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Biomedical subjects

A Miwa

Publications and source records attributed to A Miwa.

At least 127 records · Page 7Linked to original sources
PubMed1993

Effect of KRN2391, a novel vasodilator, on various experimental anginal models in rats.

The antianginal effect of KRN2391, N-cyano-N'-(2-nitroxyethyl)-3-pyridinecarboximidamide monomethanesulfonate, on various anginal models in rats was compared with those of nifedipine and nicorandil. Angina pectoris was induced by methacholine or isoproterenol, and the change in the ST-segments in the electrocardiogram (ECG) was used as the parameter to indicate angina pectoris. The intracoronary administration of methacholine (3 micrograms) produced an elevation in the ST-segment of the ECG. This ST-elevation was inhibited by the intravenous administration of KRN2391 (30 and 100 micrograms/kg), nifedipine (100 and 300 micrograms/kg) and nicorandil (1000 and 3000 micrograms/kg). The administration of isoproterenol (10 micrograms/kg/min, i.v.) produced a depression of the ST-segment of the ECG. The intravenous administration of KRN2391 (100 micrograms/kg), nifedipine (100 micrograms/kg) and nicorandil (3000 micrograms/kg) inhibited the ECG changes induced by isoproterenol. These results suggest that KRN2391 exerts a potent protective effect on angina pectoris models compared with nifedipine and nicorandil. KRN2391 appears to be useful as an antianginal drug.

Angina Pectoris↗
PubMed1993

Bleeding tendency caused by the deposit of amyloid substance in the perivascular region.

A 55-year-old woman, who had systemic amyloidosis associated with multiple myeloma, had sudden development of hematomas of her lip and upper eye lid. There was no evidence of deterioration of multiple myeloma, thrombocytopenia nor deficiency of coagulation factors. Biopsy specimen showed the deposit of amyloid substance in the dermis and perivascular region. The bleeding tendency in this patient with myeloma was likely due to the deposit of amyloid substance in the vascular wall; improvement was achieved with administration of hemostatic agents.

Adrenochrome↗
PubMed1993

[Refractory bilateral pneumothoraces complicated with interstitial pneumonitis after bone marrow transplantation].

We report here a case of 33 year-old-man with refractory bilateral pneumothoraces during the treatment for interstitial pneumonitis 6 months after bone marrow transplantation (BMT). He was diagnosed as having acute myelogenous leukemia (AML) M1. He was treated with chemotherapy, and cerebral irradiation. BMT was performed in August 1989 from a sibling donor whose human leukocyte antigen was matched, ABO blood type mismatched. Preconditioning regimen was cyclophosphamide and total body irradiation (TBI). BMT was successful without major graft versus host disease. Thereafter he complained of respiratory symptom and was admitted on June 14 1990. Computed tomogram (CT) scan showed interstitial and alveolar shadows. We started the treatment against bacterial infection, Pneumocystis carinii, cytomegalovirus (CMV) and against interstitial pneumonitis with bolus dose of steroid. The transbronchial lung biopsy specimen revealed interstitial pneumonitis without typical CMV nor pneumocystis carinii pneumonia. Although a CT scan showed improvement of pneumonitis, bilateral pneumothoraces occurred. The adhesion therapy became successful after the reduction of steroid dosage. A pneumothorax rarely occurs after BMT. In this case it is speculated that TBI might be responsible for interstitial pneumonitis, and the steroid might have inhibited the adhesion therapy of pneumothorax.

Adult↗
PubMed1993

[Severe bleeding in a case of factor VIII inhibitor associated with intravascular lymphomatosis].

A 70-year-old man was admitted to Jichi Medical School Hospital on October 1, 1990, complaining of spontaneous severe hemorrhage in his extremities. He had prolonged APTT value and normal PT value. Factor VIII level was markedly diminished, and a high titer of factor VIII inhibitor was observed. He was diagnosed as having idiopathic factor VIII inhibitor because of no sign of underlying disorders. He received prednisolone and immunosuppressants, subsequently with plasma exchange and bolous factor VIII, resulting in disappearance of the inhibitor. He was admitted again in February 1991, because of the reappearance of factor VIII inhibitor. In June, furthermore, bone marrow smears showed infiltration of atypical B cells, although no evidence of organomegaly and adenopathy was observed. Therefore, he was suspected to have primary bone marrow lymphoma. He received CHOP therapy, but he died of multiorgan failure. Postmortem autopsy demonstrated multifocal intravascular lymphomatosis with marked intravascular involvement of the lung, liver, kidney, adrenal glands, spleen and bone marrow. Lymph nodes were not swollen, showing little evidence of intravascular lymphomatosis.

Aged↗
PubMed1992

Calmodulin-binding proteins of calcium-independent type in rat brain synaptosomal membranes: their localization and properties.

Some properties of calmodulin(CaM)-binding proteins (CaMBPs) of the Ca(2+)-independent type were investigated in the synaptosomal membrane (SM) from rat brain using the [125I]CaM gel overlay method. When SM was prepared in the presence of Ca2+, Ca(2+)-independent CaM binding was decreased, whereas the Ca(2+)-dependent type was not altered. All Ca(2+)-independent-type CaMBPs were membrane-bound and scarcely present in the soluble fractions. When SM was heat-denatured, the 24/22.5-kDa CaMBPs could no longer be detected by [125]CaM binding and a new component with higher molecular mass (greater than 200 kDa) was shown to bind CaM in a Ca(2+)-independent manner. A possible effect of cAMP- and Ca2+/CaM-dependent phosphorylation on CaM binding was also examined.

Animals↗
PubMed1992

Lung carcinoma with spindle cell components: sixteen cases examined by immunohistochemistry.

Sixteen cases of lung carcinoma with spindle cell components were studied by conventional histochemistry and immunohistochemistry. The epithelial components were squamous cell carcinoma in six cases, adenocarcinoma in four, adenosquamous carcinoma in five, and large cell carcinoma in one. In every case sarcomatous areas were distinctly observed and, in general, neoplastic spindle cells proliferated in close proximity to the epithelial elements. Some of the histochemical procedures suggested mesenchymal features in the stroma of the exophytic portions of three cases, but heterogeneous elements, such as bone or striated muscle, were not observed. By immunohistochemical examination the epithelial elements showed positive reactions for keratin, epithelial membrane antigen, and/or carcinoembryonic antigen to a varying degree according to the histologic types. The spindle cell elements revealed a positive immunoreaction for keratin in all but one case. Epithelial membrane antigen was demonstrated in sarcomatous areas of only five cases and carcinoembryonic antigen was not expressed at all. In contrast, vimentin was distinctly demonstrated in sarcomatous areas of five cases, although other mesenchymal markers, such as desmin, actin, and myosin, were negative. These findings indicate that the spindle cell components in these 16 cases may represent mesenchymal features with partial or complete loss of epithelial features.

Aged↗
PubMed1992

Disturbance of membrane function preceding ischemic delayed neuronal death in the gerbil hippocampus.

Slice preparations were made from the hippocampus of gerbils after 5 min of ischemia by carotid artery occlusion and the membrane properties of pyramidal neurons were examined. A majority of CA1 neurons lost the capacity for long-term potentiation following tetanic stimulation of the input fibers. CA3 pyramidal neurons, in contrast, preserved responses similar to those in the normal gerbil. Following ischemia, CA1 pyramidal neurons showed increased spontaneous firing that was highly voltage dependent and was blocked by intracellular injection of the Ca2+ chelator, EGTA. Thirty-five percent of CA1 neurons showed an abnormal slow oscillation of the membrane potential after 24 h following ischemia. Intracellular injection of GTP gamma S or IP3 produced facilitation of the oscillations followed by irreversible depolarization. Our results indicate that ischemia-damaged CA1 neurons suffer from abnormal Ca2+ homeostasis, involving IP3-induced liberation of Ca2+ from internal stores.

Animals↗
PubMed1992

[The vasospasmolytic effects of nicorandil, cromakalim and pinacidil on 3,4-diaminopyridine-induced phasic contractions in canine coronary arteries as an experimental vasospasm model].

The spasmolytic mechanisms of nicorandil, a novel antianginal drug, were investigated using 3,4-diaminopyridine (3,4-DAP)-induced phasic contractions of isolated canine coronary arteries in comparison with those of cromakalim and pinacidil. Nicorandil (10(-4) M), cromakalim (10(-6) M) and pinacidil (10(-5) M) suppressed the phasic contractions. Pretreatment with glibenclamide (10(-6) M), a specific blocking agent of ATP-sensitive K+ channel, eliminated the suppression of phasic contractions by these drugs; glibenclamide completely eliminated the suppression by cromakalim, while the eliminations against nicorandil and pinacidil were incomplete. The recoveries of peak tensions were only 56.8% and 76.1% for nicorandil and pinacidil, respectively. Nicorandil and pinacidil may suppress the phasic contractions via K+ channel opening and additional mechanisms. Methylene blue (10(-7)-10(-5) M) alone, a guanylate cyclase inhibitor, had no effect on the suppression of phasic contractions by nicorandil. In the presence of glibenclamide (10(-6) M), however, the pretreatment with methylene blue significantly augmented the recovery of peak tension for nicorandil. These results indicate that K+ channel openers may suppress the phasic contractions induced by 3,4-DAP via ATP-sensitive K+ channels, and that additionally, nicorandil may suppress the phasic contractility through guanylate cyclase stimulation, as a nitrate.

4-Aminopyridine↗
PubMed1992

Two cases of acute myeloid leukemia evolving into a chronic myelomonocytic leukemia-like state after induction therapy.

Two patients with acute myeloid leukemia (AML) developed a chronic myelomonocytic leukemia (CMMoL)-like state after chemotherapy. Both patients showed morphological evidence of myelodysplasia together with acute leukemia at presentation (Case 1: M5b with trilineage myelodysplasia and Case 2: M4 with dysmegakaryocytopoiesis). They also showed persistent monocytosis without prominent blast cell proliferation after induction therapy. The possibility was suggested that these two patients were in acute transformation from CMMoL at presentation and returned to a CMMoL-like state after induction therapy.

Aged↗
PubMed1992

[A case of systemic lupus erythematosus complicated with monoclonal CD5 + B cell proliferation suspected as chronic lymphocytic leukemia].

A case of systemic lupus erythematosus (SLE) complicated with monoclonal CD5 + B cell proliferation in peripheral blood and bone marrow is reported. A 59-year-old man suffering from left chest pain was admitted to the hospital because of thrombocytopenia (platelets 1.9 x 10(4)/mm3). The diagnosis of SLE was made from (1) pleuritis (2) autoimmune thrombocytopenia (3) positive anti-DNA antibodies, positive LE cell preparation (4) positive antinuclear antibodies. Prednisolone 60mg per day was started. From that time monoclonal CD5 + B cells began to increase in peripheral blood (maximum lymphocyte counts 11000/mm3, CD5 + B cells 77.6%) and bone marrow, and the complication of chronic lymphocytic leukemia (CLL) was suspected. It is said that patients of CLL often have various autoantibodies, and in about 15% of CLL patients complicate autoimmune hemolytic anemia, but those who develop collagen diseases are rare. And while lymphoid malignancies occur more often in the patients of SLE in comparison with normal subjects, the reports of the patients who complicate the proliferation of monoclonal CD5 + B cells like CLL are very few. But from many facts that indicate the relation between CD5 + B cell or its proliferation and the production of autoantibodies or autoimmune diseases, we consider this case worth to be reported.

Antigens, CD↗
PubMed1992

Cloning and sequence analysis of the evgAS genes involved in signal transduction of Escherichia coli K-12.

We have cloned and sequenced new Escherichia coli genes which belong to member of the family of environmentally responsive two-component system and named evgA and evgS because their amino acid sequences were found the most homologus to the Bordetella pertussis bvgA and bvgS. They were mapped at 51 min. and extending from 6B9 to 7G9 in the Kohara miniset library of the E. coli chromosome. In fact, both EvgA and EvgS proteins predicted from their DNA sequences were identified in the in vitro coupled transcription translation system. When the evgA and evgS were expressed on multiple copy plasmid in an envZ deletion strain, ompC expression was also regulated by temperature, MgSO4 and nicotinic acid, by which virulence of Bordetella pertussis is controlled via BvgA and BvgS. These results indicate that ompC expression was controlled by in vivo cross-talk via EvgA and EvgS which can work in E. coli the same way as BvgA and BvgS.

Bacterial Outer Membrane Proteins↗
PubMed1992

[Intrapericardial lipoma with stenosis of the left bronchus and pulmonary artery].

In a 1-year-6 month-old girl with asthma, a chest magnetic resonance imaging revealed an intrapericardial lipoma at the site of the transverse sinus behind the great arteries. The tumor compressed the left bronchus and pulmonary artery resulting in the stenosis. Under cardiopulmonary bypass, the tumor was successfully removed. The stenosis of the left bronchus and pulmonary artery were released.

Bronchi↗
PubMed1992

[Burkitt's lymphoma with granulocytosis and a high level of C-reactive protein].

A case of Burkitt's lymphoma with granulocytosis including immature cells and a high level of C-reactive protein (CRP) is reported. The activity of interleukin-1 alpha (IL-1 alpha) was detected in the sera, although its activity was not detected in the supernate of the cultured lymphoblasts. The lymphoblasts stimulated production of IL-1 alpha from human umbilical endothelial cells. Therefore, the lymphoblasts infiltrating bone marrow may have stimulated production of IL-1 alpha from bone marrow stroma cells, and IL-1 alpha may have induced granulocytosis and a high level of CRP.

Aged↗
PubMed1991

Establishment and characterization of a human leukemic cell line with megakaryocytic features: dependency on granulocyte-macrophage colony-stimulating factor, interleukin 3, or erythropoietin for growth and survival.

A new human leukemia cell line with megakaryocytic features, designated UT-7, was established from the bone marrow of a patient with acute megakaryoblastic leukemia. Surface marker analysis revealed that the majority of the cells reacted with monoclonal antibodies against platelet glycoprotein Ib (CD42b), glycoprotein IIb/IIIa (CD41a), MY 7 (CD13), MY 9 (CD33), and glycophorin A antigens. Cytogenetic analysis showed a human male near-tetraploid karyotype with a modal chromosome number of 92-96. Flow cytometry-derived DNA histograms demonstrated that the majority of the cells spontaneously contained 4 N DNA ploidy levels. Ultrastructural study showed that platelet peroxidase activity was weakly positive but myeloperoxidase activity was negative. Ferritin and theta-granule, which have been used as ultrastructural markers for the erythroid lineage, could not be detected. In response to phorbol myristate acetate, platelet factor 4 and beta-thromboglobulin, which were specifically synthesized in the process of megakaryocyte maturation, dramatically increased in UT-7 cells. This was accompanied by an increase in cell size, ploidy level, platelet peroxidase activity, and the surface density of glycoprotein IIb/IIIa antigen. These findings suggest that UT-7 is a new leukemic cell line with megakaryocytic features and with the potential to differentiate into cells with more mature megakaryocytic properties in response to phorbol myristate acetate. This cell line showed strict dependency on interleukin 3 (IL-3), granulocyte-macrophage colony-stimulating factor, or erythropoietin. The maximal effective doses of IL-3, granulocyte-macrophage colony-stimulating factor, and erythropoietin for proliferation in liquid culture were 10 units/ml, 1 ng/ml, and 1 unit/ml, respectively. These concentrations were comparable to the doses that maximally stimulate the clonal growth of normal hemopoietic cells. IL-6 could stimulate the proliferation of UT-7 cells but not maintain the line in long-term culture. UT-7 cells may be a useful model for (a) the analysis of gene regulation of megakaryocytic maturation-associated proteins expressed in the process of megakaryocytic differentiation and (b) the study of signal transduction of hemopoietic factors associated with megakaryocytopoiesis.

Antigens, CD↗
PubMed1991

A voltage-clamp study of the effects of Joro spider toxin and zinc on excitatory synaptic transmission in CA1 pyramidal cells of the guinea pig hippocampal slice.

Using the single-electrode voltage-clamp technique, we have examined the effects of a non-N-methyl-D-aspartate (NMDA) antagonist. Joro spider toxin (JSTX), and of an NMDA antagonist, zinc, on excitatory postsynaptic currents (EPSCs) evoked by stimulation of stratum radiatum in CA1 pyramidal cells of the guinea-pig hippocampal slice. Pressure application of a synthesized JSTX (JSTX-3) at 10-200 microM greatly reduced the EPSCs (14/19 cells). The block by JSTX-3 was observed in pyramidal cells where the EPSCs showed linear peak current-voltage (I-V) relations in the control. EPSCs remaining after JSTX-3 application showed non-linear peak I-V relationships (10/14 cells), and were blocked by puff application of the selective NMDA receptor antagonist DL-2-amino-5-phosphonovalerate (APV) at 200 microM (6/10 cells). In the presence of JSTX-3, the decay time constant of the EPSC was increased and was less affected by membrane potential. JSTX-3 had no detectable effects on EPSCs apparently mediated solely by NMDA receptor. These observations suggest that JSTX-3 blocks excitatory synaptic transmission mainly by suppressing non-NMDA-receptor-mediated EPSCs, and that the JSTX-3-insensitive component is mediated at least in part by NMDA receptors in the hippocampal slice. Zinc (100-200 microM) reversibly attenuated EPSCs (6/9 cells) and appeared to block a slower component of the EPSCs, suggesting that mainly NMDA receptor-mediated currents were affected.

2-Amino-5-phosphonovalerate↗
PubMed1991

Differential diagnosis of pleomorphic adenoma by immunohistochemical means.

Immunohistochemical study of major salivary gland tumours was performed on 60 pleomorphic adenomas, five basal cell adenomas and 10 adenoid cystic carcinomas to determine the diagnostic value of each antigen. Immunoreactivity examined were intermediate filaments (keratin, vimentin, desmin and glial fibrillary acidic protein [GFAP]) and related substances (actin, S-100 protein and secretory component). In pleomorphic adenomas, there was positive immunoreactivity for GFAP which was not observed in normal tissue or other neoplastic tissues. Immunoreactivity of GFAP was closely related to myxomatous and early chondromatous differentiation in pleomorphic adenoma. It is considered that GFAP immunoreactivity should be assessed in the occasional differential diagnostic dilemma of pleomorphic adenoma versus adenoid cystic carcinoma and basal cell adenoma, because of its ability to show potential and definite myxochondromatous differentiation.

Adenoma↗
PubMed1991

[Pituitary and plasma levels of growth hormone (GH), follicle stimulating hormone (FSH) and luteinizing hormone (LH) in hereditary dwarf rats (rdw/rdw)].

Koto et al found a new hereditary dwarf mutation from breeding colony of Wistar-Imamichi rat and named 'rdw'. To characterize endocrinological functions in rdw rats, pituitary and plasma levels of pituitary hormones including growth hormone (GH), follicle stimulating hormone (FSH) and luteinizing hormone (LH) were compared between rdw and normal rats. The hormone levels were estimated with radioimmunoassay (RIA). It was found that pituitary and plasma levels of GH of rdw were drastically decreased and those of FSH and LH were inclined to decrease but not remarkable as compared with normal. Rats of rdw were, therefore, considered to be useful as a model animal for endocrinological defects.

Animals↗