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61.

Background

Glucocorticoids inhibit hepatocellular proliferation and modulate the expression of oncogenes and tumor suppressor genes via mechanisms involving the glucocorticoid receptor. Glucocorticoids also produce a receptor-mediated inhibitory effect on both basal and hormone-stimulated expression of a newly discovered family of molecules important for shutting off cytokine action. We therefore hypothesized that inhibiting glucocorticoid receptors may disturb hepatocellular growth and apoptosis. Consequently, we investigated the effect of RU486, a potent antagonist of the glucocorticoid receptor, on basal levels of hepatocellular proliferation and apoptosis in male B6C3F1 mice. Furthermore, we evaluated the effect of this compound on cellular genes involved in the regulation of these important processes.

Results

Data show that treatment of male B6F3C1 mice with RU486 (2 mg/kg/d, ip) for 7 days dramatically inhibited liver cell proliferation by about 45% and programmed hepatocellular death by approximately 66%. RU 486 also significantly increased hepatic expression of the oncogenes mdm2 and JunB, while reducing that of the tumor suppressor gene p53.

Conclusion

Exposure to RU486 may ultimately enhance the susceptibility of the liver to cancer risk by diminishing its ability to purge itself of pre-cancerous cells via apoptosis. This effect may be mediated through increases in the hepatic expression of the oncogene mdm2, coupled with decreases in that of the tumor suppressor gene p53. The decrease in hepatocellular proliferation caused by RU 486 may be related to effects other than its anti-glucocorticoid activity.
  相似文献   
62.
A case is presented of an 18-year-old athlete with fibrous dysplasia of the femoral neck and head. The approach was by joint plastic and orthopaedic teams, which minimized operating time and allowed the option of vascular bone grafting. The lesion was curetted through a greater trochanteric window and the defect reconstructed with a free vascularized fibula graft with excellent result. Weight bearing was achieved in six months and there was minimal donor site morbidity. We believe the free vascularized fibula graft to be a reconstructive option, in difficult orthopaedic problems, facilitated by microsurgery and there is immense benefit of a joint effort between the orthopaedic and plastic surgical teams.  相似文献   
63.
Isolated congenital sick sinusal syndrome on non harmed heart is a rare affection. Its association with an atrio-ventricular block is exceptional. The authors report a case of a 19 year-old patient, with an early history of bradycardia, hospitalised for effort intolerance. His electrocardiogram reveals a high degree sino-atrial block replaced by a junctional rhythm at 30/mn. During Treadmill test, the sinusal acceleration is satisfactory and an effort atrio-ventricular block was present. He later had a definitive stimulation under DDDR. This report shows that the sinusal node, in the same way as the atrio-ventricular node may be injured by congenital dysimmunitary process. The coexistence of these two conductive troubles worsen the prognosis and should lead more often to the practice of definitive stimulation by the only mode DDDR.  相似文献   
64.
65.
A 54-year-old woman with a history of fatigue and shortness of breath was found to have a pericardial effusion and mild mediastinal lymphadenopathy. Video-assisted pericardioscopy revealed thickened pericardium studded with multiple nodules. Histologically the tumor was diagnosed as papillary adenocarcinoma. The site of the primary tumor could not be identified. As lung cancer is one of the most frequent causes of pericardial metastases the patient was treated with cisplatin and vinblastin. Following 5 courses of chemotherapy--given over a 4 month period--the amount of pericardial effusion and pericardial thickness did not change. The material from pericardial biopsy was reexamined and positive immunostaining for calretinine was found. The final diagnosis was primary pericardial mesothelioma of epithelioid type. Palliative radiotherapy of mediastinum was planned but the patient deteriorated and died due to disease progression with venous thrombosis and superior vena cava syndrome. The case illustrates the difficulties in establishing diagnosis of primary pericardial mesothelioma which is a rare tumor with poor prognosis.  相似文献   
66.
Prognostic significance of p53 and FHIT in advanced oropharyngeal carcinoma   总被引:1,自引:0,他引:1  
OBJECTIVE: To determine the prognostic significance of p53 and fragile histidine triad (FHIT) expression in advanced oropharyngeal squamous cell carcinoma. STUDY DESIGN: A retrospective collection of clinical data was correlated with the protein expression. METHOD: The expression of p53 and FHIT in specimens from patients with previously untreated advanced squamous cell carcinoma of the oropharynx was determined by immunohistochemistry. The expression of p53 and FHIT was statistically correlated with survival outcome. The primary endpoints were overall survival and disease-free survival. RESULTS: Thirty-four patients were analyzed in this study. Overexpression of p53 was observed in 41.2% (14/34) of tumors and was associated with a trend toward an improved overall survival using univariate (P =.1088, risk ratio [RR] = 0.503) and multivariate (P =.1533, RR = 0.470) analyses. Marked reduction or complete absence of FHIT expression was observed in 57.6% (19/33) of tumors. Patients with tumors showing no reduction in FHIT expression had a lower overall survival using univariate (P =.04, RR = 2.27) and multivariate (P =.013, RR = 4.41) analyses. CONCLUSION: Overexpression of p53 predicted a trend toward an improved prognosis, whereas no reduction in FHIT expression predicted a significantly poorer outcome in patients with advanced oropharyngeal cancer.  相似文献   
67.
BACKGROUND: Monitoring of kidney function is essential during chemotherapy. Serum creatinine is of limited value in early detection of renal insufficiency. The cystatin C level has been proved to be a good marker for detection of mild reduction in glomerular filtration rate. PURPOSE: To evaluate the validity of the pretreatment serum cystatin C level in predicting significant reduction of the glomerular filtration rate during the induction phase of chemotherapy. PATIENTS AND METHODS: Serum levels of cystatin C and creatinine and corrected creatinine clearance were assessed in 34 children with different types of malignancy just before the start of chemotherapy and again in 33 of them 1 month later. Patients were compared with 14 healthy controls of matched age and sex. RESULTS: Before chemotherapy, all patients when compared with controls had normal levels of cystatin C (P = 0.1) and creatinine (P = 0.62) and normal corrected creatinine clearance (P = 0.76). One month after chemotherapy, patients showed a significant increase in their cystatin C levels (P < 0.001) and a significant decrease in their corrected creatinine clearance (P < 0.001). However, creatinine levels did not change significantly (P = 0.65). Corrected creatinine clearance negatively correlated significantly with both cystatin C and creatinine levels (r = -0.622, P < 0.001; r = -0.346, P = 0.045, respectively) before chemotherapy and also 1 month after chemotherapy (r = -0.577, P < 0.001; r = -0.45, P = 0.009, respectively). When pretreatment levels of cystatin C and creatinine were used to predict patients who developed a reduction in corrected creatinine clearance of more than 20% after therapy, only the cystatin C level was statistically significant (P = 0.03). A cutoff point of 0.57 mg/L with sensitivity of 77.8%, specificity of 63%, and overall accuracy of 74% was suggested. CONCLUSIONS: Children with malignant diseases develop significant reduction in their glomerular filtration rate during the induction phase of chemotherapy, although their serum creatinine level may not change significantly. Cystatin C, as a more sensitive marker than creatinine for the assessment of glomerular filtration rate, can be used to predict patients who would have a higher risk of renal impairment during the induction phase of chemotherapy and who thus would require more frequent renal function assessment to consider adjustment of the chemotherapy dose if indicated.  相似文献   
68.
OBJECTIVES: The purpose of this research was to study the independent effect of the amino acid glutamine on preimplantation mouse embryo development in vitro. STUDY DESIGN: Two-cell stage mouse embryos were cultured in human tubal fluid medium in the presence and absence of 1 mmol/L of glutamine. Outcomes for morphology and cleavage rates were compared with Fisher's and Mann-Whitney's tests, respectively. RESULTS: Glutamine increased the proportion of embryos that developed to the blastocyst stage (86.4%) compared with those cultured without glutamine (59.1%) (P =.052). The percentages of embryos developing to the morula or hatching blastocyst stages were comparable in the 2 groups. Blastocyst total cell numbers were significantly higher in the glutamine group (34+/-1.7 vs 18.5+/-3.5, respectively; values are mean+/-SEM, P =.044). CONCLUSION: The amino acid glutamine independently improves preimplantation mouse embryo development in vitro. Further studies are needed to examine the applicability of these results to humans.  相似文献   
69.
The dissection of the descending aorta is a serious affection regarding to its mortality and its complications. It becomes chronic after the 14th day following the first signs of dissection. The authors report the case of a 55 years old patient who has presented a type III dissection diagnosed at the chronic period. The persistance of the pain has indicated the implantation of a stent at the intimal tear. This new endovascular treatement of the aorta diseases is a promising and less invasive alternative to the surgical treatement. It may reduce the morbidity and the mortality of this pathology but it needs an accurate and performant imaging techniques.  相似文献   
70.
Twenty International congresses for dermatology and sexually transmitted diseases were held between 1889 and 2002. The number of attendees and the subjects discussed during such congresses progressively increased in number and quality. The continuous progress and development in the knowledge presented year after year was a natural reflection of development in science, culture, and social standard of the countries that hosted these congresses. In this paper, we highlight the achievements of the great universal figures in dermatology who contributed to its progress, and the important milestones of scientific development that will remain as history and references for the future generation.  相似文献   
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