Biomimetic Scaffolds Based on Mn-, Mg-, and Sr-Substituted Calcium Phosphates Derived from Natural Sources and Polycaprolactone.

The occurrence of bone disorders is steadily increasing worldwide. Bone tissue engineering (BTE) has emerged as a promising alternative to conventional treatments of bone defects, developing bone scaffolds capable of promoting bone regeneration. In this research, biomimetic scaffolds based on ion-substituted calcium phosphates, derived from cuttlefish bone, were prepared using a hydrothermal method.

effects of ascorbic acid on viability and metabolism of patients' osteosarcoma stem cells.

Stagnation in novelties of osteosarcoma (OS) treatment indicates the need for new therapeutic methods. OS cancer stem cells (OS-CSC) are taught to have the ability to self-renew and develop mechanisms of anticancer drug resistance, and this is why it is difficult to eradicate them. Their metabolism has been recognized as a potential target of therapeutic action.

Osteogenic differentiation of human mesenchymal stem cells on substituted calcium phosphate/chitosan composite scaffold.

Ionic substitutions are a promising strategy to enhance the biological performance of calcium phosphates (CaP) and composite materials for bone tissue engineering applications. However, systematic studies have not been performed on multi-substituted organic/inorganic scaffolds. In this work, highly porous composite scaffolds based on CaPs substituted with Sr, Mg, Zn and SeO ions, and chitosan have been prepared by freeze-gelation technique.

PCL-Coated Multi-Substituted Calcium Phosphate Bone Scaffolds with Enhanced Properties.

Ionic substitutions within the hydroxyapatite lattice are a widely used approach to mimic the chemical composition of the bone mineral. In this work, Sr-substituted and Mg- and Sr-co-substituted calcium phosphate (CaP) scaffolds, with various levels of strontium and magnesium substitution, were prepared using the hydrothermal method at 200 °C. Calcium carbonate skeletons of cuttlefish bone, ammonium dihydrogenphosphate (NHHPO), strontium nitrate (Sr(NO)), and magnesium perchlorate (Mg(ClO)) were used as reagents.

Selenite Substituted Calcium Phosphates: Preparation, Characterization, and Cytotoxic Activity.

The aim of this study was to prepare a biomimetic selenium substituted calcium phosphate system for potential application in osteosarcoma therapy. Calcium phosphate (CaP) systems substituted with selenite ions were prepared by the wet precipitation method, using biogenic CaCO (derived from cuttlefish bone), CO(NH)-HPO, and NaSeO·5HO as reagents. Starting reaction mixtures were prepared based on the formula for selenite-substituted hydroxyapatite, Ca(PO)(SeO)(OH), with Ca/(P + Se) molar ratio of 1.

Strontium substituted biomimetic calcium phosphate system derived from cuttlefish bone.

Biomimetic triphasic strontium-substituted calcium phosphate (CaP) powders were prepared by wet precipitation method at 50°C, using CaCO , (NH ) COH PO , and Sr(NO ) as reagents. Calcite was prepared from biogenic source (cuttlefish bone). The synthesized powders have been characterized by elemental analysis, Fourier transform infrared spectrometry, X-ray diffraction, Rietveld refinement studies and cell viability test.

Optimization of an ex vivo gene transfer to the hamstrings tendons muscle remnants: potential for genetic enhancement of bone healing.

Aim: To assess whether an adenoviral vector carrying the bone morphogenetic protein genes (Ad.BMP-2) can transduce human muscle tissue and direct it toward osteogenic differentiation within one hour.

Methods: This in vitro study, performed at the Department of Molecular Biology, Faculty of Science, Zagreb from 2012 to 2017, used human muscle tissue samples collected during anterior cruciate ligament reconstructions performed in St Catherine Hospital, Zabok.

Bone Tissue Engineering in a Perfusion Bioreactor Using Dexamethasone-Loaded Peptide Hydrogel.

The main goal of this study was the formation of bone tissue using dexamethasone (DEX)-loaded [COCH₃]-RADARADARADARADA-[CONH₂] (RADA 16-I) scaffold that has the ability to release optimal DEX concentration under perfusion force. Bone-marrow samples were collected from three patients during a hip arthroplasty. Human mesenchymal stem cells (hMSCs) were isolated and propagated in vitro in order to be seeded on scaffolds made of DEX-loaded RADA 16-I hydrogel in a perfusion bioreactor.

Tuning physicochemical and biological properties of chitosan through complexation with transition metal ions.

The synthesis of biologically active scaffolds is focused on the design of cell-sensitive surface by applying cell-adhesive proteins or bioceramic micro (nano) particles. The emerging new strategy for manipulating the biological properties lies in the modification by trace metals found in the living organism. In this work, we have prepared biocompatible chitosan hydrogels modified by copper (II) and zinc (II) ions through complexation interactions.

SAHAquines, Novel Hybrids Based on SAHA and Primaquine Motifs, as Potential Cytostatic and Antiplasmodial Agents.

We report the synthesis of SAHAquines and related primaquine (PQ) derivatives. SAHAquines are novel hybrid compounds that combine moieties of suberoylanilide hydroxamic acid (SAHA), an anticancer agent with weak antiplasmodial activity, and PQ, an antimalarial drug with low antiproliferative activity. The preparation of SAHAquines is simple, cheap, and high yielding.

Biomimetic design of bone substitutes based on cuttlefish bone-derived hydroxyapatite and biodegradable polymers.

Being a major component of bone tissue, hydroxyapatite is the most investigated calcium phosphate in the design and development of bone implants. The high brittleness and poor load-bearing properties have led researchers to manipulate hydroxyapatite performance by applying polymer or metal materials. The present study focuses on biomimetic approach of the hydroxyapatite synthesis from the cuttlefish bone in order to preserve highly porous structure.

Apigenin, a dietary flavonoid, induces apoptosis, DNA damage, and oxidative stress in human breast cancer MCF-7 and MDA MB-231 cells.

Apigenin is found in several dietary plant foods such as vegetables and fruits. To investigate potential anticancer properties of apigenin on human breast cancer, ER-positive MCF-7 and triple-negative MDA MB-231 cells were used. Moreover, toxicological safety of apigenin towards normal cells was evaluated in human lymphocytes.

Human Mesenchymal Stem Cells Differentiation Regulated by Hydroxyapatite Content within Chitosan-Based Scaffolds under Perfusion Conditions.

The extensive need for hard tissue substituent greatly motivates development of suitable allogeneic grafts for therapeutic recreation. Different calcium phosphate phases have been accepted as scaffold's components with positive influence on osteoinduction and differentiation of human mesenchymal stem cells, in terms of their higher fraction within the graft. Nevertheless, the creation of unlimited nutrients diffusion through newly formed grafts is of great importance.

Capacity of muscle derived stem cells and pericytes to promote tendon graft integration and ligamentization following anterior cruciate ligament reconstruction.

Purpose: The aim of this study is to examine the capacity of muscle tissue preserved on hamstring tendons forming candy-stripe grafts in order to improve tendon to bone ingrowth and ligamentization. We hypothesized that muscle tissue does possess a stem cell population that could enhance the healing process of the ACL graft when preserved on the tendons.

Methods: Human samples from gracilis and semitendinosus muscles were collected during ACL surgery from ten patients and from these tissue samples human muscle-derived stem cells and tendon-derived stem cells were isolated and propagated.

Expression of OCT-4 and SOX-2 in Bone Marrow-Derived Human Mesenchymal Stem Cells during Osteogenic Differentiation.

Aim: Determine the levels of expression of pluripotency genes OCT-4 and SOX-2 before and after osteogenic differentiation of human mesenchymal stem cells (hMSCs).

Methods: Human MSCs were derived from the bone marrow and differentiated into osteoblasts. The analyses were performed on days 0 and 14 of the cell culture.

Effect of UVC radiation on mouse fibroblasts deficient for FAS-associated protein with death domain.

Purpose: Ultraviolet (UV) radiation-induced apoptosis enabled us to study the mechanism of DNA damage and to investigate how cells avoid consequences of damaged DNA. Cells with extensive DNA damage activate extrinsic and intrinsic pathways of apoptosis. The extrinsic pathway is coupled to a FAS-associated protein with death domain (FADD), an adaptor protein molecule necessary for mediating apoptotic signals through the cell.

Cytotoxic activity of novel palladium-based compounds on leukemia cell lines.

Effective treatment methods for human leukemia are under development, but so far none of them have been found to be completely satisfactory. It was recently reported that palladium complexes have significant anticancer activity as well as lower toxicity compared with some clinically used chemotherapeutics. The anticancer activities of two novel palladium(II) complexes, [Pd(sac)(terpy)](sac)·4H2O and [PdCl(terpy)](sac)·2H2O, were tested against three human leukemia cell lines, Jurkat, MOLT-4, and THP-1, in comparison with cisplatin and adriamycin.