RESUMEN
The rising prevalence of bone injuries has increased the demand for minimally invasive treatments. Microbead hydrogels, renowned for cell encapsulation, provide a versatile substrate for bone tissue regeneration. They deliver bioactive agents, support cell growth, and promote osteogenesis, aiding bone repair and regeneration. In this study, we synthesized superparamagnetic iron oxide nanoparticles (Sp) coated with a calcium phosphate layer (m-Sp), achieving a distinctive flower-like micro-cluster morphology. Subsequently, sodium alginate (SA) microbead hydrogels containing m-Sp (McSa@m-Sp) were fabricated using a dropping gelation strategy. McSa@m-Sp is magnetically targetable, enhance cross-linking, control degradation rates, and provide strong antibacterial activity. Encapsulation studies with MC3T3-E1 cells revealed enhanced viability and proliferation. These studies also indicated significantly elevated alkaline phosphatase (ALP) activity and mineralization in MC3T3-E1 cells, as confirmed by Alizarin Red S (ARS) and Von Kossa staining, along with increased collagen production within the McSa@m-Sp microbead hydrogels. Immunocytochemistry (ICC) and gene expression studies supported the osteoinductive potential of McSa@m-Sp, showing increased expression of osteogenic markers including RUNX-2, collagen-I, osteopontin, and osteocalcin. Thus, McSa@m-Sp microbead hydrogels offer a promising strategy for multifunctional scaffolds in bone tissue engineering.
Asunto(s)
Alginatos , Regeneración Ósea , Fosfatos de Calcio , Proliferación Celular , Hidrogeles , Osteogénesis , Alginatos/química , Alginatos/farmacología , Animales , Ratones , Fosfatos de Calcio/química , Fosfatos de Calcio/farmacología , Osteogénesis/efectos de los fármacos , Hidrogeles/química , Hidrogeles/farmacología , Regeneración Ósea/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Ingeniería de Tejidos/métodos , Línea Celular , Nanopartículas Magnéticas de Óxido de Hierro/química , Antibacterianos/farmacología , Antibacterianos/químicaRESUMEN
Gene therapy using a protein-based CRISPR system in the brain has practical limitations due to current delivery systems, especially in the presence of arterial occlusion. To overcome these obstacles and improve stability, we designed a system for intranasal administration of gene therapy for the treatment of ischemic stroke. Methods: Nanoparticles containing the protein-based CRISPR/dCas9 system targeting Sirt1 were delivered intranasally to the brain in a mouse model of ischemic stroke. The CRISPR/dCas9 system was encapsulated with calcium phosphate (CaP) nanoparticles to prevent them from being degraded. They were then conjugated with ß-hydroxybutyrates (bHb) to target monocarboxylic acid transporter 1 (MCT1) in nasal epithelial cells to facilitate their transfer into the brain. Results: Human nasal epithelial cells were shown to uptake and transfer nanoparticles to human brain endothelial cells with high efficiency in vitro. The intranasal administration of the dCas9/CaP/PEI-PEG-bHb nanoparticles in mice effectively upregulated the target gene, Sirt1, in the brain, decreased cerebral edema and increased survival after permanent middle cerebral artery occlusion. Additionally, we observed no significant in vivo toxicity associated with intranasal administration of the nanoparticles, highlighting the safety of this approach. Conclusion: This study demonstrates that the proposed protein-based CRISPR-dCas9 system targeting neuroprotective genes in general, and SIRT1 in particular, can be a potential novel therapy for acute ischemic stroke.
Asunto(s)
Administración Intranasal , Encéfalo , Modelos Animales de Enfermedad , Terapia Genética , Accidente Cerebrovascular Isquémico , Nanopartículas , Sirtuina 1 , Animales , Ratones , Humanos , Accidente Cerebrovascular Isquémico/terapia , Accidente Cerebrovascular Isquémico/genética , Nanopartículas/administración & dosificación , Terapia Genética/métodos , Sirtuina 1/genética , Sirtuina 1/metabolismo , Encéfalo/metabolismo , Masculino , Fosfatos de Calcio , Sistemas CRISPR-Cas , Ratones Endogámicos C57BL , Células Endoteliales/metabolismo , Isquemia Encefálica/terapia , Isquemia Encefálica/genética , Infarto de la Arteria Cerebral Media/terapia , Infarto de la Arteria Cerebral Media/genética , Células Epiteliales/metabolismoRESUMEN
The development of synthetic bone substitutes that equal or exceed the efficacy of autologous graft remains challenging. In this study, a rat calvarial defect model was used as a reference to investigate the influence of composition and architecture of 3D-printed cement, with or without bioactives, on tissue regeneration. Printable cement pastes were formulated by combining hyaluronic acid and cement precursors. Cementitious scaffolds were printed with 3 different patterns. After 7 weeks of implantation with or without bone marrow, multiparametric qualitative and quantitative assessments were performed using µCT, SEM, and histology. None of the set-up strategies was as efficient as autologous cancellous bone graft to repair calvarial defects. Nonetheless, the presence of scaffold improved the skull vault closure, particularly when the scaffold was soaked in total bone marrow before implantation. No significant effect of scaffold macro-architecture was observed on tissue mineralization. Magnesium phosphate-based scaffolds (MgP) seemed to induce higher bone formation than their calcium-phosphate-based counterparts. They also displayed a quicker biodegradation and sparse remaining material was found after 7 weeks of implantation. Although further improvements are required to reach clinical settings, this study demonstrated the potential of organo-mineral cements for bone regeneration and highlighted the peculiar properties of MgP-based cements.
Asunto(s)
Regeneración Ósea , Impresión Tridimensional , Cráneo , Andamios del Tejido , Animales , Regeneración Ósea/efectos de los fármacos , Andamios del Tejido/química , Ratas , Cráneo/efectos de los fármacos , Sustitutos de Huesos/química , Sustitutos de Huesos/farmacología , Fosfatos de Calcio/química , Fosfatos de Calcio/farmacología , Masculino , Cementos para Huesos/farmacología , Cementos para Huesos/química , Fosfatos/química , Osteogénesis/efectos de los fármacos , Microtomografía por Rayos X , Compuestos de MagnesioRESUMEN
Doping of brushite cements with metal ions can entail many positive effects on biological and physicochemical properties. Cu2+ ions are known to exhibit antibacterial properties and can additionally have different positive effects on cells as trace elements, whereas high Cu2+ concentrations are cytotoxic. For therapeutical applications of bone cement, a combination of good biocompatibility and sufficient mechanical properties is required. Therefore, the aim of this study was to investigate different physicochemical and biological aspects, relevant for application, of a brushite cement with Cu2+-doped ß-tricalcium phosphate, monocalcium phosphate monohydrate and phytic acid as setting retarder. Additionally, the ion release was compared with a cement with citric acid as setting retarder. The investigated cements showed good injectability coefficients, as well as compressive strength values sufficient for application. Furthermore, no antibacterial effects were detected irrespective of the Cu2+ concentration or the bacterial strain. The cell experiments with eluate samples showed that the viability of MC3T3-E1 cells tended to decrease with increasing Cu2+ concentration in the cement. It is suggested that these biological responses are caused by the difference in the Cu2+ release from the hardened cement depending on the solvent medium. Furthermore, the cements showed a steady release of Cu2+ ions to a lesser extent in comparison with a cement with citric acid as setting retarder, where a burst release of Cu2+ was observed. In conclusion, despite the anticipated antibacterial effect of Cu2+-doped cements was lacking and mammalian cell viability was slightly affected, Cu2+-concentrations maintained the physicochemical properties as well as the compressive strength of cements and the slow ion release from cements produced with phytic acid is considered advantageous compared to citric acid-based formulations.
Asunto(s)
Cementos para Huesos , Fosfatos de Calcio , Cobre , Ensayo de Materiales , Ratones , Animales , Cobre/química , Cementos para Huesos/química , Cementos para Huesos/farmacología , Fosfatos de Calcio/química , Fosfatos de Calcio/farmacología , Antibacterianos/química , Antibacterianos/farmacología , Fuerza Compresiva , Supervivencia Celular/efectos de los fármacos , Línea Celular , Células 3T3 , Ácido Cítrico/químicaRESUMEN
The interconnected structures in a 3D scaffold allows the movement of cells and nutrients. Therefore, this study aimed to investigate the in-vivo bioactivity of 3D-printed ß-tricalcium phosphate (ß-TCP) and hydroxyapatite (HAP) scaffolds that replicate biological bone. This study included 24-week-old male New Zealand white rabbits. A cylindrical bone defect with a diameter of 4.5 mm and a depth of 8 mm was created in the lateral aspect of the distal femur. A 3D-printed scaffold was implanted in the right femur (experimental side), whereas the left femur was kept free of implantation (control side). Micro-CT analysis and histological observations of the bone defect site were conducted at 4, 8, and 12 weeks postoperatively to track the bone repair progress. No evidence of new bone tissue formation was found in the medullary cavity of the bone defect on the control side. In contrast, on the experimental side, the 3D scaffold demonstrated sufficient bioactivity, leading to the growth of new bone tissue. Over time, new bone tissue gradually extended from the periphery toward the center, a phenomenon evident in both micro-CT images and biopsy staining. In the current study, we observed that the cells involved in bone metabolism adhered, spread, and proliferated on our newly designed 3D-printed scaffold with a bone microstructure. Therefore, it is suggested that this scaffold has sufficient bioactivity to induce new bone formation and could be expected to be a more useful artificial bone than the existing version.
Asunto(s)
Regeneración Ósea , Fosfatos de Calcio , Fémur , Impresión Tridimensional , Ingeniería de Tejidos , Andamios del Tejido , Microtomografía por Rayos X , Conejos , Animales , Fosfatos de Calcio/química , Andamios del Tejido/química , Masculino , Regeneración Ósea/efectos de los fármacos , Fémur/patología , Ingeniería de Tejidos/métodos , Osteogénesis/fisiología , Osteogénesis/efectos de los fármacos , Durapatita/química , Huesos/patología , Sustitutos de Huesos/química , Sustitutos de Huesos/farmacología , Ensayo de Materiales , Materiales Biocompatibles/químicaRESUMEN
BACKGROUND: Tyrosine-rich amelogenin peptide (TRAP) is the main amelogenin digestion product in the developmental enamel matrix. It has been shown to promote remineralization of demineralized enamel in our previous study. However, direct evidence of the effect of TRAP on the morphology and nanostructure of crystal growth on an enamel surface has not been reported. This study aimed to examine the effect of TRAP on the morphology of calcium phosphate crystals grown on early enamel erosion using a pH-cycling model. METHODS: Eroded lesions were produced in human premolars by 30-second immersion in 37% phosphoric acid. Forty-five samples of eroded human premolar enamel blocks were selected and randomly divided into 3 groups: deionized water (DDW, negative control); 100 µg/mL TRAP, and 2 ppm sodium fluoride (NaF, positive control group). For 14 days, the specimens were exposed to a pH-cycling model. Using scanning electron microscopy (SEM) and atomic force microscopy (AFM) methods, the surface morphology, calcium-phosphorus ratio, and enamel surface roughness were examined. X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR) were used to assess crystal characteristics. RESULTS: After pH-cycling, compared to the two control groups, the surface of the eroded enamel of the peptide TRAP group shows a large number of new, densely arranged rod-like crystals, parallel to each other, regularly arranged, forming an ordered structure, with crystal morphology similar to that of natural enamel. The crystals are mostly hydroxyapatite (HA). CONCLUSION: This study demonstrates that the peptide TRAP modulates the formation of hydroxyapatite in eroded enamel and that the newly formed crystals resemble natural enamel crystals and promote the remineralization of enamel, providing a promising biomaterial for remineralization treatment of enamel lesions.
Asunto(s)
Amelogenina , Esmalte Dental , Microscopía Electrónica de Rastreo , Erosión de los Dientes , Remineralización Dental , Difracción de Rayos X , Humanos , Remineralización Dental/métodos , Esmalte Dental/efectos de los fármacos , Erosión de los Dientes/patología , Concentración de Iones de Hidrógeno , Amelogenina/uso terapéutico , Amelogenina/farmacología , Espectroscopía Infrarroja por Transformada de Fourier , Microscopía de Fuerza Atómica , Fosfatos de Calcio/farmacología , Propiedades de Superficie , Diente Premolar , CristalizaciónRESUMEN
BACKGROUND: Alveolar Bone loss occurs frequently during the first six months after tooth extraction. Various studies have proposed different methods to reduce as much as possible the atrophy of the alveolar ridge after tooth extraction. Filling the socket with biomaterials after extraction can reduce the resorption of the alveolar ridge. We compared the height of the alveolar process at the mesial and distal aspects of the extraction site and the resorption rate was calculated after the application of HA/ß-TCP or synthetic co-polymer polyglycolic - polylactic acid PLGA mixed with blood to prevent socket resorption immediately and after tooth extraction. METHODS: The study was conducted on 24 extraction sockets of impacted mandibular third molars bilaterally, vertically, and completely covered, with a thin bony layer. HA/ß-TCP was inserted into 12 of the dental sockets immediately after extraction, and the synthetic polymer PLGA was inserted into 12 of the dental sockets. All sockets were covered completely with a full-thickness envelope flap. Follow-up was performed for one year after extraction, using radiographs and stents for the vertical alveolar ridge measurements. RESULTS: The mean resorption rate in the HA/ß-TCP and PLGA groups was ± 1.23 mm and ± 0.1 mm, respectively. A minimal alveolar bone height reduction of HA/ß-TCP was observed after 9 months, the reduction showed a slight decrease to 0.93 mm, while this rate was 0.04 mm after 9 months in the PLGA group. Moreover, the bone height was maintained after three months, indicating a good HA/ß-TCP graft performance in preserving alveolar bone (1.04 mm) while this rate was (0.04 mm) for PLGA. CONCLUSION: The PLGA graft demonstrated adequate safety and efficacy in dental socket preservation following tooth extraction. However, HA/ß-TCP causes greater resorption at augmented sites than PLGA, which clinicians should consider during treatment planning.
Asunto(s)
Pérdida de Hueso Alveolar , Sustitutos de Huesos , Ácido Láctico , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Extracción Dental , Alveolo Dental , Humanos , Alveolo Dental/cirugía , Pérdida de Hueso Alveolar/prevención & control , Sustitutos de Huesos/uso terapéutico , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/uso terapéutico , Masculino , Femenino , Ácido Láctico/uso terapéutico , Adulto , Ácido Poliglicólico/uso terapéutico , Proceso Alveolar/patología , Tercer Molar/cirugía , Diente Impactado/cirugía , Estudios de Seguimiento , Adulto Joven , Colgajos Quirúrgicos , Materiales Biocompatibles/uso terapéutico , Aumento de la Cresta Alveolar/métodos , Hidroxiapatitas/uso terapéutico , Mandíbula/cirugía , Fosfatos de Calcio/uso terapéutico , Resultado del TratamientoRESUMEN
Bioluminescence imaging (BLI) is an important noninvasive optical imaging technique that has been widely used to monitor many biological processes due to its high sensitivity, resolution, and signal-to-noise ratio. However, the BLI technique based on the firefly luciferin-luciferase system is limited by the expression of exogenous luciferase and the short half-life of firefly luciferin, which pose challenges for long-term tracking in vivo. To solve the problems, here we rationally designed an intelligent strategy for persistent BLI in tumors by combining luciferase-loaded calcium phosphate nanoparticles (Luc@CaP NPs) to provide luciferase and the probe Cys(SEt)-Lys-CBT (CKCBT) to slowly produce the luciferase substrate amino luciferin (Am-luciferin). Luc@CaP NPs constructed with CaP as a carrier could enable luciferase activity to be maintained in vivo for at least 12 h. And compared to the conventional substrate luciferin, CKCBT apparently prolonged the BL time by up to 2 h through GSH-induced intracellular self-assembly and subsequent protease degradation-induced release of Am-luciferin. We anticipate that this strategy could be applied for clinical translation in more disease diagnosis and treatment in the near future.
Asunto(s)
Neoplasias de la Mama , Fosfatos de Calcio , Luciferasas , Mediciones Luminiscentes , Nanopartículas , Fosfatos de Calcio/química , Nanopartículas/química , Animales , Mediciones Luminiscentes/métodos , Humanos , Luciferasas/metabolismo , Luciferasas/química , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/patología , Femenino , Ratones , Imagen Óptica , Ratones Endogámicos BALB C , Línea Celular Tumoral , Ratones DesnudosRESUMEN
Artificial bone is the alternative candidate for the bone defect treatment under the circumstance that there exits enormous challenge to remedy the bone defect caused by attributes like trauma and tumors. However, the impact of pore size discrepancy for regulating new bone generation is still ambiguous. Using direct 3D printing technology, customized 3D polycaprolactone/ß-tricalcium phosphate (PCL/ß-TCP) artificial bones with different structural pore sizes (1.8, 2.0, 2.3, 2.5, and 2.8 mm) were successfully prepared, abbreviated as the 3D PCL/ß-TCP. 3D PCL/ß-TCP exhibited a 3D porous structure morphology similar to natural bone and possessed outstanding mechanical properties. Computational fluid dynamics analysis indicated that as the structural pore size increased from 1.8 to 2.8 mm, both velocity difference (from 4.64 × 10-5to 7.23 × 10-6m s-1) and depressurization (from 7.17 × 10-2to 2.25 × 10-2Pa) decreased as the medium passed through.In vitrobiomimetic mineralization experiments confirmed that 3D PCL/ß-TCP artificial bones could induce calcium-phosphate complex generation within 4 weeks. Moreover, CCK-8 and Calcein AM live cell staining experiments demonstrated that 3D PCL/ß-TCP artificial bones with different structural pore sizes exhibited advantageous cell compatibility, promoting MC3T3-E1 cell proliferation and adhesion.In vivoexperiments in rats further indicated that 3D PCL/ß-TCP artificial bones with different structural pore sizes promoted new bone formation, with the 2.5 mm group showing the most significant effect. In conclusion, 3D PCL/ß-TCP artificial bone with different structural pore sizes could promote new bone formation and 2.5 mm group was the recommended for the bone defect repair.
Asunto(s)
Sustitutos de Huesos , Fosfatos de Calcio , Ensayo de Materiales , Poliésteres , Impresión Tridimensional , Andamios del Tejido , Fosfatos de Calcio/química , Poliésteres/química , Animales , Porosidad , Sustitutos de Huesos/química , Ratas , Andamios del Tejido/química , Ratones , Huesos/metabolismo , Materiales Biocompatibles/química , Osteogénesis/efectos de los fármacos , Ingeniería de Tejidos/métodos , Osteoblastos/citología , Ratas Sprague-Dawley , Masculino , Proliferación Celular/efectos de los fármacos , Regeneración Ósea/efectos de los fármacosRESUMEN
Tumor acidity-driven nanomotors may offer robust propulsion for tumor-specific penetrating drug delivery. Herein, an acidity-actuated poly(amino acid) calcium phosphate (CaP) hybrid nanomotor (PCaPmotor) was designed, using a mPEG-PAsp-PPhe@THZ531 micelle (Poly@THZ) for CaP mineralization accompanied by αPD-L1 antibody encapsulation. Dissolution of the CaP layer in an acidic tumor environment gave off heat energy to propel the nanomotor to augment the cellular uptake and penetration into deeply seated cancer cells while facilitating αPD-L1 release. THZ531 delivered by the PCaPmotor inhibited CDK12 and its down-streamed phosphorylation of RNAP-II to increase the cancer immunogenicity events such as the DNA damage, cell apoptosis, immunogenic cell death, lysosomal function disturbance, and MHC-I upregulation. THZ531 and αPD-L1 cosupplied by PCaPmotor significantly increased the frequency of DCs maturation and intratumoral infiltration of CTLs, but the two free drugs did not. Consequently, the PCaP@THZ/αPD-L1 nanomotor resulted in synergistic anticancer immunotherapy in mice. This acid-actuated PCaPmotor represented a new paradigm for penetrating drug delivery.
Asunto(s)
Fosfatos de Calcio , Sistemas de Liberación de Medicamentos , Inmunoterapia , Fosfatos de Calcio/química , Animales , Ratones , Humanos , Línea Celular Tumoral , Polímeros/química , Micelas , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/administración & dosificación , Concentración de Iones de Hidrógeno , Neoplasias/terapia , Neoplasias/tratamiento farmacológico , Antígeno B7-H1 , Nanopartículas/químicaRESUMEN
Target values for 25-hydroxy vitamin D and 1,25(OH)2D or 1,25-dihydroxy vitamin D remain a topic of debate among clinicians. We analysed data collected from December 2012 to April 2020 from two cohorts. Cohort A, comprising 455,062 subjects, was used to investigate the relationship between inflammatory indicators (white blood cell [WBC] count and C-reactive protein [CRP]) and 25(OH)D/1,25(OH)2D. Cohort B, including 47,778 subjects, was used to investigate the connection between 25(OH)D/1,25(OH)2D and mineral metabolism markers (phosphate, calcium, and intact parathyroid hormone [iPTH]). Quadratic models fit best for all tested correlations, revealing U-shaped relationships between inflammatory indicators and 25(OH)D and 1,25(OH)2D. Minimal CRP and WBC counts were observed at 1,25(OH)2D levels of 60 pg/mL and at 25(OH)D levels of 32 ng/mL, as well as of 42 ng/mL, respectively. iPTH correlated inversely with both 1,25(OH)2D and 25(OH)D, while phosphate as well as calcium levels positively correlated with both vitamin D forms. Calcium-phosphate product increased sharply when 25(OH)D was more than 50 ng/mL, indicating a possible risk for vascular calcification. Multiple regression analyses confirmed that these correlations were independent of confounders. This study suggests target values for 25(OH)D between 30-50 ng/mL and for 1,25(OH)2D between 50-70 pg/mL, based particularly on their associations with inflammation but also with mineral metabolism markers. These findings contribute to the ongoing discussion around ideal levels of vitamin D but require support from independent studies with data on clinical endpoints.
Asunto(s)
Calcio , Inflamación , Vitamina D , Humanos , Vitamina D/sangre , Vitamina D/análogos & derivados , Femenino , Masculino , Inflamación/sangre , Persona de Mediana Edad , Calcio/sangre , Hormona Paratiroidea/sangre , Proteína C-Reactiva/análisis , Proteína C-Reactiva/metabolismo , Adulto , Estudios de Cohortes , Biomarcadores/sangre , Anciano , Fosfatos/sangre , Fosfatos de Calcio/sangre , Recuento de Leucocitos , Deficiencia de Vitamina D/sangreRESUMEN
Allogeneic bone grafts are used to treat bone defects in orthopedic surgery, but the osteogenic potential of artificial bones remains a challenge. In this study, we developed a ß-tricalcium phosphate (ß-TCP) formulation containing MgO, ZnO, SrO, and SiO2 and compared its bone-forming ability with that of ß-TCP without biological elements. We prepared ß-TCP discs with 60% porosity containing 1.0 wt% of these biological elements. ß-TCP scaffolds were loaded with bone marrow-derived mesenchymal stem cells (BMSC) from 7-week-old male rats and cultured for 2 weeks. ALP activity and mRNA expression of osteogenic markers were evaluated. In addition, scaffolds were implanted subcutaneously in rats and analyzed after 7 weeks. In vitro, the MgO group showed lower Ca concentrations and higher osteogenic marker expression compared to controls. In vivo, the MgO group showed higher ALP activity compared to controls, and RT-qPCR analysis showed significant expression of BMP2 and VEGF. Histopathology, fluorescent immunostaining, and micro-CT also showed relatively better bone formation in the MgO group. ß-TCP with MgO may enhance bone morphology in vitro and in vivo and improve the prognosis of patients with substantial and refractory bone defects.
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Fosfatos de Calcio , Óxido de Magnesio , Células Madre Mesenquimatosas , Osteogénesis , Andamios del Tejido , Animales , Osteogénesis/efectos de los fármacos , Fosfatos de Calcio/farmacología , Fosfatos de Calcio/química , Ratas , Masculino , Células Madre Mesenquimatosas/metabolismo , Células Madre Mesenquimatosas/efectos de los fármacos , Células Madre Mesenquimatosas/citología , Óxido de Magnesio/farmacología , Óxido de Magnesio/química , Andamios del Tejido/química , Proteína Morfogenética Ósea 2/metabolismo , Proteína Morfogenética Ósea 2/genética , Microtomografía por Rayos X , Ratas Sprague-Dawley , Fosfatasa Alcalina/metabolismo , Células Cultivadas , Ingeniería de Tejidos/métodos , Diferenciación Celular/efectos de los fármacos , Factor A de Crecimiento Endotelial Vascular/metabolismo , Factor A de Crecimiento Endotelial Vascular/genéticaRESUMEN
ARTICLE TITLE AND BIBLIOGRAPHIC INFORMATION: Effectiveness of Calcium Phosphate derivative agents on the prevention and remineralization of caries among children- A systematic review & meta-analysis of randomized controlled trials. Singal K, Sharda S, Gupta A, Malik VS, Singh M, Chauhan A, Agarwal A, Pradhan P, Singh M. J Evid Based Dent Pract. 2022; 22(3):101746. SOURCE OF FUNDING: Indian Council of Medical Research. TYPE OF STUDY/DESIGN: Systematic review with meta-analysis.
Asunto(s)
Fosfatos de Calcio , Caries Dental , Fluoruros , Remineralización Dental , Niño , Humanos , Fosfatos de Calcio/uso terapéutico , Cariostáticos/uso terapéutico , Cariostáticos/farmacología , Cariostáticos/administración & dosificación , Caries Dental/prevención & control , Fluoruros/administración & dosificación , Fluoruros/uso terapéutico , Ensayos Clínicos Controlados Aleatorios como Asunto , Metaanálisis como Asunto , Revisiones Sistemáticas como AsuntoRESUMEN
The critical role of the human gut microbiota in kidney stone formation remains largely unknown, due to the low taxonomic resolution of previous sequencing technologies. Therefore, this study aimed to explore the gut microbiota using high-throughput sequencing to provide valuable insights and identify potential bacterial species and metabolite roles involved in kidney stone formation. The overall gut bacterial community and its potential functions in healthy participants and patients were examined using PacBio sequencing targeting the full-length 16S rRNA gene, coupled with stone and statistical analyses. Most kidney stones comprised calcium oxalate and calcium phosphate (75%), pure calcium oxalate (20%), and calcium phosphate and magnesium phosphate (5%), with higher content of Ca (130,510.5 ± 108,362.7 ppm) followed by P (18,746.4 ± 23,341.2 ppm). The microbial community structure was found to be weaker in patients' kidney stone samples, followed by patients' stool samples, than in healthy participants' stool samples. The most abundant bacterial species in kidney stone samples was uncultured Morganella, whereas that in patient and healthy participant stool samples was Bacteroides vulgatus. Similarly, Akkermansia muciniphila was significantly enriched in patient stool samples at the species level, whereas Bacteroides plebeius was significantly enriched in kidney stone samples than that in healthy participant stool samples. Three microbial metabolic pathways, TCA cycle, fatty acid oxidation, and urea cycle, were significantly enriched in kidney stone patients compared to healthy participants. Inferring bacteria at the species level revealed key players in kidney stone formation, enhancing the clinical relevance of gut microbiota.
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Heces , Microbioma Gastrointestinal , Cálculos Renales , ARN Ribosómico 16S , Humanos , Cálculos Renales/microbiología , Cálculos Renales/metabolismo , Microbioma Gastrointestinal/genética , ARN Ribosómico 16S/genética , Masculino , Heces/microbiología , Femenino , Persona de Mediana Edad , Adulto , Fosfatos de Calcio/metabolismo , Secuenciación de Nucleótidos de Alto Rendimiento , Oxalato de Calcio/metabolismo , Oxalato de Calcio/análisis , Bacterias/genética , Bacterias/metabolismo , Bacterias/aislamiento & purificación , Bacterias/clasificación , AkkermansiaRESUMEN
Bone regeneration often fails due to implants/grafts lacking vascular supply, causing necrotic tissue and poor integration. Microsurgical techniques are used to overcome this issue, allowing the graft to anastomose. These techniques have limitations, including severe patient morbidity and current research focuses on stimulating angiogenesis in situ using growth factors, presenting limitations, such as a lack of control and increased costs. Non-biological stimuli are necessary to promote angiogenesis for successful bone constructs. Recent studies have reported that bioactive glass dissolution products, such as calcium-releasing nanoparticles, stimulate hMSCs to promote angiogenesis and new vasculature. Moreover, the effect of 3D microporosity has also been reported to be important for vascularisation in vivo. Therefore, we used room-temperature extrusion 3D printing with polylactic acid (PLA) and calcium phosphate (CaP) based glass scaffolds, focusing on geometry and solvent displacement for scaffold recovery. Combining both methods enabled reproducible control of 3D structure, porosity, and surface topography. Scaffolds maintained calcium ion release at physiological levels and supported human mesenchymal stem cell proliferation. Scaffolds stimulated the secretion of vascular endothelial growth factor (VEGF) after 3 days of culture. Subcutaneous implantation in vivo indicated good scaffold integration and blood vessel infiltration as early as one week after. PLA-CaP scaffolds showed increased vessel maturation 4 weeks after implantation without vascular regression. Results show PLA/CaP-based glass scaffolds, made via controlled 3D printing, support angiogenesis and vessel maturation, promising improved vascularization for bone regeneration.
Asunto(s)
Fosfatos de Calcio , Vidrio , Neovascularización Fisiológica , Poliésteres , Impresión Tridimensional , Andamios del Tejido , Humanos , Poliésteres/química , Poliésteres/farmacología , Neovascularización Fisiológica/efectos de los fármacos , Andamios del Tejido/química , Vidrio/química , Fosfatos de Calcio/química , Fosfatos de Calcio/farmacología , Animales , Regeneración Ósea/efectos de los fármacos , Regeneración Ósea/fisiología , Células Madre Mesenquimatosas/efectos de los fármacos , Células Madre Mesenquimatosas/citología , Ingeniería de Tejidos/métodos , Huesos/irrigación sanguínea , Huesos/efectos de los fármacos , Factor A de Crecimiento Endotelial Vascular/metabolismo , Ratones , Porosidad , Proliferación Celular/efectos de los fármacosRESUMEN
Visceral Leishmaniasis is a serious public health problem caused by Leishmania species parasites. Approximately 500 thousand people get Visceral Leishmaniasis (VL) every year. An effective and reliable vaccine against the disease has still not been formulated. Choosing the right adjuvant is important to increase immunogenicity in vaccines prepared with total antigens. In this study, we investigate the ideal adjuvant for use in vaccine formulations against VL. For this purpose, Leishmania antigens (FTLA) obtained from L. infantum parasites by the freeze-thaw method and three different adjuvants (alum-saponin and calcium phosphate) were used. The effectiveness of the formulations was investigated in vitro by cell viability analysis and determination of nitric oxide and cytokine production abilities in J774 macrophage cells. According to the study results, it was determined that formulations prepared with calcium phosphate produced 72% more NO and approximately 7.2 times more IL-12 cytokine. The results obtained showed that calcium phosphate salts can be used as ideal adjuvants in vaccine research against leishmaniasis.
Asunto(s)
Antígenos de Protozoos , Leishmania infantum , Vacunas contra la Leishmaniasis , Animales , Ratones , Vacunas contra la Leishmaniasis/inmunología , Leishmania infantum/inmunología , Antígenos de Protozoos/inmunología , Línea Celular , Macrófagos/inmunología , Vacunas de Productos Inactivados/inmunología , Vacunas de Productos Inactivados/administración & dosificación , Óxido Nítrico/metabolismo , Fosfatos de Calcio , Citocinas/metabolismo , Adyuvantes de Vacunas , Leishmaniasis Visceral/prevención & control , Leishmaniasis Visceral/inmunología , Saponinas/farmacología , Compuestos de Alumbre/administración & dosificación , Adyuvantes Inmunológicos/administración & dosificación , Supervivencia Celular/efectos de los fármacosRESUMEN
Osteomyelitis is an inflammation of bone tissue usually caused by pyogenic bacteria. The most recurrent clinical approach consists of bone debridement followed by parenteral administration of antibiotics. However, systemic antibiotic treatment has limitations regarding absorption rate and bioavailability over time. The main challenge of osteomyelitis treatment consists of coupling the persistent infection treatment with the regeneration of the bone debrided. In this work, we developed an injectable drug delivery system based on poloxamer 407 hydrogel containing undoped Mg, Zn-doped tricalcium phosphate (ß-TCP), and teicoplanin, a broad-spectrum antibiotic. We evaluated how the addition of teicoplanin and ß-TCP affected the micellization, gelation, particle size, and surface charge of the hydrogel. Later, we studied the hydrogel degradation and drug delivery kinetics. Finally, the bactericidal, biocompatibility, and osteogenic properties were evaluated through in vitro studies and confirmed by in vivo Wistar rat models. Teicoplanin was found to be encapsulated in the corona portions of the hydrogel micelles, yielding a bigger hydrodynamics radius. The encapsulated teicoplanin showed a sustained release over the evaluated period, enough to trigger antibacterial properties against Gram-positive bacteria. Besides, the formulations were biocompatible and showed bone healing ability and osteogenic properties. Finally, in vivo studies confirmed that the proposed locally injected formulations yielded osteomyelitis treatment with superior outcomes than parenteral administration while promoting bone regeneration. In conclusion, the presented formulations are promising drug delivery systems for osteomyelitis treatment and deserve further technological improvements.
Asunto(s)
Antibacterianos , Fosfatos de Calcio , Hidrogeles , Osteogénesis , Osteomielitis , Ratas Wistar , Teicoplanina , Osteomielitis/tratamiento farmacológico , Osteomielitis/microbiología , Animales , Fosfatos de Calcio/química , Teicoplanina/administración & dosificación , Teicoplanina/farmacología , Teicoplanina/química , Antibacterianos/administración & dosificación , Antibacterianos/farmacología , Antibacterianos/química , Ratas , Hidrogeles/química , Hidrogeles/administración & dosificación , Osteogénesis/efectos de los fármacos , Sistemas de Liberación de Medicamentos/métodos , Humanos , Staphylococcus aureus/efectos de los fármacos , Poloxámero/químicaRESUMEN
The efficiency of synthetic bone grafts can be evaluated either in osseous sites, to analyze osteoconduction or ectopically, in intramuscular or subcutaneous sites, to assess osteoinduction. Bone regeneration is usually evaluated in terms of the presence and quantity of newly formed bone, but little information is normally provided on the quality of this bone. Here, we propose a novel approach to evaluate bone quality by the combined use of spectroscopy techniques and nanoindentation. Calcium phosphate scaffolds with different architectures, either foamed or 3D-printed, that were implanted in osseous or intramuscular defects in Beagle dogs for 6 or 12 weeks were analyzed. ATR-FTIR and Raman spectroscopy were performed, and mineral-to-matrix ratio, crystallinity, and mineral and collagen maturity were calculated and mapped for the newly regenerated bone and the mature cortical bone from the same specimen. For all the parameters studied, the newly-formed bone showed lower values than the mature host bone. Hardness and elastic modulus were determined by nanoindentation and, in line with what was observed by spectroscopy, lower values were observed in the regenerated bone than in the cortical bone. While, as expected, all techniques pointed to an increase in the maturity of the newly-formed bone between 6 and 12 weeks, the bone found in the intramuscular samples after 12 weeks presented lower mineralization than the intraosseous counterparts. Moreover, scaffold architecture also played a role in bone maturity, with the foamed scaffolds showing higher mineralization and crystallinity than the 3D-printed scaffolds after 12 weeks.
Asunto(s)
Regeneración Ósea , Andamios del Tejido , Animales , Perros , Regeneración Ósea/fisiología , Andamios del Tejido/química , Espectrometría Raman/métodos , Fosfatos de Calcio/química , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Huesos/química , Huesos/fisiología , Impresión TridimensionalRESUMEN
Dental caries is a worldwide public healthcare concern, and is closely related to the acidic environment that caused by bacterial decomposition of food. In this study, a two-step ion exchange liquid-phase stripping method was applied to strip out vermiculite (VMT) nanosheets, then amorphous calcium phosphate (ACP) and dextran were inserted between the VMT nanosheets interlayer to obtain a composite two-dimension nanosheets (VMT/ACP/Dextran). VMT/ACP/Dextran composite nanosheets exhibited excellent biocompatibility and could provide exogenous Ca2+and PO43- from ACP, provide SiO44-, Mg2+, Fe2+ and obtain buffering pH and antibacterial properties from VMT, as well as improve suspension stability and targeting Streptococcus mutans through glucan. The in vitro study showed that the composite materials could promote the mineralization and sealing of dentin tubules by releasing active ions, buffer pH 4.5 (a value close to the pH in the dental plaque environment) to pH 6.6-7.1 (values close to the pH in human saliva) through ion exchange, and exert antibacterial effects by targeting Streptococcus mutans and exerting oxidase like and peroxidase like activities to produce reactive oxygen species (ROS). The in vivo animal study showed that daily cleaning teeth using VMT/ACP/Dextran composite nanosheets could effectively reduce the incidence rate and severity of dental caries in rats. Taking together, the developed VMT/ACP/Dextran composite nanosheets, which integrated the excellent properties of VMT, ACP and dextran, can effectively prevent dental caries through a combination of factors such as buffering acids, antibacterial properties, and promoting calcification, and may be used as an active ingredient for daily oral hygiene or filling materials to prevent and treat dental caries.
Asunto(s)
Antibacterianos , Fosfatos de Calcio , Caries Dental , Dentina , Dextranos , Streptococcus mutans , Caries Dental/prevención & control , Caries Dental/microbiología , Dextranos/química , Dextranos/farmacología , Animales , Antibacterianos/farmacología , Antibacterianos/química , Concentración de Iones de Hidrógeno , Fosfatos de Calcio/química , Fosfatos de Calcio/farmacología , Streptococcus mutans/efectos de los fármacos , Dentina/química , Dentina/efectos de los fármacos , Ratas , Nanoestructuras/química , Humanos , Masculino , Ratas Sprague-Dawley , Especies Reactivas de Oxígeno/metabolismoRESUMEN
Porous poly (lactic-co-glycolic acid)/ß-tricalcium phosphate/Icaritin (PLGA/ß-TCP/ICT, PTI) scaffold is a tissue engineering scaffold based on PLGA/ß-TCP (PT) containing Icaritin, the main active ingredient of the Chinese medicine Epimedium. Due to its excellent mechanical properties and osteogenic effect, PTI scaffold has the potential to promote bone defect repair. However, the release of ICT from the scaffolds is difficult to control. In this study, we constructed Ti3C2Tx@PLGA/ICT microspheres (TIM) and evaluated their characterization as well as ICT release under near-infrared (NIR) irradiation. We utilized TIM to modify the PT scaffold and performed biological experiments. First, we cultured rat bone marrow mesenchymal stem cells on the scaffold to assess biocompatibility and osteogenic potential under on-demand NIR irradiation. Subsequently, to evaluate the osteogenic properties of TIM-modified scaffoldin vivo, the scaffold was implanted into a femoral condyle defect model. TIM have excellent drug-loading capacity and encapsulation efficiency for ICT, and the incorporation of Ti3C2Txendows TIM with photothermal conversion capability. Under 0.90 W cm-2NIR irradiation, the temperature of TIM maintained at 42.0 ± 0.5 °C and the release of ICT was accelerated. Furthermore, while retaining its original properties, the TIM-modified scaffold was biocompatible and could promote cell proliferation, osteogenic differentiation, and biomineralizationin vitro, as well as the osteogenesis and osseointegrationin vivo, and its effect was further enhanced through the modulation of ICT release under NIR irradiation. In summary, TIM-modified scaffold has the potential to be applied in bone defects repairing.