Strategies to Mitigate Biofouling of Nanocomposite Polymer-Based Membranes in Contact with Blood.

An extracorporeal blood purification method called continuous renal replacement therapy uses a porous hollow-fiber polymeric membrane that is exposed to prolonged contact with blood. In that condition, like with any other submerged filtration membrane, the hemofilter loses its properties over time and use resulting in a rapid decline in flux. The most significant reason for this loss is the formation of a biofilm. Protein, blood cells and bacterial cells attach to the membrane surface in complex and fluctuating processes. Anticoagulation allows for longer patency of vascular access and a longer lifespan of the membrane. Other preventive measures include the modification of the membrane itself. In this article, we focused on the role of nanoadditives in the mitigation of biofouling. Nanoparticles such as graphene, carbon nanotubes, and silica effectively change surface properties towards more hydrophilic, affect pore size and distribution, decrease protein adsorption and damage bacteria cells. As a result, membranes modified with nanoparticles show better flow parameters, longer lifespan and increased hemocompatibility.

Association of Arterial Tortuosity with Hemodynamic Parameters-A Computational Fluid Dynamics Study.

BACKGROUND: Tortuosity of intracranial arteries has been proven to be associated with the risk of intracranial aneurysm development. We decided to analyze which aspects of tortuosity are correlated with hemodynamics parameters promoting intracranial aneurysm development. METHODS: We constructed 73 idealized models of tortuous artery (length: 25 mm, diameter: 2.5 mm) with single bifurcation. For each model, on the course of segment before bifurcation, we placed 1-3 angles with measures 15, 30, 45, 60, or 75 degrees and arc lengths 2, 5, 7, 10, or 15 mm. We performed computational fluid dynamics analysis. Blood was modeled as Newtonian fluid. We have set velocity wave of 2 cardiac cycles. After performing simulation we calculated following hemodynamic parameters at the bifurcation: time average wall shear stress (TAWSS), time average wall shear stress gradient (TAWSSG), oscillatory shear index (OSI), and relative residence time (RRT). RESULTS: We found a significant positive correlation with number of angles and TAWSS (R = 0.329; P < 0.01), TAWSSG (R = 0.317; P < 0.01), and negative with RRT (R = -0.335; P < 0.0.01). Similar results were obtained in terms of arcs lengths. On the other hand, mean angle measure was negatively correlated to TAWSS (R = -0.333; P < 0.01), TAWSSG (R = -0.473 P < 0.01), OSI (R = -0.463; P < 0.01), and positively to RRT (R = 0.332; P < 0.01). On the basis of the obtained results, we developed new tortuosity descriptor, which considered angle measures normalized to its arc length and distance from bifurcation. For such descriptor we found strong negative correlation with TAWSS (R = -0.701; P < 0.01), TAWSSG (R = 0.778; P < 0.01), OSI (R = -0.776; P < 0.01), and positive with RRT (R = 0.747; P < 0.01). CONCLUSIONS: Hemodynamic parameters promoting aneurysm development are correlated with larger number of smaller angles located on larger arcs.

'Quality of life' concept in Cohesion Policy evaluation in Poland, 2004-2020.

Quality of life (QoL) is a fashionable concept widely used not only in many scientific fields but also in strategic documents, political speeches, and newspaper headlines. Although QoL is a crucial element of political agendas and a goal of public policies, there is little evidence on how this concept has been incorporated in policy analysis and evaluation. This study presents how the QoL has so far been defined, contextualised, and measured in the European Union Cohesion Policy evaluation in Poland, based on the analysis of 1431 evaluation reports for the period 2004-2020. The findings show that the interest in the QoL is growing, and almost one-third of reports refer to the term. However, the concept is usually not clearly defined, and the number of evaluations with actual questions concerning QoL is limited. Moreover, the methodological approach to QoL measurement is rudimentary, limited to surveys of beneficiaries or end-users.

Diabetes decreases patency of tunneled catheters in hemodialysis patients after first effective thrombolysis with urokinase.

INTRODUCTION: Fibrinolysis is one of the methods extending the use of vascular access in patients with tunneled venous catheters thrombosis. The aim of this study was to assess one-year maintenance of tunneled catheters patency after first effective thrombolysis with urokinase and identify its predictors. METHODS: Retrospective analysis included 85 patients (age 69 ± 13 years) with permanent venous catheter thrombosis treated with urokinase at one center in the period 2010-2016. Urokinase was used (depending on weight) at a dose of 10,000 or 20,000 IU in an 8 h infusion to each catheter line. Assessment of one-year efficacy of fibrinolysis included the time between fibrinolysis and following thrombosis of the same catheter in patients that have previously obtained at least partial blood flow. The analysis included medication, comorbidities, catheter patency time and INR value during first thrombosis episode. RESULTS: There were 62.4% patients with type-2 diabetes and 11.8% with neoplasm. The thrombolysis procedure was effective in 73 patients (85.9%). An analysis of the one-year efficacy of thrombolysis procedure included 73 patients. Among them, 23 experienced next episode of catheter-related thrombosis within a year postprocedure. Diabetes increased the risk for recurrent thrombosis [HR =3.19 (1.09-9.41); p = .03]. CONCLUSIONS: Patients with diabetes are at higher risk of recurrent catheter-related thrombosis and therefore may require more aggressive anticoagulation therapy for its prevention.