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Biotechnology and Bioengineering Jun 2024Injectable, tissue mimetic, bioactive, and biodegradable hydrogels offer less invasive regeneration and repair of tissues. The monitoring swelling and in vitro...
Injectable, tissue mimetic, bioactive, and biodegradable hydrogels offer less invasive regeneration and repair of tissues. The monitoring swelling and in vitro degradation capacities of hydrogels are highly important for drug delivery and tissue regeneration processes. Bioactivity of bone tissue engineered constructs in terms of mineralized apatite formation capacity is also pivotal. We have previously reported in situ forming chitosan-based injectable hydrogels integrated with hydroxyapatite and heparin for bone regeneration, promoting angiogenesis. These hydrogels were functionalized by glycerol and pH to improve their mechano-structural properties. In the present study, functionalized hybrid hydrogels were investigated for their swelling, in vitro degradation, and bioactivity performances. Hydrogels have degraded gradually in phosphate-buffered saline (PBS) with and without lysozyme enzyme. The percentage weight loss of hydrogels and their morphological and chemical properties, and pH of media were analyzed. The swelling ratio of hydrogels (55%-68%(wt), 6 h of equilibrium) indicated a high degree of cross-linking, can be suitable for controlled drug release. Hydrogels have gradually degraded reaching to 60%-70% (wt%) in 42 days in the presence and absence of lysozyme, respectively. Simulated body fluid (SBF)-treated hydrogels containing hydroxyapatite-induced needle-like carbonated-apatite mineralization was further enhanced by heparin content significantly.
PubMed: 38837342
DOI: 10.1002/bit.28755 -
Current Protocols Jun 2024Adeno-associated virus (AAV) vectors can efficiently transduce exogenous genes into various tissues in vivo. Owing to their convenience, high efficiency, long-term...
Adeno-associated virus (AAV) vectors can efficiently transduce exogenous genes into various tissues in vivo. Owing to their convenience, high efficiency, long-term stable gene expression, and minimal side effects, AAV vectors have become one of the gold standards for investigating gene functions in vivo, especially in non-clinical studies. However, challenges persist in efficiently preparing a substantial quantity of high-quality AAV vectors. Commercial AAV vectors are typically associated with high costs. Further, in-laboratory production is hindered by the lack of specific laboratory equipment, such as ultracentrifuges. Therefore, a simple, quick, and scalable preparation method for AAV vectors is needed for proof-of-concept experiments. Herein, we present an optimized method for producing and purifying high-quality AAV serotype 9 (AAV9) vectors using standard laboratory equipment and chromatography. Using ceramic hydroxyapatite as a mixed-mode chromatography medium can markedly increase the quality of purified AAV vectors. Basic Protocols and optional methods for evaluating purified AAV vectors are also described. © 2024 The Author(s). Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Production of AAV9 vectors in 293EB cells Basic Protocol 2: Concentration and buffer exchange of AAV9 vectors from 293EB cell culture supernatants using tangential flow filtration Basic Protocol 3: Purification of AAV9 vectors from TFF samples using ceramic hydroxyapatite chromatography Basic Protocol 4: Analysis of the purified AAV9 vectors.
Topics: Dependovirus; Genetic Vectors; Humans; Ceramics; Serogroup; Durapatite; Chromatography; HEK293 Cells
PubMed: 38837274
DOI: 10.1002/cpz1.1068 -
Biointerphases May 2024Titanium (Ti) is widely utilized as an implant material; nonetheless, its integration with bone tissue faces limitations due to a patient's comorbidities. To address...
Titanium (Ti) is widely utilized as an implant material; nonetheless, its integration with bone tissue faces limitations due to a patient's comorbidities. To address this challenge, we employed a strategic approach involving the growth of thin films by spin-coating and surface functionalization with etidronate (ETI), alendronate (ALE), and risedronate (RIS). Our methodology involved coating of Ti cp IV disks with thin films of TiO2, hydroxyapatite (HA), and their combinations (1:1 and 1:2 v/v), followed by surface functionalization with ETI, ALE, and RIS. Bisphosphonate-doped films were evaluated in terms of surface morphology and physical-chemical properties by techniques such as electron microscopy, confocal microscopy, and x-ray photoelectron spectroscopy. The antibacterial potential of bisphosphonates alone or functionalized onto the Ti surface was tested against Staphylococcus aureus biofilms. Primary human bone mesenchymal stem cells were used to determine in vitro cell metabolism and mineralization. Although RIS alone did not demonstrate any antibacterial effect as verified by minimum inhibitory concentration assay, when Ti surfaces were functionalized with RIS, partial inhibition of Staphylococcus aureus growth was noted, probably because of the physical-chemical surface properties. Furthermore, samples comprising TiO2/HA (1:1 and 1:2 v/v) showcased an enhancement in the metabolism of nondifferentiated cells and can potentially enhance the differentiation of osteoblastic precursors. All samples demonstrated cell viability higher than 80%. Addition of hydroxyapatite and presence of bisphosphonates increase the metabolic activity and the mineralization of human bone mesenchymal cells. While these findings hold promise, it is necessary to conduct further studies to evaluate the system's performance in vivo and ensure its long-term safety. This research marks a significant stride toward optimizing the efficacy of titanium implants through tailored surface modifications.
Topics: Titanium; Humans; Anti-Bacterial Agents; Staphylococcus aureus; Diphosphonates; Microbial Sensitivity Tests; Mesenchymal Stem Cells; Surface Properties; Biofilms; Coated Materials, Biocompatible; Cells, Cultured; Durapatite
PubMed: 38836787
DOI: 10.1116/6.0003611 -
Cellular and Molecular Biology... Jun 2024Epigenetic change has been found to play an important role in cell differentiation and regulation and the dental pulp stem cell in tissue engineering is gaining...
Epigenetic change has been found to play an important role in cell differentiation and regulation and the dental pulp stem cell in tissue engineering is gaining attention due to the ability of cells to differentiate into odontoblast and other cells. This study evaluated the influence of poly L- lactic acid with hydroxyapatite-coated with polyaniline scaffold (PLLA/HA/PANI) on dental pulp stem cell (DPSC) proliferation and differentiation. After scaffold preparation and DPSCs seeding, the cells proliferation and differentiation were evaluated by immunocytochemistry assay and cell viability was measured by cytotoxicity / MTT assay. The results showed (PLLA/HA/PANI) scaffold facilitates DPSC proliferation and differentiation with gene expression. This finding underscores the promise of this biomaterial combination as a scaffold for dental tissue regeneration and application.
Topics: Dental Pulp; Humans; Cell Differentiation; Odontoblasts; Tissue Scaffolds; Stem Cells; Osteoblasts; Cell Proliferation; Biocompatible Materials; Durapatite; Aniline Compounds; Polyesters; Cell Survival; Cells, Cultured; Tissue Engineering
PubMed: 38836669
DOI: 10.14715/cmb/2024.70.6.21 -
Injury Jul 2024As a two-stage surgical procedure, Masquelet's technique has been used to care for critical-size bone defects (CSD). We aimed to determine the effects of modified and...
BACKGROUND
As a two-stage surgical procedure, Masquelet's technique has been used to care for critical-size bone defects (CSD). We aimed to determine the effects of modified and altered bone cement with biological or chemical enriching agents on the progression of Masquelet's induced membrane (IM) applied to a rat femur CSD model, and to compare the histopathological, biochemical, and immunohistochemical findings of these cements to enhance IM capacity.
METHODS
Thirty-five male rats were included in five groups: plain polymethyl methacrylate (PMMA), estrogen-impregnated PMMA (E+PMMA), bone chip added PMMA (BC+PMMA), hydroxyapatite-coated PMMA (HA) and calcium phosphate cement (CPC). The levels of bone alkaline phosphatase (BALP), osteocalcin (OC), and tumor necrosis factor-alpha (TNF-α) were analyzed in intracardiac blood samples collected at the end of 4 weeks of the right femur CSD intervention. All IMs collected were fixed and prepared for histopathological scoring. The tissue levels of rat-specific Transforming Growth Factor-Beta (TGF-β), Runt-related Transcription Factor 2 (Runx2), and Vascular Endothelial Growth Factor (VEGF) were analyzed immunohistochemically.
RESULTS
Serum levels of BALP and OC were significantly higher in E+PMMA and BC+PMMA groups than those of other groups (P = 0.0061 and 0.0019, respectively). In contrast, TNF-α levels of all groups with alternative bone cement significantly decreased compared to bare PMMA (P = 0.0116). Histopathological scores of E+PMMA, BC+PMMA, and CPC groups were 6.86 ± 1.57, 4.71 ± 0.76, and 6.57 ± 1.51, respectively, which were considerably higher than those of PMMA and HA groups (3.14 ± 0.70 and 1.86 ± 0.69, respectively) (P < 0.0001). Significant increases in TGF-β and VEGF expressions were observed in E+PMMA and CPC groups (P = 0.0001 and <0.0001, respectively) whereas Runx2 expression significantly increased only in the HA group compared to other groups (P < 0.0001).
CONCLUSIONS
The modified PMMA with E and BC, and CPC as an alternative spacer resulted in a well-differentiated IM and increased IM progression by elevating BALP and OC levels in serum and by mediating expressions of TGF-β and VEGF at the tissue level. Estrogen-supplemented cement spacer has yielded promising findings between modified and alternative bone cement.
Topics: Animals; Bone Cements; Rats; Male; Polymethyl Methacrylate; Disease Models, Animal; Vascular Endothelial Growth Factor A; Femur; Femoral Fractures; Core Binding Factor Alpha 1 Subunit; Osteocalcin; Alkaline Phosphatase; Transforming Growth Factor beta; Tumor Necrosis Factor-alpha; Rats, Sprague-Dawley; Calcium Phosphates; Fracture Healing; Bone Regeneration; Durapatite
PubMed: 38834011
DOI: 10.1016/j.injury.2024.111627 -
Micron (Oxford, England : 1993) Sep 2024The silver/magnesium doped hydroxyapatite (AgMgHAp, CaAgMg(PO)(OH), x=0.05 and y=0.02) nanocomposites coatings were deposited on Si substrate using the dip coating...
The silver/magnesium doped hydroxyapatite (AgMgHAp, CaAgMg(PO)(OH), x=0.05 and y=0.02) nanocomposites coatings were deposited on Si substrate using the dip coating technique. The resulting coatings were characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), Fourier transform infrared (FTIR-ATR) spectroscopy, atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). The EDS analysis highlighted the presence of the constitutive elements of the silver/magnesium doped hydroxyapatite (AgMgHAp) nanocomposites coatings. The surface microtexture of the AgMgHAp was assessed by atomic force microscopy (AFM) technique. The AFM data suggested the obtaining of a uniform deposited layer comprised of equally distributed nanoconglomerates. FT-IR studies highlighted the presence of vibrational modes associated with the phosphate and hydroxyl groups. No bands associated with silver or magnesium were observed. The XPS analysis highlighted the presence of the constituent elements of hydroxyapatite (Ca 2p, P 2 s, O 1 s), as well as dopants (Ag 3d, Mg 1 s and Mg 2p). The antifungal evaluation of AgMgHAp coatings was carried out using the Candida albicans ATCC 10231 fungal strain. The results of the antifungal assay revealed that the AgMgHAp coatings exhibited a strong inhibitory antifungal activity. Furthermore, the data highlighted that the AgMgHAp inhibited the development of biofilm on their surface. The results revealed that the antifungal activity of the coating varied based on the duration of incubation. On the other hand, the data also showed that AgMgHAp nanocomposites coatings inhibited the fungal cell adhesion and development from the early stages of the incubation. In addition to morphological analysis, we additionally take advantage of AFM images to investigate and explore the domain of fractal and multifractal analysis applied to the films under evaluation. Our studies indicates that nanocomposite coatings made from AgMgHAp demonstrate strong antifungal properties. Our studies indicates that nanocomposite coatings made from AgMgHAp demonstrate strong antifungal properties. These results suggest the potential of AgMgHAp nanocomposite coatings as a promising solution for developing innovative antifungal devices in biomedical applications.
Topics: Durapatite; Antifungal Agents; Silver; Nanocomposites; Magnesium; Spectroscopy, Fourier Transform Infrared; Microscopy, Atomic Force; Candida albicans; Microscopy, Electron, Scanning; Photoelectron Spectroscopy; Microbial Sensitivity Tests; Spectrometry, X-Ray Emission; Coated Materials, Biocompatible; Surface Properties
PubMed: 38833994
DOI: 10.1016/j.micron.2024.103661 -
Scientific Reports Jun 2024Surface structure plays a crucial role in determining cell behavior on biomaterials, influencing cell adhesion, proliferation, differentiation, as well as immune cells...
Surface structure plays a crucial role in determining cell behavior on biomaterials, influencing cell adhesion, proliferation, differentiation, as well as immune cells and macrophage polarization. While grooves and ridges stimulate M2 polarization and pits and bumps promote M1 polarization, these structures do not accurately mimic the real bone surface. Consequently, the impact of mimicking bone surface topography on macrophage polarization remains unknown. Understanding the synergistic sequential roles of M1 and M2 macrophages in osteoimmunomodulation is crucial for effective bone tissue engineering. Thus, exploring the impact of bone surface microstructure mimicking biomaterials on macrophage polarization is critical. In this study, we aimed to sequentially activate M1 and M2 macrophages using Poly-L-Lactic acid (PLA) membranes with bone surface topographical features mimicked through the soft lithography technique. To mimic the bone surface topography, a bovine femur was used as a model surface, and the membranes were further modified with collagen type-I and hydroxyapatite to mimic the bone surface microenvironment. To determine the effect of these biomaterials on macrophage polarization, we conducted experimental analysis that contained estimating cytokine release profiles and characterizing cell morphology. Our results demonstrated the potential of the hydroxyapatite-deposited bone surface-mimicked PLA membranes to trigger sequential and synergistic M1 and M2 macrophage polarizations, suggesting their ability to achieve osteoimmunomodulatory macrophage polarization for bone tissue engineering applications. Although further experimental studies are required to completely investigate the osteoimmunomodulatory effects of these biomaterials, our results provide valuable insights into the potential advantages of biomaterials that mimic the complex microenvironment of bone surfaces.
Topics: Animals; Macrophages; Surface Properties; Cattle; Polyesters; Mice; Biocompatible Materials; Tissue Engineering; Durapatite; Cytokines; Bone and Bones; Cell Differentiation; Macrophage Activation; Cell Adhesion; RAW 264.7 Cells; Cell Polarity; Femur; Collagen Type I
PubMed: 38830871
DOI: 10.1038/s41598-024-62484-3 -
Chemosphere Aug 2024The catalytic performance of modified hydroxyapatite nanoparticles, CaFeW(PO)(OH), was applied for the degradation of methylene blue (MB), fast green FCF (FG) and...
Monitoring Photo-Fenton and Photo-Electro-Fenton process of contaminants emerging concern by a gas diffusion electrode using CaFeW(PO)(OH) nanoparticles as heterogeneous catalyst.
The catalytic performance of modified hydroxyapatite nanoparticles, CaFeW(PO)(OH), was applied for the degradation of methylene blue (MB), fast green FCF (FG) and norfloxacin (NOR). XPS analysis pointed to the successful partial replacement of Ca by Fe. Under photo-electro-Fenton process, the catalyst CaFeWFe(PO)(OH) was combined with UVC radiation and electrogenerated HO in a Printex L6 carbon-based gas diffusion electrode. The application of only 10 mA cm resulted in 100% discoloration of MB and FG dyes in 50 min of treatment at pH 2.5, 7.0 and 9.0. The proposed treatment mechanism yielded maximum TOC removal of ∼80% and high mineralization current efficiency of ∼64%. Complete degradation of NOR was obtained in 40 min, and high mineralization of ∼86% was recorded after 240 min of treatment. Responses obtained from LC-ESI-MS/MS are in line with the theoretical Fukui indices and the ECOSAR data. The study enabled us to predict the main degradation route and the acute and chronic toxicity of the by-products formed during the contaminants degradation.
Topics: Catalysis; Hydrogen Peroxide; Iron; Electrodes; Methylene Blue; Nanoparticles; Water Pollutants, Chemical; Norfloxacin; Durapatite; Coloring Agents; Photochemical Processes; Ultraviolet Rays
PubMed: 38830460
DOI: 10.1016/j.chemosphere.2024.142515 -
Dalton Transactions (Cambridge, England... Jun 2024The second near-infrared window (NIR-II) in the range of 1000-1400 nm is ideal for imaging and sensing through reduced scattering, absorption, and autofluorescence....
The second near-infrared window (NIR-II) in the range of 1000-1400 nm is ideal for imaging and sensing through reduced scattering, absorption, and autofluorescence. However, there are only a few nanophosphor systems with emission in the NIR-II region. Here, we report on Mn-doped Ba(PO)Cl nanoparticles (BPCl:Mn NPs, < 50 nm) toward NIR-II temperature sensing. BPCl:Mn NPs are made by a two-step (hydrothermal and anion exchange) method. XRD, SEM, and TEM results showed that the as-prepared BPCl:Mn NPs show high crystallinity, uniform size, and sphere-like morphology. The nanoparticles exhibit a broad excitation band of 500-850 nm and a temperature-sensitive peak emission at 1175 nm in the NIR-II range. NIR-II temperature sensing by E emission intensity is demonstrated with good linear fitting ( = 0.9895), high sensitivity (2.30% at 373 K), and good repeatability (99.0%). Thus, our study provides a path to develop a new NIR-II thermometer based on tetrahedral Mn(V) coordination.
PubMed: 38829195
DOI: 10.1039/d4dt01440e -
Research and Reports in Urology 2024To assess the correlation of attenuation value measured as HU in Non-contrast computed tomography, stone size, location, fibre size and stone composition with Holmium:...
OBJECTIVE
To assess the correlation of attenuation value measured as HU in Non-contrast computed tomography, stone size, location, fibre size and stone composition with Holmium: yttrium-aluminium garnet (Ho: YAG) laser parameters including, cumulative laser energy and final laser time.
MATERIALS AND METHODS
We prospectively analyzed 118 patients undergoing flexible/semirigid ureteroscopy and Holmium: YAG laser lithotripsy from October 2022 to October 2023 at Mogadishu Urological Centre. Our study parameters encompass preoperative stone characteristics determined in NCCT (stone size, attenuation value, and stone location), fibre size, cumulative laser energy and time, overall operative time, and postoperative stone composition analysis.
RESULTS
There were 118 patients eligible for our prospective study. In the logistic regression model for retrograde intrarenal surgery with a fibre size of 272μm, cumulative laser energy showed a significant difference among stone size, location, fibre size, and calcium oxalate stones (P > 0.05). However, no significant difference was noticed in the attenuation value (P = 0.078) (R2 = 0.053). Our analysis showed a positive significance among all the parameters (P < 0.05) for laser time. In logistic regression for a rigid ureteroscope with a fibre size of 365μm, cumulative laser energy showed a significant difference between the location stone and fibre size (P < 0.05) (R2 = 0.09). However, no significant difference was seen among stone size, attenuation value, and calcium oxalate stones (P > 0.05). For laser time, our analysis showed a positive significance among all parameters except the calcium oxalate stones, which showed no significant difference (P > 0.05).
CONCLUSION
Our study showed that stone location, hardness, and fibre size are the most critical factors influencing the outcome of Ho: YAG laser parameters. The study revealed that CaOMH stones require more time to disintegrate into smaller ones, while PH-dependent stones such as carbonate apatite may require less time to fragment.
PubMed: 38826868
DOI: 10.2147/RRU.S464098