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991.
Costunolide is an active compound isolated from the root of Saussurea lappa Clarks, a Chinese medicinal herb, and is considered a therapeutic candidate for various types of cancers. Nevertheless, the pharmacological pathways of costunolide are still unknown. In this study, we investigate the effects of costunolide on the induction of apoptosis in HL-60 human leukemia cells and its putative pathways of action. Using apoptosis analysis, measurement of reactive oxygen species (ROS), and assessment of mitochondrial membrane potentials, we show that costunolide is a potent inducer of apoptosis, and facilitates its activity via ROS generation, thereby inducing mitochondrial permeability transition (MPT) and cytochrome c release to the cytosol. ROS production, mitochondrial alteration, and subsequent apoptotic cell death in costunolide-treated cells were blocked by the antioxidant N-acetylcystein (NAC). Cyclosporin A, a permeability transition inhibitor, also inhibited mitochondrial permeability transition and apoptosis. Our data indicate that costunolide induces the ROS-mediated mitochondrial permeability transition and resultant cytochrome c release. This is the first report on the mechanism of the anticancer effect of costunolide.  相似文献   
992.
Die-Huang-Wan is a herbal mixture widely used in Chinese traditional medicine to treat diabetic disorders. We have investigated the effect of Die-Huang-Wan on plasma glucose concentration in-vivo. Die-Huang-Wan was administered orally (5.0, 15.0 or 26.0 mg kg(-1)) to three rat models. Wistar rats were used as the normal animal model, rats with insulin-resistance (induced by the repeated thrice daily injection of human long-acting insulin) were used as the non-insulin-dependent diabetic model, and streptozotocin-induced diabetic rats were used as the insulin-dependent diabetic model. In normal rats, approximately 1 h after oral administration of Die-Huang-Wan the plasma glucose concentration decreased significantly in a dose-dependent manner, from 5 to 26.0 mg kg(-1). A similar effect was observed in rats with insulin-resistance. However, this effect was not observed in streptozotocin-induced diabetic rats, even at an oral dose of 26.0 mg kg(-1). These results suggested an insulin-dependent action, a view supported by the increase of plasma insulin-like immunoreactivity in normal rats receiving Die-Huang-Wan. The results indicated that Die-Huang-Wan had an ability to stimulate the secretion of insulin and this preparation seemed helpful in improving the diabetic condition, especially hyperglycaemia in type-II diabetes.  相似文献   
993.
Lin HL  Liu TY  Wu CW  Chi CW 《Cancer》2001,92(3):500-509
BACKGROUND: 2-Methoxyestradiol (2-Me), one of the estrogen metabolites, has recently been found to possess anti-angiogenesis activity in vivo. Many chemotherapeutic agents, such as taxol, docetaxel, and vinblastine, interact with microtubules and then induce apoptosis. It has been suggested that 2-Me acts on microtubules and results in G(2)/M-cycle arrest of tumor cells. Whether 2-Me induces apoptosis in gastric carcinoma cell lines is not known. Moreover, reactive oxygen species (ROS) produced by 2-Me may be involved in cytotoxicity of tumor cells. Thus, another objective of this study was to evaluate the relation between cell cycle arrest, ROS formation, and caspase activity levels after 2-Me treatment in gastric carcinoma cells. METHODS: It was determined whether 2-Me directly induced apoptosis in two gastric carcinoma cell lines (SC-M1 and NUGC-3) through caspase-3 and caspase-8 activation and, eventually, induced DNA fragmentation. To clarify the effect of 2-Me-induced G(2)/M arrest in apoptosis, calcium ionophore, A23187, and thapsigargin were used to modulate 2-Me-induced cell cycle responses. Moreover, the role of 2-Me-induced ROS formation in the cell cycle responses also was evaluated. RESULTS: It was found that 2-Me treatment resulted in G(2)/M-cycle arrest, caspase-8 and caspase-3 activation, and DNA fragmentation. In addition, the 2-Me induced, concomitant increases of peroxide and superoxide anions were correlated with G(2)/M-cycle arrest. Treatment with calcium ionophore A23187 and thapsigargin partially reversed the 2-Me-induced G(2)/M-cycle arrest, with a concomitant decrease in both peroxide and superoxide levels. Moreover, A23187 blocked the 2-Me-induced caspase-3 activation, whereas thapsigargin had no effect. Treatment with calcium channel blockers did not affect 2-Me-induced cell cycle arrest or caspase-3 activation. CONCLUSIONS: These results suggest that the 2-Me-induced apoptosis of gastric carcinoma cells by DNA fragmentation accompanied caspase activation. Elevation of free radicals was associated with G(2)/M-cycle arrest. The induction of G(2)/M-cycle arrest is not a prerequisite for caspase activation.  相似文献   
994.
Frequent epigenetic inactivation of RASSF1A in human bladder carcinoma   总被引:16,自引:0,他引:16  
Lee MG  Kim HY  Byun DS  Lee SJ  Lee CH  Kim JI  Chang SG  Chi SG 《Cancer research》2001,61(18):6688-6692
  相似文献   
995.
Tibiocalcaneal fusion using intramedullary rods for severe end-stage Charcot deformity is challenging. Complications such as nonunion, delayed union, recurrent deformity, wound problems, and infection are common. Revision cases present the additional obstacle of obtaining bony purchase in the calcaneal screws. We present a technique using readily available instrumentation to obtain reliable calcaneal fixation.  相似文献   
996.
Primary malignant melanoma of the oesophagus (PMME) is a rare tumour. It has characteristic pathological and immunohistochemical features and diagnosis and management is difficult. This paper reports a patient with PMME, with a review of literature. The literature search was made with the Index Medicus/MEDLINE database using ‘melanoma’ and ‘oesophagus’ as key words, and cross‐referencing of other articles on the subject. Three‐phase oesophagectomy was performed and the patient died 2 months afterwards with respiratory failure and bone metastasis. Primary malignant melanoma of the oesophagus is a highly lethal tumour. Radical surgery is the treatment of choice.   相似文献   
997.
PURPOSE: The aim of this study was to determine the ability of preoperative serum CA-125 to predict optimal primary tumor cytoreduction in patients with Stage III epithelial ovarian carcinoma. METHODS: We performed a retrospective chart review of 100 consecutive patients with Stage III ovarian carcinoma who had a serum CA-125 drawn prior to primary cytoreductive surgery. We used a receiver operating characteristic curve to determine the CA-125 level with the maximal prognostic power in predicting optimal versus suboptimal cytoreduction. RESULTS: The median CA-125 level for the 100 patients was 819 U/ml (range 5.6-26,200 U/ml). Optimal cytoreduction (diameter of largest residual tumor nodule < or =1 cm) was obtained in 45 cases (45%). The probability of performing optimal cytoreduction decreased with increasing CA-125 levels. A preoperative CA-125 level of 500 U/ml was identified as the value with the most predictive power. Optimal cytoreduction was achieved in 33 of the 45 cases (73%) with a CA-125 less than 500 U/ml compared to only 12 of the 55 cases (22%) with a CA-125 greater than 500 U/ml. Using a threshold level of 500 U/ml, the preoperative serum CA-125 level was able to predict optimal versus suboptimal cytoreduction with a sensitivity of 78%, specificity of 73%, positive predictive value of 78%, and negative predictive value of 73%. CONCLUSION: The probability of performing optimal cytoreduction in patients with Stage III ovarian carcinoma and a preoperative CA-125 greater than 500 U/ml was approximately one in five. These patients may be candidates for initial laparoscopic evaluation to obtain a confirmatory tissue diagnosis and to determine resectability.  相似文献   
998.
We studied the cognitive effects of antiepileptic drugs (AED), by investigating epileptic children who were seizure-free for at least 2 years and who had undergone fixed monotherapy. Seventy consecutive epileptic children (25 with carbamazepine (CBZ), 22 with phenobarbital (PB), and 23 with valproate (VPA)) were examined by Wechsler Intelligence Scale for Children-Revised (WISC-R) and auditory event-related potentials (P(300)) at three sessions: before AED reduction, then 1 and 7 months after complete withdrawal of treatment. There were no significant differences in IQ and subtests scores of WISC-R in any group at any of the three sessions. P(300) latencies were significantly increased in the children receiving PB but not in children receiving CBZ or VPA. P(300) amplitudes were increased but not significantly different among the three groups. These findings suggest that PB may affect cognitive function on children, but the changes of P(300) latencies may improve after discontinuation.  相似文献   
999.
We present a case of cerebellopontine (CP) angle ganglioglioma in a young child with developmental delay and no trigeminal nerve symptoms. MR imaging demonstrated a mass of homogeneous low signal intensity in the left CP angle on T1-weighted images with no enhancement with gadolinium, and of relatively homogeneous high signal intensity on T2-weighted images.  相似文献   
1000.
The triple-phase CT image appearance of post-irradiated livers   总被引:12,自引:0,他引:12  
Objective: To evaluate the sequential CT appearance of the liver after hepatic irradiation and to investigate the correlation between CT findings and radiation-induced hepatic injury.Material and Methods: The triple-phase CT images of 18 patients with hepatocellular carcinomas (HCC) after hepatic irradiation were retrospectively reviewed (in total 41 CT studies). The high-dose region within the liver was defined as the area receiving more than 90% of the prescribed irradiation dose. The mean radiation dose was 55.5 Gy. Density changes and patterns of enhancement in the high-dose region were classified as three types: type I, constant low-density change in all phases; type II, low-density change in both pre-contrast and arterial phases, and iso-density change in the portal phase; type III, low- or iso-density change in the pre-contrast phase, low- or high-density change in the arterial phase, and persistent high-density change in the portal phase. The interval between completion of radiotherapy and the CT examinations ranged from 9 to 469 days, with a mean of 147 days.Results: Nine of the 41 CT studies presented with type I, 9 with type II, and 16 with type III CT findings. The mean interval between completion of radiotherapy and the appearance of types I, II, and III CT findings were 74, 183, and 220 days, respectively. The interval was significantly shorter for type I findings than for type II and type III. The difference in interval was not significant between type II and type III. A type I finding with constant low-density change in the high-dose region of the liver was the most common pattern of CT findings within the first 3 months after hepatic irradiation. Either types II or III findings were frequently seen after 3 months.Conclusion: The sequential CT appearance and the density changes may indicate correlation with the pathogenesis of veno-occlusive disease.  相似文献   
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