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81.
BACKGROUND: The combination therapy for non-small-cell lung cancer (NSCLC) with platinum-based treatment is well known, but its utility in elderly has not been explored systematically. AIM: To examine whether aging compromises survival or exacerbates toxicity in patients with advanced lung cancer receiving platinum-based treatment. METHODS: We performed a nested case-control study in a cohort of chemotherapy na?ve patients enrolled January 1998-December 2003. Cases were consecutive patients over 70 at diagnosis with stage III or IV NSCLC. Controls were a subset of patients under 70 years matched by stage and year in which they had been treated. All patients received Cisplatin (80 mg/m2) or Carboplatin (4-6 AUC), every 4 weeks, followed by Vinorelbine (30 mg/m2) for a maximum of six courses. The medical history, physical examination and tumor imaging evaluation were performed at baseline and then monthly. Survival was calculated by Kaplan-Meier method and log-rank test was used for survival comparisons. Chi-squared test was used to compare side effects in the two groups. RESULTS: A total of 419 patients were identified for the case-control study (205 elderly/214 young) with 3.6 cycles per patient, on average. The 2- and 3-year survival rates were 20.5% and 6.8% for elderly patients and 9.8% and 2.3% for younger patients (p=0.017 and 0.014, respectively for 2 and 3 years). The proportion of patients with adverse effects, either grade 3 or 4, was the same in both groups at 2 years (43.9% versus 43.9%; p=0.99). CONCLUSIONS: Although elderly patients may self-select or be selected to be healthier, our findings suggest that elderly patients currently undergoing chemotherapy for lung cancer do as well or better than younger patients. Elderly age alone should not preclude patients from receiving platinum-based chemotherapy, since it seems well tolerated and effective in non-small-cell lung cancer among elderly patients.  相似文献   
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Tissue factor (TF), the cell surface receptor for the serine protease FVIIa supports cell migration by interaction with the cytoskeleton. Intracellular signaling pathways dependent on the cytoplasmic domain of TF modify cell migration and may alter vascular remodeling. Vascular remodeling was analyzed in a femoral artery injury and a blood flow cessation model in mice with a targeted deletion of the 18 carboxy-terminal intracellular amino acids of TF (TF(Deltact/Deltact)) and compared with TF wild-type mice (TF(wt/wt)). Morphometric analysis revealed a decrease in the intima/media ratio after vascular injury in arteries from TF(Deltact/Deltact) compared with TF(wt/wt) mice (femoral artery injury: 2.4+/-0.3 TF(wt/wt) versus 0.6+/-0.3 TF(Deltact/Deltact), n=9 to 10, P=0.002; carotis ligation: 0.45+0.11 TF(wt/wt) versus 0.22+0.03 TF(Deltact/Deltact), n=12 to 14, P=0.09). This was caused by an increase in the media by 54% (P=0.04) in the femoral artery model and by 32% (P=0.03) after carotis ligation and was associated with an increased number of proliferating cells. Isolated aortic smooth muscle cells (SMCs) of TF(wt/wt) mice showed an increased migratory response toward the TF ligand active site-inhibited FVIIa that was abolished in TF(Deltact/Deltact) SMC. In contrast, the unstimulated proliferation rate was increased in TF(Deltact/Deltact) SMC compared with TF(wt/wt) SMCs. Thus, retention of SMCs attributable to a migratory defect and increased proliferation results in thickening of the media and in decrease in neointima formation after arterial injury. TF cytoplasmic domain signaling alters vascular remodeling and, thereby, may play a role in the development of restenosis, atherosclerotic disease, and neovascularization.  相似文献   
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Controversy remains regarding whether the seco-steroid hormone 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) enhances calcium and phosphate movement across the intestinal epithelial cell by facilitated diffusion or a vesicular transport mechanism. In this study we investigated whether membrane trafficking, as judged by confocal microscopy, was sufficiently rapid in comparison to hormone-stimulated uptake of phosphate (32P). Primary cultures of chick intestinal cells were established overnight either in Petri dishes (uptake studies) or chambered coverslips (confocal microscopy). Addition of 130 pM 1,25(OH)2D3 resulted in an apparent increase in 32P uptake within 1 min, relative to controls, that was statistically significant from 3-10 min of incubation. Using the endocytic marker dye, FM1-43, confocal microscopy revealed a profound decrease in membrane-associated fluorescence (apical> basal) within 10 s of hormone treatment, a return of fluorescence at 15-65 s, followed by another round of decreasing and increasing fluorescence. Between 3-9 min of incubation, fluorescence intensity increased 50% (apical region) and 20% (basal region) over control conditions. An antibody (Ab 099) directed against a putative membrane receptor for 1,25(OH)2D3 (1,25D3-MARRS) inhibited both 32P uptake, and changes in fluorescence. In addition, the protein kinase C (PKC) inhibitor, calphostin C, inhibited both 32P uptake and the observed 1,25(OH)2D3-mediated changes in fluorescence. At the microscopic level, calphostin C pretreatment abolished the very rapid redistribution of the endocytic marker dye, although a slight increase in fluorescence was still observed. We conclude that 1,25(OH)2D3-stimulated vesicular trafficking is mediated by the 1,25D3-MARRS protein, implicates a PKC signaling mechanism, and occurs in a time frame that is commensurate with a role in ion transport.  相似文献   
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Tissue factor (TF), the main initiator of the extrinsic coagulation cascade is expressed in atherosclerotic lesions and contributes to coronary thrombus formation in myocardial infarction (MI). Circulating TF reflects intravascular TF activation but also adds to prothrombotic activation. Because the G allele of the TF promotor polymorphism -603 A/G is associated with monocytic mRNA expression we evaluated its association with myocardial infarction, based on a recessive deleterious effect assumption. Patients with MI (MI; n=793) and age and sex matched control subjects without coronary artery disease (C; n=340) undergoing coronary angiography were included. In patients with MI, the -603 G (MI: 76%, C: 70%) allele was prevalent compared to the control group (P=-0.04). Multivariate analysis revealed an odds ratio of 1.44 (confidence interval 1.07-1.93). Carriage of the -603 G allele is associated with an increased risk for myocardial infarction. Because higher plasma TF concentrations are found in -603 G carriers enhanced TF expression may be the mechanism underlying this association.  相似文献   
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Objectives. The costs associated with traumatic injury are often exacerbated by the development of post-traumatic stress symptoms. However, it is unclear what decreases the development of post-traumatic symptoms over time. The aim of the present research was to examine the role of psychological symptoms and social group memberships in reducing the development of post-traumatic stress symptoms after orthopaedic injuries (OIs) and acquired brain injuries (ABIs). Design and Methods. A longitudinal prospective study assessed self-reported general health symptoms, social group memberships, and post-traumatic stress symptoms among participants with mild or moderate ABI (n= 62) or upper limb OI (n= 31) at 2 weeks (T1) and 3 months (T2) after injury. Results. Hierarchical regressions revealed that having fewer T1 general health symptoms predicted lower levels of T2 post-traumatic stress symptoms after OI but forming more new group memberships at T1 predicted lower levels of T2 post-traumatic stress symptoms after ABI. Conclusion. A focus on acquiring group memberships may be particularly important in reducing the development of post-traumatic stress symptoms after injuries, such as ABI, which result in long-term life changes. STATEMENT OF CONTRIBUTION: WHAT IS ALREADY KNOWN ON THIS SUBJECT?: ? Post-traumatic stress symptoms are a common outcome after accidental traumatic injury. ? Persistent post-traumatic stress symptoms can be a risk factor for the development of PTSD. WHAT DOES THIS STUDY ADD?: ? New insight into the contributions of general health symptoms and social group memberships in the development of post-traumatic stress symptoms after accidental injury. ? The development of post-traumatic stress symptoms over time is associated with higher levels of general health symptoms among individuals with orthopaedic injuries; They are associated with lower levels of social group memberships among individuals with acquired brain injuries.  相似文献   
89.
The triggering receptor expressed on myeloid cells 1 (TREM-1) has been implicated in the production of proinflammatory cytokines and chemokines during bacterial infection and sepsis. For downstream signal transduction, TREM-1 is coupled to the ITAM-containing adaptor DAP12. Here, we demonstrate that Bruton tyrosine kinase (Btk), a member of the Tec kinases, becomes phosphorylated upon TREM-1 triggering. In U937-derived cell lines, in which expression of Btk was diminished by shRNA-mediated knockdown, phosphorylation of Erk1/2 and PLCγ1 and Ca2? mobilization were reduced after TREM-1 stimulation. Importantly, TREM-1-induced production of the pro-inflammatory cytokines, TNF-α and IL-8, and up-regulation of activation/differentiation cell surface markers were impaired in Btk knockdown cells. Similar results were obtained upon TREM-1 stimulation of BMDCs of Btk(-/-) mice. The analysis of cells containing Btk mutants revealed that intact membrane localization and a functional kinase domain were required for TREM-1-mediated signaling. Finally, after TREM-1 engagement, TNF-α production by PBMCs was reduced in the majority of patients suffering from X-linked agammaglobulinemia (XLA), a rare hereditary disease caused by mutations in the BTK gene. In conclusion, our data identify Btk as a positive regulator in the ITAM-mediated TREM-1/DAP12 pathway and suggest its implication in inflammatory processes.  相似文献   
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Introduction and hypothesis  

This study evaluates the expression of estrogen receptor (ER) isoforms alpha (α) and beta (β) and progesterone receptor (PR) in vaginal and periurethral tissue in women with genital prolapse in relation to genital and lower urinary tract symptoms (LUTS).  相似文献   
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