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Biochemical Medicine | 1979

The change in solubility of type I collagen in human uterine cervix in pregnancy at term.

Akira Ito; Kenji Kitamura; Yo Mori; Shun Hirakawa

Abstract Collagen changes in the human uterine cervix in pregnancy at term were investigated. Collagen concentration per dry tissue significantly decreased to about 50% of the control and more than 90% of cervical collagen was insoluble. The insoluble collagen was extracted by pepsin digestion, and about 52% of insoluble collagen in the control and 94% in pregnancy at term were solubilized. In pepsin-soluble fractions, genetically distinct types I and III collagens were isolated by different salt precipitation and identified by ion-exchange chromatography, SDS disc gel electrophoresis, and amino acid composition analysis. Although the rates of pepsin-soluble collagen fraction in control and in pregnancy at term were different, types I III ratios in the fraction were about 2 and 4.7, respectively. The BrCN collagen peptide analyses of pepsin-insoluble residues of control which was about 50% of whole collagen indicated that most of residual collagen was type I. Therefore the ratio of types I III collagen in control of whole collagen approaches the value of 4.7 in pregnancy at term, indicating that the solubility of type I collagen was significantly increased by pregnancy. Both decrease in collagen concentration and increased in type I collagen solubility are important factors to induce the cervical dilatation and effacement in pregnancy at term.


Biochemical Medicine | 1979

Changes in the human uterine cervical collagenase with special reference to cervical ripening

Kenji Kitamura; Akira Ito; Yo Mori; Shun Hirakawa

Abstract Changes in the human cervical collagenase activity of three different types, free active enzyme, a complex with α 2 -macroglobulin, and inactive form activated by 4-aminophenylmercuric acetate, were examined by using fluorescein-labeled collagen and 2,4-dinitrophenyl-Pro-Gln-Gly-Ile-Ala-Gly-Gln- d -Arg. Both active collagenase and the complex of collagenase with α 2 -macroglobulin were found to increase more significantly in pregnancy at term than those in nonpregnant control group. This tendency was also observed in chromatographic profiles on Sephadex G-150. However, the inactive enzyme estimated by activation did not change during the course of pregnancy.


FEBS Letters | 1989

Human recombinant interleukin- 1α increases biosynthesis of collagenase and hyaluronic acid in cultured human chorionic cells

Morimasa Katsura; Akira Ito; Shun Hirakawa; Yo Mori

The influence of human recombinant interleukin‐1α (hrIL‐1) on biosynthesis of collagenase and glycosaminoglycans was investigated with fibroblast‐like cells of human chorionic membrane. hrIL‐1 stimulated cells to produce procollagenase in a dose‐dependent manner. Furthermore, it similarly accelerated both biosynthesis and secretion of hyaluronic acid in chorionic cells, but did not modulate the biosynthesis of sulfated glycosaminoglycans. Therefore, the relative concentration of hyaluronic acid vs total glycosaminoglycans increased significantly. These results are connected with the decrease in tensile strength observed in ruptured fetal membranes. Thus, it is proposed that IL‐1 from effused leukocytes in fetal membranes plays an important role in connective tissue metabolism, especially in premature rupture of membranes with chorioamnionitis.


Biochemical Medicine | 1980

Glycosaminoglycans of human uterine cervix: Heparan sulfate increase with reference to cervical ripening

Kenji Kitamura; Akira Ito; Yo Mori; Shun Hirakawa

Abstract Glycosaminoglycans isolated from nonpregnant and pregnant human cervical uteri were characterized by cellulose-acetate electrophoresis, ion-exchange chromatography, enzymatic digestion, and nitrous acid oxidation. The cervical glycosaminoglycans mainly consisted of dermatan sulfate with hyaluronic acid, chondroitin 4- and 6-sulfate, and heparan sulfate. No effect of pregnancy on the content of glycosaminoglycans in the defatted tissue was found, but the proportion of them in the tissue changed markedly. Thus, a marked increase in heparan sulfate and a decrease in dermatan sulfate was confirmed in the cervix in pregnancy at term.


Journal of Assisted Reproduction and Genetics | 1999

Preimplantation Diagnosis by Fluorescence In Situ Hybridization Using 13-, 16-, 18-, 21-, 22-, X-, and Y-Chromosome Probes

Yutaka Sasabe; K. Paul Katayama; Takayo Nishimura; Akiko Takahashi; Hiroyuki Asakura; Kristen Winchester-Peden; Laura Wise; Yuji Abe; Harumi Kubo; Shun Hirakawa

Purpose:Our purpose was to select the proper chromosomes for preimplantation diagnosis based on aneuploidy distribution in abortuses and to carry out a feasibility study of preimplantation diagnosis for embryos using multiple-probe fluorescence in situ hybridization (FISH) on the selected chromosomes of biopsied blastomeres.Methods:After determining the frequency distribution of aneuploidy found in abortuses, seven chromosomes were selected for FISH probes. Blastomeres were obtained from 33 abnormal or excess embryos. The chromosome complements of both the biopsied blastomeres and the remaining sibling blastomeres in each embryo were determined by FISH and compared to evaluate their preimplantation diagnostic potential.Results:Chromosomes (16, 22, X, Y) and (13, 18, 21) were selected on the basis of the high aneuploid prevalence in abortuses for the former group and the presence of trisomy in the newborn for the latter. Thirty-six (72%) of 50 blastomeres gave signals to permit a diagnosis. Diagnoses made from biopsied blasotmeres were consistent with the diagnoses made from the remaining sibling blastomeres in 18 embryos. In only 2 of 20 cases did the biopsied blastomere diagnosis and the embryo diagnosis not match.Conclusions:If FISH of biopsied blastomere was successful, a preimplantation diagnosis could be made with 10% error. When a combination of chromosome-13, -16, -18, -21, -22, -X, and -Y probes was used, up to 65% of the embryos destined to be aborted could be detected.


Biochemical Medicine | 1984

Effect of dehydroepiandrosterone sulfate on collagenase production in rabbit uterine cervix culture

Akira Ito; Hiroshi Sano; Tomoko Ikeuchi; Katsufumi Sakyo; Shun Hirakawa; Yo Mori

Rabbit uterine cervical explants were found to produce a typical collagenase, latent form, in tissue culture, 4-Aminophenylmercuric acetate and trypsin were potent activators of the enzyme. The enzyme was purified simply in one step of CM-52 cellulose ion-exchange chromatography, and then further characterized. Addition of dehydroepiandrosterone sulfate (DHAS) to culture medium significantly stimulated collagenase production, but DHAS did not directly activate the enzyme. In addition, dehydroepiandrosterone and 17 beta-estradiol, the main metabolites of DHAS in vivo, depressed enzyme production. Our previous result, that increases in cytoplasmic DHAS-binding protein in rabbit uterine cervices parallel the progress of pregnancy, and these results suggest that DHAS might have direct actions toward cervical ripening.


Biochimica et Biophysica Acta | 1981

An alkaline metallo-proteinase in the human uterine cervix and changes in its activity by cervical ripening

Akira Ito; Kenji Kitamura; Shun Hirakawa; Yo Mori

Human uterine cervix at term pregnancy was found to contain an alkaline metallo-proteinase by use of a synthetic substrate, 2,4-dinitrophenyl-L-Pro-L-Gln-Gly-L-Ile-L-Ala-Gly-L-Gln-D-Arg. The enzyme (with a molecular weight of 3.8 . 10(4)) was most active around pH 9.2 toward casein and N alpha-benzoyl-DL-Arg-rho-nitroanilide. [14C]-Gelatin and proteoglycan subunit were also substrates for the enzyme, but [14C]collagen was not. In particular, the enzyme digested gelatin 70-times faster than the novel neutral proteinase in the cervix. Although EDTA was a potent inhibitor, 1,10-phenanthroline, human serum, diisopropylfluorophosphate and elastatinal had no effect on the enzyme. Alkaline proteinase in term pregnant cervices was significantly higher than in non-pregnant ones.


Journal of Human Genetics | 1993

Deletion detection for diagnosis of Duchenne muscular dystrophy in the Japanese population—Comparisom between the polymerase chain reaction and the Southern blot analysis

Susumu Katayama; Naoki Takeshita; Tomone Yano; Tsuneyuki Ubagai; Xiao Jin Qiu; Yukiko Katagiri; Harumi Kubo; Shun Hirakawa

SummaryWe compared the efficacy of the multiplex PCR with that of the cDNA analysis for detection of deletions of the DMD gene in the Japanese patients. Thirty males with DMD from 27 Japanese families were studied by the multiplex PCR, and 24 of them were also investigated by Southern blot analysis. We used five dystrophin cDNA probes for deletion analysis. A total of 19 regions were amplified by the PCR to detect deletions, 9 regions by the method of Chamberlain et al. and another 10 regions by the method of Beggs et al. Deletions were detected in 14 (52%) out of 27 DMD families by the PCR. Southern blot analysis detected deletions in 14 (64%) out of 22 families. Thirteen (93%) of the 14 DMD families with deletions detected by Southern blotting were also confirmed by the multiplex PCR. Provided care is taken in cases where the deletion is limited to a single exon, the multiplex PCR appears to be an efficient and useful alternative to conventional Southern blot analysis for detecting deletions during the prenatal and postnatal diagnosis of DMD.


Gynecologic and Obstetric Investigation | 1984

Collagen and Glycosaminoglycans in the Human Ovarian Capsule with Polycystic Ovarian Disease

Yo Mori; Fujio Hasumi; Akira Ito; Kazuo Shiina; Shun Hirakawa

Connective tissue of human ovarian capsule with polycystic ovarian disease (PCO) is analyzed. The connective tissue components of the capsule were found to mainly consist of type I collagen and acid glycosaminoglycans, such as dermatan sulfate, heparan sulfate, and chondroitin 4- and 6-sulfate. Although their concentration and constituent ratio in the PCO capsule are found to be similar to those in the normal, their total amounts in whole capsule with PCO are higher than in normal ones, because of the enlarged ovary and the thickened capsule. Furthermore, collagen solubility for pepsin in the PCO capsule is larger than that in the normal one. The results suggest that the activation of connective tissue metabolism in the ovarian capsule is one of the factors of anovulation in PCO.


Fetal Diagnosis and Therapy | 1994

Prenatal Diagnosis of Duchenne Muscular Dystrophy by Polymerase Chain Reaction Analysis

Susumu Katayama; Naoki Takeshita; Tomone Yano; Yukiko Katagiri; Yoshiko Shirosita; Harumi Kubo; Shun Hirakawa; Tsuneyuki Ubagai

The efficacy of the polymerase chain reaction (PCR) in the first-trimester prenatal diagnosis of Duchenne muscular dystrophy (DMD) was examined. Twenty-seven fetuses from 26 Japanese pedigrees at risk for DMD were analyzed. PCR-restriction fragment length polymorphism analysis, multiplex PCR, and dinucleotide repeat polymorphism analysis were used. Of 16 males, 11 were determined to be unaffected, 4 were affected, and the remaining 1 was undetermined. Of the 11 female fetuses, 1 was diagnosed as a noncarrier, 4 were carriers, and the carrier status of the remaining 6 was not determined at the option of the patients, although DNA polymorphisms could be detected in those patients. Prenatal diagnosis by PCR analysis was possible in 96% of the fetuses tested (26 of 27).

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Akira Ito

Asahikawa Medical University

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