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1.
RSC Adv ; 14(3): 2027-2035, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38196913

RESUMO

Herbal hydrogels as a new class of sustainable functional materials have attracted extensive attention. However, the development of herbal hydrogels is significantly hindered due to their poor hydrogel performances and the lack of universal preparation methods. In this study, four herbal hydrogels composed of phytochemical polyphenols and stevioside compounds are prepared through a facile heating-cooling process, where multiple hydrogen bonding interactions between two monomers provide the main driving force for gelation. These herbal hydrogels exhibit thermo-sensitivity and good reversibility (25-90 °C), robust adhesion behaviours on hydrophilic and hydrophobic surfaces (maximum adhesion strength of 591.7 kPa), and outstanding antibacterial properties (100% bacteriostatic ratio). Profiting from these intriguing characteristics, they are demonstrated to show great potential as natural antibacterial coatings by depositing thin hydrogel layers onto diverse substrates. More importantly, the hydrogel coatings could be easily recycled by thermal regelation and reused at least 5 times. This work proposes a simple and universal strategy for preparing functional hydrogels based on binary herbal small molecules, which also sheds light on the development of reusable hydrogel coatings.

2.
R Soc Open Sci ; 8(3): 202148, 2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33959366

RESUMO

Ethylenediamine tetraacetic acid (EDTA) is considered an effective crystal growth modifier for template-assisted hydrothermal synthesis of hydroxyapatite (HA) materials. In this work, flowerlike-carbonated HA (CHA) microspheres were synthesized using EDTA via a one-step hydrothermal route. The phase, functional groups, morphology and particle size distribution of the products were examined by X-ray diffraction, Fourier transform infrared spectrometer, field emission scanning electron microscopy as well as laser diffraction particle size analysis. Results show that the morphology of the products can be well controlled by adjusting the EDTA concentration. With an increase of the EDTA concentration, the particle size of flowerlike microspheres decreased from tens of microns down to a few microns. The underlying mechanism for the morphological transition of CHA microspheres with different concentrations of EDTA under hydrothermal conditions is proposed. This work provides a simple way to controllably fabricate CHA microspheres with various sizes using the same synthesis system for biomedical applications, such as cell carriers and drug delivery.

3.
RSC Adv ; 11(5): 2693-2700, 2021 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-35424214

RESUMO

Catalysts used for the oxygen reduction reaction (ORR) are crucial to fuel cells. However, the development of novel catalysts possessing high activity at a low cost is very challenging. Recently, extensive research has indicated that nitrogen-doped carbon materials, which include nonprecious metals as well as metal-based oxides, can be used as excellent candidates for the ORR. Here, Co/Co3O4@N-doped carbon (NC) with a low cost and highly stable performance is utilized as an ORR electrocatalyst through the pyrolysis of an easily prepared physical mixture containing a cobalt-based zeolite imidazolate framework (ZIF-67 precursor) and biomass materials from poplar flowers. Compared with the pure ZIF-derived counterpart (Co@NC) and PL-bio-C, the as-synthesized electrocatalysts show significantly enhanced ORR activities. The essential roles of doped atoms (ZIF-67 precursor) in improving the ORR activities are discussed. Depending mainly on the formation of Co-Co3O4 active sites and abundant nitrogen-containing groups, the resulting Co/Co3O4@NC catalyst exhibits good electroactivity (onset and half-wave potentials: E onset = 0.94 V and E 1/2 = 0.85 V, respectively, and a small Tafel slope of 90 mV dec-1) compared to Co@NC and PL-bio-C and follows the 4-electron pathway with good stability and methanol resistance. The results of this study provide a reference for exploring cobalt-based N-doped biomass carbon for energy conversion and storage applications.

4.
RSC Adv ; 11(57): 35718-35725, 2021 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-35492789

RESUMO

The electronic and transport properties of fluorographane (C2HF) nanoribbons, i.e., bare (B-C2HF) and hydrogen-passivated (H-C2HF) C2HF nanoribbons, are extensively investigated using first-principles calculations. The results indicate that edge states are present in all the B-C2HF nanoribbons, which are not allowed in the H-C2HF nanoribbons regardless of the directions. The spin splitting phenomenon of band structure only appears in the zigzag direction. This behavior mainly originates from the dehydrogenation operation, which leads to sp2 hybridization at the edge. The H-C2HF nanoribbons are semiconductors with wide band gaps. However, the band gap of B-C2HF nanoribbons is significantly reduced. Remarkably, the phase transition can be induced by the changes in the magnetic coupling at the nanoribbon edges. In addition, the B-C2HF nanoribbons along the zigzag direction show optimal conductivity, which is consistent with the band structures. Furthermore, a perfect spin filtering controller can be achieved by changing the magnetization direction of the edge C atoms. These results may serve as a useful reference for the application of C2HF nanoribbons in spintronic devices.

5.
Materials (Basel) ; 13(12)2020 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-32604917

RESUMO

CuCo2O4 decoration carbon nanofibers (CNFs) as an enzyme-free glucose sensor were fabricated via electrospinning technology and carbonization treatment. The CNFs with advantages of abundant nitrogen amounts, porosity, large surface area, and superior electrical conductivity were used as an ideal matrix for CuCo2O4 decoration. The resultant CuCo2O4-CNF hybrids possessed favorable properties of unique three-dimensional architecture and good crystallinity, accompanied by the CuCo2O4 nanoparticles uniformly growing on the CNF skeleton. To further enhance the selective molecular recognition capacity of the developed sensor, a conductive film was synthesized through the electropolymerization of thiophene and thiophene-3-boronic acid (TBA). Based on the synergistic effects of the performances of CNFs, CuCo2O4 nanoparticles, and boronic acid-decorated polythiophene layer, the obtained poly(thiophene-3-boronic acid) (PTBA)/CuCo2O4-CNF-modified electrodes (PTBA/CuCo2O4-CNFs/glassy carbon electrode (GCE)) displayed prominent electrocatalytic activity toward electro-oxidation of glucose. The fabricated sensor presented an outstanding performance in the two linear ranges of 0.01-0.5 mM and 0.5-1.5 mM, with high selectivity of 2932 and 708 µA·mM-1·cm-2, respectively. The composite nanofibers also possessed good stability, repeatability, and excellent anti-interference selectivity toward the common interferences. All these results demonstrate that the proposed composite nanofibers hold great potential in the application of constructing an enzyme-free glucose sensing platform.

6.
Anticancer Agents Med Chem ; 19(14): 1754-1761, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31364518

RESUMO

BACKGROUND: Rapamycin receptor inhibitors have been applied in the clinic and achieved satisfactory therapeutic effect recently. The mechanisms did not clearly show how the Celastrus Orbiculatus Extracts (COE) inhibited the expression of the mammalian Target of Rapamycin (mTOR) in human gastric cancer cells. The aim of this study was to investigate whether the COE inhibited the metastasis through the mTOR signaling pathway in human gastric cancer MGC-803 cells. METHODS: The abnormal expression level of mTOR protein was detected by immunohistochemistry in human gastric cancer tissue. The MGC-803/mTOR- cells were constructed by knockdown of mTOR using lentivirus infection technique. The human gastric cancer MGC-803/mTOR- cells were treated with different concentrations (20, 40, 80 µg/ml) of COE for 24 hours. The ability of cell metastasis was analyzed by the cell invasion and migration assay. The expression levels of PI3K/Akt/mTOR signaling pathway were detected by Western Blotting. RESULTS: COE inhibited the proliferation, invasion and migration of MGC-803/mTOR- cells in a concentrationdependent manner. The expression of E-cadherin protein increased, and the expression of N-cadherin and Vimentin decreased simultaneously in the MGC-803/mTOR- cells. 4EBP1, p-4EBP1, P70S6k, p-P70S6k, mTOR, p-mTOR, PI3K and Akt proteins in MGC-803/mTOR- cells were reduced in a dose-dependent manner. CONCLUSION: COE could not only inhibit cell growth, invasion and migration, but also inhibit the epithelialmesenchymal transition of gastric cancer cells. The molecular mechanism of COE inhibited the metastasis which may be related to the PI3K/Akt/mTOR signal pathway. This study provides ideas for the development of new anti-gastric cancer drugs.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Celastrus/química , Fosfatidilinositol 3-Quinases/metabolismo , Extratos Vegetais/farmacologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Neoplasias Gástricas/tratamento farmacológico , Serina-Treonina Quinases TOR/antagonistas & inibidores , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Relação Estrutura-Atividade , Serina-Treonina Quinases TOR/metabolismo
7.
J Clin Ultrasound ; 45(5): 304-309, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28186627

RESUMO

BACKGROUND: To assess the efficacy of three-section contrast-enhanced transrectal ultrasonography (CETRUS) in prostate cancer (PCa) detection. METHODS: A total of 169 consecutive patients with either PSA level ≥ 4 ng/ml or abnormal digital rectal examination findings were prospectively enrolled in this single center study. All patients underwent baseline transrectal ultrasonography (TRUS) and three-section CETRUS by one investigator blinded to any clinical data before TRUS-guided transperineal biopsy. The performances of baseline TRUS, single-section, and three-section CETRUS for PCa detection were compared. RESULTS: On a per-patient basis, the sensitivity, specificity, and overall accuracy for detecting PCa with three-section CETRUS was 92.3%, 69.2%, and 78.1%, respectively. In comparison with conventional (single-section) CETRUS (sensitivity 75.4%, specificity 72.1%, and accuracy 73.4%), three-section CETRUS performed significantly better (p < 0.05, McNemar test). Additionally, the low-grade PCa detection rate for three-section CETRUS was significantly higher than that of conventional CETRUS (26.7% versus 10.2%, p < 0.05). CONCLUSIONS: Our study demonstrated a significant benefit of three-section CETRUS relative to conventional CETRUS, and this technique may find more PCa patients eligible for active surveillance. © 2016 Wiley Periodicals, Inc. J Clin Ultrasound 45:304-309, 2017.


Assuntos
Meios de Contraste , Aumento da Imagem/métodos , Neoplasias da Próstata/diagnóstico por imagem , Ultrassonografia/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Próstata/diagnóstico por imagem , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
8.
Int J Cancer ; 140(6): 1457-1464, 2017 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-27914101

RESUMO

Ultraconserved regions (UCRs) are non-protein coding gene sequences that are strictly conserved across among different species. Emerging evidence demonstrates that transcribed ultraconserved regions (TUCRs) encoding noncoding RNAs serve as regulators of gene expression. In recent decades, increasing evidence implicates the involvement of UCRs in carcinogenesis. The role of TUC.338 in cervical cancers was an oncogene in previous studies. Until now, the role of TUC.338 in colorectal cancers remains undefined. This study revealed that TUC.338 is significantly up-regulated in colorectal cancers (CRC) tissue and CRC cell lines, and the up-regulated TUC.338 is associated with lymph node metastasis. Transfection with small interfering RNA (siRNA) markedly inhibited cell migration and invasion in SW480 and HCT116 colorectal cancer cell lines. TIMP-1 was demonstrated to be negatively regulated by TUC.338 at the posttranscriptional level, via a specific target site within the 3' untranslated region by dual-luciferase reporter assay. The expression of TIMP-1 was also observed to inversely correlate with TUC.338 expression in CRC tissues. Over-expression of TIMP-1 with migRI-TIMP-1-GFP inhibited CRC cell migration and invasion and down-regulates MMP9, resembling that of TUC.338-siRNA. Thus, these findings suggested that TUC.338 acts as a novel oncogene by targeting the TIMP-1 gene thus promoting colorectal cancer cell migration and invasion.


Assuntos
Adenocarcinoma/patologia , Neoplasias Colorretais/patologia , RNA Longo não Codificante/fisiologia , RNA Neoplásico/fisiologia , Regiões 3' não Traduzidas/genética , Adenocarcinoma/genética , Adulto , Idoso , Linhagem Celular Tumoral , Movimento Celular , Neoplasias Colorretais/genética , Sequência Conservada/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Metaloproteinase 9 da Matriz/biossíntese , Metaloproteinase 9 da Matriz/genética , Pessoa de Meia-Idade , Invasividade Neoplásica/genética , Metástase Neoplásica/genética , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Oncogenes , Interferência de RNA , RNA Longo não Codificante/genética , RNA Neoplásico/biossíntese , RNA Neoplásico/genética , RNA Interferente Pequeno/genética , Inibidor Tecidual de Metaloproteinase-1/biossíntese , Inibidor Tecidual de Metaloproteinase-1/genética
9.
Int J Clin Exp Pathol ; 10(11): 10759-10769, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-31966419

RESUMO

Lung adenocarcinoma (LAC) is one of the common reasons of cancer-related death with few biomarkers for diagnosis and prognosis. Solute carrier family 2 member 1 protein, SLC2A1, has been associated with tumor progression, metastasis, and poor prognosis in many human solid tumors. However, little is reported about its biological functions in lung adenocarcinoma. Here we observed a strong up-regulation of SLC2A1 in patients with LAC and found that SLC2A1 was significantly correlated with prognosis. Knockdown of SLC2A1 in LAC cells inhibits cellular proliferation and plate clone formation in vitro as well as suppression of glucose utilization. Meanwhile, silencing of SLC2A1 also suppresses tumor metastasis in vitro. Mechanistically, GSEA showed that genes in cell cycle pathway were prominently enriched in the higher SLC2A1 group. By a large-scale proteomic analysis, we revealed that cell cycle protein level was significantly increased in SLC2A1-high group. Collectively, our findings indicate that elevated SLC2A1 is a critical modulator in lung adenocarcinoma progression by altering glucose metabolism and the cell cycle pathway, and also suggest SLC2A1 as a promising target for lung adenocarcinoma therapy.

10.
Mater Sci Eng C Mater Biol Appl ; 48: 487-98, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25579950

RESUMO

In this study, a novel hydrogel, chitosan (CS) crosslinked carboxymethyl-ß-cyclodextrin (CM-ß-CD) polymer modified Fe3O4 magnetic nanoparticles was synthesized for delivering hydrophobic anticancer drug 5-fluorouracil (CS-CDpoly-MNPs). Carboxymethyl-ß-cyclodextrin being grafted on the Fe3O4 nanoparticles (CDpoly-MNPs) contributed to an enhancement of adsorption capacities because of the inclusion abilities of its hydrophobic cavity with insoluble anticancer drugs through host-guest interactions. Experimental results indicated that the amounts of crosslinking agent and bonding times played a crucial role in determining morphology features of the hybrid nanocarriers. The nanocarriers exhibited a high loading efficiency (44.7±1.8%) with a high saturation magnetization of 43.8emu/g. UV-Vis spectroscopy results showed that anticancer drug 5-fluorouracil (5-Fu) could be successfully included into the cavities of the covalently linked CDpoly-MNPs. Moreover, the free carboxymethyl groups could enhance the bonding interactions between the covalently linked CDpoly-MNPs and anticancer drugs. In vitro release studies revealed that the release behaviors of CS-CDpoly-MNPs carriers were pH dependent and demonstrated a swelling and diffusion controlled release. A lower pH value led to swelling effect and electrostatic repulsion contributing to the protonation amine impact of NH3(+), and thus resulted in a higher release rate of 5-Fu. The mechanism of 5-Fu encapsulated into the magnetic chitosan nanoparticles was tentatively proposed.


Assuntos
Antimetabólitos Antineoplásicos/química , Quitosana/química , Materiais Revestidos Biocompatíveis/química , Sistemas de Liberação de Medicamentos , Fluoruracila/química , Nanopartículas de Magnetita/química , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas
11.
Int J Cardiol ; 168(3): 2498-505, 2013 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-23541609

RESUMO

BACKGROUND: Emerging evidence underlines the role of inflammation activation in the process of cardiac fibrosis. Triptolide has potent anti-inflammatory and anti-proliferative properties, and extensively used in the treatment of chronic inflammatory disorders. In the current study, we test the hypothesis that triptolide treatment facilitates to attenuate chronic pressure overload-induced cardiac fibrosis in a model of rat. METHODS: Adult male Sprague-Dawley rats were subjected to a suprarenal abdominal aorta constriction (AC) or sham (as control) to induce sustained pressure overload. Eight weeks later, rats were randomly assigned to receive triptolide (9 µg/kg.d, i.p) or vehicle (0.1% dimethyl sulfoxide, 0.2 ml/d, i.p) treatment for an additional 8 weeks. RESULTS: AC caused significant pathological hypertrophy, cardiac fibrosis and reduced cardiac diastolic function. Triptolide treatment markedly inhibited AC-induced increases in myocardial collagen volume fraction, collagen type I/III deposition, left ventricular end-diastolic pressure, expressions of pro-fibrogenic factors (transforming growth factor-ß and angiotensin II) and pro-inflammatory cytokines (IL-1ß and IL-6), NF-κB activation and inflammatory cell infiltration in left ventricles compared with vehicle, without affecting cardiac hypertrophy. However, triptolide had no effects on systemic blood pressure and circulating angiotensin II level. CONCLUSIONS: Collectively, the findings suggested that triptolide treatment elicits favorable anti-fibrogenic effect in a blood pressure-independent manner, at least in part, through inhibiting myocardial pro-fibrogenic factor production and inflammatory activation in the pressure overloaded heart.


Assuntos
Diterpenos/uso terapêutico , Imunossupressores/uso terapêutico , Miocárdio/patologia , Fenantrenos/uso terapêutico , Animais , Compostos de Epóxi/uso terapêutico , Fibrose/etiologia , Fibrose/prevenção & controle , Masculino , Pressão , Ratos , Ratos Sprague-Dawley
12.
Zhonghua Bing Li Xue Za Zhi ; 42(11): 744-7, 2013 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-24447551

RESUMO

OBJECTIVE: To study the clinicopathologic features, immunophenotype, molecular genetics and differential diagnosis of solid variant of angiomatoid fibrous histocytoma. METHODS: The clinicopathologic features of 3 cases of solid variant of angiomatoid fibrous histocytoma were analyzed and the literature was reviewed. RESULTS: There were a total of 2 males and 1 female. The age of patients ranged from 9 to 12 years. The patients presented with a painless mass located in left forearm, left knee or back. The lesions were treated by complete surgical resection. On gross examination, the tumors varied from 1.6 cm to 4.5 cm in greatest dimension. They were well-circumscribed and had pale yellow to grayish-red solid cut surface. Histologically, the tumor was composed of histocytoid cells arranged in sheet-like pattern. A fibrous pseudocapsule surrounded by lymphocytes and plasma cells was identified. Immunohistochemical study showed that the tumor cells in all cases were positive for vimentin and CD68. They were negative for S100 protein, cytokeratin, CD34, CD31, smooth muscle actin, CD35, CD21 and CD30. Two cases also expressed CD99 and one of them was positive for desmin and epithelial membrane antigen. Fluorescence in-situ hybridization was positive for EWSR1 gene. CONCLUSIONS: Solid type represents a variant of angiomatoid fibrous histocytoma and is considered as tumor of borderline malignant potential. Definitive diagnosis requires thorough histologic examination and clinical correlation. Immunohistochemistry and EWSR1 gene study are helpful in further delineation and differential diagnosis. Complete resection or wide local excision with post-operative follow up is the main modality of treatment.


Assuntos
Histiocitoma Fibroso Maligno/patologia , Neoplasias de Tecidos Moles/patologia , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Dorso , Proteínas de Ligação a Calmodulina/genética , Criança , Sarcoma de Células Dendríticas Foliculares/metabolismo , Sarcoma de Células Dendríticas Foliculares/patologia , Diagnóstico Diferencial , Feminino , Antebraço , Histiocitoma Fibroso Maligno/genética , Histiocitoma Fibroso Maligno/metabolismo , Histiocitoma Fibroso Maligno/cirurgia , Humanos , Joelho , Masculino , Neoplasias de Tecido Muscular/patologia , Neurilemoma/metabolismo , Neurilemoma/patologia , Proteína EWS de Ligação a RNA , Proteínas de Ligação a RNA/genética , Neoplasias de Tecidos Moles/genética , Neoplasias de Tecidos Moles/metabolismo , Neoplasias de Tecidos Moles/cirurgia , Vimentina/metabolismo
14.
Mediators Inflamm ; 2009: 389720, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19884981

RESUMO

Excessive immune activation and inflammatory mediators may play a critical role in the pathogenesis of chronic heart failure. Methotrexate is a commonly used anti-inflammatory and immunosuppressive drug. In this study, we used a rat model of cardiac myosin-induced experimental autoimmune myocarditis to investigate the effects of low-dose methotrexate (0.1 mg/kg/d for 30 d) on the plasma level of cytokines and cardiac remodeling and function. Our study showed that levels of tumor necrosis factor-(TNF-)alpha and interleukin-6 (IL-6) are significantly increased in postmyocarditis rats, compared with the control rats. Methotrexate treatment reduced the plasma levels of TNF-alpha and IL-6 and increased IL-10 level, compared to saline treatment. In addition, postmyocarditis rats showed significant cardiac fibrosis characterized by increased myocardial collagen volume fraction, perivascular collagen area, and the ratio of collagen type I to type III, compared with the control rats. However, MTX treatment not only markedly attenuated cardiac fibrosis, diminished the left ventricular end-diastolic dimension, but also increased the left ventricular ejection fraction and fractional shortening. Collectively, these results suggest that low-dose methotrexate has ability to regulate inflammatory responses and improves cardiac function and hence contributes to prevent the development of postmyocarditis dilated cardiomyopathy.


Assuntos
Citocinas/sangue , Coração/efeitos dos fármacos , Metotrexato/farmacologia , Miocardite/tratamento farmacológico , Animais , Colágeno Tipo I/sangue , Colágeno Tipo III/sangue , Modelos Animais de Doenças , Imunossupressores/farmacologia , Interleucina-10/sangue , Interleucina-6/sangue , Masculino , Ratos , Ratos Endogâmicos Lew , Suínos , Fator de Necrose Tumoral alfa/sangue , Remodelação Ventricular
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