Chiba, Japan

Chiba Institute of Science is a private university in Chōshi, Chiba, Japan, established in 2004. Wikipedia.

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Igarashi K.,Chiba University | Igarashi K.,Amine Pharma Research Institute | Kashiwagi K.,Chiba Institute of Science
International Journal of Biochemistry and Cell Biology | Year: 2010

Polyamines (putrescine, spermidine and spermine) are essential for normal cell growth. The polyamine levels in cells are regulated by biosynthesis, degradation, and transport. Polyamines can modulate the functions of DNA, nucleotide triphosphates, proteins, and especially RNA because most polyamines exist in a polyamine-RNA complex in cells. Thus, the major focus on this review is on the role of polyamines in protein synthesis. In addition, effects of polyamines on B to Z conversion of DNA, transcription, phosphorylation of proteins, cell cycle progression, apoptosis and ion channels, especially NMDA receptors, are outlined. The function of eIF5A is also briefly discussed. Finally, a correlation between acrolein, produced from polyamines by polyamine oxidases, and chronic renal failure or brain stroke is summarized. Increased levels of polyamine oxidases and acrolein are good markers of chronic renal failure and brain stroke. © 2009 Elsevier Ltd. All rights reserved.

Igarashi K.,Chiba University | Kashiwagi K.,Chiba Institute of Science
Molecular Nutrition and Food Research | Year: 2011

The relationship between acrolein (CH 2=CH-CHO) and brain infarction is the focus of this review. It has been found that acrolein is produced mainly within cells from polyamines by polyamine oxidases (PAOs), especially from spermine by spermine oxidase during cell damage, and that acrolein is more toxic than reactive oxygen species (ROS) in a cell culture system. Thus, the possibility that acrolein and PAOs are good biochemical markers of stroke was tested because there are no other reliable biochemical markers at the early stage of stroke. Levels of protein-conjugated acrolein (PC-Acro) and PAOs (acrolein-producing enzymes) were significantly increased in the plasma of stroke patients. The multiplied value of PC-Acro by PAOs was nearly parallel with the size of stroke. Furthermore, when the combined measurements of PC-Acro, interleukin-6 (IL-6) and C-reactive protein (CRP) were evaluated along with age using a receiver operating characteristic (ROC) curve, even silent brain infarction (SBI), which is a small brain infarction, was indicated with approximately 84% sensitivity and specificity. These findings clearly indicate that acrolein is strongly correlated with cell damage during brain infarction. © 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim.

Matsuda I.,Chiba Institute of Science | Nittono H.,Hiroshima University
Clinical Neurophysiology | Year: 2015

Objective: The interaction between affective and cognitive processes has been examined using the late positive potential (LPP) component of the event-related brain potential. The LPP is elicited not only by affective stimuli but also by nonaffective stimuli that require effortful cognitive processing. However, it is unclear whether these LPPs are equivalent. The present study decomposed the LPP into subcomponents that responded differently to affective content and cognitive demands. Methods: The participants (N= 21) performed four types of revised oddball tasks, in which one affective and five nonaffective pictures were presented. For one of the nonaffective pictures, different cognitive demands were loaded: viewing the display, updating a count, updating two different items, or concealing knowledge of the picture. Results: A temporal-spatial principal component analysis revealed two major subcomponents of the LPP. The central-parietal subcomponent was elicited by affective stimuli, whereas the occipital subcomponent was elicited by nonaffective stimuli with cognitive demands in the two-item updating and concealment conditions. Conclusions: The results suggest that the central-parietal dominant LPP may reflect motivated attentional processing, whereas the occipital dominant LPP may reflect effortful controlled processing. Significance: Dealing with these two LPP subcomponents separately may be useful for examining the interaction between affective and cognitive processing of stimuli. © 2014 International Federation of Clinical Neurophysiology.

Kashiwagi K.,Chiba Institute of Science
Methods in molecular biology (Clifton, N.J.) | Year: 2011

Polyamine content in cells is regulated by biosynthesis, degradation, and transport. With regard to transport, uptake and excretion proteins exist in Escherichia coli and Saccharomyces cerevisiae. In E. coli, the uptake systems comprise a spermidine-preferential uptake system consisting of the PotA, B, C, and D proteins, and a putrescine-specific uptake system consisting of the PotF, G, H, and I proteins. Two other proteins, PotE and CadB, each containing 12 transmembrane segments, function as antiporters (putrescine-ornithine and cadaverine-lysine) and are important for cell growth at acidic pH. MdtJI was identified as a spermidine excretion system. When putrescine was used as energy source, PuuP functioned as a putrescine transporter. In S. cerevisiae, DUR3 and SAM3, containing 16 or 12 transmembrane segments, are the major polyamine uptake proteins, whereas TPO1 and TPO5, containing 12 transmembrane segments, are the major polyamine excretion proteins, and UGA4 is a putrescine transporter on the vacuolar membrane. The activities of DUR3 and TPO1 are regulated by phosphorylation of serine/threonine residues. The identification and assay procedures of these transporters are described in this chapter.

Kanamori-Kataoka M.,Chiba Institute of Science
Journal of mass spectrometry : JMS | Year: 2011

Ricin is a glycosylated proteinous toxin that is registered as toxic substance by Chemical Weapons convention. Current detection methods can result in false negatives and/or positives, and their criteria are not based on the identification of the protein amino acid sequences. In this study, lactose-immobilized monolithic silica extraction followed by tryptic digestion and liquid chromatography/mass spectrometry (LC/MS) was developed as a method for rapid and accurate determination of ricin. Lactose, which was immobilized on monolithic silica, was used as a capture ligand for ricin extraction from the sample solution, and the silica was supported in a disk-packed spin column. Recovery of ricin was more than 40%. After extraction, the extract was digested with trypsin and analyzed by LC/MS. The accurate masses of molecular ions and MS/MS spectra of the separated peptide peaks were measured by Fourier transform-MS and linear iontrap-MS, respectively. Six peptides, which were derived from the ricin A-(m/z 537.8, 448.8 and 586.8) and B-chains (m/z 701.3, 647.8 and 616.8), were chosen as marker peptides for the identification of ricin. Among these marker peptides, two peptides were ricin-specific. This method was applied to the determination of ricin from crude samples. The monolithic silica extraction removed most contaminant peaks from the total ion chromatogram of the sample, and the six marker peptides were clearly detected by LC/MS. It takes about 5 h for detection and identification of more than 8 ng/ml of ricin through the whole handling, and this procedure will be able to deal with the terrorism using chemical weapon. Copyright © 2011 John Wiley & Sons, Ltd.

Amphetamine-type stimulants (ATS) such as methamphetamine are widely abused and can cause toxic effects in the body. In this study, a simple and accurate analytical method for distribution measurement of drugs in organs was developed to visualize localization of ATS in organs and to complement drug distribution by mass spectrometry imaging (MSI). The brain, liver and kidney from rats to which ATS had been administered were segmented into blocks of 2×2×2 mm3 at -30°C. Each organ block was micropulverized with a stainless-steel bullet at -80°C. The concentrations of drugs in each block were measured by liquid chromatography/tandem mass spectrometry. The three-dimensional distribution of drugs in a whole organ was expressed using color gradation of drug concentration after reconstruction of all blocks to the original locations. The distribution was also compared with that obtained by MSI. This method enabled measurement of drug distribution in organs with simple and clean procedures and accurate quantification unlike autoradiography and MSI. The methamphetamine concentrations were different between parts in an organ, particularly in the kidney. This method could be applicable to the measurement of the distribution of compounds in various solid samples and could be used as a complementary method for the measurement of the distribution of compounds by MSI. Copyright © 2011 John Wiley & Sons, Ltd.

Akutsu T.,Chiba Institute of Science
International journal of legal medicine | Year: 2010

Statherin is a low molecular-weight phosphoprotein secreted from the parotid gland. Statherin mRNA was previously reported to be a useful marker for mRNA-based saliva identification. In this study, applicability of ELISA detection of statherin for forensic identification of saliva was investigated. The specificity and sensitivity of ELISA for detection of statherin were compared with those of ELISA for α-amylase and the Phadebas® amylase test. Statherin was specifically detected in saliva but not in other body fluids. In addition, statherin was successfully detected in aged saliva stains, mixed body fluids-saliva stains, and simulated casework samples. On the other hand, although ELISA for α-amylase showed higher sensitivity than ELISA for statherin, it was not specific enough to identify saliva. The Phadebas® amylase test also showed positive results in other body fluids that are known to have α-amylase activity; however, it is easy to use for screening forensic casework samples. In conclusion, ELISA for detection of statherin developed in this study could be an effective tool for the forensic identification of saliva because of its specificity for saliva among other body fluids. Forensic casework samples should be tested by ELISA detection or mRNA-based analysis for statherin, depending on the condition of the sample, to supplement presumptive tests for α-amylase, such as the Phadebas® amylase test.

An LTQ Orbitrap XL hybrid mass spectrometry method was developed for the determination of illicit drugs and their metabolites, including amphetamine (AP), methamphetamine (MA), dimethylamphetamine (DMA), 3,4- methylenedioxyamphetamine (MDA), 3,4-methylenedioxymethamphetamine (MDMA), ketamine (KET), norketamine (NK), cocaine (COC) and benzoylecgonine (BE), in hair. Micropulverized extraction was employed for sample preparation using a small hair sample (2 cm piece or 0.2 mg). Recoveries of the analytes during sample preparation were estimated using fortified hair samples and ranged from 35.5% for COC to 71.7% for AP. High resolution full-scan mass spectra and unit resolution product-ion spectra were obtained with the Orbitrap analyzer and the linear ion-trap analyzer, respectively. High-resolution extracted ion chromatograms at a tolerance of 3 ppm were utilized for quantification. The analytes were identified using the product-ion spectra in combination with the accurate masses of the corresponding protonated molecules observed in the high-resolution mass spectra. Lower limits of quantification obtained from a 0.2 mg hair sample were 0.050 ng mg -1 (MDMA, KET and BE), 0.10 ng mg -1 (AP, MA, DMA, NK and COC) and 0.50 ng mg -1 (MDA). Two reference materials were analyzed for verification, and segmental analysis of single strands of hair specimens from actual cases was performed. © The Royal Society of Chemistry 2011.

A rapid extraction method for psychoactive drugs from hair is developed.A short extraction time (10min) is achieved through micropulverized extraction.Recoveries are superior to existing methods with phosphate buffer or methanol.Zolpidem analysis in hair was established based on the developed method. A micropulverization method for rapid extraction of psychoactive drugs from hair was developed. A hair sample (10. mg) was micropulverized for 10. min at 42. Hz with 0.2. mL of 45% (w/v) aqueous ammonium phosphate (pH 8.4). Liquid-liquid extraction was carried out in the same tube using acetonitrile, and the organic layer was removed and filtered. Conventional methods, including solid-liquid extraction with an ammonium phosphate solution or methanol, were also employed, and the relative extraction efficiencies of amitriptyline, nortriptyline, norfludiazepam, flunitrazepam, 7-aminoflunitrazepam, mianserin and zolpidem with these methods from an incurred human hair specimen were compared using liquid chromatography/tandem mass spectrometry. The highest extraction efficiencies for all the analytes were achieved using the method developed here, even though the extraction time (10. min) was short. Overnight methanol extraction has frequently been used for hair analysis; however, the extraction efficiency was not sufficient for amines. The method was successfully applied to the quantification of zolpidem in human hair. The range of quantification was 1-25,000. pg/mg, and interday accuracy and precision (. n=. 5) at three concentrations were 1.8-8.8% and 3.3-8.1%, respectively. The developed method was applied to three actual (incurred) samples, for which the concentrations of zolpidem were determined to be 78.9-18,300 (pg/mg). © 2013 Elsevier B.V..

Seto Y.,Chiba Institute of Science
Journal of Health Science | Year: 2011

Biological and chemical warfare agents (BCWAs) are diverse in nature including synthetic low molecular weight chemical warfare agents (gaseous choking and blood agents), volatile nerve gases and blister agents, nonvolatile vomit agents and lachrymators, biological toxins (polar lowmolecular weight toxins and proteinous toxins), and microorganisms (viruses, rickettsia, chlamydia and bacteria). In the consequencemanagement against chemical and biological warfare terrorism, speedy decontamination of casualties, goods, items and equipments, buildings and field is required for the minimization of the terrorism damage. At present, washing casualties and contaminatedmaterials with large volumes of water is the basic way, and hypochlorite solution is mainly used to decompose BCWAs. However, it still remains unsolved how to dispose the waste water contaminated with BCWAs, and decontaminating reagents have serious problems of high toxicity to human, despoiling nature to environment, long finishing time and non-durability. In addition, the present decontamination technologies are not effective, nonspecifically affecting the surrounding non-target materials. Therefore, it is the urgent matter to build up usable decontamination system surpassing the present system. The author introduces the joint project of research and development of the novel decontamination system against BCWAs, in the purpose of realizing non-dangerous, rapid, specific, effective and economical on-site decontamination. The project consists of establishment of the evaluation methods for decontamination, and verification of the present technologies and utilization of bacterial organophosphorus hydrolase, development of specific adsorptive elimination technologies using molecular recognition devices, and development of deactivation technologies using photocatalysis. © 2011 The Pharmaceutical Society of Japan.

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