ABSTRACT
<p><b>BACKGROUND</b>Breast cancer has become one of the most common malignant tumors among females over the past several years. Breast carcinogenesis is a continuous process, which is featured by the normal epithelium progressing to premalignant lesions and then to invasive breast cancer (IBC). Targeting premalignant lesions is an effective strategy to prevent breast cancer. The establishment of animal models is critical to study the mechanisms of breast carcinogenesis, which will facilitate research on breast cancer prevention and drug behaviors. In this study, we established a feasible chemically-induced rat model of premalignant breast cancer.</p><p><b>METHODS</b>Following the administration of the drugs (carcinogen, estrogen, and progestogen) to Sprague-Dawley (SD) rats, tumors or suspicious tumors were identified by palpation or ultrasound imaging, and were surgically excised for pathological evaluation. A series of four consecutive steps were carried out in order to determine the carcinogen: 7,12-dimethylbenzaanthracene (DMBA) or 1-methyl-1-nitrosourea, the route of carcinogen administration, the administration period of estrogen and progestogen, and the DMBA dosage.</p><p><b>RESULTS</b>Stable premalignant lesions can be induced in SD rats on administration of DMBA (15 mg/kg, administered three times) followed by administration of female hormones 5-day cycle.</p><p><b>RESULTS</b>were confirmed by ultrasound and palpation.</p><p><b>CONCLUSION</b>Under the premise of drug dose and cycle, DMBA combined with estrogen and progestogen can be used as a SD rat model for breast premalignant lesions.</p>
Subject(s)
Animals , Female , Rats , 9,10-Dimethyl-1,2-benzanthracene , Breast Diseases , Disease Models, Animal , Mammary Neoplasms, Experimental , Rats, Sprague-DawleyABSTRACT
Objective: To investigate the role of oxygen free radicals in renal dysfunction of rats with obstructive jaundice and the protective effect of reduced glutathione on renal mitochondria. Methods: Fifty-four Wistar rats were randomly divided into three groups: sham-operation control group (group A), obstructive jaundice group (group B), reduced glutathione treated group (group C). The model of obstructive jaundice in rats was established by common bile duct ligation (CBDL). In group C, reduced glutathione (150mg/kg.d) was given through abdominal cavity for 21 days. The rats were executed at 7th, 14th, and 21st day after operation respectively. The contents of serum BIL, Cr, BUN and the contents of renal mitochondria MDA and cholesterol were detected respectively, and the changes of renal histopathology were observed. Results: The contents of renal mitochondria MDA and cholesterol in group B and group C were markedly higher than group A (P
ABSTRACT
Objective: To investigate the feasibility and advantages of supraclavicular approaching thyroidectomy for benign thyroid diseases. Methods: From February 2004 to December 2007, 64 cases of thyroidectomies were performed via the lateral cervical supraclavicular incision, and were selected as experimental group, of whom, there were 37 cases of thyroid adenomas and 27 cases of nodular thyroid goiters, respectively. At the same time period, 63 cases of consecutive thyroidectomies through the conventional anterior neck incision were selected as a control group, of whom, there were 39 cases of thyroid adenomas and 24 cases of nodular thyroid goiters, respectively. Results: All the operations in two groups were successfully accomplished. In the experimental group, there were 9 subtotal thyroidetomies, 40 subtotal lobectomies and 15 nodulectomies. While in the control group, there were 8 total thyroidetomies, 37 subtotal lobectomies and 18 nodulectomies. The statistical analysis between the two groups was carried out in terms of tumor size, operative time-consuming, blood loss, postoperative drain volume, time for return of motion and postoperative complications. There were no injuries of laryngeal recurrent nerve, superior laryngeal nerve and parathyroid glands. Two cases of postoperative complications in the experimental group and 3 in the control group were observed, respectively, the statistical differences were not significant between the two groups. Conclusion: The supraclavicular incision for thryoidectomy for benign thyroid diseases is a feasible and safe technique with a satisfactory cosmetic result. It is accessible to the treatment of bilateral thyroid diseases and can facilitate the detection of lymphatic metastases.