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81.
We explored the potential of Smac mimetics, which antagonize Inhibitor of Apoptosis (IAP) proteins, for chemosensitization of neuroblastoma (NB). Here, we report that Smac mimetics, e.g. BV6, prime NB cells for chemotherapeutics including the topoisomerase II inhibitor doxorubicin (DOX) and vinca alkaloids such as Vincristine (VCR), Vinblastine (VBL) and Vinorelbine (VNR). Additionally, BV6 acts in concert with DOX or VCR to suppress long-term clonogenic growth. While BV6 causes rapid downregulation of cellular IAP (cIAP)1 protein and nuclear factor-kappaB (NF-κB) activation, DOX/BV6- or VCR/BV6-induced apoptosis occurs independently of NF-κB or TNFα signaling, since overexpression of dominant-negative IκBα superrepressor or the Tumor Necrosis Factor (TNF)α-blocking antibody Enbrel fail to block cell death. Mechanistic studies reveal that Receptor-interacting protein (RIP)1 is required for DOX/BV6-, but not for VCR/BV6-induced apoptosis, since transient or stable knockdown of RIP1 or the pharmacological RIP1 inhibitor necrostatin-1 significantly reduce apoptosis. By comparison, VCR/BV6-mediated apoptosis critically depends on the mitochondrial pathway. VCR/BV6 cotreatment causes phosphorylation of BCL-2 during mitotic arrest, enhanced activation of BAX and BAK and loss of mitochondrial membrane potential (MMP). Additionally, overexpression of BCL-2 profoundly suppresses VCR/BV6-induced apoptosis. Thus, BV6 sensitizes NB cells to chemotherapy-induced apoptosis via distinct initial signaling mechanisms depending on the chemotherapeutic drug. These findings provide novel mechanistic insights into Smac mimetic-mediated chemosensitization of NB.  相似文献   
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Atropinic drugs are known to potentially induce physical and/or mental impairments in the elderly. The aim of this study was to investigate trends of atropinic exposure in patients ≥65 years in France between 2006 and 2015. A repeated cross‐sectional study was performed quarterly from January 1, 2006 to December 31, 2015, in the ‘Echantillon Généraliste des Bénéficiaires (EGB)’, a representative sample of the French population. Exposed patients were identified using the Anticholinergic Durán's list. Outcomes were rate of patients exposed to at least one atropinic drug (atropinic prevalence rate) and atropinic burden per patient (sum of atropinic burden scores). Interrupted time series were used to analyze the impact of market withdrawal of some drugs with atropinic properties during the period of the study. The number of patients ≥65 years registered in the EGB ranged from 75 611 in 2006 to 95 389 in 2015. Atropinic prevalence rate decreased significantly from 45.6% in 2006 to 33.2% in 2015 (?12.4%, slope significance P < 0.05). Subjects aged ≥85 years were the most exposed. Total atropinic burden decreased significantly between 2006 and 2015 (2.2 ± 1.7 in 2006; 2.0 ± 1.5 in 2015; slope significance P < 0.05), especially in patients ≥85 years. Market withdrawals for safety reasons of some atropinic drugs were significantly associated with a decrease in the atropinic prevalence rate (P < 0.05) and atropinic burden per patient (P < 0.05). In conclusion, atropinic drug exposure in the elderly significantly decreased in France between 2006 and 2015. This decrease can be partly explained by regulatory measures against some atropinic drugs.  相似文献   
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Low-level laser therapy (LLLT) is widely used in regenerative medicine and in dental therapy by virtue of its beneficial effects in a plethora of pathological conditions. In this study, the effect of a 980 nm diode laser on pre-osteoblasts proliferation has been evaluated, along with reactive oxygen species (ROS) production. We hypothesized that ROS were a key factor in LLLT-induced pre-osteoblasts proliferation, as it is known that ROS can induce the activation of many biological pathways, leading to cell proliferation, differentiation or apoptosis. Murine pre-osteoblasts MC3T3 cells were irradiated with different energy outputs (1–50 J) in the absence or presence of the antioxidant N-Acetyl-L-cysteine (NAC). Laser treatment, in the absence of NAC, was able to induce a fluence-dependent statistically significant increase in ROS generation, while the presence of NAC strongly inhibited it. Cell proliferation, measured after laser stimulation, was significantly increased both at low and higher energy, with a peak at 10 J in the absence of the antioxidant. On the contrary, in the presence of NAC, laser irradiation was not able to induce any cell proliferation, suggesting a crucial role of ROS in this laser-induced cell effect. These results suggest that LLLT may be a useful tool for bone regeneration therapy and an effective range of fluences to be used is indicated.  相似文献   
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We have previously shown that a single injection of rhBMP-7 (OP-1) applied to the regenerate early during distraction accelerates bone consolidation in a rabbit model of distraction osteogenesis. In the present study, we hypothesised that the injection of OP-1 improves bone consolidation by increasing blood flow to the distracted site. Blood flow into the regenerate of a rabbit model was measured and vascular endothelial growth factor (VEGF) expression was tested using semi-quantitative PCR. Immunohistochemistry was used for assessing the temporal and spatial expression of platelet endothelial cell adhesion molecule (PECAM), VEGF and its receptors following OP-1 injection. We observed a higher expression of VEGF and its receptors in the regenerate with OP-1 treatment. However, there was no difference in the increase in bone blood flow nor PECAM expression between the treated and control groups of animals. Interestingly, the increased expression of VEGF and its receptors was associated with chondrocyte and fibroblast-like cells, but not with endothelial cells. These results suggest that accelerated ossification by OP-1 may depend on a non-vascular mechanism, possibly involving a non-angiogenic function of VEGF signalling.  相似文献   
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Yang  Kun  Perez  Manuela  Hossu  Gabriela  Hubert  Nicolas  Perrenot  Cyril  Hubert  Jacques 《Surgical endoscopy》2017,31(1):100-106
Surgical Endoscopy - In robotic surgery, the professional ergonomic habit of using an armrest reduces operator fatigue and increases the precision of motion. We designed and validated a pressure...  相似文献   
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