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1.
ACS Nano ; 2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33565861

RESUMO

Materials with low density, exceptional thermal and corrosion resistance, and ultrahigh mechanical and electromagnetic interference (EMI) shielding performance are urgently demanded for aerospace and military industries. Efficient design of materials' components and microstructures is crucial yet remains highly challenging for achieving the above requirements. Herein, a strengthened reduced graphene oxide (SrGO)-reinforced multi-interfacial carbon-silicon carbide (C-SiC)n matrix (SrGO/(C-SiC)n) composite is reported, which is fabricated by depositing a carbon-strengthening layer into rGO foam followed by alternate filling of pyrocarbon (PyC) and silicon carbide (SiC) via a precursor infiltration pyrolysis (PIP) method. By increasing the number of alternate PIP sequences (n = 1, 3 and 12), the mechanical, electrical, and EMI shielding properties of SrGO/(C-SiC)n composites are significantly increased. The optimal composite exhibits excellent conductivity of 8.52 S·cm-1 and powerful average EMI shielding effectiveness (SE) of 70.2 dB over a broad bandwidth of 32 GHz, covering the entire X-, Ku-, K-, and Ka-bands. The excellent EMI SE benefits from the massive conduction loss in highly conductive SrGO skeletons and polarization relaxation of rich heterogeneous PyC/SiC interfaces. Our composite features low density down to 1.60 g·cm-3 and displays robust compressive properties (up to 163.8 MPa in strength), owing to the uniformly distributed heterogeneous interfaces capable of consuming great fracture energy upon loadings. Moreover, ultrahigh thermostructural stability (up to 2100 °C in Ar) and super corrosion resistance (no strength degradation after long-term acid and alkali immersion) are also discovered. These excellent comprehensive properties, along with ease of low-cost and scalable production, could potentially promote the practical applications of the SrGO/(C-SiC)n composite in the near future.

2.
J Nanosci Nanotechnol ; 21(2): 1054-1060, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33183443

RESUMO

This article explores the role of lysin nanocarriers in inducing apoptosis of human hepatocellular carcinoma cells and the possible molecular mechanisms. Cytotoxicity tests were performed in human fibroblast cell line MRC-5. Anti-cancer activity was tested in liver cancer cell lines HepG2 and HCCLM3. The results show that nanocarriers have a targeting effect on cancer cells, have high safety, and are good delivery vehicles for drugs. In this paper, the stability of lycopene and its degradation in aqueous solutions at different temperatures were studied, and the structure and mechanism of degradation products were determined. A new type of mesoporous silica nanocarrier was synthesized as a delivery carrier of lysin and its derivatives, which has a targeting effect on cancer cells and has a slow-release effect. Surface modification can improve circulation time and stability for future resistance in vivo. The cancer experiment laid the foundation. The results showed that the lysin nanocarriers inhibited the proliferation of HepG2 and HCCLM3 human liver cancer cells in a dependent manner. After the lysin nanocarriers acted on HepG2 human hepatocellular carcinoma cells for 48 h, the cell apoptosis rate was significantly increased by flow cytometry analysis. The carrier can significantly increase the levels of reactive oxygen species and malondialdehyde, and reduce the content of reduced glutathione and superoxide dismutase. At the same time, the lysin nanocarrier can down-regulate the expression of Nrf2 and HO-1 proteins, and inhibit the occurrence of Nrf2 Nuclear displacement. The lycopene nanocarrier inhibits the proliferation of HepG2, HCCLM3 human liver cancer cells, induces apoptosis, regulates the oxidative stress response in the cell, and regulates the Nrf2/AREE antioxidant signaling pathway, thereby promoting tumor cell apoptosis.

3.
Arch Med Sci ; 16(5): 1104-1110, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32863999

RESUMO

Introduction: In recent years, an increasing number of studies have revealed the possible prognostic significance of Golgi protein 73 (GP73) in hepatocellular carcinoma (HCC), but the results are still controversial. Therefore, we performed a meta-analysis to explore the possible correlation between GP73 and prognostic value in HCC. Material and methods: Relevant publications were searched for in PubMed, EMBASE, Cochrane Library and the Chinese Biomedical Literature Database up to March 2018. Odds ratios (ORs) or hazard ratios (HRs) and 95% confidence intervals (CI) of eligible studies were assessed by either fixed-effect or random effects models. Publication bias analysis was also performed to assess the reliability of the meta-analysis results. Results: In total, 9 studies including 1292 patients with HCC were included and analysed systematically in the study. The results indicated that GP73 overexpression was significantly associated with later tumour stage, higher tumour grade and poor overall survival (OS). Combined analysis of three studies showed no statistical correlation between high GP73 expression and disease-free survival (DFS). Subgroup analyses were also performed to illustrate the relationship between high GP73 expression and OS. Conclusions: The meta-analysis suggested that overexpression of GP73 may be associated with poor prognosis in HCC and may also have a predictive role for HCC invasion and metastasis.

4.
J Colloid Interface Sci ; 579: 463-469, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32622095

RESUMO

TiO2 microtubes with tunable wall thickness have been synthesized by a one-step electrospinning method linked with a calcination process. The wall thickness of TiO2 microtubes can be easily tuned by altering the dosage of liquid paraffin. The influence of the thickness on the light-harvesting ability and separation efficiency of the photogenerated carriers was studied using ultraviolet-visible (UV-vis) diffuse reflectance spectroscopy, photoluminescence emission spectroscopy, and photocurrent density measurements. Results show that TiO2 microtubes with an appropriate thickness exhibit enhanced light scattering effect, UV-vis light-harvesting ability, charge separation efficiency, and photocatalytic performance. The degradation rates of rhodamine B and 2,4-dinitrophenol by using TiO2 microtubes synthesized at a dosage of 0.14 g/mL liquid paraffin are 99.9% within 60 min and 97.8% within 40 min, respectively, which are higher than most of the reported values. All these results suggest that our work provides an ideal strategy for adjusting the wall thickness of TiO2 microtubes and new approach to enhance the photocatalytic performance of TiO2.

5.
ACS Appl Mater Interfaces ; 12(22): 24845-24854, 2020 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-32374583

RESUMO

In this work, we prepared flexible carbon-fiber/semimetal Bi nanosheet arrays from solvothermal-synthesized carbon-fiber/Bi2O2CO3 nanosheet arrays via a reductive calcination process. The flexible carbon-fiber/semimetal Bi nanosheet arrays can function as photocatalysts and photoelectrocatalysts for 2,4-dinitorphenol oxidation. Compared with carbon-fiber/Bi2O2CO3 nanosheet arrays, the newly designed flexible carbon-fiber/semimetal Bi nanosheet arrays show enhanced ultraviolet-visible (UV-vis) light absorption efficiency and photocurrent, photocatalytic, and photoelectrocatalytic activities. Photocatalytic analyses indicate that the surface plasmon resonance (SPR) of semimetal Bi occurs under solar-simulated light irradiation during the photocatalytic process. The carbon-fiber traps the hot electrons exerted from the SPR of semimetal Bi and creates holes in the semimetal Bi nanosheets, which boosts the photocatalytic activity of the carbon fiber through plasmonic sensitization. Both photocatalytic experiments and density functional theory (DFT) calculations indicate that the electrons transferred to the carbon fiber and the holes created in semimetal Bi contribute to the formation of •O2- and •OH, respectively. The synergistic effect between electrocatalysis and photocatalysis under the solar-simulated light results in almost complete degradation of 2,4-dinitorphenol during the photoelectrocatalytic process. This work realizes a non-noble-metal plasmonic catalyst and provides a new avenue for the commercialization of photocatalysis and photoelectrocatalysis using the separable and recyclable carbon-fiber/semimetal Bi nanosheet arrays in the environment-related field.

6.
J Colloid Interface Sci ; 574: 174-181, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32311539

RESUMO

Potassium-ion batteries (KIBs) have becoming a prospective energy storage technique, due to the abundant potassium resources in the earth crust, approximate redox potential and similar electrochemical behavior of potassium and lithium. However, the insufficient capacity, poor stability and volume expansion of electrode materials during charge and discharge are main factors restricting the further development of KIBs. This work reports an amorphous carbon coated SnO2 nanohseets on hard carbon hollow spheres (AC/SnO2@HCHS) anode with enhanced potassium storage performance. The HCHS acts as a carrier for SnO2 nanosheets, providing high electrical conductivity and stable skeleton. The self-assembled SnO2 nanosheets with high surface area ensures sufficient contact with the electrolyte. Amorphous carbon wrapping can not only relieve SnO2 volume expansion but also provide surface-induced capacitive capacity. As a consequence, the AC/SnO2@HCHS anode presents excellent potassium-ion storage performance with high discharge capacity of 346 mAh g-1 at 0.1 A g-1 over 200 cycles, ultra-long cycling lifetime and outstanding rate capability (236 mAh g-1 at 1 A g-1 over 1000 cycles).

7.
J Colloid Interface Sci ; 566: 427-433, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32018183

RESUMO

Suitable anode materials for potassium ion batteries (KIBs) with high capacity, good reversibility and stable cycling performances are still in large demand. Here, flexible N doped carbon/bubble-like MoS2 core/sheath framework (MoS2/NCS) is prepared as an anode material for potassium ion batteries. The N doped carbon sponge (NCS) skeleton with good conductivity and high surface area guarantees superior rate capability and high stability of MoS2/NCS anode. The chemical bonds (CMo) firmly bridge MoS2 and NCS together, which further ensures MoS2/NCS stable cycling performance. More importantly, volume expansion is greatly buffered during cycling by this unique structure: the voids between bubble-like MoS2 sheath and NCS core can effectively buffer volume expansion generated during potassium intercalation/deintercalation; the enlarged interlayer spacing contribute more space to buffer volume change; the ultrathin nanosheets can shorten the charge diffusion distance and buffer volume change. As a consequence, MoS2/NCS delivers a capacity of 374 mAh g-1 over 200 cycles at 50 mA g-1. Even at 1000 mA g-1, a capacity of 212 mAh g-1 can still be obtained over 1000 cycles. We believe this MoS2/NCS structure will highlight the potential of MoS2 in practical KIBs applications.

8.
Toxicology ; 433-434: 152411, 2020 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-32081641

RESUMO

OBJECTIVE: Protein glycosylation is involved in immunological recognition and immune cell activation. The role of O-glycosylation in Concanavalin A (Con A)-induced autoimmune hepatitis (AIH) was elucidated in the present study. METHODS: Mice were intravenously injected with Con A (10 mg/kg) to establish an AIH mouse model. Here, 24 h prior to administration of Con A, experimental mice were intragastrically administrated with O-glycosylation inhibitor (benzyl-α-GalNAc) at doses of 1 and 5 mg/kg, respectively, while control mice were administrated with the same volume of saline. Before and after administration of Con A for 6 and 12 h, mice were sacrificed and their plasma and livers were collected to score liver injury. Peripheral blood, spleen, and thymus were collected for flow cytometry analysis. The expression levels of neutrophilic alkaline phosphatase-3 (NALP3) and NALP6 in liver were evaluated as well. RESULTS: Pre-treatment with benzyl-α-GalNAc increased the serum transaminase levels and induced more infiltration and necrosis in livers of Con A administrated mice. The levels of some pro-inflammation cytokines also increased in administrated mice. In addition, pretreatment with benzyl-α-GalNAc up-regulated the expression levels of NALP3 and NALP6. And benzyl-α-GalNAc inhibited the levels of apoptosis of thymus cells and influenced activation of T cells in peripheral blood and spleen of Con A administrated mice, especially that accelerated the physiological progression of CD4+CD25-CD69+ subset. CONCLUSION: The present research demonstrated that benzyl-α-GalNAc aggravated Con A-induced AIH, and the role of the O-glycosylation inhibitor as the aggravation may be related to regulation of the levels of cytokines, as well as influencing proliferation of T cells.


Assuntos
Acetilgalactosamina/análogos & derivados , Compostos de Benzil/toxicidade , Concanavalina A/toxicidade , Citocinas/metabolismo , Hepatite Autoimune/fisiopatologia , Linfócitos T/imunologia , Acetilgalactosamina/administração & dosagem , Acetilgalactosamina/toxicidade , Animais , Apoptose/efeitos dos fármacos , Compostos de Benzil/administração & dosagem , Proliferação de Células/efeitos dos fármacos , Concanavalina A/administração & dosagem , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Glicosilação/efeitos dos fármacos , Hepatite Autoimune/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fatores de Tempo
9.
Gene ; 729: 144233, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31759980

RESUMO

Collagen ß (1-O) galactosyltransferase 1 (GLT25D1) has been reported to transfer galactose to hydroxylysine residues via ß (1-O) linkages in collagen. However, the role of Glt25d1 in liver fibrogenesis is still unknow. Recently, we generated a Glt25d1 knockout mouse to elucidate the role of Glt25d1 in vivo. However, we found that complete deletion of the Glt25d1 gene resulted in embryonic lethality at E11.5. Histopathological analysis revealed that dysplasia in Glt25d1-/- labyrinth with defects of the vascular network. Immunohistochemical showed that the decrease in proliferation of Glt25d1-/- liver and the developing central nervous system (CNS). The role of Glt25d1 in liver fibrogenesis was explored by Glt25d1+/- mice. Glt25d1+/- mice and wild-type (WT) mice were injected intraperitoneally with the same dose of CCl4. The higher level of serum alanine aminotransferase was observed in Glt25d1+/- mice. Reverse transcription-quantitative polymerase chainreaction demonstrated that the mRNA expression levels of the inflammatory cytokines such as, Tnf-α, Cxcl-1 and Mcp-1, showed a significantly increase in CCl4-treated Glt25d1+/- mice. Collagen-I, collagen-III and α-SMA transcripts accumulation was markedly increased in the Glt25d1+/- mice. However, Masson's trichrome staining revealed a trend to decrease in the ECM proteins deposition of Glt25d1+/- liver. Immunohistochemistry and Western blots revealed that the protein expression of Collagen-III was reduced and a trend to a decrease in collagen-I was observed in the Glt25d1+/- liver compared with those of WT mice. Our results demonstrate that Glt25d1 knockout results in embryonic lethality and down-regulation of Glt25d1 may inhibit collagen secretion during liver fibrogenesis.


Assuntos
Colágeno/metabolismo , Galactosiltransferases/metabolismo , Cirrose Hepática/metabolismo , Alanina Transaminase/metabolismo , Animais , Colágeno/antagonistas & inibidores , Regulação para Baixo , Matriz Extracelular/metabolismo , Feminino , Galactosiltransferases/genética , Glicosilação , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática/genética , Cirrose Hepática/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Gravidez
10.
J Colloid Interface Sci ; 588: 84-93, 2020 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-33388589

RESUMO

Carbon fibers (CFs) show great potential for high-performance supercapacitors in miniature electronics fields, where high energy density and long cycling life are required. However, superior combination of these two attributes in CF-based supercapacitors still presents a long-standing challenge. Herein, straight carbon nanotubes (CNTs) with radial orientation and high chemical/physical stability are served as nanoscale conductive skeletons on CFs for supporting the polyaniline (PANI)/SnS2. The SnS2 with nanoflower-like features significantly increases the specific capacitance and specific surface area (SSA); furthermore, the PANI nanolayers covered on SnS2 petals enable secondary specific capacitance enhancement and inhibition of volume expansion of SnS2 during charging/discharging processes. Benefiting from these structural merits, the resultant PANI/SnS2@CNTs/CFs hybrids exhibit high SSA (2732.5 m2 g-1), high specific capacitance (891 F g-1 at 20 mV s-1) and excellent cycling stability (83.8% after 6000 cycles at 2 A g-1). Moreover, the hybrids deliver a superior energy density of 38.7 W h kg-1 at a power density of 1 kW kg-1 and outstanding performance stability, which should prove to be vastly advantageous as compared to the reported CF-based supercapacitors. Our work puts forward a new thinking of rational construction of high-performance CF-based supercapacitors that can be used in practical energy storage devices.

11.
Drug Des Devel Ther ; 13: 3579-3589, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31802846

RESUMO

Purpose: Diammonium glycyrrhizinate (DG) is a replacement for glycyrrhizic acid, which is used as a hepatic protector in clinical practice for most liver diseases. The potential role of immune response during autoimmune hepatitis-induced by concanavalin A (Con A)-remains to be elucidated. Methods: C57BL/6J mice were treated with two different doses of DG (75 and 200 mg/kg) 2 hrs before administering Con A. The mice were sacrificed after administering Con A for 0, 6, and 24 hrs. Liver damage grade and serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and total bilirubin levels were evaluated. The expression level of cleaved-caspase 3 in liver was detected by Western blotting. Inflammatory cytokines such as tumor necrosis factor α (TNF-α), interleukin-6 (IL-6), and interferon γ (IFN-γ) in liver were detected by RT-PCR. Thymus, peripheral blood, spleen, and liver tissues were collected to analyze the percentages of NKT cells, subsets of CD4+CD25-CD69+ and CD8+CD69+ T cells, and subsets of regulatory T cells (Tregs). Results: Our results revealed that DG pre-treatment significantly decreased the serum ALT and AST levels and improved the histological damage in Con A-induced autoimmune liver injury. Pre-treatment with DG down-regulated the inflammatory cytokines upon challenge with Con A. The DG pre-treatment inhibited the apoptosis of T lymphocytes in the thymus. Further, it effectively suppressed the proliferation of CD4+CD25-CD69+ and CD8+CD69+ subsets in the peripheral blood and spleen. In addition, the DG pretreatment significantly downregulated the frequency of NKT cells, while upregulating the frequency of Tregs in the liver. Conclusion: We believe that the potential protective effect of DG against Con A-induced hepatitis may be partially attributed to its inhibitory activities on inflammatory cytokines in the livers, lymphocyte apoptosis in the thymus, NKT cells proliferation, and activation of CD8+T cells; further, there may also be a possibility of DC promoting Tregs proliferation.


Assuntos
Anti-Inflamatórios/farmacologia , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Ácido Glicirrízico/farmacologia , Hepatite Autoimune/tratamento farmacológico , Células T Matadoras Naturais/efeitos dos fármacos , Linfócitos T Reguladores/efeitos dos fármacos , Animais , Proliferação de Células/efeitos dos fármacos , Doença Hepática Induzida por Substâncias e Drogas/patologia , Concanavalina A , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Hepatite Autoimune/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Estrutura Molecular , Células T Matadoras Naturais/patologia , Relação Estrutura-Atividade , Linfócitos T Reguladores/patologia
12.
BMC Gastroenterol ; 19(1): 101, 2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-31226942

RESUMO

BACKGROUND: The preventive effects of antiviral therapy to reduce rebleeding rate in patients with hepatitis B-related cirrhosis undergoing endoscopic treatment have not yet been reported. METHODS: In this retrospective cohort study, 1139 patients with chronic hepatitis B with first acute variceal bleeding after endoscopic therapy from September 2008 to December 2017 were included. Among them, 923 who received and 216 who did not receive antiviral therapy were followed up for rebleeding. Cumulative rebleeding rate was calculated using the Kaplan-Meier method. Univariate and multivariate logistic regression analyses were performed to estimate the effects of antiviral therapy on rebleeding risk. The propensity score matched method and inverse probability of treatment weighting analysis were used to calculate the rebleeding rate between the antiviral and non-antiviral groups. RESULTS: The rebleeding rates were 40.5, 60.7, 72.6, and 89.2% in antiviral group at 1, 2, 3, and 5 years, respectively. The corresponding rebleeding rates in the non-antiviral group were 54.2, 72.4, 84.4, and 93.3%, respectively. The multivariate logistic regression analysis revealed that antiviral therapy was an independent protective factor associated with rebleeding. CONCLUSION: Antiviral treatment significantly reduced rebleeding rate in patients with HBV-related cirrhosis who received endoscopic treatment after the first variceal bleeding.


Assuntos
Antivirais/uso terapêutico , Endoscopia/efeitos adversos , Varizes Esofágicas e Gástricas/prevenção & controle , Hemorragia Gastrointestinal/prevenção & controle , Vírus da Hepatite B , Hepatite B Crônica/complicações , Cirrose Hepática/cirurgia , Complicações Pós-Operatórias/prevenção & controle , Doença Aguda , Varizes Esofágicas e Gástricas/epidemiologia , Varizes Esofágicas e Gástricas/virologia , Feminino , Hemorragia Gastrointestinal/epidemiologia , Hemorragia Gastrointestinal/virologia , Hepatite B Crônica/virologia , Humanos , Estimativa de Kaplan-Meier , Cirrose Hepática/virologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/virologia , Pontuação de Propensão , Fatores de Proteção , Recidiva , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
13.
Dig Liver Dis ; 51(8): 1166-1171, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30723020

RESUMO

BACKGROUND AND AIMS: A predictive algorithm for survival is urgently needed in clinical practice. This study aimed to establish an algorithm to predict long-term survival in chronic hepatitis B (CHB) patients with hepatic cirrhosis and variceal bleeding after endoscopic therapy. METHODS: This was a retrospective study in which 603 patients who followed-up for three years were randomly assigned into a training cohort and a validation cohort in a 2:1 ratio. A new score model was devised based on the result of Cox regression analysis in the training cohort, and was verified in the validation cohort. RESULTS: A prediction score model composed of age, neutrophil-lymphocyte ratio, gamma-glutamyl transpeptidase and MELD score was established. The score ranged from 0 to 11. Areas under the ROC curve of the score were 0.821 (p < 0.001, 95% CI: 0.769-0.873) and 0.827 (p < 0.001, 95% CI: 0.753-0.900) in the training cohort and validation cohort, respectively. Scores 0-4 and 5-11 identified patients as low-risk and high-risk categories, respectively. The cumulative 3-year survival rate was significantly higher in the low-risk group than in the high-risk group (p < 0.001). CONCLUSION: The new score model can be used to predict long-term survival in CHB patients with hepatic cirrhosis and variceal bleeding after endoscopic therapy.


Assuntos
Endoscopia do Sistema Digestório/métodos , Varizes Esofágicas e Gástricas/complicações , Hemorragia Gastrointestinal/etiologia , Hemorragia Gastrointestinal/terapia , Cirrose Hepática/complicações , Adulto , Algoritmos , Antivirais/uso terapêutico , China , Feminino , Hemorragia Gastrointestinal/mortalidade , Hepatite B Crônica/complicações , Hepatite B Crônica/terapia , Humanos , Cirrose Hepática/mortalidade , Masculino , Pessoa de Meia-Idade , Prognóstico , Curva ROC , Distribuição Aleatória , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida
14.
Front Immunol ; 9: 2089, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30356792

RESUMO

Post-translational modifications such as glycosylation play an important role in the functions of homeostatic proteins, and are critical driving factors of several diseases; however, the role of glycosylation in autoimmune hepatitis is poorly understood. Here, we established an O-GlcNAc glycosylation-deficient rat model by knocking out the Eogt gene by TALEN-mediated gene targeting. O-GlcNAc glycosylation deficiency overtly aggravated liver injury in concanavalin-A induced autoimmune hepatitis, and delayed self-recovery of the liver. Furthermore, flow cytometry analysis revealed increased CD4+ T cell infiltration in the liver of rats with O-GlcNAc glycosylation deficiency, and normal differentiation of regulatory T cells (Tregs) in the liver to inhibit T cell infiltration could not be activated. Moreover, in vitro experiments showed that O-GlcNAc glycosylation deficiency impaired Treg differentiation to inhibit the Notch signaling pathway in CD4+ T cells. These finding indicate that O-GlcNAc glycosylation plays a critical role in the activation of Notch signaling, which could promote Treg differentiation in the liver to inhibit T cell infiltration and control disease development in autoimmune hepatitis. Therefore, this study reveals a regulatory role for glycosylation in the pathogenesis of autoimmune hepatitis, and highlights glycosylation as a potential treatment target.


Assuntos
Acetilglucosamina/metabolismo , Fígado/patologia , N-Acetilglucosaminiltransferases/metabolismo , Receptores Notch/metabolismo , Linfócitos T Reguladores/imunologia , Animais , Diferenciação Celular , Concanavalina A , Modelos Animais de Doenças , Técnicas de Inativação de Genes , Glicosilação , Hepatite Autoimune , Ativação Linfocitária , N-Acetilglucosaminiltransferases/genética , Processamento de Proteína Pós-Traducional , Ratos , Ratos Sprague-Dawley , Transdução de Sinais
15.
Mol Med Rep ; 18(4): 3611-3618, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30132521

RESUMO

Collagen ß (1­O) galactosyltransferase 1 (GLT25D1) has been reported to transfer galactose to hydroxylysine residues via ß (1­O) linkages in collagen. The present study investigated the function of the collagen galactosyltransferase activity of GLT25D1 against carbon tetrachloride (CCl4)­induced acute liver injury in vitro. Glt25d1+/­ mice and wild­type (WT) mice were injected intraperitoneally with the same dose of CCl4. The grade of hepatic injury and the extent of hepatocyte necrosis in the acute phase were assessed 48 h following CCl4 injection. Hepatocyte necrosis was evaluated by histological examination and by serum alanine aminotransferase and aspartate aminotransferase levels, which were higher in the Glt25d1+/­ mice compared with those in the WT mice. Reverse transcription­quantitative polymerase chain reaction was performed, and the results demonstrated that the mRNA expression levels of inflammatory cytokines, including tumor necrosis factor­α and interleukin­6 were significantly increased in the Glt25d1+/­ mice. Furthermore, western blot analyses were performed, and the results demonstrated that the protein levels of cleaved caspase­3 and ­9 were also markedly increased in the Glt25d1+/­ liver, indicating that hepatocyte apoptosis was induced. Additionally, the expression levels of transforming growth factor (TGF)­ß1 and phosphorylated small mothers against decapentaplegic (Smad)2 were markedly upregulated, indicating activation of the TGF­ß1/Smad2 signaling pathway during CCl4­induced acute liver injury in Glt25d1+/­ mice. CCl4 administration also resulted in severe damage to Glt25d1+/­ primary hepatocytes in vitro. Taken together, the downregulation of Glt25d1 deteriorated CCl4­induced liver injury in mice, which may involve triggering inflammatory responses, apoptosis and TGF­ß1/Smad2 signaling pathway activation.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/genética , Regulação para Baixo , Transdução de Sinais , Proteína Smad2/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Animais , Tetracloreto de Carbono , Células Cultivadas , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Feminino , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Hepatócitos/patologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Camundongos , Camundongos Knockout
16.
Medicine (Baltimore) ; 97(24): e11130, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29901640

RESUMO

BACKGROUND: Glypican-3 (GPC3) has been widely recognized in the progression of liver tumors for several years. The relationship between overexpression of GPC3 and the poorer prognosis of patients with hepatocellular carcinoma (HCC) was performed by 2 meta-analyses. However, there were also some latest literatures that indicated different conclusions distinctly. It is necessary for us to carry out a meta-analysis by adding the latest data from current studies to explore the correlation between GPC3 and prognostic value in HCC. METHODS: We conducted a meta-analysis including a total of 14 studies to assess the potential prognostic significance of GPC3 expression for overall survival (OS) and disease-free survival (DFS). The expression of GPC3 was assessed by immunohistochemistry. RESULTS: Fourteen studies with 2364 patients were incorporated in the meta-analysis. The combined hazard ratios (HRs) revealed that the overexpression of GPC3 could forecast a poor OS [n = 2233 in 12 studies, HR = 1.40, 95% confidence interval (95% CI): 1.07-1.85, Z = 2.42, P = .02] and DFS (n = 1308 in 10 studies, HR = 1.61, 95% CI: 1.13-2.30, Z = 2.63, P = .008) in HCC patients. Subgroup treated by hepatectomy indicated that the pooled HR of OS was 1.43 (95% CI: 1.01-2.01, P = .04) and the combined HR of DFS was 1.59 (95% CI: 1.09-2.31, P = .02). The pooled odds ratios (ORs) showed that high GPC3 expression was also extensively associated with worse tumor differentiation, later tumor stage, presence of vascular invasion, and hepatitis B virus (HBV) infection. Subgroup analyses for GPC3 on HCC OS based on the studies categorized by regions, follow-up period, and sample size were also conducted. CONCLUSION: The meta-analysis indicated that overexpression of GPC3 was significantly associated with poor prognosis in patients with HCC.


Assuntos
Carcinoma Hepatocelular/metabolismo , Glipicanas/metabolismo , Neoplasias Hepáticas/metabolismo , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Progressão da Doença , Humanos , Imuno-Histoquímica , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Prognóstico , Taxa de Sobrevida
17.
Cell Immunol ; 331: 9-15, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29748000

RESUMO

The present study was conducted to characterize the C6orf120 gene, by using C6orf120 gene-deleted rats (C6orf120-/-), to determine its role in the development and severity of autoimmune hepatitis induced by concanavalin A (Con A), as well as the underlying mechanisms. We found that following Con A injection, C6orf120-/- rats were less susceptible to developing autoimmune hepatitis with low levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) post challenge. Additionally, C6orf120 deficiency increased the frequency of cluster of differentiation (CD)4+ CD25+ Forkhead box P3+ regulatory T cells (Tregs) among intrahepatic lymphocytes, splenocytes, peripheral blood mononuclear cells, and CD4+ T in vitro. Moreover, C6orf120 deficiency downregulated interleukin (IL)-1ß, IL-6, tumor necrosis factor alpha-α, interferon-γ and IL-17a secretion in the plasma and liver tissues. Our results indicated that the C6orf120 gene-deleted rats were less susceptible to Con A-induced autoimmune hepatitis, which may be partly related to the increased frequency of Tregs and inhibited secretion of inflammatory cytokines.


Assuntos
Deleção de Genes , Glicoproteínas/genética , Hepatite Autoimune/genética , Linfócitos T Reguladores/metabolismo , Animais , Concanavalina A/toxicidade , Citocinas/metabolismo , Glicoproteínas/deficiência , Hepatite Autoimune/etiologia , Hepatite Autoimune/metabolismo , Mediadores da Inflamação/metabolismo , Leucócitos Mononucleares/metabolismo , Fígado/metabolismo , Fígado/patologia , Masculino , Ratos Sprague-Dawley
18.
Onco Targets Ther ; 10: 4829-4839, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29042794

RESUMO

BACKGROUND AND AIMS: Hepatic resection (HRN) and microwave ablation (MWA) have significant advantages in treating hepatocellular carcinoma; however, it remains unclear which way produces better outcomes. This meta-analysis of cohort studies compared the treatments in terms of effectiveness and safety. METHODS: Six electronic databases (PubMed, Medline, EMBASE, Web of Science, EBSCO, and The Cochrane Library) were retrieved for studies comparing MWA and HRN. The meta-analysis was conducted based on statement of preferred reporting items for systematic reviews and meta-analyses. RESULTS: Nine studies met the inclusion criteria, with a total of 1,480 patients. The overall meta-analysis demonstrated no significant difference in overall survival between the MWA group and the HRN group (HR =0.98, 95% CI =0.76-1.26, P=0.878). There was no difference in disease-free survival between the MWA group and the HRN group (HR =1.16, 95% CI =0.79-1.71, P=0.442). Meanwhile, the meta-analysis demonstrated that MWA was associated with shorter operation time (standardized mean difference [SMD] =-1.37, 95% CI =-1.92 to -0.81, P=0.000), less amount of blood loss in operation (SWD =-1.19, 95% CI =-1.76 to -0.61, P=0.000), and less complications (OR =0.22, 95% CI =0.12-0.40, P=0.000) than HRN. CONCLUSION: In conclusion, our meta-analysis suggests that MWA may be superior to HRN as it is as effective as HRN in terms of overall survival, disease-free survival, tumor recurrence, and is associated with shorter operation time, less amount of blood loss, and fewer complications.

19.
Nat Commun ; 8: 13906, 2017 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-28054546

RESUMO

In emerging optoelectronic applications, such as water photolysis, exciton fission and novel photovoltaics involving low-dimensional nanomaterials, hot-carrier relaxation and extraction mechanisms play an indispensable and intriguing role in their photo-electron conversion processes. Two-dimensional transition metal dichalcogenides have attracted much attention in above fields recently; however, insight into the relaxation mechanism of hot electron-hole pairs in the band nesting region denoted as C-excitons, remains elusive. Using MoS2 monolayers as a model two-dimensional transition metal dichalcogenide system, here we report a slower hot-carrier cooling for C-excitons, in comparison with band-edge excitons. We deduce that this effect arises from the favourable band alignment and transient excited-state Coulomb environment, rather than solely on quantum confinement in two-dimension systems. We identify the screening-sensitive bandgap renormalization for MoS2 monolayer/graphene heterostructures, and confirm the initial hot-carrier extraction for the C-exciton state with an unprecedented efficiency of 80%, accompanied by a twofold reduction in the exciton binding energy.

20.
Sci Rep ; 5: 11662, 2015 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-26111758

RESUMO

The properties of graphene can vary as a function of the number of layers (NOL). Controlling the NOL in large area graphene is still challenging. In this work, we demonstrate a picosecond (ps) laser thinning removal of graphene layers from multi-layered graphene to obtain desired NOL when appropriate pulse threshold energy is adopted. The thinning process is conducted in atmosphere without any coating and it is applicable for graphene films on arbitrary substrates. This method provides many advantages such as one-step process, non-contact operation, substrate and environment-friendly, and patternable, which will enable its potential applications in the manufacturing of graphene-based electronic devices.

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