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71.
Irritant-induced cyclooxygenase-2 is involved in the defense mechanism of the gastric mucosa in mice 总被引:2,自引:0,他引:2
Miyake K Tsukui T Wada K Tatsuguchi A Futagami S Hiratsuka T Shinoki K Iizumi T Akamatsu T Sakamoto C Kobayashi M 《Journal of gastroenterology》2002,37(3):164-171
Background. Endogenous and exogenous prostaglandins (PGs) have been shown to contribute to reducing the gastric injury caused by irritants
given subse-quently. The aim of this study was to clarify whether cyclooxygenase-2 (COX-2) protein induced by pretreatment
was involved in the prevention of subsequent ethanol-caused gastric injury in mice. Methods. Mice were pretreated with acidified ethanol or saline and then COX-2 protein expression in the stomach was immunohistochemically
determined every 8 h. Mice were administered 95% ethanol 24 h after the acidified ethanol pretreatment, and gastric mucosal
damage was evaluated macroscopically and histologically. The effects of NS-398 or indomethacin on the 95% ethanol-caused damage
were also examined. Results. Acidified ethanol pretreatment induced COX-2 protein expression in lamina propria macrophages of the gastric mucosa, with
a peak level 24 h after the pretreatment. The 95% ethanol treatment caused gastric mucosal damage. The degree of the damage
was not different between mice pretreated with acidified ethanol and those pretreated with saline. However, NS-398 aggravated
the ethanol-caused damage only in mice pretreated with acidified ethanol, while indomethacin aggravated the damage, evaluated
histologically, irrespective of the pretreatment. Conclusions. Pretreatment-induced COX-2, in addition to COX-1, seemed to be involved in the defense mechanism through minimizing the damage
caused by a subsequent irritant.
Received: October 16, 2000 / Accepted: September 14, 2001 相似文献
72.
Naoto Komada Minako Yamagata Kazutaka Komura Katsuhiro Hayashi Toshihiro Maruyama Hiroaki Kataoka Masashi Koono Hirohito Tsubouchi 《Journal of gastroenterology》1997,32(1):95-101
We report an autopsy case of hepatocellular carcinoma (HCC) with sarcomatous change arising in the context of primary biliary cirrhosis (PBC) in a 79-year-old man. Primary biliary cirrhosis was diagnosed (stage I according to Scheuer's classification) by findings on blood biochemical analysis, laparoscopy, and liver biopsy at age 69 years. Five years later, (at age 74 years), a mass lesion was detected in the S6 region of the liver by abdominal ultrasonography, and target biopsy revealed well differentiated HCC. Blood biochemistry, ultrasonography, and computed tomography findings showed that the PBC had progressed to stage IV (cirrhotic stage). Percutaneous ethanol injection therapy (PEIT) was administered to the HCC several times over a 5-year period; however, the patient died of liver failure in February, 1994 (at age 79 years). Viral markers for hepatitis B and C were negative during the course, and hepatitis C virus RNA was not detected by polymerase chain reaction. Autopsy findings showed liver cirrhosis and diffuse involvement of spindle-shaped sarcomatoid cells in the liver, particularly in the S6 region, associated with several nodules of trabecular HCC cells. A zone of transition between the sarcomatoid cells and the trabecular hepatocellular carcinoma cells was observed. The sarcomatoid cells were diffusely disseminated in the peritoneal cavity and had metastasized to multiple organs. Immunohistochemically, the cells were positive for fibrinogen, as were the coexisting trabecular hepatocellular carcinoma cells. The HCC had been treated several times with PEIT. Of interest, PEIT may be an important factor in this type of tumor progression. 相似文献
73.
We examined the effects of cyclic adenosine 3',5'-monophosphate (cAMP) and protein kinase A (PKA) on the ligand-dependent transactivation mediated via the 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) receptor (VDR). A human VDR expression plasmid was transfected into HeLa, Saos-2 and MG63 cells with a luciferase reporter gene construct containing the vitamin D responsive element. With the addition of 0.5 mM 8 bromo-cAMP, the response to 1,25(OH)2D3 was suppressed to 61 and 78% in the HeLa and Saos-2 cells, respectively. The suppressive effect of 8 bromo-cAMP was observed without the introduction of the VDR expression plasmid in the MG63 cells. In the HeLa cells the co-expression of PKA reduced the ligand-inducible transactivation to 61% and the fold induction by 1,25(OH)2D3 to 89% of that without PKA. The CREB binding protein (CBP) was recently reported to integrate the intracellular signals via the cAMP/PKA cascade and nuclear hormone receptors. However, the suppressive effect of cAMP was not influenced by the co-expression of CBP. Lastly, we introduced point mutations at possible PKA phosphorylation sites into the VDR expression vector at serine-172 and threonine-175, but both mutant receptors still exhibited reduced transactivation with the co-expression of PKA. These results indicate that the phosphorylation of proteins other than the VDR may also be involved in the inhibitory effect mediated by the cAMP/PKA cascade. 相似文献
74.
The relationship between gallbladder disease and smoking and drinking habits in middle-aged Japanese 总被引:1,自引:0,他引:1
Okamoto M Yamagata Z Takeda Y Yoda Y Kobayashi K Fujino MA 《Journal of gastroenterology》2002,37(6):455-462
Background:
Background: Few studies have investigated the association between smoking and ultrasonographically diagnosed gallbladder (GB) disease,
and their results were uncertain. This study was conducted to examine the association between smoking and drinking and GB
diseases.
Methods: A total of 9947 subjects (age, 30–69 years; 4953 men and 4994 women) voluntarily received a paid medical check-up at our
center in Yamanashi Prefecture in Japan. All of the subjects underwent abdominal ultrasonographic (US) examination, a demographic
check, and a biochemical test, and answered a self-administered questionnaire asking about smoking habits and alcohol consumption.
Of the 9947 subjects, 483 had gallstones, 819 had gallbladder polyps, and 169 were in a state of postcholecystectomy. We compared
the findings in this group with the findings in 8417 people (4144 males and 4273 females) with normal gallbladder.
Results: Multiple regression analysis among males showed that cigarette smoking was inversely related to GB polyps (odds ratio, [OR],
0.76; 95% confidence internal [CI], 0.59–0.98 and OR, 0.74; 95% CI, 0.56–0.98, respectively, for current and ex-smokers).
Ex-smokers a showed positive association with the postcholecystectomy state (OR, 2.56; 95% CI, 1.18–5.52). Light drinkers
showed an inverse relation to GB stones (OR, 0.69; 95% CI, 0.49–0.99), and heavy drinkers showed an inverse relation to GB
polyps (OR, 0.68; 95% CI, 0.51–0.90). Current drinkers showed an inverse relation to the postcholecystectomy state (OR, 0.48;
95% CI, 0.28–0.83).
Conclusions: Cigarette smoking was inversely related to gallbladder polyps in males and was positively related to the postcholecystectomy
state. Drinking was inversely related to gallstones, GB polyps, and the postcholecystectomy state in males.
Received: July 19, 2001 / Accepted: November 2, 2001 相似文献
75.
Higashimoto Y Yamagata Y Taya S Iwata T Okada M Ishiguchi T Sato H Itoh H 《Respirology (Carlton, Vic.)》2008,13(1):128-133
Background and objective: While recent studies have shown that patients with COPD and patients with asthma exhibit evidence of airway and systemic inflammation, markers of systemic inflammation have not been compared between the two diseases.
Methods: To evaluate circulating inflammatory markers, blood was sampled from 111 patients with COPD, 75 control subjects and 46 asthmatic patients (some of whom were smokers). Measurements of WCC, serum levels of fibrinogen, high-sensitivity (hs)-CRP, IL-8, IL-6, tumour necrosis factor-α (TNF-α), transforming growth factor (TGF)-β1, tissue inhibitors of metalloproteinase (TIMP)-1, neutrophil elastase and alpha1-antitrypsin (α1-AT) were performed.
Results: Serum TNF-α, IL-6 and TIMP-1 concentrations were significantly higher in patients with stable COPD and patients with asthma than in control patients. Serum α1-AT levels were significantly higher in COPD patients than in asthmatic patients and control subjects, and serum TGF-β1 levels were higher in asthma patients than in COPD patients. Smoking status had no effect on markers in COPD and asthmatic patients.
Conclusions: Although COPD and asthma share common markers of systemic inflammation, serum levels of TGF-β1 and α1-AT may reflect differences between the diseases. 相似文献
Methods: To evaluate circulating inflammatory markers, blood was sampled from 111 patients with COPD, 75 control subjects and 46 asthmatic patients (some of whom were smokers). Measurements of WCC, serum levels of fibrinogen, high-sensitivity (hs)-CRP, IL-8, IL-6, tumour necrosis factor-α (TNF-α), transforming growth factor (TGF)-β1, tissue inhibitors of metalloproteinase (TIMP)-1, neutrophil elastase and alpha1-antitrypsin (α1-AT) were performed.
Results: Serum TNF-α, IL-6 and TIMP-1 concentrations were significantly higher in patients with stable COPD and patients with asthma than in control patients. Serum α1-AT levels were significantly higher in COPD patients than in asthmatic patients and control subjects, and serum TGF-β1 levels were higher in asthma patients than in COPD patients. Smoking status had no effect on markers in COPD and asthmatic patients.
Conclusions: Although COPD and asthma share common markers of systemic inflammation, serum levels of TGF-β1 and α1-AT may reflect differences between the diseases. 相似文献
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80.
Suguru?Yamashita Kiyoshi?Hasegawa Michiro?Takahashi Junichi?Arita Yoshihiro?Sakamoto Taku?Aoki Yasuhiko?Sugawara Norihiro?KokudoEmail author 《Surgery today》2015,45(4):511-516
Liver resection is recognized as the preferred treatment for patients with colorectal liver metastases (CLM) because it offers long-term survival; it is the only hope for a cure. However, in the majority of cases, liver surgery is contraindicated due to the small volume of the future remnant liver. To extend the surgical indications for CLM, a planned two-stage hepatectomy procedure with portal vein embolization (PVE) was developed specifically for patients with multiple and bilobar CLM. The rationale for performing the procedure was a concern about the possible overgrowth of intrafuture remnant liver lesions following PVE, and it was therefore recommended for all multiple bilobar CLM cases, even when one-stage hepatectomy was technically feasible. We recently performed Hobson’s choice two-stage hepatectomy in two cases for reasons different from those of the original planned two-stage hepatectomy. In the present report, we describe our Hobson’s choice two-stage hepatectomy strategy, which provided favorable short-term outcomes. 相似文献