15 results on '"Shuntaro Matsuta"'
Search Results
2. Urinary excretion profiles of etizolam and its main metabolites after a single oral dose
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Misato Wada, Noriaki Shima, Tooru Kamata, Shuntaro Matsuta, Akari Ishikawa, Atsushi Nitta, Ryutaro Asai, Hidenao Kakehashi, Shihoko Fujii, Keiko Sasaki, Hiroe Kamata, and Munehiro Katagi
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Single oral dose ,Urinary excretion ,business.industry ,Medicine ,General Medicine ,Etizolam ,Pharmacology ,business ,medicine.drug - Published
- 2021
3. Development and demonstration of cannabis DNA detection kit using DNA chromatography chip
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Shuntaro Matsuta, Kenji Tsujikawa, Tatsuyuki Kanamori, Naoki Tachiiri, Hiroki Segawa, Miyamoto Shigehiko, Kenji Kuwayama, Yuko T. Iwata, Tadashi Yamamuro, Hiroyuki Inoue, and Ayumu Ishii
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Dna detection ,chemistry.chemical_compound ,Chromatography ,biology ,Chemistry ,Cannabis ,Chip ,biology.organism_classification ,DNA - Published
- 2021
4. Development of a new method for cyanide determination using dimethoxytriazinyl (DMT) derivatization
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Tooru Kamata, Misato Wada, Noriaki Shima, Shihoko Nakano, Keiko Sasaki, Hiroe Kamata, Akari Ishikawa, Hiroshi Nishioka, Munehiro Katagi, Atsushi Nitta, Hidenao Kakehashi, Ryutaro Asai, Akihiro Miki, and Shuntaro Matsuta
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chemistry.chemical_compound ,Chromatography ,chemistry ,Cyanide ,Gas chromatography–mass spectrometry ,Derivatization - Published
- 2020
5. Discrimination between internal and external uses by analysis of urine and blood from diphenhydramine users
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Akari Ishikawa, Hiroshi Nishioka, Misato Wada, Atsushi Nitta, Shihoko Nakano, Hiroe Kamata, Shuntaro Matsuta, Ryutaro Asai, Tooru Kamata, Akihiro Miki, Noriaki Shima, Munehiro Katagi, Keiko Sasaki, and Hidenao Kakehashi
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business.industry ,Anesthesia ,Diphenhydramine ,medicine ,Urine ,business ,medicine.drug - Published
- 2020
6. Development of the Exact Mass Database of Surfactants and Its Forensic Application
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Shihoko Nakano, Noriaki Shima, Toru Kamata, Hitoshi Tsuchihashi, Akihiro Miki, Hiroshi Nishioka, Keiko Sasaki, Shuntaro Matsuta, Munehiro Katagi, Hidenao Kakehashi, and Hiroe Kamata
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Mass ,Information retrieval ,Development (topology) ,Computer science - Published
- 2019
7. Human and rat microsomal metabolites of N-tert-butoxycarbonylmethamphetamine and its urinary metabolites in rat
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Akihiro Miki, Atsushi Nitta, Ryutaro Asai, Hiroshi Nishioka, Hiroe Kamata, Noriaki Shima, Hidenao Kakehashi, Takahiro Doi, Misato Wada, Tooru Kamata, Shuntaro Matsuta, Keiko Sasaki, Shihoko Fujii, Akari Miyake, Munehiro Katagi, and Hiroshi Hasegawa
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Chromatography ,Chemistry ,Biochemistry (medical) ,Urine ,Metabolism ,Toxicology ,Pathology and Forensic Medicine ,Rats ,Body Fluids ,Methamphetamine ,Excretion ,Hydroxylation ,Metabolic pathway ,chemistry.chemical_compound ,Glucuronides ,Microsome ,Microsomes, Liver ,Ingestion ,Humans ,Animals ,Urinary Tract ,Incubation ,Chromatography, Liquid - Abstract
Purpose N-tert-Butoxycarbonylmethamphetamine (BocMA), a masked derivative of methamphetamine (MA), converts into MA under acidic condition and potentially acts as a precursor to MA following ingestion. To investigate the metabolism and excretion of BocMA, metabolism tests were conducted using human liver microsomes (HLM), rat liver microsomes (RLM) and rat. Methods BocMA metabolites were analyzed after 1000-ng/mL BocMA incubation with microsomes for 3, 8, 13, 20, 30, and 60 min. Rats were administered intraperitoneal injections (20 mg/kg) of BocMA and their urine was collected in intervals for 72 h. Metabolites were detected by liquid chromatography–tandem mass spectrometry with five authentic standards. Results Several metabolites including 4-hydroxy-BocMA, N-tert-butoxycarbonylephedrine and N-tert-butoxycarbonyl-cathinone were detected for HLM and RLM. In the administration test, three glucuronides of hydroxylated metabolites were detected. The total recovery values of BocMA and the metabolites during the first 72 h accounted for only 0.3% of the administered dose. Throughout the microsomal and administration experiments, MAs were not detected. Conclusion Hydroxylation, carbonylation and N-demethylation were proposed as metabolic pathways. However, BocMA and phase I metabolites were hardly detected in urine. This study provides useful information to interpret the possibility of BocMA intake as the cause of MA detection in biological sample.
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- 2021
8. Incorporation of Methoxyphenamine into Hair in Early Stage after Intake
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Takako Sato, Ryutaro Asai, Akari Ishikawa, Shihoko Fujii, Hitoshi Tsuchihashi, Shuntaro Matsuta, Misato Wada, Noriaki Shima, Hiroe Kamata, Akihiro Miki, Atsushi Nitta, Hidenao Kakehashi, Keiko Sasaki, Tooru Kamata, Munehiro Katagi, and Hiroshi Nishioka
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medicine.medical_specialty ,Health, Toxicology and Mutagenesis ,Urine ,Toxicology ,Analytical Chemistry ,Methamphetamine ,chemistry.chemical_compound ,Black hair ,Dermis ,Oral administration ,Internal medicine ,medicine ,Environmental Chemistry ,Chemical Health and Safety ,integumentary system ,Methoxyphenamine ,Bulb ,Substance Abuse Detection ,Endocrinology ,medicine.anatomical_structure ,Hair root ,chemistry ,medicine.drug ,Chromatography, Liquid ,Hair - Abstract
In order to investigate the incorporation behavior of drugs into hair in early stage (within 24 h) after intake, time-course changes in drug distribution in black hair were carefully analyzed after a single oral administration of methoxyphenamine (MOP), a non-regulated analog of methamphetamine. Single-hair specimens collected by plucking with the roots intact at appropriate intervals post-intake were each divided into 1-mm segments from the proximal end, and MOP in each segment was determined by a validated liquid chromatography–tandem mass spectrometry procedure. At 10 min after intake, MOP was not detected in any of the segments. MOP became detectable 30 min after intake in the hair bulb (0–1-mm segment from the proximal end) and 1 h after intake in the upper dermis zone (1–2-mm to 4–5-mm segments). The amount of MOP in the hair bulb increased rapidly over 3 h after intake and reached a maximum concentration of ∼100–900 pg/1-mm single hair (11–95 ng/mg) around 3–10 h after intake, whereas that in the upper dermis zone increased at a more gradual pace over 24 h and reached a plateau at ∼30–100 pg/1-mm hair (3–11 ng/mg). These differences can be attributed to the different incorporation mechanisms of the drug. Results from this study can further elucidate the drug incorporation mechanism, which is crucial for accurately interpreting results in hair analyses. Our findings also suggest that hair drug analysis with special attention to the hair root can serve as a useful complementary approach to urine- and blood-based testing in the field of forensic toxicology.
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- 2020
9. A new method for detection of nitrous oxide using azo coupling reaction
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Hiroshi Nishioka, Ryutaro Asai, Shihoko Nakano, Hidenao Kakehashi, Tooru Kamata, Shuntaro Matsuta, Misato Wada, Akihiro Miki, Noriaki Shima, Munehiro Katagi, and Atsushi Nitta
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chemistry.chemical_compound ,Chemistry ,010401 analytical chemistry ,Inorganic chemistry ,Nitrous oxide ,Azo coupling ,010402 general chemistry ,Photochemistry ,01 natural sciences ,0104 chemical sciences - Published
- 2018
10. Effects of lipophilicity and functional groups of synthetic cannabinoids on their blood concentrations and urinary excretion
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Keiko Sasaki, Misato Wada, Shuntaro Matsuta, Atsushi Nitta, Akihiro Miki, Ryutaro Asai, Hiroe Kamata, Hiroshi Nishioka, Munehiro Katagi, Noriaki Shima, Tooru Kamata, Shihoko Nakano, Hidenao Kakehashi, and Akari Ishikawa
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Octanol ,Octanols ,Chromatography ,medicine.drug_class ,Cannabinoids ,Water ,Carboxamide ,Urine ,Pathology and Forensic Medicine ,Partition coefficient ,chemistry.chemical_compound ,Pharmacokinetics ,chemistry ,Valine ,Tandem Mass Spectrometry ,Lipophilicity ,Synthetic cannabinoids ,medicine ,Humans ,Law ,medicine.drug ,Chromatography, Liquid - Abstract
The influence of lipophilicity and functional groups of synthetic cannabinoids (SCs) on their blood concentrations and urinary excretion has been studied by analyzing blood and urine specimens sampled from drivers who were involved in a car crashes under the influence of SCs. A total of 58 specimens (26 urine and 31 blood specimens), sampled within 13h of the occurrence, were analyzed by liquid chromatography-tandem mass spectrometry. Fifteen SCs were detected in those specimens; the SCs detected were categorized as follows: Class 1, Naphthoyl/Benzoyl indole (EAM2201 and three other analogs); Class 2, Indole-3-carboxylate/carboxamide containing naphthol/quinol (5F-PB-22 and four other analogs); and Class 3, Indazole-3-carboxamide containing valine/tert-leucine derivative (5F-AMB and five other analogs). The calculated lipophilicity index log P, the octanol/water participation coefficient, of those SCs in Classes 1, 2, and 3 ranged between 5.01-8.14, 5.80-6.74 and 2.29-3.81, respectively. Class 3 SCs were detectable in 12 out of 13 urine specimens, but those in Classes 1 and 2 were not detected in urine. Our analytical results indicated that the boundary line for their detectability in urine lies between log P 4 and 5. The blood concentrations of Class 3 SCs varied widely (0.0036-31ng/ml) depending on their log P, while much smaller variation was observed among those in Class 2 (0.10-5.0ng/ml).
- Published
- 2019
11. Incorporation of zolpidem and methoxyphenamine into white hair strands after single administrations: Influence of hair pigmentation on drug incorporation
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Shuntaro Matsuta, Ryutaro Asai, Shihoko Nakano, Noriaki Shima, Tooru Kamata, Hiroe Kamata, Akihiro Miki, Atsushi Nitta, Hitoshi Tsuchihashi, Akari Ishikawa, Hidenao Kakehashi, Misato Wada, Takako Sato, Munehiro Katagi, and Keiko Sasaki
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Drug ,Male ,Narcotics ,medicine.medical_specialty ,Zolpidem ,Time Factors ,media_common.quotation_subject ,01 natural sciences ,Pathology and Forensic Medicine ,Methamphetamine ,03 medical and health sciences ,chemistry.chemical_compound ,Forensic Toxicology ,0302 clinical medicine ,Dermis ,Tandem Mass Spectrometry ,Internal medicine ,otorhinolaryngologic diseases ,medicine ,Humans ,Hypnotics and Sedatives ,030216 legal & forensic medicine ,Hair Color ,media_common ,integumentary system ,Methoxyphenamine ,Chemistry ,010401 analytical chemistry ,Hair analysis ,Middle Aged ,Mass spectrometric ,0104 chemical sciences ,White (mutation) ,Substance Abuse Detection ,Endocrinology ,medicine.anatomical_structure ,Hair root ,sense organs ,Law ,medicine.drug ,Chromatography, Liquid ,Hair - Abstract
In order to investigate the influence of pigmentation on the incorporation of drugs into hair, time-course changes in drug distribution along non-pigmented (white) hairs as well as pigmented (black) hairs plucked from the same subject was observed following single administrations of two basic drugs with different properties, zolpidem and methoxyphenamine. These drugs in 1-mm sections of single hair specimens were each determined by a liquid chromatography–tandem mass spectrometric procedure. During the early stage (12–36 h) after intake, for black hairs, both drugs were detected over the entire area of hair root (4–5 mm in length), in which notable concentration of these drugs in the hair bulb (0–1-mm segment from the bottom of hair root, Region 1) and lower concentrations in the upper dermis zone (1–2-mm to 3–4-mm or to 4–5-mm segments, Region 2) were commonly observed. Meanwhile, for white hairs, high drug concentrations in Region 1 as detected in black hairs were not observed although only small amounts of these drugs were detected over Region 2. Subsequent time-course changes in the concentration of drugs in hair demonstrated that the drugs once incorporated into white hair via Region 2 decreased gradually over the period from 24 h to 35 days after intake, but those of black hairs remained almost unchanged. These findings revealed here suggest that hair pigments have two important roles in the distribution of drugs: (1) incorporation of drugs into hair via Region 1, and (2) retention of already incorporated drugs in the hair tissue. These findings would be useful for discussing individual drug-use history based on hair analysis in the forensic fields.
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- 2019
12. Structural characterization of cathinone-type designer drugs by EI mass spectrometry
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Shuntaro Matsuta, Hiroe Kamata, Akihiro Miki, Hitoshi Tsuchihashi, Tooru Kamata, Keiko Sasaki, Koichi Suzuki, Kento Tsuboi, Hiroshi Nishioka, Michiaki Tatsuno, Noriaki Shima, Kei Zaitsu, and Munehiro Katagi
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Designer drug ,Chromatography ,Cathinone ,medicine.drug_class ,Chemistry ,medicine ,Mass spectrometry ,medicine.drug ,Characterization (materials science) - Published
- 2014
13. Metabolism of the designer drug α-pyrrolidinobutiophenone (α-PBP) in humans: identification and quantification of the phase I metabolites in urine
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Takako Sato, Shuntaro Matsuta, Munehiro Katagi, Kei Zaitsu, Hidenao Kakehashi, Akihiro Miki, Hitoshi Tsuchihashi, Hiroe Kamata, Noriaki Shima, Shihoko Nakano, Keiko Sasaki, Tooru Kamata, Koichi Suzuki, and Hiroshi Nishioka
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chemistry.chemical_classification ,Propiophenones ,Chromatography ,Ketone ,Pyrrolidines ,medicine.drug_class ,Diastereomer ,Pyrrolidine ,Gas Chromatography-Mass Spectrometry ,Pathology and Forensic Medicine ,Designer Drugs ,Designer drug ,chemistry.chemical_compound ,Metabolic pathway ,chemistry ,Tandem Mass Spectrometry ,medicine ,Humans ,Gas chromatography–mass spectrometry ,Glucuronide ,Law ,Drug metabolism ,Chromatography, Liquid - Abstract
Urinary phase I metabolites of α-pyrrolidinobutiophenone (α-PBP) in humans were investigated by analyzing urine specimens obtained from drug abusers. Unequivocal identification and accurate quantification of major metabolites were realized using gas chromatography–mass spectrometry and liquid chromatography–tandem mass spectrometry with newly synthesized authentic standards. Two major phase I metabolic pathways were revealed: (1) reduction of the ketone group to 1-phenyl-2-(pyrrolidin-1-yl)butan-1-ol (OH-α-PBP, diastereomers) partly followed by conjugation to its glucuronide and (2) oxidation at the 2″-position of the pyrrolidine ring to α-(2″-oxo-pyrrolidino)butiophenone (2″-oxo-α-PBP) via the putative intermediate α-(2″-hydroxypyrrolidino)butiophenone (2″-OH-α-PBP). Of the phase I metabolites retaining the structural characteristics of the parent drug, OH-α-PBP was the most abundant in all specimens examined. Comparison of the phase I metabolism of α-PBP and α-pyrrolidinovalerophenone (α-PVP) suggested a relationship between the aliphatic side chain length and the metabolic pathways in α-pyrrolidinophenones: the shorter aliphatic side chain (1) led to more extensive metabolism via reduction of the ketone group than via the oxidation at the 2″-position of the pyrrolidine ring and (2) influenced the isomeric ratio of a pair of diastereomers.
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- 2014
14. Development of a simple one-pot extraction method for various drugs and metabolites of forensic interest in blood by modifying the QuEChERS method
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Keiko Nakanishi, Hitoshi Tsuchihashi, Koichi Suzuki, Akihiro Miki, Tooru Kamata, Shuntaro Matsuta, Noriaki Shima, Hiroshi Nishioka, Kei Zaitsu, Michiaki Tatsuno, Munehiro Katagi, and Kento Tsuboi
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Analyte ,Acetonitriles ,Metabolite ,Sodium Chloride ,Quechers ,Gas Chromatography-Mass Spectrometry ,Pathology and Forensic Medicine ,chemistry.chemical_compound ,Forensic Toxicology ,Magnesium Sulfate ,Liquid chromatography–mass spectrometry ,medicine ,Humans ,Desiccation ,Blood Coagulation ,Whole blood ,Acetic Acid ,Chromatography ,Chemistry ,Brotizolam ,Extraction (chemistry) ,Solid Phase Extraction ,Pharmaceutical Preparations ,Solvents ,Indicators and Reagents ,Gas chromatography–mass spectrometry ,Law ,medicine.drug ,Chromatography, Liquid - Abstract
A rapid and convenient extraction method has been developed for the determination of various drugs and metabolites of forensic interest in blood by modifying the dispersive solid-phase extraction method "QuEChERS". The following 13 analytes with various chemical properties were used for the method development and its validation: amphetamine, methamphetamine, zolpidem, the carboxylate-form major metabolite of zolpidem M-1, flunitrazepam, 7-aminoflunitrazepam, phenobarbital, triazolam, α-hydroxytriazolam, brotizolam, α-hydroxybrotizolam, chlorpromazine, and promethazine. The modification of the QuEChERS method includes the use of relatively large amounts of inorganic salts in order to coagulate blood, which allows easy isolation of the organic extract phase. A combination of 100 mg anhydrous magnesium sulfate as a dehydrating agent, 50mg sodium chloride as a salting-out agent, and 500 μL acetonitrile containing 0.2% acetic acid as the organic solvent provided the optimum conditions for processing a 100 μL whole blood sample. The recoveries of the analytes spiked into whole blood at 0.5 μg/mL ranged between 59% and 93%. Although the addition of the graphitized carbon Envi-carb for cleanup decreased the recoveries of zolpidem and its carboxylate-form metabolite M-1, it was very effective in avoiding interferences by cholesterol. The present method can provide a rapid, effective, user-friendly, and relatively hygienic method for the simultaneous extraction of a wide range of drugs and metabolites in whole blood specimens.
- Published
- 2013
15. Metabolism of the designer drug α-pyrrolidinobutiophenone (α-PBP) in humans: Identification and quantification of the phase I metabolites in urine.
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Shuntaro Matsuta, Noriaki Shima, Hiroe Kamata, Hidenao Kakehashi, Shihoko Nakano, Keiko Sasaki, Tooru Kamata, Hiroshi Nishioka, Akihiro Miki, Munehiro Katagi, Kei Zaitsu, Takako Sato, Hitoshi Tsuchihashi, and Koichi Suzuki
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DESIGNER drugs , *STIMULANTS , *DRUG metabolism , *URINALYSIS , *GAS chromatography/Mass spectrometry (GC-MS) , *KETONES - Abstract
Urinary phase I metabolites of α-pyrrolidinobutiophenone (α-PBP) in humans were investigated by analyzing urine specimens obtained from drug abusers. Unequivocal identification and accurate quantification of major metabolites were realized using gas chromatography-mass spectrometry and liquid chromatography-tandem mass spectrometry with newly synthesized authentic standards. Two major phase I metabolic pathways were revealed: (1) reduction of the ketone group to 1-phenyl-2-(pyrrolidin-1-yl)butan-1-ol (OH-α-PBP, diastereomers) partly followed by conjugation to its glucuronide and (2) oxidation at the 200-position of the pyrrolidine ring to α-(200-oxo-pyrrolidino)butiophenone (200-oxo-α-PBP) via the putative intermediate α-(200-hydroxypyrrolidino)butiophenone (200-OH-α-PBP). Of the phase I metabolites retaining the structural characteristics of the parent drug, OH-α-PBP was the most abundant in all specimens examined. Comparison of the phase I metabolism of α-PBP and α-pyrrolidinovalerophenone (α-PVP) suggested a relationship between the aliphatic side chain length and the metabolic pathways in apyrrolidinophenones: the shorter aliphatic side chain (1) led to more extensive metabolism via reduction of the ketone group than via the oxidation at the 200-position of the pyrrolidine ring and (2) influenced the isomeric ratio of a pair of diastereomers. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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