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PubMedDate not supplied

Modified gas chromatographic/mass spectrometric method for determination of daminozide in high protein food products.

A modified version of the Conditt and Baumgardner gas chromatographic/mass spectroscopic (GC/MS) method for determination of daminozide in peanut butter and raw peanuts is described. Daminozide in the food product is hydrolyzed to unsymmetrical dimethylhydrazine (UDMH) by sodium hydroxide digestion. The generated UDMH is distilled from the food matrix and captured by reaction with salicylaldehyde in a condensation trap. Resulting high pH distillates generated by peanuts and peanut products are adjusted back to a pH of 5-6 through addition of glacial acetic acid. After thermal incubation and extraction into methylene chloride, salicylaldehyde dimethylhydrazone is separated from interferences by capillary GC and quantitated by MS using the selective ion monitoring (SIM) mode. Quantitation of daminozide is based on the ratio of the salicylaldehyde dimethylhydrazone molecular ion (m/z 164) to the molecular ion (m/z 153) of the internal standard, 4-nitroanisole. Confirmation of daminozide identity is determined by relative intensity of the m/z 164 ion to the m/z 120 (C7H4ON) ion. Improved m/z 164 ion intensity and reduction of neighboring interferences due to acetic acid treatment permitted a daminozide detection limit of 0.005 ppm in a 50 g sample and an associated 0.02 ppm limit of quantitation. This modification is specific for high protein samples that generate high pH distillates such as peanuts and peanut products and is not specifically intended for analysis of low protein samples.

Arachis↗

PubMed1990

[Evaluation of the changes in intracranial water, sodium, phosphorus metabolites and intracellular cerebral pH in rats with acute dilutional hyponatremia].

Although most prominent among the clinical manifestations associated with hyponatremia are central nervous system (CNS) symptoms, the alterations in brain function remain poorly understood. In the present study, the alterations in intracellular cerebral pH and intracranial water, sodium and phosphorus metabolites content in rats with acute dilutional hyponatremia were examined by using an in vivo nuclear magnetic resonance (NMR) technique which noninvasively provides continuous informations on intracellular phenomena. Acute dilutional hyponatremia was induced on anesthetized male Sprague-Dawley rats by intraperitoneal injection of distilled water with an initial dose of 10 ml/100 g bw, followed by an additional dose of 5 ml/100 g bw 40 min later. Arterial blood sampling and NMR measurements were made before and every 60 min after the initial injection of distilled water. The treatment with distilled water resulted in dramatic falls in serum Na, Cl and osmolality at 60 min after water loading (Na; from 143.4 +/- 2.6 to 112.3 +/- 1.3 mmol/l, Cl; from 101.02 +/- 2.2 to 78.4 +/- 5.4 mmol/l, Osm; from 306.3 +/- 5.8 to 247.3 +/- 7.3 mOsm/kg H20). 1H-NMR imaging showed the accumulation of brain water as dilutional hyponatremia developed. Intracranial Na content measured by 23Na-NMR spectroscopy decreased significantly at 60 min after of water loading to about 70% of that observed under control condition. Since it has been demonstrated that solute extrusion from the brain with resultant reduction of brain swelling occurs within 60 min after the dilution, this result may be, at least in part, explained by this protective mechanism.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Disease↗

PubMed1990

[A study on disintegration of posterior composite resins caused by long-term water immersion].

The purpose of this study is to clarify a cause of disintegration for posterior composite resins by long-term immersion in distilled water during the 3-year period. Three kinds of posterior composite resins [Bellfirm P (BP), Clearfil Posterior (CP) and Micro Jar (MJ)] and one conventional anterior composite resin [Clearfil FII (FII)] were prepared as to specimens with 20 mm diameter, and 1 mm in thickness. These specimens were immersed in distilled water at 37 +/- 1 degree C for 3 years. These specimens were observed by scanning electron microscope (SEM). The residuces in distilled water were analyzed by X-ray microdiffractometry, infrared (IR) and nuclear magnetic resonance (NMR) spectrometers. One posterior composite resin (microparticle filled resin) was eluted in water more than the other posterior and anterior composite resins with conventional fillers. In SEM observations, many air bubbles were found inside all sections of the four composite resins, because of all mixing type composite resins. The subsurface layer of all four composite resins showed signs of disintegration, but the center layer of the specimens was not disintegrated. Three cured composite resins except MJ had crystalline X-ray diffraction patterns before water immersion, but the cured MJ alone was amorphous. These peaks of crystals showed fillers of these composite resins respectively. X-ray diffraction patterns of the dissolved substances for three composite resins except BP were also crystalline, but the peaks of the crystals except CP were different from the peaks of the fillers respectively. In IR and 1H-NMR spectra of dissolved substances, an unreacted monomer could be detected in one posterior composite resin (BP), but not in the other composite resins. In 1H-NMR spectra of dissolved substances, new signals not found originally were observed in all four composite resins. Therefore, the progress of disintegration was demonstrated clearly. The dissolved substances of all four composite resins were shown as the disintegrated substances between resin matrixes and silane coupling agents. It is suggested that the disintegration of these composite resins by long-term water immersion is derived from hydrolysis.

Composite Resins↗

PubMed1990

Lack of effect of fluoride on reproductive performance and development in Shetland sheepdogs.

A 10-y history of high rates of perinatal deaths and congenital anomalies in dogs in a Shetland Sheepdog kennel prompted investigations into the cause(s). Skeletal fluorosis (mottled teeth in pups, bony exostoses in adults) followed use of a commercial dog food later found to contain 460 ppm fluoride (F) from rock phosphate added as a mineral source. The effects of the water source and fluoride in dog food on female reproduction and teratogenicity were investigated in a 2-y, 2-way factorial study in the kennel. Twenty adult shelties of proven fertility were brought into the kennel and randomized into 4 treatment groups, each consisting of 4 females and 1 male. Treatments were: Group A, high F (460 ppm) dog food, well water; Group B, high F dog food, distilled water; Group C, low F (55ppm) dog food, well water; Group D, low F dog food, distilled water. Only Group C produced as many pups as expected. Overall the missed pregnancy rate (44%) in study bitches and perinatal death rate (50%) in 48 study pups paralleled the problems in shelties resident in the kennel. Higher rates for both variables in the high F and the distilled water groups seemed likely due to chance. The only major anomaly was in Group D; minor anomalies appeared in all groups. Although 460 ppm F in dog food did produce bony exostoses, we did not find convincing evidence that it adversely affected reproduction in shelties. The cause of the reproductive problems was apparently not the dog food, water, foliage, genetic factors, or infectious disease and currently remains undetermined.

Abnormalities, Drug-Induced↗

PubMed1989

[Preparation of a protein mucin solution to be used in patients with xerostomia (Venezuela)].

The purpose of this study was to prepare a protein solution to simulate natural saliva using mucin extracted from bovine submaxillary gland. The extraction process was done in keeping with Drans & Leung's (1980) modified technique. Once the bovine submaxillary gland was extracted (approximately 500 g), it is cut and stored in distilled water for 12 hrs at 4 degrees C in order to eliminate any tissue or blood remaining in the section. The tissue is then homogenized and suspended in a phosphate buffer solution with a pH of 7 for 48 hours. The solution is then centrifuged and the supernatant is treated to extract the protein present in the solution. The remaining solution is dialyzed with distilled water, changed three times and then lyophilized. The lyophilized product is diluted in distilled water (1 g/1) taking aliquots to determine the pureness of the proteins. The solution obtained has a viscosity and protein composition which is very similar and offers great advantages for use in patients who suffer from severe xerostomy.

Adolescent↗

PubMed1989

Recovery of warfarin from an enteral nutrient formula.

The in vitro recovery of warfarin from an enteral nutrient formula after filtration to remove the protein-bound fractions was determined. This study was conducted in two parts. In part 1, 0.25-, 0.50-, and 1-mL aliquots of warfarin sodium stock solution were added to 150 mL of the enteral nutrient formula Osmolite under physiologic conditions to produce warfarin concentrations of 16.7, 33.3, and 66.7 micrograms/mL. In part 2, a 0.5-mL aliquot of the warfarin sodium stock solution was added to Osmolite 100 mL-distilled water 50 mL, Osmolite 75 mL-distilled water 75 mL, and Osmolite 150 mL. The samples were filtered through a membrane that retained macromolecules while allowing warfarin to pass through, and the warfarin concentration was measured by high-performance liquid chromatography. Assays of protein-free buffered control solutions of warfarin before and after filtration indicated that no significant amount of warfarin was retained in the filtration membrane. Significantly less warfarin was recovered from full-strength Osmolite after filtering than before filtering at all warfarin concentrations tested. Significantly more warfarin was recovered from the Osmolite-distilled water solutions than from the undiluted Osmolite. These results suggest that there is some sequestering of warfarin in the macromolecular fraction of the enteral nutrient formula. The decreased recovery of warfarin from the enteral nutrient formula used in this study has potential clinical importance, but further research in humans is needed to substantiate these in vitro observations.

Chromatography, High Pressure Liquid↗

PubMed1989

[The quantitative determination of cyanide by FTD-GC].

In recent buildings, new materials containing chemical goods, chemical fibers and the like are in common use. Some of them evolve hydrogen cyanide (HCN) when burning. When a person meets a fire, therefore, it is necessary to measure his blood concentration of HCN as well as that of CO-Hb%. The blood concentration of HCN can be measured by colorimetry such as pyridine-pyrazolone method, gas-chromatography, electrode method, or the like. However, these methods require much time in pretreatment and the preparation of the reagent. We have investigated to find a new measurement method free from the above demerits, so that we have found the method by FTD-GC (Flame Thermionic Detecter Gas-chromatograph) is convenient and can be effected in a short time in comparison with the aforementioned method. GC-7AG made by Shimadzu Co. is employed as gas-chromatography and the headspace method is used in the quantitative determination. Samples are employed as solutions of potassium cyanide (KCN) either in distilled water or in fresh blood. The concentration of KCN is gradient in the range of 0.5-6 micrograms/ml. The quantitative conditions is investigated by a solution in distilled water as standard. Using this method, the concentration of HCN in the blood sample is determined slightly lower than that in the distilled water; however, this method is advantageous in convenience and the saving of time. Therefore, the method is useful in practice for the determination of the concentration of HCN.(ABSTRACT TRUNCATED AT 250 WORDS)

Chromatography, Gas↗

PubMed1989

[Disintegration of visible light-cured composite resins caused by long-term water immersion].

The purpose of this study is to clarify a cause of disintegration of composite resins by long-term immersion in distilled water. Three kinds of visible light-cured composite resins (Heliosit, Plurafil Super and Visio Dispers) and one conventional composite resin (Clearfil F II) were prepared as the specimens with a 20 mm diameter and 1 mm thickness. These specimens were immersed in distilled water at 37 +/- 1 degree C for 3 years. These specimens were analysed and observed by a comprehensive multi analyzer and scanning electron microscope. The other hand residues in distilled water were analysed by infrared (IR) and nuclear magnetic resonance (NMR) spectrometers. The surface layer of all four composite resins showed signs of disintegration. The composite resins with abundant dissolved substances had disintegrated markedly, and such disintegration occurred deep inside the specimens. In IR and 1H-NMR spectra of dissolved substances, two visible light-cured composite resins (Heliosit and Plurafil Super) could be detected unreacted monomers, but one visible light-cured composite resin (Visio Dispers) and one conventional composite resin (Clearfil F II) could not be detected them. In 1H-NMR spectra of dissolved substances of all four composite resins, new signals not composed originally were observed. The progress of disintegration were demonstrated clearly. The dissolved substances were shown as the disintegrated substance between resin matrixs and silane coupling agents. It is suggested that the disintegration of composite resins by long-term water immersion is derived from hydrolysis.

Composite Resins↗

PubMed1989

Effect of calcium lactate in erosion and S. mutans in rats when added to Coca-Cola.

Thirty-six Sprague Dawley rats, 22 days of age, were divided randomly into three groups of 12 each and housed in a programmable feeder. The three experimental groups received either Coca-Cola (CC), Coca-Cola with calcium lactate (CC-CaL), or distilled water. The programmable feeder was set to deliver 17 equal volumes of fluid per day with each feeding period lasting between 80-90 min. All groups were given Diet MIT 305 in one premeasured amount per 24 hr period (ad libitum). The pH of the CC with calcium lactate was adjusted to match the CC without calcium lactate by the addition of citric and phosphoric acids. The test period lasted five weeks. Each week, the food and fluid consumed and the weight gain were measured. Erosion of the teeth was scored by the method of Restarski et al. (1945). ANOVA indicated that there was a significant difference in the amount of erosion among groups. A Newman-Keuls analysis showed that the mean erosion score of the CC group was significantly greater (P less than 0.05) than that of the CC-CaL and distilled water groups (54.2 +/- 0.12; 0.0275 +/- 0.0123; 0.132 +/- 0.070, respectively). There was no significant difference in erosion between the CC-CaL and distilled water groups. There was no difference in the amount of food and fluid consumed among the group of rats. In conclusion, calcium lactate added to CC resulted in significantly reduced tooth erosion in rats.

Analysis of Variance↗

PubMed1989

[Fluoride contents in tea and Sakura-shrimp in relation to other inorganic constituents].

The purpose of this study is to determine the fluoride contents of shrimp and of tea samples obtained from Shizuoka prefecture which is famous for tea products area and fishery market and to examine the relations between fluoride and other mineral contents, such as calcium, magunesium and phosphorus. Fluoride contents in tea produced in this area have been reported by Matsuura and Kokubu and other investigators, but more recent data are scarce. Samples were taken from a kind of shrimp known as Sakura-shrimp and from 4 kinds of commercial tea (coarse tea, 2 kinds of green tea and refined green tea). After having been dried and powdered, 1g of each sample was reduced to ashes at 550 degrees C for 10 hours with Ca(OH)2 as a fluoride fixative. Fluoride was distilled from each ash sample at about 140 degrees C with HClO4, and about 200 ml of distillate was collected from each sample. Fluoride contents were determined by means of ion-specific electrode. Calcium and magnesium contents were determined by atomic absorption spectrophotometry, and phosphorus contents were determined by Chen, Toribara and Warner's method. Total fluoride contents of the samples were as follows: 61.73ppm in shrimp, 180.16ppm in coarse tea, 72.62ppm and 89.02ppm in the 2 kinds of green tea, and 71.11ppm in refined green tea. More than 99% of the total fluoride was obtained from 150ml distillate of each sample. Calcium contents were extremely high in shrimp (21,822ppm) and 2,106-2,693ppm in tea samples. Magnesium contents were highest in shrimp (3,088ppm) and lowest in coarse tea (1,333ppm).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMedDate not supplied

Comparison of the ion exclusion chromatographic method with the Monier-Williams method for determination of total sulfite in foods.

Experimental data comparing the alkali extraction/ion exclusion chromatographic method with the Monier-Williams method for determination of total sulfite are presented in (a) enzymatic and nonenzymatic browning systems, (b) vegetables containing naturally occurring sulfite, and (c) a carbohydrate-type food additive, erythorbic acid. Excellent agreement, with a linear correlation coefficient of 0.99, was observed in fresh potato samples homogenized with sulfite and allowed to react for different time intervals (enzymatic browning system). A good overall correlation was observed in dehydrated, sulfited apple samples heated for different times (nonenzymatic browning system); however, as heating time increased, higher results were obtained by the Monier-Williams method than by the alkali extraction/ion exclusion chromatographic method. The results of determining sulfite in the alkali trapping solution following acid distillation or acid treatment without heat suggested that this deviation was due to a fraction of sulfite bound to the browning reaction products in such a way that it was released by acid distillation but not by alkali extraction or acid treatment without heat. Similar behavior was demonstrated in cabbage with naturally occurring sulfite, which was released by acid distillation but not by alkali extraction or acid treatment without heat. The ion exclusion chromatographic method could overcome interference by the volatile caramelization reaction products in the Monier-Williams determination of erythorbic acid.

Brassica↗

PubMed1988

[Iatrogenic tumor cell implantation in bladder cancer].

J82 monolayer cell cultures and 647 V multicellular tumor spheroids were incubated in Resectal, urine (pH 5.5; 7.5) and distilled water for 5-30 min. In the case of both monolayers and tumor spheroids inhibition of tumor cell growth was achieved by incubation in distilled water. Transurethral resection (TUR) of a primary superficial bladder cancer was performed in 133 patients (Ta, T1). In 60 of these patients selected biopsies of apparently normal bladder mucosa were taken at the same time. There was no significant difference in tumor recurrence between the groups with biopsy and without biopsy. However, all patients with dysplasia in the selected mucosal biopsies developed a tumor recurrence. Between 1969 and 1984 bladder wall perforation occurred in 12 patients during TUR of Ta, T1 bladder cancer. None of the patients who experienced bladder wall perforation developed extraperitoneal or intraperitoneal metastases. Although our clinical results suggest that iatrogenic tumor cell implantation during TUR of a bladder cancer is rather unlikely, this event could be prevented by the use of distilled water during and after TUR.

Adult↗

PubMed1986

Effect of soya bean oil on symptoms, gastric emptying and gut hormone release in patients with postvagotomy symptoms.

In a preliminary study the effect of an aperitif of a stable fat emulsion on symptoms, gastric emptying of a hypertonic glucose meal and associated release of insulin, neurotensin, enteroglucagon, gastric inhibitory polypeptide (GIP) and vasoactive intestinal polypeptide (VIP) was evaluated in 9 patients with postprandial gastrointestinal discomfort after vagotomy. In each patient gastric emptying of the glucose meal was measured twice: 20 min after intake of distilled water and after fat emulsion. On both occasions neurotensin, enteroglucagon and GIP rose significantly from fasting values. In contrast to distilled water, the fat emulsion was able to significantly activate the release of the hormones before ingestion of the glucose meal. All the patients had a rapid emptying of the glucose meal after distilled water and they experienced symptoms that corresponded with the nature of their spontaneous symptoms after ordinary meals. The fat emulsion reduced the early emptying of the meal and relieved the symptoms of the dumping patients, whereas gastric emptying and symptoms were variable in the patients with diarrhoea and other postvagotomy symptoms. The intake of an aperitif of soya bean oil seems to be an effective treatment only in patients with the dumping syndrome.

Adult↗

PubMedDate not supplied

Improved method for determination of volatile nitrosamines in baby bottle rubber nipples and pacifiers.

A method is described for determining volatile nitrosamines in baby bottle rubber nipples and pacifiers. The method consists of overnight soaking of the sample with dichloromethane in the presence of propyl gallate, an inhibitor for artifactual formation of nitrosamines; extraction with dichloromethane using an ambient temperature column procedure; distillation from aqueous alkali; extraction of the aqueous distillate with dichloromethane and concentration of the extract using a Kuderna-Danish concentrator; and final analysis by gas chromatography with detection by thermal energy analyzer. Major improvements over other published methods include a simpler extraction, a more efficient distillation and concentration to minimize losses, and incorporation of propyl gallate inhibitor as well as of a test to detect unsuitable dichloromethane solvent that otherwise might lead to artifactual formation. The method is highly accurate (approximately 90% recovery) and precise (av. CV = 4.7% at greater than 9 ppb levels) and is applicable to determination of nitrosamines in both rubber- and plastic-based products.

Chemical Phenomena↗

PubMedDate not supplied

Determination of ethanol in wine by titrimetric and spectrophotometric dichromate methods: collaborative study.

A dichromate-spectrophotometric method for the determination of ethanol in wine was compared in a collaborative, matched pair study with the AOAC dichromate-titrimetric method, 11.008-11.011. Both methods require distillation of the sample into dichromate. The titrimetric method measures ethanol by titrating the excess dichromate with ferrous ammonium sulfate after conversion of ethanol to acetic acid; the spectrophotometric method directly measures the reduced dichromate formed after oxidation. In addition to comparing the 2 methods, the collaborative study also compared the use of 2 types of assemblies for obtaining the ethanol distillate: the Scott-type, which is used in 11.008-11.011, and the electric Kirk-type. Results of the collaborative study indicated that the repeatability and reproducibility of the official titrimetric method were generally far superior to those of the spectrophotometric method; therefore, adoption of the spectrophotometric method is not recommended. Comparison of titrimetric method results obtained using the 2 types of stills indicated that repeatability and reproducibility were somewhat better when Scott apparatus was used, but measurements using Kirk-type compared well in the range of ethanol concentrations found in table and fortified wines. The Kirk-type distillation apparatus has been adopted official first action as an alternative to Scott apparatus in the dichromate oxidation method for ethanol in wine, 11.008-11.011.

Chromates↗

PubMed1984

[Combination (RaHPP) of radiotherapy, hyperthermia and chemotherapy (peplomycin and picibanil) for bladder cancer].

Four patients with urinary bladder carcinoma were treated by combination therapy which consisted of hyperthermia vesical irrigation of two anticancer drugs (peplomycin and picibanil), intravesical instillation of those drugs and radiation. Following the therapeutic method we planned, 40 mg of peplomycin and 10 KE of picibanil in 1,500 ml of sterile distilled water was irrigated at 42 to 43 degrees C into the bladder for 3 hours; 40 mg of peplomycin and 10 KE of picibanil in 40 ml of sterile distilled water was instilled into the bladder; and, the focus was irradiated with 60Co to a focal dose of 200 rad 30 minutes later. This pattern of treatment was repeated once a week, 3 to 5 times in total. On the days this pattern was not taken, 5 KE of picibanil in 20 ml of sterile distilled water was instilled into the bladder cavity. Complete response was observed in one patient and partial response in 3 patients. The side effect was temporary irritable bladder symptom.

Aged↗

PubMed1984

Studies on the contributive effects of the different constituents of cow's urine concoction in rats (Part I).

The effects of cow's urine concoction (CUPR) and of the concoction in distilled water (CUPRw) were assessed on convulsion and the effects of each of the constituents in cow's urine or distilled water was also assessed. The basic procedure involved was observing for convulsion, the time of its occurrence and its duration, and time for recovery or death following the administration of the concoction and each of its constituents in distilled water or cow's urine. The results showed that the CUPR paradoxically induced convulsion while the CUPRw did not. Of the individual constituents (in either medium) tobacco gave appreciable results on the convulsion, thus suggesting that it is the active ingredient. In instances where convulsion was recorded, its onset and duration followed with or without death, is a function of the dose employed. The administration of cow's urine and some of the constituents alone produced no remarkable results, though when given in randomized combination some significant findings were recorded. It is suggested that the possibility of interaction between the various constituents is high and that there is a differential solubilization of the constituents in the media, thus bringing about qualitative and quantitative differences in the observations. The claim by the herbalists that the concoction is effective in eliminating convulsions is questionable as we observed that the concoction obtained from three different herbalists did not protect against strychnine-induced convulsion.

Animals↗

PubMed1984

Fractionation of skin tumor-initiating activity in coal liquids.

Narrow temperature range distillates from biologically active solvent refined coal-I and -II heavy-end coal liquids were fractionated according to chemical class and assayed for initiation of skin carcinogenesis in CD-1 mice. In addition, instrumental chemical analyses were performed on the distillates and their chemical fractions. Results showed that initiation activity in these complex fuel mixtures could be segregated both by boiling point and chemical class. Neutral polycyclic aromatic hydrocarbon fractions were the most active of the chemical classes, with some initiating activity being shown by nitrogen-containing polycyclic aromatic hydrocarbon. Aliphatic and hydroxylated polycyclic aromatic hydrocarbon fractions showed little or no initiating activity. For the two solvent refined coal-II distillates studied, initiating activity was substantially higher in the material boiling above 850 degrees F than in that boiling 800-850 degrees F, although both contained essentially the same concentrations of benzo[a]pyrene. These data indicate that the overall initiating activity of these complex mixtures is highly dependent on interactions of the many chemical carcinogens and that relative concentrations of known carcinogenic polycyclic aromatic hydrocarbons, such as benzo[a]pyrene and dimethylbenz[a]anthracene, are not the sole determinants of initiating activity.

Animals↗