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21.
Hiroko Koizumi Chikako Yasui Torn Fukaya Tetsuo Ueda Akira Ohkawara 《Experimental dermatology》1994,3(1):40-44
Abstract Substance P is a neuropeptide which is present in peripheral C nerve endings and released from them. Free nerve endings of C nerve are present in human epidermis. The effects of substance P on the transmembrane signaling system of pig epidermal sheets were previously reported. In these studies, a small amount of cells other than keratinocytes contaminated the epidermal sheets and the species difference from human was also noticed. Therefore we investigated the effects of substance P on cultured normal human epidermal keratinocytes. Alteration of intracellular free calcium (Ca2+) in single living keratinocytes was studied using an inverted fluorescence microscope and Ca2+ -sensitive dye, Fura 2-AM. Treatment of normal human epidermal kertinocytes with substance P resulted in an increase in inositol 1,4,5-trisphosphate and in intracellular Ca2+. Substance P inhibited DNA synthesis of the keratinocytes in a dose-dependent manner. These results are consistent with the view that substance P stimulates phosphatidylinositol-4,5-bisphosphate hydrolysis of human keratinocytes, resulting in inositol 1,4,5-trisphosphate-Ca2+ signal. 相似文献
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23.
K Sakakibara K Mizuno T Kano M Ohta Y Tomita G Yoshio Y Tokuhashi Y Nishida E Okamoto M Hori 《Gan no rinsho》1986,32(14):1841-1848
The pharmacokinetics and metabolism of carmofur (HCFU) were studied. Sixty-six patients were administered 100 mg of HCFU orally, and the plasma levels of the HCFU fraction (HCFUf) and 5-fluorouracil (5-FUra) were determined at 0, 1, 2, 4 and 6 hours. The average half-life of HCFUf and 5-FUra were 1.05 and 1.31 hours, and the average areas under the curves (AUC) of the plasma concentration were 6.51 hr X mcg/ml and 0.46 hr X mcg/ml, respectively. Surgical specimens of the tumors were obtained about three hours after the administration and assayed for HCFUf. 5-FUra fluorodeoxyuridine-monophosphate (FdUMP), deoxyuridine-monophosphate (dUMP), total thymidylate synthetase (TS total), and non-FdUMP-bound free enzyme (TS free). The TS inhibition rate (IR) was calculated by the follow method: IR = (TS total-TS free)/TS total X 100 levels of the TS total varied from not-detected (less than 0.10 pmol/g) to 20.5 pmol/g. The average FdUMP: dUMP ratio was 3.44 X 10(3), However, more than 80% inhibitions of TS were observed in nine cases (21.4%). The correlation indicates between TS IR and tissue FdUMP level or FdUMP: dUMP ratio were 0.57 and 0.62 in ovarian malignancies respectively. No significant correlations were observed between TS inhibition and levels of tissue 5-FUra or AUC of 5-FUra. 相似文献
24.
25.
Hidemi Kaname Toshio Yoshihara Yuji Yaku Tetsuo Ishii 《Medical Electron Microscopy》1993,26(2):99-104
Primary squamous cell carcinoma of the submandibular gland is a rare tumor. In this report, the histological and ultrastructural
features of a case of primary squamous cell carcinoma arising in the left submandibular gland is presented. Light microscopically,
the tumor consisted of well differentiated keratinizing squamous cell nests. Ultrastructurally, the tumor cells were oval
or spindle-shaped, and several tumor cells had intracytoplasmic desmosome-like structures, resembling intercellular desmosomes.
The majority of the tumor cells contained a large number of intermediate filaments (tonofilaments). Intercellular desmosomes
were well developed. No secretory granules were found. These ultrastructural features may enable us to distinguish primary
squamous cell carcinoma from mucoepidermoid carcinoma which is often misdiagnosed as squamous cell carcinoma. 相似文献
26.
Development of new immunoradiometric assay for CA 125 antigen using two monoclonal antibodies produced by immunizing lung cancer cells 总被引:4,自引:0,他引:4
Mihoko Kunimatsu Keigo Endo Tetsuo Nakashima Toshikazu Awaji Tsuneo Saga Yuji Watanabe Yasutaka Kawamura Hitoya Ohta Mitsuru Koizumi Harumi Sakahara Junji Konishi Shingo Fujii Takahide Mori Kanji Torizuka Yoichiro Matsuoka Tsuyoshi Nakagawa Nobuo Yamaguchi 《Annals of nuclear medicine》1988,2(2):73-79
CA 125 is an antigen associated with non-mucinous epithelial ovarian cancer, which is defined by OC 125 antibody developed by immunizing ovarian cancer cells. We have produced two monoclonal antibodies, 130-22 and 145-9, by using the human lung adenocarcinoma cell line PC-9. Both 130-22 and 145-9 antibodies recognized CA 125 antigen. However, the binding sites seemed to be separate from those of OC 125. Testing by 9 immunoradiometric assays (IRMA), using different combinations of the 3 monoclonal antibodies 130-22, 145-9 and OC 125 demonstrated that the best standard curve for detecting CA 125 could be obtained by a "simultaneous sandwich" assay based on a mixture of 125I-labeled OC 125 and 130-22 or 145-9 coated beads. One-step IRMA, using 130-22 as a tracer and 145-9 as an immunoadsorbent, also showed good reproducibility and sensitivity for measuring CA 125. Antigens were detectable in the culture supernatants of PC-9 cells and 5 of 6 ovarian cancer and endometrial adenocarcinoma cells. These results indicate that one-step IRMA using 130-22 and 145-9 is useful for detecting CA 125 antigen. 相似文献
27.
Possible involvement of arachidonic acid metabolism in phenobarbital promotion of hepatocarcinogenesis 总被引:8,自引:4,他引:4
Denda Ayumi; Ura Hitoshi; Tsujiuchi Toshifumi; Masahiro Tsutsumi; Eimoto Hiroyuki; Takashima Yoshiharu; Kitazawa Shunji; Kinugasa Tetsuo; Konishi Yoich 《Carcinogenesis》1989,10(10):1929-1935
The effects of inhibitors of arachidonic acid metabolism andantioxidants on the rat liver tumor promotion activity of phenobarbital(PB) were assessed using the enzyme-altered focus as the end-pointlesion. Fischer 344 male rats were initiated with N-nitrosodiethylamine(200 mg/kg) and then divided into five groups placed on basaldiet, diet containing 0.05% PB, diet containing 0.05% PB plus0.75%, 1% or 1.5% levels of various inhibitors of arachidonicacid metabolism or antioxidants, or diet containing 1% or 1.5%inhibitors or antioxidants alone for 10 weeks, and then killed.-Bromo phenacyl bromide, an inhibitor of phospholipase A2 significantly inhibited the promotion activity of PB at dose levelsof 0.75% and 1.5%, reaching plateau at 0.75%. Both quercetin,an inhibitor of lipoxygenase, and morin, a dual inhibitor oflipoxygenase-cyclooxygenase, significantly reduced the promotionactivity of PB at the 1.5% but not 0.75% dose levels. Moreover,acetylsalicylic acid, an inhibitor of cyclooxygenase dose-dependentlyinhibited the promotion activity of PB. Among the antioxidantsinvestigated, vitamin E did not affect, but n-propyl gallateand ethoxyquin exerted a dose-dependent inhibition of PB promotion.These results are strongly suggestive of an involvement of phospholipaseA2 lipoxygenase and cyclooxygenase arachidonic acid metabolicpathways in the mechanisms underlying PB enhancement of hepatocarcinogenesis. 相似文献
28.
Kitajima T Kanbayashi T Saito Y Takahashi Y Ogawa Y Sugiyama T Kaneko Y Aizawa R Shimizu T 《Neuroscience letters》2004,355(1-2):77-80
It is known that benzodiazepines have a hypotensive effect, but the mechanism has not been well elucidated yet. To clarify whether this effect is due to central or peripheral mechanism, we administered 5 mg of diazepam or saline intravenously to healthy volunteers and assessed the change in blood pressure, heart rate, muscle sympathetic nerve activity and heart rate variability. After diazepam administration, systolic and mean blood pressure decreased significantly. Muscle sympathetic nerve activity was also significantly reduced but heart rate did not change, whereas the variables of spectral analysis of heart rate variability did not show significant change. We concluded that the hypotensive effect of diazepam in human is mainly due to the central mechanism. 相似文献
29.
Takaaki Ohmori Ryo Tabei Norimasa Arita Mari Kondo Tetsuo Kozawa Yoshinori Chikamori Norifumi Ueda 《Pathology international》1983,33(5):999-1007
This report concerns a case of solitary extramedullary plasmacytoma of the left submandibular lymph node in a 56-year-old man. The tumor showed monoclonal proliferation of abnormal plasma cells which revealed highly positive stainings of both methylgreen pyronin and kappa light chain using the immunoperoxidase technique in the cytoplasms, and further revealed massive'.amyloid'deposits in the stroma, which suggested the possibility of sequential amyloid formation upon the secretion of paraprotein by tumor cells. 相似文献
30.