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Since 5-fluorouracil (5-FU)-based chemotherapy has become standard adjuvant treatment for patients with node-positive colonic adenocarcinoma, there has arisen the need for predictive factors. Thymidylate synthase (TS) is a major target of 5-FU's action, and high TS expression in carcinoma cells could reduce its cytostatic effect. Both, a 28-base pair repeat polymorphism and a cytosine vs. guanine single nucleotide polymorphism in the promoter region of the TS gene are known to modulate its expression. All patients with a single, non-metachronous node-positive colonic adenocarcinoma who underwent a potentially curative resection at this institution in the years 1994-2002, and who received adjuvant 5-FU (n=95) were included in this study. Ninety-four of the 95 patients were successfully genotyped: 70 patients were classified as TS gene low-expressors (2R-2R, 2R-3C and 3C-3C), and 24 patients were classified as high-expressors (2R-3G, 3C-3G and 3G-3G). Contrary to the hypothesis, Kaplan-Meier survival analysis did not reveal any differences between the groups (power of 0.8 to detect an absolute survival difference >30%). In a Cox model, venous angioinvasion and the infiltrative pattern of tumour invasion were strong adverse factors. These results argue against a practical role for the TS gene repeat polymorphism or the C/G single nucleotide polymorphism as a predictive factor. However, by careful histopathological examination a high-risk group of node-positive patients can be defined that could be candidates for studies of alternative (more aggressive) adjuvant treatment. 相似文献
124.
Weber SU Schewe JC Lehmann LE Müller S Book M Klaschik S Hoeft A Stüber F 《Critical care (London, England)》2008,12(5):R128
Introduction
In transgenic animal models of sepsis, members of the Bcl-2 family of proteins regulate lymphocyte apoptosis and survival of sepsis. This study investigates the gene regulation of pro-apoptotic and anti-apoptotic members of the Bcl-2 family of proteins in patients with early stage severe sepsis. 相似文献125.
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The intermediate nerve is seldom identified as the site of tumor origin in cerebellopontine angle schwannomas. A 29-year-old man presented with a 6-month history of slowly progressive hearing loss and dizziness; facial nerve weakness was not observed clinically. Magnetic resonance imaging revealed a tumor in the left cerebellopontine angle region extending up to the geniculate ganglion and along the course of the superficial petrosal nerve. A CT scan showed enlargement of the facial nerve canal. Microsurgery was performed via an extended retrosigmoid approach. Intraoperative and electrophysiological findings identified the intermediate nerve as the site of tumor origin. 相似文献
127.
Combination of fluticasone propionate and salmeterol potentiates the suppression of cigarette smoke-induced IL-8 production by macrophages 总被引:1,自引:1,他引:0
Sarir H Mortaz E Karimi K Johnson M Nijkamp FP Folkerts G 《European journal of pharmacology》2007,571(1):55-61
Cigarette smoke is the major risk factor for the development of chronic obstructive pulmonary disease (COPD). Macrophages are suggested to orchestrate the chronic inflammatory response and tissue destruction associated with COPD by secreting interleukin (IL)-8, a major neutrophil chemoattractant. The combination of inhaled corticosteroids and long-acting beta(2)-adrenoceptor agonists are increasingly used as maintenance therapy in patients with COPD. The aim of this study was to determine whether combined fluticasone propionate, a corticosteroid, and salmeterol, a long-acting beta(2)-adrenoceptor agonist, can suppress IL-8 production by human macrophages. To mimic resident macrophages in the lung, human monocytes were cultured for 5 days in medium containing Granulocyte Macrophage Colony Stimulating Factor (GM-CSF) and Macrophage Colony Stimulating Factor (M-CSF). In human Monocyte-Derived Macrophages, we found that cigarette smoke medium strongly enhanced IL-8 release in a time- and concentration-dependent manner. IL-8 release by cigarette smoke was significantly suppressed in a concentration-dependent manner by fluticasone and salmeterol. Coincubation of the drugs potentiated the inhibitory effect on cigarette smoke medium-induced IL-8 production and longer preincubation times resulted in more IL-8 inhibition. Interestingly, preincubation of cells with suboptimal concentration of salmeterol for 4 h before fluticasone administration for 30 min potentiates the inhibitory effect of fluticasone on IL-8 release. In conclusion, combination therapy may provide benefits over monotherapy for the treatment of COPD patients. 相似文献
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The only way to resolve the dispute about the effectiveness of surgery versus radiation therapy for glomus tympanicum and jugulare tumors is adequate long-term studies. In a retrospective study with an average follow-up period of 15 years (range 11 to 23 years) we reassessed 11 patients with glomus tympanicum tumors and 11 patients with glomus jugulare tumors. Ten of 11 patients with glomus tympanicum tumor were tumor-free after surgery. A temporary facial palsy and an external meatal wall defect were the only surgical complications. The air-bone gap postoperatively closed to within 10 dB in three patients, to within 20 dB in six patients, and to more than 30 dB in one patient. Nine of 10 patients with glomus jugulare tumor receiving complete resection were tumor-free. Less than half the patients experienced new-onset cranial nerve function loss, and all made satisfactory recovery, eliminating the need for tracheostomy or gastrostomy. In two patients, the hearing could be preserved on the preoperative level, but the majority already presented with deafness. In the long-term, surgery remains a treatment of choice for glomus tympanicum tumors. It is also an extremely effective treatment with low morbidity for glomus jugulare tumors, including those with intracranial extension. 相似文献
130.
Lutz E Lehmann Stefan Schroeder Wolfgang Hartmann Oliver Dewald Malte Book Stefan U Weber Jens-Christian Schewe Frank Stüber 《European journal of cardio-thoracic surgery》2006,30(1):59-63
OBJECTIVE: Cardiac surgery causes induction and release of inflammatory mediators that may be regulated by genetic background. Macrophage migration inhibitory factor (MIF) is a proinflammatory mediator that is known to be up-regulated in patients undergoing cardiac operations. Here we analyzed genotype distribution and allele frequency of the MIF-173*G/C single nucleotide polymorphism (SNP) and MIF plasma levels in patients undergoing surgical revascularization with (on-pump, n=45) and without (off-pump, n=34) cardiopulmonary bypass (CPB). METHODS: Genotyping was performed using a real-time PCR-based system with a hybridization probe system specific for the MIF-173*G/C SNP. In on-pump patients, blood samples were drawn before start of CPB, after termination of CPB and 12h postoperatively. In off-pump patients, blood samples were collected before stabilizer placement, after removal of the stabilizer and 12h postoperatively. MIF levels were measured using ELISA technique. RESULTS: Genotype distribution and allele frequencies were comparable between on-pump and off-pump patients. When comparing patients according to MIF genotype, a significant increase of MIF plasma levels after completed coronary bypass grafting using CPB was found in patients heterozygous for the MIF-173*G/C SNP (p<0.05). Moreover, on-pump patients showed significantly decreased MIF plasma levels after 12h postoperatively (p<0.05). In off-pump patients, MIF plasma levels were not significantly different over the time-course and were independent of the genotype. CONCLUSIONS: Patients carrying the C-allele showed significantly increased levels of the proinflammatory cytokine MIF compared to G/G homozygous when revascularization was carried out using CPB. The G/C genotype may be associated with a severe inflammatory reaction and therefore preoperative screening could be beneficial for patients undergoing cardiac surgery using CPB. 相似文献