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Biomedical subjects

T Shibuya

Publications and source records attributed to T Shibuya.

At least 235 records · Page 13Linked to original sources
PubMed1991

Immunological analysis of acquired factor VIII inhibitor in a case with immunologic disorder.

Coagulation factor VIII inhibitor arising in a patient with autoimmune disease was immunologically analyzed. A 63-year-old man who had been diagnosed as suffering from polyarteritis nodosa was treated with prednisolone for 10 years. Severe bleeding tendency developed and coagulation studies demonstrated a high titer of inhibitor to factor VIII:C. As a result of immunological analysis, the inhibitor was found to be IgG type autoantibody having both kappa and lambda light chains. The subclasses were IgG1 and IgG4. The inhibitor recognized the COOH-terminal light chain (72-kDa thrombin fragment) on the factor VIII molecule as an epitope.

Autoantibodies↗
PubMed1991

Interleukin 4 suppresses the spontaneous growth of chronic myelomonocytic leukemia cells.

We studied the effects of IL-4 on the spontaneous proliferation of chronic myelomonocytic leukemia (CMMoL) cells in vitro. IL-4 (100 U/ml) suppressed the spontaneous DNA synthesis by approximately 50% in 5 of 8 cases examined. IL-4 (100 U/ml) also inhibited the spontaneous colony formation by CMMoL cells in a methylcellulose culture by 50-97% in all of the 10 cases in which spontaneous colonies were formed. This IL-4-mediated suppression of the growth of CMMoL cells was completely abolished by the addition of anti-IL-4 neutralizing antibodies. The spontaneous CMMoL colonies were substantially suppressed by the addition of either anti-IL-6 or anti-granulocyte/macrophage colony-stimulating factor (GM-CSF) antibodies to the colony assay system: the addition of both anti-IL-6 and anti-GM-CSF antibodies resulted in greater than 80% inhibition of the colony formation by CMMoL cells. On the other hand, none of anti-IL-1-beta, anti-granulocyte-CSF, anti-macrophage-CSF, or anti-tumor necrosis factor-alpha antibodies affected the CMMoL colony formation. In the supernatants from 24-h cultures of CMMoL cells, high levels of IL-6 and GM-CSF were demonstrated in 9 of 9 and 2 of 9 cases examined, respectively. IL-4 (100 U/ml) almost completely inhibited the secretion of IL-6 and GM-CSF by CMMoL cells. These observations suggest that IL-4 suppresses the spontaneous proliferation of CMMoL cells by inhibiting their production of IL-6 and/or GM-CSF, both of which could act in vitro as an autocrine growth factor for CMMoL cells.

Adult↗
PubMed1991

The effects of trapidil on left ventricular function and platelet aggregation in patients with coronary artery disease subjected to pacing.

The effects of the intravenous administration of 100 mg of trapidil on systolic and diastolic left ventricular functions and coronary sinus blood flow, as well as on myocardial lactate metabolism and platelet aggregation, were investigated before and after pacing in 12 patients with coronary artery disease. Pacing without administration of trapidil provoked angina in 6 of these patients. During rest, trapidil decreased the mean blood pressure by an average of 5 mmHg (from 112 +/- 15 to 107 +/- 8 mmHg, p less than 0.05) and the left ventricular end-diastolic pressure by an average of 4 mmHg (from 10 +/- 3 to 6 +/- 2 mmHg, p less than 0.05). Trapidil also caused both the max dp/dt and the coronary sinus blood flow to increase slightly, although it had no significant effect on diastolic function, myocardial lactate metabolism, or platelet aggregation. During the pacing that followed trapidil administration, chest pain was not provoked in the same 6 patients who had previously experienced chest pain on pacing. The extent of ST-segment depression also improved from -1.6 +/- 0.3 to -0.9 +/- 0.7 mm (p less than 0.05) and there was a significant suppression of the production of myocardial lactate. When pacing was terminated, trapidil caused a decrease in left ventricular systolic pressure from 173 to 156 mmHg (p less than 0.05), and also caused a decrease of the left ventricular end-diastolic pressure, from 16 +/- 4 to 8 +/- 2 mmHg (p less than 0.05). Trapidil had no significant effect on platelet aggregation activity with either a 1 microM or a 2 microM dose of ADP (adenosine diphosphate). However, the beta-TG level was suppressed, decreasing from 119 +/- 14 to 99 +/- 19 ng/ml in the arterial blood (p less than 0.1) and from 114 +/- 9 to 103 +/- 17 ng/ml (p less than 0.1) in the coronary sinus blood. Reductions in the preload and afterload by trapidil were of far greater magnitude than either its coronary dilatory or positive chronotropic effects in patients with coronary artery disease. Thus trapidil, a new antianginal agent appears to inhibit the production of platelet derived growth factors and may, therefore, protect the arteries from atherosclerosis as it promotes beneficial systemic hemodynamics in patients with depressed ventricular function.

Aged↗
PubMed1991

Effects of G-CSF, GM-CSF, and IL-5 on nuclear segmentation of neutrophils and eosinophils in congenital or acquired Pelger-Huët anomaly.

We studied the in vitro effects of granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage colony-stimulating factor (GM-CSF), and interleukin 5 (IL-5) on nuclear segmentation of neutrophils and eosinophils from three patients with congenital or acquired Pelger-Huët anomaly. After a 24-h incubation with G-CSF, the majority of neutrophils showed nuclear development characterized by a bilobed appearance. In contrast to neutrophils, the nuclear segmentation of eosinophils was not induced after incubation with G-CSF, GM-CSF, or IL-5. These results suggest that G-CSF plays some role in the nuclear development of neutrophils, whereas IL-5 may not have such an effect on eosinophil maturation in the individual cases studied.

Adult↗
PubMed1991

Schistosoma mansoni: the role of calcium in the stimulation of cercarial proteinase release.

We investigated the role of calcium mobilization in the induction of proteinase release from cercarial preacetabular glands. Proteinase release was measured by the ability of cercariae to break down a 3H-labeled proline extracellular fibroblast matrix and calcium influx was measured using 45Ca2+. The role of calcium in the activation of cercarial proteinase was examined by investigating the effects of calcium addition and removal on linoleate-induced matrix degradation, the ability of various calcium modulators (Verapamil, fendiline, nifedipine, SK-525A, BAY K-8644, Ryanodine, and SK-7171A) to stimulate or inhibit linoleate-induced proteinase release, the ability of calcium modulators directly to induce cercarial proteinase release, and the ability of various stimulants of proteinase release to induce calcium influx or efflux from cercariae. The results of these studies indicate that proteinase release is dependent on external calcium concentration, voltage-operated channels are either nonexistent in cercariae or have a minimal role in overall calcium influx, and that activation of Ca2+ influx can be caused by both free fatty acids and calcium modulators by a hypothesized receptor-operated channel. Although calcium uptake is important in cercarial proteinase release, it is not the only factor involved. Calcium uptake alone does not guarantee that proteinase will be secreted. On the other hand, if Ca2+ influx does not occur, proteinase will not be secreted.

3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethy↗
PubMed1991

A simplified method for cryopreservation of peripheral blood stem cells at -80 degrees C without rate-controlled freezing.

A simplified method was established for cryopreservation of peripheral blood stem cells (PBSCs) using hydroxyethyl starch (HES) and dimethylsulfoxide (DMSO) as a cryoprotective agent at -80 degrees C without rate-controlled freezing. The data indicate that a cryoprotective solution consisting of 6% HES and 5% DMSO produced the highest recovery rates for nucleated cells (92.0 +/- 3.5%), CFU-GM (73.8 +/- 4.1%) and BFU-E (82.2 +/- 6.9%), and the highest trypan blue viability (88.4 +/- 3.6%). For long-term cryopreservation of PBSCs, CFU-GM recovery rates remained almost unchanged during 5-18 months; the mean CFU-GM recovery rate after 18 months of cryopreservation was 70 +/- 11%. When large-scale samples of PBSCs in 100-ml freezing bags were cryopreserved for clinical use, cell and CFU-GM recoveries were similar. Using this method, 10 patients with hematological malignancy received PBSC transplants after marrow-ablative chemotherapy. All demonstrated early engraftment; seven are now alive in unmaintained complete remission for 3.5-15 months after PBSC transplant. This simple and inexpensive method will be useful for the wider application of PBSC transplant as a therapeutic alternative in the treatment of malignant diseases.

Acute Disease↗
PubMed1991

[Effects of diltiazem on hemodynamics, plasma catecholamine and renin activity during exercise in hypertension].

The effects of diltiazem on hemodynamics, plasma catecholamine and plasma renin activity were studied during treadmill exercise test in 9 cases with moderate essential hypertension. Diltiazem of 120 mg/day was orally administered for 4 weeks. At maximum exercise, significant decrease in systolic blood pressure (-32 mmHg), heart rate (-16/min), pressure-rate product (-7,883 mmHg/min), plasma norepinephrine (-195 ng/L) and plasma epinephrine (-11 ng/L) were observed; while, diastolic blood pressure, ST depression and plasma renin activity showed no significant change. Also, a significant correlation between systolic blood pressure and plasma norepinephrine (r = 0.57, p < 0.001), especially after diltiazem therapy (r = 0.68, p < 0.001), was observed. These findings indicated that diltiazem can reduce the secretion of catecholamine from the sympathetic nerves during exercise in patients with essential hypertension.

Adult↗
PubMed1991

[Treatment of iron overload with combination of recombinant human erythropoietin and phlebotomy].

A patient of Coombs negative autoimmune hemolytic anemia was massively transfused of 162 units concentrated red blood cells in 3 months and developed iron overload disease which was confirmed by liver biopsy. Hemolysis was successfully treated with high-dose methyl-prednisolone therapy and splenectomy. To treat iron overload, we administered recombinant human erythropoietin (Epo) in combination with phlebotomy. Total iron removed for 5 months was about 4 g. Thus, combination of Epo and phlebotomy was effective for the treatment of iron overload disease. Furthermore, we compared a degree of clinical effect of subcutaneous administration of Epo with that of intravenous administration in the clinical course and found the former more effective.

Adult↗
PubMed1990

Detection and identification modes for the highly sensitive and simultaneous determination of various biogenic amines by coulometric high-performance liquid chromatography.

Detection and identification modes for the rapid, selective, highly sensitive and simultaneous determination of catecholamines, indoleamines and related metabolites by high-performance liquid chromatography (HPLC) with series of coulometric working electrodes (CWE) were investigated. Five detection modes were examined: (1) oxidative single mode using a single CWE, (2) oxidative screen mode using a series of two CWE, (3) redox mode using a series of two CWE, (4) redox-reductive screen mode using a series of three CWE and (5) redox-reductive screen mode using a series of four CWE. For the highly sensitive detection of catechol compounds, oxidative single, redox and redox-reductive screen modes were suitable. Oxidative single and oxidative screen modes were better than the other modes for indole and o-methylated catechol compounds. For the selective detection of these compounds, however, the redox-reductive screen mode was best. The specific ratio obtained in HPLC with the redox or redox-reductive screen mode is useful as an index for identification purposes. These findings suggest that HPLC with the redox-reductive screen mode of detection is applicable to neuroscience studies.

3,4-Dihydroxyphenylacetic Acid↗
PubMed1990

Ca2(+)-dependent adaptive properties in the solitary olfactory receptor cell of the newt.

The time-dependent decay of the olfactory receptor potential was analyzed with a solitary cell preparation by using the whole-cell patch clamp technique. During prolonged stimulation by 10 mM N-amylacetate under standard conditions, 17 out of 63 isolated olfactory cells responded with slow depolarization. Of these 17 cells, response amplitudes in 14 cells ('phasic/tonic' response) gradually decayed within 9 s, with a half-decay time of 1.71 +/- 1.10 s (mean +/- S.D.). The relative amplitude (ratio of tonic component to peak amplitude, Vtonic/Vmax) was 0.29 +/- 0.10. The response decay was attributed to the inactivation of the odorant-activated conductance. The recovery after inactivation, which was determined with double pulse experiments, was dependent on the resting interval. The inactivation of the odorant-activated conductance was found to be observed only when the external medium contained Ca2+. In addition, it was found that the odorant-activated conductance was capable of permeating Ca2+ (PCa/PNa = 6.5), and a rise in the internal EGTA concentration (to 50 mM) inhibited the inactivation. These observations suggest that the decay of the olfactory response to prolonged stimulation is mediated by Ca2+ influx.

Animals↗
PubMed1990

Central nervous system involvement in adult T-cell leukemia/lymphoma.

Central nervous system (CNS) involvement was reviewed in 99 patients with adult T-cell leukemia/lymphoma (ATLL). Fifteen episodes of CNS involvement developed in ten of 99 patients (10.1%); nine had leptomeningeal involvement, whereas two developed intracerebral invasion, one developed cord involvement, and one developed both. CNS involvement was more frequent in the lymphoma type than in the other types of ATLL. Nuchal rigidity was not common (33%) and a syndrome of inappropriate secretion of antidiuretic hormone (ADH) occurred in association with CNS involvement (40%). Three episodes of marked hypoglycorrhachia also were noticed. The systemic progression of ATLL was the most common setting of CNS involvement (80%) and the major cause of death (80%). As for the acute and lymphoma types of ATLL, no significant difference was observed in survival between patients with and those without CNS involvement. These results indicate that CNS involvement is not an essential prognostic factor of ATLL and that it should be treated with systemic chemotherapy coupled with intrathecal chemotherapy. The control of systemic ATLL is important for the prophylaxis of CNS involvement.

Adult↗
PubMed1990

Purification of a granulocyte colony-stimulating factor from the conditioned medium of a subclone of human bladder carcinoma cell line 5637, HTB9.

A colony-stimulating factor (CSF) has been purified to homogeneity from the conditioned medium (CM) of a subclone, designated HTB9, of human bladder carcinoma cell line 5637. HTB9 cells were successfully cultured on micro-carrier beads at low-serum concentration, and the resulting CM (HTB9-CM) was concentrated by ultrafiltration. Purification procedures consisted of anion-exchange column chromatography, gel-filtration column chromatography, and reverse-phase column chromatography. The finally purified protein possessed a specific activity more than 10(8) U/mg protein for day-7 CFU-GM colony formation and exhibited a single band representing a molecular weight of 17,000 upon sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Biological activity was apparently specific for a neutrophilic granulocyte lineage of human non-phagocytic bone-marrow cells in vitro, and antiserum raised against this purified protein completely inhibited the activity of recombinant granulocyte colony-stimulating factor.

Chromatography, Gel↗
PubMed1990

Methylcholanthrene-induced murine fibrosarcoma cell line BMT-11 secretes granulocyte colony-stimulating factor.

Murine fibrosarcoma cell line BMT-11 was induced with 3-methylcholanthrene and maintained in culture. Transplantation of BMT-11 into syngeneic C57BL/6 mice produced leukocytosis consisting of marked increments of neutrophils and monocytes associated with massive splenomegaly. In order to elucidate the mechanisms of this leukemoid reaction, we studied the changes occurring in hematopoietic progenitor cells in BMT-11-transplanted mice. The numbers of granulocyte-macrophage colony-forming units (CFU-GM), erythroid colony-forming units (CFU-E), erythroid burst-forming units (BFU-E), and mixed colony-forming units (CFU-Mix) in the spleen showed dramatic 216-fold, 18-fold, 64-fold, and 80-fold increases, respectively, relative to the value in the control mice 5 weeks after the BMT-11 implantation. In contrast, the levels of progenitor cells in the bone marrow remained within normal limits. The nature of the colony-stimulating factor (CSF) secreted from BMT-11 tumor cells was also studied. BMT-11-conditioned medium (BMT-11-CM), BMT-11 tumor extract, and sera from the mice bearing transplanted BMT-11 tumor contained CSF that stimulated mainly granulocyte and macrophage lineages. Furthermore, the expression of the granulocyte colony-stimulating factor (G-CSF) gene in BMT-11 cells were detected by Northern blot analysis.

Animals↗
PubMed1990

Spontaneous remission from acute exacerbation of chronic adult T-cell leukemia.

Spontaneous remission without any anti-cancer therapy in a 57-year-old woman with adult T-cell leukemia (ATL) is reported. The patient was referred to our department because of persistent cough and appearance of abnormal lymphocytes in the peripheral blood, and she was diagnosed as having chronic ATL. Eight months later, she was re-admitted because of cystitis, watery diarrhea and worsening of respiratory symptoms with an increase of ATL cells (WBC 31 x 10(9)/l with 56% ATL cells). Acute exacerbation of ATL was diagnosed. Interestingly, antibiotic therapy for the pulmonary and urinary tract infections brought about spontaneous reduction of the ATL cell count. Spontaneous remission of ATL continued for one year without chemotherapy. The role of infection as a trigger of acute exacerbation and spontaneous remission of ATL is discussed.

Amphotericin B↗
PubMed1990

Effects of D-baclofen and L-baclofen on the trigeminal nucleus.

D-Baclofen reduced the response to L-baclofen in the feline trigeminal nucleus, the spinal cord of the rat and in patients with trigeminal neuralgia, but not in slices of hippocampus or neocortex. The iontophoretic application of 10-20 nA L-baclofen depressed excitatory transmission in the trigeminal nucleus oralis, similar to the effect of 0.1-0.4 mg/kg L-baclofen, given intravenously. The concomitant iontophoresis of 10-20 nA D-baclofen reduced the effect of iontophoretically applied L-baclofen. However, larger doses of D-baclofen (30-60 nA) did not, while still larger doses (200-400 nA) by themselves depressed response of the neuron, similar to the action of small doses of L-baclofen. The iontophoresis of 30-40 nA L-baclofen had a stronger effect than that previously obtained with systemic administration and D-baclofen was not able to block it. These observations suggest that D-baclofen is a partial agonist at the GABAB receptor. Failure to observe a blocking effect of D-baclofen in slices of hippocampus or neocortex could be due to the larger doses used or to a difference in receptor types. The observations emphasise the need to test drugs at therapeutic concentrations in an appropriate model, in order to predict reliably their therapeutic actions.

Animals↗
PubMed1990

Clinical characteristics of hybrid leukemia: report of five cases.

We studied clinical and biological features of five cases of hybrid leukemia. Three of the five patients were classified as biphenotypic leukemia because of the coexpression of myeloid/B lymphoid markers in patients 1 (FAB M2) and 2 (FAB CMMoL) and myeloid/T lymphoid markers in patient 3 (FAB M4). Patient 4 was identified as bilineal-biphenotypic leukemia because acute myelogenous leukemia (AML) (FAB M4) and acute lymphoblastic leukemia (ALL) (FAB L1) coexisted and each population coexpressed myeloid and T lymphoid markers. Patient 5 was identified as bilineal leukemia due to the conversion from AML (FAB M1) to ALL (FAB L1) at an interval of 3 months. The Philadelphia (Ph1) chromosome was negative in all cases. A leukemic blast colony formation using cell line 5637 conditioned medium as a stimulator was obtained in all four patients examined. Three of the five patients had been suffering from so-called stem cell disorders such as aplastic anemia in patient 2, trilineage myelodysplasia in patient 4 and refractory anemia with excess of blasts in transformation in patient 5. The pre-existing impairment of pluripotent stem cell was probably the background of these hybrid leukemia. Hybrid leukemia appears to have an inferior prognosis: an AML-directed chemotherapy resulted in a low remission rate (2/5) with a short duration of relapse free survival (1/2) and an ALL-directed chemotherapy produced no remission (0/3). Chronological phenotypic analysis revealed that hybrid features of leukemic blasts disappeared at the time of relapse in patient 1 and progression to AML in patient 2. Monitoring of lineage-associated markers should be required for the management of hybrid leukemia.

Adult↗