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Osteoporotic-related fractures are among the leading causes of chronic disease morbidity in Europe and in the US. While a significant percentage of fractures can be repaired naturally, in delayed-union and non-union fractures surgical intervention is necessary for proper bone regeneration. Given the current lack of optimized clinical techniques to adequately address this issue, bone tissue engineering (BTE) strategies focusing on the development of scaffolds for temporarily replacing damaged bone and supporting its regeneration process have been gaining interest. The piezoelectric properties of bone, which have an important role in tissue homeostasis and regeneration, have been frequently neglected in the design of BTE scaffolds. Therefore, in this study, we developed novel hydroxyapatite (HAp)-filled osteoinductive and piezoelectric poly(vinylidene fluoride-co-tetrafluoroethylene) (PVDF-TrFE) nanofibers via electrospinning capable of replicating the tissue's fibrous extracellular matrix (ECM) composition and native piezoelectric properties. The developed PVDF-TrFE/HAp nanofibers had biomimetic collagen fibril-like diameters, as well as enhanced piezoelectric and surface properties, which translated into a better capacity to assist the mineralization process and cell proliferation. The biological cues provided by the HAp nanoparticles enhanced the osteogenic differentiation of seeded human mesenchymal stem/stromal cells (MSCs) as observed by the increased ALP activity, cell-secreted calcium deposition and osteogenic gene expression levels observed for the HAp-containing fibers. Overall, our findings describe the potential of combining PVDF-TrFE and HAp for developing electroactive and osteoinductive nanofibers capable of supporting bone tissue regeneration. In this study entitled "Hydroxyapatite-filled osteoinductive and piezoelectric nanofibers for bone tissue engineering", we describe the development of novel hydroxyapatite (HAp)-filled osteoinductive piezoelectric poly(vinylidene fluoride-cotetrafluoroethylene) (PVDF-TrFE) electrospun nanofibers as a potential strategy for supporting bone repair in delayed-union and non-union osteoporotic-related fractures, for which current clinical techniques have proven to be largely inadequate and scaffold-based tissue engineering approaches hold significant promise. While the piezoelectric properties of native bone tissue have been extensively discussed in the literature, including their key role in preserving tissue homeostasis and promoting tissue repair, they have been widely neglected in the design of scaffolds for bone tissue engineering (BTE) applications. Piezoelectric scaffolds can be used not only for mimicking the native piezoelectric features of bone but also to provide a platform for applying electrical or mechanical stimuli to damaged tissue, contributing to an accelerated regeneration process. The nanofibrous scaffolds generated in this study were capable of replicating the main electrical, structural and compositional properties of bone extracellular matrix (ECM). To the best of our knowledge, this was the first time that the combination of HAp with the piezoelectric polymer PVDF-TrFE was found to induce key shifts in the chemical structure of the polymer and promote β phase nucleation, not only enhancing the piezoelectric features of the constructs but also improving their surface properties, including their ability to support mineralization in vitro. The HAp nanoparticles also provided meaningful bone-like biological cues (osteoinduction), enhancing the osteogenic differentiation of seeded human mesenchymal stem/stromal cells (hMSCs), which was confirmed by an increased ALP activity, cellderived calcium deposition and expression of important osteogenic gene markers. Overall, our findings highlight, for the first time, the potential of combining PVDFTrFE and HAp for developing electroactive and osteoinductive nanofibrous constructs with improved piezoelectric properties, surface features and osteogenic potential capable of improving bone tissue regeneration. [ABSTRACT FROM AUTHOR]

The field of bioprinting is rapidly evolving as researchers innovate and drive the field forward. This chapter provides a brief overview of the history of bioprinting from the first described printer system in the early 2000s to present-day relatively inexpensive commercially available units and considers the current state of the field and emerging trends, including selected applications and techniques.

The Academic Research Consortium (ARC)-2 initiative revisited the clinical and angiographic end point definitions in coronary device trials, proposed in 2007, to make them more suitable for use in clinical trials that include increasingly complex lesion and patient populations and incorporate novel devices such as bioresorbable vascular scaffolds. In addition, recommendations for the incorporation of patient-related outcomes in clinical trials are proposed. Academic Research Consortium-2 is a collaborative effort between academic research organizations in the United States and Europe, device manufacturers, and European, US, and Asian regulatory bodies. Several in-person meetings were held to discuss the changes that have occurred in the device landscape and in clinical trials and regulatory pathways in the last decade. The consensus-based end point definitions in this document are endorsed by the stakeholders of this document and strongly advocated for clinical trial purposes. This Academic Research Consortium-2 document provides further standardization of end point definitions for coronary device trials, incorporating advances in technology and knowledge. Their use will aid interpretation of trial outcomes and comparison among studies, thus facilitating the evaluation of the safety and effectiveness of these devices.

Aims: Clinical data on the early and midterm outcomes of bioresorbable vascular scaffolds (BVS) in routine clinical practice are limited. To fill this gap, we report on the early and midterm clinical outcomes of PCI with everolimus-eluting BVS from the large multicentre GHOST-EU registry., Methods and Results: Between November 2011 and January 2014, 1,189 patients underwent percutaneous coronary intervention with one or more BVS (Absorb BVS; Abbott Vascular, Santa Clara, CA, USA) at 10 European centres. The primary outcome of interest was target lesion failure (TLF), defined as the combination of cardiac death, target vessel myocardial infarction, or clinically driven target lesion revascularisation (TLR). A total of 1,731 Absorb BVS were implanted at a mean of 12.3±3.4 atm. Technical success was achieved in 99.7% of cases. TLF was recorded in 67 of 1,189 patients at a median of 109 (interquartile range 8-227) days after implantation. The cumulative incidence of TLF was 2.2% at 30 days and 4.4% at six months. The annualised rate of TLF was 10.1%. At six months, the rate of cardiac death was 1.0%, target vessel myocardial infarction was 2.0%, TLR was 2.5%, and target vessel revascularisation was 4.0%. Diabetes mellitus was the only independent predictor of TLF (hazard ratio 2.41, 95% confidence interval: 1.28-4.53; p=0.006). The cumulative incidence of definite/probable scaffold thrombosis was 1.5% at 30 days and 2.1% at six months, with 16 of 23 cases occurring within 30 days., Conclusions: "Real-world" outcomes of BVS showed acceptable rates of TLF at six months, although the rates of early and midterm scaffold thrombosis, mostly clustered within 30 days, were not negligible.

Several absorbable nerve conduits are approved by the US Food and Drug Administration (FDA) and Conformit Europe (CE) for clinical repair of peripheral and cranial nerves . Surgeons are often not aware of the different(bio) materials of these conduits when performing nerve repair. An overview of these FDA- and CE-approved absorbable nerve conduits for clinical use is presented . PubMed, MEDLINE, and the companies selling the conduits were consulted . The available FDA and CE absorbable nerve conduits for peripheral and cranial nerve repair are 2 collagen- and 2 synthetic- polyester based conduits. The available clinical data, the price, the length, and the composition of the tube show significant differences. Based on the available data in this paper at this moment, we favor the PGA (Neurotube) nerve conduit for repair of peripheral and cranial nerve defects because of its advantages in length, price, and availability of clinical data. However, no prospective studies comparing the available nerve conduits have been published.

Several absorbable nerve conduits are approved by the US Food and Drug Administration (FDA) and Conformit Europe (CE) for clinical repair of peripheral and cranial nerves. Surgeons are often not aware of the different (bio)materials of these conduits when performing nerve repair. An overview of these FDA- and CE-approved absorbable nerve conduits for clinical use is presented. PubMed, MEDLINE, and the companies selling the conduits were consulted. The available FDA and CE absorbable nerve conduits for peripheral and cranial nerve repair are 2 collagen- and 2 synthetic-polyester-based conduits. The available clinical data, the price, the length, and the composition of the tube show significant differences. Based on the available data in this paper at this moment, we favor the PGA (Neurotube) nerve conduit for repair of peripheral and cranial nerve defects because of its advantages in length, price, and availability of clinical data. However, no prospective studies comparing the available nerve conduits have been published.