Fabrication of Rosuvastatin-Incorporated Polycaprolactone -Gelatin Scaffold for Bone Repair: A Preliminary In Vitro Study

Objective: Rosuvastatin (RSV) is a hydrophilic, effective statin with a long half-life that stimulates bone regeneration.The present study aims to develop a new scaffold and controlled release system for RSV with favourable properties forbone tissue engineering (BTE).Materials and Methods: In this experimental study, high porous polycaprolactone (PCL)-gelatin scaffolds that containeddifferent concentrations of RSV (0 mg/10 ml, 0.1 mg/10 ml, 0.5 mg/10 ml, 2.5 mg/10 ml, 12.5 mg/10 ml, and 62.5 mg/10ml) were fabricated by the thermally-induced phase separation (TIPS) method. Mechanical and biological properties ofthe scaffolds were evaluated by Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM),compressive strength, porosity, MTT, alkaline phosphatase (ALP) activity, water contact angle, degradation rate, pHalteration, blood clotting index (BCI), and hemocompatibility.Results: SEM analysis confirmed that the porous structure of the scaffolds contained interconnected pores. FTIRresults showed that the RSV structure was maintained during the scaffold's fabrication. RSV (up to 62.5 mg/10 ml)increased compressive strength (16.342 ± 1.79 MPa), wettability (70.2), and degradation rate of the scaffolds. Scaffoldsthat contained 2.5 mg/10 ml RSV had the best effect on the human umbilical cord mesenchymal stem cell (HUC-MSCs)survival, hemocompatibility, and BCI. As a sustained release system, only 31.68 ± 0.1% of RSV was released fromthe PCL-Gelatin-2.5 mg/10 ml RSV scaffold over 30 days. In addition, the results of ALP activity showed that RSVincreased the osteogenic differentiation potential of the scaffolds.Conclusion: PCL-Gelatin-2.5 mg/10 ml RSV scaffolds have favorable mechanical, physical, and osteogenic propertiesfor bone tissue and provide a favorable release system for RSV. They can mentioned as a a promising strategy for boneregeneration that should be further assessed in animals and clinical studies

The Effect of Polyvinyl Alcohol Concentration on the Growth Kinetics of KTiOPO4 Nanoparticles Synthesized by the Co-precipitation Method

KTiOPO4 nanoparticles are known as the best candidates to be utilized for second-harmonic generation in multiphoton microscopes and bio labels. Size and shape are important and effective parameters to control the properties of nanoparticles. In this paper, we will investigate the role of capping agent concentration on the size and shape control of KTP nanoparticles. We synthesized KTP nanoparticles by the co-precipitation method. Polyvinyl alcohol with different mole ratios to titanium ion (1:3, 1:2, 1:1) was used as a capping agent. Products were examined by X-ray diffraction patterns and scanning electron microscopy analyses. The X-ray diffraction patterns confirmed the formation of the KTP structure. The biggest (56.36 nm) and smallest (39.42 nm) grain sizes were obtained by using 1:3 and 1:1 mole ratios of capping agent, respectively. Dumbly, spherical and polyhedral forms of KTP nanoparticles were observed by the change in capping agent mole ratio. The narrowest size distribution of KTiOPO4 nanoparticles was obtained at a 1:1 mole ratio of capping agent. Doi: 10.28991/HIJ-2020-01-04-06 Full Text: PD

Growth of KTiOPO₄ crystals by flux technique and their characterization

356-361Single crystals of KTiOPO4 (KTP) have been grown by flux technique using K6P4O13 flux. Crystals up to 3×2×1 mm3 in size were grown by slow cooling and spontaneous nucleation when high temperature solution was cooled down to room temperature with the rate of 7°C/h. The structure and quality of the grown crystals were characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) and Optical Transmission analysis. The surface morphology of the grown crystals was studied by scanning electron microscopy (SEM)

Vascular endothelial growth factor (VEGF) delivery approaches in regenerative medicine

The utilization of growth factors in the process of tissue regeneration has garnered significant interest and has been the subject of extensive research. However, despite the fervent efforts invested in recent clinical trials, a considerable number of these studies have produced outcomes that are deemed unsatisfactory. It is noteworthy that the trials that have yielded the most satisfactory outcomes have exhibited a shared characteristic, namely, the existence of a mechanism for the regulated administration of growth factors. Despite the extensive exploration of drug delivery vehicles and their efficacy in delivering certain growth factors, the development of a reliable predictive approach for the delivery of delicate growth factors like Vascular Endothelial Growth Factor (VEGF) remains elusive. VEGF plays a crucial role in promoting angiogenesis; however, the administration of VEGF demands a meticulous approach as it necessitates precise localization and transportation to a specific target tissue. This process requires prolonged and sustained exposure to a low concentration of VEGF. Inaccurate administration of drugs, either through off-target effects or inadequate delivery, may heighten the risk of adverse reactions and potentially result in tumorigenesis. At present, there is a scarcity of technologies available for the accurate encapsulation of VEGF and its subsequent sustained and controlled release. The objective of this review is to present and assess diverse categories of VEGF administration mechanisms. This paper examines various systems, including polymeric, liposomal, hydrogel, inorganic, polyplexes, and microfluidic, and evaluates the appropriate dosage of VEGF for multiple applications

The progressive trend of modeling and drug screening systems of breast cancer bone metastasis

Abstract Bone metastasis is considered as a considerable challenge for breast cancer patients. Various in vitro and in vivo models have been developed to examine this occurrence. In vitro models are employed to simulate the intricate tumor microenvironment, investigate the interplay between cells and their adjacent microenvironment, and evaluate the effectiveness of therapeutic interventions for tumors. The endeavor to replicate the latency period of bone metastasis in animal models has presented a challenge, primarily due to the necessity of primary tumor removal and the presence of multiple potential metastatic sites. The utilization of novel bone metastasis models, including three-dimensional (3D) models, has been proposed as a promising approach to overcome the constraints associated with conventional 2D and animal models. However, existing 3D models are limited by various factors, such as irregular cellular proliferation, autofluorescence, and changes in genetic and epigenetic expression. The imperative for the advancement of future applications of 3D models lies in their standardization and automation. The utilization of artificial intelligence exhibits the capability to predict cellular behavior through the examination of substrate materials' chemical composition, geometry, and mechanical performance. The implementation of these algorithms possesses the capability to predict the progression and proliferation of cancer. This paper reviewed the mechanisms of bone metastasis following primary breast cancer. Current models of breast cancer bone metastasis, along with their challenges, as well as the future perspectives of using these models for translational drug development, were discussed