

Cleanup of extracts using sweep co-distillation adapted to gas chromatograph.

An adaptation of the Varian Aerograph gas chromatograph to the sweep co-distillation cleanup using the modified Storherr tube is described. The recoveries of this cleanup technique were evaluated for the mixture of four organophosphoru pesticides added to extracts from ten crop and milk. Pesticides were analyzed by gas chromatography with a cesium thermionic detector.

Animals↗

PubMed1986

The occurrence of paranuclear vacuoles in sheep ruminal epithelium treated with distilled water in vitro and from sheep injected with a large quantity of water into the rumen.

In the histological preparation taken after animal death, paranuclear vacuoles (PV) in sheep ruminal epithelium were already present in high percentage (7.5-20.3%). With the incubation of the ruminal mucosae in distilled water (10-15 degrees C) up to 120 min, PV occurrence did not alter. With incubation in NaCl solution, however, PV value decreased with time proportional to NaCl concentration (0.5, 0.85 or 1.5%). In the preparation taken by biopsy, on the other hand, PV were rare in ruminal epithelium (less than 0.3%). With the injection of warm water (10-141/animal), however, PV occurrence in the ruminal epithelium was not affected. PV as cytoplasmic processes of the ruminal Langerhans cells are probably formed by the reaction of these cells to environmental changes in the tissue caused by animal death.

Animals↗

PubMed1975

Brassica compestris var. Span: I. Fractionation of rapeseed oil by molecular distillation and adsorption chromatography.

Procedures for the large scale isolation of pure triglycerides and fractions rich in nontriglyceride components from Span rapeseed oil are described. Fractionation of Brassica campestris var. Span rapeseed oil by molecular distillation yielded 4 triglyceride fractions, all of which contained traces of sterol esters. An additional triglyceride fraction rich in free and esterified sterols and other volatile components was obtained from the oil. Separation by adsorption chromatography of Span rapeseed oil yielded three fractions; A) a pure triglyceride ffaction; B) a triglyceride fraction rich in sterol esters; and C) another fraction containing free sterols and other polar components.

Chromatography↗

PubMed1978

Nutritional and metabolic studies of distillable fractions from fresh and thermally oxidized corn oil and olive oil.

A semisynthetic diet containing 15% by weight of dietary fat was fed to six groups of male wistar rats for 28 days. Two groups received the distillable fraction of fresh corn oil (DCO) or fresh olive oil (DOO), two groups the distallable fractions of the thermally oxidized fats (OCO,OOO), and two groups received the respective fresh fats as controls (FCO, FOO). Substantial changes in the fatty acid composition occurred in the fats upon thermal oxidation. Only the rats that received OOO showed overt symptoms of heated fat toxicity. This was reflected in the histological scores of these animals with the liver sustaining the most numerous and severe lesions. Tissue fatty acid changes of any significance were confined largely to the polar liver lipid of the rats that were fed OCO or OOO. The results of this study would suggest that the relatively greater toxicity of OOO, compared to OCO, may in part be due to the high oleic:linoleic acid ratio of the fresh olive oil and in part to a higher tocopherol content of the corn oil.

Adipose Tissue↗

PubMed2003

Microwave-assisted steam distillation with simultaneous liquid/liquid extraction of pentachlorophenol from organic wastes and soils.

An efficient method for extracting pentachlorophenol (PCP) from organic solid matrices and soils using direct excitation of the fresh samples by microwave energy is presented. Steam-volatile PCP partitioned into the organic solvent n-hexane within the closed extraction vessel, resulting in recovery rates of 85-92% from aged samples. Condensed water provided a boundary layer between extract and sample thus preventing any contact of PCP with and re-partitioning into the sample. Duration of the microwave-assisted process was 35 min. Crude extracts were derivatized by heptafluorobutyric anhydride (HFBA) to improve selectivity and sensitivity resulting in detection limits of 1-2 micro g kg(-1). GC-MS/MS analyses proved that suitable extracts with only minor impurities were obtained. Common sample treatment steps like drying, thorough grinding, frequent transferring, and tedious clean-up, and concentration procedures which all can cause certain losses of analyte were minimized. The efficiency of the method was verified by comparison with an established ultrasonic extraction procedure. This microwave-assisted pressurized steam distillation with simultaneous partition into an organic phase thus provides a streamlined and efficient strategy which requires no additional investment in standard equipment for microwave-assisted extractions (MAE). Degradation of analytes at longer extraction times must be taken into account.

Chemical Fractionation↗

PubMed2002

Inhaled ultrasonically nebulized distilled water decreases exhaled nitric oxide in asthma.

Exhaled nitric oxide (eNO) is increasingly used as a marker of disease activity in asthma. Inhaled hypertonic saline has been shown to induce bronchoconstriction and to decrease eNO in asthmatic subjects, whereas the effects of hypotonic solutions on eNO in these patients have not been studied. To evaluate the effect of ultrasonically nebulized distilled water (UNDW), an indirect hypotonic stimulus, on eNO, 17 asthmatic patients were enrolled and eNO from lower airways was measured by chemiluminescence. UNDW significantly reduced FEV(1) >or= 20% in 9 subjects (UNDW+), but had no effect in eight patients (UNDW-). Baseline eNO concentration were found to be 51.3 +/- 11.1 ppb in UNDW+ and 32.9 +/- 7.5 ppb in UNDW- patients, respectively ( p = 0.199, NS). UNDW inhalation significantly decreased eNO (from 51.3 +/- 11.1 ppb to 31.0 +/- 7.1 ppb in UNDW+ ( p < 0.020, n = 9) and from 32.9 +/- 7.5 ppb to 26.2 +/- 7.3 ppb in UNDW- subjects ( p < 0.024, n = 8), respectively). eNO percentage reduction in UNDW+ patients was significantly higher compared with UNDW- subjects (-37 +/- 4% vs -23 +/- 3%, p = 0.021). There was no correlation between FEV(1) changes and eNO percentage decreases in both UNDW+ and UNDW- subjects. In UNDW+ patients, acute bronchodilation induced by salbutamol caused a recovery in both FEV(1) and eNO, though eNO levels remained lower than baseline values. We concluded that UNDW inhalation can significantly decrease eNO in asthmatic patients, either responders or nonresponders to this indirect osmotic challenge; the reduction in eNO levels was only partly dependent on acute changes in airway caliber.

Administration, Inhalation↗

PubMed2006

Biocatalytic acylation of carbohydrates with fatty acids from palm fatty acid distillates.

Palm fatty acid distillates (PFAD) are by-products of the palm oil refining process. Their use as the source of fatty acids, mainly palmitate, for the biocatalytic synthesis of carbohydrate fatty acid esters was investigated. Esters could be prepared in high yields from unmodified acyl donors and non-activated free fatty acids obtained from PFAD with an immobilized Candida antarctica lipase preparation. Acetone was found as a compatible non-toxic solvent, which gave the highest conversion yields in a heterogeneous reaction system without the complete solubilization of the sugars. Glucose, fructose, and other acyl acceptors could be employed for an ester synthesis with PFAD. The synthesis of glucose palmitate was optimized with regard to the water activity of the reaction mixture, the reaction temperature, and the enzyme concentration. The ester was obtained with 76% yield from glucose and PFAD after reaction for 74 h with 150 U ml(-1) immobilized lipase at 40 degrees C in acetone.

Acylation↗

PubMed2006

Effect of different fermentation conditions on the kinetic parameters and production of volatile compounds during the elaboration of a prickly pear distilled beverage.

An experimental design considering thermal treatment of must, yeast strain, prickly pear variety and degree of ripeness was chosen to evaluate the fermentation behavior and generation of volatile compounds, during the elaboration of a distilled beverage from prickly pear. Four Mexican prickly pear varieties were characterized physically and two of them were selected for fermentation studies. The thermal treatment of the must showed the highest statistical influence on fermentation behavior and production of volatile compounds, followed by prickly pear variety, then yeast strain and finally the degree of ripeness was the least statistically significant factor. The growth rate increased when the thermal treatment was applied whereas the ethanol production rate and alcoholic efficiency were unaffected. The results also suggested that thermal treatment was effective for inhibition of microbial contamination. As regards volatile compounds production, acetic acid and methanol decreased while other volatiles increased when the thermal treatment was applied. Despite the influence of thermal treatment, prickly pear variety strongly influences the volatile profile of fermented musts.

Acetaldehyde↗

PubMed2005

Identifying and selecting the common elements of evidence based interventions: a distillation and matching model.

A model is proposed whereby the intervention literature can be empirically factored or distilled to derive profiles from evidence-based approaches. The profiles can then be matched to individual clients based on consideration of their target problems, as well as demographic and contextual factors. Application of the model is illustrated by an analysis of the youth treatment literature. Benefits of the model include its potential to facilitate improved understanding of similarities and differences among treatments, to guide treatment selection and matching to clients, to address gaps in the literature, and to point to possibilities for new interventions based on the current research base.

Evidence-Based Medicine↗

PubMed1990

DNA fluorometric assay in 96-well tissue culture plates using Hoechst 33258 after cell lysis by freezing in distilled water.

A simple assay is described using bisbenzimidazole (Hoechst 33258) to determine cellular DNA content in 96-well tissue cultures plates. At time points of interest, the plates are emptied of media and stored frozen. When the assay is to be performed, cultures are briefly incubated in distilled water and frozen again. This process lyses the cells and allows rapid and thorough mixing of the fluorochrome and cellular DNA. Freezing permits convenient storage of cultures until the time of assay. Experiments can be batched, further reducing processing time and giving better intra- and interexperimental standardization. The assay generates a linear standard curve for DNA fluorescence versus cell number, the range of which is appropriate for microculture wells. This enables the rapid and accurate measurement of cell number involving minimal processing time, making this assay well suited for cell proliferation studies.

Bisbenzimidazole↗

PubMed1981

Volatile fatty acids in human peripheral and portal blood: quantitative determination vacuum distillation and gas chromatography.

In order to determine volatile fatty acids (VFA) in human blood, gas chromatographic analyses were performed after blood samples had been pre-treated by a vacuum distillation procedure with subsequent evaporation. Results of the reproducibility study, investigated by pre-treating five aliquots of one human serum sample showed C.V. values ranging from 7.4 to 18.2. Normal serum VFA values were determined in individual serum samples collected from healthy subjects and compared to those present in serum from patients undergoing gall-bladder surgery. The serum VFA values were comparable in the two groups. In the surgical patients, blood was also collected from the portal circulation. All portal serum VFA values, except that of iso-butyric acid, were higher than those found in the samples collected from the peripheral arm vein. VFA values were also determined in serum specimens obtained from blood collected from the arm vein of patients with extensive cirrhosis of the liver. The VFA values showed marked individual variations and were higher than those found in peripheral samples from healthy subjects and patients undergoing gall-bladder surgery, but were lower than those found in samples from the portal circulation from the surgical patients.

Arm↗

PubMed1991

The role of chronic acanthosis and subacute inflammation in tumor promotion in CD-1 mice by petroleum middle distillates.

An initiation-promotion bioassay using CD-1 mice was conducted to examine the role of chronic acanthosis and inflammation in tumor promotion by petroleum middle distillates (MD). Test groups were initiated with 7,12-dimethylbenz[a]anthracene (DMBA). Promotion with MD consisted of twice weekly treatments for 25 weeks with either 25 or 50 microliters, 50 microliters + daily treatment with 15 micrograms dexamethasone, 50 microliters + postapplication washings, or 100 microliters. Three mice from each group were euthanized at 21-day intervals (24 total per group). The skin from interim euthanized mice was examined histopathologically for tumors, acanthosis, and subacute inflammation. Tumor incidence at study termination was as follows: 25 microliters (45%), 50 microliters (43%), 50 microliters + dexamethasone (0%), 50 microliters + washing (70%), and 100 microliters (81%). A correlation of greater than 0.93 was observed at all intervals between tumor incidence and cumulative group mean degrees of acanthosis in interim euthanized mice. The correlation between subacute inflammation at early through midstudy interval weeks and tumor incidence at study termination was poor. These results support the hypothesis that induction of a lasting, albeit mild, hyperplasia is an essential, but not sufficient requirement for tumor promotion. Furthermore, subacute inflammation does not appear to be a significant factor in tumor promotion by petroleum MD.

9,10-Dimethyl-1,2-benzanthracene↗

PubMed1986

Late bronchial response and increase in methacholine hyperresponsiveness after exercise and distilled water challenge in atopic subjects with asthma with dual asthmatic response to allergen inhalation.

We investigated the occurrence of late asthmatic response and increased methacholine responsiveness after exercise and ultrasonically nebulized distilled water (UNDW) inhalation in 12 subjects with asthma with dual asthmatic response and increased responsiveness after allergen challenge. On 3 separate days, allergen, exercise, and UNDW challenges were performed 2 hours after methacholine. FEV1 was measured for 8 hours to detect any delayed change in airway caliber. If there were a further significant reduction in FEV1 after the recovery from the immediate bronchoconstriction, methacholine challenge was performed again when FEV1 had returned to baseline. Reproducibility of any observed late response to exercise and UNDW was also investigated by repeating these challenges on 2 subsequent days. After allergen inhalation only nine subjects had an early asthmatic response, whereas all the tested subjects demonstrated a late reaction and increased methacholine responsiveness. Ten subjects had an immediate response to exercise, and this was followed by a late response in only four patients. Nine subjects demonstrated early response to UNDW inhalation, and five subjects also had a late reaction. These late responses were associated with an increase in methacholine responsiveness in a subset of the tested subjects. Late-phase reactions to exercise and UNDW were not reproducible.

Administration, Inhalation↗

PubMed1986

Acute toxicity of petroleum- and shale-derived distillate fuel, marine: light microscopic, hematologic, and serum chemistry studies.

Rats were gavaged with 60, 48, 38, 30, or 24 ml/kg of either petroleum (P) or shale (S)-derived distillate fuel, marine (DFM). Surviving rats were killed 14 days after dosing. There was a slight difference in toxicity of the two fuels but neither fuel was very toxic. The LD50/14 was 43 ml/kg for P-DFM and 50 ml/kg for S-DFM. Lesions in rats that died indicated hepatic and renal toxicity. In another study, rats were gavaged with 24 ml/kg of either P- or S-DFM and killed at 1, 2, or 3 days after dosing. Prominent clinicopathologic findings included loss of body weight, hematologic evidence of dehydration, transient leukopenia, and serum chemistry and histopathologic alterations indicative of mild hepatic and renal toxicity.

Animals↗

PubMed1985

Quantification of tumour initiating effect of jute batching oil and its distillates over mouse skin.

In order to identify the tumour initiating constituent(s) of a mineral oil, jute batching oil (JBO), used in the processing of jute fibres, it was fractionally distilled in various boiling range fractions. The latter were then subjected to in vivo assessment of their aryl hydrocarbon hydroxylase (AHH) inducing potential in mouse epidermis. Fractions with almost similar AHH inducing potential were regrouped and studied for their tumour initiating potential over mouse skin following two-stage initiation-promotion protocol and using 12-O-tetradecanoyl phorbol-13-acetate (TPA) as tumour promoter. It was noticed that: (1) JBO as initiator, provoked local development of benign skin tumours over mouse back; (2) fractions of JBO boiling below 335 degrees C and above 399 degrees C accounted for most of the tumour initiating potential of the oil; (3) the histological features of the tumours (i.e. benign papillomas and keratoacanthomas) initiated by these fractions were similar to those developed after being initiated with unfractionated or reconstituted JBO; (4) removal of these fractions from JBO may be attempted which could decontaminate the batch oil from most of its tumorigenic components and make it safer for industrial use.

Animals↗

PubMed2004

New aspects on the preparation of [11C]acetate--a simple and fast approach via distillation.

[11C]Acetate, initially developed for nuclear cardiology has gained increased interest also for oncological problems. A conjoint problem of all preparation methods is the high sensitivity of the Grignard-precursor to moisture, demanding long cleaning and drying procedures of apparatus and reaction vials. Our rationale was to simplify and accelerate the preparation of [11C]acetate by the development of an inert, sterile and disposable system. The present publication deals with the remote-controlled preparation of [11C]acetate via distillation into a buffer ready to use.

Acetates↗