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1.
In Vitro Cell Dev Biol Anim ; 60(4): 343-353, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38504085

RESUMEN

MicroRNAs (miRNAs) play an important role in articular cartilage damage in osteoarthritis (OA). However, the biological role of miRNAs in the chondrogenic differentiation of bone marrow mesenchymal stem cell (BMSC) remains largely unclear. Rabbit bone marrow mesenchymal stem cells (rBMSCs) were isolated, cultured, and identified. Afterwards, rBMSCs were induced to chondrogenic differentiation, examined by Alcian Blue staining. Differentially expressed miRNAs were identified in rBMSCs between induced and non-induced groups by miRNA sequencing analysis, part of which was validated via PCR assay. Cell viability and apoptosis were assessed by CCK-8 assay and Hoechst staining. Saffron O staining was utilized to assess chondrocyte hyperplasia. The expression of specific chondrogenic markers, including COL2A1, SOX9, Runx2, MMP-13, Aggrecan, and BMP-2, were measured at mRNA and protein levels. The association between beta-transducin repeat containing E3 ubiquitin protein ligase (BTRC) and miR-10a-5p in the miRNA family from rabbit (ocu-miR-10a-5p) was determined by luciferase reporter assay. A total of 76 differentially expressed miRNAs, including 52 downregulated and 24 upregulated miRNAs, were identified in rBMSCs from the induced group. Inhibition of ocu-miR-10a-5p suppressed rBMSC viability and chondrogenic differentiation, as well as downregulated the expression of ß-catenin, SOX9, COL2A1, MMP-13, and Runx2. BTRC was predicted and confirmed as a target of ocu-miR-10a-5p. Overexpression of BTRC rescued the promoting impacts of overexpressed ocu-miR-10a-5p on chondrogenic differentiation of rBMSCs and ß-catenin expression. Taken together, our data suggested that ocu-miR-10a-5p facilitated rabbit BMSC survival and chondrogenic differentiation by activating Wnt/ß-catenin signaling through BTRC.


Asunto(s)
Diferenciación Celular , Condrogénesis , Células Madre Mesenquimatosas , MicroARNs , Vía de Señalización Wnt , Animales , Conejos , MicroARNs/genética , MicroARNs/metabolismo , Células Madre Mesenquimatosas/metabolismo , Células Madre Mesenquimatosas/citología , Diferenciación Celular/genética , Condrogénesis/genética , Vía de Señalización Wnt/genética , Condrocitos/metabolismo , Condrocitos/citología , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina-Proteína Ligasas/genética , Apoptosis/genética , Supervivencia Celular , beta Catenina/metabolismo , beta Catenina/genética , Secuencia de Bases , Regulación de la Expresión Génica
2.
Anal Cell Pathol (Amst) ; 2024: 1083143, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38946863

RESUMEN

Objectives: Osteochondral defects (OCDs) are localized areas of damaged cartilage and underlying subchondral bone that can produce pain and seriously impair joint function. Literature reports indicated that icariin (ICA) has the effect of promoting cartilage repair. However, its mechanism remains unclear. Here, we explored the effects of icariin and extracellular vesicles (EVs) from rabbit synovial-derived mesenchymal stem cells (rSMSCs) on repairing of OCDs. Materials and Methods: Rabbit primary genicular chondrocytes (rPGCs), knee skeletal muscle cells (rSMCKs), and rSMSCs, and extracellular vesicles derived from the latter two cells (rSMCK-EVs and rSMSC-EVs) were isolated and identified. The rPGCs were stimulated with ICA, rSMSC-EVs either separately or in combination. The rSMCK-EVs were used as a control. After stimulation, chondrogenic-related markers were analyzed by quantitative RT-PCR and western blotting. Cell proliferation was determined by the CCK-8 assay. The preventative effects of ICA and SMSC-EVs in vivo were determined by H&E and toluidine blue staining. Immunohistochemical analyses were performed to evaluate the levels of COL2A1 and ß-catenin in vivo. Results. In vitro, the proliferation of rPGCs was markedly increased by ICA treatment in a dose-dependent manner. When compared with ICA or rSMSC-EVs treatment alone, combined treatment with ICA and SMSC-EVs produced stronger stimulative effects on cell proliferation. Moreover, combined treatment with ICA and rSMSC-EVs promoted the expression of chondrogenic-related gene, including COL2A1, SOX-9, and RUNX2, which may be via the activation of the Wnt/ß-catenin pathway. In vivo, combined treatment with rSMSC-EVs and ICA promoted cartilage repair in joint bone defects. Results also showed that ICA or rSMSC-EVs both promoted the COL2A1 and ß-catenin protein accumulation in articular cartilage, and that was further enhanced by combined treatment with rSMSC-EVs and ICA. Conclusion: Our findings highlight the promising potential of using combined treatment with ICA and rSMSC-EVs for promoting osteochondral repair.


Asunto(s)
Condrocitos , Condrogénesis , Vesículas Extracelulares , Flavonoides , Células Madre Mesenquimatosas , Membrana Sinovial , Vía de Señalización Wnt , Animales , Conejos , Flavonoides/farmacología , Células Madre Mesenquimatosas/metabolismo , Células Madre Mesenquimatosas/citología , Vía de Señalización Wnt/efectos de los fármacos , Vesículas Extracelulares/metabolismo , Condrocitos/metabolismo , Condrocitos/efectos de los fármacos , Membrana Sinovial/metabolismo , Membrana Sinovial/citología , Condrogénesis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , beta Catenina/metabolismo , Cartílago Articular/metabolismo , Cartílago Articular/efectos de los fármacos
3.
Mater Horiz ; 10(11): 5202-5213, 2023 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-37725381

RESUMEN

The merging of traditional microwave absorbing materials with metamaterials holds significant potential for enhancing microwave absorber performance. To unlock this potential, a unified paradigm is urgently required. We have successfully established such a paradigm, focusing on regulating effective electromagnetic parameters and interfacial forms across microscopic, mesoscopic, and macroscopic scales. Building upon this foundation, we introduce an active co-design methodology for jointly optimizing full-scale structures and the concept of "full-scale microwave absorbers" (FSMAs). Under this guidance, performance improvements can be achieved efficiently, leading to crucial breakthroughs. For demonstration, we present a case study designing ultra-thin miniaturized FSMAs capable of ultra-broadband and low-frequency absorption. Simulation results show absorptivity exceeding 90% in the 2-28 GHz range, with absorptivity surpassing 85% and 74% in the 1.5-2 GHz and 1-1.5 GHz ranges, respectively. Additionally, the total thickness and macro period are only 5 mm, roughly equivalent to 0.033 wavelengths of the lowest operating frequency. Most importantly, we have broken the Rozanov limit, with experimental results further validating this design. This work significantly enhances our understanding of microwave absorption and offers a shortcut for pursuing improved performances and breakthroughs.

4.
Ann Transl Med ; 10(12): 691, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35845525

RESUMEN

Background: Icariin (ICA) has been widely used in the treatment of osteoporosis. However, the potential mechanism of its critical role in repairing knee cartilage damage still needs to be further clarified. Methods: First, rabbit bone marrow mesenchymal stem cells (BMSCs) were isolated, cultured, and identified. Subsequently, BMSCs were treated with different concentrations of ICA. Cell Counting Kit 8 (CCK-8) and 5-ethynyl-2'-deoxyuridine (EdU) were used to evaluate the cell proliferation in each group. Alcian Blue staining, immunofluorescence, and western blotting were used to evaluate the ability of BMSCs to differentiate cartilage. In addition, a rabbit knee cartilage injury model was established. Evaluation of cartilage defects in each group was performed according to the classification system outlined by the International Cartilage Repair Society (ICRS). Hematoxylin and eosin (HE), Alcian Blue, and immunohistochemistry were used to analyze the pathological status of knee cartilage. Results: In vitro, the results showed that ICA promoted the cartilage differentiation of BMSCs as well as cell proliferation. In addition, ICA promoted the expression of type II collagen (COL2A1), aggrecan, and bone morphogenetic protein 2 (BMP2) in BMSCs, while BMP-Smad inhibitor (Noggin) reversed the repair effect of ICA on BMSCs. In vivo, our results showed that the ICRS score of the BMSC and ICA treatment group was higher. Moreover, BMSC and ICA treatment promoted the proliferation of chondrocytes and repaired the cartilage-like tissue on the surface of cartilage defect. Conclusions: The combined application of ICA and BMSCs can repair rabbit knee cartilage injury by regulating the BMP/Smads pathway, indicating that ICA and BMSCs may be a viable clinical treatment strategy for knee cartilage damage.

5.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 27(4): 924-8, 2010 Aug.
Artículo en Zh | MEDLINE | ID: mdl-20842873

RESUMEN

Multiple sequence alignment is one of the basic techniques in bioinformatics, and it plays a vital role in structure modeling, functional site prediction, and phylogenetic analysis. In this paper, we review the methodologies and recent advances in the multiple protein sequence alignment, e.g., speeding up the calculation of distances among sequences and employing the iterative refinement and consistency-based scoring function, with emphasis on the use of additional sequence and structural information for improving alignment quality.


Asunto(s)
Algoritmos , Proteínas/química , Alineación de Secuencia/métodos , Análisis de Secuencia de Proteína/métodos
6.
Life Sci ; 253: 117730, 2020 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-32348838

RESUMEN

Stem cell therapy is widely employed in treating osteoarthritis (OA), and bone marrow-derived mesenchymal stem cells (BMSCs) has gradually become the most attractive new method for treating OA due to the benefit for cartilage tissue repair. However, the apoptosis in the neural stem cell transplantation severely decreases repairing efficacy. Icariin has been reported to exert multiple effects on BMSCs, including its proliferation, osteogenic, and chondrogenic differentiation. However, its effects on the injury induced by oxygen, glucose and serum deprivation (OGD) remains unknown. We prospectively investigated the role of ICA on rabbit BMSCs under conditions of OGD. Firstly, BMSCs were cultured under conditions of OGD, ICA relieved OGD-induced cell damage by promoting cell proliferation and suppressing apoptosis. Secondly, Markers of endoplasmic reticulum stress (ERs), ER stress IRE-1 pathway, and autophagy were both inhibited by ICA via inhibition of phosphor-extracellular regulated protein kinases (p-ERKs), p-P38, p-c-Jun N-terminal kinase (p-JNK) or si-MAPK. Finally, decrease of ERs marker levels enhanced protective effect of ICA against OGD-induced injury by limiting apoptosis and autophagy. Moreover, an autophagy inhibitor (3-methyladenine: 3-MA) contributed to a synergistic effect in conjunction with ICA, in promoting cell proliferation, suggesting that ICA exerts anti-ERs and anti-autophagy effects in OGD-treated BMSCs. Therefore, ICA protected rabbit BMSCs from OGD-induced apoptosis through inhibitory regulation of ERs-mediated autophagy related to the MAPK signaling pathway, which provided insights for a potential therapeutic strategy in OA.


Asunto(s)
Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Estrés del Retículo Endoplásmico/efectos de los fármacos , Flavonoides/farmacología , Células Madre Mesenquimatosas/metabolismo , Animales , Proliferación Celular/efectos de los fármacos , Glucosa/deficiencia , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Oxígeno/metabolismo , Estudios Prospectivos , Conejos , Transducción de Señal/efectos de los fármacos
7.
J Colloid Interface Sci ; 318(2): 202-9, 2008 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-18061603

RESUMEN

The scaling relationship between the storage modulus (G(')) and the volume fraction of solids (Phi) in fat crystal networks has been explained by the fractal model developed by our group. However, many experimental results and simulation studies suggest that the stress distribution within a colloidal network is dramatically heterogeneous, which means that a small part of the network carries most of the stress, while the other part of the network does not contribute much to the elastic properties of the system. This concept was introduced into a modified fractal model. The volume fraction of solids term (Phi) in the original fractal model was replaced by Phi(e), the effective volume fraction of solids, in the modified fractal model, which represents the volume fraction of stress-carrying solids. A proposed expression for Phi(e) is given and a modified expression for the scaling relationship between G(') and Phi is obtained. The modified fractal model fits the experiment data well and successfully explains the sometimes observed nonlinear log-log behavior between the storage modulus of colloidal networks and their volume fraction of solids.


Asunto(s)
Coloides/química , Grasas/química , Ácidos Grasos Monoinsaturados/química , Leche/química , Modelos Químicos , Animales , Cristalización , Elasticidad , Modelos Moleculares , Estructura Molecular , Aceite de Brassica napus , Reología , Estrés Mecánico , Temperatura
8.
Sci Rep ; 7(1): 9462, 2017 08 25.
Artículo en Inglés | MEDLINE | ID: mdl-28842636

RESUMEN

Lotus roots-like NiO/NiCo2O4 hybrids derived from Metal-organic frameworks (MOFs) are fabricated for the first time by using flake NiCo-MOF precursors as reactant templates. It was found that a thin sample consisting of 60 wt % NiO/NiCo2O4 hybrids in the wax matrix exhibited an effective microwave absorption bandwidth of 4.2 GHz at the thickness of 1.6 mm. The highest reflection loss of -47 dB was observed at 13.4 GHz for a sample with a thickness of 1.7 mm. Results obtained in this study indicate that hybrids of NiO and NiCo2O4 are promising microwave absorbing materials with adjustable permittivity, which can exhibit broad effective absorption bandwidth at low filler loading and thin thickness.

9.
Sci Rep ; 7: 44399, 2017 03 10.
Artículo en Inglés | MEDLINE | ID: mdl-28281690

RESUMEN

The demand for high efficiency intermediate band (IB) solar cells is driving efforts in producing high quality IB photovoltaic materials. Here, we demonstrate ZnTe:O highly mismatched alloys synthesized by high dose ion implantation and pulsed laser melting exhibiting optically active IB states and efficient sub-gap photoresponse, as well as investigate the effect of pulsed laser melting on the structural and optical recovery in detail. The structural evolution and vibrational dynamics indicates a significant structural recovery of ZnTe:O alloys by liquid phase epitaxy during pulsed laser melting process, but laser irradiation also aggravates the segregation of Te in ZnTe:O alloys. A distinct intermediate band located at 1.8 eV above valence band is optically activated as evidenced by photoluminescence, absorption and photoresponse characteristics. The carrier dynamics indicates that carriers in the IB electronic states have a relatively long lifetime, which is beneficial for the fast separation of carriers excited by photons with sub-gap energy and thus the improved overall conversion efficiency. The reproducible capability of implantation and laser annealing at selective area enable the realization of high efficient lateral junction solar cells, which can ensure extreme light trapping and efficient charge separation.

10.
Adv Colloid Interface Sci ; 128-130: 257-65, 2006 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-17217908

RESUMEN

This paper highlights the most recent progress in the quantitative study on the microstructure and the rheological properties of colloidal fat crystal networks. Several physical models describing the structural hierarchy of the colloidal fat crystal networks are reviewed here, with particular emphasis on fractal model, which can be used to explain the scaling behavior of fat crystal networks. The concept of the fractal dimension has been extensively used in the quantitative study of the microstructure of fat crystal networks and other colloidal networks; however, the relationship between the fractal dimension value and microstructural characteristics remains somewhat nebulous. Recent computer simulation work from our laboratory will be presented relating simulated microstructural features to values of particular measure of fractality including the box-counting, particle counting and Fourier-transform fractal dimensions.

11.
ACS Appl Mater Interfaces ; 7(8): 4744-50, 2015 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-25664491

RESUMEN

In this paper, we designed a novel core-shell composite for microwave absorption application in which the α-Fe2O3 and the porous CoFe2O4 nanospheres served as the core and shell, respectively. Interestingly, during the solvothermal process, the solvent ratio (V) of PEG-200 to distilled water played a key role in the morphology of α-Fe2O3 for which irregular flake, coin-like, and thinner coin-like forms of α-Fe2O3 can be produced with the ratios of 1:7, 1:3, and 1:1, respectively. The porous 70 nm diameter CoFe2O4 nanospheres were generated as the shell of α-Fe2O3. It should be noted that the CoFe2O4 coating layer did not damage the original shape of α-Fe2O3. As compared with the uncoated α-Fe2O3, the Fe2O3@CoFe2O4 composites exhibited improved microwave absorption performance over the tested frequency range (2-18 GHz). In particular, the optimal reflection loss value of the flake-like composite can reach -60 dB at 16.5 GHz with a thin coating thickness of 2 mm. Furthermore, the frequency bandwidth corresponding to the RLmin value below -10 dB was up to 5 GHz (13-18 GHz). The enhanced microwave absorption properties of these composites may originate from the strong electron polarization effect (i.e., the electron polarization between Fe and Co) and the electromagnetic wave scattering on this special porous core-shell structure. In addition, the synergy effect between α-Fe2O3 and CoFe2O4 also favored balancing the electromagnetic parameters. Our results provided a promising approach for preparing an absorbent with good absorption intensity and a broad frequency that was lightweight.

12.
Sci Rep ; 5: 18249, 2015 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-26659124

RESUMEN

The shell on the nano-magnetic absorber can prevent oxidation, which is very important for its practical utilization. Generally, the nonmagnetic shell will decrease the integral magnetic loss and thus weaken the electromagnetic absorption. However, maintaining the original absorption properties of the magnetic core is a major challenge. Here, we designed novel and facile CoxFey@C composites by reducing CoxFe3-xO4@phenolic resin (x = 1, 0.5 and 0.25). High saturation magnetization value (Ms) of CoxFey particle, as a core, shows the interesting magnetic loss ability. Meanwhile, the carbon shell may increase the integral dielectric loss. The resulting composite shows excellent electromagnetic absorption properties. For example, at a coating thickness of 2 mm, the RLmin value can reach to -23 dB with an effective frequency range of 7 GHz (11-18 GHz). The mechanisms of the improved microwave absorption properties are discussed.

13.
Evol Bioinform Online ; 10: 11-6, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24526831

RESUMEN

To discover relationships and associations rapidly in large-scale datasets, we propose a cross-platform tool for the rapid computation of the maximal information coefficient based on parallel computing methods. Through parallel processing, the provided tool can effectively analyze large-scale biological datasets with a markedly reduced computing time. The experimental results show that the proposed tool is notably fast, and is able to perform an all-pairs analysis of a large biological dataset using a normal computer. The source code and guidelines can be downloaded from https://github.com/HelloWorldCN/RapidMic.

14.
Comput Biol Chem ; 34(1): 63-70, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20042369

RESUMEN

Serial analysis of gene expression (SAGE) is a powerful tool to obtain gene expression profiles. Clustering analysis is a valuable technique for analyzing SAGE data. In this paper, we propose an adaptive clustering method for SAGE data analysis, namely, PoissonAPS. The method incorporates a novel clustering algorithm, Affinity Propagation (AP). While AP algorithm has demonstrated good performance on many different data sets, it also faces several limitations. PoissonAPS overcomes the limitations of AP using the clustering validation measure as a cost function of merging and splitting, and as a result, it can automatically cluster SAGE data without user-specified parameters. We evaluated PoissonAPS and compared its performance with other methods on several real life SAGE datasets. The experimental results show that PoissonAPS can produce meaningful and interpretable clusters for SAGE data.


Asunto(s)
Perfilación de la Expresión Génica/métodos , Modelos Genéticos , Modelos Estadísticos , Neoplasias/genética , Algoritmos , Animales , Análisis por Conglomerados , Bases de Datos Genéticas , Biblioteca de Genes , Humanos , Ratones , Distribución de Poisson , ARN Mensajero/genética , Retina/metabolismo , Programas Informáticos
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