Search PubMed⌕ Search

Biomedical subjects

T Ohkubo

Publications and source records attributed to T Ohkubo.

At least 343 records · Page 19Linked to original sources
PubMed1986

Structure-taste correlation of L-aspartyl dipeptides using SIMCA method.

One of the pattern recognition techniques, the SIMCA method, has been applied to structure-taste studies on L-aspartyl dipeptides (L-Asp-NH-R). The sweet and bitter taste class models of the peptides were obtained by using five structural descriptors, such as molar refractivity, and four kinds of STERIMOL parameters. The classification rates were calculated to be 87% and 81% for sweet and bitter peptides, respectively. The SIMCA method has also suggested that two factors, shape and size, of the C-terminal amino acid moiety R in the dipeptides are extremely important to model their taste qualities.

Aspartic Acid↗
PubMed1986

Establishment of two Ph1 chromosome-positive cell lines, KPB-M8 and KPB-M15.

Two new Philadelphia (Ph1) chromosome-positive cell lines, designated KPB-M8 and KPB-M15, were established from the peripheral blood of two patients with chronic myelogenous leukemia in blastic crisis. Both cell lines were characterized by blastic appearance, the presence of acid phosphatase activity, Fc gamma-receptor, and C3-receptor, and reactivity to monoclonal antibodies such as OKM1, MCS2, MY906, MY4 and MY7. These results indicate that KPB-M8 and KPB-M15 cells are of an undifferentiated blast nature. Both cells retained Ph1 chromosome, and showed numerical and structural changes upon chromosomal analysis. These cell lines should provide a useful source for studying differentiation of hemopoietic cells.

Adult↗
PubMed1986

[Studies of inflammatory pain response: related pain producing substance and endogenous opioid system].

A method for assessing inflammatory pain response was developed by modification of the formalin test. Formalin (0.5%, 25 microliters) was injected into the hindpaw of the mouse, and the durations spent in licking or biting response were measured as an indicator of pain response. The response curve was biphasic, having two peaks, from 0 to 5 min (first phase) and from 15 to 20 min (second phase). Morphine, ethylketocyclazocine, ketocyclazocine and pentazocine inhibited the response dose-dependently at the first and the second phases. Aspirin, oxyphenbutazone and dexamethasone inhibited only the second phase. Aminopyrine and mefenamic acid which acted at both central and peripheral sites inhibited both phases; however, the inhibition of the second phase was stronger than that of the first phase. Substance P (SP) antagonist inhibited only the first phase. Bradykinin (BK) inhibitor caused a inhibition of both first and second phases, and pretreatment of compound 48/80 and indomethacin inhibited only the second phase. From these facts, it was suggested that SP and BK played a role in the pain response at the first phase, and histamine, BK and PG were involved at the second phase. Naloxone produced hyperalgesia and bestatin produced analgesia at the second phase; then, it seems that the endogenous opioid system is activated by formalin stimulation and modulates the pain perception. Based on these findings, it is presumed that the pain of the first phase is evoked by the direct stimulation of the nerve fibers, and that of the second phase is due to the inflammatory reaction.

Analgesics↗
PubMed1986

[Peripheral analgesic actions of opioid peptides and morphine analogues].

Opiates and opioid peptides were administered in the order of 10(-9)-10(-6) mol peripherally, and their action on pain sensitivity was investigated by the modified formalin test which has two characteristic pain responses (the first and the second phase) in the mouse hindpaw. Opioid peptides (20-500 pmol) had dose-dependent analgesia against both first and second phases, and their action ranked dynorphin greater than [D-Ala2, Met5]-enkephalinamide greater than [Met5]-enkephalin. EKC and morphine (0.4-2.5 nmol) inhibited pain response of the first phase, but produced hyperalgesia in the second phase dose-dependently. Lidocaine hydrochloride had peripheral analgesic action, but was about 500-10000 times weaker than these substances. So, these peripheral analgesic actions have a different mechanism from that of local anesthetic action. N-methyl levallorphan which is thought to be a peripherally selective narcotic antagonist reversed these peripheral analgesic actions at the first and second phases and also prevented the hyperalgesic effects of EKC and morphine at the second phase. Naloxone reversed analgesia at only the first phase. These results suggest that an analgesic mechanism by opioids may exist at the peripheral site as well. Furthermore, it is estimated that a receptor exists which is antagonized by N-methyl levallorphan but not by naloxone and that there is a system of hyperalgesia by EKC and morphine in pain modulation.

Analgesics, Opioid↗
PubMed1986

Interaction of bradykinin with substance P on vascular permeability and pain response.

Combination of bradykinin with substance P exerted synergistic effects on vascular permeability and pain response in mouse paw. Denervation of sciatic nerve reduced significantly bradykinin-induced vascular permeability, suggesting the involvement of sensory nerves. The bradykinin-induced vascular permeability was also reduced by intravenous injection of a substance P-antagonist. The results suggest that neuronal substance P takes part in the action of bradykinin on inflammation and pain sensation.

Animals↗
PubMed1986

Serum and urinary oestrone sulphate in pregnancy and delivery measured by a direct radioimmunoassay.

Serum and urinary levels of oestrone sulphate in pregnancy and delivery were measured by a direct radioimmunoassay without hydrolysis. The serum and urinary oestrone sulphate increased as pregnancy progressed. The mean level of serum oestrone sulphate increased to the highest peak of 494 pmol/ml at the 35th gestational week and then decreased. The mean level of urinary oestrone sulphate increased to the highest peak of 1.28 mumol/l at the 34th gestational week and then decreased. At vaginal deliveries, the mean level of maternal peripheral serum oestrone sulphate increased hourly at as high a level as 979 pmol/ml. The mean serum level of oestrone sulphate was 204 pmol/ml in the umbilical artery and 145 pmol/ml in the umbilical vein. At Caesarean section, on the other hand, the maternal peripheral serum level of oestrone sulphate averaged 362 pmol/ml. The mean serum levels of oestrone sulphate were 90.7 pmol/ml and 171 pmol/ml in the umbilical artery and umbilical vein, respectively. These results suggest a maternal origin of oestrone sulphate in pregnancy, with fluctuations in the levels being of interest in relation to labour pain.

Cesarean Section↗
PubMed1986

[Three-dimensional analysis of colonic adenoma and of carcinoma in adenoma with scanning electron microscope and sequential serial sectioning].

Three-dimensional structures were analyzed on 32 human colonic adenomas, 5 hyperplastic polyps, 4 normal colonic mucosa and 5 advanced colonic carcinomas with Scanning Electron Microscope (SEM) and with sequential serial sectioning. After SEM observation, the samples were softened with 2% NaHCO3 and observed with histological serial sectioning. By combining both techniques, that is combined analysis of outer structures for SEM and inner structures for serial sectioning, three dimensional analysis of the colonic adenoma and carcinoma in adenoma were successfully completed. The colonic adenomas were classified into 6 types based on the surface structure observed by SEM as Type I (circular type), Type II (long-elliptical type), Type III (branched type), Type IV (gyral type), Type V (wrinkle type) and Type VI (complicated type). Classified Types I, II, III and IV were observed in tubular adenoma, and grades of atypia seemed to be increased as increasing type numbers. Type V, in tubulo-villous adenoma and villous adenoma, were found out and showed severer atypia than observed in Type IV. Among 32 adenomas, 3 portions of focal cancers were detected, and the surface structures of them had highly complicated patterns as shown with Type VI.

Adenoma↗
PubMed1985

Naloxone prevents the analgesic action of alpha-MSH in mice.

alpha-MSH (0.1, 1, 10 micrograms) was administered intracerebroventricularly and its action on pain sensitivity was investigated by the hot-plate method in mice. alpha-MSH produced dose-dependent analgesia and this analgesic effect was prevented by naloxone (1 mg/kg, s.c.). It is possible that alpha-MSH may play a role in the mechanism of pain through endogeneous opioid systems.

Analgesics↗
PubMed1985

A novel Ph1 chromosome positive cell line established from a patient with chronic myelogenous leukemia in blastic crisis.

A novel Philadelphia (Ph1) chromosome positive cell line, designated KYO-1, was established from the peripheral blood of a patient with chronic myelogenous leukemia (CML) in blastic crisis. Although this line had a unique capacity to differentiate spontaneously along the erythroid and monocytoid lineages as evidenced by cytochemical analysis for the first several months, the capacity was gradually lost after repeated passages. The results suggest that KYO-1 is an undifferentiated myeloid cell line. This cell line provides a useful source for studying differentiation and proliferation of pluripotent stem cells from CML in blastic crisis.

Adult↗
PubMed1985

Objective monitoring of graft-versus-host disease: alpha 1-antichymotrypsin concentration changes after bone marrow transplantation in patients developing graft-versus-host reactions.

The levels of alpha 1-antichymotrypsin (ACT) was monitored in patients who underwent bone marrow transplantation. Seven received HLA-identical sibling bone marrow grafts, two received transplants from twins and one was given HLA-nonidentical marrow from his father. A dramatic increase of ACT was observed in all patients who developed graft-versus-host disease (GvHD). ACT did not rise at all in the case of patients who received marrow from twins, even in a patient who was given three transplants from the same donor. The patient transplanted from his father died from GvHD and the increase of ACT was the greatest fluctuation measured.

Bone Marrow Transplantation↗