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T Urakawa Y Nagahata S Fukuoka T Hayashi T Takata S Matsui M Nakamoto Y Hirai K Kumagai Y Saitoh 《Nihon Geka Gakkai zasshi》1986,87(2):180-188
We prepared obstructive jaundice models in rats in order to study the mechanism of acute ulceration in obstructive jaundice centering on impediments to gastric wall blood flow and changes in gastric mucosal NA and PGE2 when the rats were subjected to water immersion restraint stress. The results were: In the obstructive jaundice 2 weeks group, when subjected to water immersion restraint stress, gastric mucosal NA reached a dried up stage from the incipient stage, causing gastric mucosal impediments at the same time, showing a significant decrease of gastric mucosal PGE2. Intragastric pH was at a similar level of excessive acidity in all groups; gastric acid is believed to be a secondary factor promoting ulceration. Gastric mucosal PGE2 showed a significant decrease coinciding with the increase in ulceration index, being a possible factor of ulceration; it is also presumed to regulate gastric wall blood flow alternatively with gastric mucosal NA. Pre-treatment with PGE2 prior to loading stress resulted in a decrease in gastric wall blood flow being significantly controlled. The administration of PGE2 brought about an improvement in gastric wall blood flow and a consequent increase in gastric mucosal NA, being judged effective for acute ulceration in obstructive jaundice. 相似文献
4.
Kazuhiko Sonoyama Haruaki Ninomiya Osamu Igawa Yasuhiro Kaetsu Yoshiyuki Furuse Toshihiro Hamada Junichiro Miake Peili Li Yasutaka Yamamoto Kazuhide Ogino Akio Yoshida Shin-ichi Taniguchi Yasutaka Kurata Satoshi Matsuoka Toshio Narahashi Goshi Shiota Yoshihisa Nozawa Hiroaki Matsubara Masatsugu Horiuchi Yasuaki Shirayoshi Ichiro Hisatome 《Hypertension research》2006,29(11):923-934
We examined the effects of angiotensin II (Ang II) on inward rectifier K+ currents (IK1) in rat atrial myocytes. [125I]Ang II-binding assays revealed the presence of both Ang II type 1 (AT1) and type 2 (AT2) receptors in atrial membrane preparations. Ang II inhibited IK1 in isolated atrial myocytes with an IC50 of 46 nmol/l. This inhibition was abolished by the AT, antagonist RNH6270 but not at all by the AT2 antagonist PD123319. Treatment of cells with pertussis toxin or a synthetic decapeptide corresponding to the carboxyl-terminus of Gialpha-3 abolished the inhibition by Ang II, indicating the role of a Gi-dependent signaling pathway. Accordingly, Ang II failed to inhibit IK1 in the presence of forskolin, dibutyryl-cAMP or protein kinase A catalytic subunits. In spite of the increased binding capacities for [125I]Ang II, Ang II failed to affect IKI in cells from spontaneously hypertensive rats (SHR). AT, immunoprecipitation from atrial extracts revealed decreased amounts of Gialpha-2 and Gialpha-3 proteins associated with this receptor in SHR as compared with controls. The reduced coupling of AT, with Gialpha. proteins may underlie the unresponsiveness of atrial IK1 to Ang II in SHR cells. 相似文献
5.
Takashi Takata Yong Lu Ikuko Ogawa Ming Zhao Zhi Yu Zhou David Mock Hiromasa Nikai 《Pathology international》1998,48(11):877-881
The calcifying odontogenic cyst (COC) presents with diverse hlstologlcal features; thus, several subclasslfl-cations have been proposed. To evaluate the slgnlficance of the various histological features and subtypes of COC from the perspectlve of proliferative activity, the proliferating cell nuclear antigen (PCNA) labellng index (LI; the percentage of positive nuclei) was assessed immunohistochemlcally in 25 cases of COC (21 benign and four malignant). All of the benign cases were of the cystic variety and further subclas-sified into non-proliferative subtype (NPS; four cases); proliferative subtype (PS; eight cases); and COC associated with odontoma (COCaO, nlne cases). The PCNA U of the mallgnant COC (65.2 ± 5.6) was slgnlflcantly higher than that of the benlgn COC (11.6 ± 9.0; P = 0.002). Non-proliferative subtype (6.8 ± 2.8) showed the lowest PCNA LI and PS (17.2 ± 11.2) the highest of among the three subtypes of benign cystic COC (P = 0.028). In nine cases of COCaO, six showed epithelial lining of the non-proliferative type as NPS and the other three had lining wlth proliferative features as PS. The PCNA LI of the latter COCaO group (14.3 ± 6.6) was significantly higher than that of the former (6.1 ± 4.3; P = 0.05), as Seen between PS and NPS. These results demonstrate that PCNA LI is a possible parameter for differentiating mallgnant COC from benign COC and, whatever the subtypes, the proliferative features In the lining are the main factor influencing the prollferatlng actlvity of COC. 相似文献
6.
Yoshihiro Katagiri Kazuhide Mabuchi Tadanori Itakura Kohji Naora Kikuo Iwamoto Yoshimasa Nozu Shun-ichi Hirai Nobumasa Ikeda Toshio Kawai 《Cancer chemotherapy and pharmacology》1989,24(4):238-242
Summary Physicochemical properties of two types of adriamycin preparation, suspensions and emulsions prepared for i.a. chemotherapy of hepatocellular cacinoma, were investigated. A suspension was prepared by dispersing adriamycin directly into the lipid contrast medium, Lipiodol, whereas an emulsion was obtained by emulsifying an aqueous solution of adriamycin into Lipiodol. The dispersibility of the drug in each preparation was examined microscopically. The chemical stability of and drug release from the preparation were determined by high-performance liquid chromatography and spectrophotometry, respectively. The suspension was then given to ten patients with primary hepatocellular carcinoma. The suspension maintained good dispersibility without coagulation of drug particles, whereas coalescence of aqueous droplets and the resultant phase separation occurred 4 h after preparation of the emulsion. Both preparations maintained the initial drug content for at least 1 week at room temperature. The release of adriamycin was more prolonged in the suspension than in the emulsion. After i.a. administration of the suspension, a selective accumulation of Lipiodol in the tumor and decrease in serum -fetoprotein (AFP) levels were found in most patients. A significant amount of adriamycin was still detected in hepatic speciments resected from two patients 1 and 2 months after treatment. These findings suggest that the adriamycin-Lipiodol suspension may be a useful preparation for targeting chemotherapy to hepatocellular carcinoma. 相似文献
7.
Tsukasa Tsunoda Toshifumi Eto Takahito Tsurifune Shigeki Tokunaga Tatsuhiro Ishii Koichi Motojima Teiji Matsumoto Tohru Segawa Kazuhide Ura Hiroshi Fukui 《Pathology international》1991,41(10):763-770
A solid and cystic tumor (SCT) was located at the head of the pancreas in a 43-year-old Japanese male, and pancreatoduodenectomy was performed on the suspicion of papillary carcinoma or cystadenocarcinoma of the pancreas. The lesion, which measured 4.5 X 4.5 X 4.0 cm, was clearly demarcated by connective tissue. The cut surface showed solid grayish-white areas with central cystic degenerative changes. The solid areas consisted of small round cells proliferating in a small solid or a pseudopapillary pattern. The tumor cells partially invaded the surrounding normal pancreatic parenchyma. Immunohistochemical studies revealed positive staining for alpha-1-antitrypsin and neuron-specific enolase, but no staining for known pancreatic hormones. Moreover, ultrastructural studies showed the absence of zymogen granules and the presence of anullate lamellae and neurosecretory granules. On the basis of these findings, a diagnosis of SCT of the pancreas was established. In order to clarify the histogenesis and biological behavior of the tumor, it is necessary to accumulate and analyze similar cases, an endeavor which in turn will contribute to the successful management of this disease. Acta Pathol Jpn 41: 763-770, 1991. 相似文献
8.
Atsushi Kikkawa Toshikazu Takata Takeshi Endo 《Macromolecular chemistry and physics.》1991,192(3):655-662
Cationic polymerization of styrene in the presence of 1-(p-methoxybenzyl)tetrahydrothiophenium hexafluoroantimonate ( 3 ) as an efficient cationic initiator was investigated. 3 was synthesized in an excellent yield by the reaction of p-methoxybenzyl bromide with tetrahydrothiophene and the subsequent exchange of bromide ions for hexafluoroantimonate ions. In the polymerization of styrene, 3 acted as a potent thermally latent initiator which initiates the polymerization at a slightly higher temperature than room temperature, although no polymerization occurs at room temperature for 30 min. 3 is a much more active initiator than the previously reported benzylsulfonium salt 1 . The enhanced activity of 3 was also confirmed in the polymerization of glycidylb phenyl ether. 相似文献
9.
Helicobacter pylori does not require Lewis X or Lewis Y expression to colonize C3H/HeJ mice 下载免费PDF全文
Takata T El-Omar E Camorlinga M Thompson SA Minohara Y Ernst PB Blaser MJ 《Infection and immunity》2002,70(6):3073-3079
Helicobacter pylori strains frequently express Lewis X (Le(x)) and/or Le(y) on their cell surfaces as constituents of the O antigens of their lipopolysaccharide molecules. To assess the effect of Le(x) and Le(y) expression on the ability of H. pylori to colonize the mouse stomach and to adhere to epithelial cells, isogenic mutants were created in which fucT1 alone or fucT1 and fucT2, which encode the fucosyl transferases necessary for Le(x) and Le(y) expression, were deleted. C3H/HeJ mice were experimentally challenged with either wild-type 26695 H. pylori or its isogenic mutants. All strains, whether passaged in the laboratory or recovered after mouse passage, colonized the mice well and without consistent differences. During colonization by the mutants, there was no reversion to wild type. Similarly, adherence to AGS and KatoIII cells was unaffected by the mutations. Together, these findings indicate that Le expression is not necessary for mouse gastric colonization or for H. pylori adherence to epithelial cells. 相似文献
10.
Suzuki K Kokai Y Sawada N Takakuwa R Kuwahara K Isogai E Isogai H Mori M 《Virchows Archiv : an international journal of pathology》2002,440(3):318-324
Helicobacter pylori induces severe neutrophilic infiltration in the lamina propria of the stomach, which leads to gastritis in humans. The possible involvement of a paracellular route for bacterial nutrients and etiologic agents that may play an important role in colonization of the bacteria and cause gastritis has been suggested. To study the functions of the paracellular barrier of gastric surface epithelium, SS1, a strain of H. pylori adapted to the murine stomach, was inoculated into the stomachs of C57BL/6 mice. At 4 months after inoculation, SS1 had achieved a high level of colonization (10(6)-10(7) colony-forming units/g tissue) associated with neutrophilic infiltration in the lamina propria of the junctional zone. Disruption of the paracellular barrier was observed in the SS1-infected stomachs, as revealed by the invasion of a lanthanum tracer into the paracellular space of the surface epithelium. Only 2% of junctions were permeable in control stomachs, whereas 72% of the paracellular barrier was disrupted in the SS1-infected gastric epithelia. Furthermore, distribution of tight junction-related molecules such as 7H6 antigen, occludin, and cortical actin was affected in the surface epithelium by SS1 infection. The linear expression pattern of occludin was disrupted and became irregular or punctuated. The 7H6 antigen accumulated as aggregates in the apical portion of the surface epithelium and cortical actin became irregular and punctuated. Taken together, these results indicate that infection by SS1 directly or indirectly caused an increase in paracellular permeability and altered the localization of tight junction-related molecules of the gastric surface epithelium. This observation suggests that the paracellular pathway may play a significant role in establishing H. pylori-induced gastritis in the clinical setting. 相似文献