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The biphasic calcium phosphate (BCP) concept was introduced to overcome disadvantages of single phase biomaterials. Different composition ratios of BCP bioceramics have been studied, yet controversies regarding the effects of ratio on biomaterial behavior still exist. In this study, BCP scaffolds were prepared from nano hydroxyapatite (HA) and β-tricalcium phosphate (β-TCP) that were synthesized via a solid state reaction. Three different composition ratios of pure BCP and collagen-based BCP scaffolds (%HA/%β-TCP; 30/70, 40/60, and 50/50) were produced using a polymeric sponge method. Physical and mechanical properties of all materials and scaffolds were investigated. SEM showed overall distribution of both macropores (80-200 μm) and micropores (0.5-2 μm) with high interconnected porosities. Total porosity of pure BCP (90% ± 3%) was found to be higher than collagen-based BCP (85% ± 2%). It was observed that following sintering process, dimensional shrinkage of large scaffolds (39% ± 4%) was lower than small ones (42% ± 5%) and scaffolds with high HA ratios (50%) experienced higher dimensional changes than those with higher β-TCP (70%) ratios (45% ± 3% and 36% ± 1%, respectively). Compressive strength of both groups was less than 0.1 MPa and collagen coating had almost no influence on mechanical behavior. Further studies may improve the physical properties of these scaffolds and investigate their exact biological behaviors.

The purpose of this study was to investigate liver and intestinal ABCA1 expression and plasma HDL-C level in response to treadmill-running training in rats. Twenty adult Wistar male rats (17-18 weeks old, 300-322 g) were divided into control (n = 10) and Training (n = 10) groups. Training group trained at 25 m/min (0% grade) for 60 min/day, 5 days/week for 12 weeks. Rats were killed 48 h after the last session of training. The intestinal and liver ABCA1 mRNA expression was found to be significantly higher in trained compared to control group (P < 0.006 and P < 0.024, respectively). Intestine and liver ATP concentrations remained unchanged. Plasma HDL-C, HDL2-C, Apo A-1, pre-beta HDL-C concentration, LCAT activity, TC/HDL-C and LDL-C/HDL-C ratio significantly increased in trained group (P < 0.01, P < 0.006, P < 0.001, P < 0.001 P < 0.067, P < 0.02, and P < 0.03, respectively). However, other lipoprotein concentrations were unchanged. In conclusion, we found that endurance training induced significant elevation in plasma HDL-C and HDL2-C concentrations, accompanied by higher plasma Apo A-1, pre-beta HDL-C concentrations, LCAT activity and ABCA1 mRNA expressions in rat intestine, and liver.

Calcium phosphate bioceramics nanoparticles such as nano‐hydroxyapatite (nHA) and nano‐tricalcium phosphate (nTCP) are the main focus of basic and applied research for bone tissue regeneration. In particular, a combination of these two phases (nHA + nTCP) which refers to as “nano‐biphasic calcium phosphates (nBCP)” is of interest due to the preferred biodegradation nature compared to single‐phase bioceramics. However, the available synthesis processes are challenging and the biomaterials properties are yet to be optimized to mimic the physiochemical properties of the natural nanoscale bone apatite. In this study, a new approach was developed for the production of optimized bioceramic nanoparticles aiming to improve their biomimecity for better biological performances. Nanoparticles were synthesized through a carefully controlled and modified wet mechano‐chemical method combined with a controlled solid‐state synthesis. Different processing variables have been analyzed including; milling parameters, post‐synthesis treatment, and calcination phase. Detailed physicochemical characterizations of nanoparticles revealed higher crystallinity (∼100%), lower crystallite/particle size (58 nm), higher homogeneity, reduced particle agglomeration size (6 μm), and a closer molar ratio (1.8) to biological apatite compared to control and standard samples. Furthermore, the study group was confirmed as calcium‐deficient carbonate‐substituted BCP nanoparticles (nHA/nβ‐TCP: 92/8%). As such, the introduced method can afford an easier and accurate control over nanoparticle physiochemical properties including the composition phase which can be used for better customization of biomaterials for clinical applications. The findings of this article will also help researchers in the further advancement of production strategies of biomaterials. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 1654–1666, 2019.

The data presented in this article are related to the research article entitled “Biphasic calcium phosphates bioceramics (HA/TCP): Concept, physicochemical properties and the impact of standardization of study protocols in biomaterials research” [1]. This article provides in depth study of BCP bone substitutes as valuable option in the field of tissue engineering. However, there are discrepancies in the literature regarding the ideal physicochemical properties of BCP and the ideal balance between different phase compositions for enhanced bone tissue engineering (M. Ebrahimi, M.G. Botelho, S.V. Dorozhkin, 2016; M. Ebrahimi, P. Pripatnanont, S. Suttapreyasri, N. Monmaturapoj, 2014) [1,2]. This is found to be mainly because of improper characterization of BCP bioceramics in basic studies and lack of standard study protocols in in vitro and in vivo research. This data article along with original article provide the basic data required for ideal characterization of BCP and other bioceramics in an attempt to provide basic standardized protocols for future studies.

Highlights Currently, no proven effective therapies or preventive vaccines for SARAS-CoV-2 exist. Effective vaccines against COVID-19 are urgently required to overcome the SARAS-CoV-2. Several approaches are underway for vaccines developed against SARS-CoV-2. Some clinical trials are launched in several countries.

This study aimed to evaluate in vitro biocompatibility of a composite of nanoscale biphasic calcium phosphate (BCP) and collagen (C) compared to pure BCP (P) in different composition ratios of nanohydroxyapatite to nano-β-tricalcium phosphate (HA/β-TCP). Each study group comprised of three ratios of BCP (30/70, 40/60, and 50/50). For evaluation of cellular response toward each ratio, mouse osteoblast (MC3T3-E1) cell line was cultivated on the scaffolds for 19 days. Analysis of cell proliferation, cell viability, cell attachment and morphology, alkaline phosphatase (ALP) activity, and osteocalcin synthesis were done on culture days 1, 3, 7, 13, 15, and 19, appropriately. The scanning electron microscopy showed that the osteoblasts attached successfully to scaffolds surfaces in both BCP groups and in all different ratios by spreading their filopodia and expressing similar viability that was confirmed by confocal laser scanning electron microscope. BCP scaffold (P3070) showed remarkable ALP activity, whereas BCP (P5050) showed highest osteocalcin activity. Collagen coating supported high cell proliferation on culture day 1 and possessed limited benefit restricted to early phase of cell differentiation. In conclusion, the fabricated nanoscale BCP scaffolds offered high biocompatibility and supported well the cell proliferation and differentiation regardless the composition ratio. Furthermore, higher ratio of TCP supported the early phase of cell proliferation, whereas higher HA ratio influenced the later phase. Finally, BCP scaffolds P5050 and C4060 were suggested as candidates for clinical applications.