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Objective: In order to overcome the limitation of systemic administration of methylene blue, this study investigated the encapsulation of methylene blue in polymeric liposomes and drug release following sonication. Methods: We encapsulated methylene blue into nanoliposomes. The dynamic light scattering (DLS) method was used to measure the size distribution of the liposomes. After loading methylene blue into these liposomes, both drug encapsulation efficiency and stability were fluorometrically determined. Biodistribution of drug was studied in vivo in a mouse model of adenocarcinoma tumor cells. The amount of drug released upon 1 MHz sonication at an intensity of 2 W/cm² was fluorometrically verified in vitro.  Results: DLS studies showed that the synthesized liposomes had an average size of 66.19±4.49 nm. Methylene blue was efficiently encapsulated in nanoparticles at an average of 65.21±3.47%. Stability of the generated liposomes decreased with time. Biodistribution study revealed that the drug content in the group that received liposomal drugs in their tumor tissue was significantly higher than in the group that received methylene blue in its free form and in the heart was inverse (PConclusion: This study has shown that fabricated liposomes are suitable for the encapsulation and delivery of hydrophilic photosensitizers such as methylene blue. Ultrasound-triggered release was achieved by the use of a 1 MHz ultrasound.

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Compliance mismatch is one of the reasons of the coronary artery bypass graft (CABG) failure. The purpose of this study is to investigate the effect of compliance mismatch on the End to Side bypass graft. In order to model non Newtonian behavior of the blood flow, the Carreau–Yasuda model was employed and the graft and artery wall was assumed to be isotropic and modeled as a linearly elastic. In this study also the effects of blood rheology and wall distensibility on the wall shear stress distribution and velocity profile were investigated. The results of the simulation show that the maximum deformation occurs in the critical position of graft-artery junction and compliance mismatch cause smaller wall deformation in comparison to the cases in which the materials of the graft and artery are the same which leads to a higher intramural shear stress in graft-artery junction. The anastomotic wall deforms in a way that always tends to separate the graft and artery. Wall shear stress distribution on the bed centerline and the toe of the bypass graft indicates that the differences between the homologous and non-homologous material case are visible only when the internal pressure is lower than the external one. In the distal location of the artery after the toe of the anastomotic, the values of wall shear stress in the homologous material case are lower than the non-homologous material one.

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Objective: Pathological changes to endothelial cells of the vessel wall may lead to vascular stenosis. In this study, we investigate damages that appear following radiotherapy in two states, single fraction and fractionation irradiation, as an effective sign of cytoskeletal and nuclei structure of vascular wall endothelial cells.
Methods: We irradiated human vein endothelial cells (HUVECs) with a Cobalt-60 therapy machine at radiation doses of 0, 2, 4, and 8 Gy. We stained the skeletal structure of the membrane and nuclei within 24 h after irradiation. This cell line received fractionation radiation therapy at doses from 0 to 8 Gy, in sub-fractions of 2 Gy, after which we stained the cytoskeleton. Morphological parameters such as area and perimeter of the cells and nuclei were determined, and we evaluated the cell shape index (CSI) for cells from each group.
Results:  Increasing the irradiation dose from 0 to 8 Gy led to a significant decrease of CSI (approximately 56%) and a significant increase of nuclei shape index (approximately 85%; p<0.05). The cells’ areas and nuclei doubled (p<0.05). CSI parameter significantly decreased approximately 23% (4.5 times lower) during the radiotherapy fraction after application of the 8 Gy compared with control group cells.
Conclusion: After irradiation, we observed broken the membrane filaments that resulted in a new configuration, which led to increased cell and nuclei sizes along with alterations in the cell shape. Radiation therapy led to dose-dependent changes in morphological behavior response of the endothelial cells. Hence, it would be considered as a prognostic factor for behavior of healthy vascular cells in the process of radiotherapy.