Combining technologies to create bioactive hybrid scaffolds for bone tissue engineering

Combining technologies to engineer scaffolds that can offer physical and chemical cues to cells is an attractive approach in tissue engineering and regenerative medicine. In this study, we have fabricated polymer-ceramic hybrid scaffolds for bone regeneration by combining rapid prototyping (RP), electrospinning (ESP) and a biomimetic coating method in order to provide mechanical support and a physico-chemical environment mimicking both the organic and inorganic phases of bone extracellular matrix (ECM). Poly(ethylene oxide terephthalate)-poly(buthylene terephthalate) (PEOT/PBT) block copolymer was used to produce three dimensional scaffolds by combining 3D fiber (3DF) deposition, and ESP, and these constructs were then coated with a Ca-P layer in a simulated physiological solution. Scaffold morphology and composition were studied using scanning electron microscopy (SEM) coupled to energy dispersive X-ray analyzer (EDX) and Fourier Tranform Infrared Spectroscopy (FTIR). Bone marrow derived human mesenchymal stromal cells (hMSCs) were cultured on coated and uncoated 3DF and 3DF + ESP scaffolds for up to 21 d in basic and mineralization medium and cell attachment, proliferation, and expression of genes related to osteogenesis were assessed. Cells attached, proliferated and secreted ECM on all the scaffolds. There were no significant differences in metabolic activity among the different groups on days 7 and 21. Coated 3DF scaffolds showed a significantly higher DNA amount in basic medium at 21 d compared with the coated 3DF + ESP scaffolds, whereas in mineralization medium, the presence of coating in 3DF+ESP scaffolds led to a significant decrease in the amount of DNA. An effect of combining different scaffolding technologies and material types on expression of a number of osteogenic markers (cbfa1, BMP-2, OP, OC and ON) was observed, suggesting the potential use of this approach in bone tissue engineerin

Latent profiles of telehealth care satisfaction during the COVID-19 pandemic among patients with cardiac conditions in an outpatient setting

BackgroundDuring the COVID-19 pandemic, telemedicine was advocated and rapidly scaled up worldwide. However, little is known about for whom this type of care is acceptable.ObjectiveTo examine which patient characteristics (demographic, medical, psychosocial) are associated with telehealth care satisfaction, attitude toward telehealth, and preference regarding telehealth over time in a cardiac patient population.MethodsIn total, 317 patients were recruited at the Elisabeth-TweeSteden Hospital in The Netherlands. All patients who had received telehealth care (telephone and video) in the previous 2 months were approached for participation. Baseline, 3-month, and 6-month questionnaires were administered online. A 3-step latent class analysis was conducted to identify trajectories of telehealth use over time and the possible association of the found trajectories with external variables.ResultsFive trajectories (classes) were identified for satisfaction with telehealth and 4 for attitude toward telehealth. Patients with higher distress, lower physical and mental health, higher scores on pessimism, and negative affectivity were more likely to be less satisfied. Patients with no partner, more comorbidities, higher distress, lower physical and mental health, and higher scores on pessimism were more likely to hold a negative attitude toward telehealth. For the future application of telehealth, marital status, comorbidities, digital health literacy, and pessimism were significantly related.ConclusionResults show that patients’ profiles should be considered when offering telehealth care and that the “one size fits all” approach does not apply. Results can inform clinical practice on how to better implement remote health care in the future while considering a personalized approach.<br/

1.19 Calcium Phosphate Ceramics With Inorganic Additives ☆

The use of inorganic compounds as synthetic growth factors is a promising approach for improving the biological properties of existing synthetic bone graft substitutes such as calcium phosphates. In this article we have described some of the inorganic additives that may improve the capabilities of calcium phosphates, and help bridge the gap toward autograft?s performance known as gold standard for bone regeneration. This article focuses on the specific roles of bioinorganics in processes related to bone formation and resorption and how these modify the biological properties of calcium phosphates, and finally provides insight into the future of this field

Ectopic osteoid and bone formation by three calcium-phosphate ceramics in rats, rabbits and dogs

Calcium phosphate ceramics with specific physicochemical properties have been shown to induce de novo bone formation upon ectopic implantation in a number of animal models. In this study we explored the influence of physicochemical properties as well as the animal species on material-induced ectopic bone formation. Three bioceramics were used for the study: phase-pure hydroxyapatite (HA) sintered at 1200°C and two biphasic calcium phosphate (BCP) ceramics, consisting of 60 wt.% HA and 40 wt.% TCP (β-Tricalcium phosphate), sintered at either 1100°C or 1200°C. 108 samples of each ceramic were intramuscularly implanted in dogs, rabbits, and rats for 6, 12, and 24 weeks respectively. Histological and histomorphometrical analyses illustrated that ectopic bone and/or osteoid tissue formation was most pronounced in BCP sintered at 1100°C and most limited in HA, independent of the animal model. Concerning the effect of animal species, ectopic bone formation reproducibly occurred in dogs, while in rabbits and rats, new tissue formation was mainly limited to osteoid. The results of this study confirmed that the incidence and the extent of material-induced bone formation are related to both the physicochemical properties of calcium phosphate ceramics and the animal model

Healthcare utilization in patients with first-time implantable cardioverter defibrillators (data from the WEBCARE study)

Background Knowledge of the level of healthcare utilization (HCU) and the predictors of high HCU use in patients with an implantable cardioverter defibrillator (ICD) is lacking. We examined the level of HCU and predictors associated with increased HCU in first‐time ICD patients, using a prospective study design. Methods ICD patients (N = 201) completed a set of questionnaires at baseline and 3, 6, and 12 months after inclusion. A hierarchical multiple linear regression with three models was performed to examine predictors of HCU.ResultsHCU was highest between baseline and 3 months postimplantation and gradually decreased during 12 months follow‐up. During the first year postimplantation, only depression (β = 0.342, P = 0.002) was a significant predictor. Between baseline and 3 months follow‐up, younger age (β = −0.220, P < 0.01), New York Heart Association class III/IV (β = 0.705, P = 0.01), and secondary indication (β = 0.148, P = 0.05) were independent predictors for increased HCU. Between 3 and 6 months follow‐up, younger age (β = −0.151, P = 0.05) and depression (β = 0.370, P < 0.001) predicted increased HCU. Between 6 and 12 months only depression (β = 0.355, P = 0.001) remained a significant predictor.  Conclusions Depression was an important predictor of increased HCU in ICD patients in the first year postimplantation, particularly after 3 months postimplantation. Identifying patients who need additional care and provide this on time might better meet patients’ needs and lower future HCU

Stimulatory effects of inorganic ions on osteogenesis in vitro

Introduction: Several studies demonstrated the effect of silicate ions (Si) on differentiation of bone precursor cells1,2, although its exact role in processes related to bone formation and remodeling is still incompletely understood. The focus of this work is to explore the effect of calcium and silicate ions on growth and osteogenic differentiation of human mesenchymal stem cells (hMSCs). This strategy may reduce the need for growth factors required to stimulate bone formation in regenerative approaches, decreasing the associated costs and overcoming stability issues. Materials and Methods In order to define the range of Si concentrations that are not toxic to cells, we performed a preliminary study varying Si concentrations from 0.00357mM to 4mM. The concentration of the Ca ions was selected based on the earlier study by Barradas et. al3. Cell culture media were supplemented by using sodium silicate (Na2SiO3) and/or calcium chloride dehydrate (CaCl2*2H2O) as Si and Ca precursors, respectively. hMSCs derived from bone marrow were seeded at a seeding density of 2.000 cells/cm2 and allowed to adhere overnight. Then, the medium was replaced by the appropriate supplemented medium and cells were cultured for 3, 7, 14 and 18 days. Basic and osteogenic media were used as negative and positive controls. Cell proliferation was evaluated by DNA quantification. hMSCs osteogenic gene expression was evaluated by Q-PCR. Results DNA quantification indicated an increase in cell number during the culture time for all the conditions. Results obtained by Q-PCR revealed a significantly higher expression of osteocalcin (OC) and bone morphogenetic protein-2 (BMP2) in cells cultured in media supplemented by both ions, as compared to media containing either Ca or Si alone. Discussion and Conclusions DNA quantification studies indicated that none of the selected concentrations had a negative influence on cell proliferation. The increase in osteogenic gene expression for cells cultured with both Ca and Si suggested a synergistic effect of the two ions on osteogenic differentiation of hMSCs. We further showed that cells cultured in the medium with the highest concentration of Ca (7.8mM) revealed a higher expression of the selected genes, which is in accordance with the earlier results by Barradas et al3. The obtained results suggest the importance of combining both ions, Ca and Si, for promoting the osteogenic differentiation of hMSCs. References 1. Hoppe A, Biomaterials 32: 2757-2774, 2011. 2. Beck Jr GR, Nanomedicine: Nanotechnology, Biology, and Medicine,1-11, 2011 3. Barradas AMC et al., Biomaterials 3205-3215, 2012. Acknowledgments The author thanks the Portuguese Foundation for Science and Technology (FCT) for the grant (SFRH/BD/69962/2010). Disclosures The authors have nothing to disclose

Candesartan Mediated Amelioration of Cisplatin-Induced Testicular Damage Is Associated with Alterations in Expression Patterns of Nephrin and Podocin

Nephrin and podocin are known to be closely related to the pharmacological effects of angiotensin-II receptor blocker (ARB). The objectives of this study were to investigate the role of nephrin and podocin using cisplatin-induced testicular damage and to evaluate the effect of ARB. At first, we evaluated the effects of cisplatin either alone or in combination with ARB candesartan on changes in expression patterns of nephrin and podocin in the rat testes. We then conducted in vitro studies to investigate the effects of angiotensin using cultured Sertoli cells, line TM4. As a result, the expression of nephrin and podocin was shown to localize around the basal membrane of seminiferous tubules. Treatment with cisplatin resulted in a marked decrease in the expression of nephrin and podocin and induced a shift of both proteins from linear to granular expression patterns, accompanying the increased apoptotic index in the testes; these changes were partially restored by the additional administration of candesartan. In vitro studies with TM4 revealed the angiotensin-II mediated expression changes of nephrin and podocin. These findings suggest that candesartan can prevent cisplatin-induced testicular damage by regulating expression patterns of the nephrin-podocin complex in the testes

E-Health to manage distress in patients with an implantable cardioverter-defibrillator: Primary results of the WEBCARE trial

Objective: The Web-based distress management program for patients with an implantable cardioverter-defibrillator (ICD; WEBCARE) was developed to mitigate distress and enhance health-related quality of life in ICD patients. This study investigated the treatment effectiveness at 3-month follow-up for generic and disease-specific outcome measures. Methods: Consecutive patients implanted with a first-time ICD from six hospitals in the Netherlands were randomized to either the "WEBCARE" or the "usual care" group. Patients in the WEBCARE group received a 12-week fixed, six-lesson behavioral treatment based on the problem-solving principles of cognitive behavioral therapy. Results: Two hundred eighty-nine patients (85% response rate) were randomized. The prevalence of anxiety and depression ranged between 11% and 30% and 13% and 21%, respectively. No significant intervention effects were observed for anxiety (β = 0.35; p = .32), depression (β = -0.01; p = .98) or health-related quality of life (Mental Component Scale: β = 0.19; p = .86; Physical Component Scale: β = 0.58; p = .60) at 3 months, with effect sizes (Cohen d) being small (range, 0.06-0.13). There were also no significant group differences as measured with the disease-specific measures device acceptance (β = -0.37; p = .82), shock anxiety (β = 0.21; p = .70), and ICD-related concerns (β = -0.08; p = .90). No differences between treatment completers and noncompleters were observed on any of the measures. Conclusions: In this Web-based intervention trial, no significant intervention effects on anxiety, depression, health-related quality of life, device acceptance, shock anxiety, or ICD-related concerns were observed. A more patient tailored approach targeting the needs of different subsets of ICD patients may be warranted. Trial registration: clinicaltrials.gov. Identifier: NCT00895700

Scaffolds with a standardized macro-architecture fabricated from several calcium phosphate ceramics using an indirect rapid prototyping technique

Calcium phosphate ceramics, commonly applied as bone graft substitutes, are a natural choice of scaffolding material for bone tissue engineering. Evidence shows that the chemical composition, macroporosity and microporosity of these ceramics influences their behavior as bone graft substitutes and bone tissue engineering scaffolds but little has been done to optimize these parameters. One method of optimization is to place focus on a particular parameter by normalizing the influence, as much as possible, of confounding parameters. This is difficult to accomplish with traditional fabrication techniques. In this study we describe a design based rapid prototyping method of manufacturing scaffolds with virtually identical macroporous architectures from different calcium phosphate ceramic compositions. Beta-tricalcium phosphate, hydroxyapatite (at two sintering temperatures) and biphasic calcium phosphate scaffolds were manufactured. The macro- and micro-architectures of the scaffolds were characterized as well as the influence of the manufacturing method on the chemistries of the calcium phosphate compositions. The structural characteristics of the resulting scaffolds were remarkably similar. The manufacturing process had little influence on the composition of the materials except for the consistent but small addition of, or increase in, a beta-tricalcium phosphate phase. Among other applications, scaffolds produced by the method described provide a means of examining the influence of different calcium phosphate compositions while confidently excluding the influence of the macroporous structure of the scaffolds