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Recently, attentions to the applications of biotechnology and nanotechnology in the polymer industries have been greater than before. Hybrid nanocomposites containing multi-type of nano structures are widely established, but application of biotechnology for in-situ embedment of nanoparticles in polymer matrix is rarely reported. In this study, poly (ethylene terephthalate) (PET) based ternary bionanocomposites containing modified chitosan (phosphorylated chitosan) and nanosilver particles were prepared by simple eco-friendly method. Chitosan was selected as a biopolymer with respect to the biological activity and compatibility with PET. Phosphorylation of chitosan was achieved in order to introduce the phosphorus moieties as a flame retardant agent in PET matrix by using chemical approach. Also a cost-effective and environmentally friendly method was used for the in-situ fabrication and decoration of silver nanoparticles on to phosphorylated chitosan in PET matrix. Effects of the hybrid system (phosphorylated chitosan and silver nanoparticles) on the morphology, thermal behavior and antibacterial properties of the PET samples were investigated by different methods. The microstructure and homogeneity of the samples were analyzed by studying of dispersion of nanoparticles in PET via scanning electron microscopy. The antibacterial properties of PET nanocomposites can be improved by insertion of silver nanoparticles into the bulk of polymer matrix. Obtained results indicated that the PET/phosphorylated chitosan/silver nanocomposites showed a significantly higher growth inhibition rate compared with the PET and PET/phosphorylated chitosan blend. Also the flame retardant properties of PET nanocomposites were drastically enhanced.

Background: Carotid angioplasty and stenting (CAS) is an accepted treatment to prevent stroke in patients with carotid artery stenosis. The purpose of this study is to identify risk factors for major complications after carotid angioplasty and stenting.Methods and Material: This is a prospective study conducted at Shiraz University of Medical Sciences in southern Iran from March 2011 to June 2014. Consecutive patients undergoing carotid angioplasty and stenting were enrolled. Both standard risk and high risk patients for endarterectomy were enrolled. Demographic data, atherosclerotic risk factors, site of stenosis, degree of stenosis, and data regarding technical factors were recorded. 30-day stroke, myocardial infarction, and/or death were considered as the composite primary outcome of the study.Results: two hundred and fifty one patients were recruited (mean age: 71.1+ 9.6 years, male: 65.3%). One hundred and seventy eight (70.9%) patients were symptomatic; 73 (29.1%), 129 (51.4%), 165 (65.7%) and 62 (24.7%) patients were diabetic, hyperlipidemic, hypertensive and smoker respectively. CAS performed for left ICA in 113 (45.4%) patients. 14 (5.6%) patients had Sequential bilateral stenting. Mean stenosis of operated ICA was 80.2 +13.8 %. Embolic protection device was used in 203 (96.2%) patients. Predilation and post-dilation were performed in 39 (18.5%) and 182 (86.3%) patients respectively. Composite outcome was observed in 3.6% (3.2% stroke, 0% myocardial infarction and 1.2% death). Left sided lesions and presence of DM was significantly associated with poor short term outcome. (P value: 0.025 and 0.020, respectively)Conclusion: There was a higher risk of short term major complications in diabetic patients and left carotid artery intervention.

Background: Carotid angioplasty and stenting (CAS) is an accepted treatment to prevent stroke in patients with carotid artery stenosis. The purpose of this study is to identify risk factors for major complications after CAS. Materials and Methods: This is a prospective study that was conducted at Shiraz University of Medical Sciences in southern Iran from March 2011 to June 2014. Consecutive patients undergoing CAS were enrolled. Both standard- and high-risk patients for endarterectomy were enrolled. Demographic data, atherosclerotic risk factors, site of stenosis, degree of stenosis, and data regarding technical factors were recorded. Thirty-day stroke, myocardial infarction, and/or death were considered as the composite primary outcomes of the study. Results: A total of 251 patients were recruited (mean age: 71.1 ± 9.6 years; male: 65.3%). Of these, 178 (70.9%) were symptomatic, 73 (29.1%) were diabetic, 129 (51.4%) were hyperlipidemic, 165 (65.7%) were hypertensive, and 62 (24.7%) patients were smokers. CAS was performed for left internal carotid artery (ICA) in 113 (45.4%) patients. Fourteen (5.6%) patients had sequential bilateral stenting. Mean stenosis of operated ICA was 80.2 ± 13.8%. An embolic protection device was used in 203 (96.2%) patients. Pre- and postdilation were performed in 39 (18.5%) and 182 (86.3%) patients, respectively. Composite outcomes were observed in 3.6% of patients (3.2% stroke, 0% myocardial infarction, and 1.2% death). Left-sided lesions and the presence of diabetes mellitus were significantly associated with poor short-term outcome (p = 0.025 and p = 0.020, respectively). Conclusion: There was a higher risk of short-term major complications in diabetic patients and for left carotid artery intervention.