502 results match your criteria: "National Research Institute of Police Science.[Affiliation]"

Purpose: The usefulness of hepatocytes isolated from a liver-humanized mouse (PXB-cells) as a model in vitro system for the prediction of the in vivo metabolism of new drugs of abuse was evaluated.

Methods: For the drug metabolism study, fentanyl, a powerful synthetic opioid, and acetylfentanyl, an -acetyl analog of fentanyl, were selected as model drugs. PXB-cells were cultured with the drug for 24-48 h and then the media were collected and analyzed by liquid chromatography/mass spectrometry after deproteinization with acetonitrile.

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Background: Segmental hair analysis can be useful for estimating the time of drug intake. However, this estimation is currently only accurate to within several months. We previously conducted microsegmental analysis of a strand of hair to visualize drug distribution at a spatial resolution of 0.

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Since fragments of concrete can be evidence of crime, a determination of whether or not they come from the same origin is required. The authors focused on nitric acid-soluble components in the fragments of concrete. As a result of qualitative analysis with ICP-MS, it was confirmed that elements such as Cu, Zn, Rb, Sr, Zr, Ba, La, Ce, Nd, and Pb were contained in the fragments.

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Body fluid (BF) identification is a critical part of a criminal investigation because of its ability to suggest how the crime was committed and to provide reliable origins of DNA. In contrast to current methods using serological and biochemical techniques, vibrational spectroscopic approaches provide alternative advantages for forensic BF identification, such as non-destructivity and versatility for various BF types and analytical interests. However, unexplored issues remain for its practical application to forensics; for example, a specific BF needs to be discriminated from all other suspicious materials as well as other BFs, and the method should be applicable even to aged BF samples.

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The source of small amounts of touch DNA, which is transferred from the skin to an object when it is handled or touched, could be an issue in the forensic analysis of criminal cases. Here, we performed an extended evaluation of skin- or sweat-characteristic mRNAs to investigate their usability to infer whether an object has been handled or touched by someone. First, we compared the expression levels of candidate genes between skin swabs and other body fluids by quantitative RT-PCR analysis.

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Sleeping aids are often abused in the commission of drug-facilitated crimes. Generally, there is little evidence that a victim ingested a spiked drink unknowingly because the unconscious victim cannot report the situation to the police immediately after the crime occurred. Although conventional segmental hair analysis can estimate the number of months since a targeted drug was ingested, this analysis cannot determine the specific day of ingestion.

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Recent studies have shown that a memorized item in the Concealed Information Test elicits a frontal negative slow wave (500-1000 ms) of the event-related potential, the cortical source of which involves the right prefrontal cortex. To examine whether this negative slow wave reflects a process that is specific to concealment rather than a more general cognitive control process, we compared the event-related potentials of 24 participants in four conditions involving the presence or absence of memory and the intention to conceal. Results showed that right prefrontal activation during the frontal negative slow wave (estimated by Standardized Low Resolution Brain Electromagnetic Tomography) was only observed when participants attempted to conceal the memorized item, but not when they were motivated to reveal it or had no intention to conceal.

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In recent years, analysis of cannabis DNA has been increasingly used in forensic drug tests. However, in the case of cannabis resin, a processed marijuana product, complicated procedures are required for the extraction of clean DNA, as the presence of various impurities inhibits PCR amplification. Therefore, in this study, we attempted to identify the factors that would allow quick and simple DNA extraction from cannabis resin with a commercially available kit.

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To evaluate the capability of human-induced pluripotent stem cell-derived hepatocytes (h-iPS-HEP) in drug metabolism, the profiles of the metabolites of fentanyl, a powerful synthetic opioid, and acetylfentanyl, an N-acetyl analog of fentanyl, in the cells were determined and analyzed. Commercially available h-iPS-HEP were incubated with fentanyl or acetylfentanyl for 24 or 48 h. After enzymatic hydrolysis, the medium was deproteinized with acetonitrile, then analyzed by LC/MS.

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The pressure- and temperature-sensitive paint (PSP/TSP) technique, for steady-state and unsteady-state measurements, is becoming widespread. However, unsteady quantitative measurement is still difficult because non-uniform distribution of the probes over a test model may cause errors in the results. We focus on the dipping method that applies two luminophores into a binding material to improve sensitivity uniformity over a model surface.

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We developed a dual plasma desorption/ionization system using two plasmas for the semi-invasive analysis of compounds on heat-sensitive substrates such as skin. The first plasma was used for the desorption of the surface compounds, whereas the second was used for the ionization of the desorbed compounds. Using the two plasmas, each process can be optimized individually.

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Methods to quickly purify methamphetamine hydrochloride from the cutting agent dimethyl sulfone for subsequent identification of confiscated crystalline samples using infrared absorption spectroscopy were compared and evaluated. Although sequential solvation and reprecipitation methods were simple, spectral contamination from dimethyl sulfone was inevitable and might affect the interpretation of the spectra. In addition, methamphetamine hydrochloride and dimethyl sulfone could form a solid solution because of solvation of both crystals into a single solution layer.

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Practical evaluation of an RNA-based saliva identification method.

Sci Justice

November 2017

Department of Forensic Dentistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo 113-8510, Japan.

Identifying saliva in samples found at crime scenes is important to clarify the tissue origin of DNA obtained for identification of individuals. Recently, a novel messenger RNA-based approach using two saliva-specific markers, Statherin (STATH) and Histatin 3 (HTN3), has been reported. This method can identify saliva more specifically than conventional amylase-based methods.

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The concealed information test (CIT) is a psychophysiological memory detection technique for examining whether an examinee recognizes crime-relevant information. In current statistical analysis practice, the autonomic responses are usually transformed into Z scores within individuals to remove inter- and intra-individual variability. However, this conventional procedure leads to overestimation of the effect size, specifically the standardized mean difference of the autonomic responses between the crime-relevant information and the crime-irrelevant information.

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By combining a bolometer detector with an imaging-type interferometer, an inexpensive, easy-to-handle wide-field mid-infrared hyperspectral imaging apparatus was produced. We measured the distributions of four types of thin adhesive layers on an aluminium plate and analysed the results using correlation coefficients to visualise the distribution of various adhesives that cannot be discerned by the naked eye or conventional methods such as visible/near-infrared spectroscopic/fluorescent photography. The measurement wavelength range, obtained spectrum's wavenumber resolution, and measurement time was 8-14 μm, about 9 cm, and about 30 s, respectively.

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The time-resolved luminescence spectra and the lifetimes of eighteen black writing inks were measured to differentiate pen ink on altered documents. The spectra and lifetimes depended on the samples. About half of the samples only exhibited short-lived luminescence components on the nanosecond time scale.

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Zopiclone and its (S)-enantiomer (eszopiclone) are commonly prescribed for insomnia. Despite the high demand for enantioselective differentiation, the chiral analysis of zopiclone in hair has not been reported. In this study, a method for the enantioselective quantification of zopiclone in human hair was developed.

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Often in criminal investigations, discrimination of types of body fluid evidence is crucially important to ascertain how a crime was committed. Compared to current methods using biochemical techniques, vibrational spectroscopic approaches can provide versatile applicability to identify various body fluid types without sample invasion. However, their applicability is limited to pure body fluid samples because important signals from body fluids incorporated in a substrate are affected strongly by interference from substrate signals.

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Segmental hair analysis is used to estimate the time of drug intake at monthly precision in drug-related crimes. Previously, we advanced this analytical method to specify the day of drug intake by cutting a strand of hair into 0.4-mm segments, which correspond to daily hair growth.

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Detection of aged fingerprints is difficult because they can degrade over time with exposure to light, moisture, and temperature. In this study, aging fingerprints were visualized by time-resolved spectroscopy with an ultraviolet-pulsed laser. Fingerprints were prepared on glass slides and paper and then stored under three lighting conditions and two humidity conditions for up to a year.

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The cis and trans isomers of 3-methylfentanyl and its three analogs were chemically synthesized, and these compounds were characterized and differentiated by gas chromatography/mass spectrometry (GC/MS), liquid chromatography/mass spectrometry (LC/MS), and nuclear magnetic resonance (NMR) spectroscopy. The cis and trans isomers of the 3-methylfentanyl analogs were completely separated by GC/MS. Although the high temperature of the GC injection port caused thermal degradation of β-hydroxy-3-methylfentanyl, the degradation was completely suppressed by trimethylsilyl derivatization.

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The first aim of this study was to investigate predictors of future traffic crash involvement, taking into account bias in the handling of data for former drivers. The second aim was to compare characteristics of former drivers and crash-involved drivers in order to gain an understanding of appropriate driving cessation among older drivers. In all, 154 drivers aged 70 years or older participated in the baseline interview and the follow-up survey conducted two years later.

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A field-portable gas chromatography-mass spectrometry (GC-MS) system (Hapsite ER) was evaluated for the detection of nonvolatile V-type nerve agents (VX and Russian VX (RVX)) in the vapor phase. The Hapsite ER system consists of a Tri-Bed concentrator gas sampler, a nonpolar low thermal-mass capillary GC column and a hydrophobic membrane-interfaced electron ionization quadrupole mass spectrometer evacuated by a non-evaporative getter pump. The GC-MS system was attached to a VX-G fluoridating conversion tube containing silver nitrate and potassium fluoride.

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A target analysis method for the sensitive and discriminative determination of the nerve agent hydrolysis products alkyl methylphosphonic acids as their tert-butyldimethylsilyl (TBDMS) derivatives was developed using a combination of selectable one- and two-dimensional (D/D) GC-MS, and applied to the analysis of samples with significant interfering matrices. After sample drying, the alkylmethylphosphonic acids and methylphosphonic acid (MPA) were converted to TBDMS derivatives by addition of N-methyl-N-(tert-butyldimethylsilyl)trifluoroacetamide with heating, and subjected to D/D GC-MS. The apparatus consisted of an initial low thermal mass DB-5 column and a second DB-17 column together with an electron ionization quadrupole mass spectrometer, offering simple and flexible switching between one- and two-dimensional GC-MS analysis in a single GC-MS system.

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Food poisoning is frequently caused by the accidental ingestion of toxic plants that possess strong morphological similarities to edible plants. False helleborine (Veratrum album) is one of the most common plants involved in such accidents. In cases of poisoning by toxic plants, rapid and accurate identification, usually based on the morphological or chemical analysis of plant parts, is required for appropriate medical treatment or forensic investigation.

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