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1.
Polymers (Basel) ; 15(17)2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-37688131

RESUMO

In this study, tetraethyl orthosilicate (TEOS) and methyltriethoxysilane (MTES) were used as precursors for silica, combined with the ionic liquid [BMIM-ClO4]. Lithium perchlorate was added as the lithium-ion source, and formic acid was employed as a catalyst to synthesize silica ionogel electrolytes via the sol-gel method. FT-IR and NMR identified the self-prepared ionic liquid [BMIM-ClO4], and its electrochemical window was determined using linear sweep voltammetry (LSV). The properties of the prepared silica ionogel electrolytes were further investigated through FT-IR, DSC, and 29Si MAS NMR measurements, followed by electrochemical property measurements, including conductivity, electrochemical impedance spectroscopy (EIS), LSV, and charge-discharge tests. The experimental results showed that adding methyltriethoxysilane (MTES) enhanced the mechanical strength of the silica ionogel electrolyte, simplifying its preparation process. The prepared silica ionogel electrolyte exhibited a high ionic conductivity of 1.65 × 10-3 S/cm. In the LSV test, the silica ionogel electrolyte demonstrated high electrochemical stability, withstanding over 5 V without oxidative decomposition. Finally, during the discharge-charge test, the second-cycle capacity reached 108.7 mAh/g at a discharge-charge rate of 0.2 C and a temperature of 55 °C.

2.
Cell Transplant ; 30: 9636897211054481, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34757857

RESUMO

Biological and cellular interleukin-6 (IL-6)-related therapies have been used to treat severe COVID-19 pneumonia with hyperinflammatory syndrome and acute respiratory failure, which prompted further exploration of the role of IL-6 in human umbilical cord mesenchymal stem cell (hUCMSC) therapy. Peripheral blood mononuclear cells (PBMCs) were responders cocultured with hUCMSCs or exogenous IL-6. A PBMC suppression assay was used to analyze the anti-inflammatory effects via MTT assay. The IL-6 concentration in the supernatant was measured using ELISA. The correlation between the anti-inflammatory effect of hUCMSCs and IL-6 levels and the relevant roles of IL-6 and IL-6 mRNA expression was analyzed using the MetaCore functional network constructed from gene microarray data. The location of IL-6 and IL-6 receptor (IL-6R) expression was further evaluated. We reported that hUCMSCs did not initially exert any inhibitory effect on PHA-stimulated proliferation; however, a potent inhibitory effect on PHA-stimulated proliferation was observed, and the IL-6 concentration reached approximately 1000 ng/mL after 72 hours. Exogenous 1000 ng/mL IL-6 inhibited PHA-stimulated inflammation but less so than hUCMSCs. The inhibitory effects of hUCMSCs on PHA-stimulated PBMCs disappeared after adding an IL-6 neutralizing antibody or pretreatment with tocilizumab (TCZ), an IL-6R antagonist. hUCMSCs exert excellent anti-inflammatory effects by inducing higher IL-6 levels, which is different from TCZ. High concentration of IL-6 cytokine secretion plays an important role in the anti-inflammatory effect of hUCMSC therapy. Initial hUCMSC therapy, followed by TCZ, seems to optimize the therapeutic potential to treat COVID-19-related acute respiratory distress syndrome (ARDS).


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , COVID-19/complicações , Interleucina-6/biossíntese , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/metabolismo , Síndrome do Desconforto Respiratório/terapia , SARS-CoV-2 , Anticorpos Monoclonais Humanizados/farmacologia , Anticorpos Neutralizantes/imunologia , Células Cultivadas , Técnicas de Cocultura , Terapia Combinada , DNA Complementar/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Inflamação , Interleucina-6/genética , Interleucina-6/farmacologia , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Ativação Linfocitária/efeitos dos fármacos , Fito-Hemaglutininas/farmacologia , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Receptores de Interleucina-6/antagonistas & inibidores , Receptores de Interleucina-6/biossíntese , Receptores de Interleucina-6/genética , Síndrome do Desconforto Respiratório/tratamento farmacológico , Síndrome do Desconforto Respiratório/etiologia , Cordão Umbilical/citologia
3.
Cancer Biomark ; 27(3): 377-387, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31958077

RESUMO

BACKGROUND: METCAM/MUC18 expression was increased with the malignant progression of prostate cancer and also a bona fide metastatic gene, capable of initiating and driving the metastasis of a non-metastatic human prostate cancer cell line to multiple organs. OBJECTIVE: We explored if METCAM/MUC18 was detectable in human serum and a novel biomarker to predict malignant propensity of prostate cancer. MATERIALS AND METHODS: Two antibodies were identified by Western blot analysis having the highest sensitivity and specificity to establish calibration curves from the recombinant METCAM/MUC18 proteins. They were used in ELISA and LFIA to determine the METCAM/MUC18 concentrations in serum samples from 8 normal individuals, 4 BPH patients, 1 with PIN, 6 with high-grade prostate cancer, and 2 treated cancer patients. RESULTS: Serum METCAM/MUC18 concentrations were statistically significantly higher in the patients with PIN and prostate cancer than those with BPH, the treated patients and normal individuals. The LFIA results were statistically better than ELISA and Western blot methods. Serum METCAM/MUC18 concentrations were in direct proportional to most of serum PSA concentrations.


Assuntos
Neoplasias da Próstata/sangue , Adulto , Idoso , Biomarcadores Tumorais/sangue , Western Blotting/métodos , Antígeno CD146/sangue , Progressão da Doença , Ensaio de Imunoadsorção Enzimática/métodos , Humanos , Imunoensaio/métodos , Calicreínas/sangue , Masculino , Pessoa de Meia-Idade , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/patologia
4.
Materials (Basel) ; 11(6)2018 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-29848981

RESUMO

In this study, a previously known high-affinity silica binding protein (SB) was genetically engineered to fuse with an integrin-binding peptide (RGD) to create a recombinant protein (SB-RGD). SB-RGD was successfully expressed in Escherichia coli and purified using silica beads through a simple and fast centrifugation method. A further functionality assay showed that SB-RGD bound to the silica surface with an extremely high affinity that required 2 M MgCl2 for elution. Through a single-step incubation, the purified SB-RGD proteins were noncovalently coated onto an electrospun silica nanofiber (SNF) substrate to fabricate the SNF-SB-RGD substrate. SNF-SB-RGD was characterized by a combination of scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, and immunostaining fluorescence microscopy. As PC12 cells were seeded onto the SNF-SB-RGD surface, significantly higher cell viability and longer neurite extensions were observed when compared to those on the control surfaces. These results indicated that SB-RGD could serve as a noncovalent coating biologic to support and promote neuron growth and differentiation on silica-based substrates for neuronal tissue engineering. It also provides proof of concept for the possibility to genetically engineer protein-based signaling molecules to noncovalently modify silica-based substrates as bioinspired material.

5.
Nanomaterials (Basel) ; 8(3)2018 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-29538349

RESUMO

In this study, we first synthesized a slow-degrading silica nanofiber (SNF2) through an electrospun solution with an optimized tetraethyl orthosilicate (TEOS) to polyvinyl pyrrolidone (PVP) ratio. Then, laminin-modified SNF2, namely SNF2-AP-S-L, was obtained through a series of chemical reactions to attach the extracellular matrix protein, laminin, to its surface. The SNF2-AP-S-L substrate was characterized by a combination of scanning electron microscopy (SEM), Fourier transform-infrared (FTIR) spectroscopy, nitrogen adsorption/desorption isotherms, and contact angle measurements. The results of further functional assays show that this substrate is a biocompatible, bioactive and biodegradable scaffold with good structural integrity that persisted beyond 18 days. Moreover, a synergistic effect of sustained structure support and prolonged biochemical stimulation for cell differentiation on SNF2-AP-S-L was found when neuron-like PC12 cells were seeded onto its surface. Specifically, neurite extensions on the covalently modified SNF2-AP-S-L were significantly longer than those observed on unmodified SNF and SNF subjected to physical adsorption of laminin. Together, these results indicate that the SNF2-AP-S-L substrate prepared in this study is a promising 3D biocompatible substrate capable of sustaining longer neuronal growth for tissue-engineering applications.

6.
RSC Adv ; 8(40): 22506-22514, 2018 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-35539731

RESUMO

Gas diffusion layer (GDL) is an important component related to the efficiency of proton exchange membrane fuel cells (PEMFCs). Nevertheless, the preparation cost of the conventional GDL is high. In our previous studies, a single-layer gas diffusion layer (SL-GDL) prepared by a simple and cost-effective process has been used for PEMFCs, and it achieved 85% efficiency of a commonly used commercial GDL. In this study, improvement in physical properties of a series of single-layer gas diffusion layers, SL-GDL-Gx (x = 1-3), via uniform distribution of graphene in the SL-GDL, and the application of SL-GDL-Gx in PEMFCs are studied. The results indicate that the presence of well-distributed graphene layers in SL-GDL-Gxs causes an increase in the surface roughness and the formation of irregular slender interstices, leading to the enhancement of gas permeability while maintaining the microporous layer (MPL)-like microstructure and retaining good loading and efficient utilization of the catalyst. Moreover, the electrical resistivities significantly decreased and the mechanical properties improved. These improvements in physical properties are significantly beneficial for the performance of PEMFC. The single-cell performance tests show that the best performance measured at 80 °C under 99.9% relative humidity (RH) conditions is obtained from the PEMFC (FC-2) fabricated with SL-GDL-G2 and is 46% higher than that from FC-0 with SL-GDL-G0 without graphene and 15% higher than that from FC-3 with the commercial GDL. Furthermore, the performances of FC-2 measured at 50-80 °C under 15% RH are all much higher than those of FC-3. The results indicate that SL-GDL-G2 prepared via a cost-effective method is a potential GDL for PEMFCs.

7.
ACS Biomater Sci Eng ; 3(8): 1527-1534, 2017 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-33429639

RESUMO

In this paper, a biomolding technique was first used to fabricate a scaffold of hierarchical topography with biomimetic morphology for tissue engineering. First, poly(ortho-methoxyaniline) (POMA) was synthesized by conventional oxidative polymerization, followed by characterizations with Fourier transform infrared spectroscopy (FTIR) and gel permeation chromatography (GPC). Moreover, the POMA scaffold with 3D biomimetic morphology was fabricated using poly(dimethylsiloxane) (PDMS) as negative soft template from natural leaf surfaces of Xanthosoma sagittifolium, followed by transferring the pattern of PDMS template to POMA. The as-fabricated POMA scaffold with biomimetic morphology was investigated by scanning electron microscopy (SEM). Subsequently, cell-scaffold interactions were carried out by culturing rat neural stem cells (rNSCs) on biomimetic and nonbiomimetic, or flat, POMA scaffolds, as well as on poly(d-lysine) (PDL)-coated substrate, and evaluating the corresponding adhesion, cell viability, and differentiation of rNSCs. Results showed that there was no significant difference in the attachment of rNSCs on the three surface types, however, both the biomimetic and flat POMA scaffolds induced growth arrest relative to the PDL-coated substrate. In addition, the percentage of cells with elongated neurites after 19 days of culture was higher on the biomimetic POMA scaffold relative to flat POMA and PDL. In summary, the POMA scaffold with biomimetic morphology shows promise in promoting rNSCs differentiation and neurite outgrowth for long-term studies on nerve regenerative medicine.

8.
J Biomed Mater Res A ; 104(11): 2730-43, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27345435

RESUMO

A detailed genomic and epigenomic analyses of neural stem cells (NSCs) differentiation in synthetic microenvironments is essential for the advancement of regenerative medicine and therapeutic treatment of diseases. This study identified the changes in mRNA and miRNA expression profile during NSC differentiation on an artificial matrix. NSCs were grown on a surface-modified, electrospun tetraethyl-orthosilicate nanofiber (designated as SNF-AP) by providing a 3D-environment for cell growth and differentiation. Differentially expressed mRNAs and miRNAs of NSC differentiated in this microenvironment were identified through microarray analysis. The genes and miRNA targets responsible for the differentiation fate of NSCs and neuron development process were determined using Ingenuity Pathway Analysis (IPA). SNF-AP enhanced the expression of genes that activates the proliferation, development, and outgrowth of neurons, differentiation and generation of cells, neuritogenesis, outgrowth of neurites, microtubule dynamics, formation of cellular protrusions, and long-term potentiation during NSC differentiation. On the other hand, PDL inhibited neuritogenesis, microtubule dynamics, and proliferation and differentiation of cells and activated the apoptosis function. Moreover, the nanomaterial promoted the expression of more let-7 miRNAs, which have vital roles in NSC differentiation. Overall, SNF-AP is biocompatible and applicable scaffold for NSC differentiation in the development of neural tissue engineering. These findings are useful in enhancing in vitro NSC differentiation potential for preclinical studies and future clinical applications. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 2730-2743, 2016.


Assuntos
MicroRNAs/genética , Nanofibras/química , Células-Tronco Neurais/efeitos dos fármacos , Neurogênese/efeitos dos fármacos , RNA Mensageiro/genética , Dióxido de Silício/química , Dióxido de Silício/farmacologia , Transcriptoma/efeitos dos fármacos , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Feminino , Nanofibras/ultraestrutura , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Ratos Sprague-Dawley
9.
Int J Nanomedicine ; 11: 729-41, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27013873

RESUMO

In this work, silica nanofibers (SNFs) were prepared by an electrospinning method and modified with poly-d-lysine (PDL) or (3-aminopropyl) trimethoxysilane (APTS) making biocompatible and degradable substrates for neuronal growth. The as-prepared SNF, modified SNF-PDL, and SNF-APTS were evaluated using scanning electron microscopy, nitrogen adsorption/desorption isotherms, contact angle measurements, and inductively coupled plasma atomic emission spectroscopy. Herein, the scanning electron microscopic images revealed that dissolution occurred in a corrosion-like manner by enlarging porous structures, which led to loss of structural integrity. In addition, covalently modified SNF-APTS with more hydrophobic surfaces and smaller surface areas resulted in significantly slower dissolution compared to SNF and physically modified SNF-PDL, revealing that different surface modifications can be used to tune the dissolution rate. Growth of primary hippocampal neuron on all substrates led to a slower dissolution rate. The three-dimensional SNF with larger surface area and higher surface density of the amino group promoted better cell attachment and resulted in an increased neurite density. This is the first known work addressing the degradability of SNF substrate in physiological conditions with neuron growth in vitro, suggesting a strong potential for the applications of the material in controlled drug release.


Assuntos
Materiais Biocompatíveis/química , Eletroquímica , Hipocampo/fisiologia , Nanofibras/química , Neurônios/fisiologia , Dióxido de Silício/química , Engenharia Tecidual/métodos , Animais , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Embrião de Mamíferos/citologia , Embrião de Mamíferos/fisiologia , Hipocampo/citologia , Microscopia Eletrônica de Varredura , Neurônios/citologia , Porosidade , Ratos , Silanos/química , Propriedades de Superfície
10.
J Mater Chem B ; 2(9): 1205-1215, 2014 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-32261357

RESUMO

In this study, pure silica nanofibers (SNFs) were fabricated by the electrospinning technique. Subsequently, the as-prepared SNFs were modified with (3-aminopropyl) trimethoxysilane (APTS) for applications in neural tissue engineering. The structure and properties of the as-prepared SNFs and the modified SNFs (SNF-APxM, x = 1-3) were evaluated with FTIR, TGA, nitrogen adsorption/desorption isotherms, and SEM. It was found that the surface hydrophilicity of SNF-APxM was lowered upon increasing the amino alkyl group content. The SEM and confocal images revealed that neural stem cells (NSCs) cultured on the electrospun SNFs and SNF-APxM substrates were elongated along the fibers in comparison to poly-d-lysine-coated (PDL-coated) substrate. In addition, a higher degree of proliferation and more responsive cells were observed for the NSCs cultured on the SNF-AP3M substrate than those on the SNFs and the PDL-coated substrates. The results indicated that the APTS-modified silica nanofibers can be potential substrates for regulating growth and differentiation of NSCs in culture.

11.
J Mater Chem B ; 1(40): 5469-5477, 2013 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-32261255

RESUMO

In this manuscript, neat electrospun poly(o-methoxyaniline) (POMA) fibers were applied for the first time in the growth of neural stem cells. POMA was synthesized by chemical oxidative polymerization, followed by dissolving in tetrahydrofuran/dimethylformamide to prepare electrospinning solution. Subsequently, the solution was electrospun to produce polymeric fibers. The structure, transparency and morphology of as-prepared POMA fibers were characterized by Fourier transform infrared spectroscopy, UV-visible spectroscopy and scanning electron microscopy, respectively. It was found to have no adverse effects on the long-term proliferation of the neural stem cells (NSCs), retain the ability to self-renew, and exhibit multipotentiality. Studies on cell-fiber interactions were carried out by culturing NSCs on the POMA substrate and assessing their growth, cell viability, and differentiation. Results of cell viability assay, immunofluorescence staining, quantitative real-time reverse transcription-PCR and calcium image studies confirmed that POMA electrospun fibers not only showed better NSCs attachment, but also enhanced and accelerated differentiation.

12.
Acta Biomater ; 6(4): 1462-70, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19818421

RESUMO

Mesoporous aerogel was produced under regular atmospheric conditions using the sol-gel polymerization of tetraethyl orthosilicate with an ionic liquid as both solvent and active agent. This was then used to build a three-dimensional structure to recognize nucleotide acids. Fourier transformation infrared spectroscopy, scanning electron microscopy, (29)Si solid-state nuclear magnetic resonance, and Brunauer-Emmett-Teller instruments were used to characterize this 3D aerogel, demonstrating that it had high porosity and large internal networking surface area that could capture nucleotide acids. The functionality of molecular recognition on nucleotide acids was demonstrated by immobilizing an oligonucleotide to probe its DNA target and confirming the tagged fluorescent signals by confocal laser scanning microscopy. The results indicated that the as-prepared 3D bioaerogel was capable of providing a very large surface area to capture and recognize human gene ATP5O.


Assuntos
Sondas de DNA/química , Géis/química , Nucleotídeos/análise , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Compostos de Organossilício/química , Polímeros/química , Humanos , Espectroscopia de Ressonância Magnética , Microscopia Eletrônica de Varredura , Nitrogênio/química , Conformação de Ácido Nucleico , Nucleotídeos/genética , Nucleotídeos/metabolismo , Dióxido de Silício/química , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura
13.
Acta Biomater ; 4(3): 725-32, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18065300

RESUMO

A recombinant red fluorescent protein, DsRed, was chosen as a model protein to prepare a protein-encapsulated bioaerogel, DsRed-SAG. It was prepared using sol-gel polymerization of tetraethyl orthosilicate (TEOS) with an ionic liquid as the solvent and pore-forming agent. The DsRed-SAG bioaerogel was characterized by Fourier transformation infrared, scanning electron microscopy and Brunauer-Emmett-Teller measurements. It was found that the as-prepared bioaerogel had high porosity, and the silica network exhibited little shrinkage during the drying process. The stability of the bioaerogel was monitored by fluorescence spectroscopy and confirmed by confocal laser scanning microscopy. In addition, the protection of the encapsulated proteins by the silica network was further investigated using the degradation test by a protease. The results indicated that the as-prepared protein was quite stable during formation of the protein-containing wet gel and extraction of the ionic liquid, demonstrating that the new method can be extended to prepare other protein-encapsulated bioaerogels.


Assuntos
Géis/metabolismo , Proteínas Luminescentes/metabolismo , Teste de Materiais/métodos , Modelos Biológicos , Adsorção , Animais , Insetos , Microscopia Confocal , Microscopia Eletrônica de Varredura , Nitrogênio , Dióxido de Silício/metabolismo , Espectrometria de Fluorescência , Espectroscopia de Infravermelho com Transformada de Fourier , Proteína Vermelha Fluorescente
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