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M Endo

Publications and source records attributed to M Endo.

At least 469 records · Page 26Linked to original sources
PubMed1994

Primary structure and distribution of ryanodine-binding protein isoforms of the bullfrog skeletal muscle.

We have cloned two groups of cDNAs which encode isoforms of ryanodine-binding protein/Ca2+ release channel of the bullfrog skeletal muscle sarcoplasmic reticulum. One of the cDNA groups encodes the protein of 5,037 (or 5,031 with a deletion) amino acids with a molecular weight of 571,262 (or 570,607), which is identified as the alpha-isoform of the ryanodine-binding protein based on the amino acid sequence of three tryptic fragments of the purified protein. The other group of cDNAs encodes the protein of 4,868 amino acids with molecular weight of 553,029, which contains the sequences of three proteolytic fragments derived from the beta-isoform protein. About 70% of the amino acid sequence identity is present between alpha- and beta-isoforms of the bullfrog. The primary structure of the alpha-isoform is highly (80%) homologous to the ryanodine-binding protein cloned from rabbit skeletal muscle (type 1). The beta-isoform, on the other hand, is more than 85% identical with that from the rabbit brain (type 3), while it has only 67% overall identity with type 1. Analyses of RNA from various tissues of the bullfrog demonstrate that the beta-isoform is widely expressed, while the alpha-isoform is expressed mainly in skeletal muscle. A phylogenetic analysis of the ryanodine-binding protein/Ca2+ release channel family suggests that the various types of Ca2+ release channels have evolved from an ancestor gene. Possible differential roles of alpha- and beta-isoforms of ryanodine-binding protein in Ca2+ release mechanisms including skeletal muscle excitation-contraction coupling were discussed.

Animals↗
PubMed1994

Hyaluronate depolymerization activity induced by progesterone in cultured fibroblasts derived from human uterine cervix.

High-molecular-weight [14C]hyaluronate was incubated with cultured fibroblasts from human uterine cervix and skin, and then the depolymerization of the hyaluronate was investigated. [14C]Hyaluronate in the medium of skin fibroblasts was depolymerized into a constant molecular weight (M(r) about 40,000), whereas that of cervix fibroblasts was not depolymerized, irrespective of incubation period. However, when progesterone was added to the medium of cervix fibroblasts, hyaluronate was depolymerized to the same extent as that in skin fibroblasts. The reducing terminal sugar of the depolymerized hyaluronate was N-acetylglucosamine. These results suggest that a hyaluronate-depolymerizing enzyme, endo-beta-N-acetylglucosaminidase, was induced by progesterone in cultured fibroblasts derived from human uterine cervix.

Cells, Cultured↗
PubMed1994

Point mutations and allelic deletion of tumor suppressor gene DCC in human esophageal squamous cell carcinomas and their relation to metastasis.

Since tumor suppressor gene DCC exhibits amino acid sequence homology to the neural cell adhesion molecule, there is a possibility that DCC might be related to tumor metastasis. In the present study, we examined 51 cases of primary esophageal carcinomas with regard to point mutations and loss of the DCC gene. We detected point mutations in two cases by screening using polymerase chain reaction-single strand conformation polymorphism analysis. When we determined the sequences, one case with lymph node metastasis showed an ATG (Met) to ACG (Thr) missense mutation in codon 168. Another case showed a CGA (Arg) to GGA (Gly) mutation in codon 201, which might be a polymorphic change, and two other mutations resulting in no amino acid change. We also examined loss of heterozygosity of the DCC gene. Forty-four of the 51 cases (86%) were informative, and among them 10 cases (23%) showed allelic deletion. The further away the lymph node metastasis was from the primary tumor, the higher the frequency of allelic deletions became. We also found allelic deletions in moderately and poorly differentiated squamous cell carcinomas but not in well differentiated ones. These results indicate that alterations of the DCC gene are related to the degree of lymph node metastasis and the degree of differentiation.

Alleles↗
PubMed1994

Characterization of hydrolysis and transglycosylation by testicular hyaluronidase using ion-spray mass spectrometry.

Various oligosaccharides from hyaluronic acid, which were fluorescence-labeled and blocked by pyridylamination at the reducing terminal, were incubated as substrates or acceptors with bovine testicular hyaluronidase. Fluorescence-labeled reaction products in the reaction mixture were monitored selectively and directly by ion-spray mass spectrometry without chemical derivatization. As a result, several features of the relationship between oligosaccharides, substrates, and testicular hyaluronidase were clarified. When hexasaccharides or larger oligosaccharides having D-glucuronic acid at the nonreducing terminal were used as substrates, they were hydrolyzed sequentially to disaccharides from the nonreducing terminal, and these disaccharides were then transferred to other hexasaccharides. On the other hand, when heptasaccharides or larger oligosaccharides having N-acetyl-D-glucosamine at the nonreducing terminal were used as substrates, trisaccharides were released from the nonreducing terminal, and then also transferred to other hexasaccharides, thus forming nonasaccharides. Thus, the relationship between hydrolysis and transglycosylation reactions with testicular hyaluronidase was characterized using ion-spray mass spectrometry.

Animals↗
PubMed1994

pH dependence of inositol 1,4,5-trisphosphate-induced Ca2+ release in permeabilized smooth muscle cells of the guinea-pig.

1. The dependence on pH of inositol 1,4,5-trisphosphate (IP3)-induced Ca2+ release was studied in saponin-skinned smooth muscle cells from guinea-pig portal vein, using the indicator fura-2 to monitor Ca2+ release. 2. Increasing pH between 6.7 and 7.3 enhanced the rate of IP3-induced Ca2+ release at all the Ca2+ concentrations above 30 nM without changing the bell-shaped dependence of the Ca2+ release rate on Ca2+ concentration with a peak near 300 nM. 3. The ascending limb of the biphasic Ca2+ dependence was shifted slightly toward the lower Ca2+ concentration at pH 7.3, suggesting an increase in the Ca2+ sensitivity of IP3-induced Ca2+ release at the higher pH. 4. With the elevation in pH from 6.7 to 7.3 at 100 nM Ca2+, about 7-fold higher IP3 concentration was required to release half of the Ca2+ in the store within 15 s. This pH-dependent change in the IP3 sensitivity was smaller at 1 microM Ca2+ and was indiscernible in the absence of Ca2+. 5. These results suggest that H+ may inhibit binding of IP3 and Ca2+ to the modulator sites of the Ca2+ release mechanism. However, these effects on the binding sites may not fully explain the complex effect of pH, and there may be pH-dependent step(s) involved in the gating mechanism of IP3 channels. The present study demonstrates the importance of pH as a modulator of IP3-induced Ca2+ release.

Animals↗
PubMed1994

Single-port laparoscopy assisted appendectomy under local pneumoperitoneum condition.

We describe herein a novel, simplified technique of laparoscope-assisted appendectomy under local pneumoperitoneum condition. A 12-mm-outer-diameter laparoscope fitted with a transparent plastic cap is inserted through a single, small, open laparotomy incision. This scope has a 5-mm working channel for insertion of the multifunctional metallic catheter which maintains the local pneumoperitoneum condition. When we have located the inflamed appendix by tracing the tenia of cecum, we use the grasping forceps protruding from the working channel of this laparoscope to grasp its tip or root on the cecum. This allows us to pull the appendix up and out through the small incision and to resect it in the conventional surgical way. This procedure permits the surgeon to perform appendectomy by making only one small incision under spinal anesthesia, and also eliminates development of the intracavitary concomitant diseases.

Appendectomy↗
PubMed1994

An approach to the hepatic hilus with marked fibrosis: a surgical technique for reconstruction of the bile duct with a benign stricture.

It is very difficult to approach the hepatic hilus safely in patients with common and/or hepatic bile duct strictures in which normal tissue has been replaced by scarred tissue with firm fibrous adhesions. In this report, we describe how eight patients with benign strictures of the bile duct underwent an operation which involved dividing the superior mesenteric and portal veins from the lower margin of the pancreas in a dorsal direction using a finger in a tunneling technique. The common bile duct, which was buried in scar tissue, was then explored, while the common and/or proper hepatic arteries in the hepatoduodenal ligament were confirmed, after transsection at the superior margin of the pancreas. Biliary reconstruction was successfully performed after resection of the constricted bile duct in all the patients, none of whom have experienced recurrence from 6 months to 5 years after the operation.

Aged↗
PubMed1994

Twelve years' experience with the St. Jude Medical valve prosthesis.

Since July 1978, 1,284 patients have received the St. Jude Medical prosthesis (425 aortic, 636 mitral, and 223 double aortic-mitral), and the results in these patients were reviewed according to guidelines of the Society of Thoracic Surgeons. Follow-up was complete in 98%. Of 80 late deaths, 29% were valve related. The actuarial survival rate, including operative deaths, at 12 years was 81.7% and 87.1%, respectively, for aortic and mitral valve replacement, and it was 82.6% at 11 years after double valve replacement. All patients were anticoagulated with warfarin to maintain the thrombotest value between 10% and 25%, which is equivalent to between 2.8 and 1.6 times the control according to the international normalized ratio of the prothrombin time. The linearized rate of complication for aortic, mitral, and double valve replacement, respectively (expressed as the percent per patient-year), was as follows: structural deterioration, 0; non-structural dysfunction, 0.16, 0.30, and 0.20; valve thrombosis, 0.05, 0.09, and 0; thromboembolism, 1.35, 1.63, and 0.79; anticoagulant-related hemorrhage, 0.10, 0.18, and 0.10; and prosthetic valve endocarditis, 0.21, 0.06, and 0.20. Reoperation was performed in 16 patients. The freedom from reoperation rate at 12 years was 99.5% and 98.0% for aortic and mitral valve replacement, respectively, and it was 99.1% at 11 years for double valve replacement. Thus, during the 12-year follow-up in patient who received the St. Jude Medical prosthesis, the valve performed satisfactorily and with an acceptable risk of late complication even though patients were anticoagulated using a lower dose of warfarin.

Actuarial Analysis↗
PubMed1994

Long-term results of surgical treatment in infants with total colonic aganglionosis.

The authors describe the long-term results of the surgical treatment of total colonic aganglionosis (TCA) in nine boys who have been treated since 1975. The principal operative procedure was endorectal pull-through of the ganglionic ileum, with the aganglionic colon as an onlay patch. The procedure was employed in five infants, using the right or left colon. Ileorectostomy with an onlay patch was used in two patients; ileoanostomy without the patch was used in two. The distal end of the pulled-through ileum was, on average, 39 cm from the ileocecal junction. The average follow-up period was 11.0 years. Diarrhea and distension were temporary after the pull-through, and all patients ultimately tolerated normal feeding. Considering the variation in operative techniques, we were unable to demonstrate any advantage of one procedure over another. Z scores for height and weight at the last follow-up examination correlated with the weight gain before the definitive surgery and inversely correlated with the length of resected distal ileum at the time of operation.

Anal Canal↗
PubMed1994

Recto-vagino-vestibuloplasty using a vagino-colonic flap with double colonic implantation for rectocloacal fistula.

This technique was devised to obtain a good cosmetic appearance of the perineum and a functional neovagina, without any need for a dilator, by using a vaginocolonic flap marsupialized to the perineum and by creating a vestibule with noncornifying squamous epithelium. The technique was used to treat a 2 year old girl who had a single small orifice in the upper part of a featureless perineum, with a high-confluence rectocloacal fistula between a short urethra and double vagina, which was separated by a septum. A long inverted U-shaped flap at the posterior wall of the vagina was reversed to become the anterior wall of the distal vagina. The urogenital sinus (UGS) was preserved to serve as the urethra. The colon distal to the colostomy was divided into two loops; a segment of the distal loop was opened and trimmed to form a flap, and served as the posterior wall of the distal vagina. The proximal segment was pulled down to become the rectum. To construct the vestibule, a vertical midline incision was made from the fused labia minora to the perineum, cutting back the UGS. The anterior wall of the vagina, which was pulled through just behind the UGS, was divided vertically and sutured around the opened UGS and the suitably prepared labia minora. The posterior wall, which consisted of the colonic flap, was sutured to the incised perineal skin, creating a posterior commissure. At present, 2 1/2 years after the repair, the patient is dry between completely continent urinations and has little vaginal discharge.(ABSTRACT TRUNCATED AT 250 WORDS)

Child, Preschool↗
PubMed1994

Analysis of glycosaminoglycans by high-performance liquid chromatography.

Glycosaminoglycan chains were liberated from proteoglycan by successive digestion with protease and endo-beta-xylosidase. The glycosaminoglycan chains were then labeled with a fluorescent reagent, 2-aminopyridine, by reductive amination. The resulting pyridylamino-glycosaminoglycans, including hyaluronic acid, heparan sulfate, chondroitin sulfate/dermatan sulfate and heparin, were separated by ion-exchange high-performance liquid chromatography using a TSK gel SAX analytical column with a limit of sensitivity in the picomol range. With the combined use of a dermatan sulfate-degrading enzyme, chondroitinase B, chondroitin sulfate and dermatan sulfate were identified and quantified, separately. About 50 mg of wet animal tissue was enough for analysis of each glycosaminoglycan with satisfactory results. This method facilitates rapid separation and microanalysis of glycosaminoglycans.

Animals↗
PubMed1994

A method for determination of galactosyltransferase I activity synthesizing the proteoglycan linkage region.

An assay method was devised for measuring the activity of galactosyltransferase I (UDP-D-galactose:D-xylose galactosyltransferase), which is one of the enzymes synthesizing the linkage region between the core protein and glycosaminoglycan chains of proteoglycan. For this method, the reaction mixture contained a fluorescent substrate, 4-methylumbelliferyl-beta-D-xyloside as an acceptor, UDP-galactose as a donor and D-galactal as a competitive inhibitor of endogenous beta-galactosidase in the enzyme solution. The reaction mixture was incubated at 37 degrees C with enzyme solution prepared from an extract of cultured cells, and galactosyl-xylosyl-4-methylumbelliferone was produced as a reaction product. Measurement of galactosyltransferase I activity was performed by separation and quantitative analysis of this reaction product using high-performance liquid chromatography. Utilizing this method, easier and more sensitive detection of galactosyltransferase I activity in a cell-free system became possible. Application of the method revealed that cultured human skin fibroblasts contained galactosyltransferase I activity.

Binding, Competitive↗
PubMed1994

Coronary artery bypass grafting in chronic renal dialysis patients: intensive perioperative dialysis and extensive usage of arterial grafts.

Twenty-three chronic renal dialysis patients underwent coronary artery bypass grafting (CABG). Eighteen patients were maintained on hemodialysis and 5 patients received continuous ambulatory peritoneal dialysis. Eighteen patients (78%) had triple vessel disease or left main disease. The mean number of revascularized vessels was 2.2 +/- 0.8, and the graft materials used were left internal thoracic artery (21), right internal thoracic artery (7), right gastroepiploic artery (7), and saphenous vein (15). The utilization index of arterial grafts (percentage of patients with at least one arterial graft) was 95.7%. Intraoperative hemodialysis (HD) was performed during cardiopulmonary bypass in all patients. In 17 patients on HD preoperatively, peritoneal dialysis (PD) was initiated immediately after the operation, and maintained until the hemodynamics stabilized sufficiently to resume HD (mean: 5.7 +/- 3.4 days after operation). In the patients with a gastroepiploic artery pedicle, PD could be established without leakage of dialysis fluid into the pericardial cavity by means of making a smaller hole in the diaphragm, passing the skeletonized portion of the graft through the hole and sealing the hole using fibrin glue. There were no hospital deaths. Angiography revealed an overall graft patency rate of 95.8% (46/48), and all arterial grafts were patent. There were 4 late deaths (1 cardiac, 3 cerebral hemorrhage). In conclusion, CABG can be accomplished in chronic renal dialysis patients with excellent early and long-term results through an intensive perioperative dialysis program and extensive usage of arterial grafts.

Adult↗
PubMed1994

A novel oligosaccharide, xylosyl beta 1-4xylosyl beta 1-(4-methylumbelliferone), synthesized by cultured human skin fibroblasts in the presence of 4-methylumbelliferyl-beta-D-xyloside.

4-Methylumbelliferyl-beta-D-xyloside (Xyl-MU) was added to the medium of cultured human skin fibroblasts. After incubation, the culture medium was pooled, concentrated with a lyophilizer, and dialyzed against distilled water. Then the Xyl-MU derivatives in the diffusate were purified by gel-filtration and HPLC. A novel Xyl-MU derivative was obtained, in addition to the previously reported Xyl-MU derivatives, Xyl-MU-induced glycosaminoglycan (GAG-MU), SA-Gal-Xyl-MU, GlcA-Xyl-MU, Gal-Gal-Xyl-MU, and Gal-Xyl-MU. This Xyl-MU derivative was subjected to carbohydrate composition analysis, enzyme digestion, Smith degradation and ion-spray mass spectrometric analysis, and the results indicated that it was Xyl beta 1-4Xyl beta 1-MU. Although the quantity of Xyl beta 1-4Xyl beta 1-MU synthesized by human skin fibroblasts increased with incubation time, its production was independent of that of the GAG-MU. Xyl-Xyl-MU is different from the intermediates in the regular pathway of GAG-MU biosynthesis initiated by added Xyl-MU, posing an interesting question as to its significance in GAG biosynthesis.

Carbohydrate Sequence↗
PubMed1994

Reproducibility of magnetic resonance spectroscopy in patients undergoing dialysis and evaluation of the therapeutic response of tumors.

RATIONALE AND OBJECTIVES: The reproducibility of repeated magnetic resonance (MR) spectroscopy was studied in patients undergoing dialysis and treatment of a variety of malignant tumors. METHODS: Localized MR spectra were obtained using a 1.5-T system by image-selected in vivo spectroscopy. Total metabolite signal was integrated between phosphomonoester and beta-adenosine triphosphate resonance. We termed this measurement AREA. RESULTS: Intrapatient variability was evaluated on repeated thigh muscle spectroscopy for 10 patients. Sequential spectra of 10 malignant tumors of the extremities were analyzed and compared with the histology of surgical specimens in seven patients. Intrapatient variability in AREA was calculated as 14.0%. The extent of necrosis and AREA ratio (definition: AREA post-therapy/AREA pretherapy) were as follows; 6.1% in > 90% necrosis, 43% in 50% to 90% necrosis, and 79% in < 50% necrosis. CONCLUSIONS: Localized MR spectra are fairly reproducible and may relate to treatment efficacy.

Adolescent↗