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Biomedical subjects

Y Katsumata

Publications and source records attributed to Y Katsumata.

At least 37 records · Page 2Linked to original sources

Structural organization of the 5'-end and chromosomal assignment of human placental leucine aminopeptidase/insulin-regulated membrane aminopeptidase gene.

Placental leucine aminopeptidase (P-LAP) which is identical with cystine aminopeptidase as oxytocinase was found to be a homologue of rat insulin-regulated membrane aminopeptidase (IRAP) by cDNA cloning. In this study, we confirmed 5'-end cDNA sequence of P-LAP and isolated genomic clones containing the upstream region of human P-LAP gene. The transcription initiation sites determined by primer extension located 478 and 480 bp upstream of the initiation methionine codon, 38 bp downstream of TATA box-like motif. The 5'-flanking region of human P-LAP gene contained DNA-binding motifs for several ubiquitous transcription factors such as SP1 and AP2. Chromosomal localization by fluorescence in situ hybridization showed that the gene was assigned to 5q14.2-q15 of the human chromosome. This study establishes the genetic basis for P-LAP gene research, thereby leading to better understanding of the molecular mechanism underlying the P-LAP gene.

Aminopeptidases↗

Sequence analysis of alleles at a microsatellite locus D14S299 (wg1c5) and population genetic comparisons.

In order to increase the discriminating power of DNA analysis in personal identification, we evaluated the forensic utility of the microsatellite locus D14S299 (wg1c5) in the Japanese population and also in the Chinese and Caucasian populations. Twelve different alleles were identified in length by gel electrophoresis with silver staining. The major alleles in Japanese were sequenced and designated as the numbers of the variable repeats (GGAT or GGAA). There were five variable regions and extensive homoplasy was found. However, the allele fragment lengths were in 4 bp increments and no "interalleles" were found. The estimated heterozygosity and the polymorphism information content (PIC) were 0.726 and 0.689, respectively in Japanese. Those in Chinese (0.743 and 0.704) were similar to those in Japanese, while those in Caucasians (0.812 and 0.781) were much higher. After adjacent alleles were combined to yield at least five entries, statistical analysis was performed. The power of discrimination (PD) was 0.887 in Japanese, 0.895 in Chinese and 0.935 in Caucasians and no significant deviations from the Hardy-Weinberg equilibrium were found in the three populations. We retyped all apparently homozygous samples using an alternative pair of flanking primers and found them to be true homozygotes. D14S299 appears to be a useful STR locus for forensic practice.

Asian People↗

Large-scale preparation of high-molecular weight DNA from buccal mucosa.

Four non-invasive methods of sampling DNA from buccal mucosa, simple rinses, scrubbing with cotton balls, scrubbing with toothbrushes and rinses after scrubbing with toothbrushes, were investigated. Scrubbing with toothbrushes yielded 5.79 +/- 5.56 microg of DNA rich in high-molecules, while less than one eighth the amount was recovered by scrubbing with cotton balls. Rinses after scrubbing with toothbrushes gave 50.0 +/- 46.0 microg of DNA and simple rinses 34.4 +/- 35.7 microg, although the DNA was considerably degraded. DNA specimens obtained from buccal cells were shown to be more or less in the process of degradation including apoptosis. For minisatellite analysis, only DNA prepared by scrubbing with toothbrushes could be used, while all specimens could be applied to PCR analyses. Since scrubbing with toothbrushes is painless and harmless, we recommend this method. Subsequent rinsing will yield a large amount of DNA suitable for many PCR analyses.

Journal Article↗

Evaluation of two new STR loci 9q2h2 and wg3f12 in a Japanese population.

Two short tandem repeat (STR) loci (9q2h2 and wg3f12) have been evaluated in a Japanese population. Ten and seven different alleles were observed in 9q2h2 and wg3f12 respectively. 9q2h2 displayed simple polymorphism in tetrameric repeat structure; by contrast, wg3f12 contained variable numbers of tetrameric repeats and a 30-bp deletion/insertion polymorphism. No "interalleles" were found. The expected heterozygosities of 9q2h2 and wg3fl2 were 0.749 and 0.574, respectively. No deviation from Hardy-Weinberg equilibrium was found.

Journal Article↗

Evaluation of the paternity probability on an application of minisatellite variant repeat mapping using polymerase chain reaction (MVR-PCR) to paternity testing.

Minisatellite variant repeat (MVR) mapping using polymerase chain reaction (PCR) was applied to a practical case of paternity testing to evaluate the paternity probability. In order to obtain single allele mapping by allele-specific MVR-PCR, three flanking polymorphic sites for each of the MS31A and MS32 loci were investigated and all three individuals were typed as heterozygous for at least one flanking polymorphic site at each locus. Allele-specific MVR-PCR was then performed using genomic DNA. It was confirmed that one allele in the child was identical to that from the mother and the other one in the child was identical to that from the alleged father. Mapped allele codes were also compared with those in the database by dot-matrix analysis, and no identical allele was found although some motifs were shared with Japanese alleles. The paternity index and the probability of paternity exclusion in the case at these two MVR loci were calculated using the presumed values of the allele frequencies. These studies seem to illustrate the practical value of MVR mapping of MS31A and MS32 loci in paternity testing.

Journal Article↗

Purification of nuclear DNA from single hair shafts for DNA analysis in forensic sciences.

The typing of nuclear DNA from hair shafts has often been unsuccessful to date. We tried to type one of the nuclear DNA loci, HLA-DQA1, from hair shafts, using an efficient cetyl-trimethyl ammonium bromide (CTAB) precipitation for DNA purification and a sensitive semi-nested PCR. After thorough washing with ethanol and water, hair shafts were digested by proteinase K in the presence of dithiothreitol, followed by a purification step including CTAB-DNA precipitation. The specific region of HLA-DQA1 gene was amplified by the semi-nested PCR, and the amplified products were cloned and sequenced. The HLA-DQA1 genotype was determined by comparing the sequence to the known sequence of each allele. All genotypes of HLA-DQA1 were successfully typed with hair shafts from six known heterozygotes, although one of them showed the predominant appearance of one allele. For correct typing, a template DNA equivalent to a hair shaft of 5 or 10 cm in length was necessary. Without the CTAB-DNA precipitation step, DNA extract from such hair shafts inevitably contains enough melanin to inhibit PCR. The present results suggest that hair shafts can be used for the typing of nuclear DNA loci.

Journal Article↗

Tetrameric short tandem repeat (STR) system D15S233 (wg1d1): sequencing and frequency data in the japanese and Chinese populations.

We evaluated the forensic usefulness of D15S233 (wg1d1), a tetrameric short tandem repeat (STR) locus, in the Japanese and Chinese populations. Typing was performed by denaturing polyacrylamide gel electrophoresis followed by silver staining. Nine different alleles were found in 472 Japanese chromosomes and seven in 186 Chinese chromosomes. 102 alleles sequenced were composed of two kinds of repeats (AGGA and GGGA). All alleles differed in size by one tetranucleotide repeat unit, and no insertion or deletion was found. The expected unbiased heterozygosities in Japanese and Chinese were 0.766 and 0.785, respectively. No significant deviations from the Hardy-Weinberg equilibrium were found in either population. We retyped all samples using an alternative pair of flanking primers in order to detect any spurious appearances of homozygotes due to sequence variation at the primer annealing site. One heterozygous sample had unbalanced density bands when the original primer set was used, but equal density bands when our newly designed primer set was used. Sequencing analysis revealed that the sparser allele had one nucleotide substitution near the 5' end of the annealing site of the original primer region. Thus, all apparently homo/heterozygous samples were thought to be truly homo/heterozygous. We also applied the D15S233 locus to paternity testing and forensic identification. Our results suggest that this locus should be a very useful STR locus for forensic practice in Japanese and Chinese.

Journal Article↗

The potential contribution of MVR-PCR to paternity probabilities in a case lacking a mother.

Minisatellite variant repeat (MVR) mapping using the polymerase chain reaction (PCR) was applied to a paternity case lacking a mother to evaluate the paternity probability. After three flanking polymorphic sites at each of MS31A and MS32 loci were investigated from the child and alleged father, allele-specific MVR-PCR was performed using genomic DNA. It was confirmed that one allele in the child was identical to that in the alleged father at both loci. Mapped allele codes were compared with allele structures established from population surveys. No perfect matches were found although some motifs were shared with other Japanese alleles. The paternity index and probability of paternity exclusion at these two MVR loci were then estimated, establishing the power of MVR-PCR even in paternity cases lacking a mother.

Alleles↗

[Tests for Hardy-Weinberg equilibrium in Japanese population].

In population genetics, the absence of the departure from Hardy-Weinberg equilibrium (HWE) is usually tested when a population study of a certain DNA marker is performed to show the observed allele frequencies represent those of the whole population. The goodness-of-fit test (chi 2 test) assuming chi 2 approximation has frequently been used with classical blood type markers having a few alleles. However, new tests suitable for DNA markers having many alleles, such as homozygosity test, likelihood ratio test and Guo-Thompson's (G-T') exact test, have recently been devised. In the present study, appropriate tests for HWE was studied using population data of 206 Japanese individuals with 9 different short tandem repeat loci. Firstly, we found that the recommendation of NRC II for the treatment of rare allele frequencies (If a bin in the database contains fewer than five entries, it is pooled with adjacent bins so that no bin has fewer than five) is quite reasonable for personal identification in forensic sciences. Secondly, we proposed that homozygosity test, likelihood ratio test and G-T's exact test should be applied altogether and HWE of the sample population should be valid only when all of the three tests were cleared.

Asian People↗

DNA typing of primate major histocompatibility complex (Mhc)-DQA1 locus by PCR and dot blot hybridization.

Non-human primates (NHPs) are increasingly utilized as models to investigate different aspects of immune responses against self (autoimmunity) and foreign antigens. These animals provide valuable models for testing the efficacy of candidate vaccines against pathogens such as human immunodeficiency virus (HIV) and also fertility regulating agents (immunocontraceptives). In order to fully understand the effects of vaccination, it may be necessary to elucidate the immunogenetic background of these animals. The major histocompatibility complex (Mhc) molecules play an important role in the generation of effective immune responses. Serological techniques have been used in the identification of human leukocyte antigens (HLA) necessary for cross-matching organs and tissues for transplantation. However, the application of this technique for typing monkey Mhc alleles has been hampered by unavailability of well characterized immunological reagents. Polymerase chain reaction (PCR)-based techniques such as restriction fragment length polymorphism (RFLP) and sequence-specific oligonucleotide probe hybridization (SSOP) have been extensively used for typing HLA-DP, DQ and DR alleles. A commercially available Kit (AmpliTypeR) designed for amplification and typing of HLA DQalpha alleles is routinely used in typing DNA samples for forensic casework. In the present study, we have evaluated this kit for possible application in routine typing of primate DQA1 alleles. Genomic DNA from ten African primate species (23 individuals) was isolated from peripheral blood lymphocytes and polymorphic second exon of DQA1 locus amplified using GH26 and GH27 PCR primers. The PCR products were hybridized on a nylon membrane containing immobilized sequence-specific oligonucleotide probes. Our results show seven of the nine probes hybridizing with primate DQA1 alleles, indicating that typing of equivalent primate alleles can be accomplished at lower stringency conditions. However, it may be necessary to design additional oligonucleotides probes (based on available primate DQA1 sequences) to improve the discriminating power of this kit for use in routine typing of Old World monkey DQA1 alleles.

Animals↗

[Analysis of MS31A in Chinese using MVR-PCR].

Allele-specific MVR-PCR can be performed on genomic DNA to sample the diversity of allelic structure at MS31A (D7S21 locus). Three polymorphic positions in MS31A 5' flanking DNA were typed from 100 unrelated Chinese in this study. The results showed that single alleles could be mapped from genomic DNA in above 80% samples of Chinese in this locus. The distribution of haplotypes of unrelated Chinese was also reported in this paper.

Alleles↗

Allele distribution at nine STR loci--D3S1358, vWA, FGA, TH01, TPOX, CSF1PO, D5S818, D13S317 and D7S820--in the Japanese population by multiplex PCR and capillary electrophoresis.

Nine tetranucleotide short tandem repeat (STR) loci, D3S1358, vWA, FGA TH01, TPOX, CSF1PO, D5S818, D13S317 and D7S820, were analyzed in the Japanese population with a newly released kit for personal identification using multiplex PCR with fluorescent-labeled primers following capillary electrophoresis. The observed heterozygosities were 0.67, 0.77, 0.82, 0.61, 0.62, 0.73, 0.78, 0.81 and 0.74, respectively, and the combined discrimination power of the nineplex was 0.9999999991. None of the nine loci deviated from Hardy-Weinberg equilibrium expectations using the chi-square test, homozygosity test, likelihood ratio test and exact test after the grouping of the alleles. The nine STR loci allele frequencies were significantly different from those of other ethnic populations.

Alleles↗

Comparison of complications of vaginal hysterectomy in patients with leiomyomas and in patients with adenomyosis.

We reviewed 1246 vaginal hysterectomies performed at Handa City Hospital between January 1984 and December 1996. We divided the patients into 2 groups: those with leiomyomas (n = 893) and those with adenomyosis (n = 353). There was no difference in operative time and estimated blood loss between the 2 groups when analyzed by uterine weight. However, adenomyosis was associated with an increased risk of bladder injury.

Adult↗

Magnetic resonance imaging with gadolinium-diethylenetriamine pentaacetic acid is useful in assessment of tubal patency in a patient with iodine-induced hypothyroidism.

A 32-year-old woman presented for evaluation of primary infertility. Because she had a history of iodine-induced hypothyroidism, conventional hysterosalpingography was contraindicated. Tubal patency was assessed by magnetic resonance imaging (MRI) after infusion of gadolinium-diethylenetriamine pentaacetic acid (Gd-DTPA). Visualization of the contrast medium in the peritoneal cavity revealed tubal patency. Our case indicates that MRI with gadolinium-diethylenetriamine pentaacetic acid is a safe, simple, and easy way to confirm that at least one tube is patent when a patient is at risk for hysterosalpingography. To our knowledge, this is the first report that tubal patency was diagnosed on MRI.

Adult↗

Gonadotropin-releasing hormone-induced elevation of serum hCG in choriocarcinoma: a case report.

We evaluated the effect of GnRH on the serum hCG level in gestational trophoblastic disease (GTD). Five patients with GTD were studied. Three patients had hydatidiform mole (two complete and one partial mole) and two had choriocarcinoma. Blood samples were collected immediately before and 30, 60 min after the 100 microg GnRH iv injection, followed by hCG assay. Only one case of choriocarcinoma demonstrated an hCG increase after intravenous administration of GnRH (positive GnRH test). In that case, the hCG level dropped to the normal range after eight cycles of chemotherapy but the GnRH test was still positive, suggesting the existence of viable cancer cells. Since the GnRH test became negative, no increase in hCG has been observed, indicating that the patient achieved complete remission. Although a positive GnRH test is not common in GTD, GnRH test before treatment might be useful to find a positive case where the test can be repeated to determine complete remission and the time when the chemotherapy may be discontinued.

Adult↗

[A study for effects on pre- and postnatal development, including maternal function in rats treated subcutaneously with magnesium sulfate].

Magnesium sulfate, at dose levels of 250, 500 and 1000 mg/kg, was administered subcutaneously three times daily to Crj:CD(SD) female rats from day 15 through day 20 of gestation. The effects of the compound on dams and F1 animals were examined. In the dams, decreased food consumption was observed in the 500 and 1000 mg/kg groups. Hypolocomotion, pronation, bradypnea and decreased body weight gain were observed in the 1000 mg/kg group. But there were no effects on the delivery or lactation conditions and necropsy from administration of the test article. In the F1 animals, low body weight, delays in differentiation (eruption of lower incisor, opening of eyelid) and reversible change in ribs (wavy rib) were observed in the 1000 mg/kg group. But there were no effects from administration of the test article in viability, functional examinations, behavior tests or reproductive ability. Based on the above results, under the conditions of this study, it was concluded that the non-toxic dose levels for general toxicological effects on dams was 3 x 250 mg/kg/day, for reproductive ability of dams was 3 x 1000 mg/kg/day, and for development of F1 animals was 3 x 500 mg/kg/day.

Animals↗

Familial hemiplegic migraine with irreversible brain damage.

Familial hemiplegic migraine (FHM) is an autosomal dominant syndrome characterized by recurrent episodes of varying degrees of hemiparesis associated with migraine. The aura including hemiparesis may be prolonged and in severe attacks may often be associated with confusion or coma. We describe a case of FHM whose aura was atypically prolonged and resulted in irreversible brain deficit which on magnetic resonance imaging (MRI) was suggestive of cortical hyperperfusion. A subsequent MRI showed left brain atrophy.

Adult↗