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E Matsunaga

Publications and source records attributed to E Matsunaga.

At least 37 records · Page 2Linked to original sources
PubMed1988

Molecular analysis of Japanese delta beta-thalassemia.

A DNA fragment containing the deletion junction region from a Japanese individual with homozygous delta beta-thalassemia has been cloned. A clone containing the normal DNA surrounding the 3' breakpoint of this deletion and a clone carrying the G gamma- and A gamma-globin genes of this patient were also isolated. Sequences of the deletion junction and both gamma-globin genes were determined. A comparison of these sequences with previously determined sequences of the normal counterparts revealed that the 5' breakpoint is located between 2,134 and 2,137 base pairs (bp) 3' to the polyA site of the A gamma-globin gene, the 5' breakpoint is located just downstream of the 3' border of the fetal gamma-globin duplication unit, and no molecular defects are evident within the gamma-globin gene region. A comparison between the sequences of the normal DNA surrounding the 3' breakpoint and the normal DNA surrounding the 5' breakpoint shows that deletion is the result of a nonhomologous recombination event. There are A+T-rich stretches near the 5' and 3' breakpoints in the normal DNA, and a portion of an Aly repeat is located in the region 3' to the 3' breakpoint. Southern blot analysis using probes 3' to the beta-globin gene showed that the deletion extends in the 3' direction further than any other deletions associated with delta beta-thalassemia and hereditary persistence of fetal hemoglobin (HPFH) heretofore reported. These results are discussed in terms of the mechanism generating large deletions in mammalian cells and three models for the regulation of gamma-globin and beta-globin gene expression in humans.

Adult↗
PubMed1987

An apparent discrepancy between chain length and electrophoretic mobility of restriction fragments: a case of human mitochondrial DNA.

DNA sequence analysis and electrophoresis in denaturing gel revealed that a 60 base pair insertion which had been previously postulated on the basis of native polyacrylamide gel electrophoresis of mitochondrial DNA from Japanese (Horai and Matsunaga 1986) did not exist at all. Unusual behavior of certain restriction fragments in native polyacrylamide gels apparently resulted in what appeared to be an insertion. Further study revealed that this behavior is most likely due to secondary structures of the fragments. The results of the present study suggest that adequate care should be taken when assessing molecular weights of restriction fragments by native polyacrylamide gel electrophoresis.

Base Sequence↗
PubMed1987

Age-related changes of the dermatan sulfate containing small proteoglycans in bovine tendon.

Sulfated proteoglycans of fetal, newborn and adult bovine tendon are extracted with neutral salt and then with 4 M guanidine HCl in the presence of proteinase inhibitors. Dermatan sulfate containing small proteoglycans are separated from chondroitin sulfate rich proteoglycans by CsCl-gradient centrifugation, by affinity chromatography using concanavalin A and by molecular sieve chromatography. These proteoglycans are comprised of a core protein with an average Mr of about 53,000 on polyacrylamide gel electrophoresis with SDS and of dermatan sulfate side chains with Mr 25,000-38,000 by gel chromatography. The tryptic peptides patterns observed in the small proteoglycans from newborn calf and adult bovine tendon are identical but are distinct from those of embryonic calf tendon. The patterns of the tryptic peptides of the core proteins from embryonic calf tendon are similar to those from the dermatan sulfate proteoglycans of calf skin. These results indicated that genetically independent genes of the core proteins from dermatan sulfate proteoglycans in tendon tissues were expressed by aging.

Aging↗
PubMed1987

Acidic glycosaminoglycans, isolation and structural analysis of a proteodermatan sulfate from dermatosparactic calf skin.

Dermatan sulfate and hyaluronic acid are the major glycosaminoglycan components of dermatosparactic and normal calf skin but the ratio of hyaluronic acid to dermatan sulfate is 50-70% higher in dermatosparactic calf skin than that in normal calf skin. Hyaluronic acid in normal calf skin could be extracted to 93% of the total by NaCl and guanidine hydrochloride, while in dermatosparactic calf skin 57% of hyaluronic acid remained in the insoluble material after NaCl and guanidine hydrochloride extraction. The recovery of proteodermatan sulfate in NaCl extracts was similar in normal and dermatosparactic skin. The amount of proteodermatan sulfate extracted in guanidine hydrochloride form normal calf skin was 2-4 fold higher than that from dermatosparactic calf skin. No significant difference between dermatosparactic and normal calf skin proteodermatan sulfate could be detected in terms of size of the core protein (Mr = 55,000) by sodium dodecyl sulfate polyacrylamide gel electrophoresis, amino acid analysis, immunological cross-reactivity using polyclonal antibodies against either dermatosparactic or normal calf skin core protein, tryptic peptides or size of dermatan sulfate chains (Mr = 17,000-18,000) on gel chromatography.

Animals↗
PubMed1987

[Genetics and epidemiology of retinoblastoma].

Recent studies of genetic epidemiology of retinoblastoma are reviewed, and major conclusions drawn are as follows: Retinoblastoma occurs in heritable or nonheritable form. The primary genetic change in the heritable form is a point mutation or deletion at a locus on 13 q 14. For the genesis of a tumor in either form, the loss or inactivation of both alleles at this locus is a prerequisite, although additional events may be needed for its development. Information about environmental risk factors for the occurrence of heritable or nonheritable retinoblastoma is still meager. Although viral etiology for nonheritable tumor cannot be excluded, an extensive epidemiologic study revealed no seasonal variation in the births of 675 patients with sporadic unilateral cases, a great majority of which may be regarded as due to somatic mutation. Moreover, there was no paternal age effect at all on the occurrence of 225 sporadic bilateral cases. Paternal exposure to ionizing radiation or chemical mutagens, which should have an accumulated effect with advancing age, does not seem to play a major role in the production of germinal mutation at the Rb locus. Family studies show that host resistance genes at other loci can modify the process of tumor development when the primary genetic change is already present in all the target cells. Unaffected gene carriers may be regarded as inherently resistant to tumor formation, whereas persons who present early onset of bilateral tumors are the most susceptible. In certain families, however, non-expression in the carriers may be due to chromosomal rearrangement in a balanced state.

Carboxylesterase↗
PubMed1986

Mitochondrial DNA polymorphism in Japanese. II. Analysis with restriction enzymes of four or five base pair recognition.

Mitochondrial DNA (mtDNA) from 116 Japanese was analyzed with nine restriction enzymes that recognize a four or five base pair sequence. The sizes of the mtDNA fragments produced by digestion by each enzyme were compared after gel electrophoresis. Double digestion experiments indicated that, in the coding region from URF2 (unidentified reading frame) to tRNAAsn (bp 5274-5691), there is an insertion of about 60 base pairs (bp) compared with the published mtDNA sequence, which is common to all individuals in the present sample. A total of 95 different morphs were detected with the nine enzymes, 60 of which have not been documented previously. Based on a comparison of the cleavage maps of all individuals, 62 different combinations of restriction types were observed. By pairwise comparison of each restriction type, the average number of nucleotide substitutions per nucleotide site (delta) was estimated to be 0.0026. Phylogenetic analysis of the present data indicates that at least two distinct lineages exist in the Japanese population.

Base Sequence↗
PubMed1986

Two species of dermatan sulfate proteoglycans with different molecular sizes from newborn calf skin.

Two species of dermatan sulfate-proteoglycans (DS-PGs) were isolated from calf skin. The first species, PDS-H (high-molecular-weight proteodermatan sulfate), contains the core protein with a molecular weight of either about 55,000 or 53,000. Both the core proteins are capable of binding to concanavalin A (Con A). The second species, PGs-L (low-molecular-weight proteoglycan containing dermatan sulfate and/or chondroitin sulfate), contains a core protein of Mr = 20,000 that did not bind to Con A. Tryptic peptide mappings revealed that Mr = 55,000 core protein and Mr = 53,000 core protein were of the same origin. However, the tryptic peptides and the amino acid composition of PGs-L core protein were completely different from those of PDS-H core proteins. The polyclonal antibodies against Mr = 55,000 core protein reacted with both the core proteins of Mr = 55,000 and Mr = 53,000 but not with the core protein from PGs-L. The DS was found to be the only glycosaminoglycan component of PDS-H. That is, the glycosaminoglycan from PDS-H was composed of 46% iduronosylhexosamine units and 54% glucuronosylhexosamine units, while the glycosaminoglycan of PGs-L was composed of 30% iduronosylhexosamine units and 70% glucuronosylhexosamine units.

Animals↗
PubMed1986

Two cases of adult T-cell leukaemia.

A 70-year-old male and a 46-year-old female, both living in Japan, were seen because of multiple erythematous papules and plaques on the trunk and extremities. The peripheral white blood cell counts were increased to 30,000-80,000/mm3. The majority of white cells had characteristic lobulated and deeply indented nuclei. The patients and most of their family members had anti-ATLV antibody. Using an OKT series of monoclonal antibodies the tumour cells were found to be T-cells. Trisomy 21 was detected in the first case and ATL virus proviral DNA in the second.

Aged↗
PubMed1985

A novel deletion in delta beta-thalassemia found in Japan.

High molecular weight DNA from a Japanese individual homozygous for delta beta-thalassemia was analyzed by the blot hybridization technique of Southern. Results indicated a large deletion of the non-alpha-globin gene cluster, starting in the vicinity of 3' to the A gamma-globin gene and extending through the 3' side of the beta-globin gene. Persistent expression of the gamma-globin gene in adult life has been supposed to be caused by loss of a region located about 3-4 kb 5' to the delta-globin gene from comparison of the extents of deletions in several different forms of delta beta-thalassemia and HPFH (hereditary persistence of fetal hemoglobin). But the novel deletion found in the present case of delta beta-thalassemia suggests that the above putative regulatory region does not have this effect on expression of the gamma-globin gene. Some explanations of expression of fetal type globin genes in this delta beta-thalassemia are discussed.

Base Sequence↗
PubMed1985

An acidic glycoprotein (100-K fucose-rich glycoprotein) from calf skin.

A new acidic glycoprotein was isolated from 4 M-guanidiunium chloride which had been extracted from neutral-salt-insoluble fractions of neonatal calf skin. During the process of purification, the glycoprotein co-migrated with proteodermatan sulphate and its sugar components mainly consisted of fucose, mannose and hexosamine. A broad band obtained by sodium dodecyl sulphate (SDS)-polyacrylamide gel electrophoresis suggested that the molecular weight was 100,000. High-voltage electrophoresis, revealed acidic fragments in its tryptic peptides, while its oligosaccharide chains were shown to have on acidic nature by electrophoresis on a cellulose acetate membrane. These results show that the glycoprotein differs from other glycoproteins (fibronectin, laminin, entactin, nidogen and the 31-K protein of chondrocyte membrane) which have been reported in connective tissues.

Animals↗
PubMed1985

Characterization of 2,7-anhydro-N-acetylneuraminic acid in human wet cerumen.

A molecular species of sialic acid was isolated in a free form from cerumen of the wet type, but not of the dry type, by an ion-exchange column chromatography and preparative high-performance liquid chromatography. Structural analysis of this sialic acid was performed by gas-liquid chromatography/mass spectrometry with chemical ionization (CI) and electron ionization (EI). In the CI mass spectra, the protonated molecular ion of the trimethylsilyl derivative was observed at m/z 580. and that of the methyl ester-trimethylsilyl derivative was at m/z 522. In the EI mass spectrum, the methyl ester-trimethylsilyl derivative gave characteristic ions at m/z 506, 462, 418, 416, 328, 316, 238, 228, 205, 186, and 173. This mass spectrum was identical with that of 2,7-anhydro-N-acetylneuraminic acid, which was reported by Lifely and Cottee (Carbohydr. Res. 107, 187-197, 1982) as the mass spectrum of a by-product prepared from N-acetylneuraminic acid by methanolysis. These results indicate that the compound in the wet cerumen is 2,7-anhydro-N-acetylneuraminic acid. Since this sialic acid species could not be detected in cerumens of the dry type, its formation in the wet type may be controlled by an autosomal dominant gene.

Cerumen↗
PubMed1985

A syndrome with nodular erythema, elongated and thickened fingers, and emaciation.

A 5-year-old boy had a nodular erythema, elongated and thickened fingers, and emaciation. His condition was a rare congenital disease inherited as an autosomal recessive trait. Eleven cases have been previously reported in the Japanese literature. The onset is early in childhood, and nodular erythema is an essential and initial finding. Growth retardation and emaciation progress slowly with age. The characteristic clinical features include large eyes, nose, lips, and ears, disproportionately long and thick fingers, and the loss of adipose tissue from the upper half of the body. Cardiomegaly and hypertrophy of the periosteum of the phalanges have been described in some cases.

Child, Preschool↗
PubMed1984

One base substitution in IVS-2 causes a beta +-thalassemia phenotype in a Chinese patient.

Two beta-globin genes derived from a Chinese patient with a beta +-thalassemia phenotype have been cloned and sequenced. A four-nucleotide deletion in codon 41 and 42 was found in one of the clones and a C to T substitution at position 654 of IVS-2 was detected in the other clone. The former change, which causes premature termination at codon 59, was found previously in another Chinese patient with homozygous beta 0-thalassemia. The latter change, which has not been reported so far, creates a sequence much like the consensus sequence of the 5' splice site. These results suggest that the new base change found in IVS-2 causes aberrant splicing of the beta-globin mRNA precursor. Thus, this patient is doubly heterozygous for beta 0- and beta +-thalassemia.

Base Sequence↗
PubMed1984

Differential enzyme activities in human esterase D phenotypes.

Red cell ESD activities have been determined in 78 individuals with ESD-1 phenotype, in 94 with ESD2-1 and in 28 with ESD-2 phenotype. The mean activities of these three groups were 276.7, 216.6 and 171.5 expressed as 10(-7) M methylumbelliferone produced/h/g Hb, respectively. The activities associated with a single ESD*1 gene are estimated to be 60% higher than ESD*2.

Alleles↗
PubMed1984

Mitochondrial DNA polymorphism in Japanese. I. Analysis with restriction enzymes of six base pair recognition.

The mitochondrial DNA (mtDNA) from 120 Japanese was analysed with 15 restriction enzymes that recognize six base pairs, of which 11 enzymes showed at least one atypical cleavage pattern. Digestion patterns with Hinc II and Hae II were highly polymorphic. The observed restriction enzyme morphs were classified into 22 types of distinct cleavage patterns. By pairwise comparison of each restriction type, the average number of nucleotide substitutions per nucleotide site (delta) was estimated at 0.00417, which agreed with the values obtained from other human populations in previous studies. There were 11 site gains, of which seven were transitions and four were transversions. Phylogenetic analysis of the present data suggested that the Japanese population conceals a considerably high degree of mtDNA diversity.

Base Composition↗