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K Shibuya

Publications and source records attributed to K Shibuya.

At least 19 recordsLinked to original sources
PubMed1992

Decay-accelerating factor functions as a signal transducing molecule for human monocytes.

Decay-accelerating factor (DAF) is a glycosylphosphatidylinositol-anchored membrane protein that protects cells from damage by autologous complement activation. Of the four mAb against DAF prepared in our laboratory, 1C6 completely blocked DAF function, whereas 5B2 partially blocked it. Using these mAb, we investigated whether human monocytes were activated via DAF molecules. When monocytes were incubated with 1C6 alone, glucose was consumed in significant amounts and phagocytosis of latex beads was enhanced, indicating that the monocytes had been activated. However, 1C6 did not enhance the production of monokines, TNF-alpha, and IL-1 alpha and -beta. The F(ab')2 fragment of 1C6 also activated monocytes, whereas 5B2 and the Fab fragment of 1C6 could not. To further examine monocyte activation, these cells were treated with phosphatidylinositol-specific phospholipase C. Increased glucose consumption and enhanced phagocytic activity by 1C6 were considerably reduced in monocytes treated with phosphatidylinositol-specific phospholipase C. In addition, we found that 1C6 stimulated the generation of inositol trisphosphate. These results demonstrate that the signal transmitted via the DAF molecule is capable of stimulating monocytes.

Antibodies, Monoclonal↗
PubMed1992

Morphological characteristics of a transplantable nephroblastoma (NB-Y) in F344 rats and the relation of tumour growth to hyper-reninaemia in NB-Y-bearing rats.

A transplantable tumour, designated NB-Y, was established from a spontaneous nephroblastoma in an F344 rat. NB-Y was serially passaged in syngeneic rats by subcutaneous implantation up to the 49th generation. The transplants grew into nodules with an average diameter of 5 cm and average weight of 92.9 g 4 weeks after implantation. The primary tumour and NB-Y consisted mainly of sheets or clusters of undifferentiated blastemal cells, which reacted immunohistochemically for vimentin but not for keratin. Renin-containing cells were observed in the small blood vessel walls within the primary tumour, but neoplastic cells of both primary tumour and NB-Y failed to stain for renin. Plasma renin activity was significantly higher (40.7 ng per ml per h) in transplanted rats 4 weeks after implantation compared with non-transplanted controls (28.0 ng per ml per h). Hyperplastic juxtaglomerular cells were often observed in rats bearing NB-Y. Sinusoidal dilatation was present in the liver, adrenal glands, pituitary gland and bone marrow of recipients, suggesting abnormal blood flow provoked via the renin-angiotensin system. The present study revealed the development of hyper-reninaemia in NB-Y-bearing rats, but its pathogenesis remains unknown.

Anemia↗
PubMed1992

Clinical experience in using a new type of nasal prong for administration of N-CPAP.

Nasal continuous positive airway pressure (N-CPAP) has been used in infants with decreased lung compliance for increasing the functional residual capacity (FRC), decreasing the work of breathing and improving the PaO2/PAO2 (arterial-alveolar PO2 ratio) without intubation. However, the currently available nasal prongs for administration of N-CPAP have presented some problems in fixation, and lesions to the nasal septum or nostrils might be induced by aggressive pressure intended to fix them. We would therefore like to report our experience in using a new type of nasal prong for administration of N-CPAP therapy. The nasal prongs we used were provided by Dr. Wung of Columbia University in New York, who first designed them, and have been used safely, effectively and without any complications.

Apnea↗
PubMed1992

Comparison of the incidence of intracranial hemorrhage following conventional mechanical ventilation and high frequency oscillation in beagle puppies.

Controversy exists as to whether high frequency oscillation (HFO) increases the risk of intraventricular hemorrhage (IVH) compared with conventional mechanical ventilation (CMV). We compared the risk of intracranial hemorrhage after phenylephrine-induced hypertension, combined with a hypovolemic, hypotensive insult followed by rapid volume replacement in two groups of newborn beagle puppies (one group on a piston pump HFO and the other on CMV). A total of 12 beagle puppies (6 on HFO and 6 on CMV) survived the protocol. Arterial blood gas analysis and arterial blood pressures through the study were of the same magnitude in both groups. The length of time for which the puppies remained hypertensive and hypotensive also did not vary significantly between the groups. Intraventricular hemorrhages were observed in two of six CMV puppies and two of six HFO puppies. One animal in each group had a white matter hemorrhage. Subarachnoid hemorrhages were seen in 4 animals on CMV and 3 on HFO. This study indicated that HFO does not increase the risk of any kind of intracranial hemorrhage, including IVH, in beagle puppies.

Animals↗
PubMed1992

[The advantages of laser assist in parenchyma-sparing pulmonary resection].

The advantages of laser irradiation were investigated retrospectively, using a total of 89 parenchyma-sparing pulmonary resection (PSPR) for localized lung lesions which included 42 conventional wedge resection (CWR), 8 PSPR using electrocoagulator (PE) and 39 PSPR using CO2 laser or Nd:YAG laser (PCYL). The major axes of the lesions in PNYL (25.4 +/- 10 mm) were significantly (p = 0.0387) longer than that in CWR (20.3 +/- 11.3 mm). The amount of bleeding during operation was similar in three groups. The mean value of the amount of postoperative exudation from the thoracic drains in PCYL (615 ml) was only 60 ml more than that in CWR. Bloody sputum was observed for 4.8 days in PCYL and 5.0 days in CWR, whereas 7.1 days in PE. Air leak was observed 33.3% in PCYL, 37.5% in PE, whereas 22.5% in CWR, that continued for 1.7 days (mean value) in PCYL, 1.6 days in PE and 2.0 days in CWR. Decrease (differences between preoperative and postoperative lung functions/volume of the lesions) in FVC and FEV1.0 in PCYL (mean values = 221, 158) and PE (174, 135) were less than that in CWR (339, 204). Laser assist in PSPR revealed advantages in hemostasis comparing with PE, and in parenchyma-sparing comparing with CWR. And no clear difference between PCYL and CWR in bleeding during operation, the amount of postoperative exudation and postoperative air leak. CO2 laser is reported that has higher potential in vaporization or cutting but lower ability in hemostasis comparing with Nd:YAG laser, so authors would express that Nd:YAG laser assist is most safe and effective in parenchyma-sparing lung resection.

Adolescent↗
PubMed1991

Establishment and erythroid differentiation of a cytokine-dependent human leukemic cell line F-36: a parental line requiring granulocyte-macrophage colony-stimulating factor or interleukin-3, and a subline requiring erythropoietin.

We have established a new nonlymphoid leukemic cell ine from a patient with myelodysplastic syndrome (MDS), which progressed to overt leukemia. The parental cell line and a subline derived from this line have absolute dependency on several cytokines for their long-term survival and growth. The parental line designated F-36P requires granulocyte-macrophage colony-stimulating factor (GM-CSF) or interleukin-3 (IL-3) for continuous growth, while a subline designated F-36E can be maintained in the presence of erythropoietin (Epo) alone. When these cytokines are depleted, both the parental and the subline cells die within several days, even in medium supplemented with fetal calf serum (FCS). F-36E, maintained in the presence of Epo, constitutively synthesizes hemoglobin at a significant level. F-36P, which is usually maintained in the presence of GM-CSF or IL-3, can be induced to synthesize hemoglobin when GM-CSF or IL-3 is substituted by Epo. The surface marker profile shows that the F-36P cells are positive for the leukocyte common antigen (CD45) and some common multilineage markers such as CD13, CD33, and CD34, and negative for T- and B-cell antigens and mature myelomonocytic antigens. However, some monoclonal antibodies recognizing erythroid and platelet glycoproteins react with these cells. Thus, this cell line has a multilineage phenotype, suggesting that the transformation event occurred in a multipotent stem cell. It is also evident that the F-36 cells can be induced to differentiate into the erythroid lineage in the presence of Epo. This, to our knowledge, is the first description of a human leukemic cell line that can be stimulated to synthesize hemoglobin by Epo.

Antigens, Surface↗
PubMed1991

Structural and functional analyses of glycosylation on the distinct molecules of human GM-CSF receptors.

We have previously demonstrated that granulocyte-macrophage colony-stimulating factor (GM-CSF) receptors are composed of at least two molecules of 80 and 135 kDa, which were denoted alpha- and beta-chains, respectively [Chiba, S., Shibuya, K., Piao, Y.-F., Tojo, A., Sasaki, N., Matsuki, S., Miyagawa, K., Miyazono, K. & Takaku, F. (1990) Cell Regul. 1, 327-335]. In this paper, we describe an investigation of the biochemical disparity noted between the alpha- and beta-chains of GM-CSF receptors using proteolytic and deglycosidic enzymes, and further demonstrate the potential importance of carbohydrate structures of the GM-CSF receptors using different lectins and glycoprotein synthesis inhibitors. Cross-linked alpha- and beta-chains with 125I-GM-CSF were digested by Staphylococcus aureus V8 protease and gave a different pattern. Furthermore, the size of the alpha-chain was reduced by 25 kDa by the removal of the N-linked oligosaccharides with peptidase: N-glycosidase F treatment, whereas that of the beta-chain remained unmodified by the enzyme. These results suggest that the alpha-chain of GM-CSF receptors agrees with the recently cloned low-affinity GM-CSF receptor [Gearing, D.P., King, J.A., Gough, N. M. & Nicola, N.A. (1989) EMBO J. 8, 3667-3676] having approximately 30% N-linked oligosaccharides and is biochemically different from the alpha beta-chain. By analyses using lectins, some of the oligosaccharides in the alpha-chain seem to be the complex-type and/or hybrid-type, because wheat germ agglutinin and leukoagglutinating phytohemagglutinin inhibited both GM-CSF-induced proliferation and GM-CSF binding to its receptors. Further analyses using glycoprotein synthesis inhibitors showed that N-linked processing of the alpha-chain, especially glucose removal by glucosidase I and II (whose activities are inhibited by deoxynojirimycin), appeared to be required for the expression onto the cell surface although the beta-chain expression was little affected by their inhibitors. Thus the beta-chain, probably located near the alpha-chain on the cell surface, was associated with a high-affinity class of GM-CSF receptors.

Cell Division↗
PubMed1991

IL-3 specifically inhibits GM-CSF binding to the higher affinity receptor.

The inhibition of binding between human granulocyte-macrophage colony-stimulating factor (GM-CSF) and its receptor by human interleukin-3 (IL-3) was observed in myelogenous leukemia cell line KG-1 which bore the receptors both for GM-CSF and IL-3. In contrast, this phenomenon was not observed in histiocytic lymphoma cell line U-937 or in gastric carcinoma cell line KATO III, both of which have apparent GM-CSF receptor but an undetectable IL-3 receptor. In KG-1 cells, the cross-inhibition was preferentially observed when the binding of GM-CSF was performed under the high-affinity binding condition; i.e., a low concentration of 125I-GM-CSF was incubated. Scatchard analysis of 125I-GM-CSF binding to KG-1 cells in the absence and in the presence of unlabeled IL-3 demonstrated that IL-3 inhibited GM-CSF binding to the higher-affinity component of GM-CSF receptor on KG-1 cells. Moreover, a chemical cross-linking study has revealed that the cross-inhibition of the GM-CSF binding observed in KG-1 cells is specific for the beta-chain, Mr 135,000 binding protein which has been identified as a component forming the high-affinity GM-CSF receptor existing specifically on hemopoietic cells.

Binding, Competitive↗
PubMed1991

Enhancing effect of ubenimex (bestatin) on proliferation and differentiation of hematopoietic progenitor cells, and the suppressive effect on proliferation of leukemic cell lines via peptidase regulation.

Ubenimex (Bestatin) significantly enhanced the G- and GM-CSF-induced colony formation of human bone marrow cells at concentrations of 0.001, 0.01, 0.1 and 1.0 microgram/ml (21-61% enhancement), but not at 10 micrograms/ml. Ubenimex did not influence the EPO-induced erythroid colony and burst formation between 0.0001-100 micrograms/ml. Against human and mouse leukemic cell lines, the growth-inhibitory activities of ubenimex were dose-dependently observed. Aminopeptidase activities on U937 and TF-1 cells were almost inhibited with 10 and 100 micrograms/ml of ubenimex, respectively. Cross-linking studies of 125I-GM-CSF binding to TF-1 cells demonstrated that the 150-kDa band of 2 major bands was enhanced after incubation with 0.01 microgram/ml ubenimex but decreased after that with 100 micrograms/ml, and that the 95-kDa band was not changed at any concentration of ubenimex. Change in density of the 150-kDa band on ubenimex-treated TF-1 cells was correlated with that in expression of CD10 (neutral endopeptidase) on them, whereas that in expression of CD13 (aminopeptidase N) was not changed at any concentration. These results suggest that one possible mechanism of ubenimex action in hematopoietic progenitor cells is the up-regulation of the high affinity receptor for GM-CSF and that in leukemic cell lines is suppression of amino acid incorporation via peptidase regulation.

Aminopeptidases↗
PubMed1991

Heterogeneity of cloned cell lines established from a transplantable rat malignant fibrous histiocytoma.

Four cloned cell lines, MT-7, MT-8, MT-9 and MT-10, were established from a transplantable malignant fibrous histiocytoma (MFH) of F344 rats to investigate the histogenesis of the tumor. Cells of MT-7, MT-9 and MT-10 had fine structures characteristic of histiocytes, such as numerous cell processes, many lysosomes and well-developed cytoplasmic organelles. They stained positively for histiocytic lysosomal and antigenic markers. In addition, MT-9 cells contained microfilaments and well-developed RER in their cytoplasm, suggesting that they may be facultative fibroblasts. MT-8 cells stained weakly for histiocytic markers and had scant cytoplasmic organelles. They were identified as undifferentiated mesenchymal cells. The tumors induced in syngeneic rats by inoculating MT-7 or MT-10 consisted of a mixture of the pleomorphic, myxoid and storiform types of MFH, and those by MT-9 were of the storiform type. Cells forming these tumors stained positively for histiocytic markers. Tumors induced by MT-8 consisted of undifferentiated cells negative to these stainings. The histogenesis of MFH is surmised to be related to various differentiation stages shifting from undifferentiated cells to histiocytic cells capable of acting as facultative fibroblasts.

Animals↗
PubMed1991

Renal cyst formation as a complication of primary distal renal tubular acidosis.

Morphologic studies using renal sonography and CT scanning were performed in 6 patients with primary distal renal tubular acidosis who were followed for 6 to 18 years. Nephrocalcinosis and renal cysts were identified in all patients. Multiple bilateral renal cysts were detected in 3 patients, and unilateral single or several renal cysts were detected in 3 patients. Size and number of the renal cysts in 1 patient did not change over 5 years of alkali therapy. Although the precise mechanism for renal cyst formation has not yet been established, renal cysts may be a common complication of primary distal renal tubular acidosis.

Acidosis, Renal Tubular↗
PubMed1991

Transplantable mononuclear cell leukemia in F344 rat with particular reference to nodular tumor developing at the transplant site.

A transplantable mononuclear cell leukemia (MCL) was established from spontaneous MCL in an F344 rat. In this work, we paid special attention to a nodular tumor, named MCL-YSK, developed at the subcutaneous transplant site. MCL-YSK was serially passaged in subcutaneous tissue of syngeneic rats up to the 19th generation. Transplants from MCL-YSK grew into nodules 3 cm in diameter and 11.3 g in weight 9 weeks after subcutaneous implantation. Neoplastic cells forming the nodules had azurophilic cytoplasmic granules, which ultrastructurally appeared to be lysosomes. The cells reacted positively for acid phosphatase and nonspecific esterase, but not for alkaline phosphatase, alpha-1 antitrypsin and lysozyme, nor reacted with anti-rat monocyte/macrophage monoclonal antibody and anti-rat CD-8 monoclonal antibody. They possessed Fc-receptor. Leukemic cells first appeared in the peripheral blood 6 weeks after transplantation when subcutaneous nodules reached an average diameter of one cm. Subsequently, leukemic changes progressed in recipients as MCL-YSK grew larger. The recipients died during the period from 8 to 12 weeks after transplantation, showing anemia, depression, splenohepatomegaly and lymph node enlargement. Diffuse or focal proliferation of sprinkled tumor cells was present in many organs. Hematologic changes suggestive of hemolytic anemia, elevated plasma enzymes and decreased drug-metabolizing enzymes, indicative of hepatic malfunction, were seen in transplant recipients. MCL-YSK was easily transplanted into athymic nude mice. The transplanted mice showed leukemic changes similar to those observed in rats with transplanted MCL-YSK.

Animals↗
PubMed1991

[Surgical indication for T1N2 disease: comparison of survival among resected T1N2, T2 N2 and non-resected T1 (M0) disease].

Based on the outcome of 28 patients with pathologically confirmed T1N2 disease who underwent surgical resection, we evaluated surgical indication for this stage. Twenty three patients underwent complete resection and 5 patients incomplete resection. The histologic type of tumor was adenocarcinoma in 20 patients and squamous cell carcinoma in 8 patients. The 5-year survival rate was 22% for all resected patients and 28% for completely resected patients. These survival rates were better than those (16% and 23%, respectively) in patients with T2N2 disease. However, there was no significant difference of survival among incompletely resected T1 N2, and non-resected T1 (M0) patients. Although 9 of 28 T1N2 patients survival more than 3 years, all but one patient underwent complete resection of tumor and had clinical N0 or N1 before surgery. In conclusion, surgery should be indicated only for patients with completely resectable tumor, even in T1N2 disease.

Adult↗
PubMed1991

[The therapeutic effects of itraconazole, a new triazole antifungal agent, for experimental fungal infections].

The therapeutic efficacy of itraconazole (ITZ), and oral triazole antifungal agent, was studied using several experimental fungal infections in animals. The following results were obtained: 1. ED50 values of ITZ and ketoconazole (KCZ) in a murine model of systemic candidiasis produced by intravenous challenge of Candida albicans alls were 32.9 mg/kg and 224 mg/kg, respectively. ITZ suppressed the proliferation of Candida experimentally colonized in the GI-tract of mice and/or a secondary dissemination induced by prednisolone. 2. An oral dose of 40 mg/kg/day ITZ administered for experimental pulmonary cryptococcosis in mice inhibited the fungal proliferation in the lung and the dissemination to the brain. 3. ED50 values of ITZ and KCZ for experimental systemic Aspergillus infection in mice were 103.6 mg/kg and 882 mg/kg, respectively. 4. ITZ suppressed the development of local symptoms in guinea pigs with experimental dermatophytosis. Culture studies performed on cutaneous tissues from infected sites on day-19 postinfection revealed that ITZ treatment lowered the culture-positive rate to a greater extent than KCZ-treatment. 5. Plasma concentrations of ITZ after a single dose of 100 mg/kg in mice were determined using the bioassay method: Cmax was 11 micrograms/ml and T 1/2 was 24 hours. 6. These results show that oral ITZ is highly effective in the treatment of deep-seated and superficial fungal infections produced in experimental animals.

Animals↗
PubMed1991

Genesis of pulmonary foam cells in rats with diet-induced hyper beta-lipoproteinaemia.

Hyper beta-lipoproteinaemia in rats was produced by feeding a standard diet to which was added excess cholesterol and cholic acid, with or without olive oil, for 4, 8, and 12 weeks. The beta-lipoprotein percentage in serum lipoprotein electrophoresis and lipid contents in very low density lipoprotein and low density lipoprotein fractions in these rats were significantly higher than in the control rats fed the standard diet only. The percentage of foamy monocytes (FMs) to the total number of blood monocytes (BMs) from mononuclear leucocyte fractions and percentage of pulmonary foam cells (PFCs) to the number of alveolar macrophages (AMs) from bronchopulmonary lavage fluids in the rats increased with the extension of the feeding period and were significantly higher than those in the controls. An increase in the percentage of PFCs was closely correlated with that of FMs in the rats. FMs and PFCs had cytoplasmic fine vacuoles proved to be neutral lipid and cholesterol. Histologically, PFCs made an appearance in the lungs of all the rats as early as 4 weeks after the start of feeding. The degree of the PFCs' development increased as the feeding period lengthened. When latex particles were injected intravenously into rats at feeding week 4, the percentage of latex-ingested AMs to the number of AMs in the rats was significantly higher than that of the controls at 4 and 8 days post-injection. The percentage of latex-ingested PFCs to the number of latex-ingested AMs increased with the lapse of a day after injection and was significantly higher than that of the controls at 2, 4, and 8 days post-injection. The present findings suggest that the foamy transformation of BMs and their migration into the pulmonary alveoli may be a potential mechanism of the PFCs' development in rats with hyper beta-lipoproteinaemia.

Animals↗
PubMed1991

[A case of prostatic hyperplasia in a young male].

Prostatic hyperplasia in young males is a very rare disease. A 28-year-old man was admitted to our hospital on June 24, 1989, with the chief complaints of intermittent macrohematuria and dysuria. Endoscopic examination revealed two papillary tumors in the prostatic urethra; no urinary bladder tumor was found. A transurethral resection was done for the urethral tumors. Pathological examination revealed prostatic hyperplasia. These lesions were considered ectopic prostatic tissue at first. However, imaging showed that this may in fact be prostatic hyperplasia of the apical region near the capsule. The post-operative course was uneventful and he is presently observed as an outpatient. This patient represents the seventh case reported in the literature.

Adult↗