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Biomedical subjects

Y Kanno

Publications and source records attributed to Y Kanno.

At least 127 records · Page 7Linked to original sources
PubMed1988

12-O-tetradecanoylphorbol-13-acetate disrupts actin filaments and focal contacts and enhances binding of fibronectin-coated latex beads to 3T3-L1 cells.

The effect of a tumor-promoting phorbol ester on the binding of fibronectin-coated beads to 3T3-L1 cells was studied to clarify the relationship between the binding of fibronectin to the cells, cell adhesion, and the organization of actin filaments. Interference-reflection microscopy revealed focal contacts of 3T3-L1 cells with the substratum. Stress fibers observed after rhodamine-phalloidin staining were well-developed in the cells. Treatment of the cells for 20 min with 12-O-tetradecanoylphorbol-13-acetate (TPA), but not with phorbol, disrupted focal contacts and caused a reorganization of stress fibers to generate actin ribbons. Treatment of the cells with TPA enhanced the binding of beads coated with human plasma fibronectin to the cells, as observed after incubation for 6 h with the beads. The TPA-induced increase in the percentage of cells with bound beads was dependent on the duration of treatment with TPA and on the concentration of TPA. Treatment of the cells with TPA also enhanced proliferation of cells in a dose-dependent manner. The enhancement of binding of the beads by TPA was suppressed by addition of an adhesion-inhibitory peptide (Gly-Arg-Gly-Asp-Ser-Pro). Treatment with TPA did not enhance nonspecific binding of beads coated with heat-denatured bovine serum albumin. Furthermore, treatment of the cells with phorbol did not enhance the binding of beads coated with fibronectin. These results suggest that TPA specifically enhances the binding of fibronectin-coated beads to 3T3-L1 cells, and that TPA-induced binding of the beads may be related to disruption of focal contacts and reorganization of actin filaments.

Actin Cytoskeleton↗
PubMed1988

Suppression of intercellular communication in acinar cells from rat submandibular gland by cholinergic and adrenergic agonists.

The effects of cholinergic and adrenergic agonists on intercellular communication in isolated acini of rat submandibular gland were evaluated using dye-coupling. Cells injected with Lucifer Yellow CH showed diffusion of the dye to their coupled neighbors under the control condition. Addition of acetylcholine (ACh) and carbachol (CCh) at concentrations higher than 10(-6) M rapidly and reversibly suppressed the dye-coupling. This effect by 10(-4) M ACh or 10(-4) M CCh was blocked by the addition of 10(-6) M atropine. The suppressive effects of 10(-4) M adrenaline and 10(-4) M noradrenaline were weaker than those of 10(-4) M ACh. Treatment with 10(-4) M isoproterenol did not inhibit the dye-coupling and the suppressive effect by 10(-4) M adrenaline was blocked by the addition of 10(-5) M phenoxybenzamine. The inhibition of dye-coupling by ACh and adrenaline was blocked by the addition of 10(-5) M verapamil, 10(-4) M W-7 and 1.5 x 10(-5) M H-7, but not by 1.5 x 10(-5) M HA1004. These results suggest that the muscarinic action of cholinergic agonists and the alpha-action of adrenergic agonists might suppress the intercellular communication of the acinar cells in the rat submandibular gland, possibly through the increase of calcium influx and the activation of protein kinase C.

Acetylcholine↗
PubMed1988

[The effect of naproxen on fever following transcatheter arterial embolization of hepatic tumors].

In the cases of trans-catheter arterial embolization (TAE) for hepatic malignancies, naproxen has been evaluated for its antipyretic effect. Each patient not given naproxen manifested a remarkable and prolonged fever despite treatment by antibiotics. In those who received an administration of naproxen, however, a significant suppression of fever was achieved (P 0.01-0.001). No remarkable influence was found on the white blood cell counts, the serum GOT and LDH levels by the naproxen. Similarly, no untoward effect due to naproxen was found on the ulcerogenicity in the gastro-duodenum. Thus, for hepatic malignancies, naproxen could be useful in the symptomatic treatment of a fever following a TAE.

Adult↗
PubMed1987

Possible involvement of reorganization of actin filaments, induced by tumor-promoting phorbol esters, in changes in colony shape and enhancement of proliferation of cultured epithelial cells.

Tumor promoters are known to induce reorganization of actin, morphological changes and enhancement of proliferation of epidermal cells in vivo. In this study, we have examined the effects of tumor promoters on these events to clarify the role played by the organization of actin filaments in the regulation of the shape and growth of colonies of epithelial cells in culture. Treatment with 12-O-tetradecanoylphorbol-13-acetate (TPA) caused a change in the shape of colonies of FL and Madin-Darby canine kidney (MDCK) cells within 6 hr. Changes in the shape of colonies were consistent with the morphological change of individual cells and the dissociation of groups of cells in the colonies. Addition of TPA also caused reorganization of actin filaments after 2 hr, and it caused enhancement of proliferation of FL and MDCK cells after 48 hr but did not cause any such changes in KB cells. However, the binding affinities of 4 beta-phorbol 12,13-dibutyrate (PDBu) to FL and MDCK cells were similar to that of PDBu to KB cells. Related tumor promoters such as phorbol 12,13 didecanoate (PDD) and mezerein caused effects similar to those caused by TPA. In contrast, nontumor promoting phorbol esters, such as 4 alpha-PDD and phorbol, had no effect. Cyclic AMP blocked the TPA-induced changes in FL and MDCK cells. These results suggest that TPA-induced reorganization of actin filaments which can be inhibited by cyclic AMP results in changes in the shape of colonies and enhancement of proliferation.

Actins↗
PubMed1987

Effects of denervation on cell-to-cell communication between acinar cells of rat submandibular salivary gland.

Communication measured by electrical cell coupling and dye transfer decreased transiently 1 day after parasympathectomy and then recovered 2 days later. Parasympathectomy decreased communication again 2 weeks later, coinciding with a decrease in the wet weight of the gland, but sympathectomy did not affect it. Thus parasympathetic nerve activity may be required for the regulation and maintenance of cell-to-cell communication in the rat submandibular gland.

Animals↗
PubMed1987

Intercellular contacts and the organization of actin filaments in cultured epithelial FL cells are altered by growth on type I collagen and treatment with 12-O-tetradecanoylphorbol-13-acetate through the modulation of interactions between cells and the substratum.

We have investigated the effects of various types of collagen and a tumor-promoting phorbol ester on intercellular contacts and the organization of actin in human amnion epithelial FL cells and mouse fibroblast 3T3-A31 cells. Our purpose was to investigate how modulation of interactions between cells and the substratum leads to alterations in intercellular contacts and organization of actin filaments. When cells were cultured on dishes coated with a solution containing type I collagen, but not type IV, changes were induced in the morphology of FL cells and their intercellular contacts. Type I collagen also caused changes in the organization of their actin filaments, although no such effects were observed with 3T3-A31 cells. In contrast, 12-O-tetradecanoylphorbol-13-acetate (TPA) caused morphological changes, dissociation of groups of cells, and reorganization of actin filaments in cultures of FL and 3T3-A31 cells. It also disrupted the sites of adhesion of FL cells to the substratum. Both type I collagen and TPA rapidly induced spreading of FL cells in the absence of serum. However, cis-hydroxyproline, known to inhibit secretion of collagen, did not suppress the TPA-induced dissociation of groups of FL cells. These results suggest that the interactions with type I collagen of epithelial FL cells, but not of fibroblastic 3T3-A31 cells, tend to disorganize cellular morphology, intercellular contacts, and actin filaments in ways similar to, but not directly related to, the effects of TPA.

Actins↗
PubMed1987

Suppression by herbimycin A of 12-O-tetradecanoylphorbol-13-acetate-induced dissociation of cells and morphological changes in cultured FL and MDCK cells.

Human amnion membrane epithelial (FL) and Madin-Darby canine kidney (MDCK) cells formed colonies which consisted of tightly packed cells. A bundle of actin filaments in the cells at the edge of the colonies ran parallel to the outline of these cells. The cells were attached to the substratum by regions which were observed as black solid lines by interference-reflection microscopy. Treatment with 12-O-tetradecanoylphorbol-13-acetate (TPA) for 24 hr induced dissociation of and morphological changes in the cells in the colonies. TPA also disrupted the organization of the actin filaments and the attachment of cells to the substratum. Addition of herbimycin A for 24 hr inhibited the TPA-induced dissociation of the cells in colonies. Treatment with herbimycin A also inhibited TPA-induced modulation of the organization of actin filaments and of the adhesion of cells to the substratum. However, herbimycin A did not inhibit the rapid spreading of cells induced by TPA in the absence of serum. These results suggest that herbimycin A inhibits the dissociation of cells and the morphological changes induced by TPA through suppression of the disruption of a bundle of actin filaments and modulation of adhesion of cells to the substratum.

Actins↗
PubMed1986

[Biliary excretion and clinical evaluation of cefoperazone in the biliary tract infections].

Biliary excretion Cefoperazone (CPZ) in a dose of 1 g was intravenously injected to each of 13 cases with obstructive jaundice. Entire bile was collected through percutaneous transhepatic cholangiodrainage (PTCD) catheter in every 1 hour for 6 hours. The mean concentration of CPZ in serum was 112.1 +/- 17.8 micrograms/ml (mean +/- S.E.) at 1 hour and 55.1 +/- 19.2 micrograms/ml at 6 hours after injection. The mean recovery of CPZ in bile within 6 hours was 1.13 +/- 0.60%. Average CPZ concentrations in bile were 64.0 +/- 45.8 micrograms/ml in the 1 hour fraction, 142.7 +/- 78.4 micrograms/ml in the 2 hours fraction and 72.2 +/- 34.0 micrograms/ml in the 6 hours fraction. Biliary excretion of CPZ was low in cases where the serum concentration of total bilirubin was high, but maximum CPZ level in bile in patients with higher serum bilirubin concentrations than 30 mg/dl was still more than 3 micrograms/ml. Clinical evaluation. CPZ was administered to 43 patients with biliary tract infections. The efficacy ratio was 88.4% (excellent and good cases) in all cases, and especially high in cases with cholecystolithiasis. But no difference in efficacy ratio was observed among cases with cholecystolithiasis, choledocholithiasis without gallstone and cases subjected to PTCD. In 10 patients examined by ultrasonography, 8 cases showed reduced diameters of gallbladder. No adverse effect of CPZ was noted in any cases. These results suggest that a fairly large portion of CPZ was excreted through bile and that CPZ is a very useful drug for the treatment of biliary tract infections.

Adult↗