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T Kajii

Publications and source records attributed to T Kajii.

At least 55 records · Page 3Linked to original sources
PubMed1991

Pigmentary dysplasias in long survivors with mosaic trisomy 18: report of two cases.

We describe two patients, a 19-year-old girl and a 19-year-old boy, with mosaic trisomy 18 and pigmentary dysplasias. Both patients had profound growth and mental retardation, marked kyphoscoliosis, bushy eyebrows, bulbous nose, simple ears, and joint contractures - clinical manifestations of long survivors with mosaic or non-mosaic trisomy 18. In addition, the boy showed total asymmetry. Pigmentary dysplasias of the skin with hypopigmented whorls and streaks, initially absent or overlooked at the ages 2 and 15 years, were detected on close examination. It is advisable to check closely every long survivor with mosaic or purportedly non-mosaic trisomy 18 for pigmentary dysplasias.

Abnormalities, Multiple↗
PubMed1991

High-resolution banding in chromosomes of B lymphoblastoid cells and cultured skin fibroblasts.

High-resolution banded chromosomes were obtained in Epstein-Barr virus-transformed lymphoblastoid cells and cultured skin fibroblasts by aphidicolin synchronization, followed by inhibition of chromosome condensation by ethidium bromide. With this method, the chromosomes of 33.3% of lymphoblastoid cells and 48.7% of skin fibroblasts were high-resolution banded, and their mitotic indices were 1.5 and 2.7 times higher than those of control cultures.

Aphidicolin↗
PubMed1990

Characterization of a 5'-flanking region of the human liver/bone/kidney alkaline phosphatase gene: two kinds of mRNA from a single gene.

We have cloned the human liver/bone/kidney alkaline phosphatase (ALPL) gene using a liver-type ALPL cDNA as a probe. The gene is divided into 12 exons, and is likely to exist as a single copy in haploid genome. As compared with the gene isolated using a bone-type ALPL cDNA (Weiss et al., J. Biol. Chem. 263, 12002-12010, 1988), another leader exon specific for the liver-type ALPL mRNA was assigned about 3.4 kb upstream from exon 2 and the alternative splicing in the first exon was indicated. RNA blot analysis showed that three species of mRNA of 2.5, 4.1 and 4.7 kilobases were detected in liver and developmentally regulated.

Alkaline Phosphatase↗
PubMed1990

Cell type-dependent difference in the distribution and frequency of excess thymidine-induced common fragile sites: T lymphocytes and skin fibroblasts.

Common fragile sites were induced by excess thymidine in phytohemagglutinin-stimulated T lymphocytes from 4 normal individuals, and skin fibroblasts from 4 normal and 5 fra(X) positive individuals. The results indicate that the frequency and distribution of excess thymidine-induced fragile sites are different between these two types of cells. The sites at 1p13 and 2p11.2, induced in both types of cells, have not previously been described, and are thus considered to be excess thymidine-specific fragile sites. These findings extend and support our previous studies on cell type-dependent difference in aphidicolin-induced common fragile sites.

Adolescent↗
PubMed1990

Isolation of a Y chromosomal DNA sequence and its clinical application.

A 4.6 kb long, Y-specific DNA fragment was isolated from a flow-sorted human Y chromosomal library, and its male specificity was confirmed by Southern blot analysis. The fragment, designated as pY-80, was proven with an in situ hybridization experiment to have originated from the Yp11.2-Ypter region. Its 2,808 bp section was sequenced. The polymerase chain reaction proceeded with oligonucleotides flanking a 666 bp PstI-EcoRI fragment of the sequence as primers and a male genomic DNA as a template, but not with a female genomic DNA. Preliminary tests of samples of various sources successfully detected the Y-specific fragment in male-derived samples, including mouth wash, single hair roots, urinary epithelial cells, dried blood spots and amniotic fluid cells.

Base Sequence↗
PubMed1990

Role of human herpesvirus 6 infection in infants with exanthema subitum.

Twenty-two infants with exanthema subitum and their mothers were studied for human herpesvirus 6 (HHV-6) infection. HHV-6 was isolated from 13 of the 22 infants, in 5 infants by cultivation of their peripheral blood mononuclear cells and in the other 8 infants by cocultivation of their mononuclear cells with those from newborn cord blood. Of the 22 infants 19 showed a 4-fold or greater rise in HHV-6 antibody titers between the acute and convalescent stages of the disease. These findings support the contention that HHV-6 causes exanthema subitum. Attempts at isolation of HHV-6 from the saliva and peripheral blood mononuclear cells of the mothers of 14 of the 22 infants were unsuccessful. Serum samples from 22 mothers were all reactive to HHV-6 antigens, as evidenced by immunofluorescence and radioimmunoprecipitation analyses.

Antibodies, Viral↗
PubMed1990

Chronic nephritis, sensorineural deafness, growth and developmental retardation, hyperkinesis, and cleft soft palate in a 5-year-old boy. A new combination?

A 5-year-old Japanese boy showed nephritis similar to, but distinct from, that in Alport syndrome. Nephrotic syndrome without hematuria was noticed at age 2, although renal biopsy at age 4 revealed widespread irregular thickening of the glomerular basement membrane with splitting of the lamina densa on electron microscopy, characteristic of nephritis in Alport syndrome. Sensorineural deafness was noticed at age 4 weeks by no auditory brain stem response, unusually early for Alport syndrome. Goodpasture antigen and amyloid P component were found in the glomerular basement membrane. Thus, the antigenicity of the glomerular basement membrane was different from that in male patients with X-linked Alport syndrome. In addition, growth and developmental retardation, hyperkinesis, and cleft soft palate were seen. These features are a hitherto undescribed combination. The family history was negative for any of the features of the boy.

Child, Preschool↗
PubMed1990

Replication patterns of the fragile X in heterozygous carriers: analysis by a BrdUrd antibody method.

The replication status of the fragile X chromosomes was studied in short-term cultures of lymphocytes from six female heterozygous carriers. The fragile X was induced by adding 0.1 microM fluorodeoxyuridine during the last 24 h of culturing. The replication status of the X chromosomes was studied using a bromodeoxyuridine (BrdUrd) antibody method. BrdUrd was added (1) at a final concentration of 0.2 micrograms/ml during the early S phase of chromosome replication (16-10 h before harvest), (2) at 0.2 microgram/ml during the late S phase (the last 6 h of culturing), (3) at 20 micrograms/ml during the early S phase, and (4) at 20 micrograms/ml during the late S phase. BrdUrd that was incorporated into replicating chromosomes was detected by using a nuclease and BrdUrd monoclonal antibody. The frequency of the fragile X was reduced by BrdUrd treatment. The degree of reduction was more severe in the 20 micrograms/ml than in the 0.2 microgram/ml series and was more severe with late S than with early S treatment. Of the early- and late-replicating fragile X chromosomes, those which were actively replicating during a BrdUrd treatment were more reduced than the others. Thus, the average rate of early and late S treatment with 0.2 microgram BrdUrd/ml was assumed to be the closest reflection of the situation in vivo. There was no correlation between the average rate of the early replicating, active fragile X and the intelligence of the heterozygous carriers studied.

Adolescent↗
PubMed1990

Normal values for 24-h urinary protein excretion: total and low molecular weight proteins with a sex-related difference.

Urinary excretion of total and low molecular weight (LMW) (less than 40,000) proteins for a 24-h period was determined in 60 normal individuals, 30 men and 30 women, aged 21 to 44 years. 24-h urinary total protein excretion in men was 91.2 +/- 25.1 mg (mean +/- SD) (range: 40.2-146.8 mg), while that in women was 62.5 +/- 23.6 mg (range: 28.4-130.9 mg), as measured by a biuret method using bicinchoninic acid as a reagent. 24-h urinary LMW protein excretion in men was 37.3 +/- 13.6 mg (range: 12.7-62.7 mg), while that in women was 23.2 +/- 11.8 mg (range: 7.2-54.2 mg), as estimated by sodium dodecylsulfate-polyacrylamide gel electrophoresis of concentrated urine samples. Thus, a significantly higher (t-test, p less than 0.01) excretion of both the total and LMW proteins was found in men than in women. However, the percentage of the LMW proteins among the total proteins did not differ between the sexes: 40.3 +/- 7.5% (range: 21.7-54.9%) for men and 36.5 +/- 9.9% (range: 20.1-56.7%) for women.

Adult↗
PubMed1989

Human adenylate kinase deficiency associated with hemolytic anemia. A single base substitution affecting solubility and catalytic activity of the cytosolic adenylate kinase.

Adenylate kinase deficiency in the erythrocyte is a rare genetic disorder associated with hemolytic anemia. To determine the molecular basis of this disorder, we first cloned the normal gene encoding human cytosolic adenylate kinase (AK1) and determined the structure. The gene was 12 kilobase pairs long and was split into 7 exons. The structures of 5'- and 3'-flanking regions were determined by primer extension and RNA blot analysis. The results showed that two species of mRNA with 0.9 and 2.5 kilobases, which differed at the 3'-end portion, were generated by the AK1 gene. Alu sequences were found in the largest intron (intron 5) and in the noncoding region of exon 7. Next, both alleles of the AK1 gene were cloned from DNA of a patient bearing the adenylate kinase deficiency and their nucleotide sequences determined. A transition (C----T) was found in exon 6 on an allele, which resulted in an Arg to Trp (CGG----TGG) substitution at the 128th residue of AK1. Since chicken AK1 is highly homologous to human AK1 with respect to the amino acid sequence, we introduced an Arg to Trp substitution to chicken AK1 at the same position by oligodeoxynucleotide-directed mutagenesis. The mutant chicken AK1 expressed in Escherichia coli showed a reduced catalytic activity as well as a decreased solubility and a change in affinity to phosphocellulose. Thus it was considered that the observed C----T transition was a cause of the decreased AK1 activity of the patient's erythrocyte. Analysis on phosphocellulose chromatography of erythrocyte AK1 of the patient and parents revealed that the patient's mutant allele was derived from the mother.

Adenylate Kinase↗
PubMed1989

Effect of pH on giant cell formation induced by human immunodeficiency virus ( HIV ).

The rate of multinucleated giant cell formation by the fusion of HIV chronically infected human T-cells (MOLT-4/HIV) and HIV uninfected MOLT-4 cells was examined under various pH conditions. The number of giant cells formed under the different pH conditions was quantitatively monitored by "MULTISIZER". The rate of giant cell formation was significantly less at the pH lower than 6 but not influenced at higher pH. Plaque assay under various pH conditions revealed that inhibition of giant-cell formation at lower pH was not due to the influence over the recognition between gp120 of HIV and CD4 molecules.

Antigens, Differentiation, T-Lymphocyte↗
PubMed1989

Cell type-dependent difference in the distribution and frequency of aphidicolin-induced fragile sites: T and B lymphocytes and bone marrow cells.

The distribution and frequency of aphidicolin-induced common fragile sites were studied in Epstein-Barr virus-transformed B lymphocytes from eight normal individuals, and in bone marrow cells from six children in remission from malignant blood diseases. PHA-stimulated helper T lymphocytes from the same individuals were also studied. These cells were cultured in MEM, and treated with 0.2 microM aphidicolin for 26 h. The results, together with those of our previous study on cultured skin fibroblasts, indicated that the distribution and frequency of aphidicolin-induced fragile sites are different among different types of cells.

Adult↗
PubMed1989

Disomic homozygosity in 21-trisomic cells: a mechanism responsible for transient myeloproliferative syndrome.

Nine patients with transient myeloproliferative syndrome (TMS) with or without Down syndrome (DS) phenotype were studied cytogenetically, particularly with regard to the origin of trisomy 21. Of six DS patients, five had standard trisomy 21 and one a mosaic consisting of 21-tetrasomic, trisomic and disomic cell lines. The other three non-DS patients were mosaics with both 21-trisomic and -disomic cell lines. In all nine patients, the leukemoid cells in TMS stage were largely or exclusively composed of trisomy or tetrasomy 21, an indication that the additional chromosome(s) 21 plays an important role in the occurrence of TMS. Sequential Q- and R-banding analysis of heteromorphisms demonstrated that all these patients had a duplication of a chromosome 21, as revealed by an "aab" pattern, regardless of DS or normal phenotype or parental origin of the extra chromosome 21. Irrespective of the possibility of recombination, the "aa" chromosomes are homozygous, i.e. show disomic homozygosity: this may in turn result in the duplication of a gene that controls the proliferation of the myelogenous cells, thereby leading to TMS.

Chromosome Banding↗
PubMed1989

Fibroblast-specific common fragile sites induced by aphidicolin.

The distribution and frequency of aphidicolin-induced common fragile sites were studied in chromosomes of cultured skin fibroblasts and PHA-stimulated lymphocytes from five normal individuals; 0.2 microM aphidicolin was added for the last 26 h of culture. Skin fibroblasts from five fra(X)-positive patients were also studied in the same manner. Fragile sites most frequently found in fibroblasts from normal individuals were 3q26.2, 7q11.23, 16q23, 1p31, 10q11.2, 12q23 and 7q31, whereas those in lymphocytes from the same individuals were 3p14, 16q23, Xp22, 7q32 and 14q24. The distribution of fragile sites in fibroblasts from fra(X)-positive patients was essentially identical with that in normal individuals. The average number of gaps and breaks in 100 metaphases was 36.8 in fibroblasts from normal individuals, 113.8 in those from fra(X)-positive patients, and 279 in lymphocytes from normal individuals. Their rates of chromosome-type breaks and gaps were 7.9%, 29.7% and 54.5%, respectively. Thus, the distribution and frequency of aphidicolin-induced fragile sites were different between skin fibroblasts and lymphocytes, possibly reflecting differences in their DNA replication sequence or gene activity.

Adult↗