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Biomedical subjects

Y Katsumata

Publications and source records attributed to Y Katsumata.

At least 19 recordsLinked to original sources
PubMed2002

Palinopsia and perilesional hyperperfusion following subcortical hemorrhage.

We report a patient who exhibited transient palinopsia and visual hallucinations. Disturbances initially included an auditory component and increasingly were localized to the left visual field. These events occurred during recovery from a right subcortical hematoma with left homonymous hemianopia. Single-photon emission computed tomography (SPECT) demonstrated extensive perilesional hyperperfusion involving parts of the right parietal, temporal, and occipital cortex. Perilesional hyperperfusion disappeared as the visual abnormalities diminished. We believe that excitatory neuronal activation in perilesional cortex during recovery contributed importantly to the transient abnormal perceptions.

Cerebral Hemorrhage↗
PubMed2001

Sensitive determination of four general anaesthetics in human whole blood by capillary gas chromatography with cryogenic oven trapping.

Four general anaesthetics, sevoflurane, isoflurane, enflurane and halothane, in human whole blood, have been found measurable with very high sensitivity by capillary gas chromatography-flame ionization detection (GC-FID) with cryogenic oven trapping upon injection of headspace (HS) vapor sample. To a 7-ml vial, containing 0.48 ml of distilled water and 20 microl of internal standard solution (5 microg), a 0.5-ml of whole blood sample spiked with or without anaesthetics, was added, and the mixture was heated at 55 degrees C for 15 min. A measure of 10 ml HS vapor was injected into the GC in the splitless mode at -40 degrees C oven temperature, which was programmed up to 250 degrees C. All four peaks were clearly separated; no impurity peaks were found among their peaks. Their extraction efficiencies were about 10%. The calibration curves showed good linearity in the range of 0.5-20 microg/ml; their detection limits were 10-100 ng/ml, which are almost comparable to those by previous reports. The coefficients of intra-day and day-to-day variations were 6.5-9.8 and 7.3-17.2%, respectively. Isoflurane or enflurane was also measured from whole blood samples in which three volunteers inhaled each compound.

Adult↗
PubMed2001

Sensitive determination of pethidine in body fluids by surface ionization organic mass spectrometry.

We have presented a simple and sensitive method for determining pethidine, a narcotic analgesic drug in body fluids by gas chromatography (GC)/surface ionization organic mass spectrometry (SIOMS). Good linearity was obtained in the range of 0.625-25 ng/ml of whole blood and urine by mass chromatography, and in the range of 0.05-2 ng/ml of whole blood by selected ion monitoring (SIM). Pethidine and diphenylpyraline (internal standard) were extracted from body fluids with Bond Elut Certify cartridges; their recoveries were above 95%. The detection limits (signal-to-noise ratio=3) were estimated to be 0.2 ng/ml of whole blood or urine by mass chromatography, 0.02 ng/ml of whole blood by SIM.

Analgesics, Opioid↗
PubMed2001

Analysis of 168 short tandem repeat loci in the Japanese population, using a screening set for human genetic mapping.

We devised a multiplex polymerase chain reaction (PCR) amplification and loading system for the convenient typing of 168 short tandem repeat (STR) polymorphic markers in a commercially available screening primer set for human linkage analysis. We genotyped all these 168 STR loci with 32 healthy unrelated Japanese, calculated allele frequencies at each STR locus, and performed three kinds of tests for Hardy-Weinberg equilibrium (HWE). Significant deviations from HWE in all three tests were observed at only three loci, and the average heterozygosity in the Japanese (0.733) was slightly lower than that in Caucasians (0.773). We also examined 32 Caucasians at some selected loci, to be compared with Japanese. Some markers showed greatly different heterozygosities or allelic distributions in Japanese and Caucasian populations. In two groups of STRs, those with and without irregular alleles (or interalleles), the former had a higher proportion of bimodal allelic distribution and possessed more alleles per locus than the latter. However, no significant differences in the observed and expected heterozygosities, or in the powers of discrimination, were found between the two groups. The present basic study of allele frequency databases of these STRs will contribute to further applications in forensic science and human genetics.

Gene Frequency↗
PubMed2001

Sensitive determination of midazolam and identification of its two metabolites in human body fluids by column-switching capillary high-performance liquid chromatography/fast atom bombardment-mass spectrometry.

Midazolam is a benzodiazepine and is widely prescribed for preanesthesia or general anesthesia. Overdose or intoxication cases of midazolam have been reported. In Japan, smuggled midazolam tablets could be involved in some criminal cases. Midazolam and its two metabolites were extracted by the solid-phase extraction method using Bond Elut SCX cartridges. The compounds were analyzed by on-line capillary high-performance liquid chromatography/fast atom bombardment-mass spectrometry. Midazolam and its two metabolites were well separated on the chromatogram, and each mass spectra gave [M+H](+) ion as a base peak. Deuterium-labeled midazolam was synthesized as an internal standard; it has enabled precise and reproducible quantitation of midazolam in blood samples. The calibration curve showed excellent linearity in the range of 2-200 ng/ml in spiked serum. The detection limit was 300 pg/ml (signal-to-noise ratio=3). The whole blood and urine samples from the victim of a homicide case were analyzed, and the midazolam concentration in the whole blood was estimated to be 163 ng/ml. The present method should be useful in clinical and forensic toxicology, because of its high sensitivity and specificity.

Journal Article↗
PubMed2001

Progesterone stimulates the expression of aminopeptidase A/angiotensinase in human choriocarcinoma cells.

In human placenta aminopeptidase A (APA), a principal enzyme that converts angiotensin II to angiotensin III, seems to be involved in angiotensin II metabolism during pregnancy. In this study, we investigated the possible effects of progesterone and estrogen on APA mRNA and protein levels in choriocarcinoma cells as a model for placenta. By RNase protection assay, progesterone induced higher APA mRNA levels than estrogen at the same concentration. Progesterone exhibited dose-dependent stimulation of APA mRNA, 1.8-fold increase at 10(-6) m for 24 h treatment. Progesterone at 10(-6) m increased APA mRNA levels within 12 h and in time-dependent fashion up to 24 h. Fluorescence-activated cell sorting analysis and measurements of APA activities revealed the induction of APA protein by progesterone. Expression of progesterone receptors (PR) and glucocorticoid receptors (GR) were determined in these cells by RT-PCR, which suggested that the progesterone's actions might be displayed through PR and/or GR. These findings may serve as a useful model to study the effects of progesterone on angiotensin II metabolism in placenta, although the physiological validity of these studies remains to be clarified.

Aminopeptidases↗
PubMed2001

Transcriptional regulation of human placental leucine aminopeptidase/oxytocinase gene.

Human placental leucine aminopeptidase (P-LAP) plays a major role in the clearance of oxytocin, which is a key hormone in regulating labour pain. To explore the transcriptional regulation of P-LAP gene expression in placenta, we performed systematic studies using human choriocarcinoma cells, BeWo and JEG-3, as a model of placental trophoblastic cells. Transient transfection and luciferase assays using various 5'-deleted P-LAP-luciferase constructs showed that the region from -297 to +49 of the transcription start site was responsible for promoter activity in these cells. Footprinting analysis with nuclear extracts from both cell lines demonstrated at least four sites for nucleoprotein interactions in this region (FP1 to FP4). Site-directed deletion of FP1-4 in luciferase assays indicated the significance of the FP3 region (-214 to -183) for high promoter activity in the cells. Electrophoretic mobility shift assays to identify the proteins interacting with DNA at FP3 revealed three retarded bands, one of which was generated by activator protein-2 (AP-2) binding. Our findings suggest that AP-2 may be one of the important factors regulating P-LAP gene expression in human placenta.

5' Untranslated Regions↗
PubMed2001

The application of minisatellite variant repeat mapping by PCR (MVR-PCR) in a paternity case showing false exclusion due to STR mutation.

A boy and a girl with their mother brought a paternity suit against an alleged but deceased father. We tested six conventional genetic markers, the AmpliType PM+ DQA1 and twelve STR loci the children and mother together with the alleged paternal grandparents. We also DNA typed the bloodstain found later in the alleged father's medical record. Only the result at D3S1358 in a nineplex STR system excluded the alleged father from parentage of the boy, whereas all markers were inclusive for the girl. Accordingly, we performed sequence analysis at D3S1358 to confirm the presence of a paternal exclusion or mutation. The sequence analysis indicated that the boy's allele 17 could have originated from either of the alleged father's allele 16 or 18 by a single-step mutation associated with slippage mutation in STR loci. We carried out minisatellite variant repeat mapping by PCR (MVR-PCR) at loci D1S8 (MS32) and D7S21 (MS31A) and mapped allele haplotypes of all individuals except the deceased alleged father. The MVR-PCR analysis showed that the boy has no inconsistency with the relationship between the alleged grandparents, and was very effective at increasing the paternity index (PI) value. We conclude that there is biological relationship between not only the girl but also the boy and the alleged father.

Adult↗
PubMed2001

A new triplex STR system without irregular alleles by silver staining and its potential application to forensic analysis.

In order to increase the discriminating power of DNA analysis in forensic science, we devised a new triplex STR system using three novel STR loci we previously reported, D14S299 (wglc5), D15S233 (wgldl), and 9q2h2. We designated this system a CDH triplex system. The CDH triplex system showed a high discriminating power, especially in Caucasians. This system is composed of three STR loci showing only regular tetranucleotide repeat alleles. We easily enlarged the databases mainly of Japanese, using this system, and compared them with those of Caucasian and Chinese. This CDH triplex system therefore appears to be useful for forensic practice.

Alleles↗
PubMed2001

[Estimating probabilities and dealing with mutations in paternity testing--verification of DNA testing with commercially available STR kits].

Since Jeffreys devised a DNA fingerprint in 1985, DNA analysis has been applied to paternity testing. The progress of the techniques, especially the development of polymerase chain reaction (PCR), makes it possible to type 10-15 short tandem repeat (STR) loci in paternity testing by a single test tube. When using a well qualified database, we can now obtain a paternity index (PI) as high as 10(6) in usual trio cases. Furthermore, the DNA testings are now applied to unusual cases, such as personal identification of Japanese war orphans left in China. Here, we reviewed how to calculate the PI likelihood ratio and exclusion probability in a trio case, a motherless case, parent identification without reliable evidence of mother and child relationship, and a sibling case. We also reviewed how to handle single exclusion cases usually derived from a single mutation that is no longer rare when many STR loci are used. Finally, we emphasized the importance of ethical, legal and social counseling for clients in paternity testing. From that point of view, paternity tests by mail should not be allowed because of lack of such counseling.

Female↗
PubMed2000

Ultrasensitive determination of phencyclidine in body fluids by surface ionization organic mass spectrometry.

Gas chromatography (GC)/surface ionization organic mass spectrometry (SIOMS) has been found to give much higher sensitivity for measurements of phencyclidine (PCP) than the conventional GC/electron impact (EI)-mass spectrometry (MS). Thus, we have established a detailed procedure for measurements of PCP in body fluids by both mass chromatography and selected-ion monitoring (SIM) of SIOMS using pethidine as an internal standard (IS). Good linearity was found in the range of 0.25-10 ng/mL of whole blood or urine, when measured by mass chromatography, and in the range of 0.025-1.0 ng/mL of whole blood by SIM. The recoveries of PCP and IS spiked to whole blood were 106 +/- 17% at 1 ng/mL and 113 +/- 11% at 5 ng/mL; that of IS was 97.8 +/- 10.4% at 5 ng/mL. The detection limits (signal-to-noise ratio = 3) were estimated to be 0.05 ng/mL of whole blood or urine by mass chromatography and 0.01 ng/mL of whole blood by SIM. The coefficients of intraday and interday variations were not greater than 10.3%. We could detect PCP from rat whole blood 2 h after subcutaneous injection of PCP (1 mg/kg) by mass chromatography. The mean PCP concentration in rat blood was 47.7 +/- 6.2 ng/mL (mean +/- SD, n = 4).

Animals↗
PubMed2000

Sensitive determination of mianserin and setiptiline in body fluids by gas chromatography with surface ionization detection (GC-SID).

Tetracyclic antidepressants, mianserin and setiptiline, in human body fluids have been found measurable with high sensitivity by gas chromatography (GC) with surface ionization detection (SID). The compounds in human whole blood or urine samples were extracted by solid-phase extraction using Bond Elut C(18) cartridges. The recoveries of both compounds from the body fluids were above 85%. For quantitation of mianserin, 25 ng of setiptiline was used as internal standard; and for quantitation of setiptiline, vice versa. The calibration curves for spiked whole blood or urine samples were linear in the range of 1.25-50 ng/ml. The detection limit of mianserin and setiptiline was about 1 ng/ml, which is comparable to those obtained by the previous GC-mass spectrometry methods. Our method seems very useful for determination of mianserin and setiptiline in forensic and clinical toxicology, because of high sensitivity, low background impurities and easy handling of the GC instrument.

Journal Article↗
PubMed2000

Immunoaffinity purification and characterization of native placental leucine aminopeptidase/oxytocinase from human placenta.

cDNA cloning of placental leucine aminopeptidase (P-LAP)/cystinyl aminopeptidase (CAP)/oxytocinase demonstrated that this enzyme is a type II integral membrane protein, which means that native P-LAP, found in placenta, is membrane-bound and that the soluble form of this enzyme, found in maternal sera, is most likely derived from the native form. The presence of the different forms of the protein makes it difficult to purify homogeneously. In the current study we prepared antibody specific to native P-LAP and used it to purify native P-LAP from microsomal fractions of human placenta to homogeneity, 5039-fold within 4 h, by immunoaffinity chromatography. Zn(2+)and Cu(2+)strongly inhibited the enzyme but Ca(2+)did not. Amastatin was a more potent inhibitor than bestatin and leupeptin. Using antibodies against native P-LAP, protein having 83 per cent of l -methionine insensitive Leu-p-nitroanilide cleaving activity, was immunoprecipitated from the microsomal fraction of human placenta. The availability of a specific antibody against native P-LAP permits the rapid purification and the preliminary immunoassay of the enzyme. Establishment of simple purification and assay methods for the native, membrane bound form of P-LAP pave the way to elucidating the roles and processing systems of this enzyme.

Amino Acid Sequence↗
PubMed2000

Usefulness of a toothbrush as a source of evidential DNA for typing.

We investigated the usefulness of a toothbrush as a source of DNA for an unidentified cadaver. Ten toothbrushes were obtained from ten individuals along with their peripheral blood. We recovered from 10 to 430 ng of DNA from all but one of the toothbrushes. All ten toothbrushes, including the one containing no detectable DNA by fluorometry, were typed correctly at all of the loci tested, including nine STRs. Three toothbrushes obtained in two actual deaths also identified two victims and one suspect. Therefore, toothbrushes seem to be useful as a source of evidential DNA for personal identification.

Cadaver↗
PubMed2000

[Granulocytic sarcoma presenting as an epidural mass with spinal cord compression].

A 73-year-old man was admitted because of back pain and paralysis of the lower extremities. Magnetic resonance imaging of the spine at the Th4-6 level, obtained after gadolinium injection, demonstrated abnormal signal intensity within the Th5-6 vertebral bodies and an extradural soft-tissue mass on the right posterior side of the spinal canal, compressing the thecal sac. The patient underwent prompt decompression with laminectomy, but this was unsuccessful. A biopsy sample of the mass revealed the histological features of granulocytic sarcoma, including diffuse infiltration of numerous cells containing cytoplasmic granules and immunohistochemical positivity for myeloperoxidase. Two months later, a subcutaneous soft-tissue mass appeared at the anterior chest wall, and this was confirmed to be granulocytic sarcoma by microscopic examination. Both of these tumors were radiosensitive, but the patient died of septic shock. Granulocytic sarcoma usually occurs in association with leukemia or other myeloproliferative disorders. However, it is rarely found before leukemia becomes evident in the peripheral blood or bone marrow; only eight such instances have been reported previously.

Aged↗
PubMed2000

[A case of moyamoya disease presenting with geographic mislocation, person misidentification and fantastic confabulation].

A 52-year-old woman presented with geographical mislocation (misidentification for place), person misidentification and fantastic confabulation as a result of cerebral infarction. Head MRI demonstrated a focal lesion in the right frontal lobe. Cerebral angiogram demonstrated occlusion in the circle of Willis with moyamoya vessels. The neuropsychological examination revealed memory impairment and frontal lobe dysfunction. The patient's misidentification for place and person as well as confabulation lasted for 1.5 months since admission, then gradually disappeared. We speculate that there existed a common mechanism for these three symptoms; i.e., misidentification and confabulation were based upon the impaired interpretation of the small events and partial objects in the surrounding circumstances, which might interfere with the appropriate integration and judgments of the outside information in general. The impaired monitoring and frontal dysfunction caused by the right frontal lesion appeared to be responsible for causing her deficits.

Brain↗