Biomedical subjects

R Matoba

Publications and source records attributed to R Matoba.

At least 37 records · Page 2Linked to original sources

PubMed2000

Analysis of citrulline in rat brain tissue after perfusion with haloperidol by liquid chromatography-mass spectrometry.

We have investigated the potential of high-performance liquid chromatography (HPLC) coupled to mass spectrometry (MS) to determine enrichments of citrulline as a marker for in vivo nitric oxide (NO) production in brain tissue. The analysis of citrulline as the butyl ester derivative was evaluated using two types of ionization: electron spray ionization (ESI) and atmospheric pressure chemical ionization (APCI). APCI-MS appeared to be more suitable for determination of citrulline than ESI-MS, because the ion intensity of the protonated molecule ion [M+H]+, m/z 232, of citrulline in the former was about twelve times higher than in the latter. The chromatography was carried out on a reversed C8 column with the mobile phase consisting of 15% acetonitrile: 85% H2O: 0.2% acetic acid (v/v). The calibration curve had good linearity within the concentration range investigated (5 ng to 500 ng/ml). The limit of determination was estimated to be ca. 1 ng/ml of standard solution. The method was applied to the analysis of citrulline in the brain dialysate obtained from rat after perfusion of the striatum with haloperidol (HP, 0.1 mM). It is concluded that APCI-MS in combination with HPLC can be successfully applied to determination of citrulline in brain tissue, thus providing a useful tool for assessment of in vivo NO production.

Animals↗

PubMed2000

Gene expression in mouse cerebellum during its development.

Genes expressed during the cerebellar development of the mouse were identified in 3'-directed cDNA libraries prepared from the postnatal day 4, day 12, and week 6 cerebellar tissues. Among about 5500 clones selected randomly from each library, there were approximately 3500 distinct species. A total of 7728 species were identified in the three libraries, 1346 of which were known genes in the GenBank, 3041 EST-matching genes, and 3341 new genes. Relative expression levels at the three postnatal stages were quantitated by adapter-tagged competitive PCR for 130 known genes that appeared six times or more in one of the libraries. Genes for ribosomal proteins and some cytoskeletal and nuclear proteins were abundantly expressed at the early stage, coincidently with extensive proliferation of granule cells as the major cerebellar component. Genes related to brain functions, including those for mitochondrial activities and some ion channel systems, were more active at a later stage when the majority of granule cells were engaged in axon extension and synapse formation or the cerebellum had reached maturity. Compared to these stage-specifically expressed genes, genes for transcriptional regulation, signal transduction, protein modification, and basic cellular functions, in general, were not abundantly expressed at any stage of development.

Animals↗

PubMed2000

Development of haemoglobin subtypes and extramedullary haematopoiesis in young rats. Effects of hypercapnic and hypoxic environment.

The influence of repeated hypoxia on the development of haemoglobin (Hb) subtypes and on extramedullary haematopoiesis (EMH) was investigated in young Wistar rats of different ages. The rats were exposed to hypercapnic/hypoxic and to "simple" hypoxic conditions. The results obtained were compared to those of an untreated age-matched control group. Different globin chains were measured using HPLC and time-of-flight (TOF) mass analysis. The number of EMH cells was evaluated by cell counting. By determining the proportions of alpha- and beta-chains, fetal, neonatal and mature types of globin chain composition could be differentiated. The beta-2 chain levels were significantly higher in hypercapnic/hypoxic environments than in the controls and simple hypoxic environments. The numbers of EMH cells in the two groups subjected to hypercapnia/hypoxia decreased significantly more slowly compared to the controls and simple hypoxia groups. Therefore, the development of Hb subtypes and the EMH activity in rats were influenced by both repeated hypercapnia and hypoxia.

Animals↗

PubMed2000

Methamphetamine induces an increase in cell size and reorganization of myofibrils in cultured adult rat cardiomyocytes.

To investigate the direct effects of methamphetamine (MAP) on cardiac lesions seen in MAP abusers, isolated adult rat ventricular cardiomyocytes (ARCs) were exposed to MAP (0.05-1.0 mM) in medium 199 containing 10% fetal calf serum. Isolated ARCs attached to laminin-coated substrata and began to spread into polygonal shapes with pseudopodia at day 6 in normal culture. However, the cell attachment and spreading were inhibited by exposure to MAP (0.5 and 1.0 mM) for the first 7 days in culture. On the other hand, exposure to MAP (0.05 and 0.1 mM) for 7 days after a 6-day period of normal culture, led to a larger cross surface area of cells with more abundant actin bundles compared to control cells (p < 0.05). This development of spreading area resembled that of norepinephrine-treated ARCs. In addition, immunoreactive atrial natriuretic peptide (ANP) granules developed and accumulated around the nuclear region of ARCs exposed to MAP and the number of ANP positive cells tended to increase in a dose-dependent manner. These results suggest that chronic exposure to a high concentration of MAP may directly inhibit development of ARCs in culture and that a continuous exposure to a low concentration of MAP may facilitate the development of cellular hypertrophy. Therefore, hypertrophied cardiomyocytes in MAP abusers may be provoked by multifactorial incidents of direct and indirect actions of MAP.

Animals↗

PubMed2000

An autopsy case of salt poisoning from drinking a large quantity of shoyu (Japanese soy sauce).

We report herein a suicide case of salt poisoning from drinking a large quantity of shoyu (Japanese soy sauce). The deceased was a 60-year-old housewife who was found dead in her bedroom by her husband. An empty 1,000 ml bottle of shoyu, which had been purchased on the day before death, was discovered in the kitchen. Macroscopically, the alimentary tract contained a yellowish-brown liquid-like material with the strong smell of shoyu, and slight lung and brain edema were noted. The 1,000 ml bottle of shoyu contained approximately 160 g of salt. Therefore, the cause of death was determined to have been salt poisoning from drinking a large quantity of shoyu.

Journal Article↗

PubMed2000

Correlation between gene functions and developmental expression patterns in the mouse cerebellum.

Quantitative changes of 419 gene transcripts during postnatal mouse cerebellar development were accurately determined with a novel polymerase chain reaction (PCR)-based technique. About 70% of the genes showed differences in expression levels, and the magnitude of difference was relatively small. By hierarchic cluster analysis of developmental expression patterns, the genes were categorized into 19 clusters, which were subsequently assembled into four major groups: group 1, with elevation of gene expression throughout the time course; group 2, with relatively unchanged levels; group 3, with transiently high expression at approximately 12 days; and group 4, with highest expression at approximately 4 days. Genes related to brain functions were segregated into several clusters of group 1 and group 3: the same clusters in which cerebellum-specific genes were also segregated. Genes for protein synthesis belonged to group 4. Genes with housekeeping functions belonged to group 2. Western blotting analysis of representative protein products of each group revealed correlation with the mRNA level for those belonging to group 1 and group 4, but not necessarily in the other groups. The close correlation of algorithmically categorized temporal expression patterns of genes with their functions will be useful for estimating the functions of thousands of novel genes.

Animals↗

PubMed2000

BodyMap: a collection of 3' ESTs for analysis of human gene expression information.

BodyMap is a collection of site-directed 3' expressed sequence tags (ESTs) (gene signatures, GSs) that contains the transcript compositions of various human tissues and was the first systematic effort to acquire gene expression data. For the construction of BodyMap, cDNA libraries were made, preserving abundance information and histologic resolutions of tissue mRNAs. By sequencing 164,000 randomly selected clones, 88,587 GSs that represent chromosomally coded transcripts have been collected from 51 human organs and tissues. They were clustered into 18,722 independent 3' termini from transcripts, and more than 3000 of these were not found among ESTs assembled in UniGene (Build 75). Assessment of the prevalence of polyadenylation signals and comparison with GenBank cDNAs indicated that there was no significant contamination by internally primed cDNAs or genomic fragments but that there was a relatively high incidence (12%) of alternative polyadenylation sites. We evaluated the sensitivity and resolution of expression information in BodyMap by in silico Northern hybridization and selection of tissue-specific gene probes. BodyMap is a unique resource for estimation of the absolute abundance of transcripts and selection of gene probes for efficient hybridization-based gene expression profiling.

3' Untranslated Regions↗

PubMed2000

A novel mutation of the KAL1 gene in monozygotic twins with Kallmann syndrome.

OBJECTIVE: Kallmann syndrome is defined by the association of hypogonadotropic hypogonadism and anosmia. The KAL1 gene is responsible for the X-linked form of Kallmann syndrome. In this study we describe monozygotic twins with Kallmann syndrome due to the same mutation in the KAL1 gene. DESIGN: We studied male monozygotic twins with Kallmann syndrome. METHODS: We analyzed the KAL1 gene using the PCR-direct sequencing method. The twins' mother was examined for the identified mutation. RESULTS: We identified a 14 bp deletion from codon 419 in exon 9 (Pro419del14) in both KAL1 genes of the twins. This was a novel mutation in the KAL1 gene and was responsible for Kallmann syndrome. As Pro419del14 was not detected in the mother of the twins, Pro419del14 was a germline mutation originating from them. These monozygotic twins showed different LH and FSH responses to LH-RH stimulation and different phenotypes such as complications, physiques and psychiatric characters. CONCLUSIONS: We report an identical KAL1 gene mutation in the monozygotic twins with Kallmann syndrome. As these monozygotic twins showed different phenotypes in some respects, we suggest that factors other than mutations in the KAL1gene affect the symptomatic features of Kallmann syndrome.

Adult↗

PubMed1999

An unusual autopsy case of a victim stabbed during sadomasochistic prostitution.

A 29-year-old male who lived alone was found dead with his back leaning against the wall of his room. He had been stabbed in his abdomen with a survival-type knife. The victim's mouth was plugged with a pink-colored glove and was sealed with packing tape. His wrists were tightly tied behind his back with the same type of packing tape. The cause of death was diagnosed as hemorrhage from the right common iliac artery and vein. Due to the strange circumstances of the crime scene, the police initially considered the possibility of homicide by a group of assassins. Two months later, the police arrested a male suspect who was a member of a vice racketeer. The victim was characterized as a masochist and bisexual. He often hired the male suspect to perform sadomasochistic activities. On the day of the crime, the victim prepared a survival-type knife and packing tape himself to experience fear and pain more strongly. The victim hoped to use the knife to increase sexual excitement. In this case of sadomasochistic prostitution leading to death, the legal issues of homicide for money, malicious request of injury by the victim and accidental death were involved.

Journal Article↗

PubMed1999

Simultaneous detection of multiple STR loci on sex chromosomes for forensic testing of sex and identity.

The forensic usefulness of X and Y chromosomal STR loci has recently been demonstrated. One quadruplex-PCR, using 2 X- and 2 Y-STRs (STRX1/HPRTB and DYS390/ DYS393), and 2 duplex-PCRs, each using an X- and a Y-STR (ARA/DYS390 and ARA/DYS393), and detection of PCR products by using an automated DNA sequencer are reported herein. This approach allows us to determine not only the sex of the donor of a sample, but also the X- and/or Y-STR genotypes of the sample. A male biological specimen yields 4 amplified products in quadruplex-PCR and 2 amplified fragments in duplex-PCRs, whereas a female biological specimen yields only 2 amplified fragments of X-STR in quadruplex-PCR and one fragment, also of X-STR, in duplex-PCRs. Our study thus provides useful information for many activities in forensic practice, such as identity testing, paternity testing, especially of deficiency cases, compilation of population data, and sex determination of a biological sample from a single PCR.

Alleles↗

PubMed1998

[A case of identification of two persons from heavily burned teeth by age estimation].

A man murdered his two daughters, one five years and two months old and one seven months old. He placed them into a 750 degrees C aluminum liquefying furnace. Teeth and many fragments of the severely burned bones were recovered. However, at first, the bone fragments did not offer proof that two children were put into the furnace. The age estimation of the teeth burned in liquefied aluminum was carried out based on the maturity of the teeth and the degree of absorption of deciduous teeth roots. As a result from the admixture of permanent teeth and deciduous teeth, we presumed them to be derived from more than one person.

Age Determination by Teeth↗

PubMed1997

Use of high-performance liquid chromatography as an extraction procedure for analysis of triazolam in decomposed human muscle by gas chromatography-mass spectrometry.

A reliable and sensitive method for the determination of triazolam in human muscle using gas chromatography-mass spectrometry (GC-MS) is described. The drug was extracted from decomposed human muscle using three-step liquid-liquid extraction and HPLC which was performed isocratically on a conventional ODS column with a mobile phase of 0.01 M phosphate buffer (pH 6.5)-acetonitrile (7:3). Estazolam was used as an internal standard. GC-MS analysis was performed on a DB-5 capillary column. Excellent linearity was obtained over the concentration range 1-200 ng/g. The lower limit of detection was approximately 0.5 ng/g. Forensic application of the present method was also described.

Chromatography, High Pressure Liquid↗

PubMed1997

Eighteen novel human genes regionally mapped on chromosome 11.

Expression sequence tags (EST) obtained by sequencing a randomly primed cDNA library and gene signatures (GS) obtained by sequencing a 3'-directed cDNA library can identify genes that are active in the source cells. Eight ESTs and ten GSs which represent novel human genes, except for one GS, and which have been assigned to human chromosome 11 were used to select cosmids from a chromosome 11-specific cosmid library. These cosmids were regionally mapped using the fluorescence in situ hybridization technique.

Animals↗

PubMed1997

Sensitive detection of human globin chains by microbore high-performance liquid chromatography and its forensic application.

This paper describes a simple and sensitive high-performance liquid chromatographic (HPLC) method for the detection of human globin chains in blood and bloodstains. The method involves direct injection of the filtered samples of dilute hemolysates or bloodstain extracts onto a microbore C4 reversed-phase column (2.1 mm I.D.) with UV detection at 220 nm. Microbore HPLC offers a significant improvement in sensitivity with little loss of the resolution of globin chains and only small variations in the determination of gamma chain composition. The detection limit of hemoglobin (Hb) was 0.1 microgram, which is equivalent to about 1 nl of fresh whole blood. Umbilical cord blood could be differentiated from adult blood in stains that were up to twenty weeks old, by the presence of gamma globin chains. The present method will be useful for detection of abnormal Hbs and for the determination of gamma chain composition in clinical laboratories, as well as in the practice of forensic science for the analysis of minute amounts of blood and bloodstains.

Blood Stains↗

PubMed1996

Detection of toluene in an adipoceratous body.

A 24-year-old male was found dead in a car left in a river for about 3 months. The cadaver was almost adipoceratous and autopsy findings revealed that there were neither remarkable injuries nor lethal diseases. Toluene, ethanol, 1-propanol, 2-propanol, 1-butanol, dimethyl sulfide, dimethyl disulfide, isovaleraldehyde and n-butyl n-butyrate were detected in the specimens collected at the autopsy by head space gas chromatography/mass spectrometry (GC/MS). The toluene concentrations (micrograms/g) were 31.0 in brain, 10.6 in liver, 5.4 in kidney, 15.0 in skeletal muscle and 187.1 in adipose tissue. The presence of diatom in lung, liver and kidney suggested that death was caused by drowning. So far as we know, this is the first report of detection of toluene in an adipoceratous body.

Adipose Tissue↗

PubMed1996

Induction of apoptotic cell death in rat thymus and spleen after a bolus injection of methamphetamine.

We examined whether methamphetamine (MAP) induced apoptotic cell death in vivo. Male Wistar rats were injected intraperitoneally with 25 mg MAP/Kg body weight and were sacrifice at 4, 8 and 24 h. As early as 4 h after a single dose of MAP, DNA ladder bands representing DNA fragmentation into multiples of the internucleosomal DNA length of about 180 by were observed by gel electrophoresis in thymic and splenic DNA. DNA from control rats injected with 1 ml physiological saline/Kg body weight showed no ladder band patterns. The proportion of fragmented DNA from the thymus increased in a time-dependent manner up to 8 h and faint ladder band patterns were observed at 24 h, indicating that cell death via apoptosis occurred at an early stage and then apoptotic bodies were scavenged. DNA fragmentation in the thymus and spleen induced with MAP was also confirmed by the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) method in situ. In control thymus samples, stained cells were numerous in the cortex but sparse in the medulla. At the boundary area between the cortex and medulla, stained cells were seen as a layer. In the MAP-treated rats, stained cells were increased and dispersed equally in the cortex and medulla. In control spleen samples, stained cells were numerous in all areas excluding the germinal centers. Cells at the germinal centers were stained intensively in MAP-treated rat spleen. Light microscopical analyses allowed us to identify lymphocytes during the course of apoptotic cell death. Electron microscopic studies showed morphological landmarks for the process of cellular apoptosis in both organs e.g. lymphocytes with chromatin condensed into crescents at the periphery of the nuclei and apoptotic bodies. These result indicate that MAP induced cell death of the thymic and splenic lymphocytes via apoptosis.

Animals↗

PubMed1996

Cardiac muscle lesions associated with chronic administration of methamphetamine in rats.

Cardiovascular complications associated with methamphetamine abuse have increasingly been reported. However, chronic cardiotoxicity of methamphetamine is not experimentally well documented. In this study, methamphetamine (1 mg/kg/day) was subcutaneously injected into 5-week-old male Wistar Kyoto rats (n = 30). Age- and sex-matched Wistar Kyoto rats served as controls (n = 30). After 14 and 56 days, hearts were examined by light and electron microscopy. Foci of myocytic degeneration and necrosis appeared in the sub-endocardial areas on day 14 of methamphetamine exposure. Myocytic degeneration and necrosis became more extensive on day 56. At this stage, myocytolysis, contraction bands, atrophied myocytes, and spotty fibrosis were patchily distributed throughout the myocardium in most of rats treated with methamphetamine. The accompanying ultrastructural features included marked degeneration of cardiac mitochondria with fractured and disrupted cristae, hypercontraction of myofibrils, and loss of myofilament. In contrast, cardiac myocyte lesions were not observed in control rats. These myocardial lesions in rats treated with methamphetamine for 56 days resemble the cardiomyopathy associated with methamphetamine abuse in humans.

Animals↗

PubMed1996

Morphological and morphometric investigation of cardiac lesions after chronic administration of methamphetamine in rats.

The effects of chronic administration of methamphetamine on myocardium were morphologically and morphometrically studied in experimental models. Methamphetamine (1 mg/kg/day) was subcutaneously injected to five-week-old male Wistar Kyoto rats (WKY) for 8 weeks. Age- and sex-matched WKY served as controls. In light microscopy, scattered cytomyolysis, vacuolization, contraction bands and disarray of myofibers were prominent in methamphetamine-treated group; the electron microscopy showed degenerated mitochondria with disrupted cristae, myofibrillar hypercontraction and dissolution. Morphometric analysis was carried out using electron photographs and an image analyzer. The sizes of mitochondria and the number of mitochondria per unit area (100 microns2) in methamphetamine-treated group were significantly smaller than in the controls. No statistically significant difference was found regarding the percentage of myofibrillar area in cytoplasm between methamphetamine-treated and control groups. These findings show that chronic administration of methamphetamine can cause serious cardiac lesions and decrease in mitochondrial function.

Animals↗