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981.
Toluene, an abused substance in Japan, is a neurotoxic chemical that has been shown to have neurobehavioral and electrophysiological effects. In previous work, both acute and chronic effects of toluene on cells have been studied extensively. However, although glial cells are thought to play an important role in the survival of neurons in the brain, the effect of toluene on glial cell function has not yet been characterized. To elucidate this, the effect of toluene inhalation on astrocytes in rat brain was examined. Toluene exposure (1500 ppm for 4 h on 4-10 days) augmented glial fibrillary acidic protein (GFAP) immunoreactivity, particularly in the hippocampus and cerebellum. Quantitative analysis showed that toluene inhalation markedly enhanced GFAP expression in the hippocampus and cerebellum. In both regions, proliferating cell nuclear antigen (PCNA) showed no obvious changes, but glutamine synthetase (GS)-immunoreactive cells were markedly increased by toluene exposure. Thus, the elevation of GFAP expression was induced by astrocyte activation rather than by cell proliferation. If toluene exposure activates astrocytes, astrocytes may play a role in the neurophysiological changes observed in toluene intoxication. A neurotrophic factor, basic fibroblast growth factor (b-FGF) was observed immunohistochemically in the capillary vessel walls in the hippocampus and the cerebellum of toluene-intoxicated rats. Basic-FGF may have induced GFAP expression both in the hippocampus and the cerebellum. So, other neurotrophic factors may affect the difference of GFAP elevation between the hippocampus and the cerebellum. These differences may relate to neurobehavioral function of each brain part after toluene exposure.  相似文献   
982.
Several lectins were used to study the localization of glycoconjugates in brain of elderly people and patients with Alzheimer type dementia (ATD) and Down's syndrome (DS). Five kinds of degenerated or deposited materials stained clearly by lectins specific to GalNAC, Gal, Fuc, and/or Man were recognized much in ATD and DS, less in elderly peoples, in addition to the binding of the lectins to neurons. (i) Round shape deposits called corpora amylacea (CA) which consisted of various sizes of round material, existed mainly on the surface of cerebral cortex and some in white matter of the brain. They were colored by Alcian blue (AB), Aldehyde fucsin (AF) and periodic acid shiff (PAS) and weakly by Hematoxylin (H), but not by Eosin (B). They showed clear reactivity with lectins specific to GalNAC, Gal, Fuc and Gal-GalNAC. (ii) Amorphous and variform amyloid deposits existed around blood vessels in the white matter were stained by thioflavin and lectins specific to GalNAC, Gal and Fuc, but not with Man specific lectins and PAS, AB, AF and HE. (iii) Another kind of amyloid deposits which showed a similar characteristic to the previous one and were recognized mainly in white matter and independent blood vessels. These deposits were stained by thioflavin but not by PAS, AB, AF and HE and showed good reactivity with lectins specific to GalNAC, Gal, Fuc, Gal-GalNAC, Gal-GIcNAc and Man. The reactivity with lectins specific to Gal, Fuc, and Man was seen in senile plaques (iv) and neurofibrillary tangles (v). Although at present we are unable to explain the origin of these deposits, it is clear from this study that the glycoconjugates form an integral part of the degeneration in the brain. The lectin staining with GS-I is useful in the forensic pathology to diagnose brain disorders at postmortem examination, since these lectin were able to detect five types of degeneration changes and/or deposits.  相似文献   
983.
By means of the new method of Streifenlichttopometrie (SLT) it is possible to record the complete body surface of casualties in a practically photorealistic fashion, i.e. three-dimensionally and in colour. In comparison with the classic method of Photogrammetry Streifenlichttopometrie (SLT) is remarkably faster (10,000 points/s instead of 1 point/s) and in addition the colour of every point measured upon the corpse's surface is instantly recorded. Taking into consideration the resolution required and the qualities of the camera system the body surface is recorded in 'patches', i.e., areas of a defined extension (in the present case 500 mmx500 mmx200 mm) which are marked with a body fixed reference frame to grant the exact matching of the data after the recording process. Length, perimeter, square and volume of the body segments and injuries can be determined. Furthermore the natural colour of the wounds can be used for an immediate classification according to the intensity of the impact forces. In addition the 3-D coordinates of the body surface including the wounds can be transferred into an animated computer simulation for the reconstruction of the traumatic events.  相似文献   
984.
Fentanyl is a very strong opioid with analgesic properties that are approximately 80 times stronger than those of morphine and therefore is used in major surgery and treatment of pain in tumor patients. Cases of fentanyl abuse by intravenous injection, inhalation, oral or nasal application have been reported especially in the USA. Therapeutic levels of fentanyl are as low as 1 ng/ml of serum and therefore a screening test must have a detection limit below that concentration. Recently three non-radioactive enzyme immunoassays (EIAs) have become commercially available from COZART, STC and DIAGNOSTIX, all of them supplied by MAHSAN Diagnostika for evaluation with serum samples from forensic and clinical cases. A calibration curve is obtained with samples that contain 0, 0.1, 0.5, 1 and 5 ng fentanyl per ml of negative serum. The calibration curve of COZART is especially in the low range, steeper than those of STC and DIAGNOSTIX. The cut-off for all these EIAs, however, can be set at 0.5 ng/ml. After the administration of therapeutic doses, fentanyl concentrations were between 3 and more than 5 ng/ml as determined with the EIAs. The presence of the typical drugs of abuse, e.g. heroin, methadone, cocaine, cannabinoids and amphetamines including the derivatives of methylenedioxyamphetamine, don't generate false-positive results. No cross-reactivity was also observed at toxic levels of benzodiazepines and paracetamol and therapeutic levels of barbiturates, phenothiazines, antidepressants and analgesics. The EIAs tested so far appear to be suitable for the detection of fentanyl at therapeutic levels. False-positive results or cross-reactivity towards other compounds have not been observed.  相似文献   
985.
Benzodiazepines are one of the most widely prescribed drugs for the treatment of a wide spectrum of clinical disorders. They are used as anticonvulsants, anxiolytics, hypnotics or muscle relaxants with different duration of action. In this paper, a simple and sensitive method for the determination of benzodiazepines in whole blood using solid-phase extraction and gas chromatography/mass spectrometry (GC/MS) is described. The drugs spiked in whole blood were extracted with an Oasis HLB solid-phase extraction cartridge (Waters), which contains a copolymer designed to have a hydrophilic-lipophilic balance. GC/MS analysis was performed using a Shimadzu QP-5000 equipped with a BPX5 capillary column (15 mx0.32 mm I.D., film thickness 0.25 microm, SGE). Nineteen benzodiazepines and two thienodiazepines were well separated from each other on their SIM chromatograms and also on the TIC with the exception of oxazolam to cloxazolam separation. The blank extract from whole blood gave no peaks that interfered with all benzodiazepines and thienodiazepines on the chromatogram. The calibration curves for selected benzodiazepines with fludiazepam as an internal standard showed excellent linearity over the concentration range 5-500 ng/ml blood with a correlation coefficients of >0.995. The detection limits ranged from 0.2 to 20 ng/ml blood. The method is simple and sensitive for the determination of benzodiazepines in whole blood and seems to be useful in the practice of forensic science.  相似文献   
986.
A fast method using liquid-liquid extraction and HPLC/tandem-mass spectrometry (LC/MS/MS) was developed for the simultaneous detection of 11-Nor-Delta(9)-tetrahydrocannabinol-9-carboxylic acid beta-glucuronide (THC-COOH-glucuronide) and 11-Nor-Delta(9)-tetrahydrocannabinol-9-carboxylic acid (THC-COOH) in urine samples. This highly specific method, which combines chromatographic separation and MS/MS analysis, can be used for the confirmation of positive immunoassay results even without hydrolysis of the sample or derivatisation of extracts. Liquid-liquid extraction was optimised: with ethylacetate/diethylether (1:1, v/v) THC-COOH-glucuronide and THC-COOH could be extracted in one step. Molecular ions of the glucuronide (MH(+), m/z 521) and THC-COOH (MH(+), m/z 345) were generated using a PE/SCIEX turboionspray source in positive ionisation mode; specific fragmentation was performed in the collision cell of an API 365 triple-quadrupole mass spectrometer and yielded major fragments at m/z 345 (for THC-COOH-glucuronide) and m/z 327 as well as m/z 299 for both cannabinoids. Chromatographic separation was performed using a reversed-phase C8 column and gradient elution with 0.1% formic acid/1 mM ammonium formate and acetonitrile/0.1% formic acid. Retention times were 22.2 min for the glucuronide and 26.8 min for THC-COOH. After enzymatic hydrolysis of urine samples with beta-glucuronidase/arylsulfatase (37 degrees C, 5 h), THC-COOH-glucuronide was no longer detectable by LC/MS/MS in urine samples. However, the THC-COOH concentration was increased. For quantitation of THC-COOH, THC-COOH-D(3) was added to the urine samples as internal standard prior to analysis. From the difference of THC-COOH in the native urine and urine after enzymatic hydrolysis, molar concentration ratios of THC-COOH-glucuronide/THC-COOH in urine samples of cannabis users were determined and found to be between 1.3 and 4.5.  相似文献   
987.
To outline the recent features of methamphetamine-related fatalities from the medico-legal point of view, a retrospective investigation of forensic autopsy cases involving methamphetamine during a 5-year period (1994-1998) in the southern half of Osaka city and surrounding areas (about 1.57 million population) was undertaken. Among 646 autopsy cases, methamphetamine was detected in 15 victims (nine males, six females; 16-71 years of age; most frequently in males in their thirties). Primary scenes of fatal events were concentrated in the middle of the city. About half of them were transferred from emergency medical centers (survival time, up to 30 h). The cause and manner of death were: methamphetamine poisoning (n=4), homicide (n=4), accidental falls and aspiration from drug abuse (n=4), fire death (n=1), myocardial infarction (n=1), and cerebral hemorrhage (n=1) under drug influence. Usually injection scars and fresh puncture sites were found. Blood methamphetamine concentrations were 2.29-17.05 micromol/dl in the fatal poisoning, 0. 44-3.80 micromol/dl in deaths from other extrinsic causes (trauma), and 1.35-2.17 micromol/dl in cardio- and cerebrovascular strokes. Common complications were cardiomyopathy, cerebral perivasculitis and liver cirrhosis/interstitial hepatitis. Fatal and nonfatal methamphetamine poisonings are separately dealt with by the administrative medical examiner's office and in emergency medical centers. Tightly cooperative approaches of clinical and medico-legal experts are required for the effective social and medical management of drug abuse.  相似文献   
988.
A total of 36 ancient human remains from 12 individuals (three tooth/bone samples each) and one sample each of three individuals from the newest time was typed in a blind study using the amelogenin sex test. Prior to this molecular sex determination the sex of the individual was determined morphologically. The success rate of the amelogenin amplifications was >90%. For every individual an unambiguous molecular sex typing result was obtained. Furthermore, the morphological and molecular sex determinations were in accordance with each other, giving evidence for the authenticity and ancient origin of the polymerase chain reaction (PCR) amplifications.  相似文献   
989.
DNA typing is often used to determine identity from human remains. The environment to which the material has been exposed, however, is crucial for the success of the investigation. Damp conditions in particular can cause a rapid degradation of DNA, even in bone and teeth, and thus reduce the chances of successful typing. Here, we present the results of investigations performed on four skulls that had been lying in a damp environment for periods ranging from almost 1 year to about 45 years. In none of these cases was DNA typing successful on bone or, where present, on teeth. Where remnants of brain tissue were used, however, complete STR typing was possible in one case, partial STR typing in another, and mtDNA sequencing could be carried out in three cases. These findings suggest that brain tissue is relatively resistant to putrefaction in damp environments and, unlike bone, appears to exhibit a certain degree of protection against DNA degradation.  相似文献   
990.
Papillary fibroelastoma is a rare benign tumor, occasionally causing angina or sudden death. We report an autopsy case of an aortic valve papillary fibroelastoma with coronary artery embolism. The patient was a 68-year-old Japanese man who had collapsed suddenly in his house. He was a heavy drinker and had a history of liver disease but no notable cardiac event. The autopsy revealed extensive transmural infarction of the inferior wall of the left and right cardiac ventricles. The distal portion of the right coronary artery (segment 4, NYHA) was completely occluded by tumor emboli of the fibroelastoma. At the site of closure of the aortic non-coronary cusp, there was a typical papillary fibroelastoma, which was considered to have originated the coronary embolization.  相似文献   
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