Biomedical subjects

T Miyake

Publications and source records attributed to T Miyake.

At least 235 records · Page 13Linked to original sources

PubMed1990

Impaired development of mammary glands in scorbutic rats unable to synthesize ascorbic acid.

The effects of ascorbic acid (AsA)-deficiency on the development of mammary glands were investigated using mutant rats (osteogenic disorder syndrome rats; ODS rats) with hereditary inability to synthesize AsA. Female ODS rats of 21 days old were castrated and divided into two groups. One group was given AsA in their drinking water, and the other was not. All the rats received a daily injection of oestradiol-17 beta and progesterone (EP) from day 28 to day 49 of age. After EP treatment, the concentrations of AsA in the mammary glands of rats not given AsA were less than one tenth of those of rats given AsA and the contents of hydroxyproline in the mammary glands of the former rats were about half of those in the latter. Furthermore, the concentration of serum prolactin in rats not given AsA was reduced to about one third of that in rats given AsA. After EP treatment, whole mounts of mammary glands showed that in rats not given AsA the development of ducts was impaired and there was extensive accumulation of endbuds. Consistent with this finding, EP injections did not increase the area of parenchyma in the mammary glands of rats not given AsA, whereas they increased it about 2-fold in rats given AsA. Moreover, after EP treatment the amount of alpha-lactalbumin was significantly less in the mammary parenchyma of rats not given AsA than in that of rats given AsA. On the other hand, AsA deficiency did not impair the response of the mammary cells to insulin or prolactin in terms of DNA synthesis and alpha-lactalbumin production. These findings indicate that AsA deficiency impaired the development of mammary glands. This effect may be partly attributable to a defect in collagen synthesis in the mammary glands and a decrease in the concentration of serum prolactin.

Animals↗

PubMed1990

[Effects of DEAE-dextran, centrifugation, cycloheximide and their combination on infection and growth of Chlamydia psittaci bird isolates].

In order to establish a stable and uniform cultural method in a cell line HaLa 229, we studied the effect of DEAE-dextran, centrifugation, cycloheximide and their combination on infectivity and progeny yields of Chlamydia psittaci isolated mainly from birds. Of 11 strains (10 avian and one human origin Ito strain), 9 showed maximal inclusion formation when host cells were treated with a combination of dextran and cycloheximide. Of the other two strains, one showed maximum inclusion formation with dextran alone and any treatments did not enhance the inclusion formation in another strain. Maximal yields of progeny at 48 hours after infection was observed in 5 (4 avian and Ito) strains when host cells were treated with a combination of dextran and cycloheximide. One avian strain showed maximal yields with a triple treatment; dextran and cycloheximide combined with centrifugation. At 72 hours after infection, three avian and Ito strains showed maximal yields with a double treatment (dextran and cycloheximide) and other two avian strains showed that with a triple treatment (double treatment added with centrifugation). The results suggest that in a cell culture HeLa 229, the treatment with dextran and cycloheximide may provide an efficient isolation and growth pattern for most strains originated from birds.

Animals↗

PubMed1990

Immunohistochemical examination of Peyer's patches in senescence-accelerated mice.

The distribution of T cells, B cells and murine senile amyloid protein in Peyer's Patches was examined in senescence accelerated (SAM-P/1) and control (SAM-R/1) mice ranging in age from two to ten months. An immunohistochemical detection of lymphocyte surface antigens of T cells and B cells. A murine senile amyloid protein in Peyer's patches was detected by immunohistochemical staining with the specific antiserum. Congo red staining and electron microscopy. The T cell population increased and B cell population decreased slightly with age in SAM-P/1 mice, but little change was observed with age in SAM-R/1 mice. Murine senile amyloid protein positive spots were seen surrounding the vessels of the thymus-dependent area at 6 months of age, and were observed throughout the Peyer's patches at 10 months of age, but were not observed by 10 months of age in SAM-R/1 mice.

Aging↗

PubMed1990

[Hemodynamic changes with sufentanil-oxygen anesthesia for open heart surgery--a comparison of patients with beta-blocking medication or without it].

We investigated hemodynamic changes in patients undergoing coronary artery bypass grafting (CABG) and valve replacement. The former had been medicated with beta-blocking agent until the morning of operative day. On the other hand, the latter received no medication. We measured systolic arterial pressure (SAP), diastolic arterial pressure (DAP), mean arterial pressure (MAP), heart rate, and rate pressure product (RPP) at the following five points; before induction of anesthesia, immediately before intubation, immediately after intubation, one minute after skin incision and one minute after sternotomy. In both groups, SAP and DAP decreased significantly after induction; heart rate did not change during our study; and RPP decreased significantly after skin incision. There were no significant differences between the group with beta-blocking agent and the group without it. These results suggest that beta-blocking agents exert no influence in our study, and sufentanil-oxygen anesthesia produce hemodynamic stability for open heart surgery.

Adrenergic beta-Antagonists↗

PubMed1990

[Comparison of sufentanil and fentanyl anesthesia for coronary artery bypass grafting--changes in stress hormones].

We compared the changes in hemodynamics and stress hormones in 30 patients who received for CABG operation either sufentanil-oxygen or fentanyl-oxygen anesthesia. The mean doses of fentanyl and sufentanil for intubation were 1.66 +/- 0.69 mg and 0.35 +/- 0.14 mg respectively and mean total doses were 6.91 +/- 1.14 mg and 1.68 +/- 0.38 mg, or 21.4 micrograms.kg-1.hr-1 and 4.5 micrograms.kg-1.hr-1 respectively. SAP decreased significantly immediately before intubation in both groups. Immediately after intubation, a significant intergroup difference (P less than 0.05) was noted. The changes in DAP and MAP were almost similar to those of SAP. This study demonstrates that sufentanil-oxygen anesthesia gave more stable hemodynamic parameters before and after intubation. Especially no significant changes in heart rate occurred immediately after intubation and with CABG operation, thus preventing the increase in rate pressure product during procedure. Sufentanil anesthesia did attenuate more effectively the stress hormones release than high dose fentanyl anesthesia, but neither sufentanil nor fentanyl anesthesia could prevent the increases in these hormones postoperatively.

Aged↗

PubMed1989

Delay of astrocyte reaction in the injured cerebral cortex of hypothyroid mouse.

Reactive change in the number of astrocytes in the stabbed cerebral cortex (layers II-VI) of the hypothyroid mouse was studied quantitatively over a 4-day period after stabbing, by immunohistochemistry for glial fibrillary acidic protein (GFAP) and S-100 protein. The reactive increase in the number of GFAP-positive astrocytes was delayed in the hypothyroid mouse, compared to that in the euthyroid mouse. The number of S-100-positive astrocytes neither increased nor decreased significantly in the hypothyroid and the euthyroid mice. [3H]Thymidine autoradiography showed that the time course and intensity of the reactive proliferation of astrocytes were the same in the hypothyroid mouse as in the euthyroid mouse. These results indicate that hypothyroidism delays the reactive expression of GFAP-antigen and delays the transformation of GFAP-negative astrocytes into GFAP-positive reactive astrocytes.

Animals↗

PubMed1989

Reactions of S-100-positive glia after injury of mouse cerebral cortex.

Reactions of glial cells after stab wounding of mouse cerebral cortex were studied by [3H]thymidine autoradiography combined with immunohistochemistry for S-100 protein. S-100-positive cells in the stabbed cortex had the light and electron microscopic characteristics of astrocytes, and they showed remarkable hypertrophic changes 4 to 5 days after stabbing. There were many cells labeled with [3H]thymidine in the stabbed cortex from 24 h to 8 days after stabbing, and the number of labeled cells was maximum at 48 h. A few of the labeled cells were S-100-positive, and the labeled S-100-positive cells were seen 24 h to 6 days after stabbing, mostly after 72-96 h. By successive injections of [3H]thymidine for 6 days after stabbing, about 90% of labeled cells were S-100-negative, and about 90% of S-100-positive cells were unlabeled with [3H]thymidine. The increase in number of S-100-positive cells by day 6 after stabbing was not statistically significant (P greater than 0.05). These results suggest that reactive proliferation of astrocytes is a minor phenomenon in gliosis of injured cerebral cortex, in contrast with their remarkable reactive hypertrophy.

Animals↗

PubMed1989

Immunological characterization and clinical implication of cobalamin binding protein in human gastric cancer.

Cobalamin (vitamin B12) binding protein was purified from gastric cancer extracts and from serum-free culture medium of cancer cell line KATOH-III. The molecular weight, determined by immunoprecipitation and sodium dodecyl sulfate-polyacrylamide gel electrophoresis, was 70,000 and the pI was 2.8 to 3.2. From biochemical and immunological properties, this cobalamin binding protein was considered to be an isoprotein of cobalamin R binder. Monoclonal antibodies were produced against saliva R and cobalamin binding protein in culture medium to study their antigenic determinants. Monoclonal antibody 55-D reacted to an epitope of peptide in both binders, whereas WK-1 and H-12 reacted to determinants of a carbohydrate moiety, including sialic acid, in cancer cell-derived binder. In addition, we carried out an enzyme-linked immunoassay and examined plasma levels of immunoreactive R binder in patients with gastric cancer (n = 72), benign gastrointestinal disease (n = 30), and healthy individuals (n = 40). Even in patients without liver metastasis, the level of immunoreactive R binder detected by monoclonal antibody H-12 was elevated in some patients and decreased after excision of the tumor. R binder was also elevated in cancer tissue extract. Immunoreactive binder was histochemically detected in the cytosol of cancer cells and metaplastic cells of the gastric mucosa. The present findings suggest that cobalamin R binder is de novo synthesized in gastric cancer cells and that its plasma level increases in some patients. This binding protein may be a useful diagnostic and therapeutic parameter.

Adult↗

PubMed1989

Detection of glycoproteins as tumor-associated Hanganutziu-Deicher antigen in human gastric cancer cell line, NUGC4.

NUGC4 cells derived from a human gastric cancer gave 6% Hanganutziu-Deicher (HD) antigen-positive cells by flow cytometric analysis using an affinity-purified chicken antibody to N-glycolyneuraminyl-lactosyl-ceramide (HD3 ganglioside). The cells showed no HD antigenic ganglioside by thin-layer chromatography enzyme-immunostaining; however, they were revealed to contain HD antigenic proteins with molecular masses of 150, 100, 90, 70, 65, 60, 47, and 40 kDa, by both immunoblotting after sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoprecipitation of [35S]-methionine-labeled proteins, followed by SDS-PAGE and autoradiography. Neuraminidase treatment destroyed the antigenicity of all proteins, indicating that these molecules are glycoproteins and have N-glycolyneuraminic acid at the non-reducing terminal of carbohydrate chains as an HD antigenic epitope.

Antigens, Heterophile↗

PubMed1989

Polypeptide chain fold of human transforming growth factor alpha analogous to those of mouse and human epidermal growth factors as studied by two-dimensional 1H NMR.

The 1H NMR spectrum of human transforming growth factor alpha (TGF-alpha) was analyzed almost completely by the sequential assignment method using two-dimensional NMR techniques. On the basis of the nearly complete sequence-specific resonance assignment, secondary and tertiary structures of human TGF-alpha in solution (pH 4.9, 28 degrees C) were determined to satisfy the upper limits of proton-proton distances derived from nuclear Overhauser effect experiments. Although human TGF-alpha and mouse epidermal growth factor (EGF) share 27% homology in amino acid sequence, the backbone chain folds in the two growth factors are quite similar. The structure and function of TGF-alpha is well characterized by the "mitten model" previously proposed for mouse EGF. The gross shape of the TGF-alpha molecule resembles a mitten. TGF-alpha interacts with the receptor as a mitten would grasp an object. However, there is an appreciable structural difference between the two growth factors in the back of the mitten that is formed by the N-terminal polypeptide segment. This is consistent with the evidence that the backs of these molecules are not involved in the receptor binding.

Amino Acid Sequence↗

PubMed1989

Inhibitory effect of progesterone on cell death of mouse uterine epithelium.

The protective effect of progesterone against cell death of mouse uterine epithelium was evaluated by examining the retention of 5'-[125I]iodo-2'-deoxyuridine [( 125I]IdUrd) incorporated into the whole uterus and the apoptotic index (percentage of apoptotic cells in total cells), which is a good index of physiological cell death. Castrated adult female mice were given a daily injection of oestradiol-17 beta for 3 days, and then an injection of [125I]IdUrd. They were then divided into 4 groups, which received a daily injection of vehicle only, oestradiol-17 beta (E), progesterone (P), or both oestradiol-17 beta and progesterone (EP), and were killed at intervals during these treatments for determination of 125I radioactivity retained in the whole uterus. On treatment with vehicle only, the 125I radioactivity retained in the uterus decreased rapidly, but treatment with E, P or EP reduced the loss of 125I radioactivity significantly. Progesterone did not antagonize the effect of oestradiol-17 beta on the 125I radioactivity retained in the uterus. The apoptotic index of uterine cells was examined by a similar experimental protocol, but without injection of [125I]IdUrd. In the group treated with vehicle only, the apoptotic indices of both luminal and glandular epithelia increased markedly, but the injection of E, P or EP suppressed these increases significantly. Progesterone did not antagonize the effect of oestradiol-17 beta on the apoptotic index. The apoptotic index of stroma was not affected by the injection of E, P or EP. On the other hand, progesterone completely inhibited the increase in the mitotic index of uterine epithelia induced by oestradiol-17 beta. These results show that progesterone alone or in combination with oestrogen reduced cell death in mouse uterine epithelium and that the effects of oestrogen and progesterone on uterine cell death were independent of their actions on cell division.

Animals↗

PubMed1989

pH dependence of the reaction rate of His 48 with p-bromophenacyl bromide and of the binding constant to Ca2+ of the monomeric forms of intact and alpha-NH2 modified phospholipases A2 from Trimeresurus flavoviridis.

The phospholipase A2 of Trimeresurus flavoviridis was found to show monomer-dimer equilibria. Under conditions where the enzyme exists predominantly in the monomeric form, the chemical reaction rate of p-bromophenacyl bromide (BPB) with the catalytic group, His 48, was studied at 25 degrees C and ionic strength 0.2 by measuring the residual enzymic activity using a fluorescent substrate, 1,2-bis[4-(1-pyreno)butanoyl]-sn-glycero-3-phosphorylcholine (diPBPC). The pH-dependence curve of the reaction rate for the intact enzyme was practically the same as that for the modified enzyme, in which the N-terminal alpha-NH2 group had been selectively converted into an alpha-keto group. The pH-dependence curves were monophasic (sigmoidal) with a midpoint at pH 7.53, which corresponds to the pKa value of His 48. The pH dependences of the binding constants of Ca2+ to the intact and the alpha-NH2 modified enzymes were also studied at 25 degrees C and ionic strength 0.2 by measuring the changes in the tryptophyl fluorescence and/or aromatic CD spectra. The pH-dependence data for the modified enzyme were interpreted in terms of participation of Asp 49 (pKa 5.40) and His 48 (pKa 7.53), assuming that the protonation of Asp 49 competes with the Ca2+ binding. The pH-dependence data for the intact enzyme were similarly interpreted in terms of participation of the alpha-NH2 group (pKa 9.40) in addition to that of Asp 49 (pKa 5.40) and His 48 (pKa 7.53).(ABSTRACT TRUNCATED AT 250 WORDS)

Acetophenones↗

PubMed1989

Interactions of monodispersed and micellar substrates with a phospholipase A2 from Trimeresurus flavoviridis.

Bindings of the phospholipase A2 from Trimeresurus flavoviridis to the monodispersed and micellar n-alkylphosphorylcholines (n-CnPC) were studied at 25 degrees C and ionic strength 0.2 by the aromatic CD and tryptophyl fluorescence methods, respectively. The bindings to micelles of the substrate analog were analyzed by assuming that the micellar surface has multiple binding sites for the enzyme and that these sites are identical and mutually independent. The enzyme binding site was found to accommodate a constant number of the substrate (monomer) molecules, N = 9-13. The binding constant to the micelle was about 40 times greater than it was to the monodispersed substrate. The binding constant to the micellar substrate analog increased on the binding of Ca2+ to the enzyme and decreased on modification of the N-terminal alpha-NH2 group, whereas the binding to the monodispersed substrate analog was independent of pH, of the Ca2+ binding, and of the chemical modification of the alpha-NH2 group. The kinetics of the hydrolyses of monodispersed and micellar dihexanoylphosphatidylcholines (diC6PC) were studied at 25 degrees C and ionic strength 0.2 by the pH-stat method in the presence of saturating amounts of Ca2+. The catalytic center activity, kappa cat, as well as the binding constant, 1/Km, for the micellar substrate, were found to be much greater than those for the monodispersed substrate. The binding constant, 1/Km, of the monodispersed substrate was independent of pH; this was in good agreement with that of the substrate analog described above. The pH-dependence curve of kappa cat for the monodispersed substrate exhibited two transitions, one below pH 6.5 and the other above pH 9.5.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1989

B-cell function in Kawasaki disease and the effect of high-dose gamma-globulin therapy.

We studied in vitro B-cell function in Kawasaki disease (KD). By plaque-forming assay, IgG-, IgA- and IgM-secreting cells in the first week of KD were markedly increased, and recovered to a normal level in the second week in many cases. Lymphocyte blast formation with Staphylococcus aureus Cowan I (SAC), a B-cell-specific mitogen, was suppressed in the acute phase, and recovered to a normal level in the convalescent phase. By flow cytometry, HLA-DR- and HLA-DQ-positive cells were increased in the acute phase of KD. CD3- and CD4-positive cells were also decreased. CD8-positive cells showed no significant change. In five patients, CD4-positive cells with HLA-DR positivity neither increased in the acute phase nor changed during the course of illness. From our results, it can be considered that pathogenic microorganisms or toxins activate B cells directly in KD without the association of T cells. We also studied the effect of high-dose gamma-globulin therapy on B-cell function in KD. However, the results indicated that this form of therapy had no significant effect on B-cell functions.

B-Lymphocytes↗

PubMed1989

[The clinical effectiveness of OFLX in the treatment of chlamydial pneumonia].

We treated three patients of chlamydial pneumonia with OFLX, two patients were diagnosed as psittacosis and one as pneumonia associated with TWAR strain by serologic test. Three hundred mg of OFLX was orally administered three times per day and the duration of treatment was from seven to fourteen days, and we compared the clinical effectiveness of OFLX in three cases (mild: 1, moderate: 2) with that of MINO in eleven cases (mild: 3, moderate: 8), who were administered two hundred mg of MINO two times per day orally or intravenously. We isolated C. psittaci from three pet birds including case 2 and the in vitro activity of OFLX and MINO against three strains of C. psittaci was determined. Clinical effectiveness were observed and obtained results were as follows. 1) In OFLX group, three patients judged as "Good", and in MINO, one patient as "Excellent", ten as "Good". 2) The duration of pneumonic shadow was 9.33 +/- 3.21 in OFLX group, 10.3 +/- 3.50 in MINO group, and there was no significant difference between both groups. 3) The in vitro activity of OFLX and MINO against 3 strains was 0.78-1.56 micrograms/ml and 0.025 microgram/ml, respectively. From these results, it was concluded that OFLX was considered to be a useful antichlamydial agent in the treatment of mild or moderate cases of chlamydial pneumonia.

Adolescent↗

PubMed1989

Cytoprotective effect of plasmin inhibitor on necrotizing agent-induced gastric lesions in rats.

We studied the effect of plasmin inhibitor on ethanol and ammonia-induced gastric mucosal lesions in rats using an ex vivo chamber. Tranexamic acid and aminocaproic acid significantly inhibited macroscopic gastric hemorrhagic necrosis and attenuated the decrease of gastric transmucosal potential difference induced by 50% ethanol and 1% ammonia. The protection of gastric mucosa afforded by tranexamic acid and aminocaproic acid was not affected by pretreatment with indomethacin (5 mg/kg). These results suggest that plasmin inhibitor plays an important role in the prevention of gastric deep necrosis following exposure of the stomach to a damaging agent.

Aminocaproic Acid↗

PubMed1989

Effects of ammonia on the gastric mucosal barrier in rats and dogs.

We examined the effect of ammonia on the gastric mucosal barrier by measuring the changes in transmucosal fluxes of H+, Na+ and K+. In rats, ammonia at concentrations of 0.1 to 0.5% increased the H+ loss from the lumen and 0.2 to 0.5% concentrations of ammonia increased both Na+ and K+ influxes into the lumen. In dogs, in an exactly similar manner to rats, ammonia at concentrations of 0.1 to 0.5% increased H+ loss, and ammonia at concentration of 0.5% increased both Na+ and K+ influxes into the lumen. These results suggest that ammonia breaks the gastric mucosal barrier.

Ammonia↗

PubMed1989

Protective effect of taurine against ammonia-induced gastric mucosal lesions in rats.

We examined the role of gastric ammonia in the development of gastric lesions in rats. Exposure of the gastric mucosa to ammonia (30 mM) produced microscopic injury, but no macroscopic lesion was observed. However, exposure of the stomach to ammonia in rats subjected to ischemia resulted in macroscopic gastric lesions. The macroscopic lesions were markedly inhibited by pretreatment with taurine, a scavenger of hypochlorous acid (HOCI) and monochloramine (NH2Cl). These results indicate that ammonia is deleterious to gastric mucosa, and monochloramine may be involved in the pathogenesis of ammonia-induced mucosal lesions.

Ammonia↗