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Biomedical subjects

M Kurosawa

Publications and source records attributed to M Kurosawa.

At least 109 records · Page 6Linked to original sources
PubMed1995

[A case of polymyositis presenting histological picture of bronchiolitis obliterans organizing pneumonia with transbronchial lung biopsy specimens].

A 69-year-old woman was admitted to our hospital because of slight fever, general fatigue, joint pain and proximal muscle weakness. Severe elevation of serum enzyme levels of CPK, transaminase and aldolase was noted. The chest roentgengram showed diffuse reticular and nodular infiltrates. Histological examination of the transbronchial lung biopsy specimens revealed alveolitis and organizing pneumonia. Daily administration of 80 mg predonisolone was effective for both lung findings and myositis.

Aged↗
PubMed1994

Chronic myeloid leukemia presenting ALL-type BCR/ABL transcript.

We investigated the breakpoints of the bcr gene in 46 Ph1-positive CML cases by Southern blot analysis of bcr rearrangement, and in 17 CML cases by a combination of Southern blot analysis and RT-PCR. By Southern blot, the breakpoint was not identified on M-bcr in three CML cases, of which one case showed the P210-type bcr/abl transcript and two cases showed the ALL-type (P190-type) bcr/abl transcript with or without P210 transcript. Later two cases showed unique hematological profiles such as thrombocytosis, mild myelofibrosis, and relative resistance to alkylating agents. Therefore, the present study suggests that expression of the P190-type transcript may affect clinical and hematological findings in CML.

Adult↗
PubMed1994

Point mutation of K-ras gene codon 12 in biliary tract tumors.

BACKGROUND/AIMS: Point mutations of the K-ras gene have been reported in a wide variety of human tumors. However, there might be conflicting data about its presence or incidence in biliary tract tumors. The aim of this study is to elucidate the presence and types of point mutation in biliary tract tumors, including gallbladder carcinoma and adenoma, extrahepatic bile duct carcinoma, and ampullary carcinoma. METHODS: Mutation bands detected in modified two-step polymerase chain reaction were eluted from agarose gel and analyzed by dideoxy sequencing method. RESULTS: Of 20 biliary tract tumors showing a mutation band, G to A single base substitutions were confirmed in 15 cases as the most frequent changes, which were divided into changes for aspartic acid (GAT) and (14) serine (AGT) (1). Changes for valine (GTT) were found in two cases. In extrahepatic bile duct carcinoma, duplicate mutations (GA/TT) were found in two cases and triplicate mutation (A/GA/TT) in one case. The adenoma portion of one "cancer in adenoma" case of gallbladder showed the single base transition (GAT) in the second position, same as in the carcinoma portion. CONCLUSIONS: Most of the biliary tract tumors comprised point mutation in K-ras gene codon 12, and G to A transition was the most frequent.

Adenoma↗
PubMed1994

In vivo antitumor activity of herbimycin A, a tyrosine kinase inhibitor, targeted against BCR/ABL oncoprotein in mice bearing BCR/ABL-transfected cells.

Herbimycin A, a benzoquinoid ansamycin antibiotic, has been shown to reverse the oncogenic phenotype of p60v-src transformed cells because of the inhibition of src protein tyrosine kinase. We previously demonstrated that herbimycin A displayed antitumor activity on the in vitro growth of Philadelphia chromosome-positive leukemia cells and BCR/ABL-transfected murine hematopoietic FDC-P2 cells through the inhibition of BCR/ABL protein tyrosine kinase. In this study, the transformed FDC-P2 cells were demonstrated to be tumorigenic in syngeneic DBA/2 mice. The intraperitoneal (i.p.) injection of the transformed tumor cells into DBA/2 mice induced infiltrations of abdominal organs, and then all of the mice died within time periods proportional to the cell numbers of inoculation. In mice that received an i.p. inoculation with greater than 1 x 10(5) cells, in vivo administration of herbimycin A by i.p. injection inhibited tumor formation and significantly prolonged survival time, and further, in mice inoculated with 1 x 10(4) cells, herbimycin A completely suppressed the in vivo growth of transformant FDC-P2 cells and brought about a complete remission. The present study revealed the in vivo efficacy of herbimycin A in mice bearing BCR/ABL-transfected cells.

Animals↗
PubMed1994

Perfusion of the preoptic area with muscimol or prostaglandin E2 stimulates cardiovascular function in anesthetized rats.

The effect of unilateral perfusion of the preoptic area (POA) utilizing in vivo microdialysis with the GABAergic agonist, muscimol, or prostaglandin E2 (PGE2) on cardiovascular function (heart rate, blood pressure and cutaneous blood flow) was determined in halothane-anesthetized rats. Perfusion of muscimol or PGE2 increased the heart rate, 55 +/- 6 beats/min and 69 +/- 12 betas/min, respectively (P < 0.01). Cutaneous paw blood flow tended to decrease. Blood pressure did not change in response to the perfusion of muscimol, but increased 9 mmHg in response to the perfusion of PGE2 (P < 0.01). The increases in heart rate and blood pressure were blocked by systemic administration of propranolol or adrenalectomy (P < 0.01), suggesting that these effects were due to the activation of the sympathetic innervation of the heart or adrenal gland. It is proposed that the POA provides a tonic inhibitory afferent to posterior hypothalamus neurons which regulate cardiovascular function.

Adrenal Medulla↗
PubMed1994

Phosphorylation and dephosphorylation of protein in regulating cellular function.

Phosphorylation state of cellular proteins reflects the balance between the activities of protein kinases and phosphoprotein phosphatases. The increase in cellular protein phosphorylation in response to stimuli can be achieved by either activating protein kinases and/or promoting the turnover of the protein phosphatases. This review will summarize current knowledge of the control of phosphorylation and dephosphorylation of protein in cells.

Animals↗
PubMed1994

Modulation of cysteine biosynthesis in chloroplasts of transgenic tobacco overexpressing cysteine synthase [O-acetylserine(thiol)-lyase].

Cysteine synthase [O-acetyl-L-serine(thiol)-lyase, EC 4.2.99.8] (CSase), which is responsible for the terminal step of cysteine biosynthesis, catalyzes the formation of L-cysteine from O-acetyl-L-serine (OAS) and hydrogen sulfide. Three T-DNA vectors carrying a spinach (Spinacia oleracea) cytoplasmic CSase A cDNA (K. Saito, N. Miura, M. Yamazaki, H. Horano, I. Murakoshi [1992] Proc Natl Acad Sci USA 89: 8078-8082) were constructed as follows: pCSK3F, cDNA driven by the cauliflower mosaic virus (CaMV) 35S RNA promoter with a sense orientation; pCSK3R, cDNA driven by the CaMV 355 promoter with an antisense orientation; pCSK4F, cDNA fused with the sequence for chloroplast-targeting transit peptide of pea ribulose-1,5-biphosphate carboxylase small subunit driven by the CaMV 35S promoter with a sense orientation. These chimeric genes were transferred into tobacco (Nicotiana tabacum) with Agrobacterium-mediated transformation, and self-fertilized progeny were obtained. CSase activities in cell-free extracts of pCSK3F and pCSK4F transformants were 2- to 3-fold higher than those of control and pCSK3R plants. CSase activities in chloroplasts of pCSK4F transformants were severalfold higher than those of control and pCSK3F plants, indicating that the foreign CSase protein is transported and accumulated in a functionally active form in chloroplasts of pCSK4F plants. Isolated chloroplasts of a pCSK4F transformant had a more pronounced ability to form cysteine in response to addition of OAS and sulfur compounds than those of a control plant. In particular, feeding of OAS and sulfite resulted in enhanced cysteine formation, which required photoreduction of sulfite in chloroplasts. The enhanced cysteine formation in a pCSK4F plant responding to sulfite was also observed in leaf discs. In addition, these leaf discs were partially resistant to sulfite toxicity, possibly due to metabolic detoxification of sulfite by fixing into cysteine. These results suggested that overaccumulated foreign CSase in chloroplasts could modulate biosynthetic flow of cysteine in response to sulfur stress.

Base Sequence↗
PubMed1994

Inhibition by thromboxane antagonists of airway hyperresponsiveness to histamine induced by 13,14-dihydro-15-keto-PGF2 alpha in guinea-pigs.

We studied the effect of intravenous administration of 13,14-dihydro-15-keto-prostaglandin (PG) F2 alpha on airway responsiveness to histamine and airway wall thickening in guinea-pigs. Guinea-pigs were killed and the lungs were fixed in formalin. Slides from paraffin-embedded sections of the lungs were stained and the airways that were cut in transverse section were measured by tracing enlarged images using a digitizer. Moreover, airway resistance (Raw) was determined by a pulmonary mechanics analyser and we calculated two indices, an index of airway wall thickening and the one of airway hyperresponsiveness to histamine, from changes of baseline-Raw and peak-Raw following intravenous administration of histamine before and after the intravenous administration of 13,14-dihydro-15-keto-PGF2 alpha. Intravenous administration of 10 micrograms/kg 13,14-dihydro-15-keto-PGF2 alpha for 1 h did not induce an increase of the relative thickness of the airway wall by the histological examination. In analysis of airway function, intravenous administration of 10 micrograms/kg 13,14-dihydro-15-keto-PGF2 alpha for 1 h induced airway hyperresponsiveness to histamine without airway wall thickening. Thromboxane A2 (TXA2) receptor antagonists ONO-NT-126 and ONO-8809 inhibited the 13,14-dihydro-15-keto-PGF2 alpha-induced airway hyperresponsiveness to histamine, suggesting that the effect of 13,14-dihydro-15-keto-PGF2 alpha on bronchial hyperresponsiveness is likely to be mediated through TXA2.

Animals↗
PubMed1994

Inhibition by a novel peptide leukotriene receptor antagonist ONO-1078 of airway wall thickening and airway hyperresponsiveness to histamine induced by leukotriene C4 or leukotriene D4 in guinea-pigs.

We studied the effect of intravenous administration of leukotriene (LT) C4 or LTD4 on airway responsiveness to histamine and airway wall thickening in guinea-pigs. Guinea-pigs were killed and the lungs were fixed in formalin. Slides from paraffin-embedded section of the lungs were stained and the airways that were cut in transverse section were measured by tracing enlarged images using a digitizer. Moreover, airway resistance (Raw) was determined by a pulmonary mechanics analyser and we calculated two indices, an index of airway wall thickening and the one of airway hyperresponsiveness to histamine, from changes of baseline-Raw and peak-Raw following intravenous administration of histamine before and after the intravenous administration of LTC4 or LTD4. The infusion of LTC4 or LTD4 induced an increase of the relative thickness of the airway wall in peripheral bronchi demonstrable by the histological examination. In analysis of airway function, intravenous administration of LTC4 or LTD4 induced airway hyperresponsiveness to histamine with airway wall thickening. The LTC4 and LTD4 receptor antagonist ONO-1078 inhibited these effects of LTC4 and LTD4, suggesting LTC4 and LTD4 may induce airway wall thickening and airway hyperresponsiveness through LTC4 and LTD4 receptors in the airways.

Airway Resistance↗
PubMed1994

Increased levels of blood platelet-activating factor in bronchial asthmatic patients with active symptoms.

Levels of platelet-activating factor (PAF) in blood from 12 bronchial asthmatic patients (six atopic and six nonatopic) were measured by radioimmunoassay after lipid extraction and separation by high-performance liquid chromatography. None of the patients were given disodium cromoglycate and prednisolone, and they were instructed to take only regular medications during the tests. Blood was drawn from the patients in a fasting state, and PAF levels were compared between the times when they were free of asthmatic symptoms and when they had mild spontaneous attacks. Ten (six atopic and four nonatopic) out of 12 patients, when they had the asthmatic attacks, showed higher levels of PAF than when they were free of the symptoms. Blood PAF levels of the patients with the active symptoms were significantly higher than those of normal healthy control subjects, suggesting that PAF may play a role in bronchial asthma.

Adult↗
PubMed1994

Incorporation of radioactive phosphate from adenosine triphosphate into phosphatidylinositol-4-phosphate in human peripheral blood hypodense eosinophils is less than in the normodense eosinophils.

Peripheral blood eosinophils from patients with atopic dermatitis and normal healthy controls were isolated on a Percoll gradient and incubated with [gamma 32P]ATP in the presence of Mg2+. After stopping the reaction, lipid extraction was performed with acidic medium and phospholipids were separated by thin-layer chromatography on 1% (w/v) oxalic acid-impregnated silica gel plates. In the autoradiographs considerable amounts of the radioactivity were found to be incorporated into phosphatidylinositol-4-phosphate. 32P incorporation into phosphatidylinositol-4-phosphate in hypodense eosinophils from atopic dermatitis patients was less than in normodense eosinophils from the same patients and controls.

Adenosine Triphosphate↗
PubMed1994

[Bronchial hyperresponsiveness to histamine induced by intravenous administration of 13,14-dihydro-15-keto-prostaglandin F2 alpha in guinea pigs].

Prostaglandin F2 alpha (PGF2 alpha) has been suggested to play a role in the pathogenesis of bronchial asthma. In this study, the effects of intravenous administration of 13,14-dihydro-15-keto-PGF2 alpha, a stable metabolite of PGF2 alpha, on bronchial smooth muscle in guinea pigs were investigated by measuring dynamic respiratory resistance using a formula that excludes the effects of differences in airway wall thickness. With this formula, the ratio of bronchial smooth muscle constriction by histamine can be estimated as an index of bronchial hyperresponsiveness. Administration of 13,14-dihydro-15-keto-PGF2 alpha did not induce airway wall edema. The ratio of bronchial smooth muscle constriction by histamine was significantly enhanced by the administration of 13,14-dihydro-15-keto-PGF2 alpha. Moreover, TXA2 antagonists, ONO-NT-126 and ONO-8809, inhibited the effect of 13,14-dihydro-15-keto-PGF2 alpha administration. These results suggest that 13,14-dihydro-15-keto-PGF2 alpha can be important mediators affecting bronchial hyperresponsiveness, and TXA2 may play a part in the 13,14-dihydro-15-keto-PGF2 alpha-induced bronchial hyperresponsiveness.

Administration, Oral↗
PubMed1994

Somatic afferent regulation of plasma immunoreactive glucagon in anesthetized rats.

We examined the neural mechanisms of the effect of noxious and innocuous mechanical stimulation of various segmental skin areas on the plasma glucagon concentration. Experiments were performed using chloralose- and urethane-anesthetized rats, ventilated artificially. The cutaneous stimuli of two different modalities, noxious and innocuous mechanical stimuli by pinching and brushing, were delivered to various segmental areas including the face, forelimb for forepaw, abdomen, and hindlimb or hindpaw. Blood samples were collected from the femoral artery, and plasma glucagon was measured by radioimmunoassay. Cutaneous pinching for 3.5 min of the face, forepaw, abdomen, or hindpaw increased the plasma immunoreactive glucagon (IRG), and the increase was larger following pinching of the abdmen or hindpaw than pinching of the face or forepaw. Brushing for 3.5 min of the face, forelimb, abdomen, or hindlimb did not significantly affect the plasma IRG. The increase in plasma IRG following skin pinching was abolished when both parasympathetic vagal and sympathetic nerves to the pancreas were bilaterally severed. The increase in plasma IRG was not abolished after bilateral severance of either the parasympathetic vagal or sympathetic nerves alone. These findings indicate that excitation of cutaneous nociceptive afferent information from the various spinal segments can regulate glucagon secretion from the pancreas as a reflex response, whose efferent limb is dually composed of both sympathetic and parasympathetic nerves.

Anesthesia↗
PubMed1994

Establishment and characterization of a new Ph1-positive ALL cell line (ALL/MIK) presenting bcr gene rearrangement on bcr-2 and ALL-type bcr/abl transcript: suggestion of in vitro differentiation to monocytoid lineage.

A new Ph1-positive acute lymphoblastic leukemia cell line, designated as ALL/MIK, has been developed from a patient with Ph1-positive acute leukemia. The ALL/MIK cells showed an immunophenotype of common ALL with rearranged JH and Jk genes. The ALL/MIK cells showed no M-bcr rearrangement using Southern blot analysis with either 3' or 5' M-bcr probes, but had the bcr gene rearrangement on bcr-2 within the first intron of the bcr gene. Consistent with this result, the reverse transcriptase-dependent polymerase chain reaction (RT-PCR) assay revealed that the ALL/MIK cells contained the transcript derived fusion of the first exon of bcr gene and the second exon of abl gene. Although the ALL/MIK cells were defined as early pre-B cells by immunophenotypical and genotypical analyses, they were capable of differentiating into monocytoid lineage by when cultured with TPA. Furthermore, another Ph1-positive ALL cell line, (TOM-1), was investigated for its ability to differentiate to monocytoid lineage. TOM-1 was also induced to monocytoid lineage by TPA. Thus, the present study suggested that the leukemic transformation in some Ph1-positive ALL may occur at the level of multipotential hematopoietic cells capable of differentiating towards lymphoid and myelo-monocytoid lineage.

Aged↗
PubMed1994

[Molecular study on minute alterations of the p53 and the N-ras genes in hematologic malignancies].

Minute alterations of the p53 tumor suppressor gene and N-ras oncogene were investigated in 106 samples for the p53 gene and 23 samples for the N-ras gene obtained from patients with various types of hematologic malignancies using polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) and direct nucleotide sequencing. Mobility shifts suggesting sequence alteration were observed in 9 cases (8.5%) in exons 5 through 8 containing evolutionarily highly conserved regions of the p53 gene by PCR-SSCP; missense point mutations in 3 cases (1 acute myelogenous leukemia (AML), 1 chronic myelogenous leukemia (CML) in the accelerated phase, and 1 CML in the blast crisis), silent point mutation in 1 case (malignant lymphoma), and frame shift mutations due to insertions and deletions causing stop codons in 3 cases (1 AML, 1 CML in the chronic phase and 1 acute lymphoblastic leukemia (ALL)). p53 gene alterations did not always cluster within evolutionarily highly conserved regions, and there were various base change forms in cases with p53 point mutations. p53 mutations were detected in 2 cases out of 4 cases with 17 monosomy. There was no case with p53 gene alteration in myelodysplastic syndrome (MDS) cases. Mobility shifts suggesting sequence alteration were observed in 5 cases (22%) in exon 1 and 2 of the N-ras gene by PCR-SSCP. 3 cases (1 MDS, 1 MDS overt AML and 1 ALL) were detected to contain missense point mutations. However, simultaneous mutations in both the genes were detected in only 2 cases out of 23, thereby indicating infrequent occurrence of concomitant mutation of both the genes in hematologic malignancies. Alterations of the p53 and the N-ras genes are involved in the tumorigenesis, progression and prognosis of at least some cases of hematologic malignancies, in spite that they are relatively infrequent.

Base Sequence↗
PubMed1994

[Multiple myeloma with numb chin syndrome as the initial manifestation].

The numb chin syndrome (NCS) is characterized by chin or lower lip numbness restricted to the distribution of the mental nerve (the distal trigeminal nerve). A case of multiple myeloma with polycythemia vera was diagnosed with NCS as the initial manifestation. A 73-year-old Japanese male was admitted to our hospital in April, 1993, because of paresthesia around the chin and lower lip. X-ray film showed multiple osteolytic lesions. According to serum and urine immunoelectrophoresis, lambda type Bence Jones protein was demonstrated. The bone marrow aspiration showed the normocellular marrow with 14.1% myeloma cells. He was diagnosed a suffering from multiple myeloma and was treated with melphalan and prednisolone. He is alive at present with resolution of NCS. We discussed pathogenesis, diagnosis, and treatment of NCS.

Aged↗