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Biomedical subjects

M Nishikawa

Publications and source records attributed to M Nishikawa.

At least 613 records · Page 34Linked to original sources
PubMed1989

A new immunomodulator, FR-901235.

FR-901235 is a new type of immunoactive substance produced by an imperfect fungus, Paecilomyces carneus F-4882. The mitogen-induced lymphocyte proliferation which had been suppressed by addition of immunosuppressive factor, was restored to a normal level by the addition of FR-901235. Furthermore, the subsequent administration of FR-901235 partially restored the impaired delayed-type hypersensitivity to sheep red blood cells in tumor-bearing mice.

Adjuvants, Immunologic↗
PubMed1989

[Morphological study of experimental corneal neovascularization after anterior uveal ischemia].

We morphologically investigated what kinds of inflammatory cells infiltrate the corneoscleral limbus by light and electron microscopy and what manner of keratocytes and vascular endothelial cells appear at the corneal limbus, when the corneal edema was aggravated severely and clinical corneal new vessels were found initially, i.e. until three days after anterior segmental ischemia in rabbit eyes. The majority of infiltrating inflammatory cells were polymorphonuclear leukocytes and the others were lymphocytes and histiocytes etc. Peripheral keratocytes around limbal vessels were stimulated and transformed to fibroblastic cells as a result of anterior segment ischemia. Proliferating endothelial cells of comparatively minor limbal vessels invaded between corneal lamellar layers toward the corneal center. Polymorphonuclear leukocytes were often found near activated keratocytes proliferating vascular endothelial cells, hear and there. Consequently, it is considered that the stimulated polymorphonuclear leukocytes play an important role when corneal neovascularization occurs after anterior segmental ischemia.

Animals↗
PubMed1989

The signal transduction systems and intracellular Ca2+ dynamics in arachidonate-induced platelet activation.

Types II and III protein kinase C were expressed in human platelets and showed slightly different modes of activation and kinetic properties. Type III isozyme was more sensitive than type II for the activation of each isozyme with arachidonate (AA) although both isozymes were activated by diacylglycerol and phosphatidylserine in a similar manner. When human platelets were stimulated by AA, two types of platelet activation, a low level of AA (0.1-2.5 micrograms/ml)- and a high level of AA (10-50 micrograms/ml)-induced activations, were observed. These activations were associated with the phosphorylation of 40K and 20K proteins. Although a low level of AA (0.45-10.0 micrograms/ml) induced the formation of [32P] phosphatidate in intact platelets prelabeled with [32P] Pi, AA at high concentrations (20-50 micrograms/ml) did not stimulate phospholipase C. The incubation of fura 2 loaded platelets with a low level of AA evoked a rapid and transient elevation in [Ca2+] i. In contrast, a high level of AA induced an irreversible increase in [Ca2+] i but this [Ca2+] i elevation alone was not associated with platelet activation. These results suggest that the signal transduction system by a high level of AA on human platelets is different from that seen with a low level of AA. A high level of AA induces platelet activation, without phospholipase C stimulation, and therefore, the ability of AA to directly activate protein kinase C (pre-dominantly type III isozyme) may contribute toward the activation of platelets by a high level of AA.

Arachidonic Acid↗
PubMed1989

[Cerebral hemodynamics and functional prognosis in hydrocephalus].

The functional outcome of cerebral hemodynamics in the chronic stage of juvenile hydrocephalus was determined using single photon emission computed tomography (SPECT). Five patients including three with aqueductal stenosis, one with post-meningitic hydrocephalus, and one case with hydrocephalus having developed after repair of a huge occipital encephalocele. Early images of cerebral blood flow (CBF) were obtained 25 minutes after intravenous injection of 123-I-Iodoamphetamine (IMP), and late images were scanned 3 hours later. Cerebral blood volume (CBV) was also measured using 99mTc in three patients. Twenty cases with adult communicating hydrocephalus were also investigated from the point of view of shunt effectiveness. Although there was no remarkable change in the cerebrovascular bed in the juvenile cases, CBF of the remnant brain parenchyma was good irrespective of the degree of ventricular dilatation. There was a periventricular-reduced IMP uptake in each case, however it somehow matched the ventricular span. Functional outcome one to 23 years after the initial shunt operation was good in every case, despite multiple shunt revisions. Redistribution on late images had no bearing on clinical states. In adult cases, 8 patients with effective shunting demonstrated a relatively localized periventricular low perfusion, with preoperative increased cerebrospinal fluid (CSF) pressure. On the contrary, 12 patients with no improvement with or without shunting showed disproportionately widespread periventricular-reduced IMP uptake, despite low CSF pressure. The present study indicates that periventricular hemodynamics may play an important role in cerebral function compromised by hydrocephalus.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

The effects of ciclosporin on the renal histopathological aspects in (NZB x NZW)F1 mice.

Ciclosporin A (CYA) is a newly developed immunosuppressant and has a sparing effect on suppressor cell regulatory mechanism. However, accumulation of experimental animal studies has not been enough for the administration of CYA to human autoimmune diseases such as lupus nephritis. In this study, the histopathological aspects of the kidney in (NZB x NZW)F1 mice after administration of CYA were analysed. A dose of 25 mg/kg/day of CYA was injected intraperitoneally so that serum level of CYA was controlled from 250 to 300 ng/ml with this dosage. Typical histopathological changes of lupus nephritis including wire-loop lesions were observed in the kidney of the non-treated control group. In contrast, only few lesions were demonstrated in the CYA-treated group. These results suggest that CYA prevented the renal deterioration in lupus mice.

Analysis of Variance↗
PubMed1989

Intensive chemotherapy followed by autologous bone marrow transplantation for a patient having wide-spread embryonal carcinoma in the central nervous system.

A patient with an intracranial embryonal carcinoma, which was resistant to cisplatin-based combined chemotherapy and radiotherapy, developed spinal seeding. Alpha fetoprotein (AFP), human chorionic gonadotropin (HCG) and the beta chain of HCG (NCG beta) in serum or cerebrospinal fluid immediately returned to elevated levels despite sequential chemotherapy and resection. Accordingly, we treated this patient with spinal irradiation and intensive combination chemotherapy (cisplatin etoposide, vinblastine, cyclophosphamide and actinomycin D) followed by autologous bone marrow transplantation. With this treatment, the clinical manifestations showed a tendency to improve and, furthermore, the serum levels of AFP and HCG returned to normal. These findings suggest autologous bone marrow transplantation to be a potential approach to the treatment of patients with embryonal carcinomas.

Adult↗
PubMed1989

[Spontaneous transient remission in adult acute myeloid leukemia].

A spontaneous complete remission for one month duration was observed in a 54-year-old female with acute myeloid leukemia. She had no documentation of apparent infection and blood transfusions, although they were ordinarily associated with spontaneous remission.

Female↗
PubMed1989

Putative involvement of protein kinase C in proliferation of human myeloid progenitor cells.

The effects of two different potent inhibitors of protein kinase C, 1-(5-isoquinolinylsulfonyl)-2-methylpiperazine (H-7) and staurosporine on human myeloid (CFU-C) and late erythroid progenitor cells (CFU-E) were studied using an in vitro clonal assay. Our objective was to determine whether protein kinase C has a role in signal transduction related to proliferation of these committed progenitor cells. The presence of H-7 or staurosporine led to an inhibition of colony formation stimulated by crude colony-stimulating factor (CSF), interleukin-3 (IL-3), granulocyte-macrophage CSF (GM-CSF), granulocyte CSF (G-CSF), or macrophage CSF (M-CSF) in a dose-dependent manner. N-(2-guanidinoethyl)-5-isoquinolinesulfonamide (HA-1004), a weaker analog of H-7, did not inhibit proliferation of CFU-C. Neither H-7 nor staurosporine had any effect on CFU-E formation. H-7 and staurosporine dose-dependently inhibited the protein kinase C from K562 cells. The potential of these compounds to inhibit proliferation of CFU-C correlated well with the magnitude of their inhibition of protein kinase C from K562 cells. The inhibition of proliferation of CFU-C appears to relate to the potential of these compounds to inhibit protein kinase C. Thus, activation of protein kinase C is presumably involved in the proliferation of CFU-C, and the regulatory system of CFU-E appears to differ from that of CFU-C.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗
PubMed1989

[Factors responsible for prognosis of chronic subdural hematomas].

239 adult patients with chronic subdural hematoma were reviewed in order to analyse recent characteristics, and the responsible factors affecting functional prognosis. Patients with hygroma, diagnosed by the nature of the subdural fluid, were included since the mode of treatment is regarded as the same. 226 cases were surgically treated with standardized two burr-holes and irrigation, within which 24 cases required reoperation and 13 cases were medically treated since the hematoma was small and there was no mass effect. Functional outcome was evaluated by the Glasgow Outcome Scale. The number of cases have gradually increased, especially among elderly patients and in female ones. 179 patients were categorised as having good recovery, 25 as moderately disabled, 27 as severely disabled, 3 as persistently vegetative, and 5 patients died. Aged patients with preoperative mental change and a disturbance of consciousness, with low dense or mixed dense hematoma without sizable mass effect, with watery-clear or xanthochromic fluid cavity tended to have poorer outcome. Also the prognosis of patients not operated on was poor despite the spontaneous disappearance of the cavity. The delay in re-expansion of the brain had less bearing on the functional prognosis than might be expected. The factors which impeded good recovery were primary brain damage due to preceding diseases such as cerebral infarct or hemorrhage, initial head injury, parkinsonism, and postoperative psychiatric disturbances. The mean age of these patients was significantly higher than those with good recovery.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

[Morphological study of corneal edema after anterior segment ischemia].

This experiment was performed to investigate the correlation between morphological changes of the corneal endothelium and clinical corneal edematous opacities after a procedure causing obstruction of bilateral long posterior ciliary arteries of the albino-rabbits. Shortly after the procedure, corneal endothelium became irregular on the anterior-chamber side and there were numerous lysosomal granules in the cytoplasm of corneal endothelial cells. On the third day, endothelial cells became necrotic and collapsed and a part of the cells peeled into the anterior chamber. Fibroblast-like cells and inflammatory cells were piled up in severely damaged areas of the endothelium. On the 11th day, the corneal endothelium developed again as a single layered structure on Descemet's membrane. It's seemed that corneal edema was induced as a result of severe damage corneal endothelium exposed to biochemical mediators such as prostaglandins released into the aqueous humor because the severity of corneal edema indicated some relation to changes in the concentration of prostaglandins in aqueous humor after anterior segmental ischemia.

Animals↗
PubMed1988

Possible involvement of direct stimulation of protein kinase C by unsaturated fatty acids in platelet activation.

Arachidonate and other unsaturated fatty acids stimulated platelet protein kinase C in a dose-dependent manner (5-50 micrograms/ml), when the activity was assayed with either isolated substrates or the platelet cytosol. When human platelets were stimulated by arachidonate, two types of platelet activation were observed. Platelet activation induced by a low level of arachidonate (0.1-5 micrograms/ml) was inhibited by aspirin, but activation induced by a high level of arachidonate (10-50 micrograms/ml) was not. These activations were associated with the phosphorylation of 40K and 20K proteins. Other unsaturated fatty acids (10-50 micrograms/ml) also induced platelet aggregation which was not inhibited by aspirin. Arachidic acid and methyl arachidonate, which did not stimulate protein kinase C, also did not induce platelet responses. Although a low level of arachidonate (0.45 microgram/ml) induced the rapid and transient formation of [3H]-1,2-diacylglycerol and [32P]phosphatidate in intact platelets with [3H]arachidonate or [32P]Pi, unsaturated fatty acids at a high concentration (50 micrograms/ml) did not stimulate phospholipase C. Incubation of fura 2 loaded platelets with a high level of unsaturated fatty acids evoked a rise in cytosolic Ca2+-concentration ([Ca2+]i) but this [Ca2+]i elevation alone was not associated with platelet activation. These results suggest that a high level of unsaturated fatty acids induces platelet activation, without phospholipase C stimulation, and that the ability of unsaturated fatty acid to directly activate protein kinase C may contribute toward the activation of platelets by a high level of unsaturated fatty acid.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗
PubMed1988

Regulation of embryonic smooth muscle myosin by protein kinase C.

Phosphorylation of the 20-kDa light chain regulates adult smooth muscle myosin; phosphorylation by the Ca2+/calmodulin-dependent enzyme myosin light chain kinase stimulates the actomyosin ATPase activity of adult smooth muscle myosin; the simultaneous phosphorylation of a separate site on the 20-kDa light chain by the Ca2+/phospholipid-dependent enzyme protein kinase C attenuates the myosin light chain kinase-induced increase in the actomyosin ATPase activity of adult myosin. Fetal smooth muscle myosin, purified from 12-day-old fertilized chicken eggs, is structurally different from adult smooth muscle myosin. Nevertheless, phosphorylation of a single site on the 20-kDa light chain of fetal myosin by myosin light chain kinase results in stimulation of the actomyosin ATPase activity of this myosin. Protein kinase C, in contrast, phosphorylates three sites on the fetal myosin 20-kDa light chain including a serine or threonine residue on the same peptide phosphorylated by myosin light chain kinase. Interestingly, phosphorylation by protein kinase C stimulates the actomyosin ATPase activity of fetal myosin. Moreover, unlike adult myosin, there is no attenuation of the actomyosin ATPase activity when fetal myosin is simultaneously phosphorylated by myosin light chain kinase and protein kinase C. These data demonstrate, for the first time, the in vitro activation of a smooth muscle myosin by another enzyme besides myosin light chain kinase and raise the possibility of alternate pathways for regulating smooth muscle myosin in vivo.

Adenosine Triphosphatases↗
PubMed1988

[Clinical studies on assay for Na-K ATPase in human blood cells. I. Erythrocyte Na-K ATPase assay in patients with thyroid dysfunction and in those with chronic renal failure].

A number of erythrocyte Na-K ATPase units were measured in 22 patients with hyperthyroid Graves' disease, 3 with primary hypothyroidism, 3 with simple obesity, 13 with chronic renal failure on hemodialysis, and 20 normal controls, using ouabain binding assay as described by DeLuise et al. The number of Na-K ATPase units, derived by maximal binding of 3H-ouabain, was decreased in patients with simple obesity (Mean +/- SD, 0.26 +/- 0.07 pmol/10(9) RBC), as compared with that in normal controls (0.39 +/- 0.10), and a significant negative correlation between the number of the binding sites and the ratio of the measured body weight to the optimal body weight calculated by the modified Broca's method was observed in normal controls and patients with obesity (r = -0.51, p less than 0.05). The results agreed closely with that reported by DeLuise et al and provided validation of our estimates of the erythrocyte Na-K pump units. The maximal 3H-ouabain binding was significantly diminished in patients with hyperthyroid Graves' disease (0.28 +/- 0.07) when compared with that in normal controls, while the bindings were significantly elevated in patients with hypothyroidism (0.91 +/- 0.26). These results were in disagreement with those previously reported by animal studies where Na-K ATPase was found to be stimulated by thyroid hormones. It might be possible to partly explain this discrepancy by the degradation of Na-K ATPase in erythrocytes in addition to the apparent differences between erythrocytes and the other tissues and by the length of time that the tissue was exposed to the action of the hormones. Therefore, erythrocyte from normal controls and patients with hyperthyroid Graves' disease were divided into low and high density portions by a discontinuous 'percoll' density gradient centrifugation, and the bindings of the erythrocytes in two portions were separately measured. The bindings of erythrocyte in the higher density portion, representing relatively old-aged erythrocyte, were diminished to 92 +/- 19% of the bindings of the original whole erythrocytes in normal controls. An even more marked reduction of the maximal bindings of 3H-ouabain in old-aged erythrocytes was observed in patients with hyperthyroid Graves' disease (72 +/- 26%). Moreover, this % reduction based on aging related significantly to serum T4 concentrations in those patients (r = 0.85, p less than 0.05). These findings suggest that the number of erythrocyte Na-K ATPase units may reflect the overall peripheral metabolic state, regulated by thyroid hormone-dependent thermogenesis.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1988

[Clinical studies on abnormal thyroid stimulators in patients with Graves' disease. I. A sensitive assay for thyroid-stimulating antibodies using cultured porcine thyroid cells and polyethylene glycol precipitation of serum].

The activities of thyroid-stimulating antibody (TSAb) in serum from patients with Graves' disease were measured by a sensitive assay, using cultured porcine thyroid cells and the precipitation from serum with polyethylene glycol (PEG), and the activities were compared with those of thyrotropin binding inhibitor immunoglobulin (TBII), measured by the commercial assay kit. Porcine thyroid cells after digestion were cultured for 15-18 hours with TSH of 1-10,000 microU/ml or the precipitations of sera from normal subjects and patients with Graves' disease or Hashimoto's thyroiditis, and then the cAMP levels in the culture medium were determined by the commercial RIA assay kit (Yamasa). The precipitation was obtained by adding 0.5 ml of 30% PEG solution to 0.5 ml serum, and was resuspended with 0.6 ml of Hanks' medium without NaCl, containing 1.5% bovine serum albumin, 20mM Hepes and 0.5 mM 3-isobutyl-1-methylxanthine. The precipitation contained about 85% of immunoglobulin and 63% of albumin of the original amount of the serum, as well as substantial TSH, when the original serum contained TSH more than 40 microU/ml. When the PEG precipitations from 10 normal subjects were incubated with the thyroid cells of 4 X 10(5) cells, the cAMP releases into the medium ranged from 83 to 124%, when the mean value was calculated as 100%. Therefore, the cAMP release of more than 130% of the amount released into the culture medium incubated with normal IgG was judged as positive TSAb activity. The minimum detectable quantities were regarded as about 5 microU/ml TSH equivalent. TSAb and TBII activities were detected in 48 (92%) and 50 (96%) of 52 patients with untreated hyperthyroid Graves' disease, respectively, and either TSAb or TBII activities were detected in 16 (80%) of 20 patients with Graves' disease maintained in a clinically euthyroid state by treatment with antithyroid drugs. TBII was positive in 10(50%) of these patients. Some patients showed distinct discrepancies in these two activities, although there was a significant positive correlation between TSAb and TBII activities (r = 0.53, p less than 0.01) in patients with untreated Graves' disease. In these patients, TSAb activities showed a significant positive correlation with values for 99mTc thyroid uptake, determined 30 min after the injection. However, they did not show any significant correlation with serum T4 or T3 concentrations. Similarly, TBII showed significant correlations with goiter size and 99mTc thyroid uptake. To conclude, the present assay for TSAb is sensitive and reproducible.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1988

[Clinical studies on abnormal thyroid stimulators in patients with Graves' disease. II. Clinical significance of measuring TSAb and TBII in patients with euthyroid Graves' disease and patients with hyperthyroid Graves' disease during antithyroid drug treatment].

To evaluate the clinical significance of TBII and TSAb activities in euthyroid and hyperthyroid Graves' disease, these two activities were measured in 8 patients with euthyroid Graves' disease and 29 patients with hyperthyroid Graves' disease during treatment with antithyroid drugs. In 8 patients with euthyroid Graves' disease, TBII activity was detectable only in one patient and TSAb activity detected in 3 patients, these detectabilities being much lower than those in hyperthyroid Graves' disease. However, 2 of 4 patients who had either TSAb or TBII came to have both activities, and one of them became overt hyperthyroid. In patients with hyperthyroid Graves' disease, detectabilities of these activities became lower as they became euthyroid with antithyroid drug treatment, but TSAb tended to be higher than TBII when they remained euthyroid for more than 4 months. Although the majority of the patients who had TSAb and/or TBII activities were T3 non-suppressible, patients with no TSAb and TBII activities did not necessarily show remission of the disease. The present results suggest that patients with euthyroid Graves' disease with both TBII and TSAb may be apt to become hyperthyroid, and that TSAb and TBII activities and T3 suppressibility may not be a definite criteria for the remission of Graves' disease.

Adolescent↗
PubMed1988

[Studies on the pituitary and thyroid function in patients with nonthyroid illnesses].

Serum thyroid hormone and TSH concentrations were determined in patients with nonthyroidal illnesses (NTI) including 26 patients with chronic renal failure on hemodialysis, 15 patients with end-stage malignancy and 21 normal controls. Serum TSH levels were measured by a highly sensitive immunoradiometric assay Kit (RIA-gnost hTSH) and free-T4 levels were determined not only by both back-titration method and T4 derivative method, but also by magnesium precipitation method using equilibrium dialysis. TSH levels in normal controls ranged from 0.6 to 2.4 microU/ml. In 40 of 41 patients with NTI, serum T3 levels were less than 100 ng/dl, and 37 patients had diminished T3 levels, as compared with those in normal controls. Moreover, serum T4 levels were also diminished in 19 patients with NTI, and T4 levels related significantly to serum TBG levels in all patients with NTI (r = +0.76, p less than 0.01), suggesting that the diminution of T4 levels in patients with NTI can be explained partly by decreased TBG levels. However, it was remarkable that free T4 levels in serum, determined by RIA kits, were decreased in approximately half of the patients with NTI. Free T4 levels by the magnesium precipitation method were still lower in these patients when compared with those in normal controls. Serum TSH levels in patients with NTI showed a wide scattering from below to above the normal range, and the mean value was not significantly different from that in normal controls. No significant relations were found between TSH levels and T4, T3, or free T4 levels in patients with NTI.(ABSTRACT TRUNCATED AT 250 WORDS)

Diabetic Nephropathies↗