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21.
Ota H Hayama M Nakayama J Hidaka H Honda T Ishii K Fukushima M Uehara T Kurihara M Ishihara K Hotta K Katsuyama T 《American journal of clinical pathology》2001,115(1):69-79
The specificity of monoclonal antibodies against gastric mucins (designated as HIK1083, PGM 36, and PGM 37) was studied immunohistochemically in normal, metaplastic, and neoplastic human tissues. These antibodies labeled class III mucin-producing cells identified by paradoxical concanavalin A staining in normal stomach, duodenum (Brunner gland), biliary tract, and main pancreatic duct; in mucinous metaplasia of pancreas and gallbladder; and in adenocarcinomas of stomach (90%), bile duct (80%), gallbladder (100%), pancreas (80%), lung (100% of goblet cell type adenocarcinomas), ovary (67% of mucinous carcinomas), and uterine cervix (100% of adenoma malignum tumors). Normal and neoplastic cells of esophagus, colon, salivary gland, kidney, endometrium, breast, prostate, and liver, as well as normal small intestine, lung, and uterine cervix, were all negative. The antibodies used should be valuable for the detection of class III mucin and class III mucin-producing cells in normal, metaplastic, and neoplastic tissues. 相似文献
22.
Angiogenic endothelium-specific nestin expression is enhanced by the first intron of the nestin gene 总被引:5,自引:0,他引:5
Aihara M Sugawara K Torii S Hosaka M Kurihara H Saito N Takeuchi T 《Laboratory investigation; a journal of technical methods and pathology》2004,84(12):1581-1592
Nestin is a member of intermediate filaments abundantly expressed in neural stem cells and glioblastomas. The nestin gene has four exons and three introns, and neural cell-specific expression is regulated by the second intron. We previously reported that nestin was invariably detected in the tumor endothelium in gliomas even though tumor cells were negative for nestin. In the present study, we further confirmed nestin immunostaining in tumor endothelium of a variety of common cancers, including lung, stomach, colon, and cervical carcinomas. We examined an endothelium-specific regulator using human umbilical vein endothelial cells (HUVECs) and human glioblastoma-derived U251 cells. In a luciferase reporter assay, the first intron plus 5' upstream promoter (5'UP) gave the highest activity, followed by 5'UP, and the second intron plus 5'UP. However, the assay values were much lower by HUVEC extracts than by U251 cell extracts. Although green fluorescent protein expression was positive over all U251 cells under either the first intron, second intron, or ubiquitously active CAG promoter, the fluorescence in HUVECs was limited to a few cells even under the first intron. This difference came from the growth feature of HUVECs which exhibit growth arrest by contact inhibition. We found that the nestin expression was specific to proliferative endothelium, by using proliferation markers in hemangioblastomas and in situ hybridization. Using an endothelial tube formation assay, tyrosine kinase domain-deleted VEGF receptor KDR effectively abolished the tube formation under the first intron. We suggest that the nestin expression in tumor endothelium is enhanced by the first intron. 相似文献
23.
Effects of -adrenoceptor stimulation on intracellular Ca2+ transients and tension were explored in rat ventricular muscles injected with aequorin. Adrenaline (0.05–5.0 M) and isoproterenol (0.05–1.0 M) increased the peak of twitch tension and accelerated relaxation. The former effect depended on Ca2+ concentration in Tyrode's solution ([Ca2+]o) and the stage of the experiment. Low concentrations of these drugs added to normal Tyrode's solution containing 2 mM [Ca2+]o did not potentiate twitch tension in the early stage of the experiments. These drugs increased the peak of the aequorin light signal and slightly accelerated the falling phase of the light especially the tail. Effects of dibutyryl-cyclic AMP (DB-cAMP) (0.1–5.0 mM) and 3-isobutyl-1-methylxanthine (IBMX) (0.01–0.5 mM) were qualitatively similar to those of adrenaline and isoproterenol.Isoproterenol applied at the peak of Na-deficient contracture decreased tension without significantly changing the light signal; similar results were obtained in the presence of ryanodine (1 M).The results were interpreted as follows: The increase of intracellular cAMP induced by -adrenoceptor stimulation facilitated Ca2+ uptake by sarcoplasmic reticulum (SR) and decreased Ca2+ sensitivity of contractile elements. Faster relaxation induced by cAMP was considered to be due to the decrease of Ca2+ sensitivity of contractile elements and faster Ca2+ uptake by SR. The slightly faster falling phase of light transient might be due to the faster Ca2+ uptake by SR, which predominates over the slower fall of [Ca2+]i induced by the decreased Ca2+ sensitivity of the contractile element. 相似文献
24.
25.
Tashiro M Konishi M Iwamoto T Shigekawa M Kurihara S 《Pflügers Archiv : European journal of physiology》2000,440(6):819-827
Cytoplasmic concentrations of Ca2+ ([Ca2+]i) and Mg2+ ([Mg2+]i) were measured with fluorescent indicators in CCL39 cells, a cell line established from Chinese hamster lung fibroblasts, transfected with complementary deoxyribonucleic acid (cDNA) of the Na+-Ca2+ exchanger isolated either from canine heart (NCX1) or from rat brain (NCX3). Raising extracellular [Mg2+] to 10 mM increased Mg2+ influx and the resultant change in [Mg2+]i (delta[Mg2+]i) was monitored with furaptra under Ca2+-free conditions. In control (vector-transfected) cells, delta[Mg2+]i at 45 min was similar with or without extracellular Na+ (130 mM or 0 mM) and when [Na+]i was raised by 1 mM ouabain treatment. delta[Mg2+]i in NCX1-transfected cells was attenuated significantly in the presence of 130 mM Na+, but became comparable to (or slightly larger than) that in control cells on either removal of extracellular Na+ or treatment with 1 mM ouabain. Cells expressing NCX3 showed an intermediate dependence of delta[Mg2+]i on Na+, probably reflecting a lower degree of expression of the exchanger protein. Extracellular Na+-dependent changes in [Ca2+]i (measured with fura-2 in the presence of extracellular Ca2+ and 10 microM ionomycin, a Ca2+ ionophore) were minimal in control cells, marked in the NCX1-transfected cells and intermediate in the NCX3-transfected cells. These results suggest that the Na+-Ca2+ exchanger (either NCX1 or NCX3) can transport Mg2+ and may play a role in the extrusion of magnesium from cells. 相似文献
26.
Yoshiyuki Suehara Shinji Kohsaka Takuo Hayashi Keisuke Akaike Aiko Kurisaki-Arakawa Shingo Sato Eisuke Kobayashi Sho Mizuno Toshihide Ueno Takeshi Morii Tomotake Okuma Taisei Kurihara Nobuhiko Hasegawa Kei Sano Keita Sasa Taketo Okubo Youngji Kim Hiroyuki Mano Tsuyoshi Saito 《Clinical orthopaedics and related research》2021,479(4):838
27.
Heterotransplantation of gastric adenocarcinoma, induced in dog by N-ethyl-N'-nitro-N-nitrosoguanidine (ENNG) has been attempted to nude mouse. Biopsied materials from Borrmann 3 type carcinoma, which showed signet-ring cell carcinoma at the subcardiac region of a beagle dog, were inoculated into the muscles of the hind legs of BALB/c-nu/nu nude mice. Serial transmission was obtained in 2 lives, so far 4-5 passages. The histological findings of the grafts were mainly poorly differentiated adenocarcinomas. 相似文献
28.
We studied the pathogenesis of IRBP-induced experimental autoimmune uveoretinitis (EAU) by immunohistochemical detection of various immune cells using specific monoclonal antibodies to their surface markers and adhesion molecules. The following results were obtained: (1) During each stage of EAU, CD4 positive T cells predominated over CD8 positive T cells in the retina and the uvea. (2) One day prior to the clinical onset of disease, la positive cells began to appear in the ciliary body. (3) LFA-1 and ICAM-1 were expressed on intraocularly infiltrating cells. (4) ICAM-1 was also expressed on endothelial cells of uveal and retinal vessels. In addition, ICAM-1 was expressed on ciliary body epithelium and retinal pigment epithelium, a finding which may be associated with the breakdown of the blood-ocular barrier. In conclusion, the expression of LFA-1 and ICAM-1 in EAU demonstrates that adhesion molecules, such as these, play an important role in inflammatory ocular disease in vivo. 相似文献
29.
Keiji Kushibe Sogo Iioka Kunimoto Nezu Takashi Tojo Noriyoshi Sawabata Soichiro Kitamura 《Surgery today》1995,25(4):334-337
In this study, the prognostic value of determining the nuclear DNA content of thymomas by flow cytometry was evaluated. Of a total 31 resected thymomas, 10 (32%) showed DNA aneuploidy, the presence of which was significantly correlated with an advanced clinical stage of disease. The patients with an aneuploid tumor had a poorer prognosis than those with a diploid tumor, demonstrating a survival rate of 50% at 7 postoperative years, which was considerably less favorable than that of the patients with a diploid tumor, being 100% in the same period (p<0.05). Moreover, patients with a high DNA index (DI), i.e., a DI1.5, tended to have a poorer prognosis than those with a low DI. These findings indicated that the DNA content can be an important prognostic index in patients with thymomas. 相似文献
30.
Kurihara M Kondo K Fukuhara K Toyoda M Miyata N 《Kokuritsu Iyakuhin Shokuhin Eisei Kenkyūjo hōkoku = Bulletin of National Institute of Health Sciences》1999,(117):163-165
All C-H and O-H bond dissociation enthalpies (BDE's) in catechins, (-)-epigallocatechin) were calculated by semi-empirical molecular orbital calculation using the SPARTAN program. The BDE's of benzyl hydrogens (C-2 position in catechins) were found to be quite low. This suggests that abstraction of benzyl hydrogen is crucial step for antioxidative activity. This is corroborated by the reported results of LC/MS and spectrophotometric analysis of reaction intermediates from catechins treated with AAPH. 相似文献