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51.
OBJECTIVES: The aim of the study was the assessment of the clinical, angiographic and procedural characteristics correlated with freedom from adverse events at 1 year in a real life setting of consecutive bifurcation lesions. BACKGROUND: Even if stent implantation has shown to be superior to conventional balloon angioplasty in most coronary lesions, bifurcation treatment with stent implantation both in main and in side branch (SB) still raises controversy. METHODS: We reviewed the results obtained in a prospective multicenter registry of 150 patients with 158 bifurcation lesions involving a SB of sufficient diameter to be treated, if necessary, with a polymer based paclitaxel eluting stent (PES, TAXUS). Two stents were used in 118 lesions (74.7%). Final kissing balloon inflation was performed in 87/118 lesions (73.7%) and in 30/40 lesions (75.0%) of the 2 and 1 stent group respectively. RESULTS: At 1-year clinical follow-up we observed 4 stent thromboses, all involving the SBs of the 2 stents group (2.7%). Unlike previous reports, revascularization involved the main vessel in the majority of patients (21/150, 14.0%). After an exploratory multivariable analysis the only parameter predictive of target lesion revascularization (TLR) (HR 0.52; CI 95% 0.11-0.86; p = 0.02) and target vessel revascularization (TVR) (HR 0.47; CI 95% 0.14-0.90; p = 0.03) was postprocedural main branch minimal lumen diameter (MB-MLD). CONCLUSIONS: In a real life setting of consecutive bifurcation lesions, thrombosis rate, concentrated in the SB and the 2-stents group, and need for target lesion revascularization remain higher than in less complex lesion subgroups treated with PES. No differences in immediate success and TLR were observed between 2 stents and 1 stent groups. The frequently observed suboptimal stent expansion and final MB-MLD predict 1 year revascularization.  相似文献   
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Endothelium is the first physiological barrier between blood and tissues and can be injured by physical or chemical stress, particularly by the drugs used in the cancer therapy. Paclitaxel and doxorubicin are frequently used anticancer drugs and their cardiac side effects are well observed in clinical setting. Their side effects on the endothelium are still not clear enough. There are few investigations assessing the damages elicited by the combination use of chemotherapy agents in animal experimental models. The purpose of this study was to examine and compare the side effects of doxorubicin and paclitaxel on endothelium in vivo. The drugs were administered weekly to rats via intraperitoneal injections singly or in combinations. Lastly, aorta endothelium was examined. The most familiar parts of the aorta endothelium are the nucleus, free ribosomes, Weibel-Palada granules, plasmalemmal vesicles, and clear basement membrane. Examination of the endothelium and the related structures revealed some clear degenerative findings. Notably, administration of a paclitaxel and doxorubicin combinations caused the most dramatic change in ultrastructure, which may disrupt many functions of the endothelium.  相似文献   
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Hyperthermia, the heating of tissue from 41 to 45?°C, has been shown to improve the efficacy of cancer therapy when used in conjunction with irradiation and/or chemotherapy. In this work, hydrogel nanocomposites have been developed that can control the delivery of both heat and a chemotherapeutic agent (e.g. paclitaxel). The nanocomposites studied involve a stealth, poly(ethylene glycol) (PEG)-based system comprised of PEG (n?=?1000) methyl ether methacrylate and PEG (n?=?400) dimethacrylate with iron oxide nanoparticles physically entrapped within the hydrogel matrices. The capability of the hydrogel nanocomposites to be heated in an alternating magnetic field was demonstrated. The heating of the hydrogel systems was dependent on the crosslinking of the hydrogel network where hydrogels with lower swelling ratios were found to heat to a greater extent than those with higher ratios. In addition, paclitaxel was shown to exhibit non-Fickian release from the hydrogel systems, with the amount of drug released dependent on the hydrogel network structure. Three cell lines: M059K (glioblastoma), MDA MB 231 (breast carcinoma), and A549 (lung adenocarcinoma) were exposed to paclitaxel only, hyperthermia only, and both paclitaxel and hyperthermia to determine if a synergistic cytotoxic effect was possible for these cell lines. The efficacy of paclitaxel was greater with hyperthermia for the A549 cells; however, the M059K and MDA MB 231 did not show the same response.  相似文献   
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A series of linoleic acid-modified glycol chitosan (LAGC) conjugates were synthesized and characterized by FTIR and 1H NMR. The effect of the amount of linoleic acid (LA) on the physicochemical properties of LAGC conjugates was investigated. The mean diameters of three LAGC nanoparticles determined by dynamic light scattering ranged from 204 to 289 nm. The critical aggregation concentration values of LAGC conjugates in aqueous solution were 0.0148, 0.0348, and 0.0807 mg/ml, respectively. Paclitaxel (PTX) was physically loaded into the LAGC nanoparticles by a dialysis method. The drug loading content and encapsulation efficiency of PTX-loaded LAGC (PTX-LAGC) nanoparticles increased with an increasing ratio of the hydrophobic LA to hydrophilic glycol chitosan in the conjugates. PTX-LAGC nanoparticles were almost spherical in shape observed by transmission electron microscopy. In vitro release revealed that PTX release from the nanoparticles was reduced as the LA substitution degree of LAGC conjugates increased. Compared with the commercial formulation Taxol, PTX-LAGC-1 nanoparticles exhibited comparable cellular uptake and cytotoxicity against HepG2 cells in vitro. Importantly, PTX-LAGC-1 nanoparticles demonstrated the stronger antitumor efficacy against hepatic H22 tumor-bearing mice than Taxol (p < 0.05). Therefore, glycolipid-like LAGC nanoparticles had a potential as delivery vehicles for tumor therapy.  相似文献   
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目的系统评价紫杉醇脂质体联合铂类治疗晚期食管癌的疗效和安全性。方法利用计算机检索PubMed,Embase,Cochrane Library,Web of Science,CNKI,VIP,WanFang Data等数据库,收集有关临床试验,检索时间为自建库至2019年7月。根据纳入和排除标准独立进行文献筛选、资料提取及质量评价。对于单臂试验采用StataSE 11.0软件合并效应量,采用RevMan 5.3软件对随机对照试验(RCT)进行Meta分析。结果共纳入13篇文献,其中6篇为紫杉醇脂质体(研究组)与紫杉醇(对照组)的RCT,另外7篇为紫杉醇脂质体单臂试验,共有患者713例。单臂试验中,研究组的合并客观缓解率为46%,95%CI(0.40,0.52);RCT中,研究组的客观缓解率与对照组相当[RR=1.08,95%CI(0.87,1.35),P=0.50],但研究组的呼吸困难、肌肉痛、恶心呕吐、皮肤潮红等不良反应发生率明显低于对照组(P<0.05)。结论紫杉醇脂质体与普通紫杉醇在治疗晚期食管癌的疗效类似,但前者不良反应明显减少。  相似文献   
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AIM: To investigate the specific mechanisms of intrinsic and acquired resistance to taxotere (TXT) in pancreatic adenocarcinoma (PAC). METHODS: MTT assay was used to detect the sensitivity of PAC cell line SUIT-2 and its sublines (S-007, S-013, S-020, S-028 and TXT selected SUIT-2 cell line, S2/TXT) to TXT. Mdr1 (P-gp), multidrug resistance associated protein (MRP), lung resistance protein (LRP) and beta-tubulin isotype gene expressions were detected by RT-PCR. The functionality of P-gp and MRP was tested using their specific blocker verapamil (Ver) and indomethacin (IMC), respectively. The transporter activity of P-gp was also confirmed by Rhodamine 123 accumulation assay. RESULTS: S-020 and S2/TXT were found to be significantly resistant to TXT(19 and 9.5-fold to their parental cell line SUIT-2, respectively). RT-PCR demonstrated strong expression of Mdr1 in these two cell lines, but weaker expression or no expression in other cells lines. MRP and LRP expressions were found in most of these cell lines. The TXT-resistance in S2-020 and S2/TXT could be reversed almost completely by Ver, but not by IMC. Flow cytometry showed that Ver increased the accumulation of Rhodamine-123 in these two cell lines. Compared with S-020 and SUIT-2, the levels of beta-tubulin isotype II, III expressions in S-2/TXT were increased remarkably. CONCLUSION: The both intrinsic and acquired TXT-related drug resistance in these PAC cell lines is mainly mediated by P-gp, but had no relationship to MRP and LRP expressions. The increases of beta-tubulin isotype II, III might be collateral changes that occur when the SUIT-2 cells are treated with TXT.  相似文献   
59.
Paclitaxel is a widely used chemotherapy drug for advanced laryngeal cancer patients. However, the fact that there are 20-40% of advanced laryngeal cancer patients do not response to paclitaxel makes it necessary to figure out potential biomarkers for paclitaxel sensitivity prediction. In this work, Hep2, a laryngeal cancer cell line, untreated or treated with lower dose of paclitaxel for 24 h, was applied to DNA microarray chips for gene and miR expression profile analysis. Expression of eight genes altered significantly following paclitaxel treatment, which was further validated by quantitative real-time PCR. Four up-regulated genes were ID2, BMP4, CCL4 and ACTG2, in which ID2 and BMP4 were implicated to be involved in several drugs sensitivity. While the down-regulated four genes, MAPK4, FASN, INSIG1 and SCD, were mainly linked to the endoplasmic reticulum and fatty acid biosynthesis, these two cell processes that are associated with drug sensitivity by increasing evidences. After paclitaxel treatment, expression of 49 miRs was significantly altered. Within these miRs, the most markedly expression-changed were miR-31-star, miR-1264, miR-3150b-5p and miR-210. While the miRs putatively modulated the mRNA expression of the most significantly expression-altered genes were miR-1264, miR-130a, miR-27b, miR-195, miR-1291, miR-214, miR-1277 and miR-1265, which were obtained by miR target prediction and miRNA target correlation. Collectively, our study might provide potential biomarkers for paclitaxel sensitivity prediction and drug resistance targets in laryngeal cancer patients.  相似文献   
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