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11.

Objectives

A combination of platinum-based chemotherapy and radiotherapy is the standard treatment for nasopharyngeal carcinoma (NPC). However, the efficacy of chemotherapy has reached a plateau. Many autophagy studies suggest that autophagy can either promote or suppress to cancer progression. Thus, a role of autophagy in the acquisition of chemoradioresistance has recently been a notable event. Therefore, we examined the relationship between autophagy and chemotherapy in NPC.

Methods

The expression of Beclin 1 and microtubule-associated protein light chain 3 (LC3), a marker of autophagy, was determined by immunohistochemistry in the biopsy samples of patients with NPC before and after the first course of chemotherapy. Additionally, to investigate in the effect of autophagy suppression in chemotherapy, NPC cell line C666-1 cells were treated with cisplatin and/or chloroquine, an inhibitor of autophagy.

Results

The expression of Beclin 1 increased after chemotherapy in all patients. In NPC cell line C666-1, compared to cisplatin alone, combination therapy (cisplatin and chloroquine) reduced cell viability, and promoted cell apoptosis.

Conclusions

These results suggest that autophagy, represented by Beclin 1, is upregulated after chemotherapy in both in vitro and in vivo NPC studies. Inhibition of autophagy could therefore be new strategy for NPC treatment.  相似文献   
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Takayasu arteritis results in a variety of vascular symptoms, and there are some cases in which progressive vascular lesions require surgical intervention. We present a case with ascending aortic aneurysm, right common carotid artery stenosis, left common carotid artery occlusion and left subclavian artery stenosis caused by Takayasu arteritis that was successfully treated with total arch replacement and ascending aorta to right internal carotid artery bypass.  相似文献   
15.
Although the mortality rates of gastric cancer (GC) are gradually declining, gastric cancer is still the fourth leading cause of cancer-related death worldwide. This may be due to the high rate of patients who are diagnosed with GC at advanced stages. However, in countries such as Japan with endoscopic screening systems, more than half of GCs are discovered at an early stage, enabling endoscopic resection (ER). Especially after the introduction of endoscopic submucosal dissection (ESD) in Japan around 2000, a high en bloc resection rate allowing pathological assessment of margin and depth has become possible. While ER is a diagnostic method of treatment and may not always be curative, it is widely accepted as standard treatment because it is less invasive than surgery and can provide an accurate diagnosis for deciding whether additional surgery is necessary. The curability of ER is currently assessed by the completeness of primary tumor removal and the possibility of lymph node metastasis. This review introduces methods, indications, and curability criteria for ER of EGC. Despite recent advances, several problems remain unsolved. This review will also outline the latest evidence concerning future issues.  相似文献   
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The purpose of this study is to determine the incidence, clinical characteristics and risk factors of postradiation pelvic insufficiency fracture (PIF) in women with uterine cervical cancer. We reviewed the medical records of 126 patients who received definitive radiotherapy (RT) for uterine cervical cancer between 2003 and 2009 at our institution. Among them, 99 patients who underwent at least one computed tomography (CT) or magnetic resonance imaging of the pelvis during their follow-up at more than 6 months were included in this analysis. The relationship between the incidence of PIF and several patient- and treatment-related factors was analyzed. The median follow-up period was 21 months. Of the 126 patients, 33 (with a total of 50 lesions) were diagnosed with PIF. The 2-year cumulative incidence was 32%. Univariate analysis showed that age ≥70 years (P= 0.0010), postmenopausal state (P = 0.0013), and lower CT density of bone and bone marrow (P= 0.020) significantly related to PIF. In a multivariate analysis, of the 59 patients whose CT densities were evaluable, lower CT density was the only significant factor associated with PIF (P = 0.0026). In conclusion, postradiation PIFs were detected in a considerable number of patients after definitive RT for cervical cancer. Predisposing factors were older age, postmenopausal state, and decreased density of bone and bone marrow on CT.  相似文献   
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Background  

The usefulness of laparoscopic low anterior resection for middle and lower rectal cancer remains controversial.  相似文献   
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Objective  Coronary artery bypass grafting (CABG) in patients with left ventricular dysfunction has been considered to be a challenging operation. We assessed the early angiographic and long-term clinical and functional outcomes of patients with poor left ventricular function who underwent isolated CABG. Methods  We retrospectively reviewed the records of 78 patients with a poor left ventricular ejection fraction (35% or less) who underwent isolated CABG between January 1991 and November 2006. The mean age of the patients was 66.1 ± 9.4 years, and their mean New York Heart Association functional class was 3.1 ± 0.8. Their mean end-diastolic left ventricular diameter was 57.4 ± 8.1 mm, and their mean grade of mitral regurgitation was 0.7 ± 1.0. Early postoperative angiograms were performed at 32.5 ± 33.5 days after the operation. Interval echocardiographic data were analyzed, and the long-term survival rate was evaluated. Results  The average number of distal anastomoses per patient was 3.2 ± 1.1. The operative mortality rate was 7.7%. Stroke occurred in 1.3% of patients. The overall patency rates for arterial and venous grafts were 100% and 97.2%, respectively. The left ventricular ejection fraction significantly improved from 28.2% ± 5.1% to 34.4% ± 8.4%. Both the end-diastolic and end-systolic left ventricular dimensions significantly decreased from 57.4 ± 8.1 to 55.1 ± 8.8 mm and from 47.4 ± 8.4 to 45.1 ± 9.7 mm, respectively. The actuarial patient survival rate at 10 years was 73.1%. Conclusion  CABG in patients with left ventricular dysfunction was effective, with favorable early graft patency rates. The long-term outcome was also acceptable, with echocardiographic functional recovery.  相似文献   
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