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Biomedical subjects

K Toyoshima

Publications and source records attributed to K Toyoshima.

At least 55 records · Page 3Linked to original sources

Hysteroscopic selective salpingography.

OBJECTIVE: To evaluate the effectiveness of hysteroscopic selective salpingography (HSS) as a method for diagnosing the tubal proximal occlusion shown by hysterosalpingography (HSG). DESIGN: Prospective study. SETTING: Outpatient Department of Obstetrics and Gynecology, Social Insurance Saitama Chuo Hospital, Urawa, Japan. PATIENT(S): A total of 572 infertile women underwent HSG. Forty-seven of 50 women with unilateral or bilateral proximal tubal occlusion demonstrated by HSG underwent HSS. INTERVENTION(S): Hysteroscopic selective salpingography was performed for the diagnosis of tubal occlusion in cases in which the proximal tubal occlusion was shown by HSG. MAIN OUTCOME MEASURE(S): Number of patients who underwent HSS and pregnancy rate after HSS. RESULT(S): Twenty-seven (79.4%) of 34 patients with unilateral occlusion diagnosed by HSG were shown to have normal patency by HSS. Of 12 women with bilaterally normal patent tubes confirmed by HSS, 8 (66.7%) achieved normal pregnancies within 1 year. Seven (53.8%) of 13 patients with bilateral occlusion found by HSG were shown to have normally patent tubes by HSS. CONCLUSION: The simple method of HSS was clinically effective for evaluating the presence of proximal tubal occlusion.

Adult↗

Antibody-independent classical complement pathway activation and homologous C3 deposition in xeroderma pigmentosum cell lines.

Of human malignantly transformed cell lines, xeroderma pigmentosum (XP) cell lines were found to be highly susceptible to homologous complement (C): cells were opsonized by C3 fragments on incubation with diluted normal human serum. C3 fragment deposition on XP cells was Ca2+-dependent and occurred on live cells but not UV-irradiated apoptotic cells. (Ca2+ is required for activation of the classical C pathway via C1q and the lactin pathway via mannose binding lectin (MBL), and the surface of apoptotic cells usually activates the alternative C pathway.) In this study we tested which of the pathways participates in XP cell C3 deposition. In seven cell lines that allowed C3 deposition (i), Clq was shown to be essential but MBL played no role in C activation, (ii) Cls but not MASP bound XP cells for activation, (iii) no antibodies recognizing XP cells were required for homologous C3 deposition, and (iv) the alternative pathway barely participated in C3 deposition. Furthermore, the levels of C-regulatory proteins for host cell protection against C, decay-accelerating factor (DAF, CD55) and membrane cofactor protein (MCP, CD46), were found to be relatively low in almost all XP cell lines compared with normal cells. These results indicate that XP cells activate the classical C pathway in an antibody-independent manner through the expression of a molecule which directly attracts C1q in a C-activating form, and that relatively low levels of DAF and MCP on XP cells facilitate effective C3 deposition. The possible relationship between the pathogenesis of XP and our findings is discussed.

Antibodies↗

Identification and characterization of E-APC, a novel Drosophila homologue of the tumour suppressor APC.

BACKGROUND: Mutations in the adenomatous polyposis coli (APC) tumour suppressor gene are implicated in the genesis of colorectal cancers. The product of the APC gene forms a complex with beta-catenin, glycogen synthase kinase 3beta (GSK-3beta) and Axin/conductin, and induces the degradation of beta-catenin. RESULTS: We have identified a novel Drosophila homologue of APC, E-APC, which is similar to but differs in several respects from D-APC. The E-APC cDNA encodes a protein of predicted 1067 amino acids, with seven armadillo repeats, two copies of the 15-amino acid repeat, five copies of the 20-amino acid repeat, and one Axin/conductin binding site. E-APC directly interacts with D-Axin and Armadillo (Arm, the Drosophila homologue of beta-catenin) in vitro, destabilizes intracellular beta-catenin, and suppresses beta-catenin/TCF-regulated transcription in APC-/- colon cancer cells. The E-APC mRNA is ubiquitously expressed throughout all developmental stages in Drosophila. CONCLUSION: Our findings suggest that E-APC may be universally involved in the regulation of the Wingless signalling pathway by down-regulating the level of Arm in Drosophila.

Adaptor Proteins, Signal Transducing↗

Gestational choriocarcinoma whose responsible pregnancy was a complete hydatidiform mole identified by PCR analysis with new sequence tagged site primers.

We report a case where the pregnancy responsible for a gestational choriocarcinoma was not the antecedent pregnancy or the second normal term delivery, but a complete hydatidiform mole that had advanced to clinically invasive mole. This responsible pregnancy was identified by polymerase chain reaction analysis (PCR). PCR analysis was performed by using five new sets of sequence-tagged site (STS) primers on four chromosomes (chr. 1, D1S225; chr. 3, D3S1744; chr. 12, D12S1090; chr. 18, D18S849 and D18S877). The constitution of alleles of choriocarcinoma was shown to be almost identical with that of the husband on every marker. The allele patterns of choriocarcinoma on D3S1744 and D12S1090 were not observed with DNA from the patient. The band pattern originating from molar DNA was also identical with those of the husband and choriocarcinomas on D18S849 and D1S225.

Choriocarcinoma↗

Basement membrane heparan sulfate proteoglycan (perlecan) synthesized by ACC3, adenoid cystic carcinoma cells of human salivary gland origin.

The biosynthesis of basement membrane heparan sulfate proteoglycan (HSPG), known as perlecan, in ACC3 cells established from a adenoid cystic carcinoma of the human salivary gland was studied using metabolic labeling and immunoprecipitation with discriminative antibodies specific for HSPG core protein. Treatment of immunoprecipitated HSPG with HNO2, heparitinase, and chondroitinase ABC revealed that ACC3 cells synthesized HSPG molecules composed of 470-kDa core protein and heparan sulfate but not of chondroitin sulfate. The core protein was shown to contain complex type N-linked oligosaccharides by digestion with N-glycanase and endoglycosidase H. Pulse-chase experiments showed that the mature form of HSPG was formed in the cells in 30 min and released into the medium thereafter. Degradation of HSPG was also found in the chase period of 3 h. In time course experiments, HSPG was found to be synthesized maximally at day 4 after plating, deposited in the cell layer maximally at day 6, and secreted maximally at day 8. This was also confirmed by immunofluorescence, Northern blotting, and in-situ hybridization. The results indicate that ACC3 cells synthesize, secrete and degrade basement membrane type HSPG, which is analogous to those produced by other cell types, and that the biosynthesis and secretion of HSPG in ACC3 cells are strictly regulated by the cell growth, that may be reflected in the characteristic histology of adenoid cystic carcinomas.

Basement Membrane↗

High-molecular-weight fibronectin synthesized by adenoid cystic carcinoma cells of salivary gland origin.

To understand the morphogenesis of characteristic cribriform structures and the frequent invasion of salivary adenoid cystic carcinomas (ACC) along such basement membrane-rich structures as peripheral nerves, we have isolated fibronectin (FN) from the culture media of ACC3 cells established from a parotid ACC and characterized its glycosylation and alternative splicing status. FN isolated from ACC3 cells (ACC-FN) showed a molecular mass of 315 kDa in SDS-PAGE and was less heterogeneous and larger than plasma FN (pFN) or FNs from other cell sources. Differential enzymatic treatments of immunoprecipitated ACC-FN with neuraminidase, peptide-N-glycosidase F and endo-alpha-N-acetylgalactosaminidase revealed that ACC-FN was composed of a polypeptide chain of 270 kDa, with 10 kDa each of N-linked and O-linked oligosaccharide chains. Reverse transcription polymerase chain reaction (RT-PCR), in-situ hybridization, and immunofluorescence studies showed that most ACC-FNs contained ED-A, ED-B and IIICS regions in the molecules. This alternative splicing status of ACC-FN seemed to contribute to its less heterogeneous and larger molecular form. Cell attachment assay demonstrated that ACC-FN was more potent than pFN in adhesion of ACC3 cells. The results indicated that ACC-FN may function as a substrate for attachment of ACC3 cells, or that ACC3 cells trap and retain ACC-FN in their pericellular space. This isoform of FN may play an important role in the mode of invasion of ACC and the formation of stromal pseudocysts in the characteristic cribriform structure of ACC.

Alternative Splicing↗

Effect of long-term treatment with inhaled beclomethasone dipropionate on growth of asthmatic children.

The effect of long-term inhaled steroid therapy on linear growth in asthmatic children is still a point of controversy. We tried to clarify the effect of long-term treatment with inhaled beclomethasone dipropionate (BDP) on linear growth and final height of asthmatic children. Height data measured annually from 12 years (beginning at age 10 years in most patients) to 20 years of age were retrospectively collected from clinical records in 97 moderate to severe asthmatics (49 boys, 48 girls) born in 1971-1975 who were observed regularly for more than 8 years at our outpatient clinic. Data were expressed as standard deviation scores and were compared between patients treated with BDP (30 boys and 31 girls, mean daily dosages were 300-800 microg) and without BDP. Growth delay in the early period of puberty and catch-up growth in the late period of puberty was found in both patients treated with and without BDP. The age of onset of treatment with BDP inhalation had no influence on linear growth, and asthmatic children receiving optimum treatment eventually attained standard final height for their age group. Long-term treatment with inhaled BDP in conventional doses does not significantly impair linear growth in asthmatic children.

Administration, Inhalation↗

[Tuberculosis outbreak among inpatients].

The Index case, 22 year-old pregnant woman, was admitted for threatened abortion among obstetric ward in X Hospital for 17 days. Two months later, she was admitted for delivery among perinatal ward in another Y Hospital for 5 days. She produced persistent cough and sputum, when she had diagnosed pulmonary tuberculosis (TB) with sputum smear-positive and cavity on 2nd Y hospital day. By 2 years after the detection, 15 TB patients were newly diagnosed. Seven of 15 TB patients were culture positive cases and RFLP analysis of the 7 Mycobacterium TB strains demonstrated an identical banding pattern, thus confirming the spread of a unique strain. Of the 15 TB patients, seven were patients on the obstetric ward. Three were visitors. Two were infants with TB meningitis and miliary TB were not confirmed direct contact with the index case. Another two were family member and one was employee. The present outbreak emphasizes the high risk of TB transmission on obstetric and perinatal ward when the diagnosis of smear-positive pulmonary TB was delayed.

Adult↗

[Latent factors aggravating airway allergic symptom in urban population: the involvement of urban living environments].

The involvement of urban living environments in IgE-increase (atopy) and ECP-increase (enhanced eosinophil activity), the inter-relationship of IgE-increase and ECP-increase, and their involvement in developing airway allergic symptoms were studied on a population of adult nonsmoking women, in order to elucidate the latent factors aggravating airway allergic symptoms in an urban population. In our earlier study on child asthma in 1994, we examined the relationship between living environments and mite proliferation in asthma and non-asthma groups and the involvement of mite proliferation in developing atopy in the non-asthma group. The asthma group consisted of 190 children under 12 years old who had been recently diagnosed as having bronchial asthma and under the care of Osaka Prefectural Habikino Hospital. The non-asthma group consisted of 78 children under 12 years old who had been under care at Osaka Prefectural Hospital but had no present history of allergic symptom. The adult woman group consisted of 423 non-smoking women who had been diagnosed as having no allergic disease by the medical examination done at Yao City, Osaka, each March from 1995 to 1997. Individual living environments such as housing and heating styles were surveyed by questionnaire. Also, the amount of mite allergen (Dp: Dermatophagoides pteronyssinus, Df: Dermatophagoides farinae) in room and bedding dust (only in the case of children) and the concentration of continine in urine were examined as objective indicators for the load of environmental allergen and the indoor air pollution by tobacco smoke, respectively. Atopy was diagnosed according to whether Dp-specific immunoglobulin E (Dp-IgE) was present/absent (positive/negative), and ECP-increase was defined as serum ECP concentration over 10 ng/ml. The results were as follows: 1. An environment of higher humidity (dampness) causing a room to become moldy appeared to enhance mite proliferation, while heating only with an electric heater or kotatsu appeared to suppress it. 2. Living environments were involved in the development of atopy in children and adult women through the effects on mite proliferation. In the case of children, heating with oil or gas heater appeared to have a positive effect while reinforced concrete housing a negative effect, probably by effects on the immune system. However, in the case of adult women, such modification was not observed. 3. Passive smoking in adult women was related to ECP-increase. 4. IgE-increase and ECP-increase appeared to be involved in each other. 5. Among airway allergic symptoms such as cough, sputum and wheeze, atopy was involved in wheeze, and ECP-increase in cough.

Adult↗

Inhibitors of calcineurin block expression of cyclins A and E induced by fibroblast growth factor in Swiss 3T3 fibroblasts.

In Swiss 3T3 fibroblasts, growth factor-stimulated progression from G1 to S phase involves activation of the Ca2+/calmodulin-dependent serine/threonine-specific protein phosphatase 2B (calcineurin). Here we report that both cobalt and the calcium chelator EGTA, inhibitors of calcium uptake, as well as cyclosporin A and FK-506, specific inhibitors of calcineurin function, abolished fibroblast growth factor (FGF)-induced expression of cyclins A and E, but not cyclin D1. At 0.1 microM concentration cyclosporin A completely blocked FGF-induced expression of cyclins E and A and it inhibited FGF-stimulated DNA synthesis by 40%; full inhibition of DNA synthesis required 10 microM cyclosporin A. PD 98059, an inhibitor of mitogen-activated protein (MAP) kinase kinase, and hemicholinium-3, an inhibitor of FGF-induced MAP kinase activity, did not inhibit the stimulatory effect of FGF on the expression of cyclin E. On the other hand, the inhibitory effect of 0.1 microM cyclosporin A on FGF-stimulated DNA synthesis was additive with that of hemicholinium-3, suggesting that the two inhibitors acted by different mechanisms. The inhibitors of calcineurin and calcium uptake also completely blocked the stimulatory effects of lysophosphatidic acid on the expression of cyclins E and A, but not cyclin D1. The results suggest that FGF- or lysophosphatidic acid-induced transcription of cyclin A and cyclin E genes is mediated by calcineurin involving a MAP kinase-independent mechanism and that increased expression of cyclins A and E is required for the maximal stimulatory effects of these mitogens on DNA synthesis.

3T3 Cells↗

Detection of suppression of bitterness by sweet substance using a multichannel taste sensor.

A multichannel taste sensor whose transducer is composed of several kinds of lipid/polymer membranes with different characteristics can detect taste in a manner similar to human gustatory sensation. Taste information is transformed into a pattern composed of electric signals of membrane potentials of the receptor part. In the present study, it was shown that the suppression of the bitterness of quinine and a drug substance by sucrose can be quantified using a multichannel taste sensor. The present method can be expected to provide a new automated method to measure the strength of bitterness of drug substance in the place of sensory evaluation.

Chemistry, Pharmaceutical↗

Axin, an inhibitor of the Wnt signalling pathway, interacts with beta-catenin, GSK-3beta and APC and reduces the beta-catenin level.

BACKGROUND: The Wnt/Wingless signalling pathway plays an important role in both embryonic development and tumorigenesis. Beta-catenin and Axin are positive and negative effectors of the Wnt signalling pathway, respectively. RESULTS: We found that Axin interacts with beta-catenin and glycogen synthase kinase-3beta (GSK-3beta). Furthermore, the regulation of the G-protein signalling (RGS) domain of Axin is associated with the colorectal tumour suppressor adenomatous polyposis coli (APC). Overexpression of Axin in the human colorectal cancer cell line SW480 induced a drastic reduction in the level of -catenin. Interaction with beta-catenin and GSK-3beta was required for the Axin-mediated beta-catenin reduction. CONCLUSION: Axin interacts with beta-catenin, GSK-3beta and APC, and negatively regulates the Wnt signalling pathway, presumably by regulating the level of beta-catenin.

Adenomatous Polyposis Coli Protein↗

Possible role of serotonin in Merkel-like basal cells of the taste buds of the frog, Rana nigromaculata.

Merkel-like basal cells in the taste buds of the frog were examined by fluorescence histochemistry, immunohistochemistry and electron microscopy. There were about 16-20 basal cells arranged in a radial fashion at the base of each taste bud. These cells were strongly immunopositive for serotonin antiserum. They were characterised by the presence of numerous dense-cored granules in the cytoplasm ranging from 80 to 120 nm in diameter, and of microvilli protruding from the cell surface. For 4 mo after sensory denervation by cutting the gustatory nerves, all cell types of the taste bud were well preserved and maintained their fine structure. Even at 4 mo after denervation, the basal cells exhibited a strong immunoreaction with serotonin antiserum. To investigate the function of serotonin in the basal cells in taste bud function, serotonin deficiency was induced by administration of p-chlorophenylalanine (PCPA), an inhibitor of tryptophan hydroxylase, and of p-chloroamphetamine (PCA), a depletor of serotonin. After administration of these agents to normal and denervated frogs for 2 wk, a marked decrease, or complete absence, of immunoreactivity for serotonin was observed in the basal cells. Ultrastructurally, degenerative changes were observed in both types of frog; numerous lysosome-like myelin bodies were found in all cell types of the taste buds. The number of dense-cored granules in the basal cells also was greatly decreased by treatment with these drugs. Serotonin in Merkel-like basal cells appears to have a trophic role in maintenance of the morphological integrity of frog taste bud cells.

Animals↗

Establishment of ameloblastoma cell line, AM-1.

Ameloblastomas are slowly growing, locally invasive neoplasms with a potentially destructive behaviour. The molecular mechanisms that regulate the cell growth and invasion of ameloblastoma cells are unknown. Because ameloblastoma cells placed in culture have a very limited lifespan, the establishment of immortalized clones of ameloblastoma cells would aid its study. We produced an immortalized ameloblastoma cell line (AM-1) using human papillomavirus type-16. This cell line maintains epithelial cell morphology and expresses cytokeratins K8, K14, K18, K19. Furthermore, bcl-2 protein, which prevents apoptosis, is expressed. We investigated the behaviour of these cells on a collagen matrix in vitro. These cells grew in a monolayer over foci of collagen degradation and could invade the collagen gel at such sites. Since the behavior of cell line AM-1 mimics the behavior of ameloblastoma in vivo, it may be a valuable model for the study of these neoplasms.

Ameloblastoma↗

Overexpression of bcl-2 protein inhibits terminal differentiation of oral keratinocytes in vitro.

The bcl-2 proto-oncogene is a known inhibitor of apoptosis; in normal human stratified squamous epithelium, its expression is restricted to the basal cell layer. To investigate the functional role of bcl-2 protein in the process of differentiation of oral keratinocytes, bcl-2 expression vector was transfected into SCC-25 cells, which normally undergo squamous cell differentiation in vitro while expressing specific differentiation markers, e.g., keratin 10/11 and involucrin. In bcl-2 transfected SCC-25 cells, the expression of these differentiation markers was markedly suppressed. The bcl-2 proto-oncogene may play a critical role in opposing the commitment to terminal differentiation and apoptosis of oral keratinocytes.

Apoptosis↗

Identification of Merkel cells by an antibody to villin.

Merkel cells represent a population of epithelial cells in the skin and oral mucosa. Although Merkel cells are reliably distinguishable from other epithelial cells at the ultrastructural level, these cells are usually not discernible by standard light microscopy and need special techniques for their identification. Villin is an actin-crosslinking protein that is associated with the actin filament cores of brush border microvilli. In this study we show that an antibody against villin is an excellent marker of Merkel cells and their microvilli even at the light microscopic level. The surrounding keratinocytes and subepithelial connective tissue cells do not show any significant affinity for the antibody against villin. Confocal laser micrographs reconstructed from serial images 0.5 microm thick of Merkel cells that were immunostained with villin clearly reveal the three-dimensional morphology of Merkel cells and their microvilli. The presence of villin in Merkel cell microvilli lends support to the idea that these cells might have a mechanoreceptor function.

Animals↗