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1.
Small ; 19(19): e2206960, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36772909

RESUMEN

Integrating a biomimetic extracellular matrix to improve the microenvironment of 3D printing scaffolds is an emerging strategy for bone substitute design. Here, a "soft-hard" bone implant (BM-g-DPCL) consisting of a bioactive matrix chemically integrated on a polydopamine (PDA)-coated porous gradient scaffold by polyphenol groups is constructed. The PDA-coated "hard" scaffolds promoted Ca2+ chelation and mineral deposition; the "soft" bioactive matrix is beneficial to the migration, proliferation, and osteogenic differentiation of stem cells in vitro, accelerated endogenous stem cell recruitment, and initiated rapid angiogenesis in vivo. The results of the rabbit cranial defect model (Φ = 10 mm) confirmed that BM-g-DPCL promoted the integration between bone tissue and implant and induced the deposition of bone matrix. Proteomics confirmed that cytokine adhesion, biomineralization, rapid vascularization, and extracellular matrix formation are major factors that accelerate bone defect healing. This strategy of highly chemically bonded soft-hard components guided the construction of the bioactive regenerative scaffold.


Asunto(s)
Osteogénesis , Andamios del Tejido , Animales , Conejos , Porosidad , Biomimética , Remodelación Ósea
2.
Molecules ; 28(6)2023 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-36985720

RESUMEN

As a low energy consumption, simple operation and environmentally friendly separation method, membrane separation has attracted extensive attention. Therefore, researchers have designed and synthesized various types of separation membrane, such as metal organic framework (MOF), covalent organic framework (COF), polymer of intrinsic micro-porosity (PIM) and mixed matrix membranes. Some substituted polyacetylenes have distorted structures and formed micropores due to the existence of rigid main chains and substituted side groups, which can be applied to the field of membrane separation. This article mainly introduces the development and application of substituted polyacetylenes in gas separation and liquid separation based on membrane technology.

3.
Molecules ; 28(1)2022 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-36615223

RESUMEN

Poly(4-trimethylsilyl diphenyl acetylene) (PTMSDPA) has strong fluorescence emission, but its application is limited by the effect of aggregation-caused quenching (ACQ). Copolymerization is a commonly used method to adjust the properties of polymers. Through the copolymerization of 4-trimethylsilyl diphenyl acetylene and 1-trimethylsilyl-1-propyne (TMSP), we successfully realized the conversion of PTMSDPA from ACQ to aggregation-induced emission (AIE) and aggregation-induced emission enhancement (AEE). By controlling the monomer feeding ratio and with the increase of the content of TMSDPA inserted into the copolymer, the emission peak was red-shifted, and a series of copolymers of poly(TMSDPA-co-TMSP) that emit blue-purple to orange-red light was obtained, and the feasibility of the application in explosive detection was verified. With picric acid (PA) as a model explosive, a super-quenching process has been observed, and the quenching constant (KSV) calculated from the Stern-Volmer equation is 24,000 M-1, which means that the polymer is potentially used for explosive detection.

4.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 52(3): 380-386, 2021 May.
Artículo en Zh | MEDLINE | ID: mdl-34018354

RESUMEN

In regenerative medicine, stem cell therapy is an effective strategy for tissue regeneration and has a positive therapeutic effect on the regeneration and repair of defective tissues. In recent years, a series of studies have shown that the positive effects of stem cell therapy are mediated by exosomes released by the paracrine action of mesenchymal stem cells. Researchers have thus proposed a novel treatment strategy to use stem-cell-derived exosomes alone for tissue regeneration and repair, and affirmed through studies that the effects achieved were comparable to those of stem-cell-based therapies. Therefore, as a promising treatment strategy, exosome-based tissue regeneration treatment measures have been extensively studied. In this review, we discussed the latest knowledge of exosomes and the research progress in the regeneration and repair of related connective tissues, including the regeneration of bones, cartilage, skin, spinal cord and tendons, and briefly discussed the corresponding mechanisms. In addition, the challenges and prospects of tissue regeneration and repair based on mesenchymal stem cell exosomes were discussed.


Asunto(s)
Exosomas , Células Madre Mesenquimatosas , Medicina Regenerativa , Tendones , Cicatrización de Heridas
5.
J Gene Med ; 22(2): e3152, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31830337

RESUMEN

BACKGROUND: Troponin T1 (TNNT1) is a subunit of troponin that has been linked to neuromuscular disorder. Recently, it was reported that TNNT1 facilitates the proliferation of breast cancer cells. Interestingly, Cancer Genome Atlas data indicate that its overexpression is associated with an unfavorable prognosis of colorectal cancer (CRC) patients. The present study aimed to explore the expression, function and mechanism of dysregulation of TNNT1 in CRC. METHODS: Immunohistochemical staining and a real-time polymerase chain reaction were used to compare the expression level of TNNT1 in CRC tissues and adjacent tissues. Western blotting was used to detect the expression of TNNT1 in cell lines. Kaplan-Meier analysis and a chi-squared test were applied to evaluate the potential of TNNT1 to function as a cancer biomarker. RNA interference was used to inhibit TNNT1 expression in CRC cells, followed by detection of cell proliferation, apoptosis, migration and invasion. A luciferase reporter gene assay was used to determine the regulatory relationship between miR-873 and TNNT1. RESULTS: In the present study, we found that TNNT1 was significantly up-regulated in CRC samples and cell lines. The up-regulation of TNNT1 was also associated with several clinicopathologic features, and its high expression was correlated with an unfavorable prognosis of the patients. Knockdown of TNNT1 markedly arrested proliferation, migration and invasion, whereas it also promoted apoptosis. TNNT1 was identified as a target gene of miR-873, and there was a negative correlation among CRC samples. CONCLUSIONS: In conclusion, we have demonstrated that TNNT1, regulated by miR-873, is an oncogene of CRC associated with patient prognosis.


Asunto(s)
Neoplasias Colorrectales/patología , MicroARNs/genética , Troponina T/metabolismo , Apoptosis , Biomarcadores de Tumor/genética , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Neoplasias Colorrectales/genética , Progresión de la Enfermedad , Femenino , Regulación Neoplásica de la Expresión Génica , Células HT29 , Humanos , Masculino , Invasividad Neoplásica , Pronóstico , Troponina T/genética
6.
Langmuir ; 36(39): 11589-11599, 2020 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-32894945

RESUMEN

Catalytic hydrogenations represent fundamental processes and allow for atom-efficient and clean functional group transformations for the production of chemical intermediates and fine chemicals in chemical industry. Herein, the Ru/CoO nanocomposites have been constructed and applied as nanocatalysts for the hydrogenation of phenols and furfurals into the corresponding cyclohexanols and tetrahydrofurfuryl alcohols, respectively. The functionalized ionic liquid acted not only as a ligand for stabilizing the Ru/CoO nanocatalyst but also as a thermoregulated agent. The as-obtained nanocatalyst showed superior activity, and it could be conveniently recovered via the thermoregulating phase separation. In six recycle experiments, the catalysts maintained excellent performance. It was observed that the catalytic performance highly hinged on the molar ratio of Ru to Co in the nanocatalyst. The catalyst characterization was carried out by high-resolution transmission electron microscopy (HRTEM), high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), X-ray photoelectron spectroscopy, X-ray diffraction, high-resolution mass spectrometry, Fourier transform infrared, nuclear magnetic resonance, and UV-vis. Especially, the characterization by HRTEM and HAADF-STEM images of the nanocatalyst demonstrated that Ru(0) and Co(II) species were distributed uniformly and the Ru and Co(II) species were close to each other. However, Co(0) was generated and an electronic transfer from Co to Ru species could occur under the hydrogenation conditions. The 13C NMR characterization indicated further that Co(II) sites were mainly responsible for phenol adsorption. Meanwhile, the adjacent electron-rich Ru(0) sites can promote H2 dissociation and favor for the sequential hydrogenation.

7.
Chemistry ; 25(16): 4206-4217, 2019 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-30690807

RESUMEN

We present here a new class of niobium oxoclusters that are stabilized effectively by carboxylate ionic liquids. These functionalized ILs are designated as [TBA][LA], [TBA][PA], and [TBA][HPA] in this work, in which TBA represents tetrabutylammonium and LA, PA, and HPA refer to lactate, propionate, 3-hydroxypropionate anions, respectively. The as-synthesized Nb oxoclusters have been characterized by use of elemental analysis, NMR, IR, XRD, TGA, HRTEM. It was found that [TBA][LA]-stabilized Nb oxoclusters (Nb-OC@[TBA][LA]) are uniformly dispersed with an average particle size of 2-3 nm and afforded exceptionally high catalytic activity for the selective oxidation of various thioethers. The turnover number with Nb-OC@[TBA][LA] catalyst was over 56 000 at catalyst loading as low as 0.0033 mol % (1 ppm). Meantime, the catalyst also showed the high activity for the epoxidation of olefins and allylic alcohols by using only 0.065 mol % of catalyst (50 ppm). The characterization of 93 Nb NMR spectra revealed that the Nb oxoclusters underwent structural transformation in the presence of H2 O2 but regenerated to their initial state at the end of the reaction. In particular, the highly dispersed Nb oxoclusters can absorb a large amount of polar organic solvents and thus were swollen greatly, which exhibited "pseudo" liquid phase behavior, and enabled the substrate molecules to be highly accessible to the catalytic center of Nb oxocluster units.

8.
Drug Dev Ind Pharm ; 43(7): 1197-1204, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28300426

RESUMEN

BACKGROUND: Dioscin has shown cytotoxicity against cancer cells, but its poor solubility and stability have limited its clinical application. In this study, we designed mixed micelles composed of TPGS and Soluplus® copolymers entrapping the poorly soluble anticancer drug dioscin. METHOD: In order to improve the aqueous solubility and bioactivity of dioscin, TPGS/Soluplus® mixed micelles with an optimal ratio were prepared using a thin-film hydration method, and their physicochemical properties were characterized. Cellular cytotoxicity and uptake of the dioscin-loaded TPGS/Soluplus® mixed micelles were studied in MCF-7 breast cancer cells and A2780s ovarian cancer cells. The pharmacokinetics of free dioscin and dioscin-loaded TPGS/Soluplus® mixed micelles was studied in vivo in male Sprague-Dawley rats via a single intravenous injection in the tail vein. RESULTS: The average size of the optimized mixed micelle was 67.15 nm, with 92.59% drug encapsulation efficiency and 4.63% drug loading efficiency. The in vitro release profile showed that the mixed micelles presented sustained release behavior compared to the anhydrous ethanol solution of dioscin. In vitro cytotoxicity assays were conducted on human cancer cell lines including A2780s ovarian cancer cells and MCF-7 breast cancer cells. The mixed micelles exhibited better antitumor activity compared to free dioscin against all cell lines, which may benefit from the significant increase in the cellular uptake of dioscin from mixed micelles compared to free dioscin. The pharmacokinetic study showed that the mixed micelle formulation achieved a 1.3 times longer mean residual time (MRT) in circulation and a 2.16 times larger area under the plasma concentration-time curve (AUC) than the free dioscin solution. CONCLUSION: Our results suggest that the dioscin-loaded mixed micelles developed in this study might be a potential nano drug-delivery system for cancer chemotherapy.


Asunto(s)
Antineoplásicos/administración & dosificación , Antineoplásicos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Diosgenina/análogos & derivados , Neoplasias Ováricas/tratamiento farmacológico , Poloxámero/química , Polietilenglicoles/administración & dosificación , Polivinilos/administración & dosificación , Vitamina E/administración & dosificación , Animales , Antineoplásicos/química , Línea Celular Tumoral , Diosgenina/administración & dosificación , Diosgenina/química , Diosgenina/farmacología , Femenino , Humanos , Células MCF-7 , Micelas , Polietilenglicoles/química , Polivinilos/química , Ratas Sprague-Dawley , Vitamina E/química
9.
Diabetes Metab Syndr Obes ; 17: 215-225, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38229907

RESUMEN

Introduction: To investigate the predictors of diabetic kidney disease (DKD) in type 2 diabetes mellitus (T2DM) patients and establish a nomogram model for predicting the risk of DKD. Methods: The clinical data of T2DM patients, admitted to the Endocrinology Department of Chengde Central Hospital from October 2019 to September 2020 and divided into a case group or a control group based on whether they had DKD, were collected. The predictive factors of DKD were screened by univariate and multivariate analysis, and a nomogram prediction model was constructed for the risk of DKD in T2DM. Bootstrapping was used for model validation, receiver operating characteristic (ROC) curve and GiViTI calibration curve were used for evaluating the discrimination and calibration of prediction model, and decision analysis curve (DCA) was used for evaluating the practicality of model. Results: Predictors for DKD are diabetic retinopathy (DR), hypertension, history of gout, smoking history, using insulin, elevation of body mass index (BMI), triglyceride (TG), cystatin C (Cys-C), and reduction of 25 (OH) D. The nomogram prediction model based on the above nine predictors had good representativeness (Bootstrap method: precision: 0.866, Kappa: 0.334), differentiation [the area under curve (AUC) value: 0.868], and accuracy (GiViTI-corrected curved bands, P = 0.836); the DAC curve analysis showed that the prediction model, whose threshold probability was in the range of 0.10 to 0.70, had clinical practical value. Conclusion: The risk of DKD in T2DM could be predicted accurately by DR, hypertension, history of gout, smoking history, using insulin, elevation of BMI, TG, Cys-C, and reduction of 25 (OH) D.

10.
Adv Mater ; 36(16): e2312559, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38266145

RESUMEN

Abnormal silencing of fibroblast growth factor (FGF) signaling significantly contributes to joint dysplasia and osteoarthritis (OA); However, the clinical translation of FGF18-based protein drugs is hindered by their short half-life, low delivery efficiency and the need for repeated articular injections. This study proposes a CRISPR/Cas9-based approach to effectively activate the FGF18 gene of OA chondrocytes at the genome level in vivo, using chondrocyte-affinity peptide (CAP) incorporated hybrid exosomes (CAP/FGF18-hyEXO) loaded with an FGF18-targeted gene-editing tool. Furthermore, CAP/FGF18-hyEXO are encapsulated in methacrylic anhydride-modified hyaluronic (HAMA) hydrogel microspheres via microfluidics and photopolymerization to create an injectable microgel system (CAP/FGF18-hyEXO@HMs) with self-renewable hydration layers to provide persistent lubrication in response to frictional wear. Together, the injectable CAP/FGF18-hyEXO@HMs, combined with in vivo FGF18 gene editing and continuous lubrication, have demonstrated their capacity to synergistically promote cartilage regeneration, decrease inflammation, and prevent ECM degradation both in vitro and in vivo, holding great potential for clinical translation.


Asunto(s)
Cartílago Articular , Exosomas , Microgeles , Osteoartritis , Humanos , Condrocitos , Lubrificación , Exosomas/metabolismo , Edición Génica , Cartílago Articular/metabolismo , Factores de Crecimiento de Fibroblastos/genética , Factores de Crecimiento de Fibroblastos/metabolismo , Factores de Crecimiento de Fibroblastos/uso terapéutico , Osteoartritis/metabolismo
11.
J Mater Chem B ; 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38904349

RESUMEN

The management of chronic infected wounds poses significant challenges due to frequent bacterial infections, high concentrations of reactive oxygen species, abnormal immune regulation, and impaired angiogenesis. This study introduces a novel, microenvironment-responsive, dual dynamic, and covalently bonded hydrogel, termed OHA-P-TA/G/Mg2+. It is derived from the reaction of tannic acid (TA) with phenylboronic acids (PBA), which are grafted onto oxidized hyaluronic acid (OHA-P-TA), combined with GelMA (G) via a Schiff base and chemical bonds, along with the incorporation of Mg2+. This hydrogel exhibits pH and ROS dual-responsiveness, demonstrating effective antibacterial capacity, antioxidant ability, and the anti-inflammatory ability under distinct acidic and oxidative microenvironments. Furthermore, the release of Mg2+ from the TA-Mg2+ network (TA@Mg2+) promotes the transformation of pro-inflammatory M1 phenotype macrophages to anti-inflammatory M2 phenotype, showing a microenvironment-responsive response. Finally, in vivo results indicate that the OHA-P-TA/G/Mg2+ hydrogel enhances epithelial regeneration, collagen deposition, and neovascularization, showing great potential as an effective dressing for infected wound repair.

12.
Protein Pept Lett ; 30(5): 427-438, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36918782

RESUMEN

BACKGROUND: Neurensin-2 (NRSN2) is reported to be associated with the progression of many tumors. This work aimed at investigating the biological function and prognostic significance of NRSN2 in gastric cancer (GC). METHODS: NRSN2 expression in various cancer tissue was analyzed by the TIMER database. NRSN2 expression in GC tissue samples of different groups was analyzed by the UALCAN database. The survival analysis was performed with the Kaplan-Meier database. NRSN2 expression in GC tissues and cell lines was measured by qRT-PCR and Western blot. CCK-8, Transwell and scratch healing assays were conducted to detect the proliferative, migrative and invasive capabilities of GC cells, respectively. The LinkedOmics database and StarBase database were utilized to analyze the related genes with NRSN2 in GC. The association of NRSN2 expression with tumor immune infiltrating cells and molecular markers of immune cells was investigated with the TIMER database. RESULTS: NRSN2 expression was up-regulated in GC tissues, which was correlated with GC tumor grade, lymph node metastasis, and TP53 mutation. The prognosis of GC patients with high NRSN2 expression was worse than those of the patients with low NRSN2 expression. NRSN2 expression was also associated with the TNM stage, and Lauren subtype of GC patients. NRSN2 overexpression promoted the growth, migration and invasion of GC cells lines; knocking down NRSN2 worked oppositely. NRSN2 expression in GC was associated with Wnt, p53, and NOD-like receptor signaling pathways. NRSN2 expression was also significantly associated with the infiltration of CD8+ T cells, CD4+ T cells, macrophages, neutrophils, and dendritic cells in the GC microenvironment. CONCLUSION: NRSN2 expression in GC tissues is up-regulated, which correlates with a poor prognosis and immune cell infiltration of GC patients. NRSN2 facilitates the growth and aggressiveness of GC cells, implying that it may be a diagnostic biomarker and therapy target for GC.


Asunto(s)
Neoplasias Gástricas , Humanos , Neoplasias Gástricas/genética , Pronóstico , Linfocitos T CD8-positivos/metabolismo , Linfocitos T CD8-positivos/patología , Transducción de Señal , Microambiente Tumoral
13.
Pathol Res Pract ; 241: 154234, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36459833

RESUMEN

BACKGROUND: Colorectal cancer (CRC) is a common malignancy, and radioresistance limits the effectiveness of radiotherapy for rectal cancer. This study is performed to investigate the role and regulatory mechanism of Potassium Voltage-Gated Channel Subfamily E Regulatory Subunit 4 (KCNE4) in the radioresistance of CRC cells. METHODS: Immunohistochemical staining results of KCNE4 in normal tissues and CRC tissues were obtained from the Human Protein Atlas (HPA) database. The UALCAN database was used for analyzing KCNE4 mRNA expression in normal tissue samples and CRC tissue samples and its relationship with tumor stage. The relationship of KCNE4 expression with prognosis was analyzed utilizing the data of GEPIA database. LinkedOmics database was searched to analyze the co-expressed gene sets of KCNE4 in CRC, and to analyze the signaling pathways related with KCNE4 in CRC. GO and KEGG enrichment analyses were carried out on the co-expressed genes of KCNE4 with DAVID database. Ionizing radiation (IR)-resistant cell lines (HCT116/IR and HT29/IR) were established; cell viability was assessed via cell counting kit-8 (CCK-8) and EdU assays, and terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assay was performed for detecting cell apoptosis. Western blotting was carried out to detect the expressions of p-p85 and p-AKT. RESULTS: KCNE4 was highly expressed in CRC tissues and linked to advanced tumor stage, lymph node metastasis and poor prognosis of CRC patients. KCNE4 overexpression promoted HCT116/IR cell proliferation and inhibited the apoptosis, while KCNE4 knockdown suppressed HT29/IR cell proliferation and facilitated the apoptosis. Furthermore, high KCNE4 expression was associated with the activation of the PI3K/AKT signal pathway. CONCLUSION: KCNE4 is associated with the clinicopathological characteristics of CRC patients, and its high expression level contributes to the radioresistance of cancer cells via activating the PI3K/AKT signal pathway.


Asunto(s)
Neoplasias Colorrectales , Canales de Potasio con Entrada de Voltaje , Humanos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Transducción de Señal , Células HCT116 , Proliferación Celular/genética , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/radioterapia , Neoplasias Colorrectales/metabolismo , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica , Canales de Potasio con Entrada de Voltaje/genética , Canales de Potasio con Entrada de Voltaje/metabolismo
14.
ACS Nano ; 17(14): 13358-13376, 2023 07 25.
Artículo en Inglés | MEDLINE | ID: mdl-37439514

RESUMEN

As chondrocytes from osteoarthritic cartilage usually exhibit aging and senescent characteristics, targeting aging chondrocytes could be a potential therapeutic strategy. In this study, exosomes derived from umbilical cord-derived mesenchymal stem cells (UCMSC-EXOs) combined with the chondrocyte-targeting capacity and controlled-release system were proposed for osteoarthritis (OA) treatment via rejuvenating aging chondrocytes. The essential functional miRNAs within UCMSC-EXOs were investigated, with the p53 signaling pathway identified as the key factor. To improve the therapeutic efficiency and retention time of UCMSC-EXOs in vivo, the exosomes (EXOs) were engineered on membranes with a designed chondrocyte-targeting polymers, and encapsulated within thiolated hyaluronic acid microgels to form a "two-phase" releasing system, which synergistically facilitated the repair of OA cartilage in a rat model. Together, this study highlighted the rejuvenating effects of UCMSC-EXOs on OA chondrocytes and the potential to combine with chondrocyte-targeting and sustained-release strategies toward a future cell-free OA treatment.


Asunto(s)
Exosomas , Células Madre Mesenquimatosas , MicroARNs , Osteoartritis , Ratas , Animales , Condrocitos/metabolismo , Exosomas/metabolismo , Preparaciones de Acción Retardada/metabolismo , Osteoartritis/terapia , MicroARNs/metabolismo , Células Madre Mesenquimatosas/metabolismo , Cordón Umbilical/metabolismo
15.
Adv Sci (Weinh) ; 10(13): e2300038, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36905235

RESUMEN

Nanostructured biomaterials that replicate natural bone architecture are expected to facilitate bone regeneration. Here, nanohydroxyapatite (nHAp) with vinyl surface modification is acquired by silicon-based coupling agent and photointegrated with methacrylic anhydride-modified gelatin to manufacture a chemically integrated 3D-printed hybrid bone scaffold (75.6 wt% solid content). This nanostructured procedure significantly increases its storage modulus by 19.43-fold (79.2 kPa) to construct a more stable mechanical structure. Furthermore, biofunctional hydrogel with biomimetic extracellular matrix is anchored onto the filament of 3D-printed hybrid scaffold (HGel-g-nHAp) by polyphenol-mediated multiple chemical reactions, which contributes to initiate early osteogenesis and angiogenesis by recruiting endogenous stem cells in situ. Significant ectopic mineral deposition is also observed in subcutaneously implanted nude mice with storage modulus enhancement of 25.3-fold after 30 days. Meanwhile, HGel-g-nHAp realizes substantial bone reconstruction in the rabbit cranial defect model, achieving 61.3% breaking load strength and 73.1% bone volume fractions in comparison to natural cranium 15 weeks after implantation. This optical integration strategy of vinyl modified nHAp provides a prospective structural design for regenerative 3D-printed bone scaffold.


Asunto(s)
Regeneración Ósea , Andamios del Tejido , Ratones , Animales , Conejos , Ratones Desnudos , Estudios Prospectivos , Andamios del Tejido/química , Impresión Tridimensional
16.
Biomed Mater ; 17(2)2022 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-35042195

RESUMEN

Due to the avascular characteristic of articular cartilage, its self-repair capacity is limited. When cartilage is damaged or forms osteoarthritis (OA), clinical treatment is necessary. However, conventional treatments, including joint replacement, microfracture, cell and drug therapies, have certain limits. Lately, the exosomes derived from mesenchymal stem cells (MSCs-EXO), which consist of complex transcription factors, proteins and targeting ligand components, have shown great therapeutic potentials. With recent advancements in various biomaterials to extend MSCs-EXO's retention time and control the release propertiesin vivo, biomaterials-assisted exosomes therapy has been soon becoming a practically powerful tool in treating OA. This review analyzes the effects of MSCs-EXO on OA inflammation, metabolism, ageing and apoptosis, and introduces the combinational systems of MSCs-EXO with biomaterials to enhance the repair, anti-inflammatory, and homeostasis regulation functions. Moreover, different types of natural or synthetic biomaterials and their applications with MSCs-EXO were also described and discussed. And finally, we presage the future perspective in the development of biomaterial-assisted exosome therapies, as well as the potential to incorporate with other treatments to enhance their therapeutic effects in OA.


Asunto(s)
Materiales Biocompatibles , Exosomas , Osteoartritis/terapia , Animales , Materiales Biocompatibles/administración & dosificación , Materiales Biocompatibles/uso terapéutico , Células Cultivadas , Humanos , Inyecciones Intraarticulares , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/citología , Ratones , Ratas
17.
Artículo en Inglés | MEDLINE | ID: mdl-35829709

RESUMEN

Facilitating cell ingrowth and biomineralized deposition inside filaments of 3DP scaffolds are an ideal bone repair strategy. Here, 3D printed PLGA/HA scaffolds with hydroxyapatite content of 50% (P5H5) and 70% (P3H7) were prepared by optimizing 3D printing inks, which exhibited good tailorability and foldability to meet clinical maneuverability. The supercritical CO2 foaming technology further endowed the filaments of P5H5 with a richer interconnected pore structure (P5H5-C). The finite element and computational fluid dynamics simulation analysis indicated that the porosification could effectively reduce the stress concentration at the filament junction and improved the overall permeability of the scaffold. The results of in vitro experiments confirmed that P5H5-C promoted the adsorption of proteins on the surface and inside of filaments, accelerated the release of Ca and P ions, and significantly upregulated osteogenesis (Col I, ALP, and OPN)- and angiogenesis (VEGF)-related gene expression. Subcutaneous ectopic osteogenesis experiments in nude mice further verified that P5H5-C facilitated cell growth inside filaments and biomineralized deposition, as well as significantly upregulated the expression of osteogenesis- and angiogenesis-related genes (Col I, ALP, OCN, and VEGF) and protein secretion (ALP, RUNX2, and VEGF). The porosification of filaments by supercritical CO2 foaming provided a new strategy for accelerating osteogenesis of 3DP implants.

18.
Nat Commun ; 13(1): 2499, 2022 05 06.
Artículo en Inglés | MEDLINE | ID: mdl-35523800

RESUMEN

Limited stem cells, poor stretchability and mismatched interface fusion have plagued the reconstruction of cranial defects by cell-free scaffolds. Here, we designed an instantly fixable and self-adaptive scaffold by dopamine-modified hyaluronic acid chelating Ca2+ of the microhydroxyapatite surface and bonding type I collagen to highly simulate the natural bony matrix. It presents a good mechanical match and interface integration by appropriate calcium chelation, and responds to external stress by flexible deformation. Meanwhile, the appropriate matrix microenvironment regulates macrophage M2 polarization and recruits endogenous stem cells. This scaffold promotes the proliferation and osteogenic differentiation of BMSCs in vitro, as well as significant ectopic mineralization and angiogenesis. Transcriptome analysis confirmed the upregulation of relevant genes and signalling pathways was associated with M2 macrophage activation, endogenous stem cell recruitment, angiogenesis and osteogenesis. Together, the scaffold realized 97 and 72% bone cover areas after 12 weeks in cranial defect models of rabbit (Φ = 9 mm) and beagle dog (Φ = 15 mm), respectively.


Asunto(s)
Células Madre Mesenquimatosas , Osteogénesis , Animales , Regeneración Ósea , Diferenciación Celular , Perros , Células Madre Mesenquimatosas/metabolismo , Conejos , Cráneo , Células Madre , Andamios del Tejido
19.
ACS Appl Mater Interfaces ; 14(18): 20591-20602, 2022 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-35500105

RESUMEN

Seeking high biological activity and osteoinductive ability has always been an urgent problem for three-dimensional-printed (3DP) bony implants. Here, a 3DP methacrylic anhydride-modified gelatin (GelMA)/hydroxyapatite (HAp) scaffold with a high solid content of 82.5% was prepared and anchored by a functionalized polyphenol hydrogel. The scaffold and hydrogel were organically integrated into a bioinspired bony implant (HGH) by phenolic hydroxyl of hyaluronan derivatives conjugating amino groups of collagen I and GelMA and further chelating calcium ions of HAp. Compared with a simplex 3DP scaffold, this freeze-dried HGH presented better water retention, delayed degradation, and mechanical stability. It could promote migration, proliferation, and osteogenic differentiation of bone marrow stem cells in vitro. One week of implantation showed that it promoted directional migration of endogenous stem cells and early osteogenesis and angiogenesis. After 15 week surgery of rabbit skull defects, the BV/TV value of HGH returned to 73% of the normal group level. This strategy provided a new research idea for bone regeneration.


Asunto(s)
Gelatina , Hidrogeles , Animales , Regeneración Ósea , Diferenciación Celular , Durapatita , Hidrogeles/farmacología , Osteogénesis , Impresión Tridimensional , Conejos , Ingeniería de Tejidos , Andamios del Tejido
20.
J Nanosci Nanotechnol ; 21(2): 886-894, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-33183420

RESUMEN

Colorectal cancer is the third most common cause of cancer-related death in the world because of its poor prognosis and many related complications. In clinical practice, lymph node metastasis is an important index to evaluate the recurrence and survival rate of patients with rectal cancer, it also the main method to determine the treatment plan of patients with rectal cancer. Nano carbon tracer can guide surgeons to clear regional lymph nodes accurately, improve the number of lymph nodes detected, and then improve the accuracy of pathological staging of rectal cancer. It has an important clinical significance in the removal of lymph nodes of middle and low rectal cancer, and provides an important basis for the development of postoperative adjuvant treatment plan. The purpose of this study is to explore the application value of this method in improving the detection rate of lymph nodes in laparoscopic colorectal cancer. According to the research results, the total number of lymphatic gland, the number of small lymphatic gland, the rate of lymph node metastasis, the number of black stained lymphatic gland and the number of lymphatic gland confirmed by pathology in the two groups were better than those in the traditional surgical treatment, which had better application value in the radical operation of colorectal cancer.


Asunto(s)
Neoplasias Colorrectales , Laparoscopía , Nanopartículas , Carbono , Neoplasias Colorrectales/cirugía , Humanos , Escisión del Ganglio Linfático , Ganglios Linfáticos/cirugía
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