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Biomedical subjects

M Takeuchi

Publications and source records attributed to M Takeuchi.

At least 757 records · Page 42Linked to original sources
PubMed1989

[Evaluation of left ventricular filling dynamics by pulsed Doppler echocardiography during afterload stress in ischemic heart disease using angiotensin II infusion].

To evaluate cardiac reserve in ischemic heart disease, we simultaneously investigated left ventricular filling parameters using pulsed Doppler echocardiography (PDE) and catheter-obtained hemodynamics before and during afterload stress (angiotensin II test) in 14 patients with ischemic heart disease. The patients were divided into two groups according to their left ventricular function, i.e., mean left ventricular ejection fraction (mLVEF): Group I (n = 7, mLVEF = 65%) and Group II (n = 7, mLVEF = 43%). The peak velocity of rapid filling (R), the peak velocity of atrial contraction (A), the ratio of the two peak velocities (A/R), flow velocity integrals of the rapid filling phase (IR) and atrial contraction phase (IA) were obtained by PDE. Results were as follows: 1. During afterload stress, blood pressure, pulmonary artery wedge pressure, and left ventricular end-diastolic pressures (LVEDP) were elevated in both groups (p less than 0.01). The stroke work index (SWI) increased (p less than 0.01) and the time constant of left ventricular isovolumic pressure decay (T) was unchanged in Group I. SWI did not increase and T was prolonged in Group II (p less than 0.05). delta SWI/delta LVEDP, the ratio of the SWI change to the LVEDP change, during afterload stress was larger in Group I than in Group II (p less than 0.02). 2. Before the infusion of angiotensin II, R and IR were larger in Group I than in Group II. The A/R in Group I was less than that in Group II (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

[EEG analysis of high-dose fentanyl anesthesia--a comparison of rapid sequence anesthesia and the conventional method].

Twenty-one patients who underwent cardiac surgery were assigned to receive high-dose fentanyl rapid sequence anesthesia or conventional high-dose fentanyl anesthesia. In conventional method group, power of delta wave decreased with respect to time. But in rapid sequence group, no decrease was seen until the end of operation. Good maintenance of delta wave in rapid sequence group may be achieved by higher plasma fentanyl concentration and the absence of acute tolerance. In conclusion, high-dose fentanyl rapid sequence anesthesia is a useful method for cardiac surgery.

Adolescent↗
PubMed1989

A handy mirror for self-catheterization in female patients.

We have developed a handy mirror for self-catheterization in female patients. This mirror, as large as a credit card, is made of finely polished stainless steel, and a 12 Fr catheter can be easily attached to or detached from the mirror.

Female↗
PubMed1989

[Autotransplantation of parathyroid glands in thyroid carcinoma surgery and their postoperative function].

Total removal and subsequent autotransplantation of parathyroid glands were carried out in operations for thyroid carcinoma in 25 cases. For the purpose of fine dissection of paratracheal lymph nodes, before thyroidectomy more than 2 parathyroid glands were found and transplanted into greater pectoralis muscle. The patients who underwent surgery were studied for more than one year following operation to determine the short term and long term outcomes of the procedure. None of the patients received prophylactic calcium supplement therapy except for hypocalcemic symptoms. In thirteen patients, the parathyroid function was almost completely restored within 3 weeks without any postoperative substitution therapy, with an obvious surge in the plasma PTH level on 5P.O.D. The serum Ca level started to elevate on 7P.O.D. and recovered to 97.4% of the preoperative value 3 weeks after transplantation. As for the 12 patients who exhibited hypocalcemic symptoms, Ca lactate and hydroxycholecalciferol were administered for only 24.7 and 17.0 days, respectively. Serum levels of Ca and P, as well as the index of bone mineral content, were all within the extremely excellent range even one year after operation. None of the patients was on a substitution regimen. These results suggest that autotransplantation is a valuable alternative for the preservation of the parathyroid function in operations for thyroid carcinoma.

Adult↗
PubMed1989

[BALF cell findings in patients with BOOP, particularly in comparison with UIP].

It is possible to differentiate to some degree to bronchiolitis obliterans organizing pneumonia (BOOP) of unknown etiology from idiopathic usual interstitial pneumonia (UIP) on the basis of clinical symptoms, chest X-ray findings, pulmonary function test and blood gas findings, but in certain patients it can be difficult. Cell findings in bronchoalveolar lavage fluids (BALF) were compared between 8 patients with BOOP and 28 patients with UIP, both diagnosed histologically by open lung biopsy. Findings characteristic of BOOP included (1) an increase in the percentage of lymphocytes, (2) an increase in the percentage of eosinophils, and (3) a decrease in the OKT4+/OKT8+ ratio. These findings provide useful information in making a clinical diagnosis of BOOP and in evaluating proper steroid treatment in patients who unable to undergo open lung biopsy.

Adult↗
PubMed1988

Structure and organization of Marchantia polymorpha chloroplast genome. I. Cloning and gene identification.

We have determined the complete nucleotide sequence of chloroplast DNA from a liverwort, Marchantia polymorpha, using a clone bank of chloroplast DNA fragments. The circular genome consists of 121,024 base-pairs and includes two large inverted repeats (IRA and IRB, each 10,058 base-pairs), a large single-copy region (LSC, 81,095 base-pairs), and a small single-copy region (SSC, 19,813 base-pairs). The nucleotide sequence was analysed with a computer to deduce the entire gene organization, assuming the universal genetic code and the presence of introns in the coding sequences. We detected 136 possible genes. 103 gene products of which are related to known stable RNA or protein molecules. Stable RNA genes for four species of ribosomal RNA and 32 species of tRNA were located, although one of the tRNA genes may be defective. Twenty genes encoding polypeptides involved in photosynthesis and electron transport were identified by comparison with known chloroplast genes. Twenty-five open reading frames (ORFs) show structural similarities to Escherichia coli RNA polymerase subunits, 19 ribosomal proteins and two related proteins. Seven ORFs are comparable with human mitochondrial NADH dehydrogenase genes. A computer-aided homology search predicted possible chloroplast homologues of bacterial proteins; two ORFs for bacterial 4Fe-4S-type ferredoxin, two for distinct subunits of a protein-dependent transport system, one ORF for a component of nitrogenase, and one for an antenna protein of a light-harvesting complex. The other 33 ORFs, consisting of 29 to 2136 codons, remain to be identified, but some of them seem to be conserved in evolution. Detailed information on gene identification is presented in the accompanying papers. We postulated that there were 22 introns in 20 genes (8 tRNA genes and 12 ORFs), which may be classified into the groups I and II found in fungal mitochondrial genes. The structural gene for ribosomal protein S12 is trans-split on the opposite DNA strand. The universal genetic code was confirmed by the substitution pattern of simultaneous codons, and by possible codon recognition of the chloroplast-encoded tRNA molecules, assuming no importation of tRNA molecules from the cytoplasm. The nucleotide residue A or T is preferred at the third position of the codons (G+C, 11.9%) and in intergenic spacers (G+C, 19.5%), resulting in an overall G+C content that is low (28.8%) throughout the liverwort chloroplast genome. Possible gene expression signals such as promoters and terminators for transcription, predicted locations of gene products, and DNA replicative origins are discussed.

Base Sequence↗
PubMed1988

Structure and organization of Marchantia polymorpha chloroplast genome. II. Gene organization of the large single copy region from rps'12 to atpB.

The nucleotide sequence (56,410 base-pairs) of the large single-copy region of chloroplast DNA from the liverwort Marchantia polymorpha has been determined. The sequence starts from one end (JLA) of the large single-copy region and encompasses genes for 21 tRNAs, six ATPase subunits (atpA, atpB, atpE, atpF, atpH and atpI), two photosystem I polypeptides (psaA and psaB), four photosystem II polypeptides (psbA, psbC, psbD and psbG), five ribosomal proteins (rps2, rps4, rps7, rps'12 and rps14), and three RNA polymerase subunits (rpoB, rpoC1 and rpoC2). In addition, we detected 18 open reading frames ranging from 29 to 2136 amino acid residues long, four of which share significant amino acid sequence homology to those of an Escherichia coli malK protein (designated mbpX), human mitochondrial ND2 (ndh2) and ND3 (ndh3) of a respiratory chain NADH dehydrogenase, or a bacterial antenna protein of a light-harvesting complex (lhcA). Sequence analysis suggests that four tRNA genes and six protein genes might be split by introns; they are trnG(UCC), trnK(UUU), trnL(UAA), trnV(UAC), atpF, ndh2, rpoC1, rps'12, ORF135 and ORF167. In the large single-copy region described here, the gene organization deduced is highly conserved with respect to that of higher plants, but an inversion of some 30,000 base-pairs flanked by trnL(CAA) and trnD(GUC) was seen between the liverwort and tobacco chloroplast genomes.

Adenosine Triphosphatases↗
PubMed1988

[Studies on the roles of insulin-like growth factor-1 (IGF-1)/somatomedin C (SMC) during pregnancy].

Studies in human as well as animal experiments have proved that IGF-1/SMC, which shows mitogenic activities in a wide variety of cell types, stimulates growth in vitro and in vivo. The aim of this study was to investigate the roles of IGF-1/SMC on fetal growth during pregnancy by measuring IGF-1/SMC, insulin, C-peptide, human placental lactogen (hPL), and GH and PRL concentrations in maternal and fetal plasma, and by clarifying the changes of IGF receptor in human fetal liver microsomal membranes during pregnancy. Maternal plasma IGF-1/SMC concentrations were not distinguishable from those of nonpregnant women (9.2 +/- 1.7 nmol/l) in the 1st and 2nd trimester of gestation; however, they showed a gradual increase after the 30th week of gestation, reaching 12.7 +/- 5.4 at term. They possessed a significant positive correlation with hPL (r = 0.45, p less than 0.05) and PRL (r = 0.38, p less than 0.05) but not with GH (r = 0.39, NS). On the other hand, IGF-1/SMC in cord plasma could be first detected in the 30th week of gestation, and it increased gradually until term but had no significant correlation with that in maternal plasma. Furthermore, it possessed an intimate correlation with C-peptide (r = 0.30, p less than 0.05) but not with GH or PRL. Additionally, IGF-1/SMC in cord plasma had a positive correlation with birth weight (r = 0.60, p less than 0.005). On the other hand, specific binding of 125I-IGF-1 and -II to liver microsomal membranes which was also displaced by nonlabeled insulin could be detected in human fetuses at various gestational ages. Scatchard analyses indicated that the binding affinity, which was 0.14 +/- 0.05(x 10(9)M-1) in the fetal liver before the 19th week of gestation, increased after the 19th week of gestation (0.58 +/- 0.12); conversely, the binding capacity was lower after the 19th week of gestation (0.15 +/- 0.08 x 10(-12) moles/mg protein) compared with that before the 19th week (0.51 +/- 0.25). These results suggest that (1) plasma IGF-1/SMC might be produced in fetal sites and its regulating mechanism is different from that in maternal sites, and that (2) IGFs might play an important role in human fetal growth and development by its affect via IGF or insulin receptors on the human fetal liver.

C-Peptide↗
PubMed1988

Production of passive cutaneous anaphylaxis (PCA) and reversed PCA by rat IgE antibody in the mouse.

Although IgE antibody is generally characterized as a homocytotropic antibody, it has been well known for some time that mouse IgE antibody causes potent sensitization of rat skin for PCA. The present study clearly shows the reciprocal cross-sensitization of mouse skin with rat IgE molecules. PCA and RPCA were produced by rat IgE antibody in an inbred mouse strain. DS/Shi, though not in C3H/HeShi, C57BL/6JShi and BALB/cCrj strains. Sensitization of DS/Shi mouse skin for PCA with rat IgE antibody was comparable in sensitivity with that of rat skin, but lasted only for a short term in comparison with the long persistence in rat skin.

Animals↗
PubMed1988

Comparative study of the asparagine-linked sugar chains of human erythropoietins purified from urine and the culture medium of recombinant Chinese hamster ovary cells.

The asparagine-linked sugar chains of human erythropoietin produced by recombinant Chinese hamster ovary cells and naturally occurring human urinary erythropoietin were liberated by hydrazinolysis and fractionated by paper electrophoresis, lectin affinity chromatography, and Bio-Gel P-4 column chromatography. Both erythropoietins had three asparagine-linked sugar chains in one molecule, all of which were acidic complex type. Structural analysis of them revealed that the sugar chains from both erythropoietins are quite similar except for sialyl linkage. All sugar chains of erythropoietin produced by recombinant Chinese hamster ovary cells contain only the NeuAc alpha 2----3Gal linkage, while those of human urinary erythropoietin contain the NeuAc alpha 2----6Gal linkage together with the NeuAc alpha 2----3Gal linkage. The major sugar chains were of fucosylated tetraantennary complex type with and without N-acetyllactosamine repeating units in their outer chain moieties in common, and small amounts of 2,4- and 2,6-branched triantennary and biantennary sugar chains were detected. This paper proved, for the first time, that recombinant technique can produce glycoprotein hormone whose carbohydrate structures are common to the major sugar chains of the native one.

Animals↗
PubMed1988

Inhibitory effects of cadmium on in vitro calcification of a clonal osteogenic cell, MC3T3-E1.

To examine an inhibitory mechanism of Cd on bone formation, the effects of Cd on calcification were investigated in a culture of a clonal osteogenic cell line, MC3T3-E1. At 3 days after inoculation, Cd was added to the medium containing 7 mM beta-glycerophosphate, and culture was continued for 8 days. Cd at 1.78 microM and above caused a significant decrease in 45Ca accumulation. The decrease in mineralization by Cd was similar to that in collagen content or alkaline phosphatase (ALP) activity. Histologically, the cell density and the mineralization degree were lower than those of the controls. Ultrastructurally, degenerated cells were observed with undifferentiated cells which had fewer rough-surfaced endoplasmic reticulum and many mitochondria. This suggests that Cd may inhibit the differentiation into osteoblasts as well as the cell function. On the other hand, calcification of cells at 8 days after inoculation was inhibited by Cd at 1.78 microM and above. The decrease in collagen content and ALP activity by Cd was much lower than that in calcification. Cd-treated cells were well differentiated into osteoblasts morphologically, but the mineralization degree was lower than that of the controls. Ultrastructurally, cell damage was not recognized so strongly compared with long-term Cd treatment. The mineralization of osteoblasts was also inhibited by Zn levels which left both collagen content and ALP activity unaffected. From these results, it was suggested that the inhibitory effect of Cd on in vitro calcification of MC3T3-E1 cells may be due to both a depression of cell-mediated calcification and a decrease in physiochemical mineral deposition.

Alkaline Phosphatase↗
PubMed1988

Adsorption of mutagens by refined corn bran.

Refined corn bran (RCB), a dietary fiber derived from the mechanical refining of corn hulls, effectively adsorbed various environmental mutagens. When RCB was added at a concentration of 10 mg/ml to an aqueous solution of dinitropyrene (DNP), 91.6% of the mutagenicity towards Salmonella tester strain TA98 disappeared. Under similar conditions decreases in mutagenicity of DNP using wheat bran and cellulose powder were 58.4% and 43.0%, respectively. The adsorption of DNP to the fibers appeared irreversible since little mutagenicity was recovered by washing the treated fibers with aqueous buffer solutions of various pHs. Even with an organic solvent (methanol: ammonium hydroxide 50:1), only 2/3 of the mutagenicity of DNP was recovered. RCB could similarly adsorb mutagenic heterocyclic amines such as IQ, Trp-P-1, Trp-P-2, Glu-P-1, and Glu-P-2.

Adsorption↗
PubMed1988

The organic matrix of urinary uric acid crystals.

We have demonstrated that urinary uric acid crystals contain an organic matrix within the crystalline boundaries, morphologically similar to that of uric acid stones. Among several glycosaminoglycans in urine, heparan sulfate was almost exclusively identified in this matrix, as in that of uric acid stones. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) showed that several proteins in urine were incorporated in this matrix on a selective basis; two of which were albumin and Tamm-Horsfall mucoprotein. An affinity of uric acid or urate for selective urinary macromolecules in a liquid phase was supposed to be the origin of this matrix. But the proteins in the uric acid stone matrix were not separated by SDS-PAGE. Therefore we could not conclude whether the organic matrix of urinary uric acid crystals is similar to that of uric acid stones.

Crystallization↗
PubMed1988

Physiological role of glucoside 3-dehydrogenase and cytochrome c551 in the sugar oxidizing system of Flavobacterium saccharophilum.

Flavobacterium saccharophilum cytoplasmic membranes contain several cytochromes linked to the respiratory chain. The presence of c-type cytochrome, cytochrome o, and a small amount of a-type cytochrome was proved. Cytochrome c551 was purified to electrophoretic homogeneity by ion-exchange chromatography and gel filtration from a membrane fraction of F. saccharophilum and its properties determined. Cytochrome c551 possessed absorption peaks at 407 nm in the oxidized form, and at 415, 521, 551 nm in the reduced form. The cytochrome c551 had a molecular weight of 15,500 as determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis. Glucoside 3-dehydrogenase of F. saccharophilum reduced the cytochrome c551 with methyl-alpha-D-glucoside, D-glucose, sucrose, or validoxylamine A. When the purified glucoside 3-dehydrogenase was incubated with methyl-alpha-D-glucoside and purified ferricytochrome c551, methyl-alpha-D-3-ketoglucoside was formed as indicated by GC-MS analysis. The addition of a substrate to the membrane fraction caused an increase in the rate of oxygen uptake and an abrupt reduction in cytochrome c551. The electron transfer in the 3-keto sugar forming system may be as follows: sugars----glucoside 3-dehydrogenase----cytochrome c551----cytochrome oxidase----O2. Thus, the electron acceptor of glucoside 3-dehydrogenase is possibly connected to the membrane-bound cytochrome system.

Bacterial Proteins↗
PubMed1988

Bile canalicular contraction in the isolated hepatocyte doublet is related to an increase in cytosolic free calcium ion concentration.

Dynamic contractions of bile canaliculi have been observed in cultured doublet hepatocytes by means of time-lapse cinephotomicrography, and this contractile movement plays an important role in bile secretion. Although details of the mechanism are still unknown, the Ca2+-calmodulin system is believed to play a main role in this mechanism. In this study we measured the intracellular Ca2+ concentration of individual doublet hepatocytes using the Ca2+ indicator "fura 2" and microscopic fluorometry. We also observed the effects of A23187, norepinephrine and epinephrine on bile canalicular contraction and intracellular Ca2+ concentration. After loading 1 mumol/l fura 2 in doublet cells, we added A23187, epinephrine or norepinephrine and then measured the Ca2+ concentration in a given small area in the cytoplasm of individual doublet cell. A23187, norepinephrine and epinephrine caused a prompt increase of the intracellular Ca2+ concentration and also caused bile canalicular contraction. The present study indicates that the sudden increase of intracellular Ca2+ concentration causes bile canalicular contraction through the Ca2+-calmodulin system.

Animals↗