Health-related quality of life of Adolescent and Young Adult Cancer Survivors before and during the COVID-19 pandemic::Longitudinal improvements on social functioning and fatigue

The health-related quality of life (HRQoL) among long-term Adolescent and Young Adult Cancer Survivors (AYACS) and an age- and sex-matched normative population was examined. Although the HRQoL of AYACS was worse compared to the normative population before and during the COVID-19 pandemic, the scores of AYACS improved over time in contrast to the normative population. Presumably, AYACS are used to adjusting their lives to stressful life events. Furthermore, the lockdown may have been beneficial for AYACS who face difficulties fully participating in society due to the impact of cancer. AYACS who encounter HRQoL issues could benefit from support interventions to empower them and build resilience

Thermoplastic elastomers based on strong and well-defined hydrogen-bonding interactions

In order to investigate the effects of strong and well-defined hydrogen bonding on the properties ofthermoplastic elastomers (TPEs), we have applied two distinct and strongly dimerizing 2-ureido-4-[1H]-pyrimidinone (UPy) quadruple hydrogen bonding units as physical crosslinker. While the UPy-groupsconsequently serve as the 'hard phase' or 'hard block' in these TPEs, an amorphous polyester has been used as the 'soft phase' or 'soft block'. The UPy-unit has been flanked with either a sterically demandingisophorone spacer or a linear hexamethylene, where these spacers have been derived from isophoronediisocyanate (IPDI) or hexamethylene diisocyanate (HDI), respectively. This difference on a molecularlevel leads to a homogeneous amorphous material in the IPDI-case (polymer 1) and to a nanophaseseparatedmaterial in the HDI-case (polymer 2) as revealed by AFM and DSC experiments. Apart fromthis distinctive difference in morphology and nanoscopic organization, the macroscopic properties ofboth materials are also fundamentally different. In linear stress-strain and DMTA experiments, thehomogeneous IPDI-material 1 shows rubber-like behavior at room temperature, while the mechanicalproperties are strongly temperature dependent. The nanophase-separated HDI-material 2 shows acombination of rubber and plastic behavior and displays a clear rubber-plateau between 0 °C and 50 °Cwith little temperature dependence. The apparent activation-energy of flow for the latter material,determined by multi-frequency DMTA, is 135 kJ mol–1

Thermoplastic elastomers based on strong and well-defined hydrogen-bonding interactions

In order to investigate the effects of strong and well-defined hydrogen bonding on the properties ofthermoplastic elastomers (TPEs), we have applied two distinct and strongly dimerizing 2-ureido-4-[1H]-pyrimidinone (UPy) quadruple hydrogen bonding units as physical crosslinker. While the UPy-groupsconsequently serve as the 'hard phase' or 'hard block' in these TPEs, an amorphous polyester has been used as the 'soft phase' or 'soft block'. The UPy-unit has been flanked with either a sterically demandingisophorone spacer or a linear hexamethylene, where these spacers have been derived from isophoronediisocyanate (IPDI) or hexamethylene diisocyanate (HDI), respectively. This difference on a molecularlevel leads to a homogeneous amorphous material in the IPDI-case (polymer 1) and to a nanophaseseparatedmaterial in the HDI-case (polymer 2) as revealed by AFM and DSC experiments. Apart fromthis distinctive difference in morphology and nanoscopic organization, the macroscopic properties ofboth materials are also fundamentally different. In linear stress-strain and DMTA experiments, thehomogeneous IPDI-material 1 shows rubber-like behavior at room temperature, while the mechanicalproperties are strongly temperature dependent. The nanophase-separated HDI-material 2 shows acombination of rubber and plastic behavior and displays a clear rubber-plateau between 0 °C and 50 °Cwith little temperature dependence. The apparent activation-energy of flow for the latter material,determined by multi-frequency DMTA, is 135 kJ mol–1

Exclusion of deep venous thrombosis with D-Dimer testing. Comparison of 13 D-Dimer methods in 99 outpatients suspected of deep venous thrombosis using venography as reference standard.

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The degradation and performance of electrospun supramolecular vascular scaffolds examined upon in vitro enzymatic exposure

To maintain functionality during in situ vascular regeneration, the rate of implant degradation should be closely balanced by neo-tissue formation. It is unknown, however, how the implant's functionality is affected by the degradation of the polymers it is composed of. We therefore examined the macro- and microscopic features as well as the mechanical performance of vascular scaffolds upon in vitro enzymatic degradation. Three candidate biomaterials with supramolecularly interacting bis-urea (BU) hard blocks ('slow-degrading' polycarbonate-BU (PC-BU), 'intermediate-degrading' polycarbonate-ester-BU (PC(e)-BU), and 'fast-degrading' polycaprolactone-ester-BU (PCL-BU)) were synthesized and electrospun into microporous scaffolds. These materials possess a sequence-controlled macromolecular structure, so their susceptibility to degradation is tunable by controlling the nature of the polymer backbone. The scaffolds were incubated in lipase and monitored for changes in physical, chemical, and mechanical properties. Remarkably, comparing PC-BU to PC(e)-BU, we observed that small changes in macromolecular structure led to significant differences in degradation kinetics. All three scaffold types degraded via surface erosion, which was accompanied by fiber swelling for PC-BU scaffolds, and some bulk degradation and a collapsing network for PCL-BU scaffolds. For the PC-BU and PC(e)-BU scaffolds this resulted in retention of mechanical properties, whereas for the PCL-BU scaffolds this resulted in stiffening. Our in vitro study demonstrates that vascular scaffolds, electrospun from sequence-controlled supramolecular materials with varying ester contents, not only display different susceptibilities to degradation, but also degrade via different mechanisms. STATEMENT OF SIGNIFICANCE: One of the key elements to successfully engineer vascular tissues in situ, is to balance the rate of implant degradation and neo-tissue formation. Due to their tunable properties, supramolecular polymers can be customized into attractive biomaterials for vascular tissue engineering. Here, we have exploited this tunability and prepared a set of polymers with different susceptibility to degradation. The polymers, which were electrospun into microporous scaffolds, displayed not only different susceptibilities to degradation, but also obeyed different degradation mechanisms. This study illustrates how the class of supramolecular polymers continues to represent a promising group of materials for tissue engineering approaches

D-dimeer en de diagnostiek van diep veneuze trombose: vergelijkend onderzoek van 13 D-dimeer bepalingen bij 99 patiënten met klinische verdenking op diepe veneuze trombose.

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In situ heart valve tissue engineering using a bioresorbable elastomeric implant - From material design to 12 months follow-up in sheep

The creation of a living heart valve is a much-wanted alternative for current valve prostheses that suffer from limited durability and thromboembolic complications. Current strategies to create such valves, however, require the use of cells for in vitro culture, or decellularized human- or animal-derived donor tissue for in situ engineering. Here, we propose and demonstrate proof-of-concept of in situ heart valve tissue engineering using a synthetic approach, in which a cell-free, slow degrading elastomeric valvular implant is populated by endogenous cells to form new valvular tissue inside the heart. We designed a fibrous valvular scaffold, fabricated from a novel supramolecular elastomer, that enables endogenous cells to enter and produce matrix. Orthotopic implantations as pulmonary valve in sheep demonstrated sustained functionality up to 12 months, while the implant was gradually replaced by a layered collagen and elastic matrix in pace with cell-driven polymer resorption. Our results offer new perspectives for endogenous heart valve replacement starting from a readily-available synthetic graft that is compatible with surgical and transcatheter implantation procedures

Factor V leiden mutation, prothrombin gene mutation, and deficiences in coagulation inhibitors associated with budd-chiari syndrome and portal vein thrombosis: results of a case-control study.

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