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101.
Multi-parametric flow cytometry analysis is a reliable method for phenotypic and functional characterization of tumor infiltrating immune cells (TIIC). The isolation of infiltrating leukocytes from solid tumors can be achieved through various methods which can be both enzymatic and mechanical; however, these methods may alter cell biology. The aim of this study was to compare the effects of three tissue disaggregation techniques on TIIC biology in breast, kidney and lung tumor specimens. We therefore compared two enzymatic treatments using either collagenase type IA alone or in combination with collagenase type IV and DNase I type II, and one mechanical system (Medimachine?). We evaluated the impact of treatments on cell viability, surface marker integrity and proliferative capacity. We show that cell viability was not significantly altered by treatments. However, enzymatic treatments decreased cell proliferation; specifically collagenases and DNase provoked a significant decrease in detection of surface markers such as CD4, CD8, CD45RA and CD14, indicating that results of phenotypic studies employing these techniques could be affected. In conclusion, mechanical tissue disaggregation by Medimachine? appears to be optimal to maintain phenotypic and functional TIIC features.  相似文献   
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Deciding where to look is mandatory to explore the visual world. To study the neural correlates subserving the cognitive phase of self-initiated eye movements in humans, we tested 12 healthy participants, using event-related functional MRI. Changes in the frontal-cortical activity preceding voluntary saccades were studied when the participants freely decided the direction of a forthcoming saccade, compared with a condition in which they had only to prepare an externally cued saccade. Self-initiation of saccades, before their execution, was specifically associated with frontal-lobe activation in the dorsolateral prefrontal cortex, and in the right presupplementary eye field and frontal eye fields, suggesting the roles of these areas in the decision process of where to look when facing two possible visual targets.  相似文献   
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BACKGROUND/AIMS: Portosystemic shunting, whether surgical or transjugular intrahepatic, has been a cornerstone of therapy for Budd-Chiari syndrome. However, the long-term impact of shunt dysfunction remains unknown. We have assessed this long-term impact in patients with surgical shunting. METHODS: Thirty-nine consecutive patients operated on between 1978 and 2000 were analyzed using time-dependent multivariate Cox model. RESULTS: Median follow-up was 110 months. Prosthetic shunts and high preshunt portal venous pressure were predictors of subsequent shunt dysfunction. Among 19 patients with persistently patent shunt, as compared to 20 patients with shunt dysfunction, 1 versus 18 developed refractory ascites; 1 versus 7 had variceal bleeding; 7 versus 2 had encephalopathy; 3 versus 11 (55%) died or underwent liver transplantation; and 0 versus 10 died from end-stage liver disease. Shunt dysfunction was associated with a shorter survival (p=0.001). Out of 20 patients with shunt dysfunction, seven had successful revision of the shunt. None of these seven patients had refractory ascites after revision or died from end-stage liver disease. CONCLUSIONS: In patients with Budd-Chiari syndrome treated with portosystemic shunting, shunt dysfunction has a major impact on morbidity and mortality.  相似文献   
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OBJECTIVE: To report the main features of mesenteric ischemia related to giant cell arteritis (GCA). METHODS: We screened 13 French internal medicine tertiary care centers for their cases of patients exhibiting GCA-associated mesenteric ischemia during a 16-year period (1990-2006). Patients were included if they reported newly developed abdominal symptoms associated with histological proof of GCA-associated mesenteric vasculitis and/or radiological abnormalities consistent with GCA-associated mesenteric vasculitis. We performed a Medline search to identify previously reported cases of GCA-associated mesenteric ischemia. RESULTS: We included 6 original cases and 22 cases identified in the literature (mean age of the 28 patients: 72.4 +/- 7.1 yrs; women: 79%). GCA was histologically proven for all patients. In 12 patients GCA diagnosis preceded mesenteric inflammatory arteritis. Mesenteric ischemia occurred either soon after initiation of steroid therapy (n = 6, mean time to onset after starting steroid 12 +/- 11 days) or with a low-dose steroid regimen (n = 6, dosage 0-10 mg/day). In 16 other patients, the mesenteric involvement was the first manifestation of GCA. Only 6 patients (21%) reported cardiovascular risk factors. Clinical manifestations of GCA-associated mesenteric ischemia, as well as biological markers (mean C-reactive protein level 91 +/- 50 mg/l), were very nonspecific. Imaging explorations were performed for 14 patients and showed specific signs of vasculitis on the mesenteric artery in 10 (71%). Nineteen patients (68%) required laparotomy and 9 patients (33%) died. CONCLUSION: Early diagnosis and medical management of mesenteric GCA may ameliorate the severe prognosis of this possibly underdiagnosed complication.  相似文献   
107.
The pathological remodeling of the arterial wall in atherosclerosis involves protease activities, which play a major role in complications, through plaque rupture. Here, we investigated the release of active proteases by human carotid plaques in relation to (1) the degree of lesion complexity and (2) their compartmentalization between cap, core and media. Eighty human carotid endarterectomy specimens were dissected into culprit stenosing (CPs) and adjacent non-complicated/non-stenosing plaques (NPs). Thirty-five additional CPs were microdissected into cap, core and media. All specimens were compared to control non-atherosclerotic endarteries for the release of components of the plasminogen/plasmin system and matrix metalloproteinases (MMPs). Results show a greater release of the plasminogen activators (PAs), plasmin and active MMPs by CPs compared to NPs, whereas healthy arteries released even lower levels. Furthermore, we highlight a functional interaction between these proteases in human atherosclerotic tissues and more importantly, we demonstrate that the core constitutes the main source of protease activities within CPs. Together, these results suggest that CPs generate plasmin, mainly in the core, which could in turn participate in MMP activation and the onset of complications.  相似文献   
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INTRODUCTION: Radio-chemotherapy is the standard treatment for locally advanced unresectable pancreatic cancer (LAPC). Chemotherapy has been shown to be effective in the treatment of metastatic disease and we therefore evaluated its use as a first-line treatment for LAPC. PATIENTS AND METHODS: We carried out a retrospective analysis of all consecutive patients treated for LAPC (N=33) between July 1997 and April 2005, analysing the results of first-line chemotherapy (CT group) and radio-chemotherapy (RCT group) in this setting. RESULTS: The first-line treatment was RCT in six patients (18.3%) and CT in 26 patients (78.8%). Secondary treatment was administered to nine patients of CT group with well-controlled disease: "closure" radio-chemotherapy for seven patients (26.9%) and secondary resection for three (12%). After a median follow-up of 27 months, 23 patients died (69.7%). Overall survival was 13.8 months [95% CI: 10.1-19.4] for the whole population, 9.5 months [95% CI: 4.6-] for the RCT and 18.0 months [95% CI: 12.4-25.5] for the CT. Overall survival for the CT patients undergoing secondary surgery or "consolidation" radio-chemotherapy was 28.8 months [95% CI: 13.8-]. CONCLUSION: First-line chemotherapy is a valid option for LAPC treatment, making it possible to identify the patients who may benefit from secondary resection or radio-chemotherapy.  相似文献   
110.
AIM: Endovascular repair may represent an interesting alternative to open surgery for ruptured abdominal aortic aneurysms (AAA). This study evaluated the feasibility and short-term results of endovascular repair of ruptured AAA at our center. METHODS: Between April 2004 and December 2005, all patients admitted to our center for a ruptured AAA were considered for endovascular repair. Patients whose hemodynamic status was too unstable to permit a preoperative CT scan and patients with an unfavorable anatomy for endovascular repair underwent open surgery. Endovascular repair consisted in emergency placement of an aorto-uni-iliac endograft associated with a crossover femoro-femoral bypass and deployment of an occluder in the contralateral common iliac artery. Follow-up postoperative CT scans were obtained 1, 6, 12 and 18 months after intervention and then annually. Data concerning diagnosis, the operative risk, treatment, and follow-up were collated prospectively in a registry and were analyzed on an intention-to-treat basis. RESULTS: Between April 2004 and December 2005, 17 patients were admitted to our Department for a ruptured AAA. Ten patients (59 %) underwent emergency endovascular repair and were included in this study (8 men and 2 women, mean age 81 years, range 51-97). The mean duration of the operation was 167 +/- 37 min. The mean blood transfusion volume was 3 700 +/- 1 400 mL. The mean duration of hospitalization was 19 days (range: 9-60). Mortality at day 30 was 20% (2 patients): one death occurred on day 2 due to multi-organ failure in an 80-year-old patient and another death occurred on day 2 owing to myocardial infarction in an 87-year-old patient. Mean follow-up was 6 months. Late mortality occurred in 2 cases. No endoleaks were observed during follow-up. CONCLUSION: Our initial results using endografts for the repair of ruptured AAA were satisfactory, with a feasibility of 59% and an operative mortality of 20%. Randomized studies are necessary to determine the true value of endovascular repair of ruptured AAA compared to conventional open repair.  相似文献   
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