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A Matsunaga

Publications and source records attributed to A Matsunaga.

At least 19 recordsLinked to original sources
PubMed1997

Mapping of eight testis-specific genes to mouse chromosomes.

We previously identified eight testis-specific genes using antibodies raised against testicular germ cells. They are expressed during spermatogenesis and are presumed to be involved in testicular germ cell differentiation and sperm formation. We have mapped the genomic loci for these testis-specific genes using restriction fragment length variants in interspecific backcross mice. The calmegin gene (Clgn) was mapped to Chr 8. The synaptonemal complex protein gene 1 (Sycp1) probe hybridized with two sequences on different chromosomes; Sycp1-rs2 was mapped to Chr 3, whereas Sycp1-rs3 was mapped to Chr 7. The relaxin-like factor gene (Rlnl) was mapped to Chr 8, and collapsin response mediator protein 1 (Crmp1) was mapped to Chr 5. Three novel genes encoding testis-specific proteins A2 (Tsga2), A8 (Tsga8), and A12 (Tsga12) were mapped to chromosomes 3, X, and 10, respectively.

Animals↗
PubMed1997

Optimization of a polarized photometric detector equipped with a split-type flow cell and its analytical application to oligo-saccharides.

A novel, non-modulated polarimeter called a polarized photometric detector (PPD) was previously described by the authors. The PPD enables the measurement of the optical rotation of chiral compounds as a change in absorbance by placing two linear polarizers on either side of a flow cell of a conventional photometric detector. The present study describes the optimization of the conditions of PPD for highly sensitive detection of saccharides. To maximize the light intensity, the light balancing filter and slit were removed from the detector (Shimadzu model SPD-10AV). These modifications resulted in an approximately 15-fold increase in the incident light intensity when the maximum current was applied to the lamp. When this intense light was transmitted through the polarizers, the signal intensity followed the theoretical equation for phase angles up to around 1 rad. If the energy of the transmitted light was less than 700 mV, however, the baseline noise was too great to determine the chiral analyte accurately. Setting the phase angle between two polarizers at 50 degrees and the detection wavelength at 400 nm provided the most suitable conditions. This detector was applicable for the determinations of oligosaccharides in foodstuffs separated by HPLC using gradient elution.

Flow Injection Analysis↗
PubMed1997

Apolipoprotein E Sendai (arginine 145-->proline): a new variant associated with lipoprotein glomerulopathy.

Lipoprotein glomerulopathy (LPG) is a novel disease characterized by proteinuria, lipoprotein thrombi in the glomeruli, and increased concentration of plasma apolipoprotein (apo) E. It is believed that a genetic disorder of apo E may be present and associated with the disease. Three patients with LPG were examined in this study. The patients' DNA sequences were analyzed, and a nucleotide G to C point mutation in exon 4 of the apo E gene was confirmed in each patient. This missense mutation denotes amino acid substitution of the proline residue for arginine residue at position 145 of apo E. This variant (apo E Sendai) may cause a marked molecular conformational change of the apo E. These findings suggest that a novel variant is etiologically related to LPG.

Aged↗
PubMed1997

[Comparison of echograms by a microscanner and histological findings of the common bile duct, in vitro study].

To confirm the relationship between the layer structure of the common bile duct by a microscanner (MS) and its histological features, we performed a study using the pinning method with needles and catgut. The locations of 67 needles inserted at random depths in 29 slices of the resected common bile duct from 18 patients were confirmed both by a MS and a microscope. The wall of the common bile duct was delineated as a two- (42 points) or three-layer structure (25 points); "low and high" or "high, low, and high echoic layers" from the mucosal side. A fibrotic layer (ss 1) was often (56/67 points, 16/18 patients) seen in the subserosa (ss) containing nerves and vessels larger than 100 mu in diameter. Among the 51 needle echoes demonstrated in the inner hypoechoic layer, 2 were located in the mucosa (m), 12 in the fm, 19 in the af, 17 in the ss 1, and 1 in the fatty layer of the ss (ss 2). Five of the 6 needles in the outer hyperechoic layer were in the ss 2, and 1 was in the pancreatic parenchyma (pa). Four of the 8 needles at the border between the inner hypoechoic layer and the outer hyperechoic layer histologically corresponded to fm, af, ss 1, and pa, respectively, and the other four corresponded to ss 2. From these results, we conclude that the inner hypoechoic layer contains not only m, fm, and af, but also ss 1. Therefore, this should be kept in mind for the preoperative assessment of the depth of bile duct carcinoma by MS.

Bile Duct Neoplasms↗
PubMed1996

Characterization of a novel variant of apolipoprotein E, E2 Fukuoka (Arg-224 --> Gln) in a hyperlipidemic patient with xanthomatosis.

A new variant of apolipoprotein (apo) E, designated apo E2 Fukuoka, was identified in a 54-year-old Japanese woman who suffered from hyperlipoproteinemia (total cholesterol 29.7 mmol/l, triglyceride 12.0 mmol/l, when she was 48-year-old) with the presence of xanthoma in the palms, bones, and ocular fundi, and other sites. Foam-cell macrophages were observed in bone marrow specimens. Analysis of apo E phenotype showed the E3/E2 isoform on isoelectric focusing performed on plasma, but the E3/E3 isoform on restriction-fragment-length polymorphism of the apo E gene. This discrepancy indicated that the apo E had an amino-acid substitution outside of amino-acid residues at 112 and 158. Sequence analysis of the patient's DNA, which was amplified by PCR and subcloned, revealed a single substitution from arginine (CGG) to glutamine (CAG) at residue 224, thereby adding one negatively charged unit to apo E3. Recombinant apo E2 Fukuoka produced in COS-1 cells showed almost the same binding activity to the LDL receptor on human skin fibroblasts as compared with recombinant apo E3. Recombinant apo E2 Fukuoka showed the same heparin binding ability than recombinant apo E3. Findings indicated that apo E2 Fukuoka was not the primary cause of the hyperlipoproteinemia observed in this case.

Apolipoprotein E2↗
PubMed1996

Synthesis, structure and thermodynamic properties of 8-methylguanine-containing oligonucleotides: Z-DNA under physiological salt conditions.

Various oligonucleotides containing 8-methylguanine (m8G) have been synthesized and their structures and thermodynamic properties investigated. Introduction Of M8G into DNA sequences markedly stabilizes the Z conformation under low salt conditions. The hexamer d(CGC[M8G]CG)2 exhibits a CD spectrum characteristic of the Z conformation under physiological salt conditions. The NOE-restrained refinement unequivocally demonstrated that d(CGC[m8G]CG)2 adopts a Z structure with all guanines in the syn conformation. The refined NMR structure is very similar to the Z form crystal structure of d(CGCGCG)2, with a root mean square deviation of 0.6 between the two structures. The contribution of m8G to the stabilization of Z-DNA has been estimated from the mid-point NaCl concentrations for the B-Z transition of various m8G-containing oligomers. The presence of m8G in d(CGC[m8G]CG)2 stabilizes the Z conformation by at least deltaG = -0.8 kcal/mol relative to the unmodified hexamer. The Z conformation was further stabilized by increasing the number of m8Gs incorporated and destabilized by incorporating syn-A or syn-T, found respectively in the (A,T)-containing alternating and non-alternating pyrimidine-purine sequences. The results suggest that the chemically less reactive m8G base is a useful agent for studying molecular interactions of Z-DNA or other DNA structures that incorporate syn-G conformation.

Base Sequence↗
PubMed1996

Identification of two apolipoprotein variants, A-I Karatsu (Tyr 100-->His) and A-I Kurume (His 162-->Gln).

We identified two apolipoprotein (apo) A-I variants, using isoelectric focusing gel electrophoresis: apo A-I Karatsu, which had a relative charge of +1 compared to normal apo A-I4, and apo A-I Kurume, which had a relative charge of -1. Direct sequence analysis of the PCR-amplified DNA from the proband of apo A-I Karatsu revealed a single substitution of tyrosine (TAC) for histidine (CAC) at position 100. Sequence analysis of apo A-I Kurume revealed a single substitution of histidine (CAT) for glutamine (CAG) at position 162. Probands of these two mutants and limited family study showed no accelerated atherosclerosis.

Adult↗
PubMed1996

A cysteine-containing truncated apo A-I variant associated with HDL deficiency.

We identified a 50-year-old Japanese woman with a novel mutation in the apolipoprotein (apo) A-I gene causing high-density lipoprotein (HDL) deficiency. The patient had extremely low HDL cholesterol and apo A-I levels (0.14 mmol/L and 0.8 mg/dL, respectively) but no evidence of coronary heart disease. However, she had bilateral xanthomas of the Achilles tendon, elbow, and knee joint as well as corneal opacities. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of serum followed by immunoblotting revealed that the patient's apo A-I had a lower molecular weight (24,000) than normal apo A-I. A partial gene duplication encompassing 23 nucleotides was found by DNA sequence analysis, resulting in a tandem repeat of bases 333 to 355 from the 5' end of exon 4. This tandem repeat caused a frameshift mutation with premature termination after amino acid 207. The frameshift gives rise to a predicted protein sequence that contains two cysteines. We designated this mutant as apo A-ISasebo. Apo A-ISasebo formed heterodimers with apo A-II and apo E in the patient's plasma and was associated with both the low-density lipoprotein and HDL fractions. The patient's cholesterol esterification rate and lecithin-cholesterol acyltransferase activity were reduced to about 30% of normal, although specific enzyme activity was unaffected, suggesting that it remained functionally normal. In addition, cholesteryl ester transfer activity was reduced to about half of normal. Thus, apo A-ISasebo was associated with complex derangements of lipoprotein metabolism.

Amino Acid Sequence↗
PubMed1996

Identification of two apolipoprotein variants, A-I Kaho (Asp 51-->Val) and A-I Lys 107 deletion.

We have identified two apolipoprotein (apo) A-I variants using isoelectric focusing gel electrophoresis: apo A-I Kaho which has a relative charge of +1 compared to normal apo A-I4, and apo A-I Nanakuma2 which has a relative charge of -1. Sequence analysis of PCR-amplified DNA from the proband of apo A-I Kaho revealed a single substitution of aspartic acid (GAC) for valine (GTC) at residue 51. Sequence analysis of PCR-amplified DNA from the proband of apo A-I Nanakuma2 revealed a three-base (AAG or AGA) deletion between bases 186 and 193 from the 5' end of exon 4 that leads to deletion of Lys 106 or 107. This mutation may be the same as that of apo A-I Marburg or A-I Munster-2 reported by Rall et al. (Rall SC Jr, Weisgraber KH, Mahley RW, Ogawa Y, Fielding CJ, Utermann G, Haas J, Steinmetz A, Menzel HJ, and Assmann G, J Biol Chem, 259: 10063-10070, 1984). Because of its unique sequence between 185 and 193 from the 5' end of exon 4 of apo A-I gene, we could not define whether AAG or AGA is deleted by DNA sequencing.

Adult↗
PubMed1996

[Diagnosis of superficial-type early carcinoma of the gallbladder by endoscopic ultrasonography--comparison with ultrasonography].

The detectability of superficial-type carcinoma of the gallbladder by ultrasonography (US) and endoscopic ultrasonography (EUS) were investigated. Eight patients with such carcinoma of the gallbladder were reviewed. They had undergone both US and EUS previous to surgery. The tumor was detected in 3 patients by US, 2 patients with IIa + IIb-type carcinoma and 1 patient with IIa-type carcinoma. Those lesions were visualized as localized thickening of the gallbladder wall or as broad-based tumor. In 2 patients, lesions were not initially detected by US, but were shown by US after the examination by EUS. The tumor was detected by EUS also in 1 case of IIb + IIa-type carcinoma besides those 3 patients mentioned above. All four of these lesions were visualized as broad-based tumor by EUS. It was difficult to detect pure IIb-type or small IIa-type carcinoma even by EUS. In patients with concomitant acute cholecystitis or gallbladder stone, it was difficult to evaluate the abnormal findings of the gallbladder wall.

Aged↗
PubMed1996

[Ultrasonographic study of rectal carcinoid tumors].

To compare intraluminal ultrasonographic (ILUS) findings with histological findings of rectal carcinoid tumors, 35 patients with rectal carcinoid tumors were reviewed. The results were as follows: 1) The rectal wall was visualized as a seven- or nine-layer structure by means of ILUS in 81% of the patients. 2) The possibility that the thin hyperechoic third layer above the tumor on ILUS corresponds to the muscularis mucosae and fibrointerstitium above the tumor histologically. 3) In cases with relatively high internal echoes, the amount of fibrointerstitium exceeded that of tumor cells histologically. 4) In cases with nonuniform internal echo patterns, tumor cells were separated by thick fibrointerstitium forming nodular nests.

Carcinoid Tumor↗
PubMed1995

GAPO syndrome: report on the first case in Japan.

We studied a 3.5-year-old Japanese boy with growth retardation, alopecia, pseudoanodontia, and bilateral papilledema. He was born of nonconsanguineous parents, but his paternal grandparents were related. From his characteristic physical manifestations, we diagnosed him as the first known case of GAPO syndrome in Japan and perhaps in the Mongoloid race. Our case had prominent dilatation of scalp veins and an audible intracranial bruit. Cranial angiography documented a narrowing of the sigmoid sinuses, with no flow to either jugular vein. We discuss here the relationships between optic atrophy and intracranial vascular changes in this syndrome.

Abnormalities, Multiple↗
PubMed1995

An apolipoprotein CIII marker associated with hypertriglyceridemia in Caucasians also confers increased risk in a west Japanese population.

Polymorphisms and haplotypes at the adjacent apolipoprotein (apo) AI and CIII gene loci were investigated in 61 Japanese patients with triglycerides greater than 350 mg/dl and in 66 unrelated normolipidemic subjects. The polymorphic sites were the SstI site in the apoCIII 3' untranslated region, whose presence has previously been shown to be associated with hypertriglyceridemia (HTG) in Caucasians, and the MspI site in the third intron of the apoAI gene. The frequencies of the SstI minor allele (S2) were 0.48 in HTG patients and 0.25 in normolipidemic subjects (P < 0.00015). The frequencies of the MspI minor allele (M2) were 0.61 in HTG patients and 0.33 in normolipidemic subjects (P < 0.00001). The two polymorphic sites were in strong linkage disequilibrium, and maximum likelihood analysis supported the existence of three of the four possible haplotypes: S1-M1, S1-M2, and S2-M2. Since all S2 alleles were estimated to be present on M2-bearing chromosomes, the HTG-associated S2-M2 haplotype conferred the same approximate relative risk as the S2 allele alone when compared with the other two haplotypes (odds ratio 2.8). This study demonstrates that the S2 allele is a marker for HTG among west Japanese subjects as well as among Caucasians. The results suggest that S2-M2 chromosomes carry HTG susceptibility sequences that predate the separation of the Asian and Caucasian races.

Alleles↗
PubMed1995

Serum glycoproteins and severity of coronary atherosclerosis.

The relation of serum glycoproteins and C-reactive protein (CRP) to severity of coronary atherosclerosis was examined in 133 men and 92 women undergoing coronary angiography. The following serum glycoproteins were determined: alpha 1-antitrypsin, alpha 1-acid glycoprotein, alpha 2-macroglobulin, ceruloplasmin, haptoglobin, fibrinogen, C4b binding protein, and lipoprotein (a) [Lp(a)]. Sex- and age-adjusted levels of alpha 1-antitrypsin, alpha 1-acid glycoproteins, alpha 2-macroglobulin, ceruloplasmin, Lp(a) and CRP were significantly associated with the severity of coronary atherosclerosis as determined by the Gensini score; these associations remained significant even after adjustment for body-mass index, smoking history, hypertension, and total cholesterol, except for Lp(a) (p = 0.075). These findings suggest that certain serum glycoproteins and CRP can serve as independent indicators for the progression of coronary atherosclerosis.

Aged↗
PubMed1995

Familial hypobetalipoproteinemia associated with hypothyroidism.

A 55-year-old Japanese woman with familial hypobetalipoproteinemia associated with hypothyroidism was admitted to the hospital because of orthopnea and congestive heart failure. Thyroid function testing revealed hypothyroidism, but she exhibited low levels of serum cholesterol (111 mg/dl) and apolipoprotein (apo) B (48.5 mg/dl). No abnormal bands were detected with gradient sodium dodecyl sulfate-polyacrylamide gel electrophoresis of very low density lipoprotein, low density lipoprotein and high density lipoprotein followed by immunoblotting with anti apo B polyclonal antibody. In this case, apo B structural abnormality could not be identified.

Female↗
PubMed1995

Effects of fluvastatin, a new inhibitor of HMG-CoA reductase, and niceritrol on serum lipids, lipoproteins and cholesterol ester transfer activity in primary hypercholesterolemic patients.

Effects of a combination therapy of fluvastatin, a new inhibitor of HMG-CoA reductase, and niceritrol on lipid metabolism were investigated measuring a wide range of parameters in 42 patients with primary hypercholesterolemia. After a wash-out period patients were randomly allocated to 1 of the 2 groups, the fluvastatin-preceding group (G-1) and the niceritrol-preceding group (G-2). In G-1 fluvastatin monotherapy (30 mg/day) significantly decreased total cholesterol (TC) and LDL-cholesterol (LDL-C). There was no significant change in HDL-cholesterol (HDL-C), triglyceride (TG) and lipoprotein (a) (Lp(a)). Further effect in HDL-C and TG was observed after the addition of niceritrol (750 mg/day). On the other hand, in G-2, while niceritrol alone (750 mg/day) produced no significant change in TC, LDL-C, HDL-C, TG and Lp(a), the addition of fluvastatin (30 mg/day) reduced TC and LDL-C levels significantly. Cholesterol ester transfer (CET) activity was significantly reduced by niceritrol monotherapy. After the concomitant use of the 2 drugs CET activity was significantly reduced only in G-2. No significant change in lipoprotein lipase and hepatic triglyceride lipase activities were observed in the 2 groups at either point in time. No serious adverse effect was observed in this study. It is concluded that fluvastatin is an effective drug for lowering LDL-cholesterol and causes no adverse alteration in lipid metabolism. Combination with niceritrol at a dose of 750 mg/day dose not appear to augment or attenuate beneficial effects of fluvastatin.

Anticholesteremic Agents↗