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Biomedical subjects

A Moriyama

Publications and source records attributed to A Moriyama.

At least 73 records · Page 4Linked to original sources
PubMed1993

Study on dermatomes by means of selective lumbar spinal nerve block.

Regions of sensory impairment of 71 patients in 86 lumbar spinal nerve blocks (L4 19 cases, L5 41 cases, S1 26 cases) were determined by the writing brush method. Distinctive regions included the medial side of the lower leg, the side of the first dorsal digit, and the side of the fifth digit respectively of the L4 (88%), L5 (82%) and S1 (83%) spinal nerves without 100% matching because of displacement of one spinal segment by the furcal nerve. A band-like impaired zone from the proximal to the periphery appeared in 42%, 44%, and 92%, respectively, of the L4, L5, and S1 blocks. The marked difference between L4, L5, and S1 may be caused by the diversity of the dorsal rami of the spinal nerves and double control by the lateral cutaneous nerve of the thigh.

Afferent Pathways↗
PubMed1993

Solubilization and reconstitution of high- and low-affinity Na(+)-dependent neutral L-alpha-amino acid transporters from rabbit small intestine.

High- and low-affinity Na(+)-dependent neutral L-alpha-amino acid transporters were solubilized with 0.25% octaethylene glycol dodecyl ether (C12E8) after removal of the proteins from the brush-border membrane vesicles with 2% CHAPS and 4 M urea. When the CHAPS-insoluble protein was treated with papain before its solubilization with C12E8, a substantial amount of protein was removed without any decrease of the transport activities. The solubilized transporters were reconstituted into proteoliposomes after removal of C12E8 with Bio-Beads SM2. Several parameters proved to be important for optimal reconstitution efficiency: (a) the type of detergent, and (b) the phospholipid/protein and detergent/protein ratio during reconstitution, and (c) the salt concentration during reconstitution. Reconstituted proteoliposomes showed rapid uptake of neutral L-alpha-amino acids but not imino acid, basic or acidic amino acids driven by an electrochemical potential of Na+ (out > in). The uptakes under low- and high-substrate condition were further augmented by an artificial membrane potential introduced by K+ diffusion via valinomycin (negative interior). Kinetic analysis revealed that both the brush-border membranes and the solubilized fraction involved two carrier-mediated pathways for alanine transport. The kinetic parameters were determined by curve fitting with a computer to be Kt1 = 0.28 mM (0.21 mM) and Kt2 = 43.2 mM (28.4 mM), respectively (those with brush-border membrane vesicles in parentheses). Studies on the specific activities for transport of individual amino acids under low or high substrate concentration and the cross-inhibitory effects of various amino acids on alanine uptake (low concentration) revealed that these transporters possess broad specificity for neutral L-alpha-amino acids.

Alanine↗
PubMed1993

Changes of sagittal-plane ankle motion and ground reaction force (fore-aft shear) in normal children aged four to 10 years.

The authors investigated the changes in ankle-joint kinematics and ground reaction force during gait in normal children aged four to 10 years. Dorsiflexion of the ankle joint became slower and well controlled from early to mid stance phase with age. The main changes were found at about five years of age. The peak for the fore-aft shear component of the ground reaction force in the deceleration phase occurred later, and was noted during dorsiflexion. However, the peak for plantar flexion, plantar flexion angular velocity and the fore-aft shear component of ground reaction force (all seen during the acceleration phase) did not change significantly with age. These findings appear to be related to maturation of the ankle plantar flexors.

Age Factors↗
PubMed1992

A novel glial growth inhibitory factor, gliostatin, derived from neurofibroma.

Neurofibroma tissue was investigated for the presence of glial growth modulators that would suppress the proliferation of glial cells. A novel endogenous polypeptide inhibitor of proliferation and DNA synthesis in glial cells, gliostatin, was purified from the extracts of neurofibroma by a procedure comprising dye and anion-exchange column chromatography, and HPLC. A monoclonal antibody raised against partially purified gliostatin showed no cross-reactivity with known cytokines, but adsorbed the growth inhibitory activity of gliostatin and immunochemically visualized the putative gliostatin bands on western blot analyses. Although the product showed an apparent M(r) of 100,000 accompanied by an inhibitory activity on gel filtration column chromatography, it migrated at a lower apparent M(r) of 50,000 under the reducing conditions on western blotting, indicating that a homodimeric structure of native gliostatin consisted of 50-kDa subcomponents. Gliostatin was a potent growth inhibitor acting at nanomolar concentrations against all glial tumor cells and glia maturation factor-stimulated astroblasts, but not neuronal cells.

Animals↗
PubMed1990

Effective pretreatment by cysteine proteinase inhibitor for improved analysis of protein components of trematodes on SDS-PAGE.

Since Fasciola sp. contained proteolytic enzyme(s), it was confirmed that degradation took place in protein components in extracts of the liver flukes, which resulted in lack of clarity of sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). Degradation was shown to occur mostly during a heating process of the extract samples. The proteolytic activity in the extracts was completely blocked and electrophoretic patterns were improved only by the use of cysteine proteinase inhibitor N-[N-(L-3-trans-carboxyoxiran-2-carbonyl)-L-leucyl]-agmatine (E-64). Great improvement was also noted in electrophoretic patterns of the extracts of other trematodes, such as Paragonimus westermani, P. miyazakii and Clonorchis sinesis, when their extracts were treated with E-64.

Animals↗
PubMed1990

A novel diisopropylphosphofluoridate-sensitive phenylalanine arylamidase in human liver.

A diisopropylphosphofluoridate-sensitive (DFP-sensitive) arylamidase, which preferentially hydrolyzed Phe-p-nitroanilide (Phe-pNA), was purified from a crude extract of human liver by conventional chromatographic techniques. The purified enzyme gave a single band on SDS-polyacrylamide gel electrophoresis. The molecular weight of the enzyme was estimated to be 58,000 by SDS-polyacrylamide gel electrophoresis and 200,000 by chromatography on a column of Sephacryl S-300, suggesting that the enzyme is a trimer or a tetramer. The enzyme was inactivated in proportion to the amount of [3H]DFP incorporated with a [3H]DFP/subunit (58,000) molar ratio of 1.04. The data indicate that the enzyme belongs to the serine protease family.

Amino Acids↗
PubMed1989

An enzyme immunoassay of slow moving protease (SMP) in human gastric mucosa.

A two-site enzyme immunoassay for slow moving protease (SMP) of human gastric mucosa has been developed. The detection limit of SMP was 50 pg/tube and the optimal assay range was 0.5 to 50 ng/tube. This assay system made it possible to measure a trace amount of gastric mucosal SMP in endoscopic biopsy-specimens. Mean gastric mucosal SMP contents of the antrum, the angles, and the distal and proximal corpuses were 4.5, 3.7, 2.6, and 2.5 micrograms/mg protein, respectively. The antral mucosa contained a larger amount of SMP than the gastric mucosa of other area. The present enzyme immunoassay system is sufficiently sensitive for the clinical study of SMP in gastrointestinal tract.

Electrophoresis, Polyacrylamide Gel↗
PubMed1989

Aminopeptidase M from human liver. I. Solubilization, purification, and some properties of the enzyme.

Aminopeptidase M [EC 3.4.11.2] was purified 772-fold to homogeneity from the microsomal fraction of human liver, with a yield of 18.9%, by a combination of solubilization with 0.5% Triton X-100 and then 1 M urea and chromatography on columns of DEAE-cellulose, hydroxylapatite, Butyl-Toyopearl, and Sephacryl S-300. The purified enzyme had a molecular weight of 140,000 by SDS-polyacrylamide gel electrophoresis and of 280,000 by gel filtration on a column of TSK gel 2000 SW. It was reconstituted into proteoliposomes with asolectin, showing its amphiphilic nature. The aminopeptidase M from liver was found to be efficiently inhibited by bile acids. The enzyme was almost completely inhibited by chenodeoxycholic acid and 70-90% inhibited by cholic acid at a concentration of 6 mM. The extent of inhibition by conjugated and unconjugated bile acids was in the order: unconjugated greater than glycoconjugated greater than tauroconjugated bile acid, independent of the nature of the substrates used. The inhibition by the various bile acids was totally reversible. Further, it was immunochemically revealed that a considerable amount of liver aminopeptidase M was released into the bile duct. The role of the aminopeptidase M on the bile canalicular membrane and of the enzyme released in the bile duct is discussed in relation to the effects of bile acids.

Amino Acids↗
PubMed1989

Aminopeptidase M from human liver. II. Kinetic analysis of inhibition of the enzyme by bile acids.

The mechanism of inhibition of aminopeptidase M by bile acids was analyzed by application of the specific velocity plot that was introduced by Baici [Eur. J. Biochem. 119, 9-14 (1981)]. Kinetic studies with three bile acids (cholic acid, deoxycholic acid, and chenodeoxycholic acid) and three substrates (Leu-Met, Leu-Gly, and Leu-pNA) showed that the inhibition constants Ki for the bile acids were appreciably different from each other, but that the Ki for each was not affected by the substrates used, being 0.89-1.03 mM for cholic acid, 0.42-0.66 mM for deoxycholic acid, and 0.24-0.31 mM for chenodeoxycholic acid. The values of the kinetic coefficient alpha [(apparent Ks in the presence of inhibitor)/Ks] for cholic acid with Leu-Met and Leu-Gly were 9.0 and 2.5, respectively. These values were very similar to those for chenodeoxycholic acid (7.0 and 2.7) but smaller than those for deoxycholic acid (21 and 11). The values of the other kinetic coefficient beta [(apparent kp in the presence of inhibitor)/kp] were 0 except in the case of the combinations of Leu-Gly with cholic acid (0.33) and Leu-Gly with chenodeoxycholic acid (0.13). On the basis of these kinetic parameters, the inhibitions by bile acids were classified into 4 types: competitive-noncompetitive linear mixed type (1 less than alpha less than infinity, beta = 0), noncompetitive-uncompetitive linear mixed type (0 less than alpha less than 1, beta = 0), pure noncompetitive type (alpha = 1, beta = 0), and hyperbolic mixed type (1 less than alpha less than infinity, 0 less than beta less than 1).(ABSTRACT TRUNCATED AT 250 WORDS)

Aminopeptidases↗
PubMed1989

Assessment of cardiopulmonary baroreflex function in hypertensive and normotensive subjects with or without hypertensive relatives.

1. To investigate whether cardiopulmonary baroreflex control contributes to the pathogenesis and progression of hypertension, we have evaluated the function of the cardiopulmonary baroreflex in 22 patients with essential hypertension and in 17 volunteers with normotension. The normotensive group consisted of 8 subjects with a family history of hypertension and nine with no family history. 2. Forearm vascular resistance (FVR) and central venous pressure (CVP) were measured under control conditions when -10 mmHg lower body negative pressure was applied; the cardiopulmonary slope (CPS = delta FVR/delta CVP) was calculated as an index of the cardiopulmonary baroreflex function. 3. CPS was significantly higher in hypertensives (6.0 +/- 3.93 [s.d.], P less than 0.01) and also tended to be higher in normotensives with a family history of hypertension (3.9 +/- 3.53, P less than 0.05), compared with normotensives without a family history of hypertension (1.7 +/- 0.88). 4. When the hypertensives were divided into two groups, depending on whether CPS was greater or less than 6.0 units, cardiac wall thickness (20 +/- 1.6 mm vs 23 +/- 3.2 mm, P less than 0.05) and the renal vascular resistance (20.9 +/- 6.52 units vs 28.9 +/- 7.32 units, P less than 0.05) were both significantly higher in the Low CPS group. 5. These findings suggest that cardiopulmonary baroreflex function was augmented even in normotensive subjects with hypertensive relatives, as compared with those without hypertensive subjects. Furthermore, cardiopulmonary baroreflex function was augmented in the early stages of hypertension and diminished further with increasing severity.

Adult↗
PubMed1989

A sensitive enzyme immunoassay system of rat epidermal growth factor in biological fluids and tissue extracts.

Rat epidermal growth factor was purified from rat submandibular glands to obtain specific antiserum for the establishment of an immunoassay system. Purified rat epidermal growth factor showed a single peak on reverse phase HPLC and a single band on sodium dodecyl sulphate polyacrylamide gel electrophoresis at mol wt 5100 in the presence of 2-mercaptoethanol and at mol wt 41,000 in the absence of 2-mercaptoethanol. Antibody against rat epidermal growth factor showed cross-reactivities with mouse and human epidermal growth factors on soft agar-double immunodiffusion test. The established sandwich enzyme immunoassay for rat epidermal growth factor had a high sensitivity (500 fg/tube), which made it possible to measure minute amounts of endogenous rat epidermal growth factor without pretreatment. Physiological concentrations of rat epidermal growth factor in rat biological fluids and tissues were determined. Species differences in physiological distributions of epidermal growth factor are discussed.

Animals↗
PubMed1988

Porcine muscle prolyl endopeptidase: limited proteolysis of tryptic peptides from hemoglobin beta-chains at prolyl and alanyl bonds.

Tryptic peptides from hemoglobin (Hb) beta-chains were used as model substrates for limited proteolysis by prolyl endopeptidase (EC 3.4.21.26) from porcine muscle. From the physicochemical and enzymatic properties of prolyl endopeptidase the conditions for routine digestion were established as follows: the molar ratio of enzyme to substrate was 1 to 100, and the reaction was carried out in sodium phosphate buffer (pH 6.4) at 37 degrees C for 4 h. Under these conditions the peptide bonds on the carboxyl terminal sides of proline and alanine residues in the tryptic peptides from Hb beta-chains (with Mr values of less than 2100) were hydrolyzed by the enzyme with the exception of the amino terminal alanyl bond and aminoacyl alanyl bond. In addition, one of five seryl bonds was cleaved by the enzyme. However, the Hb beta-chain itself, Mr 16,600, and its two CNBr-peptides with Mr 10,200 and Mr 6400, respectively, were not hydrolyzed. Under the same conditions a prolyl bond in oxidized B-chains of insulin, Mr 3400, was partially digested, and an alanyl bond was not hydrolyzed. The data indicate that the prolyl endopeptidase is useful for the limited proteolysis of peptides with relative masses of less than 3000 at both prolyl and alanyl bonds.

Alanine↗
PubMed1988

Partial purification of alanine carrier from rabbit small intestine brush border membrane and its functional reconstitution into proteoliposomes.

An alanine transport carrier was partially purified from brush border membranes of rabbit small intestine. The alanine carrier activity was not solubilized with 0.4% deoxycholate but recovered in the detergent-insoluble fraction. The detergent-insoluble proteins were reconstituted into proteoliposomes with soybean phospholipids. The reconstituted proteoliposomes were capable of uptake of alanine driven by an electrochemical potential of Na+. The initial rate of alanine uptake into the proteoliposomes was 90 pmoles/mg protein/sec, which was 15-fold higher than that observed with the native membrane vesicles. The uptake of alanine was effectively suppressed by various neutral amino acids but not by either cationic or anionic amino acids.

Amino Acid Transport Systems↗
PubMed1988

Porcine muscle prolyl endopeptidase and its endogenous substrates.

Prolyl endopeptidase [EC 3.4.21.26] was purified 4,675-fold with a yield of 26.3% from porcine muscle. The purified enzyme was shown to be very similar to the liver enzyme with respect to its molecular weight (72,000-74,000), antigenicity, substrate specificity, and susceptibility to protease inhibitors. Among several bioactive peptides, angiotensins I, II, and III had the lowest Km of 0.6 to 3 microM with the lowest kcat of 0.19 to 0.85 s-1, while thyrotropin-releasing hormone had the highest Km of 98 microM with the highest kcat of 14.4 s-1. Interestingly, mastoparan was hydrolyzed at alanyl bonds, but insulin was only slightly hydrolyzed and glucagon was not hydrolyzed although the latter two peptides contain prolyl and/or alanyl bonds. Muscle prolyl endopeptidase failed to hydrolyze proteins with high molecular weight such as albumin, immunoglobulin G, elastin, collagen, and muscle soluble and insoluble proteins. However, 8 of 14 peptides with molecular weights lower than 3,000, which were isolated from muscle extract, were digested by this enzyme, and they were proved to contain prolyl and/or alanyl residues in their molecules. The data suggest that they are probable endogenous substrates for prolyl endopeptidase.

Amino Acid Sequence↗
PubMed1987

An enzyme immunoassay for pepsinogen II(PGII): chronological changes in serum PGII concentrations.

A new two-site enzyme immunoassay for pepsinogen II(PGII) has been developed. The detection limit of PGII was 0.15 ng/ml (15 pg/tube) and the optimal assay range was 1.5 to 150 ng/ml (150 pg to 15 ng/tube). Mean serum PGII concentrations in normal males and females were 17.2 and 14.6 ng/ml, respectively. The chronological analysis among 5 age groups from 20 to 69 yr, males and females together, revealed that the serum level was low (11.9 ng/ml) between 20-39 yr, gradually increased from 40 yr of age and attained the maximum (22.5 ng/ml) in the 50-yr group. Total gastrectomy markedly lowered the serum level to 1.9 ng/ml, suggesting that the majority of PGII in serum was derived from the gastric mucosa. This assay makes it possible to measure trace amounts of PGII derived from extragastric as well as gastroduodenal tissues.

Adult↗