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Biomedical subjects

N Matsuo

Publications and source records attributed to N Matsuo.

At least 199 records · Page 11Linked to original sources
PubMed1993

Oxidative damage to mitochondria is mediated by the Ca(2+)-dependent inner-membrane permeability transition.

The ability of O2 metabolites derived from the xanthine-xanthine oxidase system to inhibit mitochondrial function was examined using freshly isolated rat liver mitochondria. Under 2,4-dinitrophenol-uncoupled conditions, mitochondria exposed to free radicals exhibited a significant decrease in O2 consumption supported by NAD(+)-linked substrates, but showed almost no change in O2 consumption in the presence of succinate and ascorbate. Oxidative stress caused the loss of intramitochondrial nicotinamide nucleotides, and addition of NAD+ fully prevented any fall in O2 consumption with NAD(+)-linked substrates. The activity of electron-transfer complex I (NADH oxidase and NADH-cytochrome c oxidoreductase) and the energy-dependent reduction of NAD+ by succinate were unaltered by oxidative stress. Exposure to free radicals also had an uncoupling effect at all three coupling sites. The degree of mitochondrial swelling was closely correlated with the inhibition of State-3 oxidation of site-I substrates and with the increase in State-4 oxidation of succinate. The immunosuppressive agent cyclosporin A completely prevented the mitochondrial damage induced by oxygen free radicals (swelling, Ca2+ release, sucrose trapping, uncoupling and selective inhibition of the mitochondrial respiration of site-I substrates). The same protective effect was found when Ca2+ cycling was prevented, either by chelating Ca2+ with EGTA or by inhibiting Ca2+ reuptake with Ruthenium Red. These findings suggest that the deleterious effect of free radicals on mitochondria in the present experimental system was triggered by the cyclosporin A-sensitive and Ca(2+)-dependent membrane transition, and not by direct impairment of the mitochondrial inner-membrane enzymes.

Adenosine Triphosphate↗
PubMed1993

cDNA isolation and partial gene structure of the human alpha 4(IV) collagen chain.

A novel collagen IV chain, alpha 4(IV), has recently been identified in basement membranes. We describe part of the primary structure of the human alpha 4(IV) polypeptide for the first time, which has been determined by cloning and sequencing of cDNAs encoding 241 amino acid residues of the COL domain and 231 residues of the NC1 domain. We also characterized a genomic DNA fragment containing 4 exons coding for the entire NC1 domain. Among five known alpha chains of collagen IV, the alpha 4(IV) chain is distinct from the other four chains. However, it is more similar to the alpha 2(IV) chain than to the alpha 1(IV), alpha 3(IV) and alpha 5(IV) chains in terms of amino acid sequence homology, domain structure of polypeptides and exon/intron structure of the genes, suggesting the presence of two phylogenetically distinct subclasses of collagen IV alpha chains; one composed of alpha 2 and alpha 4 chains and the other of alpha 1, alpha 3 and alpha 5 chains.

Amino Acid Sequence↗
PubMed1993

Urinary mercury level in Japanese school children: influence of dental amalgam fillings and fish eating habits.

The influence of dental amalgam fillings and fish eating frequency on the urinary mercury (Hg) level was evaluated in 1642 children (ages: 3-18) living in Tokyo. Geometric mean of the urinary Hg level was 1.9 microgram Hg/l and 1.9 micrograms Hg/g creatinine (Cr) for boys and 2.1 micrograms Hg/l and 2.0 micrograms Hg/g Cr for girls. Multiple regression analysis was conducted using: (1) urinary Cr concentration (only in the case of urinary Hg expressed as microgram Hg/l); (2) age; (3) gender; (4) number of dental amalgam fillings; and (5) fish eating frequency as independent variables. As a result, all the variables examined were significant and the explanatory powers (square of multiple correlation coefficient) of these variables were 17 or 7% for urinary Hg expressed as microgram Hg/l or microgram Hg/g Cr, respectively. Number of dental amalgam fillings or fish eating frequency explained only up to 1.5% of the total variance of urinary Hg. Contribution of Cr concentration, age and gender to urinary Hg level is also discussed.

Adolescent↗
PubMed1993

Enzyme reactor for urinary acylcarnitines assay by reversed-phase high-performance liquid chromatography.

An immobilized enzyme reactor, made up acylcarnitine hydrolase, carnitine dehydrogenase and diaphorase in sequence, was developed for the sensitive and selective determination of urinary free and individual acylcarnitines by a reversed-phase high-performance liquid chromatography. A 100-microliter urine sample was directly injected onto the TSKgel ODS 80Ts column and eluted by a step-gradient procedure. The eluent was mixed with the substrate solution of beta-NAD+ (1.0 mmol/l), resazurin (25 mumol/l) and Tris acetate (0.2 mol/l, pH 9.0). The mixture was passed through the immobilized enzyme reactor at 40 degrees C. Acylcarnitines were hydrolyzed and the converted to rezorufin which was measured by monitoring the fluorescence intensity at lambda EX = 560 nm and lambda EM = 580 nm. Free, acetyl-, glutaryl-, propionyl-, butyryl-, isobutyryl-, valeryl- and isovalerylcarnitine were determined within 55 min with detection limits (< 1 mumol/l) and within-run and day-to-day imprecision (C.V. < 6%). Free, acetyl- and isobutyrylcarnitine were found in normal urine. On the other hand, propionylcarnitine was detected in the urine of children with propionic aciduria and methylmalonic aciduria and multiple acylcarnitines were found in the urine of children with glutaric aciduria (type II).

Acetylcarnitine↗
PubMed1993

[CO2US via an implantable port--drug distribution in intraarterial chemotherapy for hepatic tumors and evaluation of effect].

The distribution of blood flow was determined from the distribution of CO2 by US performed during the infusion of CO2 microbubbles via an implantable port (IP-CO2US) in intraarterial chemotherapy for hepatic tumor, and the usefulness of this method in determining tumor vascularity and evaluating the effects of therapy was investigated. A total of 16 patients, 12 of whom had metastatic liver tumor, two hepatocellular carcinoma, one gall bladder carcinoma, and one cholangiocellular carcinoma were studied. The enhanced areas in the liver in 16 patients in whom IP-CO2US was performed a total of 24 times were consistent in all cases with the enhanced areas demonstrated by IP-RI angiography performed a total of 10 times within 10 days, and were also consistent with one exception with the enhanced areas demonstrated by IP-CTA performed 14 times. The tumor detection rate was markedly higher with IP-CO2US than with plain US or IP-DSA, and was similar to that of IP-CTA. Evaluation of the vascularity of individual nodules by IP-CO2US surpassed that by IP-DSA, and was similar to that of IP-CTA. It was demonstrated that blood flow distribution (intrahepatic drug distribution) can be equally well grasped with IP-CO2US, which is a simple and convenient method, as with IP-RI angiography. It was also suggested that IP-CO2US is useful in the evaluation of tumor vascularity and the effect of therapy.

Antineoplastic Agents↗
PubMed1993

[Study on the evaluation of recurrence of HCC and the effect after transcatheter hepatic arterial embolization--fluctuations in AFP values].

To determine the usefulness of alpha-fetoprotein (AFP) in determining recurrence of HCC after interventional angiography (IVA) and to define the relation between AFP and the imaging diagnosis of HCC recurrence, changes in AFP values in 160 patients with hepatocellular carcinoma who were treated by IVA > or = two times were classified into four patterns: A: the AFP value was decreased after the first IVA, increased at recurrence and decreased again after the second IVA; B: the AFP value was unchanged after the first IVA, but increased at recurrence and decreased after the second IVA; C: the AFP value was decreased after the first IVA, but was not increased at recurrence; D: the AFP value showed no change. The frequency of each AFP pattern and the diagnosis of recurrence by AFP were determined. The relation between tumor type and AFP was defined. Pattern A was the most frequently detected. In 62.6%, AFP was increased at recurrence (A and B), and there was a positive correlation between changes in the AFP value and the findings of imaging diagnosis. In another 37.5%, AFP was not increased at recurrence (C and D), and therefore, the diagnosis of HCC recurrence by imaging methods was very important.

Aged↗
PubMed1993

Absent chondrodysplasia punctata in a male with an Xp terminal deletion involving the putative region for CDPX1 locus.

This is a follow-up report on a male patient with a 46,Y,r(X) karyotype. Although he had no clinico-radiological features of X-linked recessive chondrodysplasia punctata (CDPX1), molecular studies revealed an Xp terminal deletion involving the putative region for the CDPX1 locus (PABX-DXS31). We suspect that the absence of CDPX1 may be attributable to the nature of the disease and the extreme short stature of the patient (mean -5.6 S.D.).

Blotting, Southern↗
PubMed1993

Correlation between HPV positivity and state of the p53 gene in cervical carcinoma cell lines.

Human papillomavirus (HPV) infection is clearly associated with cervical carcinomas, yet it is also true that there are cervical carcinomas in which HPV DNA is absent. We examined eight established cell lines derived from cervical carcinomas for the presence of mutations of the p53 antioncogene in relation to the presence of HPV DNA sequences. Of these eight cell lines, seven were positive for HPV DNA and the remaining one was negative for HPV DNA. Single-strand conformation polymorphism analyses revealed a point mutation of the p53 gene in the cell line in which HPV DNA was absent. Sequencing analysis revealed a single-base mutation at codon 273 from CGT to CAT(Arg-->His) and immunocytochemical studies provided evidence that the p53 protein was overexpressed in this cell line. Our observations suggest that the loss of normal p53 gene function may be linked to the oncogenesis of cervical carcinoma.

Adenocarcinoma↗
PubMed1993

Sex chromosome aberrations and stature: deduction of the principal factors involved in the determination of adult height.

Although sex chromosome aberrations are frequently associated with statural changes, the underlying factors have not been clarified. To define the factors leading to the statural changes, we took the following three steps: (1) determination of the mean adult height in nonmosaic Caucasian patients with sex chromosome aberrations reported in the literature (assessment of genetic height potential); (2) assessment of the validity of factors that could influence stature; and (3) correlation of the mean adult height with the effects of specific growth-related factors. The results indicate that the adult height in patients with sex chromosome aberrations may primarily be defined by the dosage effect of pseudoautosomal and Y-specific growth genes, together with the degree of growth disadvantage caused by alteration of the quantity of euchromatic or non-inactivated region.

Adult↗
PubMed1993

Application of multivariate autoregressive modelling for analysing chloride/potassium/bicarbonate relationship in the body.

The authors repeatedly analysed course data of acid-base disturbances accompanying hypochloraemia and/or hypokalaemia by means of multivariate autoregressive modelling. It was found that the regulatory relationship between chloride and bicarbonate is inverse between the following two hypochloraemic hyperbicarbonataemic states: the one induced by chloride depletion and the other induced by CO2 retention. Also, the study revealed an independent role of potassium deficiency in the development of metabolic alkalosis, especially in cases with mineralocorticoid-induced alkalosis. The present approach enabled the authors to solve a long-standing problem, i.e. to differentiate between the roles of chloride and potassium in the development of metabolic alkalosis.

Alkalosis↗
PubMed1993

Polymerase chain reaction analysis of human papillomavirus in adenocarcinoma and adenosquamous carcinoma of the uterine cervix.

Thirty-two cervical adenocarcinomas and adenosquamous carcinomas were examined to search for human papillomaviruses (HPVs) using the polymerase chain reaction system. Human papillomavirus type 16 (HPV16) and type 18 (HPV18) deoxyribonucleic acid was detected in 22% and 16% of these carcinomas, respectively. HPV16 was the most common type in both adenocarcinoma and adenosquamous carcinoma, and the mean age of the HPV negative patients was significantly higher than that of HPV positive patients. There may be an association between HPVs and the development of certain adenocarcinomas and adenosquamous carcinomas of the cervix.

Adenocarcinoma↗
PubMed1993

Photoreceptor outer segments in the aqueous humor of patients with atopic dermatitis and retinal detachment.

We examined the aqueous humor by electron microscopy of four patients with atopic dermatitis and retinal detachment. All the patients had a moderate number of cells in the aqueous humor. Cataract impaired fundus visualization except for one patient with aphakia. A flat retinal detachment involved a wide area detected by echography. The intraocular pressure in the eyes with retinal detachment demonstrated a marked diurnal fluctuation compared with that of the fellow eye. The aqueous cells consisted predominantly of photoreceptor outer segments. This finding does not support the theory that aqueous cells in atopic dermatitis are of inflammatory origin. Photoreceptor outer segments in aqueous humor are indicative of rhegmatogenous retinal detachment in patients with atopic dermatitis.

Adolescent↗
PubMed1993

A mutation in the Pax-6 gene in rat small eye is associated with impaired migration of midbrain crest cells.

The rat small eye strain (rSey) lacks eyes and nose in the homozygote, and is similar to the mouse Sey strain with mutations in the Pax-6 gene. We isolated Pax-6 cDNA clones from an rSey homozygote library, and found an internal deletion of about 600 basepairs in the serine/threonine-rich domain. At the genomic level, a single base (G) insertion in an exon generates an abnormal 5' donor splice site, thereby producing the truncated mRNA. Anterior midbrain crest cells in the homozygous rSey embryos reached the eye rudiments but did not migrate any further to the nasal rudiments, suggesting that the Pax-6 gene is involved in conducting migration of neural crest cells from the anterior midbrain.

Alternative Splicing↗
PubMed1993

[Serum/tissue interleukin-6 concentrations and constitutional abnormalities in 4 patients with cardiac myxoma].

Immunological features and the production of interleukin-6 (IL-6) in 4 patients with cardiac myxoma were studied. The patients' age ranged from 11 years old to 57 years old; all 4 patients were female. Case 1, an 11-year-old female patient with myxoma located in the right ventricle, was considered to be a familial case. Her mother had myxomas in the right and left atrium, and had undergone removal of both tumors 3 years before. Peripheral blood examination revealed various inflammatory parameters in all of these patients. White blood cell (WBC) count was over 8,000/cmm in 3 of the 4 patients, positive CRP was found in 2 patients, IgG was higher than 1,500 mg/dl in 3 patients, positive anti-nuclear antibody was seen in 1 patient, and positive rheumatoid factor was identified in 1 patient. The OKT 4/8 ratio of lymphocyte subpopulation was 4.65 in one patient. The lymphocyte mitogenic response to PHA was increased in 2 patients. Serum IL-6 increased in 3 of 4 patients, and returned to normal within 3 to 4 weeks after operation. The IL-6 concentration in the homogenized sample remarkably increased in all 4 patients. Tumors larger than 4 cm contained higher tissue IL-6 concentrations than those smaller than 2 cm. The cultured myxoma cells produced abundant IL-6 in the culture medium supernatant. We conclude that inflammatory signs and immunological abnormalities are common in patients with large cardiac myxoma, and, in addition, serum IL-6 levels may increase in such patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Local immune response in persistent cervical dysplasia.

OBJECTIVE: To investigate the differences in local immune response between persistent and regressive cervical dysplasia. METHODS: We conducted a quantitative study of Langerhans cells, pan-T cells, and helper-inducer T cells in the subepithelial connective tissue using immunohistochemical techniques with S-100 protein antibody, UCHL1, and OPD4, respectively, in 52 paraffin sections. The subjects were patients with persistent cervical dysplasia and a comparable control group of 46 patients with regressive dysplasia. RESULTS: In the subepithelial stroma, the mean (+/- standard deviation) numbers of S-100- and OPD4-positive cells in the persistent group were 8.6 +/- 8.1 and 84.6 +/- 66.3, respectively, compared with 15.1 +/- 9.4 and 147.0 +/- 67.7, respectively, in the regression group. These data demonstrate a significant reduction of Langerhans cells and helper-inducer T cells (P < .0002 and P < .0001, respectively) with persistent dysplasia. CONCLUSION: The decreased numbers of S-100-positive Langerhans cells and helper-inducer T cells in persistent dysplasia compared to those of regressive dysplasia strongly support a decreased local immune response in persistent cervical dysplasia.

Adult↗
PubMed1992

Mutations in the Pit-1 gene in children with combined pituitary hormone deficiency.

Pit-1 is a pituitary-specific transcription factor that binds to and transactivates promoters of growth hormone and prolactin genes. In three unrelated Japanese children with combined pituitary hormone deficiency, we identified three point mutations in the Pit-1 gene, Pro24Leu, Arg143Gln, and Arg271Trp, located on the major transactivation region, POU-specific domain, and POU-homeodomain, respectively.

Amino Acid Sequence↗