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71.
We report a rare case of choroidal osteoma masquerading as central serous chorioretinopathy. A 39-year-old man complained of intermittent episodes of blurred vision in the left eye for 2 months. Fundus examination of the left eye showed a dome-shaped elevation at the macular center. Fluorescein angiography showed a patch of pinpoint leakage resulting in a well-defined pool of dye at the macular center. Initial diagnosis was recurrent central serous chorioretinopathy with sequelae in the left eye. Five months later, serous detachment recurred. Computerized tomography and ultrasonography showed a bony plaque at the choroid level, and choroidal osteoma was diagnosed. 相似文献
72.
Insulin treatment is well known to induce progressive body weight gain. However, rapid weight increase due to transient fluid accumulation is rare. Bioelectrical impedance analysis (BIA) is a convenient method for determining body composition and water content. We report an 18-year-old diabetic female with rapid insulin-induced weight gain due to excessive body water retention, found by serial BIA measurement. The patient was admitted to our hospital due to uncontrolled diabetes. She had an initial body weight of 55 kg and height of 165 cm. However, a weight gain of 6.5 kg was noted one week after starting insulin injections and further increased to 8 kg after the second week. Finally a net weight increase of 4 kg from fat and lean mass was attained after two months. The weekly BIA data showed that most of the initial weight gain came from water retention, peaking on day 14 and recovering afterwards. Rapid weight gain shortly after insulin therapy may be due to excessive but reversible water retention, detected by repeated BIA measurements. 相似文献
73.
The ectopic eruption of the teeth into the nasal cavity is a rare phenomenon. We report cases: two involving the nasal cavity and one involving the hard palate and complicated by Aspergillus rhinitis. We describe the clinical and radiologic presentation of these cases and discuss their etiology, complications, diagnosis, and treatment. 相似文献
74.
Protective effects of eugenol against oxidized LDL-induced cytotoxicity and adhesion molecule expression in endothelial cells. 总被引:5,自引:0,他引:5
Hsiu-Chung Ou Fen-Pi Chou Tsung-Min Lin Ching-Hwa Yang Wayne Huey-Herng Sheu 《Food and chemical toxicology》2006,44(9):1485-1495
Eugenol, a natural constituent of a number of aromatic plants and their essential oil fractions, has several biological effects. However, its protective effects against endothelial injury remain unclarified. This study investigates how eugenol affects human umbilical vein endothelial cells (HUVECs) dysfunction mediated by oxidized low density lipoprotein (oxLDL). Our results showed that the suppression of endothelial NO synthase (eNOS) expression, enhancement of adhesion molecules (ICAM, VCAM, and E-selectin) expression, and adherence of monocytic THP1 cells caused by a non-cytotoxic concentration (100 microg/ml) of oxLDL were ameliorated following a eugenol treatment (12.5-100 microM) in HUVECs. Eugneol also inhibited the reactive oxygen species (ROS) generation, intracellular calcium accumulation, and the subsequent mitochondrial membrane potential collapse, cytochrome c release and caspase-3 activation induced by oxLDL. The cytotoxicity and apoptotic features induced by a cytotoxic concentration (200 microg/ml) of oxLDL was also attenuated by eugenol. Our results suggest that eugenol may protect against the oxLDL-induced dysfunction in endothelial cells. 相似文献
75.
Jie Chen Xiao-Xia Yang Min Huang Ze-Ping Hu Ming He Wei Duan Eli Chan Fwu-Shan Sheu Xiao Chen Shu-Feng Zhou 《Drug metabolism and disposition》2006,34(9):1650-1657
RNA interference (RNAi) is a specific and powerful tool used to manipulate gene expression and study gene function. The cytochrome P450 3A4 (CYP3A4) can metabolize more than 50% of drugs. In the present study, we investigated whether vector-expressed small interfering RNAs (siRNAs) altered the CYP3A4 expression and function using the Chinese hamster cell line (V79) overexpressing CYP3A4 (CHL-3A4). Three different siRNA oligonucleotides (3A4I, 3A4II, and 3A4III) were designed and tested for their ability to interfere with CYP3A4 gene expression. Our study demonstrated that transient transfection of CHL-3A4 cells with the 3A4III siRNAs, but not 3A4I and II, significantly reduced CYP3A4 mRNA levels by 65% and protein expression levels by 75%. All these siRNAs did not affect the expression of CYP3A5 at both mRNA and protein levels in V79 cells overexpressing CYP3A5. Transfection of CHL-3A4 cells with 3A4III siRNAs significantly diminished the cytotoxicity of two CYP3A4 substrate drugs, cyclophosphamide and ifosfamide, in CHL-3A4 cells, with the IC50 increased from 55 to 210 microM to >1000 microM. Nifedipine at 5.78, 14.44, and 28.88 microM was significantly (P < 0.01) depleted by approximately 100, 40, and 22%, respectively, in S9 fractions from CHL-3A4 cells compared with parental CHL-pIC19h cells. In addition, transfection of the CHL-3A4 cells with vectors expressing the 3A4III siRNAs almost completely inhibited CYP3A4-mediated nifedipine metabolism. This study demonstrated, for the first time, the specific suppression of CYP3A4 expression and function using vector-based RNAi technique. The use of RNAi is a promising tool for the study of cytochrome P450 family function. 相似文献
76.
PURPOSE: To assess the efficacy of treating submacular hemorrhages secondary to retinal arterial macroaneurysm with intravitreous tissue plasminogen activator (tPA) and gas. PATIENTS AND METHODS: Six consecutive patients (6 eyes) with submacular hemorrhage secondary to retinal arterial macroaneurysm were included in this study. Tissue plasminogen activator, at a dose of 50 microg/0.1 mL, was injected through the pars plana into the vitreous cavity. Gas (0.3-0.5 mL of perfluoropropane) instillation followed tPA injection, either immediately after injection or sometime during the next day. RESULTS: Best postoperative visual acuity improved in 5 of 6 eyes (83%) and was unchanged in 1 of 6 (17%) eyes. In 5 of 6 (83%) eyes, the procedure resulted in complete or partial displacement of submacular hemorrhage out of the foveal area. CONCLUSIONS: Intravitreous injection of tPA and gas, followed by prone positioning of the patient, is an effective and simple treatment of submacular hemorrhage secondary to retinal arterial macroaneurysm. No complication occurred in this series. 相似文献
77.
Su JH Nichol KE Sitch T Sheu P Chubb C Miller BL Tomaselli KJ Kim RC Cotman CW 《Experimental neurology》2000,163(1):9-19
Frontotemporal dementia (FTD) is a neurodegenerative disease which affects mainly the frontal and anterior temporal cortex. It is associated with neuronal loss, gliosis, and microvacuolation of lamina I to III in these brain regions. In previous studies we have described neurons with DNA damage in the absence of tangle formation and suggested this may result in tangle-independent mechanisms of neurodegeneration in the AD brain. In the present study, we sought to examine DNA fragmentation and activated caspase-3 expression in FTD brain where tangle formation is largely absent. The results demonstrate that numerous nuclei were TdT positive in all FTD brains examined. Activated caspase-3 immunoreactivity was detected in both neurons and astrocytes and was elevated in FTD cases as compared to control cases. A subset of activated caspase-3-positive cells were also TdT positive. In addition, the cell bodies of a subset of astrocytes showed enlarged, irregular shapes, and vacuolation and their processes appeared fragmented. These degenerating astrocytes were positive for activated caspase-3 and colocalized with robust TdT-labeled nuclei. These findings suggest that a subset of astrocytes exhibit degeneration and that DNA damage and activated caspase-3 may contribute to neuronal cell death and astrocyte degeneration in the FTD brain. Our results suggest that apoptosis may be a mechanism of neuronal cell death in FTD as well as in AD (228). 相似文献
78.
A patient presented with a huge, pedunculated abdominal cystic lymphangioma arising from the quadrate lobe of the liver near
the round ligament. Microscopically, dilated hepatic ducts with scant liver tissue could be recognized in the main cyst. A
review of the literature reveals no previous report of a lymphangioma arising in this manner or from this area.
Accepted: 31 June 1999 相似文献
79.
Wu LS Sheu SY Huang CC Chiu CH Huang JC Yang JR Lian WX Lai CH Chen YP Lin JH 《The American journal of Chinese medicine》2000,28(3-4):371-377
Our previous report first showed evidence that polysaccharides isolated from ginseng leaves obtained from Jilin, China possess luteotropic activities. In this study, we made further investigations on the root and flowers of Korean ginseng by means of the same bioassay system described briefly as follows. Frozen-thawed bovine luteal cells (1 x 10(5) cells/ml/well) in M199 were incubated in 24-well culture plates at 37 degrees C in a 5 % CO2 incubator. Ten microl of tested drugs with 1, 10 and 100 microg/ml were added into each well. After 4- and 24-hr incubation, the media were harvested and assayed for progesterone by an enzyme immunoassay. The production of progesterone from cells is the indicator for evaluating the action of tested drugs. Results showed that hot water extracts ofginseng flowers (GF-1) with 10 to 100 microg/ml significantly increased progesterone production, whereas those from ginseng root (GR-1) could not. Crude polysaccharides (GF-2) isolated from GF-1 is the active component and the small molecules (mw < 10,000 dalton) are excluded, indicating that the ginseng root has no luteotropic activities, but the polysaccharides of ginseng flowers have. 相似文献
80.
Two new chromenes, ficuformodiol A and ficuformodiol B, and nine known compounds including one chromene, spatheliachromen, six flavonoids, obovatin, carpachromene ( 5), apigenin ( 6), norartocarpetin ( 7), steppogenin, 6-prenylpinocembrin, one benzopyran, chromenylacrylic acid, and one isocoumarin, ( R)-(-)-mellein, were obtained from the cytotoxic chloroform-soluble fraction of the stems of Ficus formosana f. formosana (Moraceae). Their structures were determined by means of spectroscopic analyses. Compounds 5, 6 and 7 exhibited significant cytotoxicity against HepG2, PLC/PRF/5 and Raji cancer cell lines in vitro. 相似文献