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1.
OBJECTIVE: Vacuolar H(+)-adenosine triphosphatase plays a pivotal role in pH regulation and molecular transport across the vacuolar membranes and is involved in cell proliferation and transformation. In the present study, possible involvement of vacuolar H(+)-adenosine triphosphatase in neointimal formation was investigated in an organ culture model of human saphenous vein. Methods and results: Cultured saphenous vein segments developed neointimal formation and marked thickening of the media within 14 days. Neointimal formation and medial thickening were completely inhibited by 10 nmol/L bafilomycin A(1), a selective inhibitor of vacuolar H(+)-adenosine triphosphatase, although structurally related macrolide antibiotics FK-506 and erythromycin were without an effect. The neointimal cells were positive for alpha-smooth muscle actin and vimentin but negative for desmin, indicative of myofibroblasts. The emergence of myofibroblasts was inhibited, and endothelial cells were preserved in the saphenous vein segments treated with bafilomycin A(1). Uptake of bromodeoxyuridine, a proliferation marker, by myofibroblasts was abrogated in the saphenous vein segments treated with 10 nmol/L bafilomycin A(1). Detection of apoptotic cells by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling concomitant with identification of desmin-expressing smooth muscle cells demonstrated that neointimal myofibroblasts, but not medial smooth muscle cells, that expressed desmin underwent apoptosis by treatment with bafilomycin A(1). CONCLUSIONS: These results suggest that vacuolar H(+)-adenosine triphosphatase may be involved in myofibroblast growth that contributes to neointimal formation and medial thickening in cultured human saphenous vein. Increased sensitivity of myofibroblasts, but not endothelial cells, and differentiated smooth muscle cells to bafilomycin A(1) may have potential therapeutic implications in the treatment for vein graft disease.  相似文献   
2.
Six new triterpene saponins, 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-xylopyranosyl-(1-->2)-beta-D-glucuronopyranosyl-21-epi-kudzusapogenol A (1), 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranosyl-(1-->2)-beta-D-glucuronopyranosyl-21-epi-kudzusapogenol A (2), 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-xylopyranosyl-(1-->2)-beta-D-glucuronopyranosyl-22-O-beta-D-glucopyranosyl-21-epi-kudzusapogenol A (3), 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranosyl-(1-->2)-beta-D-glucuronopyranosyl-22-O-beta-D-glucopyranosyl-21-epi-kudzusapogenol A (4), 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-xylopyranosyl-(1-->2)-beta-D-glucuronopyranosyl-22-O-alpha-L-arabinopyranosyl-21-epi-kudzusapogenol A (5), and 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranosyl-(1-->2)-beta-D-glucuronopyranosyl-22-O-alpha-L-arabinopyranosyl-21-epi-kudzusapogenol A (6), were isolated from the roots of Astragalus flavescens, together with the known trajanoside B, azukisaponin V, and astragalosides IV, VII, and VIII. Their structures were established mainly by 2D NMR techniques and mass spectrometry.  相似文献   
3.
Interventional radiologic treatment for idiopathic portal hypertension   总被引:8,自引:0,他引:8  
Purpose: To evaluate the usefulness of interventional radiological treatment for idiopathic portal hypertension. Methods: Between 1995 and 1998, we performed an interventional radiological treatment in five patients with idiopathic portal hypertension, four of whom had refused surgery and one of whom had undergone surgery. Three patients with gastroesophageal varices (GEV) were treated by partial splenic embolization (PSE), one patient with esophageal varices (EV) and massive ascites by transjugular intrahepatic portosytemic shunt (TIPS) and PSE, and one patient with GEV by percutaneous transhepatic obliteration (PTO). Midterm results were analyzed in terms of the effect on esophageal and/or gastric varices. Results: In one woman with severe GEV who underwent three sessions of PSE, there was endoscopic confirmation that the GEV had disappeared. In one man his EV shrunk markedly after two sessions of PSE. In two patients slight reduction of the EV was obtained with one application of PSE combined with endoscopic variceal ligation therapy. PTO for GV in one patient resulted in good control of the varices. All patients have survived for 16–42 months since the first interventional treatment, and varices are well controlled. Conclusion: Interventional radiological treatment is effective for patients with idiopathic portal hypertension, whether or not they have undergone surgery.  相似文献   
4.
STUDY OBJECTIVE: To evaluate the safety and efficacy of small-bore, silastic drains for patients undergoing general thoracic surgery. PATIENTS AND METHODS: Twenty-five patients who received soft, small-bore, silastic drains were compared with 17 patients who received semi-rigid double lumen (DL) tubes retrospectively. RESULTS: The pain score was significantly lower in patients who received the silastic tubes in video-assisted thoracoscopic surgery (VATS) cases on postoperative days 5 and 6 , after continuous epidural analgesia had finished (P=0.018). No specific morbidity was seen in the patients who received silastic tubes. CONCLUSION: We considered that soft, small-bore silastic drains were just as effective as traditional DL tubes, but caused less pain especially in VATS cases.  相似文献   
5.
6.
A 24-year-old man presented with chest pain. He was diagnosed as having a type A acute aortic dissection and an annulo-aortic aneurysm. After emergency surgery for an aortic root replacement, his electrocardiogram showed ST-segment depression and T-wave inversion. Echocardiography showed asynergy of the left ventricle without coronary ostial pathology. Heart catheterization revealed no coronary stenosis, but the true lumen of the residual ascending aorta had extreme diastolic narrowing due to flap suffocation. This resulted in coronary malperfusion. The pullback pressure curve confirmed the mechanism. The patient underwent a surgical re-intervention for a total arch repair, which diminished the coronary malperfusion. At a follow-up appointment four years and four months later, the patient was doing well.  相似文献   
7.
Mucocele-like tumors (MLTs) of the breast are rare, with only 11 cases reported from Japan and 35 cases from other countries. MLTs of the breast were first described by Rosen in 1986. They are believed to be related to atypical ductal hyperplasia, ductal carcinoma, or mucinous carcinoma. It is difficult to diagnose this tumor preoperatively, and especially difficult to differentiate between benign and malignant forms. We report a case of MLT associated with ductal carcinoma in situ, which was initially diagnosed as fibroadenoma by mammography and ultrasonography, and as mucinous carcinoma by fine-needle aspiration cytology. We discuss the characteristic findings of imaging and the appropriate clinical treatment of this tumor. The characteristic image first signals the possibility of this tumor, following which the diagnosis can be confirmed by pathological examination of a fully excised tumor specimen. Breast-conserving surgery is recommended because of the low risk of high-grade malignancy, even when malignancy is confirmed, and lymph node dissection may be avoided.  相似文献   
8.
The effects of certain disinfectants on the stability of a polymethyl methacrylate denture base resin were investigated, including those of a novel disinfection method using reactive oxygen species (ROS). The surface roughness and flexural strength were analyzed to assess the effects of the disinfectants on material properties. The following disinfectants were tested: 5% sodium hypochlorite, 70% alcohol, and ROS. Furthermore, the attachment of Candida albicans to the resin surface was investigated. The disinfection method using sodium hypochlorite significantly increased the surface roughness and decreased flexural strength. The surface roughness and flexural strength of the ROS-treated specimens did not significantly differ from those of the control specimens, and the ROS-treated specimens exhibited diminished Candida attachment. These results demonstrate that the ROS disinfection method preserves acceptable material stability levels in polymethyl methacrylate resins.  相似文献   
9.
10.
The efficient induction of cardiomyocyte differentiation from embryonic stem (ES) cells is crucial for cardiac regenerative medicine. Although Wnts play important roles in cardiac development, complex questions remain as to when, how and what types of Wnts are involved in cardiogenesis. We found that Wnt2 was strongly up-regulated during cardiomyocyte differentiation from ES cells. Therefore, we investigated when and how Wnt2 acts in cardiogenesis during ES cell differentiation. Wnt2 was strongly expressed in the early developing murine heart. We applied this embryonic Wnt2 expression pattern to ES cell differentiation, to elucidate Wnt2 function in cardiomyocyte differentiation. Wnt2 knockdown revealed that intrinsic Wnt2 was essential for efficient cardiomyocyte differentiation from ES cells. Moreover, exogenous Wnt2 increased cardiomyocyte differentiation from ES cells. Interestingly, the effects on cardiogenesis of intrinsic Wnt2 knockdown and exogenous Wnt2 addition were temporally restricted. During cardiomyocyte differentiation from ES cells, Wnt2 didn't activate canonical Wnt pathway but utilizes JNK/AP-1 pathway which is required for cardiomyocyte differentiation from ES cells. Therefore we conclude that Wnt2 plays strong positive stage-specific role in cardiogenesis through non-canonical Wnt pathway in murine ES cells.  相似文献   
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