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K Toda

Publications and source records attributed to K Toda.

At least 235 records · Page 13Linked to original sources
PubMed1987

Reconstitution of human epidermis in vitro is accompanied by transient activation of basal keratinocyte spreading.

Frozen human cadaver skin obtained from the skin bank was thawed and incubated in serum-free medium for 1-2 days, after which the original epidermis could be removed mechanically. Transmission electron microscopic observations showed that the dermal matrix remaining behind contained intact bundles of collagen fibrils but no live cells and that a continuous lamina densa persisted in the basement membrane region. Indirect immunofluorescence analyses demonstrated linear staining of the basement membrane region by antibodies against laminin and type IV collagen and discontinuous staining with antibodies against fibronectin. Scanning electron microscopic observations revealed a normal topographical arrangement of dermal matrix papilla and interspersed crypts on the surface of the matrix. Epidermal cells placed on the dermal matrix attached in 1-2 h and spread by 24 h. After 1 week of culture the epidermis was reconstituted, at which time approximately 30% of the epidermal cells were basal keratinocytes and the remainder were more differentiated keratinocytes. A high degree of differentiation of the reconstituted epidermis was shown by the formation of hemidesmosomes along the basement membrane, the formation of desmosomes characterized by intercellular dense lines, and the presence of a cell layer containing keratohyalin granules. At various times during epidermal reconstitution, cells were harvested and tested in short-term assays for adhesion to fibronectin substrata. During the first several days there was a transient activation of basal keratinocyte spreading analogous to the modulation of keratinocyte spreading that we have observed during epidermal reconstitution in vivo.

Cadaver↗
PubMed1987

Fibronectin receptors of human keratinocytes and their expression during cell culture.

Keratinocyte attachment to fibronectin (FN) substrata was inhibited by the peptide Gly-Arg-Gly-Asp-Ser-Pro-Cys, but not by the variant peptide Gly-Arg-Gly-Glu-Ser-Pro. The RGDS-containing peptide did not inhibit keratinocyte adhesion to collagen. Keratinocyte adhesion to FN substrata also was inhibited by polyclonal anti-FN receptor antibodies originally prepared against the 140-kD FN receptors of Chinese hamster ovary (CHO) cells. Anti-CHO FN receptor antibodies did not, however, inhibit keratinocyte adhesion to collagen substrata. A monoclonal antibody designated VM-1 that was prepared against human basal keratinocytes inhibited keratinocyte adhesion to collagen but not to FN. Based on these results, we conclude that keratinocytes have distinct FN and collagen receptors. Experiments were performed to compare the expression of FN receptors on keratinocytes freshly isolated from skin and keratinocytes harvested from cell cultures. Cells harvested from keratinocyte cultures were able to neutralize the inhibitory activity of anti-CHO FN receptor antibodies and were able to attach and spread on anti-CHO FN receptor-coated substrata. Cells freshly harvested from skin, however, did not neutralize the antibodies, nor did they attach and spread on antibody-coated substrata. To learn more about the biochemical nature of the keratinocyte FN receptors, we performed immunoaffinity chromatography and immunoprecipitation experiments using the anti-CHO FN receptor antibodies. Extracts from metabolically radiolabeled, 10-d cultured keratinocytes contained FN receptors that had a 135-kD component under reducing conditions and 115- and 155-kD components under nonreducing conditions. Similar components were observed in extracts from surface-radiolabeled cells indicating that the FN receptors were expressed on keratinocyte cell surfaces. On the other hand, extracts from metabolically radiolabeled, 1-d cultured keratinocytes lacked intact FN receptors but contained a component that migrated at 48 kD under reducing conditions and 50 kD under nonreducing conditions. Because this fragment was not detected in surface-radiolabeled keratinocytes that were freshly isolated from skin, it seems likely that the fragment was located inside the cells rather than on the cell surface. A 50-kD FN receptor fragment also was observed in extracts from 10-d cultured keratinocytes if leupeptin and pepstatin were omitted from the extraction buffer. The results suggested that human keratinocytes cultured for 10 d express the 140-kD class of FN receptors, but that these receptors are not expressed on the surfaces of keratinocytes freshly isolated from skin.(ABSTRACT TRUNCATED AT 400 WORDS)

Binding, Competitive↗
PubMed1987

Properties of the membrane-bound 5'-nucleotidase and utilization of extracellular ATP in Vibrio parahaemolyticus.

Vibrio parahaemolyticus utilized ATP, ADP or AMP as the sole source of carbon. About three times higher activity of membrane-bound 5'-nucleotidase was observed in cells grown in the presence of these nucleotides than in their absence: and therefore the enzyme seems to be inducible. Since the 5'-nucleotidase activity could be measured with whole cells, the active site of this enzyme appears to be outwardly oriented. Both Mg2+ and Cl- were required for activity. Among the divalent cations tested, Mn2+ and Co2+ could replace Mg2+ to some extent, whereas Zn2+ strongly inhibited activity. Among the anions tested, Br-, I- and NO3- could replace Cl-, but SO4(2-) and CH3COO- could not. When cells were grown with ATP, Cl- was indispensable and Zn2+ strongly inhibited growth. Therefore, it is concluded that extracellular ATP and other 5'-nucleotides are cleaved by the membrane-bound 5'-nucleotidase outside the cells and that the adenosine produced is then utilized.

5'-Nucleotidase↗
PubMed1987

Activation of human keratinocyte fibronectin receptor function in relation to other ligand-receptor interactions.

Previous studies have shown that the fibronectin receptor function of keratinocytes is activated during wound healing in vivo and during cell culture in vitro. In order to study the specificity of activation in culture, two series of experiments were carried out. First, freshly isolated human keratinocytes were tested in short-term assays to determine their adhesion to several different ligand-coated substrata including fibronectin, collagen, basement membrane, concanavalin A, and wheat germ agglutinin. Second, human keratinocytes were cultured on the above substrata, and after various times, the cultured cells were harvested and retested for adhesion. We found that, compared with freshly isolated cells, cultured keratinocytes were activated more than 30-fold in their attachment to fibronectin-coated substrata but unchanged in their attachment to other ligand-coated substrata. In addition, cultured keratinocytes were activated in their capacity to spread on all ligand-coated substrata. The cells that expressed enhanced adhesiveness were found to be mostly basal keratinocytes, based on immunofluorescence staining studies. Also, basal keratinocytes attached selectively on substrata coated with fibronectin, collagen, or HR-9 basement membrane, but not on substrata coated with lectins. We propose that the activation of keratinocyte adhesiveness is a novel feature of basal keratinocytes required for reepithelialization during wound repair.

Cell Adhesion↗
PubMed1987

Activation of keratinocyte fibronectin receptor function during cutaneous wound healing.

Keratinocytes freshly isolated from unwounded skin could not attach and spread on fibronectin (FN)-coated culture dishes and could not bind and phagocytose FN-coated beads. These adhesive functions were activated, however, in keratinocytes that were isolated from healing wounds. Moreover, adhesiveness of basal keratinocytes to FN substrata was activated during epidermal cell or explant culture. Activation was specific for attachment to FN compared to other adhesion ligands, and occurred even when epidermal cells were cultured on collagen, basement membrane matrix, or lectin-coated substrata. Biochemical studies showed that keratinocytes have a 140 x 10(3) Mr FN receptor analogous to the fibroblast receptor for FN, and that this receptor is expressed in activated keratinocytes but not in keratinocytes freshly isolated from unwounded skin. The absence of FN receptors from keratinocytes in unwounded skin is not surprising since the basal keratinocytes of the epidermis are attached to a basement membrane containing laminin and type IV collagen. During wound repair, however, these cells migrate over or through a FN-coated matrix. Consequently, expression of FN receptors may be an essential feature of healing. Believing that FN is the required substratum for keratinocyte migration during wound healing, we have initiated clinical studies to determine if topical application of FN is useful as a therapy for non-healing cutaneous ulcers.

Cell Adhesion↗
PubMed1987

Mutants of Polysphondylium pallidum showing delayed modifications of glycoproteins are altered in a regulatory signal for development.

Binding of a monoclonal antibody, mAb293, to cell-surface glycoproteins of Polysphondylium pallidum is known to be blocked by L-fucose, and Fab of this antibody has been shown to inhibit intercellular adhesion of aggregation-competent cells. Mutants with delayed expression of the carbohydrate epitope, ep293, recognized by the antibody, have been shown to be retarded and altered in cell aggregation. The present study shows that ep293 is a modification of carbohydrate structure that is subject to regulation not only in mutant but also in wild-type cells; ep293 is expressed at an early stage of exponential growth in wild-type and only after 12 h of starvation in mutant PN6002. Proteins are already glycosylated before the epitope is expressed. The developmental regulation of pallidin, a lectin known to be an unglycosylated protein, was investigated in parallel with ep293 using a monoclonal antibody. Pallidin was expressed at about the same time as the carbohydrate epitope in cells of the wild-type as well as the mutant. These results indicate a regulatory signal to which various events are coupled. Induction of ep293 and expression of pallidin are two of these events, and mutants such as PN6002 are altered in the timing of the signal.

Antibodies, Monoclonal↗
PubMed1987

[Experimental analysis of the conscious structure of the sex-role-acceptance in the female adolescents: among the girl students in their final period of moratorium in Hokkaido].

The purposes of this paper are, 1) to determine the dimensions representing the structure of conscious level "sex-role-acceptance" by the female adolescents in relation to the environments within which the subjects were brought up and educated, and 2) to investigate several factors under which the conscious structure of role-acceptance have been deeply influenced: i.e., parents, sibling, boy friends in intimate terms, and others (male or female). Our data were collected from more than 1800 female students, and were subjected to multivariate analyses. The results were: 1) The following three dimensions pertaining to their sex-role-related decision-making were obtained: Biological, Social-motivational, and Self-interest. 2) The difference in the conscious-structure between the role acceptance group and the non-acceptance group was statistically significant. 3) the father-daughter interaction was significantly important in creating an active contributional will in the girls' life-plan, while the mother-daughter interaction turned out to have a rather negative influence upon their will of contribution. 4) The lack of identification with parents was sometimes compensated by their identification with others. The social importance of positive, warm support for the youngsters was clearly demonstrated.

Adult↗
PubMed1987

[Neo-adjuvant chemotherapy with UFT and adriamycin in head and neck cancer].

Thirty-one patients with head and neck cancer were administered pretreatment induction chemotherapy (so-called neo-adjuvant chemotherapy) consisting of a UFT and ADM combination. The chemotherapy consisted of ADM (0.5 mg/kg b.w.) once a week up to 3 times, and UFT (600 mg/day) every day for 20 days. Overall response rate was 37.9% (11/31), and 1 CR and 10 PR were obtained. After definitive treatment, the primary control rate was 80.6% (25/31). Sixteen primary lesions in the 31 patients were classified according to Shimosato's grading system into 1 grade IV, 5 grade III and 10 grade II b a-I. Lymph-node metastases in 5 cases were also classified. The grading of lymph-node metastases was lower than that of the primary lesions.

Adult↗
PubMed1987

Lymphangioma of the pancreas. A case report with electron microscopic observations.

A case of lymphangioma of the pancreas in a 49-year-old woman is presented. The patient noticed a left hypochondral mass, which was clinically diagnosed as a multicystic tumor of the pancreas. A partial pancreatectomy and splenectomy were performed. The surgical specimen showed a multicystic mass measuring 13 X 9 X 5 cm which occupied the anterior region of the body and tail of the pancreas. From the light and electron microscopic findings, the multicystic mass was diagnosed as a lymphangioma with cystic and cavernous features. A small glucagonoma was incidentally found in the tail of the resected pancreas. The previous literature of pancreatic lymphangiomas is reviewed and the clinico-pathologic characteristics of this tumor are discussed.

Female↗
PubMed1987

[Carcinoma of the esophagogastric junction with extension to the cervical esophagus].

A 51-year-old woman with adenocarcinoma of the esophagogastric junction (E-G J), which spread from the E-G J to the cervical esophagus, is reported. Only two cases of carcinoma in the E-G J with the extension of the tumor to the upper or middle portion of the intrathoracic esophagus have been reported in the Japanese literature in the past two decades and there have been no previous reports of E-G J carcinoma with extension to the cervical esophagus. At first, the invasion to the esophagus in our case was thought to be continuous. Histological examination, however, revealed that the tumor in the esophagus was discontinuous in some portions and that the lymph vessels were remarkably invaded. These findings suggested that the extension of the tumor to the esophagus was lymphogenous metastasis.

Adenocarcinoma↗
PubMed1986

A microcyst-overproducing mutant of Polysphondylium pallidum.

A mutant, PN6017, of the cellular slime mold Polysphondylium pallidum was selected by cell-surface labeling with a monoclonal antibody, mAb 293, and fluorescence-activated cell sorting. The antibody was directed against an L-fucose-containing epitope on glycoproteins, designated ep 293, and the mutant showed reduced and delayed expression of this epitope. PN6017 was distinguished from other mutants of this kind by extensive microcyst formation on agar plates under conditions where the wild type formed only sparse microcysts. In suspension cultures transformation of cells into microcysts was negligible in the wild type, and close to 100% in the mutant. Under these conditions microcyst formation in the mutant began at 5-7 h of starvation. At the same time expression of ep 293 and also of a developmentally regulated cytoplasmic protein, pallidin, became detectable. This coincidence in time suggests that microcyst formation in PN6017 is coupled to the same control mechanism as the two other developmentally regulated processes.

Antibodies, Monoclonal↗
PubMed1986

Immunoelectron microscopic observations in a case of linear IgA bullous dermatosis of childhood.

A 16-month-old boy exhibited vesicobullous skin lesions on the lower part of his abdomen, in his genital region, and on the buttocks and extremities. The eruptions presented small, tense bullae with or without erythematous changes of the surrounding skin, some of which clustered around the resolving lesions. Histologic examination of the eruptions showed subepidermal, ultrastructurally suprabasal laminar blister formation with infiltration of the polymorphonuclear cells and large mononuclear cells in the blister cavity. Immunoelectron microscopy revealed IgA deposits at the basilar surface of the basal keratinocytes of the lesional skin, as well as the presence of circulating IgA-class antibodies reacting to the basilar surface of the hemidesmosomes. The eruptions responded well to a combination therapy of small doses of a corticosteroid agent and a sulfonamide. There were neither clinical nor laboratory findings suggesting dermatitis herpetiformis. This case, diagnosed as linear IgA bullous dermatosis of childhood by immunofluorescence microscopy, ultrastructurally had a pathogenic site close to that observed in bullous pemphigoid.

Autoantibodies↗
PubMed1986

Differential scanning calorimetric studies on the melting behavior of water in stratum corneum.

The melting behavior of water in human stratum corneum (s. corneum) has been studied by using differential scanning calorimetry (DSC) in the temperature range from -40 degrees to 20 degrees C. The DSC thermogram was analyzed in terms of the amount of bound water and the melting temperature of water in s. corneum. Extraction of the s. corneum with the mixed solvent of chloroform: methanol (2:1, v/v) or 0.5% sodium dodecyl sulfate aqueous solution decreased the bound water content, whereas extraction with water did not change the bound water content. The melting temperature of water in the s. corneum was lowered as the water contents decreased. Extraction of the water-soluble components from the s. corneum increased the melting temperature of water when the water contents were constant. The results suggest that 20-30% of water in the s. corneum is bound water interacting strongly with the protein or lipids in the s. corneum, and the excess of water over the bound water content is unbound water solubilizing the water-soluble components such as amino acids and urea in the s. corneum. The thermodynamic theory for freezing-point depression is favorably applied to the melting temperature change of the unbound water, which implies that the water-soluble components are present as an aqueous solution in the s. corneum. Measurements of the melting-point depression of water in s. corneum provide us the quantitative information on the amount of water-soluble components in the s. corneum. This technique is a sensitive and useful tool to evaluate the hydration behavior of s. corneum.

Calorimetry↗