Biomedical subjects

S Kage

Publications and source records attributed to S Kage.

13 recordsLinked to original sources

PubMed2001

A simple method for detection of gunshot residue particles from hands, hair, face, and clothing using scanning electron microscopy/wavelength dispersive X-ray (SEM/WDX).

We devised a simple and rapid method for detection of gunshot residue (GSR) particles, using scanning electron microscopy/wavelength dispersive X-ray (SEM/WDX) analysis. Experiments were done on samples containing GSR particles obtained from hands, hair, face, and clothing, using double-sided adhesive coated aluminum stubs (tape-lift method). SEM/WDX analyses for GSR were carried out in three steps: the first step was map analysis for barium (Ba) to search for GSR particles from lead styphnate primed ammunition, or tin (Sn) to search for GSR particles from mercury fulminate primed ammunition. The second step was determination of the location of GSR particles by X-ray imaging of Ba or Sn at a magnification of x 1000-2000 in the SEM, using data of map analysis, and the third step was identification of GSR particles, using WDX spectrometers. Analysis of samples from each primer of a stub took about 3 h. Practical applications were shown for utility of this method.

Cause of Death↗

PubMed2000

Determination of nitrate in blood by gas chromatography and gas chromatography-mass spectrometry.

We devised a sensitive and simple method for determining nitrate in whole blood, using an extractive alkylation technique. Nitrate in whole blood was reduced to nitrite by hydrazine sulfate in the presence of Cu2+ and Zn2+ as catalysts, and alkylated with pentafluorobenzyl bromide using tetradecyldimethylbenzylammonium chloride as the phase-transfer catalyst. The obtained derivative was analyzed qualitatively by gas chromatography-mass spectrometry and quantitatively by gas chromatography with electron-capture detection. The detection limit of nitrate in whole blood was 0.01 mM. The calibration curve was linear over the concentration range from 0.02 to 1.0 mM for nitrate in whole blood. The accuracy and precision of the method were evaluated and the relative standard deviations were found to be within 10%. Using this method, the blood nitrate levels of two victims who committed suicide by inhaling automobile exhaust gas were determined.

Alkylation↗

PubMed2000

Determination of azide in blood and urine by gas chromatography-mass spectrometry.

A sensitive and simple method for determining azide in blood and urine using an extractive alkylation technique was devised. This inorganic anion was alkylated with pentafluorobenzyl bromide using tetradecyldimethylbenzylammonium chloride as the phase-transfer catalyst. 1,3,5-Tribromobenzene was used as an internal standard. The obtained derivative was analyzed by gas chromatography-mass spectrometry using the negative ion chemical ionization mode with isobutane as the reagent gas. The calibration curves for azide were linear over the concentration range from 1 to 200 nmol/mL in blood and urine, and the lower limit of detection was 0.5 nmol/mL for blood and urine. The accuracy and precision of the method were evaluated, and the coefficients of variation were found to be lower than 10%.

Forensic Medicine↗

PubMed1998

A fatal case of hydrogen sulfide poisoning in a geothermal power plant.

An adult man entered an oil separator room to remove waste oil from a vacuum pump in a geothermal power plant. He suddenly collapsed and died soon after. Since hydrogen sulfide gas was detected in the atmosphere at the scene of the accident, poisoning by this gas was suspected and toxicological analysis of sulfide and thiosulfate in blood, brain, lung, femoral muscle was made using the extractive alkylation technique combined with gas chromatography/mass spectrometry (GC/MS). The concentrations of sulfide in these tissues were similar to those previously reported for fatal cases of hydrogen sulfide gas. The concentration of thiosulfate in the blood was at least 48 times higher than the level in control samples. Based on these results, the cause of death was attributed to hydrogen sulfide gas poisoning.

Accidents, Occupational↗

PubMed1997

The usefulness of thiosulfate as an indicator of hydrogen sulfide poisoning: three cases.

We examined the usefulness of thiosulfate as an indicator of hydrogen sulfide poisoning by analysing sulfide and thiosulfate in three cases. In the first (non-fatal) case sulfide and thiosulfate were not detected in the blood samples from any of the four workers involved in the accident. In the urine samples, only thiosulfate was detected in three out of the four workers at a concentration of 0.12-0.43 micromol/ml, which was 4-14 times higher than the level in a healthy person. In the second (fatal) case sulfide and thiosulfate were detected in the blood sample at concentrations of 0.007 micromol/ml for sulfide, and 0.025 micromol/ml for thiosulfate. The thiosulfate concentration was at least 8 times higher than the level in a healthy person. In the third (fatal) case sulfide and thiosulfate were detected in the blood sample at concentrations of 0.95 micromol/ml for sulfide, and 0.12 micromol/ml for thiosulfate. Based on the above results, we concluded that thiosulfate in urine is the only indicator to prove hydrogen sulfide poisoning in non-fatal cases, while the analysis of sulfide in fatal cases should be accompanied by the measurement of thiosulfate in blood.

Adult↗

PubMed1996

Determination of cyanide and thiocyanate in blood by gas chromatography and gas chromatography-mass spectrometry.

We devised a sensitive and simple method for determining cyanide and its major metabolite, thiocyanate, in blood using an extractive alkylation technique. Pentafluorobenzyl bromide was used as the alkylating agent, and tetradecyldimethylbenzylammonium chloride was used as the phase-transfer catalyst. The derivatives obtained were analyzed qualitatively by gas chromatography-mass spectrometry and quantitatively by gas chromatography with an electron-capture detection. The detection limits of cyanide and thiocyanate were 0.01 and 0.003 mumol/ml, respectively, while the gross recovery of both compounds was 80%. The calibration curve was linear over the concentration range from 0.02 to 1.0 mumol/ml for cyanide and from 0.01 to 1.0 mumol/ml for thiocyanate. The accuracy and precision of the method were evaluated, and the coefficients of variation were found to be within 10%. Using the method, the blood levels of two victims who had died from cyanide poisoning were determined.

Chromatography, Gas↗

PubMed1996

A case of drowning linked to ingested sulfides--a report with animal experiments.

An adult male was found dead beneath a pool of sewage in the pump room of a fish market. Autopsy revealed the cause of death to be suffocation after aspirating sewage into the respiratory tract. Since hydrogen sulfide gas was detected in the atmosphere at the scene of the accident, gas poisoning was suspected and toxicological analysis of sulfides in body tissues was performed. The concentrations of sulfides in the blood, lung and kidney were 0.95 mumol@ml, 0.22 and 0.38 mumol/g, respectively. These values were remarkably higher than those in previously reported cases involving exposure to hydrogen sulfide gas. Therefore, oral intake of sulfides was assumed and the distribution of sulfides in tissues following oral administration of sodium sulfide solution was examined by means of animal experiments using rats. The concentration of sulfides in the blood from rats following oral intake was much higher than that seen following gas exposure. Based on these results, we concluded that the victim had been exposed to hydrogen sulfide gas and had then collapse into a pool of sewage containing sulfides. The sulfides which were distributed throughout the body tissues had mainly issued from the alimentary tract prior to death by drowning.

Adult↗

PubMed1994

How to diagnose polysulphide poisoning from tissue samples.

We carried out animal experiments to toxicologically verify polysulphide poisoning by analyzing tissue samples. A bathing agent containing calcium polysulphides was administered orally to rats, and then polysulphides and sulphide, the decomposed product of polysulphides, were analyzed by GC and GC/MS. The concentrations of polysulphides (mumol/ml or g) were found to be highest in blood (0.196), followed by the liver (0.051), the lungs (0.018) and kidneys (0.013), but were below the detection limit (0.005 mumol/g) in the other tissues tested. Sulphide was detected in all the tissue samples and was found to be highest in the blood (0.518 mumol/ml), this being 40 times higher than that required for fatal poisoning in the case of hydrogen sulphide. Polysulphide poisoning was considered to be confirmatively diagnosed by detecting and measuring polysuphides and supplementarily sulphide in body tissues, most pertinently in the blood. Two practical cases of suspected poisoning by polysulphides are briefly described.

Animals↗

PubMed1991

Determination of polysulphides in blood by gas chromatography and gas chromatography-mass spectrometry.

A sensitive and simple method to determine polysulphides in human blood, using an extractive alkylation technique and gas chromatography, has been devised. Polysulphides were alkylated with pentafluorobenzyl bromide, and then converted into bis(pentafluorobenzyl)disulphide by desulphuration with potassium cyanide. The disulphide was analysed qualitatively by mass fragmentography and quantitatively by gas chromatography with electron-capture detection. The lower limit of detection was 0.005 mumol/ml. Field testing in a suicide case confirmed the validity of the method.

Alkylation↗

PubMed1991

Forensic analysis of triazolam in human tissues using capillary gas chromatography.

A reliable and sensitive method has been developed to assess the concentrations of the hypnotic drug triazolam in human tissues, including putrefied tissues. The method involves a 3-step solvent extraction, clean-up on a silica gel column and gas chromatography using a nitrogen phosphorus detector and a capillary column. Estazolam was used as an internal standard. The calibration curve was linear over the concentration range 1 ng/g-1 microgram/g and the lower limit of detection was 0.5 ng/g. A forensic study was performed on the toxicological effects of triazolam using putrefied tissues.

Adult↗

PubMed1990

Sulfide concentrations in postmortem mammalian tissues.

Postmortem changes in sulfide concentrations in body tissues were examined in autopsied rats exposed to hydrogen sulfide concentrations of 550 to 650 ppm, and in nonexposed rats and humans. Analyses were made by gas chromatography, following an extractive alkylation. Sulfide concentrations in the blood, liver, and kidneys of rats increased in both the exposed and nonexposed groups, depending on the lapse of time after death. On the other hand, the lung, brain, and muscle showed little or no change in sulfide concentration with elapse of time after death. The data obtained from human tissues were almost the same as those for rats, except data for blood, in which no or little increase of sulfide was observed.

Animals↗

PubMed1988

Extractive alkylation and gas chromatographic analysis of sulfide.

A sensitive analysis of sulfide in blood was established, using an extractive alkylation technique. Pentafluorobenzyl bromide was used as the alkylating agent, tetradecyldimethylbenzylammonium chloride as the phase-transfer catalyst, and potassium dihydrogenphosphate as the buffer to suppress the formation of sulfide. Mass fragmentography was used to identify the sulfide derivative and gas chromatography with an electron capture detector was used for quantitative determination, with the lowest limit of detection being about 0.01 microgram/g. The blood level of rats exposed to hydrogen sulfide was also determined.

Alkylation↗

PubMedDate not supplied

Determination of thiosulfate in body fluids by GC and GC/MS.

A simple and sensitive method to determine thiosulfate in human blood and urine was devised. Thiosulfate was first alkylated with pentafluorobenzyl bromide, with L-ascorbic acid as the stabilizer and sodium chloride as the catalyst. The alkylated thiosulfate was oxidized with iodine to obtain bis(pentafluorobenzyl)disulfide, which was then subjected to gas chromatography and gas chromatography/mass spectrometry. Mass fragmentography was used to identify the disulfide, and gas chromatography with an electron capture detector was used for quantitative determination. The lower limit of detection was 0.003 mumol/mL.

Alkylation↗