-
Scientific Reports May 2024Bone graft granules implanted in bone defects come into physical contact with the host bone and form interconnected porous structure. However, there exists an accidental...
Bone graft granules implanted in bone defects come into physical contact with the host bone and form interconnected porous structure. However, there exists an accidental displacement of granules to unintended locations and leakage of granules from bone defects. Although covering the defect with a barrier membrane prevents granule emanation, this procedure is troublesome. To resolve these problems, we fabricated bioresorbable mesh cages (BRMc) in this study. Bone graft granules composed of carbonate apatite alone (Gr) and bioresorbable mesh cages (BRMc/Gr) introduced the bone graft granules and were implanted into the bone defect in the rabbit femur. Micro-computed tomography and histological analysis were conducted at 4 and 12 weeks after implantation. Osteoprogenitors in the bloodstream from the host bone passed through the pores of BRMc, penetrated the porous structure of graft granules, and might interact with individual granules. Then bone remodeling could progress actively and new bone was formed. The new bone formation was similar to the host bone at 12 weeks and there were minimal signs of local tissue inflammation. BRMc/Gr could reduce the risk of unwanted new bone formation occurring due to loss of granules from the bone defects compared with Gr because BRMc enclosed granules and prevent granules leakage from bone defects and BRMc could not induce unfavorable effects to forme new bone. Additionally, BRMc/Gr could keep granules assembled in one place, avoid displacement of granules to unintended locations, and carry easily. These results demonstrated that BRMc/Gr was effective in bone regeneration and improved clinical handling.
Topics: Animals; Rabbits; Femur; Bone Transplantation; X-Ray Microtomography; Absorbable Implants; Bone Regeneration; Osteogenesis
PubMed: 38816454
DOI: 10.1038/s41598-024-63067-y -
Scientific Reports May 2024This study introduces microbiologically induced calcium phosphate precipitation (MICPP) as a novel and environmentally sustainable method of soil stabilization. Using...
This study introduces microbiologically induced calcium phosphate precipitation (MICPP) as a novel and environmentally sustainable method of soil stabilization. Using Limosilactobacillus sp., especially NBRC 14511 and fish bone solution (FBS) extracted from Tuna fish bones, the study was aimed at testing the feasibility of calcium phosphate compounds (CPCs) deposition and sand stabilization. Dynamic changes in pH and calcium ion (Ca) concentration during the precipitation experiments affected the precipitation and sequential conversion of dicalcium phosphate dihydrate (DCPD) to hydroxyapatite (HAp), which was confirmed by XRD and SEM analysis. Sand solidification experiments demonstrated improvements in unconfined compressive strength (UCS), especially at higher Urea/Ca ratios. The UCS values obtained were 10.35 MPa at a ratio of 2.0, 3.34 MPa at a ratio of 1.0, and 0.43 MPa at a ratio of 0.5, highlighting the advantages of MICPP over traditional methods. Microstructural analysis further clarified the mineral composition, demonstrating the potential of MICPP in environmentally friendly soil engineering. The study highlights the promise of MICPP for sustainable soil stabilization, offering improved mechanical properties and reducing environmental impact, paving the way for novel geotechnical practices.
Topics: Calcium Phosphates; Sand; Chemical Precipitation; Animals; Hydrogen-Ion Concentration; Durapatite; Soil; Compressive Strength; X-Ray Diffraction
PubMed: 38816387
DOI: 10.1038/s41598-024-63016-9 -
Scientific Reports May 2024Calcification of aortic valve leaflets is a growing mortality threat for the 18 million human lives claimed globally each year by heart disease. Extensive research has...
Calcification of aortic valve leaflets is a growing mortality threat for the 18 million human lives claimed globally each year by heart disease. Extensive research has focused on the cellular and molecular pathophysiology associated with calcification, yet the detailed composition, structure, distribution and etiological history of mineral deposition remains unknown. Here transdisciplinary geology, biology and medicine (GeoBioMed) approaches prove that leaflet calcification is driven by amorphous calcium phosphate (ACP), ACP at the threshold of transformation toward hydroxyapatite (HAP) and cholesterol biomineralization. A paragenetic sequence of events is observed that includes: (1) original formation of unaltered leaflet tissues: (2) individual and coalescing 100's nm- to 1 μm-scale ACP spherules and cholesterol crystals biomineralizing collagen fibers and smooth muscle cell myofilaments; (3) osteopontin coatings that stabilize ACP and collagen containment of nodules preventing exposure to the solution chemistry and water content of pumping blood, which combine to slow transformation to HAP; (4) mm-scale nodule growth via ACP spherule coalescence, diagenetic incorporation of altered collagen and aggregation with other ACP nodules; and (5) leaflet diastole and systole flexure causing nodules to twist, fold their encasing collagen fibers and increase stiffness. These in vivo mechanisms combine to slow leaflet calcification and establish previously unexplored hypotheses for testing novel drug therapies and clinical interventions as viable alternatives to current reliance on surgical/percutaneous valve implants.
Topics: Calcium Phosphates; Humans; Aortic Valve; Osteopontin; Calcinosis; Collagen; Durapatite; Aortic Valve Stenosis; Cholesterol
PubMed: 38806601
DOI: 10.1038/s41598-024-62962-8 -
International Journal of Nanomedicine 2024There is an ongoing need for improved healing response and expedited osseointegration on the Ti implants in acetabular fracture sites. To achieve adequate bonding and...
INTRODUCTION
There is an ongoing need for improved healing response and expedited osseointegration on the Ti implants in acetabular fracture sites. To achieve adequate bonding and mechanical stability between the implant surface and the acetabular fracture, a new coating technology must be developed to promote bone integration and prevent bacterial growth.
METHODS
A cylindrical Ti substrate mounted on a rotating specimen holder was used to implant Ca, P, and Sr ions at energies of 100 KeV, 75 KeV and 180 KeV, respectively, using a low-energy accelerator to synthesize strontium-substituted hydroxyapatite at varying conditions. Ag ions of energy 100 KeV were subsequently implanted on the as-formed surface at the near-surface region to provide anti-bacterial properties to the as-formed specimen.
RESULTS
The properties of the as-formed ion-implanted specimen were compared with the SrHA-Ag synthesized specimens by cathodic deposition and low-temperature high-speed collision technique. The adhesion strength of the ion-implanted specimen was 43 ± 2.3 MPa, which is well above the ASTM standard for Ca-P coating on Ti. Live/dead cell analysis showed higher osteoblast activity on the ion-implanted specimen than the other two. Ag in the SrHA implanted Ti by ion implantation process showed superior antibacterial activity.
DISCUSSION
In the ion implantation technique, nano-topography patterned surfaces are not concealed after implantation, and their efficacy in interacting with the osteoblasts is retained. Although all three studies examined the antibacterial effects of Ag ions and the ability to promote bone tissue formation by MC3T3-E1 cells on SrHA-Ag/Ti surfaces, ion implantation techniques demonstrated superior ability. The synthesized specimen can be used as an effective implant in acetabular fracture sites based on their mechanical and biological properties.
Topics: Titanium; Silver; Strontium; Anti-Bacterial Agents; Acetabulum; Animals; Coated Materials, Biocompatible; Osseointegration; Mice; Surface Properties; Fractures, Bone; Durapatite; Osteoblasts; Hydroxyapatites; Prostheses and Implants; Ions; Humans; Cell Line
PubMed: 38803996
DOI: 10.2147/IJN.S464905 -
Scientific Reports May 2024Copper mineralization in the Pulang (PL) porphyry deposit, Langdu (LD) porphyry-skarn deposit and Songnuo (SN) porphyry prospect in northwestern Yunnan, China, is...
Copper mineralization in the Pulang (PL) porphyry deposit, Langdu (LD) porphyry-skarn deposit and Songnuo (SN) porphyry prospect in northwestern Yunnan, China, is closely related to the emplacement of quartz monzonite porphyries. The chemical compositions of biotite and apatite from those porphyries were analyzed to calculate the halogen fugacity and to constrain mineralized and barren porphyries. Our data show that biotites from the PL deposit have higher MgO, SiO, TiO and F contents than those from the LD deposit or SN prospect. Compared to those in the LD deposit and SN prospect, the Mg (atoms per formula unit (apfu)) and Al (apfu) value in biotite is greater, and the F content is greater and the SO and CeO/YO ratio in apatite are lower in the PL deposit. Ti-biotite thermometry and apatite-biotite geothermometry show that the crystallization temperature of biotite from the PL deposit is higher than that from the SN prospect or LD deposit. The results suggest that oxygen fugacity, magmatic sulfur, and HO contents cannot be used to efficiently distinguish the PL deposit from the LD deposit and SN prospect. However, the halogen chemistry of biotite from the PL deposit is distinctly different from that of the LD deposit or SN prospect according to the lower IV (F), indicating that mineralized quartz monzonite porphyries in the PL deposit formed during the late magmatic stage, which is in contrast to those in the LD deposit and SN prospect. The mineralized porphyries display a remarkable negative linear relationship (r = - 0.96) with the log (f HF/f HCl) and log (f HO/f HF) ratio, which can be used to distinguish the mineralized and barren porphyries. Compared with other typical porphyry Cu systems, there is a remarkable positive linear relationship between IV (Cl) and log (f HO/f HCl). In addition, the linear slope and intercept for log (f HO/f HCl) ratios and the IV (Cl) of biotite from the potassic and phyllic alteration zones are significantly greater than those from other porphyries.
PubMed: 38802473
DOI: 10.1038/s41598-024-62120-0 -
RSC Advances May 2024Prismatic crystals of partially potassium substituted lead fluorapatite PbCaK(PO)F were grown through a solid-state reaction. The structural study conducted by...
Prismatic crystals of partially potassium substituted lead fluorapatite PbCaK(PO)F were grown through a solid-state reaction. The structural study conducted by single-crystal X-ray diffraction revealed that the compound crystallizes in the hexagonal 6/ space group, with unit cell parameters = = 9.7190(5) Å, = 7.1700(6) Å and = 587.37(7) Å( = 1), as well as final values amounting to and w of 0.0309 and 0.0546, respectively. The structural refinement demonstrated that Pb occupies both the (6 and (4) structural sites of hexagonal fluorapatite, K occupies the (6) site, and Ca is placed on the (4) site. Powder X-ray diffraction study indicated the absence of additional phases or impurities. Chemical analysis using atomic absorption spectrometry and energy-dispersive X-ray spectroscopy confirmed the expected chemical formula. The electrical conductivity measured over a wide temperature range was found to be governed by the ion mobility mechanism in the tunnel along the axis (probably attributed to the fluorine ion located there). We, therefore, could infer from the analysis of the complex impedance spectra that the electrical conductivity of our apatite depends essentially on the temperature and frequency, which produces a relaxation phenomenon and semiconductor-like behavior. Moreover, the strong absorption in the UV-Visible region was substantiated through studies of the optical properties of the developed sample. Fluorescence spectra exhibited emissions in the orange regions when excited at 375 nm. The findings of the phenomena resulting from the emission and conduction of the apatite in question suggest its potential for application in various technological fields such as photovoltaic cells, optoelectronics, photonics, LED applications, catalysis and batteries.
PubMed: 38799221
DOI: 10.1039/d4ra01014k -
ZIF-8@Hydroxyapatite Composite as a High Potential Material for Prolonged Delivery of Agrochemicals.ACS Applied Materials & Interfaces Jun 2024Although agrochemical practices can enhance agricultural productivity, their intensive application has resulted in the deterioration of ecosystems. Therefore, it is...
Although agrochemical practices can enhance agricultural productivity, their intensive application has resulted in the deterioration of ecosystems. Therefore, it is necessary to develop more efficient and less toxic methods against pests and infections while improving crop productivity. Moving toward sustainable development, in this work, we originally described the preparation of a composite (ZIF-8@HA) consisting of the coating of zeolitic-like metal-organic framework (MOF) ZIF-8 (based on Zn, an essential micronutrient in plants with antibacterial, antifungal, and antifouling properties) with hydroxyapatite (HA) nanoparticles (i.e., nanofertilizer). The interaction between the HA and ZIF-8 has been characterized through a combination of techniques, such as microscopic techniques, where the presence of a HA coating is demonstrated; or by analysis of the surface charge with a dramatic change in the Z-potential (from +18.7 ± 0.8 to -27.6 ± 0.7 mV for ZIF-8 and ZIF-8@HA, respectively). Interestingly, the interaction of HA with ZIF-8 delays the MOF degradation (from 4 h for pristine ZIF-8 to 168 h for HA-coated material), providing a slower and gradual release of zinc. After a comprehensive characterization, the potential combined fertilizer and bactericidal effect of ZIF-8@HA was investigated in wheat () seeds and (). ZIF-8@HA (7.3 ppm) demonstrated a great fertilizer effect, increasing shoot (9.4 %) and root length (27.1 %) of wheat seeds after 11 days at 25 °C under dark conditions, improving the results obtained with HA, ZIF-8, or ZnSO or even physically mixed constituents (HA + ZIF-8). It was also effective in the growth inhibition (>80 % of growth inhibition) of , a vegetal pathogen causing considerable crop decline. Therefore, this work demonstrates the potential of MOF@HA composites and paves the way as a promising agrochemical with improved fertilizer and antibacterial properties.
Topics: Durapatite; Metal-Organic Frameworks; Agrochemicals; Anti-Bacterial Agents; Nanoparticles; Zeolites; Triticum; Imidazoles
PubMed: 38798175
DOI: 10.1021/acsami.4c06016 -
International Journal of Biological... Jun 2024There is a growing demand for engineered bone tissues custom-designed to match the patient-specific defect size and in vitro models for studying bone diseases and/or...
There is a growing demand for engineered bone tissues custom-designed to match the patient-specific defect size and in vitro models for studying bone diseases and/or drug screening. Herein, we propose a bioprinted bone tissue construct using SaOs-2 cells within alginate/gellan gum/hydroxyapatite inks. Different ink formulations were developed with varying hydroxyapatite content and then evaluated for viscoelasticity, printability, biomineralization properties, post-printing viability, proliferation, metabolic activity, and osteogenic phenotype of SaOs-2-encapsulated cells. Results indicate that ink formulations exhibit non-Newtonian shear-thinning behaviour, maintaining shape integrity and structural stability post-printing. Ink mineralization rates increase with the hydroxyapatite content, rendering them suitable for bone defect strategies. Post-printed cells in the developed constructs remain live, spreading, and metabolically active but do not proliferate. Osteogenic gene and protein expression, both early and late, show upregulation at day 7 relative to day 1, followed by downregulation at day 14. Lower hydroxyapatite content inks demonstrate up to fourfold upregulation in genes and proteins at most time points. Additionally, these constructs release calcium and phosphate at levels conducive to mineralization. Overall, the tissue-engineered miniaturized constructs not only meet the criteria for early-stage bone defect/fracture regeneration but also serve as a promising platform for drug screening and evaluating potential therapeutic treatments.
Topics: Durapatite; Alginates; Bioprinting; Humans; Osteogenesis; Ink; Polysaccharides, Bacterial; Bone Regeneration; Tissue Scaffolds; Tissue Engineering; Bone and Bones; Cell Proliferation; Cell Survival
PubMed: 38797304
DOI: 10.1016/j.ijbiomac.2024.132611 -
ACS Applied Materials & Interfaces Jun 2024The application of hydroxyapatite (HA)-based templates is quite often seen in bone tissue engineering since that HA is an osteoconductive bioceramic material, which...
The application of hydroxyapatite (HA)-based templates is quite often seen in bone tissue engineering since that HA is an osteoconductive bioceramic material, which mimics the inorganic component of mineralized tissues. However, the reported osteoconductivity varies in vitro and in vivo, and the levels of calcium (Ca) release most favorable to osteoconduction have yet to be determined. In this study, HA-based templates were fabricated by melt-extrusion 3D-printing and characterized in order to determine a possible correlation between Ca release and osteoconduction. The HA-based templates were blended with poly(lactide--trimethylene carbonate) (PLATMC) at three different HA ratios: 10, 30, and 50%. The printability and physical properties of the HA templates were compared with those of pristine PLATMC. In vitro, osteoconductivity was assessed using seeded human bone marrow-derived mesenchymal stem cells. A mild rate of Ca release was observed for HA10 templates, which exhibited higher mineralized extracellular matrix (ECM) secretion than PLATMC at 14 and 21 days. In contrast, the high rate of Ca release exhibited by HA30 and HA50 templates was associated with reduced osteoconduction and impeded mineralized ECM secretion in vitro. Similar results were observed in vivo. In the calvarial defect model in rabbit, PLATMC and HA10 templates exhibited the highest amount of new bone formation, with obvious contact osteogenesis on their surfaces. In contrast, HA30 and HA50 exhibited distant osteogenesis and reduced amounts of new bone ingrowth. It is concluded that HA-based templates are osteoconductive only at low rates of Ca release.
Topics: Printing, Three-Dimensional; Durapatite; Animals; Calcium; Rabbits; Humans; Mesenchymal Stem Cells; Bone Regeneration; Tissue Engineering; Tissue Scaffolds; Osteogenesis
PubMed: 38795033
DOI: 10.1021/acsami.4c01472 -
Polymers May 2024There is an essential clinical need to develop rapid process scaffolds to repair bone defects. The current research presented the development of calcium zirconium...
There is an essential clinical need to develop rapid process scaffolds to repair bone defects. The current research presented the development of calcium zirconium silicate/polycaprolactone for bone tissue engineering utilising melt extrusion-based 3D printing. Calcium zirconium silicate (CZS) nanoparticles were added to polycaprolactone (PCL) porous scaffolds to enhance their biological and mechanical properties, while the resulting properties were studied extensively. No significant difference was found in the melting point of the samples, while the crystallisation temperature points of the samples containing bioceramic increased from 36.1 to 40.2 °C. Thermal degradation commenced around 350 °C for all materials. According to our results, increasing the CZS content from 0 to 40 wt.% (PC40) in porous scaffolds (porosity about 55-62%) improved the compressive strength from 2.8 to 10.9 MPa. Furthermore, apatite formation ability in SBF solution increased significantly by enhancing the CZS percentage. According to MTT test results, the viability of MG63 cells improved remarkably (~29%) in PC40 compared to pure PCL. These findings suggest that a 3D-printed PCL/CZS composite scaffold can be fabricated successfully and shows great potential as an implantable material for bone tissue engineering applications.
PubMed: 38794582
DOI: 10.3390/polym16101389