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PURPOSE: To evaluate the effect of lovastatin alone or combined with radiation on U87MG and FaDu cells in vitro and U87MG tumors in vivo. MATERIAL AND METHODS: Cell number, p21(WAF1) expression, apoptosis, reproductive cell death, and cell-cycle distribution were investigated after incubation of U87MG and FaDu cells in vitro. The effect of lovastatin (50 mg/kg/day) on tumor growth and on tumor growth delay after single-dose irradiation with 20 Gy was investigated using U87MG tumors in nude mice. RESULTS: Lovastatin dose dependently decreased cell number and proliferation of U87MG and FaDu cells. The proportion of cells in G0/G1 phase, apoptosis and p21 protein expression increased after lovastatin alone or combined with 4-Gy irradiation in both cell lines. Effects of lovastatin on cell cycle and cell number were more pronounced in U87MG compared to FaDu. No radiosensitization of clonogenic cells by lovastatin could be demonstrated in both cells lines, but the colony-forming ability after lovastatin alone was decreased in FaDu cells. In vivo, lovastatin decreased tumor volume over time but did not increase growth delay after irradiation of U87MG tumors with 20 Gy. CONCLUSION: The data support effects of lovastatin on proliferation, apoptosis and colony-forming ability in vitro and tumor volume in vivo. At the drug concentration achievable, lovastatin did not improve the effects of radiation on U87MG tumors in vivo.  相似文献   
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The results of hepatitis C virus (HCV) antibody test of 237, 813 blood donations collected from 143, 815 donors by the West Midlands Blood Transfusion Centre in 1993 were analyzed retrospectively in order to determine the seroconversion rate among established previously anti-HCV negative donors. Three hundred sixteen (0.22%; 1 in 455) donors were positive by the enzyme linked immunosorbent assay (ELISA) screening test and 34 (0.024%; 1 in 4, 230) donors were positive by ELISA and the Recombinant Immuno Blot Assay (RIBA). Three donors previously negative for HCV antibody reacted positively by both tests. The annual seroconversion rate was calculated as one in 35, 937 donors. This figure argues against limitation of HCV antibody screening to new blood donors. A further 45 donors negative on previous screening reacted positively by ELISA and were indeterminate by RIBA. Unexpectedly, lapsed blood donors first tested for HCV antibody in 1993 had high positive reaction rates by ELSA and RIBA, which was significantly (P < 0.001) higher than those of new donors. RIBA-positive reaction rate among ELISA-positive donors was significantly higher amongst males than females (P < 0.0011. © 1995 Wiley-Liss, Inc.  相似文献   
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The vasodilatation induced by acetylcholine (ACh) in a rabbit isolated perfused kidney was abolished when the tissue was exposed to cold ischemia for 72 h in Euro-Collins (EC) solution. This vasodilatation is due to the release of endothelium-derived relaxing factor (EDRF) from renal vasculature as evidenced by the attenuation following methylene blue pretreatment. When kidneys were preserved in EC solution containing UK 38 485, a thromboxane synthase inhibitor, or nicardipine, a calcium channel blocker, ACh-induced vasodilatation persisted after 72 h of cold ischemia. These results were taken as evidence of tissue protective activity of UK 38 485 and nicardipine and have promising implications for cadaveric kidney transplantation.This paper was presented at the 35th World Congress of the International Society of Surgery in Hong Kong in August 1993  相似文献   
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BACKGROUND: Direct insertion of the trocar is an alternative method to Veress needle insertion for the creation of pneumoperitoneum. The safety of direct disposable shielded trocar insertion for the creation of pneumoperitoneum was assessed by comparing with Veress needle insertion during laparoscopic cholecystectomy (LC). METHODS: One thousand five hundred patients undergoing LC with pneumoperitoneum were included in this study. In 470 patients the Veress needle insertion technique was used, and in 1,030 patients direct trocar insertion technique was used. Patients having indications for open trocar insertion were excluded from the study. RESULTS: Complication rate was significantly higher in the Veress needle group (14% versus 0.9%; P <0.01), and the two major complications, gastric perforation and iliac artery laceration, were also encountered in this group. CONCLUSIONS: Our results suggest that with a lower complication rate, direct insertion of the disposable trocar is a safe alternative to Veress needle insertion technique for the creation of pneumoperitoneum. Such an approach has further advantages such as less cost/instrumentation and rapid creation of pneumoperitoneum.  相似文献   
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Three cases of intravenous leiomyomatosis (IVL) of the uterus, a rare benign smooth-muscle tumor, are described. A preoperative diagnosis of IVL was not made in any of the patients, all of which presented with a pelvic mass with the presumptive diagnosis of leiomyoma. Surgical exploration confirmed the presence of uterine mass and two of the three cases showed extra-uterine extension into the ovarian or uterine veins. Histological examination demonstrated a fascicular pattern of bland spindle-shaped smooth-muscle cells, which extended to veins inside the myometrium or to extrauterine veins. This was confirmed by immunohistochemical stain for desmin and factor VIII. Despite their histological benignity, these lesions have a tendency to metastasize and are closely related to the conditions called “benign metastasizing leiomyoma” and “intracaval mass and cardiac extension”. The primary treatment of IVL is hysterectomy and excision of any extrauterine tumor, when technically feasible. Anti-estrogenic therapy has been suggested as potentially useful in controlling of unresectable tumor. According to the literature, the follow-up must be long and periodic postoperative ultrasonic or magnetic nuclear resonance imaging studies may be useful in detecting growth of residual intravascular tumor.  相似文献   
8.
Background: The management of cholangiocarcinoma is continually reviewed on a current evidence basis to develop practice guidelines and consensus statements. However, the standardized treatment guidelines are still unclear for cholangiocarcinoma patients who are listed for liver transplantation. We aimed to validate and evaluate the potential efficacy of chemotherapy combination of Gemcitabine and Cisplatin as a neo-adjuvant treatment for cholangiocarcinoma patients before liver transplantation. Methods: In this prospective case series, patients with locally advanced, unresectable, hilar, or intrahepatic cholangiocarcinoma with no evidence of extrahepatic disease or vascular involvement were treated with a combination of neoadjuvant gemcitabine and cisplatin with no radiation. All patients included received chemotherapy prior to being listed for liver transplantation at a single cancer center according to an open-labeled, and center-approved clinical management protocol. The primary endpoints were the overall survival and recurrence-free survival after liver transplantation. Results: Between 1 March 2016, and 15 March 2022, 10 patients (8 males and 2 females) with a median age of 62.71(interquartile range: 60.02–71.87) had a confirmed diagnosis of intrahepatic or hilar cholangiocarcinoma and underwent liver transplantation. Median days of neoadjuvant therapy for a given combination of gemcitabine and cisplatin were 181 (IRQ: 120–250). Nine patients (90%) were reported with no recurrence or metastasis, and only 1 patient had confirmed metastasis (10%); days for metastasis after transplantation were 612 for this patient. All patients received a combination of gemcitabine and cisplatin as neo-adjuvant while awaiting liver transplantation. The median days of follow-up were 851 (813–967). Overall survival was 100% (95% CI 100–100%) at both years one and two; 75% (95% CI 13–96%) at years three to five. One patient died at eight hundred and eighty-five days. No adverse events were reported after liver transplantation including the patient who was confirmed with recurrence. Conclusions: Our finding demonstrated that neo-adjuvant gemcitabine and cisplatin with no radiation prior to liver transplantation resulted in excellent outcomes for patients with cholangiocarcinoma.  相似文献   
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The measurement of water diffusion by diffusion‐weighted MRI (DWI) in vivo offers a non‐invasive method for assessing tissue responses to anti‐cancer therapies. The pathway of cell death after anti‐cancer treatment is often apoptosis, which leads to accumulation of mobile lipids detectable by 1H MRS in vivo. However, it is not known how these discrete MR markers of cell death relate to each other. In a rodent tumour model [i.e. ganciclovir‐treated herpes simplex thymidine kinase (HSV‐tk) gene‐transfected BT4C gliomas], we studied the interrelationships between water diffusion (Trace{D}) and mobile lipids during apoptosis. Water diffusion and water‐referenced concentrations of mobile lipids showed clearly increasing and interconnected trends during treatment. Of the accumulating 1H MRS‐visible lipids, the fatty acid ? CH ?CH ? groups and cholesterol compounds showed the strongest associations with water diffusion (r2 = 0.30; P < 0.05 and r2 = 0.48; P < 0.01, respectively). These results indicate that the tumour histopathology and apoptotic processes during tumour shrinkage can be interrelated in vivo by DWI of tissue water and 1H MRS of mobile lipids, respectively. However, there is considerable individual variation in the associations, particularly at the end of the treatment period, and in the relative compositions of the accumulating NMR‐visible lipids. The findings suggest that the assessment of individual treatment response in vivo may benefit from combining DWI and 1H MRS. Absolute and relative changes in mobile lipids may indicate initiation of tumour shrinkage even when changes in tissue water diffusion are still small. Conversely, greatly increased water diffusion probably indicates that substantial cell decomposition has taken place in the tumour tissue when the 1H MRS resonances of mobile lipids alone can no longer give a reliable estimate of tissue conditions. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
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