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A novel self-hardening α-tricalcium phosphate (α-TCP) bone cement complexed with different content of α-calcium sulfate hemihydrate (α-CSH) and micrometer hydroxyapatite mineralized silk fibroin (HA-SF) using micro/SF as curing liquid has been investigated in this work, which was capable of tunable setting time, degradation, mechanical property and ability to anti-washout. After addition 0 ∼ 25% α-CSH to the α-TCP cement with SFFs as curing liquid, it shortened the setting time of the modified composite to 10 ∼ 30 min. Furthermore, the addition of SFFs improved the compressive strength of the composite from 5.41 MPa to 9.44 MPa. The composites with both Na2HPO4 and SFFs as curing liquid showed good anti-collapse performance. The weight loss ratio of bone cement was −0.18 ∼ 12.08% in 4 weeks when the content of α-CSH in α-TCP/α-CSH was between 0 ∼ 25 wt%. During the degradation of α-CSH, the amorphous α-TCP were deposited as hydroxyapatite to formed a plate-like products on the surface of composite. Compared to the composite with Na2HPO4 solution as the curing liquid, alkaline phosphatase (ALP) activity of the composites using SFFs as curing liquid were maintained at high levels on the 14th day especially when the Ca/P ratio was 1.7. This study provides a theoretical basis for the regeneration of bone defects guided by bone cement materials.

Hydrogen peroxide (H2O2), as one of the most ubiquitous compounds, is widely used in many fields and performs important functions in physiological processes.

Recently, multifunctional nanoparticles have shown great prospects in cancer treatment, which have the ability to simultaneously deliver the drug, image and target tumor cells. In this paper, we designed a luminescent nanoparticles platform based on hydrothermal hyaluronic acid/amorphous calcium phosphate (HA-FCNs/ACP) with multifunctional properties for drug delivery, bio-imaging, and targeting treatment. HA-FCNs/ACP shows an ability to load curcumin (Cur) with pH-sensitive responsive drug release behavior and excellent biocompatibility. HA-FCNs/ACP dispersed in the cytoplasm through the overexpressed CD44 receptor that is actively targeted into human lung cancer cells (A549 cells). Meanwhile, the viability of A549 cells was significantly inhibited in vitro. The prepared HA-FCNs and HA-FCNs/ACP both exhibit excellent targeted bioimaging performance on cancer cells Hence, the as-prepared nanoparticles have promising applications in treating tumor disease.

Purpose To explore the mothers' caring experiences of children with congenital hand or foot abnormalities, and to inform the development of tailored intervention strategies to improve the mothers' well-being. Design and methods A qualitative study design was used. A purposive sample of 23 women whose children had congenital abnormalities of the hand or foot were enrolled. Semi-structured, in-depth interviews were conducted from December 2019 to May 2020. The Colaizzi's phenomenological approach was used for data analysis. Results Data analysis revealed four main themes: (a) dynamic negative affect; (b) low health literacy; (c) mothers' need for support; and (d) the shift in social activity and family role. Eleven subthemes were involved in these themes. Conclusions Women whose children have abnormal hands or feet have complicated care experiences and are under tremendous psychological pressure. Some mothers also encounter financial difficulties. Practice implications This study assessed the psychological impact on mothers of children with congenital hand or foot abnormalities. Our findings illustrate the needs of mothers, and call attention to this specific group. The findings may help inform healthcare and social interventions to facilitate the recovery of the affected children and cater to the needs of these families. Healthcare providers should provide adequate instructions to the parents regarding the provision of home management care following discharge from the hospital.

For decades, calcium phosphate bone cements (CPCs) showed impressive advantages for their good biocompatibility, injectability, and osteoconductivity in the bone repair field. However, it is still difficult to prepare CPCs with outstanding antibacterial and self-curing properties, sufficient phosphorus release, and osteoinductivity for clinical application. Herein, we used partially crystallized calcium phosphate and dicalcium phosphate anhydrate particles incorporated with black phosphorous nanosheets to prepare calcium phosphate bone cements (CPCs). The curing time, compressive strength, photothermal properties, and degradation performance of BP/CPC were investigated. In addition, the cytocompatibility and osteoinductivity of BP/CPC were evaluated by cell adhesion, cytotoxicity, alkaline phosphatase detection, alizarin red staining, and western blot assay. The results indicated that BP/CPC showed adjustable curing time, good cytocompatibility, outstanding photothermal properties, and osteoinductivity, suggesting their potential application for bone regeneration.

Hepatocellular carcinoma (HCC) is one of the deadliest tumors in the world with a high rate of recurrence and metastasis. Therefore, the most pressing issue today is the development of new drugs, diagnostic and therapeutic approaches for effective cancer treatment. Cancer stem cells (CSCs) play a pivotal role in tumor recurrence, tumor resistance, and tumor metastasis, which provides a new perspective on the development of liver cancer. In the study, a high-temperature thermal breakdown approach was used to create composite magnetic nanocubes modified by polyethyleneimine (PEI) and hyaluronic acid (HA). The Fe

Surface modification of nanoparticles with cellular protein components is a new biomimetic modification strategy, which utilizes the inherent affinity between homologous cells to introduce the same surface molecules into nanoparticles to improve the targeting performance. In this study, oleic acid (OA)-coated Fe3O4 nanocubes were prepared by a high-temperature thermal decomposition method and modified by 3, 4-dihydroxyphenylpropionic acid (DHCA); then, HeLa cell membranes were introduced onto the surface of the nanocubes through mixed coextrusion to try to endow them with the targeting function of natural cells. The results show that the prepared Fe3O4 nanocubes have high monodispersity, excellent water solubility, and biocompatibility. Moreover, the Fe3O4 nanocubes encapsulated by cellular protein show an obvious core-shell structure and the specific targeting property to HeLa cells is improved significantly, which is expected to be used in clinical targeted diagnosis and treatment of cancer.

Open bone fractures in clinical are not only difficult to heal but also at a high risk of infections. Annual cases of fractures which result from osteoporosis amount to approximately 9 million. The objective of this study is to load the antibiotic drug of vancomycin and tune its controlled delivery on a bone repair scaffold material of Mineralized Collagen/poly(lactic acid) (MCP)

This study aimed at designing a novel electrospun scaffolding material that structurally and chemically resembles native extracellular matrix for bone tissue engineering. Calcium chloride-complexed polyamide66 (PA66/CaCl

At present, the treatment of bone defect is one of the most concerned problems in biomedical fields. Despite the wide variety of scaffolds, there is a challenge to select materials that can mimic the structural integrity and biocompatibility of natural bone. In our study, gelatin methacryloyl (GelMA) and sodium alginate (Alg) were used to prepare three-dimensional (3D) GelMA/Alg hybrid hydrogel, which can simulate the structure and biological function of natural extracellular matrix due to their high water content and porous structure. The interconnected and homogeneous pores of the scaffold facilitate the transport of nutrients during the bone regeneration. Then hydroxyapatite (HA) coated GelMA/Alg (GelMA/Alg-HA) hydrogel was obtained by sequential mineralization. The mineralized hydrogel was obtained by immersing hydrogel alternately in a solution of calcium and phosphorus at 37 °C. The hydrogel was modified with a coating of HA under a mild condition. The calcium crosslinked Alg could provide nucleation sites for HA crystals. And the sequential mineralization will improve the physical properties and osteoinductivity of the hydrogels by introducing HA, which is similar to the mineral component of natural bone. Analytical results confirmed that the HA particles were uniformly distributed in the surface of the hydrogels and the mineral contents were about 40% after three cycles. The compressive strength was improved from 22.43 ± 6.39 to 131.03 ± 9.26 kPa. In addition, MC3T3-E1 cell co-culture experiments shown that the mineralized GelMA/Alg-HA hybrid hydrogel possess good biocompatibility, which is conducive to the growth of new bone tissue and bone repair.

Antibacterial composite nanofibers have recently been widely applied in biomedical fields. The purpose of this study is to combine Polyamide66 (PA) with carbon nanotubes (CNTs) and Ag nanoparticles through electrospinning and the aqueous reduction method to synthesis Ag@CNT/PA composite nanofibers with excellent conductivity, antibacterial property and cytocompatibility. The morphology and structure of Ag@CNT/PA composite nanofibers were analyzed by a series of characterizations. Conductivity of Ag@CNT/PA composite nanofibers in wet state was measured using a four-probe resistance tester. The antibacterial activity of Ag@CNT/PA composite nanofibers was tested by inhibition zone method, and the MG-63 cells were used to detect the cytotoxicological effects of the composite nanofibers. The results show that the Ag nanoparticles (50-100 nm) are distributed uniformly on the surface of nanofibers. Conductivity of Ag@CNT/PA composite nanofibers reaches (9.918 ± 0.043) × 10

Highly regular three-dimensional (3D) NiCo2O4/CoMoO4 hierarchical nanosheets (NSs) were prepared through a simple hydrothermal process. During the hydrothermal process, ethylamine solution is crucial for the morphology of NiCo2O4/CoMoO4 NSs and self-assembled formation of CoMoO4 with porous architecture on NiCo2O4. Such curly porous hierarchical structure with large surface areas is benefit to provide numerous accessible electrochemically active sites for faradaic redox reactions. In addition, the morphologies and the mass loading adjustment of NiCo2O4/CoMoO4 NSs can be easily achieved by controlling growth time. The as-prepared NiCo2O4/CoMoO4 electrode demonstrates superior specific capacitance (1730 F/g at 1 A/g), satisfied rate capability (60%, at 20 A/g), and excellent cycling stability (76.2% capacitance retention at 10 A/g). These good electrochemical performances exhibit that the as-obtained NiCo2O4/CoMoO4 composites are efficient electrode materials for pseudo-capacitors and may provide a useful guidance for obtaining electrode materials with outstanding electrochemical performance.

The lack of biological activity of pure titanium as a dental implant has attracted increasing attention. This condition can be improved by preparing a layer of nano-hydroxyapatite (nano-HA) coating that is stable and does not easily fall off, which however, remains a challenge. Here, we report the preparation of nano-HA crystals on calcified titanium oxide (TiO2) nanotube arrays by means of anodization, heat treatment, calcification in vacuum and hydrothermal phosphorylation, achieving the chemical bonding between the nano-HA coating and TiO2 substrate. The mechanism of coating formation was also investigated. The results confirmed that annealing at 450 °C could convert the amorphous nanotubes to the anatase structure. Calcium titanate (CaTiO3) was formed on the surface of nanotubes by heat treatment after calcification, which could provide nucleation sites for the formation of nano-HA. Needle-like nano-HA crystals were subsequently formed on the surface of the TiO2 nanotube arrays. The scratch test showed that the adhesion strength between the formed nano-HA coating and the TiO2 nanotube arrays was higher than 29.17 ± 1.07 N. In vitro cell proliferation and adhesion experiments showed that the nano-HA coating had good biocompatibility. Alkaline phosphatase (ALP) activity and osteocalcin (OCN) expressions highlighted the higher osteoconductivity of the nano-HA coating on the surface of TiO2 nanotube arrays compared to the pure Ti.

The development of high drug loading and sustained release nanoparticles by simple and economical methods is significant for the treatment of diseases. Amorphous calcium carbonate (ACC) is an ideal drug delivery system because of its excellent pH responsiveness, biocompatibility and biodegradability. In this work, ACC nanoparticles were successfully precipitated in ethanol–calcium solutions using ammonium carbonate as the internal source of CO2, which exhibited a relatively narrow size distribution in range of 10–200 nm. The microscopic morphology, amorphous characters, porous structure and thermal behavior of resultants were investigated by electron microscopy, Fourier-transform infrared spectroscopy, Brunauer–Emmett–Teller and thermogravimetric analysis, respectively. In vitro drug release assay showed that ACC nanoparticles had high loading capacity of curcumin (Cur) and favorable drug release properties. Furthermore, ACC-Cur showed excellent abilities to scavenge free radicals, protect Cur stability and damage A549 cells, providing a broadened space for the applications of this material in the fields of biomedical or food.

Surface modification of nanoparticles with cellular protein components is a new biomimetic modification strategy, which utilizes the inherent affinity between homologous cells to introduce the same surface molecules into nanoparticles to improve the targeting performance. In this study, oleic acid (OA)-coated Fe

In this study, a bioactive composite material based on calcium sulfate hemihydrate (CSH) bone cement was studied, which use calcium sulfate dihydrate (CSD) as coagulant and silk fibroin nanofibers (SFF) solution as the curing liquid, further loaded vancomycin silk fibroin microspheres (SFM/VCM). The drug release effect of bone cements caused by tuning weight content of SFM/VCM (0.5, 1, 2%) and the concentration of silk fibroin solution (SFS) (20, 60, 100 mg/mL) used for preparation of SFM was studied in this article. Scanning electron microscope (SEM) demonstrated that the average diameter of microspheres gradually increased and the setting time was prolonged with the concentration of SFS increasing. X-ray diffraction (XRD) and Fourier transform infrared (FTIR) were used to analyze the composition of composite materials. The result of compressive strength revealed that the composites contained 0.5% SFM/VCM showed better mechanical performance independent on the concentration of microspheres and the cumulative drug release percentage of all composites were less than 55% after 4 weeks. The drug-loading bone cement possesses not only injectability but also sustained release capability which has a promising prospect in the field of bone substitute material.

Phosphate-stabilized amorphous calcium carbonate (ACCP) has excellent biocompatibility, bioactivity, and biodegradability, and can be easily synthesized and stored. However, unmodified ACCP, as a controlled drug release carrier, decomposes rapidly in an acidic environment and highly depends on the system's pH value, which can not meet the need for long-term release of active substances, thus limiting its application scope. To realize the specific pH responsiveness of ACCP nanoparticles, we designed and synthesized monodisperse sodium alginate/ACCP (Alginate/ACCP) composite nanoparticles in this paper. After ultrasonic treatment, nanoparticles with an average particle size less than 200 nm could form stable water dispersion that could be dispersed for up to 10 d. Based on the specific pH sensitivity of sodium alginate, the drug-controlled release performance of composite nanoparticles and the therapeutic effect of drug-loaded nanoparticles on A549 cancer cells were studied. The results indicated that under the same pH condition, the curcumin (Cur) release rate of composite nanoparticles gradually decreased with sodium alginate addition. When the dosage of sodium alginate was 1.0 mg ml-1, the cumulative drug release rate of nanoparticles in 40 h was only about 35%. Besides, the drug-loaded nanoparticles showed the excellent killing ability of cancer cells, and the survival rate of cancer cells decreased in a concentration-dependent manner. Therefore, through reasonable optimization design, we can synthesize composite nanoparticles with excellent sustained-release properties to provide a new strategy for cancer cells' long-term treatment.

Inspired by the initial mineralization process in bone matrix vesicles (MVs), we used Dulbecco's Modified Eagle's Medium (DMEM) to establish the similar physiological environment to that in MVs for biomimetic mineralization on alginate (ALG) microspheres. The results showed that HA crystals were firstly formed and anchored on the membrane of microspheres like the initial deposition of hydroxyapatite crystals inside MVs. With the continuous growth and accumulation of mineral crystals, HA coating was finally formed on ALG microspheres. The mineralized ALG microspheres (M-ALG microspheres) show good biocompatibility and osteogenic performance. The HA coating is also conducive to the active migration of osteoblasts to the surface of M-ALG microspheres. Collectively, bone-like HA crystals anchored on ALG microspheres may provide a good prospect to promote the repair of bone defects.

Most existing hydrogel wound dressings lack gentle detachment property. In this work, novel hydrogels with anti-bacterial and induced detachment properties were prepared. Both gelatin (G) and sodium alginate (SA) are natural polymer materials. The G/SA hydrogels were prepared by dual cross-linking. The addition of SA significantly improves the mechanical properties of composite hydrogels. The tensile modulus and elongation at break of the G/SA hydrogels with 2.0% SA could reach 99.23 ± 2.18 kPa and 85.47 ± 5.01%, respectively. In addition, the interconnected porous network and high swelling ratio (over 9.99 ± 0.33) are beneficial to the transmission of oxygen and absorption of exudates to accelerate the healing of wound. Subsequently, berberine (BBR) was loaded into the G/SA hydrogels. The BBR/G/SA hydrogels show sustained drug release for 168 h and exhibit anti-bacterial effect against Staphylococcus aureus. The results of L929 cells cultured with the hydrogel extracts indicate good biocompatibility. Finally, results of EDTA-induced detachment performances demonstrate that the hydrogels could be removed from the wound as the internal structure destroyed. All illustrated results above demonstrated the BBR carried G/SA hydrogels have potential used as wound dressing materials in future.

Periodontal defect poses a significant challenge in orthopedics. Guided Bone Regeneration (GBR) membrane is considered as one of the most successful methods applied to reconstruct alveolar bone and then to achieve periodontal defect repair/regeneration. In this paper, a novel polyamide-6/chitosan@nano-hydroxyapatite/polyamide-6 (PA6/CS@n-HA/PA6) bilayered tissue guided membranes by combining a solvent casting and an electrospinning technique was designed. The developed PA6/CS@n-HA/PA6 composites were characterized by a series of tests. The results show that n-HA/PA6 and electrospun PA6/CS layers are tightly bound by molecular interaction and chemical bonding, which enhances the bonding strength between two distinct layers. The porosity and adsorption average pore diameter of the PA6/CS@n-HA/PA6 membranes are 36.90 % and 22.61 nm, respectively. The tensile strength and elastic modulus of PA6/CS@n-HA/PA6 composites are 1.41 ± 0.18 MPa and 7.15 ± 1.09 MPa, respectively. In vitro cell culture studies demonstrate that PA6/CS@n-HA/PA6 bilayered scaffolds have biological safety, good bioactivity, biocompatibility and osteoconductivity.

Using yeast as organic template and PDDA/PSS with opposite charge as polyelectrolyte, CaCO

In order to improve the osteogenic activity and mechanical strength of the guided bone regeneration (GBR) membrane for repairing bone defect, nano-hydroxyapatite/chitosan (nHA/CS) composite microspheres were prepared through in situ biomimetic method, then composite microspheres were incorporated into CS membrane. The morphologies and mechanical properties of the composite membranes were investigated through scanning electronic microscopy (SEM) and universal mechanical testing machine. The results show that the in situ biomimetic nHA/CS microspheres were embedded in CS membrane and were integrated tightly with CS matrix. The mechanical properties of GBR membranes containing in situ nHA/CS microspheres is significantly higher than that of membranes containing pure CS microspheres and blending nHA/CS microspheres. Its elongation rate at break reaches 5.61 ± 0.95%. The elastic modulus and strength of the GBR membranes can reach 766.27 ± 20.68 and 43.32 ± 0.95 MPa, respectively. Further, The work-of-fracture of the membranes with in situ microspheres approaches 2.71 ± 0.25 J/m2, which is about 3 times of the pure CS membrane. The cell culture results display that the GBR membranes containing in situ biomimetic nHA/CS microspheres exhibit good cytocompatibility.