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41.
N-3 polyunsaturated fatty acids such as docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) have protective effects against atherosclerosis. Monocyte chemotactic protein (MCP)-1 is a major inflammatory mediator in the progression of atherosclerosis. However, little is known about the regulation of Mcp-1 by DHA and EPA in vessels and vascular smooth muscle cells (VSMCs). In this study, we compared the effect of DHA and EPA on the expression of Mcp-1 in rat arterial strips and rat VSMCs. DHA, but not EPA, suppressed Mcp-1 expression in arterial strips. Furthermore, DHA generated 4-hydroxy hexenal (4-HHE), an end product of n-3 polyunsaturated fatty acids (PUFAs), in arterial strips as measured by liquid chromatography-tandem mass spectrometry. In addition, 4-HHE treatment suppressed Mcp-1 expression in arterial strips, suggesting 4-HHE derived from DHA may be involved in the mechanism of this phenomenon. In contrast, Mcp-1 expression was stimulated by DHA, EPA and 4-HHE through p38 kinase and the Keap1-Nuclear factor erythroid-derived 2-like 2 (Nrf2) pathway in VSMCs. In conclusion, there is a dual effect of n-3 PUFAs on the regulation of Mcp-1 expression. Further study is necessary to elucidate the pathological role of this phenomenon.  相似文献   
42.
An 83-years-old woman diagnosed with advanced Epidermal growth factor receptor (EGFR)-mutant lung adenocarcinoma was administered afatinib as a first-line treatment. On Day 17, the patient presented with grade 3 diarrhea and a blood test analysis showed an increased inflammatory response. Afatinib treatment was discontinued on the same day. On Day 26, the patient displayed blepharedema and multiple irregular erythema covering her entire body. Drug-induced hypersensitivity syndrome (DIHS) was suspected, and the systemic administration of 30 mg/day prednisolone was administered. The symptoms subsided thereafter. A blood test analysis 3 weeks after onset revealed a reactivation of Human herpesvirus 6 (HHV-6) and a diagnosis of DIHS due to afatinib therapy was confirmed.  相似文献   
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An 84-year-old man was admitted with epigastralgia. Computed tomography showed contrast-enhanced wall thickness in the cystic duct. An endoscopic examination revealed short irregular stricture in the cystic duct, and per-oral cholangioscopy revealed a reddish papillary tumor at the stricture site. Surgical resection revealed high-grade biliary intraepithelial neoplasia (BilIN) at the stricture site of the cystic duct. To our knowledge, this is the first case of a solitary high-grade BilIN epithelium in the cystic duct detected by per-oral cholangioscopy.  相似文献   
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Hepatic venous outflow obstruction is a relatively uncommon but important and devastating complication occurring after liver transplantation. Recently, right lateral sector liver grafts have sometimes been used in living-donor liver transplantation (LDLT), but, to our knowledge, early hepatic venous outflow obstruction has never been reported in right lateral sector LDLT. A 58-year-old woman was diagnosed with liver cirrhosis and hepatocellular carcinoma and underwent right lateral sector LDLT. Postoperatively, she developed liver dysfunction. Doppler ultrasound examination revealed flat waveforms and low-flow velocity in the right hepatic vein (RHV). A computed tomography (CT) scan revealed a ventrally distorted RHV due to hypertrophy of the liver graft. Hepatic venous obstruction was suspected and a hepatic venogram was performed. The venogram revealed stenosis of the RHV due to the distortion of the vein. We performed percutaneous transfemoral balloon dilatation, but this was not effective. We then inserted an expandable metallic stent (EMS) into the RHV. After the EMS placement, the condition of the patient improved. Venogram and CT data suggested that the obstruction of the RHV developed because of distortion of the RHV to the ventral side during liver regeneration.  相似文献   
46.
Osteoprotegerin (OPG) is a soluble receptor expressed in the serum of patients with diabetes, arthritis and pancreatic cancer. While OPG has been considered a tumor survival factor for bone metastasizing breast and prostate cancers, the role of OPG in pancreatic cancer, which itself rarely metastasizes to bone, is not known. Pancreatic ductal adenocarcinoma (PDAC) cell lines were found to secrete OPG and the level of OPG production correlated with sensitivity to TRAIL-induced apoptosis. Silencing OPG sensitized cells to TRAIL-induced apoptosis. Interestingly, a positive correlation was noted between OPG production level and K-Ras mutation status. Earlier studies implicated K-Ras in conferring resistance to TRAIL-induced apoptosis in pancreatic cells and this study demonstrates that K-Ras mediated TRAIL resistance in pancreatic cancer cells occurs due to increased OPG production. Silencing K-Ras in pancreatic cancer cells decreased OPG levels and increased sensitivity to TRAIL-induced apoptosis. These observations indicate that OPG can play a role in both cell survival and in PDAC cell sensitivity to TRAIL-induced apoptosis, which may contribute to metastasis. Targeted inhibition of OPG binding to TRAIL may represent a therapeutic approach in the treatment of pancreatic cancer.  相似文献   
47.
Sessile serrated adenoma/polyps (SSA/Ps) of the colon are thought to be precursors of sporadic carcinomas. Although it is suggested that SSA/P may grow rapidly from the early stage, its cell kinetics remains obscure. To solve this problem, we analyzed the mitotic and apoptotic activity of normal crypts, microvesicular hyperplastic polyps (MVHPs), and tubular adenomas (TAs), using phospho-histone H3 and cleaved caspase 3 immunohistochemistry. The mitotic index for SSA/Ps (mean, 5.63) and TAs (6.98) was significantly higher than those for normal crypts (2.72) and MVHPs (2.86). Of all tested lesions, the apoptotic index was lowest for SSA/Ps (0.96; normal, 2.71; MVHPs, 2.62; TAs, 6.01) with statistically significant differences. The net growth ratio was close to 1.0 in normal crypts (1.07) while remaining low in MVHPs (1.06) and TAs (1.38), but was markedly elevated in SSA/Ps (7.32, P?<?0.01) due to the large imbalance between mitosis and apoptosis. As to apoptosis regulatory proteins, expression of anti-apoptotic Bcl-2 was significantly reduced or undetectable in MVHPs and SSA/Ps, while TAs showed stronger staining than normal crypts. Expression of pro-apoptotic Bax and its activators, Bim and Bad, was significantly reduced in MVHPs and SSA/Ps. We suggest that other complex mechanisms may act synergistically with Bax, Bim, or Bad deficiency to regulate apoptosis suppression in SSA/Ps.  相似文献   
48.
Well‐differentiated papillary mesothelioma (WDPM) is a distinct subtype of mesothelial tumor from diffuse malignant mesothelioma (DMM), with an uncertain malignant potential. The relationship between WDPM and DMM, with regard to the ability of the former to develop into the latter, is also unknown. A 58‐year‐old woman, diagnosed with a rectal carcinoid tumor, underwent removal of the lymph nodes via the abdomen in 2004. A large number of white miliary nodules were identified on the mesentery and peritoneum, which were histologically diagnosed as WDPM. No further therapy was administered, but the patient was followed‐up using imaging methods. Seven years later, an abdominal wall mass was discovered using positron emission tomography‐computed tomography, and a laparotomy biopsy was performed. DMM was diagnosed, because mesothelioma with extended invasion had been histologically identified. Mesothelioma similar to papillary proliferation was present on the outer layer of the peritoneum, and an infiltrating lesion with continuous restiform or solid‐like structures was noted. WDPM was believed to have undergone malignant transformation. Compared to DMM, WDPM has a good prognosis and is considered a benign or borderline neoplasm. Our findings suggest that WDPM does have malignant potential, however, because histological findings indicated a malignant transformation of WDPM to DMM.  相似文献   
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