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91.
The authors experienced a case with obstruction of the inferior vena cava (IVC) and the common bile duct due to a recurrent hepatocellular carcinoma. In order to improve severe edema of the lower extremities and obstructive jaundice, IVC metallic stent as well as biliary stent were applied. A Luminexx stent of 8 cm in length was placed in the bile duct via subcutaneous route after biliary drainage. A spiral zigzag stent of 8 cm in length was also inserted into the IVC through the femoral vein following balloon dilatation of the obstructed portion. Subsequently, jaundice and edema were dramatically improved in a short period of time, which resulted in patient discharge from the hospital. Although the patient died of the cancer in 2 months, the quality of life was well maintained until death.  相似文献   
92.
93.
The guinea-pig basilar artery smooth muscle cell (GBa-SM3) culture system in the Dulbecco's modified Eagle's medium for 3 days serves as a useful in vitro model for assessing antiproliferative effects of various therapeutic agents on vessels. With use of this system we studied whether human serum obtained from patients with acute cerebral infarction (n = 16) would have a proliferative effect on vessels and whether an administration of a free radical scavenger, edaravone, with or without amlodipine would elicit antiproliferative effects. The control serum was obtained from 3 healthy human subjects. Time courses of the cell growth and survival were measured colorimetrically by the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrzolium bromide (MTT) test. The stimulatory effect on the proliferation of GBa-SM3 cells of patients' serum obtained immediately after infarction was significantly (p < 0.05) greater than those obtained from the same patients after the treatment of edaravone for 2 weeks. In addition, the serum obtained from the patients treated by edaravone and amlodipine (n = 7) showed a significantly (p < 0.05) greater antiproliferative effect than that obtained from those treated by edaravone (n = 9). In conclusion, edaravone may have a clinically beneficial antiproliferative effect on vascular smooth muscle cells. Co-administration of amlodipine, possessing an antioxidative calcium channel blocker, with edaravone may be a promising combination to patients with acute cerebral infarction. Further controlled clinical trials with a large number of patients should be warranted.  相似文献   
94.
Proliferation of vascular smooth muscle cells (VSMC) stimulated by oxidative stresses and reactive oxygen species (ROS) may play a pivotal role in the pathogenesis of atherosclerosis. Antiatherosclerotic effects of angiotensin II receptor blockers, angiotensin converting enzyme inhibitors, HMG CoA reductase inhibitors, calcium channel blocker and epalrestat were studied with an in vitro guinea-pig basilar artery smooth muscle cell (GBa-SM3) culture system over 3 days incubated with 0 to 10% of fetal bovine serum. Results demonstrated that simvastatin (0.1 mM), fluvastatin (0.3 mM), amlodipine (0.2 mM) and epalrestat (1 mM) elicited significant (p < 0.05 or 0.01) antiproliferative effects, whereas losartan (1 mM), valsartan (1 mM), enalapril (0.1 mM), captopril (1 mM), trandolapril (0.01 mM), pravastatin (0.7 mM) did not. In conclusion, the present in vitro VSMC culture system may serve as a comprehensive screening method for pleiotropic effects of commonly used therapeutic agents.  相似文献   
95.
RCAS1 (receptor-binding cancer antigen expressed on SiSo cells) inhibits the in vitro growth of receptor-expressing cells and induces apoptosis, which may contribute to the ability of tumor cells to evade host immune surveillance. In this study, we investigated RCAS1 expression in gastric cancer and precancerous lesions by immunohistochemical means. We then analyzed the relationship between RCAS1 expression and clinicopathological variables, and examined whether RCAS1 expression is associated with infiltration of tumor-infiltrating lymphocytes (TILs) and apoptosis of TILs. Of 54 gastric cancers analyzed, RCAS1 expression was positive in 52 (96%) of them. The expression pattern of RCAS1 in gastric cancer cells could be classified as granular staining either enriched in the glandular side of the cytoplasm with polarity (P pattern) or scattered diffusely in the cytoplasm and on the cell membranes (D pattern). Nineteen of 39 intestinal-type carcinomas (49%) showed the P pattern, and all of 13 diffuse type carcinomas (100%) showed the D pattern. In contrast, all RCAS1-positive specimens of gastric adenoma and metaplastic mucosa were of the P pattern. The D pattern of gastric cancers was more frequently recognized in carcinomas with large size (P<0.01), in those with regional lymph node metastasis (P<0.05) and in those that had invaded beyond the submucosa (P<0.01), compared with the P pattern. On the same sections, significantly less TILs were identified in RCAS1-positive areas than RCAS1-negative areas. Furthermore, the rate of apoptosis of TILs was significantly higher in RCAS1-positive areas than in RCAS1-negative areas. The expression and distribution of RCAS1 may be involved in malignant transformation, tumor progression, histological type and tumor escape from host immune surveillance in gastric cancer.  相似文献   
96.
A 10-month-old girl was referred to our hospital because of congenital and persistent bilateral chylothorax and generalized lymphedema as well as long-standing respiratory disturbance. Radiological studies showed a diffuse network of superficial lymphatic vessels without major trunks throughout her entire body as well as the lung. She was diagnosed with systemic lymphangiomatosis complicated with pulmonary lymphangiectasia. Percutaneous puncture in the lower leg was performed to discharge the lymphatic fluid and proved to be effective for the respiratory disturbance. This procedure is safe and easy and effectively improves the quality of life of the patient and the family in case of such a persistent disease.  相似文献   
97.
Resistance to thyroid hormone (RTH) is caused mainly by mutations of the thyroid hormone receptor (TR) beta gene. Although, in vitro, TRalpha1 and TRbeta1 mutants exhibit similar dominant negative effects against wild-type TR, no TRalpha mutants have ever been identified in RTH patients. It has been postulated that mutations in TRalpha gene may be lethal, compensated completely by intact TRbeta or associated with phenotypic manifestations different from RTH. To investigate the consequences of mutant TRalpha1 expression in vivo, we tried to generate two different lines of transgenic mice which express a strong or a weak dominant negative mutant TR alpha1, respectively. First, we expressed betaF451X identified in a patient with severe RTH and alphaF397X, which has an identical C-terminal truncation and a similarly strong dominant negative potency to betaF451X, under the control of human polypeptide chain elongation factor 1alpha promoter. Six betaF451X-transgenic mice were born from 223 transferred embryos, giving a transgenic frequency of 2.7%. By contrast, expression of alphaF397X resulted in quite a low transgenic frequency with 0.39% of the transferred embryos bearing the transgene. Only three transgenic mice were born with no apparently overt abnormalities, of which one male produced F1 offspring. The transgenic progeny expressed alphaF397X in the testis but we did not succeed in generating transgenic mice expressing alphaF397X in multiple organs. To avoid toxic effects mediated by a strong dominant negative activity of mutant TRalpha1, we exchanged alphaF397X for alphaK389E, which has an identical missense mutation and a relatively weak transdominant potency as betaK443E identified in a patient with mild RTH. When expressed by cytomegalovirus immediate early enhancer-chicken beta-actin promoter, we did not succeed in creating alphaK389E-transgenic mice despite three independent transgene-injections. These findings define crucial in vivo functions of mutant TRalpha1s during mouse fetal development and suggest the possibility that the expression of a dominant negative mutant TRalpha1 in extensive tissues from the early embryonal stages might be lethal.  相似文献   
98.
99.
Proliferation of vascular smooth muscle cells stimulated by reactive oxygen species (ROS) may play a pivotal role in the pathogenesis of atherosclerosis. To clarify mechanisms by which ROS promote vascular atherogenesis, effects of fluvastatin, amlodipine, ozagrel (thromboxane synthetase inhibitor), GF109203X (a protein kinase C inhibitor) and Y27632 (a ROCK inhibitor) on the proliferation of guinea-pig basilar artery smooth muscle cells (GBa-SM3) in a 5% FBS culture medium were studied over 3 d in the presence or absence of a free radical scavenger, edaravone. Viability of cells at the end of incubation was measured by the 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) test. Results demonstrated that fluvastatin and amlodipine by themselves possess antiproliferative effects on the GBa-SM3 cells at 10-100 microM and 0.1-1 microM, respectively. While edaravone possessed no antiproliferative effect by itself at 100 microM, it significantly (p<0.05) augmented the antiproliferative effects of fluvastatin and amlodipine. In addition, ozagrel, GF109203X and Y27632 possessed no appreciable effects on the cell growth by themselves. However, coincubation of edaravone at 100 microM with these agents elicited significant antiproliferative effects for ozagrel, GF109203X and Y27632 at 10-100 microM, 1-10 microM and 0.1-1 microM, respectively. In conclusion, edaravone may have clinically beneficial interactions with fluvastatin, amlodipine and ozagrel regarding the prevention of vascular atherosclerosis. The interactions between edaravone and the inhibitors of protein kinase C and ROCK were suggestive of possible contributions of ROS-triggered intracellular signals associated with these enzymes to vascular atherogenesis, but further studies are required for confirmation.  相似文献   
100.
Two technical challenges must be overcome before brain fiber tracking with diffusion-tensor magnetic resonance (MR) imaging can be applied to clinical practice: Imaging time must be shortened, and image distortion must be minimized. Single-shot echo-planar MR imaging with parallel imaging technique enabled both objectives to be accomplished. Twenty-three consecutive patients with brain tumors underwent MR imaging with a 1.5-T whole-body MR system. Fiber tracts on the lesion side in the brain had varying degrees of displacement or disruption as a result of the tumor. Tract disruption resulted from direct tumor involvement, compression on the tract, and vasogenic edema surrounding the tumor. This diffusion-tensor MR imaging method with the parallel imaging technique allows clinically feasible brain fiber tracking.  相似文献   
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