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Manami Nishida

Publications and source records attributed to Manami Nishida.

9 recordsLinked to original sources

Miniaturized sample preparation method for determination of amphetamines in urine.

A simple and miniaturized sample preparation method for determination of amphetamines in urine was developed using on-column derivatization and gas chromatography-mass spectrometry (GC-MS). Urine was directly applied to the extraction column that was pre-packed with Extrelut and sodium carbonate. Amphetamine (AP) and methamphetamine (MA) in urine were adsorbed on the surface of Extrelut. AP and MA were then converted to a free base and derivatized to N-propoxycarbonyl derivatives using propylchloroformate on the column. Pentadeuterated MA was used as an internal standard. The recoveries of AP and MA from urine were 100 and 102%, respectively. The calibration curves showed linearity in the range of 0.50-50 microg/mL for AP and MA in urine. When urine samples containing two different concentrations (0.50 and 5.0 microg/mL) of AP and MA were determined, the intra-day and inter-day coefficients of variation were 1.4-7.7%. This method was applied to 14 medico-legal cases of MA intoxication. The results were compared and a good agreement was obtained with a HPLC method.

Amphetamines↗

[Development of salicylic acid detector tube].

A detector tube was successfully devised for the screening of salicylic acid in urine. It, named "salicylic acid detector tube", consists of glass tube in which silica gel coated with 5% (w/w) of ferric chloride is enclosed. A pipette rubber cap was attached to an end of the tube, and another end was inserted into urine sample. The sample was then introduced into the tube, the color of the reagent immediately turned purple under the condition of more than 50 microg/ml of salicylic acid in urine. This device was useful for the emergency screening of salicylic acid in acute poisoning cases with aspirin.

Acute Disease↗

[On-site screening of toxic substances in clinical laboratory and poisoning information system].

An accurate screening system is required to treat acute poisoning patients in clinical toxicology. However, the medical center analysis of poisonous substances using machines is not sufficient. Moreover, the handling and maintenance of such machines are tedious and costly. To improve these problems and employ effective information, we have developed a simple detection method and constructed a support system using the Internet. Various support systems have been attempted for the training of analysts who can cope with a poisoning incident (accident) involving toxic substances. Our simple detection method for toxic substances in the medical center was developed without using expensive analysis apparati. As technical support for the analysts of medical laboratories, the following items were completed: 1) training for analysts, 2) research of analytical techniques in the medical centers (accuracy management), 3) creation of an analysis manual, 4) construction of on-line analysis manuals, 5) construction of the poisoning information system on the Internet, 6) construction of a system for requesting analysis of poisoning, 7) a quick-detection method for toxic substances and 8) examination of the insurance application.

Clinical Laboratory Information Systems↗

[Acetaminophen].

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Acetaminophen↗

[Amphetamines].

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Amphetamine-Related Disorders↗

Routine analysis of amphetamine and methamphetamine in biological materials by gas chromatography-mass spectrometry and on-column derivatization.

A simple determination method of amphetamine (AP) and methamphetamine (MA) in biological materials was developed using on-column derivatization and gas chromatography-mass spectrometry (GC-MS). AP and MA in biological materials were adsorbed on the surface of Extrelut and then extracted and derivatized simultaneously on the Extrelut column. AP and MA were derivatized to the N-propoxycarbonyl derivatives using propylchloroformate. Pentadeuterated MA was used as an internal standard. The recoveries of AP and MA from urine were 88.2 and 92.5%, and those from blood were 89.7 and 90.3%, respectively. The calibration curves showed linearity in the range of 12.5-2000 ng/ml (ng/g) for AP and MA in urine and blood, and 0.25-20 ng/mg in hair. When urine samples containing two different concentrations (200 and 1000 ng/ml) of AP and MA, blood samples containing two different concentrations (200 and 1000 ng/g) of AP and MA, hair samples containing two different concentrations (0.5 and 5.0 ng/mg) of AP and MA, the coefficients of variation of intra-day and inter-day were 0.68-3.60% in urine, 0.42-4.58% in blood, and 1.20-13.1% in hair. Furthermore, this proposed method was applied to a medico-legal case of MA intoxication.

Adult↗

Direct extract derivatization for determination of amino acids in human urine by gas chromatography and mass spectrometry.

The purpose of this study was to develop a simple and accurate analytical method to determine amino acids in urine samples. The developed method involves the employment of an extract derivatization technique together with gas chromatography-mass spectrometry (GC-MS). Urine samples (300 microl) and an internal standard (10 microl) were placed in a screw tube. Ethylchloroformate (50 microl), methanol-pyridine (500 microl, 4:1, v/v) and chloroform (1 ml) were added to the tube. The organic layer (1 microl) was injected to a GC-MS system. In this proposed method, the amino acids in urine were derivatized during an extraction, and the analytes were then injected to GC-MS without an evaporation of the organic solvent extracted. Sample preparation was only required for ca. 5 min. The 15 amino acids (alanine, aspartic acid, cysteine, glutamic acid, glycine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, proline, tyrosine, tryptophan, valine) quantitatively determined in this proposed method. However, threonine, serine, asparagine, glutamine, arginine were not derivatized using any tested derivatizing reagent. The calibration curves showed linearity in the range of 1.0-300 microg/ml for each amino acid in urine. The correlation coefficients of the calibration curves of the tested amino acids were from 0.966 to 0.998. The limit of detection in urine was 0.5 microg/ml except for aspartic acid. This proposed method demonstrated substantial accuracy for detection of normal levels. This proposed method was limited for the determination of 15 amino acids in urine. However, the sample preparation was simple and rapid, and this method is suitable for a routine analysis of amino acids in urine.

Amino Acids↗

On-column derivatization for determination of amphetamine and methamphetamine in human blood by gas chromatography-mass spectrometry.

A simple determination method of amphetamine (AP) and methamphetamine (MA) in human blood was developed using on-column derivatization and gas chromatography-mass spectrometry (GC-MS). AP and MA were adsorbed on the surface of Extrelut and then derivatized the N-propoxycarbonyl derivatives using propylchloroformate. Pentadeuterated MA was used as an internal standards. The recoveries of AP and MA from the spiked blood were 89.7 and 90.3%, respectively. The calibration curves showed linearity in the range of 12.5-2000 ng/g for AP and MA in blood. The coefficients of variation of intraday and interday were 0.42-4.58%. Furthermore, this proposed method was applied to some medico-legal cases of MA intoxication. MA and its metabolite AP were detected in the blood samples, and the correlation of the blood level of amphetamines and the behaviors of the victims was in good agreement with the criteria proposed by Nagata [Jpn. J. Legal Med. 37 (1983) 513].

Adult↗

Acute liver failure following intravenous methamphetamine.

A 41-y-o Pakistani man presented with psychosis, hyperthermia, rhabdomyolysis, and liver dysfunction approximately 6 h after i.v. injection of methamphetamine. Serum concentrations of methamphetamine and amphetamine on admission were 0.30 microg/mL and 0.04 microg/mL, respectively. Total serum bilirubin and alanine aminotransferase concentrations peaked on the 3rd hospital day at 8.6 mg/dL and 4155 IU/L, respectively, and gradually returned to normal with supportive care. The patient had no evidence of infectious hepatitis or intake of other drugs. Histologic examination of a liver biopsy specimen obtained on the 11th d showed confluent necrosis and ballooning degeneration in centrilobular zones. No inflammatory changes were seen in portal tracts. Liver damage can be a complication of illicit methamphetamine use, even in patients without viral infection or intake of other drugs.

Adult↗