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T Akabane

Publications and source records attributed to T Akabane.

At least 19 recordsLinked to original sources
PubMed2006

Marked species differences in the bioavailability of midazolam in cynomolgus monkeys and humans.

The bioavailability (F) of midazolam in cynomolgus monkeys (0.02) was markedly lower than that in humans (0.24-0.46) and the reason for this difference in F between the two species was investigated. Based on the area under the plasma concentration-time curve after intravenous and intraportal infusion to cynomolgus monkeys, the hepatic availability (F(h)) was estimated as 0.66. The fraction of dose absorbed (F(a)) estimated from the single-pass intestinal perfusion method was 1.0 in cynomolgus monkeys. The intestinal availability (F(g) = F/F(a)/F(h)) was calculated as 0.03 in cynomolgus monkeys. Since the F(a) of midazolam has been reported to be almost 1.0 in humans, F(h) and F(g) were calculated as 0.33-0.76 and 0.46-1.00 when the reference values for hepatic blood flow (1026-1530 ml h(-1) kg(-1)) were used. In conclusion, the main reason for low F in cynomolgus monkeys was the markedly higher first-pass intestinal metabolism seen in cynomolgus monkeys compared with humans.

Administration, Oral↗
PubMed1998

Changes of ischemic heart disease in Utsunomiya, Japan, over 10 years: a survey of primary care physicians.

A total of 502 patients presenting in Utsunomiya city and its suburbs during a 10-year period were studied to determine the clinical features of ischemic heart disease and to identify coronary risk factors. The male/female ratio was 1.21, but the ratio decreased with increasing age. The duration of chest pain showed a continuous spectrum between angina and infarction, with a short duration of chest pain not being useful for excluding the diagnosis of myocardial infarction. Hypertension was more common than hypercholesterolemia in this study, although the prevalence of the latter increased slightly with time, along with the shift towards a modernized occupational pattern. Smoking was a more important risk factor for ischemic heart disease in younger individuals than in the elderly, and diabetes mellitus was highly associated with the development of myocardial infarction. The incidence of radiologically diagnosed cardiac hypertrophy and aortic calcification decreased over time. These changes may have resulted in part from improved blood pressure control and the development of new anti-hypertensive and cholesterol-lowering agents.

Age Factors↗
PubMed1998

Effect of theophylline withdrawal on airway inflammation in asthma.

Theophylline has been used as a bronchodilator in acute and chronic asthma management, although there is accumulating evidence that it may have anti-inflammatory effects. We have investigated the effect of theophylline withdrawal for 6 weeks in asthmatic subjects whose peak expiratory flow (PEF) readings were more than 80% of the predicted value and its variability was less than 20% (Green Zone) by treatment with both a moderate dose of inhaled corticosteroids (BDP), 400-800 microg/day) and low dose theophylline (400 mg/day) for more than 3 months. In 38 asthmatic subjects, changes in clinical symptoms, respiratory function and airway inflammation detected with hypertonic saline induced sputum, and airway reactivity to histamine were investigated. One half of the patients were randomly withdrawn from theophylline, while the other half continued to take the same dose of theophylline for a period of 6 weeks. Mean steady state plasma theophylline concentrations when receiving treatment with theophylline were 8.08 microg/mL in the theophylline withdrawal group and 7.64 microg/mL in the control theophylline group, respectively. Although a significant increase in asthma symptoms emerged in the theophylline group, there were no significant changes in the theophylline administration group. In the theophylline withdrawal group, there were small but significant falls in PEF in the morning, FEV1 and V50 at the end of the study period. Analysis of induced sputum showed that there was also a significant increase in the percentage of total and activated (EG2+) eosinophils only in those patients who withdrew from theophylline. These results indicate that chronic treatment with low dose theophylline exerts an anti-inflammatory effect and that the additional use of theophylline with inhaled corticosteroids provides an effective treatment for moderate asthma. Taken together, we conclude that theophylline has long-term beneficial effects on the chronic asthma management.

Administration, Oral↗
PubMed1996

Taste-modifying triterpene glycosides from Staurogyne merguensis.

Five new oleanane-type triterpene glycosides named strogins 1-5 were isolated from leaves of Staurogyne merguensis. Their structures were determined on the basis of chemical and spectral evidence. After strogins 1, 2 and 4 were held in mouth, water elicited a sweet taste. On the other hand, strogins 3 and 5 had no activity. The structure-activity relationship is discussed.

Glycosides↗
PubMed1995

Ventricular gradient variability. New ECG method for detection of ischemic heart disease.

The usefulness of ventricular gradient variability for detecting the presence of ischemic heart disease was evaluated in 38 patients with coronary artery disease (group 1), 21 patients with chest pain and no coronary artery disease (group 2), and 33 healthy control subjects. The ventricular gradient of each consecutive heartbeat at rest over a 22-second interval was calculated using a microcomputer. The SD and coefficient of variation for azimuth, elevation, and magnitude were used as indices of ventricular gradient variability. The SD and coefficient of variation of both the magnitude and elevation of ventricular gradient in group 1 were significantly greater than those of the other two groups (P < .01, respectively). When the normal upper limit was defined as 2SD above the mean value in the control group, a comparison between the findings for group 1 and group 2 revealed that the coefficient of variation of magnitude of the ventricular gradient was the most sensitive (82%) and specific (91%) index for coronary artery disease (chi-square test, P < .001). This study suggests that the variability in the magnitude of the ventricular gradient is a reliable index of ischemic heart disease.

Electrocardiography↗
PubMed1995

Activity and stability of a new sweet protein with taste-modifying action, curculin.

Curculin elicited a sweet taste. After the sweetness of curculin diminished, application of deionized water or an acid to the tongue induced a sweet taste. The maximum sweetness of curculin itself was equivalent to the sweetness of 0.35 M sucrose. The maximum sweetness induced by 0.02 M citric acid or deionized water after curculin dissolved in a buffer of pH 6.0 was held in mouth for 3 min was also equivalent to that of 0.35 M sucrose. The sweetness induced by deionized water was completely suppressed by the presence of 1 mM CaCl2 or MgCl2, while that induced by an acid was not suppressed by the presence of divalent cations. Based on these results, the mechanism of the taste-modifying activity was discussed. Stability of curculin was examined under various conditions. The taste-modifying activity of curculin was unchanged when curculin was incubated at 50 degrees C for 1 h between pH 3 and 11.

Citrates↗
PubMed1994

Effects of microsphere suspension agents on systemic hemodynamics in rats. Comparison of nonradioactive colored and radioactive microspheres.

The systemic hemodynamic effects of different microsphere suspension agents were evaluated in 22 Sprague-Dawley male rats. Rats were divided into three groups, and three different solutions (distilled water; n = 7, 10% dextran; n = 8, and 70% glucose; n = 7) were injected through the left atrium respectively. 0.2 ml of each solution was injected repeatedly until significant hemodynamic changes developed. During four sequential injections, distilled water had no significant effects on cardiac output, mean arterial pressure, and heart rate. However, the 10% dextran (mol wt 70,000) solution produced significant decreases in both cardiac output and mean arterial blood pressure during and after the third injection. The 70% glucose solution also decreased, cardiac output significantly during the third injection. Although microspheres itself must cause some hemodynamic changes, our results indicated that the hemodynamic disturbances observed during a large dose injection of microspheres might have been at least in part due to the use of high-density suspending solutions. The doses of radioactive microsphere solution in many previous rat studies were usually less than 0.6 ml. However, in the case of large dose injection of microspheres, these results indicate that the suspending solutions can affect hemodynamic parameters in various ways.

Animals↗
PubMed1992

An enzyme immunoassay and immunoblot analysis for curculin, a new type of taste-modifying protein: cross-reactivity of curculin and miraculin to both antibodies.

We have developed an enzyme immunoassay method for curculin, a new type of taste-modifying protein. This method can accurately quantify 0.05-20 ng of curculin, a sensitivity about 3000-times that of the psychometric method. The content of curculin in the fruit of Curculigo latifolia increased gradually until 3 weeks after artificial pollination and dramatically at 4 weeks, to finally reach 1.3 mg per fruit. Immunoblot analysis indicated that antiserum to curculin was faintly reactive with miraculin, but not with thaumatin or monellin.

Cross Reactions↗
PubMed1992

[Clinical evaluation of effects of KRN8601 (rhG-CSF) on neutropenia].

Clinical effects of KRN8601 (recombinant human granulocyte colony-stimulating factor:rhG-CSF) were studied in 26 patients with chronic neutropenia including 4 Kostmann's disease, 1 Shwachman's syndrome, 1 Lonsdale's syndrome, 1 glycogen storage disease Ib-associated, 6 chronic benign, 5 chronic hypoplastic, 2 cyclic, 4 autoimmune and 2 miscellaneous neutropenia. The patients were given rhG-CSF intravenously at doses of 20-540 micrograms/m2 or subcutaneously at doses 20-400 micrograms/m2, over the periods of 2-32 weeks. Increases in neutrophil counts occurred after rhG-CSF administration in 23 of the 26 patients. Patients with Kostmann's disease, Shwachman's syndrome and chronic hypoplastic neutropenia responded poorly compared to patients with other types of neutropenia. There were no serious side effects which caused interruption of the study. These results indicated a beneficial effect of KRN8601 in various types of chronic neutropenia.

Adolescent↗
PubMed1991

[Requirements of diagnostic criteria for aplastic anemia in children].

As a general rule, diagnostic criteria of aplastic anemia in children are the same as adult criteria. However, blood counts of normal children show wide age-related variation, therefore we must establish a system of adjustment for diagnosis of aplastic anemia in children. The data of children with aplastic anemia visiting our institutes from 1966 to 1990 were evaluated for this study. RBC below 350 x 10(4)/microliters, WBC below 4,000/microliters or neutrophils below 1,500/microliters, platelets below 8 x 10(4)/microliters, reticulocytes below 4 x 10(4)/microliters and lymphocytes over 60% were seemed to satisfy the diagnostic criteria of aplastic anemia proposed by the Study Group of hemopoietic Disorders sponsored by the Ministry of Health and Welfare of Japan. Fifteen children (4.6%) did not meet these criteria and as such were diagnosed as atypical aplastic anemia. Thirteen of them were in a pre-aplastic state and developed typical aplastic anemia within 6 months to 8 years after the initial diagnosis. Clinical findings of these patients showed the decrease in number of megakaryocytes and committed stem cells in bone marrow. Three of these patients developed acute non-lymphocytic leukemia, and 2 of them were diagnosed as Fanconi's anemias.

Adolescent↗
PubMed1990

Induction of mixed erythroid-megakaryocyte colonies and bipotential blast cell colonies by recombinant human erythropoietin in serum-free culture.

The effects of recombinant human erythropoietin (rEp) on murine hematopoietic progenitors were studied using a serum-free culture. A high concentration of rEp stimulated the formation of mixed erythroid-megakaryocyte colonies (EM colonies) and blast cell colonies, as well as erythroid colonies, erythroid bursts, and megakaryocyte colonies from normal mouse bone marrow cells. Direct effects of rEp on EM colony, megakaryocyte colony, and erythroid burst formation were confirmed by depletion of accessory cells such as T cells, B cells, and macrophages from crude bone marrow cells, and inhibition of the colonies by the addition of rabbit anti-rEp antibody to the culture in a dose-dependent fashion. Replating experiments were performed to confirm the differentiating ability of blast cell colonies grown in the presence of rEp. Most of the blast cell colonies yielded not only secondary erythroid colonies but also megakaryocyte colonies in the presence of 2 IU/mL rEp. Some of the blast cell colonies produced secondary EM colonies in the presence of 16 IU/ml rEp of 2 IU/mL rEp plus interleukin-3, although no granulocyte-macrophage colonies were found in the secondary culture. These results suggest that Ep acts not only as a late-acting factor that is specific for erythroid progenitors, but also as a bipotential EM-stimulating factor for murine hematopoietic cells.

Animals↗
PubMed1990

Detection of engraftment and chimerism after bone marrow transplantation by in situ hybridization using a Y-chromosome specific probe.

After bone marrow transplantation (BMT), the recipient and donor cells must be distinguished from each other to document and characterize successful engraftment. In addition to dot blot and Southern blot analyses, we have performed in situ hybridization in two sex-mismatched cases using a Y-chromosome specific DNA probe (PHY10). In situ hybridization showed that greater than 95% of the peripheral mononuclear cells had clusters of grains indicative of male cell origin in a recipient girl (case 1), and no cells had clusters of grains in another recipient boy (case 2) at the time of engraftment and 3 months after BMT. In situ hybridization using the PHY10 probe appears to facilitate identification of individual cells of male and female origin, and it requires only 20 hr to obtain the results. The technique provides a powerful new method for the documentation of engraftment and the detection of mixed hematopoietic chimerism in peripheral blood and bone marrow cell compartments after BMT.

Blotting, Southern↗
PubMed1990

An increase in polymorphonuclear leucocyte chemotaxis accompanied by a change in the membrane fluidity with age during childhood.

Leucocyte membrane fluidity affects cell deformability as well as the accessibility of receptors and the degree of their exposure on the membrane. These effects modulate the subsequent cellular responsiveness. We have assayed membrane fluidity of polymorphonuclear leucocytes of children, using an excimer-forming lipid technique in flow cytometry, and evaluated its relation to their chemotaxis to a formyl peptide. We report that membrane fluidity and chemotaxis of polymorphonuclear leucocytes are increased with age. These findings may have important implications for the physiological processes in polymorphonuclear leucocyte motility during childhood.

Adult↗
PubMed1990

Pseudo-Chediak-Higashi anomaly in acute myeloid leukemia (M2) of childhood.

The frequency and clinical significance of the pseudo-Chediak-Higashi (PCH) anomaly were studied in 20 children with acute myeloid leukemia (AML) M2 in the FAB nomenclature. PCH granules were recognized as giant eosinophilic granules, measuring up to 5 microns, in the cytoplasm of leukemic cells on smears. At the electron microscope level, most PCH granules were round to oval and outlined by a limiting membrane, and contained homogeneous, granular, crystalloid, rod-like or myelin-like materials. The PCH anomaly was demonstrable in five (25.0%) of the 20 patients, which indicates that the anomaly is not rare in childhood AML M2. There were no differences between PCH anomaly-positive and PCH anomaly-negative groups with regard to hepatosplenomegaly, hemoglobin levels, white blood cell counts, bone marrow cellularity, t(8q-, 21q+) chromosome abnormalities or prognoses. Circulating leukemic cells were observed less frequently in the PCH anomaly-positive group than in the PCH anomaly-negative group (p less than 0.05); the leukemic cells were not demonstrable in three of the five patients in the former group, although they were detected in all 15 patients in the latter group. The existence of PCH granules and/or a defect of the cytoskeleton responsible for the PCH anomaly in leukemic cells may impede their movement from the bone marrow to the peripheral blood.

Adolescent↗
PubMed1990

Transient abnormal myelopoiesis and diffuse hepatic necrosis in Down's syndrome with prominent bleeding diathesis.

The first case known to us with Down's syndrome with transient abnormal myelopoiesis and diffuse hepatic necrosis is reported. The infant had prominent bleeding diathesis and hepatosplenomegaly. She died on the 7th day because of intractable bleeding. The autopsy disclosed extramedullary hematopoiesis and extensive hepatic cell necrosis. Characteristic in our case was the outstanding bleeding diathesis due to coagulopathy.

Bone Marrow↗
PubMed1990

[Treatment of aplastic anemia with KRN8601 (rhG-CSF)].

Thirty-nine patients with severe or moderate aplastic anemia received treatment with recombinant human granulocyte colony-stimulating factor (rhG-CSF). The first group of eight patients received rhG-CSF in doses of 100 to 400 micrograms/m2/d by a daily 30-minute intravenous infusion for one or two weeks. Doses up to 400 micrograms/m2/d were well tolerated and resulted in increases of neutrophil counts in 5 out of 8 patients. We gave rhG-CSF (400 micrograms/m2/d) to the second group of 26 patients by a daily 30-minute intravenous infusion for two weeks. The treatment resulted in an increase of neutrophil counts in 15 out of 26 patients (3.1 to 29.5 fold). Further, higher doses (800 or 1,200 micrograms/m2/d) were administered in 5 patients who did not respond to the dose of 400 micrograms/m2/d. The treatment increased the neutrophil counts in 3 out of 5 patients. The third group of five patients received rhG-CSF subcutaneously in doses of 20 to 400 micrograms/m2/d. An increase of neutrophil counts was noted in all five patients. Differential counts of bone marrow aspirate revealed an increase of myeloid: erythroid ratios. However, the responses were transient and neutrophil counts returned to basal levels within 1 approximately 2 weeks after discontinuing treatment. No severe toxicity due to rhG-CSF was observed. These results suggest that rhG-CSF is effective on stimulating granulopoiesis in patients with aplastic anemia. This treatment will be particularly useful for the patient with aplastic anemia suffering from bacterial or fungal infections.

Adolescent↗