Search Results - (Author, Cooperation:Y. Takai)

2018-03-06

Oxford University Press

0022-0744

1477-9986

Electrical Engineering, Measurement and Control Technology

Natural Sciences in General

Physics

2011-07-30

American Association for the Advancement of Science (AAAS)

0036-8075

1095-9203

Biology

Chemistry and Pharmacology

Computer Science

Medicine

Natural Sciences in General

Physics

Adherens Junctions/metabolism ; Animals ; *Cell Adhesion ; Cell Adhesion Molecules/genetics/*metabolism ; Cell Differentiation ; Cell Line ; Coculture Techniques ; HEK293 Cells ; Hair Cells, Auditory/*cytology/*metabolism ; Humans ; Mice ; Mice, Knockout ; Organ of Corti/*cytology/*metabolism ; Phenotype ; Protein Binding ; RNA, Messenger/genetics/metabolism

1077-3118

AIP Digital Archive

Physics

Isolated diamond particles grown by chemical vapor deposition on a mirror-polished Si substrate have been studied by cross-sectional transmission electron microscopy. Focused ion beam micromachining enabled the cross-sectional specimen to be carved out precisely at the center of the particle. Atomic scale observation of the diamond/Si interface revealed the presence of an ∼3 nm thick amorphous intermediate layer including a few pits around the nucleation site of the particle. Growth mechanism and relationship between growth orientation and internal defect structure of the diamond particle are discussed. © 1995 American Institute of Physics.

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1077-3118

AIP Digital Archive

Physics

Defect structures in a homoepitaxial diamond film grown by chemical vapor deposition have been studied by cross-sectional transmission electron microscopy. Many interstitial dislocation loops are discerned in the (001) interface. The internal region grown on the (11¯1) facet comprises stacking faults and twins, while that on the (001) face contains mainly interstitial dislocation loops aligned in rows along ∼〈112〉 directions. Fe and Si impurities were detected only at the interface by analytical electron microscopy. The origin of the defects is briefly discussed. © 1996 American Institute of Physics.

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1077-3118

AIP Digital Archive

Physics

We have investigated surface morphology of YBa2Cu3O7−y thin films prepared by chemical vapor deposition (CVD) using liquid metalorganic (MO) sources on MgO(100) single crystalline substrates by atomic force microscopy (AFM). An abrupt change in the terrace width was observed at the deposition temperature of around 750 °C. An anomalous decrease in the efficiency of incorporation of the yttrium component into the film was also found above the same temperature. It suggests that the appearance of liquid phase on the growing surface and the growth mode change from the conventional vapor growth to the VLS (vapor–liquid–solid) growth mode at this temperature. © 1996 American Institute of Physics.

Electronic Resource

1365-2222

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Background Increased vascularity in airway mucosa is a distinctive feature of airway remodelling in asthma. While corticosteroids have proved most effective in modifying airway inflammation, the effect of inhaled corticosteroids on increased airway mucosal vascularity in asthmatics has been little studied.Objective We examined the effect of inhaled corticosteroid on airway vascularity in bronchial biopsy specimens taken from asthmatic patients.Subjects and methods We studied bronchial biopsies from 28 asthmatic patients before and after treatment with inhaled beclomethasone dipropionate (BDP) 800 µg/daily, or placebo, for 6 months in a double-blind manner. Biopsy specimens were evaluated for number of vessels and percentage of area occupied by vessels, using computerized image analysis after staining for type IV collagen in vessel walls. Specimens were also examined for extent of collagen III in the subepithelial basement membrane. In addition, we compared asthmatic specimens with biopsy specimens taken from non-asthmatic control subjects.Results There was a significant increase in number of vessels (P 〈 0.01) and percent vascularity (P 〈 0.001) in the submucosa of asthmatic patients compared with control subjects. After 6 months of treatment, we observed significant improvements in forced expiratory volume in 1 s (FEV1), FEV1% and airway responsiveness (P 〈 0.05, each) in the BDP treatment group compared with the placebo group. This was accompanied by significant decreases in both vessel number and percent vascularity in the airways of BDP-treated patients (P 〈 0.05, each). We also observed a significant correlation between change in percent vascularity and change in collagen III thickness in the BDP-treated patients (rs = 0.90, P 〈 0.001). Furthermore, the change in percent vascularity was inversely correlated with both FEV1 (rs = −0.49, P 〈 0.05) and airway responsiveness (rs = −0.36, P 〈 0.05).Conclusion These findings suggest that inhaled corticosteroid treatment of asthma reduced airway wall vascularity during airway remodelling.

Electronic Resource

1600-0714

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

To evaluate the participation of myoepithelial components in pleomorphic adenomas, an immunohistochemical study was carried out using monoclonal antibodies to vimentin. Of a total of 80 cases, 50 tumors gave positive staining, 5 tumors very slight, and 25 tumors negative staining for vimentin. Localization patterns for vimentin were divided into 3 classes: 1) vimentin staining in fibrous stromal tissue; 2) variable intensities of vimentin staining were found in the outer layers of tumor cells in tubuloductal structures (some of which were spindle cells connected to modified myoepithelial cells which also gave variable vimentin staining); and 3) modified myoepithelial cells and chondroidlike cells displayed strongly positive staining for vimentin. Typical histologic features of pleomorphic ademomas, i.e., tubulo-ductal or duct-like structures were characterized by positive vimentin staining in outer tumor cells and by a positive keratin reaction in the luminal tumor cells. In tumors devoid of stromal connective tissues and the near absence of well-developed, or modified myoepithelial cells, vimentin staining was absent.

Electronic Resource

1600-0714

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Duct-ligated submandibular and sublingual glands of rats were evaluated immunohistochemically for changes in keratin (MoAb 1164), actin, S-100 protein and rat-EGF (rEGF). Normal salivary glands were reactive for keratin, S-100 protein and rEGF in the granular convoluted tubule (GCT) and duct cells, and for actin in the myoepithelium. Submandibular glands showed a marked reduction of S-100 protein and rEGF staining following duct ligation, and no increased staining of proliferating epithelial cells of the late stage in duct ligated glands. Sublingual glands revealed no marked changes for actin staining in myoepithelial cells, irrespective of atrophic changes occurring in acinar and duct cells after duct ligation. Immunohistochemical patterns differed for each type of gland; changes associated with the obstructive lesion were more prominent in the submandibular gland.

Electronic Resource

1600-0714

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Peroxidase-conjugated lectins were used for the histochemical detection of carbohydrates in experimental carcinomas of mouse submandibular glands. Induced carcinomas, 43 lesions from 25 cases, were examined histoehemically with galactose-binding leetins (PNA and RCA-I), N-acetyl-galactosamine-binding leetins (DBA and SBA), a fucosc-binding lectin(UEA-l), and a N-acetyl-glucosamine-binding lectin (WGA). In non- or slightly keratinized squamous-cell carcinomas, the lectin binding of PNA, RCA-1, DBA, SBA. and WGA was weak in tumor epithelia, and UEA-1 binding was slight. In highly keratinized squamous-cell carcinomas, lectin binding was increased in tumor epithelia, but no reaction was noted in completely keratinized regions. Desquamated materials in lumens of tumors gave an intense stain with leetins. Stromal connective tissue, including collagen fibers and basement membranes stained intensely. Lectin binding to submandibular carcinomas was different from binding to granular convoluted tubules and the striated ducts of the normal submandibular gland.

Electronic Resource

1600-0765

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Histochemical demonstration of lectin-binding sites and keratin peptides in gingival epithelia was reported and differences in staining and distribution were compared to inner and outer gingival epithelia.Gingival epithelia on the outer side exhibited zonal or regional distributions of lectin-binding, and the cytochemical staining was generally found in the cell coat and intercellular materials. Keratin protein was found frequently in the spinous cell, infrequently in the basal cells, and not at all in the superficial layer. The sugar residues in the cell coat of gingival epithelia probably were mannose, galactose, N-acetyl-galactosamine, and N-acetyl-glucosamine.The inner side of the epithelia, crevicular, and pocket epithelia were characterized by irregular and incomplete staining for lectins. These epithelia also displayed less keratin staining compared to the outer gingival epithelia. These findings suggest the possibility of depolymerization of glycosaminoglycans in the cell coat by enzymes of either pocket bacterial origin or host tissue origin.

Electronic Resource

1600-0714

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

The cell membrane carbohydrate components of 10 simple (follicular and/or plexiform pattern) and 5 acanthomatous ameloblastomas, one plexiform unicystic ameloblastoma, one soft tissue ameloblastoma and 11 odontogenic keratocysts were studied in paraffin-embedded tissues using horseradish peroxidase-conjugated lectins. The presence of glucose and mannose was demonstrated by intense labelling with Concanavalin ensiforme (Con A) in 73% of the ameloblastomas examined, while periodate oxidation of the specimens prior to Con A (PA/Con A) stained 53% of the cases. Ameloblastomas did not express receptors for Triticum vulgaris (WGA), Erythrina chrystagalli (ECA), Arachis hypogea (PNA), and Ulex europaeus (UEA-1). The plexiform unicystic ameloblastoma and the soft tissue ameloblastoma examined showed the same cell membrane glycoproteins as the simple and acanthomatous ameloblastomas. Forty-five per cent of the keratocysts demonstrated Con A reactivity from the basal to the keratinized layer, while 72% of these specimens showed positive PA/Con A reactivity from the parabasal to the keratinized layer. Staining with WGA, ECA, PNA, and UEA lectins also revealed the presence of N-Acetyl-glucosamine and fucose oligosaccharides in the plasma membrane of basal, spinous and keratinized cell layers of the odontogenic keratocysts. The distinct cell surface carbohydrate composition of the ameloblastoma and odontogenic keratocyst may be responsible for the differences in biological behavior in these conditions.

Electronic Resource

1600-0714

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Immunohistochemical detection of keratin proteins in duct-ligated submandibular glands (SMG) was carried out in mice and rats with or without testosterone administration. Keratin staining in normal salivary glands was limited to the striated duct (SD) and excretory duct (ED) cells and was usually lacking in granular convoluted tubule (GCT) cells. Following duct-ligation, the epithelia of intercalated ducts (ICD), degranulated tubules, duct-like structures, and dilated striated and excretory ducts showed positive keratin staining, usually in their luminal aspects. The concentration of keratin was proportional to the degree of degranulation of the GCT cells. The duct-ligated SMGs in animals with testosterone treatment showed a comparatively higher number of granules located in the GCT cells, and degranulation was slight. Keratin staining in hormone-treated duct-ligated glands also occurred in ductal segments to a slight degree. Keratin was also detected in degranulated tubules, and its concentration was increased in duct-like structures, whereas staining for EGF and NGF was decreased in degranulated tubules and lacking in duct-like structures.

Electronic Resource

1600-0714

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Histopathologic observations of 9,10-dimethyl-1,2-benzanthracene (DMBA)-induced tumors in the mouse submandibular glands arc reported using cryoprobe treatment. The experimental animals were divided into 2 groups; one received a carcinogen injection into the normal submandibular gland, and the oilier was injected with DMBA on the Mill day following cryosurgery of the gland using a 60°C cryoprobe. Pathologic findings were classified as premalignant lesions or squamous-cell carcinomas with varying degrees of keratinization, fibrosarcoma and mixed carcinoma. There was also one case each of malignant pleomorphic adenoma and cystic adenoma. Tumor incidence was nearly the same in the 2 groups. Most of the carcinomas and sarcomas in the submandibular gland were induced during the 12th and 17th weeks. DMBA application during the proliferating stage which followed the cryosurgery did not enhance epithelial-tumor induction. During submandibular gland carcinogenesis, alterations in the granular convoluted tubule cells suggests they were the initial target cells undergoing malignant transformation. Squamous-cell carcinomas with varying degrees of keratinization were induced following squamous metaplasia in duct-like structures or multicystic lesions.

Electronic Resource

1600-0714

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

An immunohistochemical survey of the distribution of keratin was studied in chemically induced carcinomas of the submandibular glands of mice. Initial signs of premalignant changes were degranulation of granular convoluted tubule cells and deposition of keratin protein in small limited areas of the degranulated cells. There was a gradual increase in the area showing keratin staining in altered tubule cells. Duct-like and cystic structures stained intensely for keratin, as did squamous metaplastic epithelial cells. Induced carcinomas were variably keratinized. Basal layers of cells of squamous-cell carcinomas displayed weak keratin staining, and spinous tumor cells and parakeratotic tumor cells showed somewhat increased levels of keratin staining. Some desquamated keratotic tumor cells stained intensely for keratin. Just as the localization of epidermal and nerve growth factors and lectin-binding histochemistry have been used in studying tumorigenesis in the mouse submandibular gland, immunohistochemically detected keratin proved to be a useful marker of tumor cells of ductal segment origin.

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1600-0714

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Lectin binding patterns of Con A. PNA, SHA, DBA, WGA, RCA-1 and UEA-1 were tarried out in duct-ligated submandibular glands (SMGs) of rats that diplayed acute degenerating changes Lectin staining was also related to histologic changes. Proliferating epithelial cells which were probably derived from intercalated duet cells showed a strong SBA and WGA staining on the 3rd day. Duct-like and cystic structures appeared on the 7th day and staining by PNA, SBA. WGA. RCA-1 and Con A was described In mice. lectin binding after duct ligation appeared similar to the rat In the long-term observation of mice SMGs. acinar cell regeneration occurred between the 2lsl and 42nd days and they stained strongly for DBA.

Electronic Resource

1600-0714

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Immunohistochemical defection of epidermal growth factor (EGF) and nerve growth factor (NGF) was carried out in duct-ligated submandibular glands (SMG) of mice with or without testosterone treatement. High levels of EGF and NGF were limited to granular convoluted tubule (GCT) cells in normal adult male mice, and reduced levels were evident in the female. After duet ligation, EGF and NGF stainings began to decrease on the 2nd or 3rd day, and by the 10th day, no staining was detectable. Decreasing levels of EGF and NGF following duct ligation, were more pronounced in the male SMG than in the female. Testosterone administration before ligation resulted in decreased EGF and NGF levels of staining; however, staining of sections on the 1st and 3rd day was a little stronger than comparable stained sections of untreated mice. In contrast, testosterone administration after duet ligation showed GCT cells of normal size with some degranulation at 10 days and irregular staining of growth factors with varying degrees of degranulation at 14 days. Histochemical staining for EGF and NGF in this group was marked, as in the normal, until the 10th day with decreasing reactions by the 14th day.

Electronic Resource

1600-0714

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Complex carbohydrates in premalignant lesions of mouse submandibular gland tumors were examined by the lectin-peroxidase conjugate method. Peroxidase-conjugated lectins of PNA, RCA-1, DBA, SBA, UEA-1 and WGA were used to detect specific sugar residues of complex carbohydrates in premalignant lesions during experimental carcinogenesis. Marked reduction of PNA and SBA bindings occurred in duct-like structures and cystic lesions which were transformed from granular convoluted tubule cells. Premalignant lesions bound slightly to PNA, RCA-1, DBA, SBA and WGA and manifested increased UEA-1 binding. Squamous metaplastic epithelia of premalignant lesions manifested increased binding to PNA, RCA-1 and SBA as compared to those of duct-like structure and cystic epithelia.

Electronic Resource

1600-0714

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

The lectin, Concanavalin A(Con A) has been used to localize specific sugar residues (D-glucose, D-mannose and D-fructose) in premalignant lesions and squamous-cell carcinomas induced following cryosurgery of the mouse submandibular gland. The original Con A-horseradish peroxidase (HRP) technique as well as its combination with periodate oxidation and subsequent reduction by borohydrate were used to compare the epithelial elements during submandibular gland carcinogenesis. Granules in the granular convoluted tubule cells which were weakly reactive to the Con A-HRP method were not present in the premalignant duct like structures. The epithelium of premalignant lesions, duct-like structures, multicystic lesions, and squamous-cell carcinomas were positive for the cell-surface and intercellular substances; and basement membranes and stromal fibers were also positive. The results indicated that throughout malignant transformation of the ductal segments, premalignant epithelia lost Con A-HRP-staining granules and that Con A-binding patterns in induced squamous-cell carcinomas were similar to those found in squamous-cell epithelium.

Electronic Resource

1365-2133

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Summary Background A novel cell–cell adhesion system that consists of nectin and afadin has been identified at cadherin-based cell–cell adherens junctions. Nectin is a Ca2+-independent homophilic and heterophilic cell adhesion molecule that belongs to the immunoglobulin superfamily. Nectin has recently been shown to serve as an α-herpesvirus entry and cell–cell spread mediator. In spite of the ubiquitous expression of nectin-1α, its detailed localization in human skin has not been examined so far. Objectives To investigate the localization of nectin-1α in normal human skin and the alteration of its expression in malignant skin tumours. Methods Immunohistochemistry was employed to determine the expression of nectin-1α and other adhesion molecules. Results We detected nectin-1α in normal human epidermis, follicles and eccrine ducts. Nectin-1α was colocalized with E-cadherin at cell–cell adherens junctions of the epidermis. The concentration of the nectin–afadin system at cell–cell adherens junctions was reduced in the early stage of malignant transformation of keratinocytes, such as in basal cell carcinomas and squamous cell carcinomas, where the cadherin–catenin system was preserved. Nectin-1α at cell–cell adherens junctions was reduced in human epithelial cancer cells located at the advancing border of the tumour. Conclusions Our results showed that nectin-1α is located at cell–cell adherens junctions in human skin and that reduction of nectin-1α at cell–cell adherens junctions may be involved in the invasion of squamous cell tumours.

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0006-291X

[abr] BSA; bovine serum albumin ; [abr] G protein; GTP-binding protein ; [abr] GDI; GDP dissociation inhibitor ; [abr] GDS; GDP dissociation stimulator ; [abr] SDS-PAGE; sodium dodecylsulfate-polyacrylamide gel ; [abr] TBS; Tris-buffered saline

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Biology

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