Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 14 de 14
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
J Colloid Interface Sci ; 673: 874-882, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38908286

RESUMO

The quest for efficient hydrogen production highlights the need for cost-effective and high-performance catalysts to enhance the electrochemical water-splitting process. A significant challenge in developing self-supporting catalysts lies in the high cost and complex modification of traditional substrates. In this study, we developed catalysts featuring superaerophobic microstructures engineered on microspherical nickel-coated Chinese rice paper (Ni-RP), chosen for its affordability and exceptional ductility. These catalysts, due to their microspherical morphology and textured surface, exhibited significant superaerophobic properties, substantially reducing bubble adhesion. The nickel oxy-hydroxide (NiOxHy) and phosphorus-doped nickel (PNi) catalysts on Ni-RP demonstrated effective roles in oxygen evolution reaction (OER) and hydrogen evolution reaction (HER), achieving overpotentials of 250 mV at 20 mA cm-2 and 87 mV at -10 mA cm-2 in 1 M KOH, respectively. Moreover, a custom water-splitting cell using PNi/Ni-RP and NiOxHy/Ni-RP electrodes reached an impressive average voltage of 1.55 V at 10 mA cm-2, with stable performance over 100 h in 1 M KOH. Our findings present a cost-effective, sustainable, and easily modifiable substrate that utilizes superaerophobic structures to create efficient and durable catalysts for water splitting. This work serves as a compelling example of designing high-performance self-supporting catalysts for electrocatalytic applications.

2.
Front Immunol ; 13: 1022720, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36389726

RESUMO

Numerous studies have demonstrated the important roles of epigenetic modifications in tumorigenesis, progression and prognosis. However, in hepatocellular carcinoma, the potential link between N7-methylguanosine (m7G) modification and molecular heterogeneity and tumor microenvironment (TME) remains unclear. Method: We performed a comprehensive evaluation of m7G modification patterns in 816 hepatocellular carcinoma samples based on 24 m7G regulatory factors, identified different m7G modification patterns, and made a systematic correlation of these modification patterns with the infiltration characteristics of immunocytes. Then, we built and validated a scoring tool called m7G score. Results: In this study, we revealed the presence of three distinct m7G modification patterns in liver cancer, with remarkable differences in the immunocyte infiltration characteristics of these three subtypes. The m7G scoring system of this study could assess m7G modification patterns in individual hepatocellular carcinoma patients, could predict TME infiltration characteristics, genetic variants and patient prognosis. We also found that the m7G scoring system may be useful in guiding patients' clinical use of medications. Conclusions: This study revealed that m7G methylation modifications exerted a significant role in formation of TME in hepatocellular carcinoma. Assessing the m7G modification patterns of single patients would help enhance our perception of TME infiltration characteristics and give significant insights into immunotherapy efficacy.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Metilação , Epigênese Genética , Processamento de Proteína Pós-Traducional , Microambiente Tumoral
3.
Nano Lett ; 21(19): 8126-8134, 2021 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-34570519

RESUMO

Photothermal bimorph actuators have attracted considerable attention in intelligent devices because of their cordless control and lightweight and easy preparation. However, current photothermal bimorph actuators are mostly based on films or papers driven by near-infrared sources, which are deficient in flexibility and adaptability, restricting their potential in wearable applications. Herein, a bimorph textile actuator that can be scalably fabricated with a traditional textile route and autonomously triggered by sunlight is reported. The active layer and passive layer of the bimorph are constructed by polypropylene tape and a MXene-modified polyamide filament. Because of the opposite thermal expansion and MXene-enhanced photothermal efficiency (>260%) of the bimorph, the textile actuator presents effective deformation (1.38 cm-1) under low sunlight power (100 mW/cm2). This work provides a new pathway for wearable sunlight-triggered actuators and finds attractive applications for smart textiles.


Assuntos
Dispositivos Eletrônicos Vestíveis , Nylons , Polipropilenos , Luz Solar , Têxteis
4.
Genome Biol ; 22(1): 22, 2021 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-33413586

RESUMO

There are no comprehensive methods to identify N6-methyladenosine (m6A) at single-base resolution for every single transcript, which is necessary for the estimation of m6A abundance. We develop a new pipeline called Nanom6A for the identification and quantification of m6A modification at single-base resolution using Nanopore direct RNA sequencing based on an XGBoost model. We validate our method using methylated RNA immunoprecipitation sequencing (MeRIP-Seq) and m6A-sensitive RNA-endoribonuclease-facilitated sequencing (m6A-REF-seq), confirming high accuracy. Using this method, we provide a transcriptome-wide quantification of m6A modification in stem-differentiating xylem and reveal that different alternative polyadenylation (APA) usage shows a different ratio of m6A.


Assuntos
Adenosina/análogos & derivados , Adenosina/metabolismo , Sequenciamento por Nanoporos , Nanoporos , Populus/metabolismo , Análise de Sequência de RNA , Xilema/metabolismo , Adenosina/genética , Algoritmos , Sequência de Bases , Diferenciação Celular , Perfilação da Expressão Gênica , Imunoprecipitação , Poliadenilação , Populus/genética , Transcriptoma , Xilema/genética
5.
Sci Rep ; 11(1): 823, 2021 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-33436913

RESUMO

The challenge of decoding information about complex diseases hidden in huge number of single nucleotide polymorphism (SNP) genotypes is undertaken based on five dbGaP studies. Current genome-wide association studies have successfully identified many high-risk SNPs associated with diseases, but precise diagnostic models for complex diseases by these or more other SNP genotypes are still unavailable in the literature. We report that lung cancer, breast cancer and prostate cancer as the first three top cancers worldwide can be predicted precisely via 240-370 SNPs with accuracy up to 99% according to leave-one-out and 10-fold cross-validation. Our findings (1) confirm an early guess of Dr. Mitchell H. Gail that about 300 SNPs are needed to improve risk forecasts for breast cancer, (2) reveal an incredible fact that SNP genotypes may contain almost all information that one wants to know, and (3) show a hopeful possibility that complex diseases can be precisely diagnosed by means of SNP genotypes without using phenotypical features. In short words, information hidden in SNP genotypes can be extracted in efficient ways to make precise diagnoses for complex diseases.


Assuntos
Neoplasias da Mama/diagnóstico , Neoplasias Pulmonares/diagnóstico , Neoplasias da Próstata/diagnóstico , Algoritmos , Neoplasias da Mama/genética , Biologia Computacional , Simulação por Computador , Bases de Dados Genéticas , Feminino , Estudo de Associação Genômica Ampla/métodos , Genótipo , Humanos , Neoplasias Pulmonares/genética , Masculino , Fenótipo , Polimorfismo de Nucleotídeo Único , Neoplasias da Próstata/genética
6.
Soft Matter ; 16(6): 1636-1641, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-31960008

RESUMO

In this paper, we developed a novel morphing surface technique consisting of a 3D printed miniature groove structure and injected stimuli-responsive hydrogel pattern, which is capable of switching between lipophilicity and oleophobicity under certain stimuli. Under swelling, the geometrical change of the hydrogel will buckle the surface due to the structural confinement and create a continuous transition of surface topology. Thus, it will yield a change in the surface wetting property from oleophilic to super-oleophobic with a contact angle of oil of 85° to 165°. We quantitatively investigate this structure-property relationship using finite element analysis and analytical modeling, and the simulation results and the modeling are in good agreement with the experimental ones. This morphing surface also holds potential to be developed into an autonomous system for future sub-sea/off-shore engineering applications to separate oil and water.

7.
ACS Appl Mater Interfaces ; 11(39): 36259-36269, 2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31500411

RESUMO

Well-designed 2D materials with ultrathin structures show great potential for humidity-sensing performance owing to their high surface-volume ratio and a great number of exposed atoms on the surface. However, some sensing elements employed for healthcare applications may be considered as potentially risky, such as inflammation, granuloma formation, and carcinogenesis. Herein, we explored biofriendly humidity-sensing characteristics inspired by the great biocompatibility and conductivity of hyperbranched polyethyleneimine-capped gold nanoparticles and cross-linked with polydopamine from the adhesive proteins in mussels. It was successfully employed into two kinds of wearable devices, sports watches and breathing masks, for real-time recording humidity's fluctuation in expiration and sweat with changes of individual's crying, laughing, nervous, sleeping, training, and cold states. The wearable devices allow us to monitor individual's physical activities and emotional states well, suggesting a promising prospect in safe, reusable, long term, and noncontact human health monitoring applications.


Assuntos
Emoções , Ouro , Nanopartículas Metálicas , Dispositivos de Proteção Respiratória , Dispositivos Eletrônicos Vestíveis , Humanos , Monitorização Fisiológica
8.
Ultrasound Med Biol ; 45(3): 684-692, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30638967

RESUMO

The purpose of this study was to compare acoustic structure quantification (ASQ) with transient elastography for staging liver fibrosis. One hundred eighty-two patients with chronic hepatitis B and without moderate to severe hepatic steatosis scheduled for liver biopsy underwent ASQ and transient elastography examinations. All ASQ parameters, including total mode, total average, red mode, red average, red standard deviation, blue mode, blue average, blue standard deviation and focal disturbance (FD) ratio and liver stiffness obtained via transient elastography were found to correlate with fibrosis stage (Spearman's r = 0.783, 0.791, 0.750, 0.771, 0.544, 0.718, 0.691, 0.439, 0.815 and 0.814, respectively; all p values < 0.001). Among the ASQ parameters, the FD ratio had the highest correlation with the stage of fibrosis. The areas under the receiver operating characteristic curves (AUCs) of FD ratio and liver stiffness were 0.911 and 0.906 for F ≥ F1, 0.918 and 0.882 for F ≥ F2, 0.911 and 0.914 for F ≥ F3 and 0.926 and 0.978 for F = F4, respectively. There was no significant difference in AUCs between FD ratio and liver stiffness in predicting different stages of fibrosis (p = 0.062-0.912). ASQ is a promising technique for assessing liver fibrosis in the absence of moderate to severe hepatic steatosis.


Assuntos
Técnicas de Imagem por Elasticidade/métodos , Fígado Gorduroso/diagnóstico por imagem , Fígado Gorduroso/etiologia , Hepatite B Crônica/complicações , Adolescente , Adulto , Idoso , Biópsia , Fígado Gorduroso/patologia , Feminino , Hepatite B Crônica/patologia , Humanos , Fígado/diagnóstico por imagem , Fígado/patologia , Cirrose Hepática , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Índice de Gravidade de Doença , Adulto Jovem
9.
ACS Appl Mater Interfaces ; 7(7): 3871-6, 2015 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-25647481

RESUMO

Because of the intensified competition of land resources for growing food and natural textile fibers, there is an urgent need to reuse and recycle the consumed/wasted natural fibers as regenerated green materials. Although polypeptide was extracted from wool by alkaline hydrolysis, the size of the polypeptide fragments could be reduced to nanoscale. The wool polypeptide particles were fragile and could be crushed down to nano size again and dispersed evenly among polymer matrix under melt extrusion condition. The nano polypeptide particles could reinforce antiultraviolet capability, moisture regain, and mechanical properties of the polymer-polypeptide composite fibers.


Assuntos
Nanocompostos/química , Peptídeos/química , Polímeros/química , Resíduos/análise , Lã/química , Animais , Reciclagem , Resistência à Tração
10.
Neurol Sci ; 35(3): 415-9, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24052449

RESUMO

Neural progenitor cell (NPC) transplantation offers great potential to treat spinal cord injury (SCI). NPCs may replace lost neurons or oligodendrocytes and act as a source of neurotrophic factors to support survival of remaining cells. However, their efficiency was limited by poor survival after transplantation, and they tended more to differentiate into astrocytes, but not neurons and oligodendrocytes. This study investigated whether activated microglia is a factor that contributes to this phenomenon. Organotypic spinal cord slice (SCS) culture was used to mimic the local environment after SCI, and NPCs were co-cultured with them to share the culture medium. After specific depletion of microglia in the SCSs with clodronate loaded liposome, the apoptotic rate of NPCs decreased, more NPCs differentiated into neurons, and glial differentiation was impaired. This suggested that microglia may impair NPC survival, and neuronal differentiation, but improve astrocyte differentiation. In NPC transplantation strategy for SCI, microglia would be manipulated to improve the survival and neuronal differentiation of NPCs.


Assuntos
Apoptose/fisiologia , Diferenciação Celular/fisiologia , Microglia/fisiologia , Células-Tronco Neurais/fisiologia , Medula Espinal/citologia , Animais , Animais Recém-Nascidos , Apoptose/efeitos dos fármacos , Proteínas de Ligação ao Cálcio/metabolismo , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Ácido Clodrônico/farmacologia , Técnicas de Cocultura , Ectodisplasinas/metabolismo , Embrião de Mamíferos , Proteínas dos Microfilamentos/metabolismo , Microglia/efeitos dos fármacos , Proteínas do Tecido Nervoso/metabolismo , Células-Tronco Neurais/efeitos dos fármacos , Técnicas de Cultura de Órgãos , Fosfolipídeos/farmacologia , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
11.
PLoS One ; 8(9): e72435, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24023739

RESUMO

Activation of the stem cell transcriptional circuitry is an important event in cancer development. Although cancer cells demonstrate a stem cell-like gene expression signature, the epigenetic regulation of pluripotency-associated genes in cancers remains poorly understood. In this study, we characterized the epigenetic regulation of the pluripotency-associated genes NANOG, OCT4, c-MYC, KLF4, and SOX2 in a variety of cancer cell lines and in primary tumor samples, and investigated the re-activation of pluripotency regulatory circuits in cancer progression. Differential patterns of DNA methylation, histone modifications, and gene expression of pluripotent genes were demonstrated in different types of cancers, which may reflect their tissue origins. NANOG promoter hypomethylation and gene upregulation were found in metastatic human liver cancer cells and human hepatocellular carcinoma (HCC) primary tumor tissues. The upregulation of NANOG, together with p53 depletion, was significantly associated with clinical late stage of HCC. A pro-metastatic role of NANOG in colon cancer cells was also demonstrated, using a NANOG-overexpressing orthotopic tumor implantation mouse model. Demethylation of NANOG promoter was observed in CD133+(high) cancer cells. In accordance, overexpression of NANOG resulted in an increase in the population of CD133+(high) cells. In addition, we demonstrated a cross-regulation between OCT4 and NANOG in cancer cells via reprogramming of promoter methylation. Taken together, epigenetic reprogramming of NANOG can lead to the acquisition of stem cell-like properties. These results underscore the restoration of pluripotency circuits in cancer cells as a potential mechanism for cancer progression.


Assuntos
Carcinoma Hepatocelular/epidemiologia , Epigênese Genética/genética , Neoplasias Hepáticas/epidemiologia , Animais , Metilação de DNA/genética , Citometria de Fluxo , Células HCT116 , Proteínas de Homeodomínio/genética , Humanos , Fator 4 Semelhante a Kruppel , Camundongos , Camundongos Nus , Proteína Homeobox Nanog , Regiões Promotoras Genéticas/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteína Supressora de Tumor p53/genética
12.
Neurosci Lett ; 542: 30-6, 2013 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-23518153

RESUMO

Neural progenitor cell (NPC) transplantation offers great potential to treat spinal cord injury (SCI), but their efficiency is limited by poor survival and neuronal differentiation after transplantation. In the injury site, microglia may become activated and participate in the inflammation reaction. In vitro studies indicated that activated microglia might impair NPC survival and neuronal differentiation, but resting microglia did not. This study investigated the potential of minocycline to modify the negative effects of activated microglia on NPCs in vitro. First, the direct effects of minocycline on NPCs were tested. The results showed that at the concentration of 10µg/ml or lower, minocycline did not affect NPC survival and proliferation, but impaired neuronal differentiation. Then microglia were activated with lipopolysaccharide (LPS) or treated with LPS plus minocycline (LPSMC), and the effects of conditioned media on NPC apoptosis and differentiation were studied. The results showed that, compared with LPS treatment group, the microglia conditioned media of LPSMC treatment group resulted in a significantly lower apoptotic rate of NPCs, and increased the neuronal differentiation of NPCs. This suggested that minocycline might inhibit the negative effects of microglia on NPCs, and have the potential to support the survival and neuronal differentiation of transplanted NPCs for SCI.


Assuntos
Apoptose/efeitos dos fármacos , Microglia/efeitos dos fármacos , Minociclina/farmacologia , Células-Tronco Neurais/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Animais , Diferenciação Celular , Proliferação de Células , Sobrevivência Celular , Células Cultivadas , Meios de Cultivo Condicionados , Relação Dose-Resposta a Droga , Lipopolissacarídeos/farmacologia , Microglia/citologia , Microglia/fisiologia , Células-Tronco Neurais/citologia , Neurônios/citologia , Ratos , Ratos Sprague-Dawley
13.
Acta Crystallogr C ; 63(Pt 7): m341-2, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17609562

RESUMO

The terephthalate dianion and the bis(imidazolyl)benzene ligand of the title compound, {[Zn(C(8)H(4)O(4))(C(20)H(14)N(4))].C(2)H(6)O}(n), each bridges two adjacent zinc centers, resulting in a layer-type coordination polymer; the zinc center shows tetrahedral coordination. The disordered ethanol solvent molecules occupy the spaces between the layers and are hydrogen bonded to the layers. The two symmetry-independent dianions lie on different inversion sites.

14.
J Gene Med ; 9(2): 107-21, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17256801

RESUMO

BACKGROUND: Many clinical trials show that DNA vaccine potency needs to be greatly enhanced. We have reported that the N-terminal fragment of glycoprotein 96 (gp96) is able to produce an adjuvant effect for production of cytotoxic T-lymphocytes (CTLs) with hepatitis B virus (HBV)-specific peptides. Here, we report a new strategy for HBV DNA vaccine design using a partial gp96 sequence. MATERIALS AND METHODS: We linked the N-terminal 1-355aa (N355) of gp96 to HBV genes encoding for structural proteins, the major S and middle S2S envelope proteins and the truncated core HBcAg (1-149aa). ELISPOT, tetramer staining and intracellular IFN-gamma assay were performed to analyze the induced cellular immune responses of our DNA constructs in BALB/c mice and HLA-A2 transgenic mice. The relative humoral immune responses were analyzed in different IgG isotypes. RESULTS: The fusion genes induced 2- to 6-fold higher HBV-specific CD8(+) T cells as compared to the antigens alone. There was an approximate 10-fold decrease in the humoral immune responses with fusion genes based on HBV envelope proteins. Interestingly, the decreased humoral immune responses were not observed when antigens and plasmid encoding N355 were co-delivered. However, an approximate 20-fold higher antibody level was induced when linking N355 to a truncated HBcAg. Immunization by intramuscular injection resulted in predominantly IgG2a antibodies, which indicated that these vaccines preferentially prime Th1 responses. CONCLUSIONS: We constructed highly immunogenic fusions by linking the N-terminal fragment of gp96 to HBV antigens. Our results imply that the N-terminal fragment of gp96 may be used as a molecular adjuvant to enhance the potency of DNA vaccines.


Assuntos
Antígenos de Neoplasias/genética , Antígenos da Hepatite B/genética , Antígenos da Hepatite B/imunologia , Vacinas contra Hepatite B/genética , Vacinas contra Hepatite B/imunologia , Animais , Antígenos de Neoplasias/imunologia , Feminino , Citometria de Fluxo , Vírus da Hepatite B/imunologia , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Transgênicos , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Células Th1/imunologia , Vacinas de DNA/genética , Vacinas de DNA/imunologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA