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ObjectivesTo investigate the expression levels of multiple molecular markers in radical nephrectomy specimens from patients with metastatic renal cell carcinoma (RCC) treated with sorafenib in order to identify factors predicting susceptibility to this agent.Materials and methodsThis study included 45 consecutive patients undergoing radical nephrectomy for clear cell RCC who were diagnosed as having metastatic diseases refractory to cytokine therapy and subsequently treated with sorafenib. Expression levels of 19 molecular markers involved in the regulation of apoptosis, cell cycle, signal transduction, and angiogenesis in primary RCC specimens were measured by immunohistochemical staining.ResultsThere was no molecular marker having significant impact on the prediction of response to sorafenib. However, progression-free survival (PFS) was significantly associated with the expression levels of Bcl-xL and platelet-derived growth factor receptor (PDGFR)-α in addition to the presence of bone metastasis and C-reactive protein level on univariate analysis. Of these significant factors, PDGFR-α expression and the presence of bone metastasis appeared to be independently related to PFS by multivariate analysis. Furthermore, there were significant differences in PFS according to positive numbers of these 2 independent risk factors; that is, disease progression occurred in 2 of 7 patients who were negative for risk factor, 19 of 34 positive for a single risk factor, and 6 of 6 positive for both risk factors.ConclusionsCollectively, these findings suggest that it would be useful to consider expression levels of potential molecular markers, particularly PDGFR-α, as well as clinical parameters to select metastatic RCC patients likely to benefit from treatment with sorafenib.  相似文献   
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Pre-filled syringes (PFS) have been in widespread use as an administration device for therapeutic antibodies in recent decades. Generally, the inner barrel and syringe of PFS are coated with silicone oil (SO) for lubrication. Multiple studies have focused on the fact that the SO adsorbs denatured antibody molecules, and induces antibody aggregation. Aggregated antibodies are recognized as a potential risk for evoking immunogenic responses in patients. The characteristics of the aggregated antibody-SO complexes, including their concentration, population, shape, three-dimensional (3D) image, and Fcγ Receptors (FcγRs) activation have been obscurely acknowledged so far. In the present work, we prepared aggregated antibody-SO complexes by agitation and analyzed using multifaceted techniques such as flow imaging, confocal fluorescence microscopy, and cell-based assays for FcγRs activation. The results emphasized that the SO accelerates the increase in sub-visible particles and antibody aggregation. The confocal fluorescence microscopy analysis revealed the high-resolution 3D images of aggregated antibody-SO complexes. The FcγRs reporter cell assay clarified that the pre-mixed and agitated Ab + SO have higher FcγRs activation capability compared to the agitated Ab. Overall, this study advances the view that SO has an effect to increase the risk of agitation-induced aggregated antibody particles.  相似文献   
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Background: Inhibition of acetylcholinesterase (AChE), a biomarker of organophosphorous and carbamate exposure in environmental and occupational human health, has been commonly used to identify potential safety liabilities. So far, many environmental chemicals, including drug candidates, food additives, and industrial chemicals, have not been thoroughly evaluated for their inhibitory effects on AChE activity. AChE inhibitors can have therapeutic applications (e.g., tacrine and donepezil) or neurotoxic consequences (e.g., insecticides and nerve agents).Objectives: The objective of the current study was to identify environmental chemicals that inhibit AChE activity using in vitro and in silico models.Methods: To identify AChE inhibitors rapidly and efficiently, we have screened the Toxicology in the 21st Century (Tox21) 10K compound library in a quantitative high-throughput screening (qHTS) platform by using the homogenous cell-based AChE inhibition assay and enzyme-based AChE inhibition assays (with or without microsomes). AChE inhibitors identified from the primary screening were further tested in monolayer or spheroid formed by SH-SY5Y and neural stem cell models. The inhibition and binding modes of these identified compounds were studied with time-dependent enzyme-based AChE inhibition assay and molecular docking, respectively.Results: A group of known AChE inhibitors, such as donepezil, ambenonium dichloride, and tacrine hydrochloride, as well as many previously unreported AChE inhibitors, such as chelerythrine chloride and cilostazol, were identified in this study. Many of these compounds, such as pyrazophos, phosalone, and triazophos, needed metabolic activation. This study identified both reversible (e.g., donepezil and tacrine) and irreversible inhibitors (e.g., chlorpyrifos and bromophos-ethyl). Molecular docking analyses were performed to explain the relative inhibitory potency of selected compounds.Conclusions: Our tiered qHTS approach allowed us to generate a robust and reliable data set to evaluate large sets of environmental compounds for their AChE inhibitory activity. https://doi.org/10.1289/EHP6993  相似文献   
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