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1.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 34(3): 318-322, 2020 Mar 15.
Artigo em Chinês | MEDLINE | ID: mdl-32174076

RESUMO

Objective: To investigate the expression and correlation of hypoxia inducible factor 1α (HIF-1α) and autophagy related molecules (Beclin1 and LC3B) in rat nucleus pulposus cells under hypoxia in vitro. Methods: The nucleus pulposus cells were extracted from the nucleus pulposus of healthy adult Sprague Dawley rats and passaged. The 3rd generation cells were identified by HE staining and collagenase type Ⅱ immunofluorescence staining and randomly divided into 4 groups. The cells in group A were cultured for 8 hours under normal oxygen condition (37℃, 5%CO 2, 20%O 2); the cells in group B were cultured for 8 hours under hypoxia condition (37℃, 5%CO 2, 1%O 2); the cells in group C were transfected with HIF-1α-small interfering RNA and cultured for 8 hours under hypoxia condition; and the cells in group D were cultured with autophagy inhibitor 3-MA for 8 hours under hypoxia condition. Western blot and real-time fluorescence quantitative PCR (qRT-PCR) were used to detect the expressions of HIF-1α and autophagy related molecules (Beclin1 and LC3B) in all groups. Results: HE staining of the 3rd generation nucleus pulposus cells showed that the cytoplasm was light pink and the nucleus was blue black, and the collagenase type Ⅱ immunofluorescence staining was positive. Western blot and qRT-PCR results showed that the relative expressions of HIF-1α, Beclin1, and LC3B proteins and genes in group B were significantly higher than those in group A ( P<0.05); the relative expressions of HIF-1α, Beclin1, and LC3B proteins and genes in group C were significantly lower than those in group B ( P<0.05). There was no significant difference in the relative expression of HIF-1α protein and gene between groups B and D ( P>0.05); while the relative expressions of Beclin1 and LC3B proteins and genes in group D were significant lower than those in group B ( P<0.05). Conclusion: Hypoxia can induce the expressions of HIF-1α and autophagy related molecules (Beclin1 and LC3B) in rat nucleus pulposus cells, and HIF-1α in rat nucleus pulposus cells under hypoxia is related to the expression of autophagy related molecules, that is, down-regulation of HIF-1α can significantly reduce the expression of autophagy related molecules, while the down-regulation of autophagy levels under hypoxia has no or little effect on the expression of HIF-1α.

2.
Small ; 15(43): e1902432, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31490636

RESUMO

The further development of high-power sodium-ion batteries faces the severe challenge of achieving high-rate cathode materials. Here, an integrated flexible electrode is constructed by smart combination of a conductive carbon cloth fiber skeleton and N-doped carbon (NC) shell on Na3 V2 (PO4 )3 (NVP) nanoparticles via a simple impregnation method. In addition to the great electronic conductivity and high flexibility of carbon cloth, the NC shell also promotes ion/electron transport in the electrode. The flexible NVP@NC electrode renders preeminent rate capacities (80.7 mAh g-1 at 50 C for cathode; 48 mAh g-1 at 30 C for anode) and superior cycle performance. A flexible symmetric NVP@NC//NVP@NC full cell is endowed with fairly excellent rate performance as well as good cycle stability. The results demonstrate a powerful polybasic strategy design for fabricating electrodes with optimal performance.

3.
J Biol Chem ; 294(30): 11579-11596, 2019 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-31186347

RESUMO

Human telomerase maintains genome stability by adding telomeric repeats to the ends of linear chromosomes. Although previous studies have revealed profound insights into telomerase functions, the low cellular abundance of functional telomerase and the difficulties in quantifying its activity leave its thermodynamic and kinetic properties only partially characterized. Employing a stable cell line overexpressing both the human telomerase RNA component and the N-terminally biotinylated human telomerase reverse transcriptase and using a newly developed method to count individual extension products, we demonstrate here that human telomerase holoenzymes contain fast- and slow-acting catalytic sites. Surprisingly, both active sites became inactive after two consecutive rounds of catalysis, named single-run catalysis. The fast active sites turned off ∼40-fold quicker than the slow ones and exhibited higher affinities to DNA substrates. In a dimeric enzyme, the two active sites work in tandem, with the faster site functioning before the slower one, and in the monomeric enzyme, the active sites also perform single-run catalysis. Interestingly, inactive enzymes could be reactivated by intracellular telomerase-activating factors (iTAFs) from multiple cell types. We conclude that the single-run catalysis and the iTAF-triggered reactivation serve as an unprecedented control circuit for dynamic regulation of telomerase. They endow native telomerase holoenzymes with the ability to match their total number of active sites to the number of telomeres they extend. We propose that the exquisite kinetic control of telomerase activity may play important roles in both cell division and cell aging.

4.
ACS Appl Mater Interfaces ; 10(16): 13598-13605, 2018 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-29634234

RESUMO

Lithium-sulfur batteries (LSBs) are deemed to be among the most prospective next-generation advanced high-energy batteries. Advanced cathode materials fabricated from biological carbon are becoming more popular due to their unique properties. Inspired by the fibrous structure of bamboo, herein we put forward a smart strategy to convert bamboo sticks for barbecue into uniform bamboo carbon fibers (BCF) via a simple hydrothermal treatment proceeded in alkaline solution. Then NiCl2 is used to etch the fibers through a heat treatment to achieve Ni-embedded porous graphitic carbon fibers (PGCF/Ni) for LSBs. The designed PGCF/Ni/S electrode exhibits improved electrochemical performances including high initial capacity (1198 mAh g-1 at 0.2 C), prolonged cycling life (1030 mAh g-1 at 0.2 C after 200 cycles), and improved rate capability. The excellent properties are attributed to the synergistic effect of 3D porous graphitic carbon fibers with highly conductive Ni nanoparticles embedded.

5.
Adv Sci (Weinh) ; 5(3): 1700786, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29593977

RESUMO

Exploring advanced high-rate anodes is of great importance for the development of next-generation high-power lithium-ion batteries (LIBs). Here, novel carbon nanotubes (CNTs)/Li4Ti5O12 (LTO) core/shell arrays on carbon cloth (CC) as integrated high-quality anode are constructed via a facile combined chemical vapor deposition-atomic layer deposition (ALD) method. ALD-synthesized LTO is strongly anchored on the CNTs' skeleton forming core/shell structures with diameters of 70-80 nm the combined advantages including highly conductive network, large surface area, and strong adhesion are obtained in the CC-LTO@CNTs core/shell arrays. The electrochemical performance of the CC-CNTs/LTO electrode is completely studied as the anode of LIBs and it shows noticeable high-rate capability (a capacity of 169 mA h g-1 at 1 C and 112 mA h g-1 at 20 C), as well as a stable cycle life with a capacity retention of 86% after 5000 cycles at 10 C, which is much better than the CC-LTO counterpart. Meanwhile, excellent cycling stability is also demonstrated for the full cell with LiFePO4 cathode and CC-CNTs/LTO anode (87% capacity retention after 1500 cycles at 10 C). These positive features suggest their promising application in high-power energy storage areas.

6.
Small ; 14(16): e1704339, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29573548

RESUMO

High-performance of lithium-ion batteries (LIBs) rely largely on the scrupulous design of nanoarchitectures and smart hybridization of bespoke active materials. In this work, the pine-needle-like Cu-Co skeleton is reported to support highly active Li4 Ti5 O12 (LTO) forming Cu-Co/LTO core-branch arrays via a united hydrothermal-atomic layer deposition (ALD) method. ALD-formed LTO layer is uniformly anchored on the pine-needle-like heterostructured Cu-Co backbone, which consists of branched Co nanowires (diameters in 20 nm) and Cu nanowires (250-300 nm) core. The designed Cu-Co/LTO core-branch arrays show combined advantages of large porosity, high electrical conductivity, and good adhesion. Due to the unique positive features, the Cu-Co/LTO electrodes are demonstrated with enhanced electrochemical performance including excellent high-rate capacity (155 mAh g-1 at 20 C) and noticeable long-term cycles (144 mAh g-1 at 20 C after 3000 cycles). Additionally, the full cell assembled with activated carbon positive electrode and Cu-Co/LTO negative electrode exhibits high power/energy densities (41.6 Wh kg-1 at 7.5 kW kg-1 ). The design protocol combining binder-free characteristics and array configuration opens a new door for construction of advanced electrodes for application in high-rate electrochemical energy storage.

7.
Mediators Inflamm ; 2016: 4927530, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27738386

RESUMO

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease characterized by aberrant T cell immune response. Diffuse proliferative lupus nephritis (LN-IV) is the most common, severe, and active form of lupus nephritis. In this study, we investigated the production of Th1, Th2, and Th17 cytokines in prediction of active form of LN-IV. ProcartaPlex multiplex immunoassays panels were used for detection of serum Th1, Th2, and Th17 cytokines profiling. Th1 and Th17 cytokines (IL-18, IFN-γ, IL-12p70, IL-6, and IL-17A) were considerably expressed in the serum of lupus nephritis IV patients in comparison to the healthy control. However, only IL18 and IL6 were higher in class IV versus class III lupus nephritis. Importantly, the ratios of Th1/Th2 (IL-18/IL-4) and Th17/Th2 (IL-17A/IL-4) were significantly elevated in LN-IV when compared with LN-III, LN-V, and healthy controls. Consistently, the serum cytokines IL-18, IL-17A, and IFN-γ were markedly expressed in LN-IV patient glomeruli and interstitial tissue compared to other classes of LN by IHC. ROC further suggests that IL-18 was a potential marker for LN-IV. The data from our study suggests that the early detection and quantification of these cytokines may help in prediction of active form of LN-IV.


Assuntos
Citocinas/sangue , Células Th1/metabolismo , Células Th17/metabolismo , Células Th2/metabolismo , Adulto , Grupo com Ancestrais do Continente Asiático , Complemento C3/metabolismo , Complemento C4/metabolismo , Feminino , Humanos , Interferon gama/sangue , Interleucina-12/sangue , Interleucina-13/sangue , Interleucina-18/sangue , Interleucina-4/sangue , Interleucina-6/sangue , Lipocalina-2/sangue , Nefrite Lúpica/sangue , Masculino , Pessoa de Meia-Idade , Fator de Necrose Tumoral alfa/sangue
8.
J Immunol Res ; 2015: 848790, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26090502

RESUMO

The long noncoding RNAs (lncRNAs) are RNA transcripts more than 200 nucleotides in length, which do not encode proteins. The lncRNAs are emerging as an important regulator of biological process, such as chromatin remodeling, gene transcription, protein transport, and trafficking through diverse mechanisms. The lncRNAs play crucial role in various multigenetics human diseases including cancers and neurological diseases and currently its role in autoimmune diseases is attracting many researchers. Recent studies have reported that differentiation and activation of immune cells, T cells, B cells, macrophages, and NK cells have correlation with lncRNAs, which have also an essential role in autoimmune diseases such as rheumatoid arthritis and SLE. Therefore, elucidation of the roles of lncRNAs in autoimmunity could be beneficial to understand the pathogenesis of autoimmune diseases. In this review article we attempt to highlight the recent progress regarding lncRNAs studies and summarize its role in autoimmune diseases.


Assuntos
Doenças Autoimunes/genética , Doenças Autoimunes/imunologia , Imunidade/genética , Imunidade/imunologia , RNA Longo não Codificante/genética , RNA Longo não Codificante/imunologia , Animais , Humanos
9.
Int. braz. j. urol ; 40(6): 846-852, Nov-Dec/2014. tab
Artigo em Inglês | LILACS | ID: lil-735980

RESUMO

There is a lack of definitive information regarding the precise indications, implementation, and outcomes of continuous renal replacement therapy (CRRT) for the treatment of critically ill children. Six children (three boys, three girls) aged from 3 days to 8 years, all of whom had multiple organ failure, were submitted to bedside CRRT using M60 filter membranes. Modified Port carbonate formula was used and clotting time was maintained between 20 and 30 minutes. Activated partial thromboplastin time was 1.5- to 2-fold normal. One patient discontinued treatment due to family decision. Marked improvements were seen in the remaining five patients, including normalization of blood urea nitrogen and creatinine levels, stabilization of electrolytes, and improvements in markers of organ function. Of note, one patient (a six-year-old male) underwent the treatment for 241 hours. All five patients were subsequently discharged and recovered uneventfully. CRRT is effective for the management of children who are critically ill due to multiple organ failure.


Assuntos
Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Insuficiência de Múltiplos Órgãos/terapia , Terapia de Substituição Renal/métodos , Lesão Renal Aguda/terapia , Cuidados Críticos , Estado Terminal , Unidades de Terapia Intensiva Pediátrica , Insuficiência de Múltiplos Órgãos/fisiopatologia , Fatores de Tempo , Resultado do Tratamento
10.
Int Braz J Urol ; 40(6): 846-52, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25615255

RESUMO

There is a lack of definitive information regarding the precise indications, implementation, and outcomes of continuous renal replacement therapy (CRRT) for the treatment of critically ill children. Six children (three boys, three girls) aged from 3 days to 8 years, all of whom had multiple organ failure, were submitted to bedside CRRT using M60 filter membranes. Modified Port carbonate formula was used and clotting time was maintained between 20 and 30 minutes. Activated partial thromboplastin time was 1.5- to 2-fold normal. One patient discontinued treatment due to family decision. Marked improvements were seen in the remaining five patients, including normalization of blood urea nitrogen and creatinine levels, stabilization of electrolytes, and improvements in markers of organ function. Of note, one patient (a six-year-old male) underwent the treatment for 241 hours. All five patients were subsequently discharged and recovered uneventfully. CRRT is effective for the management of children who are critically ill due to multiple organ failure.


Assuntos
Insuficiência de Múltiplos Órgãos/terapia , Terapia de Substituição Renal/métodos , Lesão Renal Aguda/terapia , Criança , Pré-Escolar , Cuidados Críticos , Estado Terminal , Feminino , Humanos , Lactente , Recém-Nascido , Unidades de Terapia Intensiva Pediátrica , Masculino , Insuficiência de Múltiplos Órgãos/fisiopatologia , Fatores de Tempo , Resultado do Tratamento
11.
Int J Biol Sci ; 9(1): 94-107, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23355795

RESUMO

BACKGROUND/AIMS: Accumulation of advanced glycation end-products, the well-recognized pro-inflammatory molecules, has been detected in renal tissues including tubules. The aim of the present study was to investigate the role of advanced glycation end-products modified low density lipoprotein (AGE-LDL) in inflammatory cytokines production in human proximal tubular epithelial cells and the underlying mechanism. METHODS: The Interleukin-6 (IL-6) and Interleukin-8 (IL-8) production was examined by real-time PCR and ELISA. The expression of Toll-like receptor 2 and 4 (TLR2/4) was detected by flow cytometry and western blot. The interaction of TLR2/4 with AGE-LDL was examined by co-immunoprecipitation assay. The involvement of MyD88 and the downstream molecules in inflammatory cytokines production was examined by siRNA and pharmacologic inhibitors, respectively. RESULTS: AGE-LDL interacted with TLR2 and TLR4. TLR4 siRNA showed stronger inhibition on AGE-LDL-induced IL-6 and IL-8 production than that of TLR2 siRNA. Silencing MyD88, but not TRIF, inhibited AGE-LDL-induced IL-6 and IL-8 production. AGE-LDL stimulation led to phosphorylation of JNK, p38, Akt and the p65 subunit of nuclear factor-κB (NF-κB). Pharmacologic inhibitor of Akt suppressed AGE-LDL-induced activation of NF-κB, but the inhibitor of JNK, p38 or ERK1/2 had no effect. Blocking MyD88, p38, JNK, Akt or NF-κB attenuated AGE-LDL-triggered IL-6 production. CONCLUSION: AGE-LDL induced IL-6 and IL-8 production via TLR2/4-MyD88-dependent pathway in tubular epithelial cells. These data suggest that activation of TLRs signaling in tubular epithelial cells by AGE-LDL might be a novel mechanism for the tubulointerstitial inflammation.


Assuntos
Citocinas/metabolismo , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Túbulos Renais/citologia , Receptor 4 Toll-Like/metabolismo , Linhagem Celular , Produtos Finais de Glicação Avançada/metabolismo , Humanos , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Lipoproteínas LDL , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Receptor 2 Toll-Like/genética , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/genética
12.
Artigo em Inglês | MEDLINE | ID: mdl-19478438

RESUMO

Hibiscus chlorotic ringspot virus (HCRSV) is a positive-sense monopartite single-stranded RNA virus that belongs to the Carmovirus genus of the Tombusviridae family, which includes carnation mottle virus (CarMV). The HCRSV virion has a 30 nm diameter icosahedral capsid with T = 3 quasi-symmetry containing 180 copies of a 38 kDa coat protein (CP) and encapsidates a full-length 3.9 kb genomic RNA. Authentic virus was harvested from infected host kenaf leaves and was purified by saturated ammonium sulfate precipitation, sucrose density-gradient centrifugation and anion-exchange chromatography. Virus crystals were grown in multiple conditions; one of the crystals diffracted to 3.2 A resolution and allowed the collection of a partial data set. The crystal belonged to space group R32, with unit-cell parameters a = b = 336.4, c = 798.5 A. Packing considerations and rotation-function analysis determined that there were three particles per unit cell, all of which have the same orientation and fixed positions, and resulted in tenfold noncrystallography symmetry for real-space averaging. The crystals used for the structure determination of southern bean mosaic virus (SBMV) have nearly identical characteristics. Together, these findings will greatly aid the high-resolution structure determination of HCRSV.


Assuntos
Carmovirus/química , Hibiscus/virologia , Sequência de Aminoácidos , Capsídeo/química , Capsídeo/ultraestrutura , Proteínas do Capsídeo/química , Proteínas do Capsídeo/ultraestrutura , Carmovirus/isolamento & purificação , Carmovirus/ultraestrutura , Cristalização , Coleta de Dados , Dimerização , Luz , Dados de Sequência Molecular , Peso Molecular , Tamanho da Partícula , Folhas de Planta/virologia , Dobramento de Proteína , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , RNA Viral/química , RNA Viral/ultraestrutura , Rotação , Espalhamento de Radiação , Homologia de Sequência de Aminoácidos , Estatística como Assunto , Temperatura , Vírion/química , Vírion/ultraestrutura , Difração de Raios X
13.
Cell Res ; 19(2): 187-95, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18813227

RESUMO

Influenza A viruses are important human pathogens causing periodic pandemic threats. Nonstructural protein 1 (NS1) protein of influenza A virus (NS1A) shields the virus against host defense. Here, we report the crystal structure of NS1A RNA-binding domain (RBD) bound to a double-stranded RNA (dsRNA) at 1.7A. NS1A RBD forms a homodimer to recognize the major groove of A-form dsRNA in a length-independent mode by its conserved concave surface formed by dimeric anti-parallel alpha-helices. dsRNA is anchored by a pair of invariable arginines (Arg38) from both monomers by extensive hydrogen bonds. In accordance with the structural observation, isothermal titration calorimetry assay shows that the unique Arg38-Arg38 pair and two Arg35-Arg46 pairs are crucial for dsRNA binding, and that Ser42 and Thr49 are also important for dsRNA binding. Agrobacterium co-infiltration assay further supports that the unique Arg38 pair plays important roles in dsRNA binding in vivo.Cell Research (2009) 19:187-195. doi: 10.1038/cr.2008.288; published online 23 September 2008.


Assuntos
Vírus da Influenza A/química , RNA de Cadeia Dupla/química , Proteínas não Estruturais Virais/química , Cristalografia por Raios X , Dimerização , Ligação de Hidrogênio , Vírus da Influenza A/genética , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , RNA de Cadeia Dupla/metabolismo , RNA Interferente Pequeno , Proteínas não Estruturais Virais/metabolismo
14.
Virology ; 335(2): 165-76, 2005 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-15840516

RESUMO

The RNA-dependent RNA polymerase (RdRp) of SARS coronavirus (SARS-CoV) is essential for viral replication and a potential target for anti-SARS drugs. We report here the cloning, expression, and purification of the N-terminal GST-fused SARS-CoV RdRp and its polymerase catalytic domain in Escherichia coli. During purification, the full-length GST-RdRp was found to cleave into three main fragments: an N-terminal p12 fragment, a middle p30 fragment, and a C-terminal p64 fragment comprising the catalytic domain, presumably due to bacterial proteases. Biochemical assays show that the full-length GST-RdRp has RdRp activity and the p64 and p12 fragments form a complex that exhibits comparable RdRp activity, whereas the GST-p64 protein has no activity, suggesting that the p12 domain is required for polymerase activity possibly via involvement in template-primer binding. Nonnucleoside HIV-1 RT inhibitors are shown to have no evident inhibitory effect on SARS-CoV RdRp activity. This work provides a basis for biochemical and structural studies of SARS-CoV RdRp and for development of anti-SARS drugs.


Assuntos
RNA Replicase/isolamento & purificação , RNA Replicase/metabolismo , Vírus da SARS/enzimologia , Fármacos Anti-HIV/farmacologia , Domínio Catalítico , Clonagem Molecular , Escherichia coli/genética , Expressão Gênica , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/isolamento & purificação , Fragmentos de Peptídeos/metabolismo , RNA Replicase/química , RNA Replicase/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Inibidores da Transcriptase Reversa/farmacologia , Síndrome Respiratória Aguda Grave/virologia
15.
Sheng Wu Gong Cheng Xue Bao ; 18(6): 693-7, 2002 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-12674639

RESUMO

A recombinant RGD-Staphylokinase(RGD-Sak) with thrombolytic and anti-thrombolytic bifunction was expressed in E. coli. The expression product accumulates as inclusion bodies. In order to obtain active molecule, the RGD-Sak in the inclusion body should be denatured and then renatured. The renaturation of RGD-Sak was performed by gel filtration. Comparing with the traditional way of dilution renaturation, gel filtration way is better than the traditional one, since there are some advantages, such as simple processing, high recovery, low cost and higher purity after renaturation, After renaturation, RGD-Sak was purified by Q-Sepharose FF, and the purity was more than 95%. Analysis of CD spectra showed that the final product from the two renaturation ways have similar CD spectra. It was demonstrated that RGD-Sak molecules proceeded correct refolding through gel filtration or dilution renaturation process.


Assuntos
Metaloendopeptidases/isolamento & purificação , Oligopeptídeos/isolamento & purificação , Proteínas Recombinantes de Fusão/isolamento & purificação , Cromatografia em Gel , Dicroísmo Circular , Metaloendopeptidases/química , Dobramento de Proteína , Renaturação Proteica , Proteínas Recombinantes de Fusão/química
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