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1.
J Am Chem Soc ; 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38838245

RESUMO

The activity of Ru-based alkaline hydrogen oxidation reaction (HOR) electrocatalysts usually decreases rapidly at potentials higher than 0.1 V (vs a reversible hydrogen electrode (RHE)), which significantly limits the lifetime of fuel cells. It is found that this phenomenon is caused by the overadsorption of the O species due to the overcharging of Ru nanoparticles at high potentials. Here, Mn1Ox(OH)y clusters-modified Ru nanoparticles (Mn1Ox(OH)y@Ru/C) were prepared to promote charge transfer from overcharged Ru nanoparticles to Mn1Ox(OH)y clusters. Mn1Ox(OH)y@Ru/C exhibits high HOR activity and stability over a wide potential range of 0-1.0 V. Moreover, a hydroxide exchange membrane fuel cell with a Mn1Ox(OH)y@Ru/C anode delivers a high peak power density of 1.731 W cm-2, much superior to that of a Pt/C anode. In situ X-ray absorption fine structure (XAFS) analysis and density functional theory (DFT) calculations reveal that Mn in Mn1Ox(OH)y clusters could receive more electrons from overcharged Ru at higher potentials and significantly decrease the overadsorption of the O species on Ru, thus permitting the HOR on Ru to proceed at high potentials. This study provides guidance for the design of alkaline HOR catalysts without activity decay at high potentials.

2.
Small ; 20(17): e2307780, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38168535

RESUMO

The development of high-performance, stable and platinum-free electrocatalysts for the hydrogen oxidation reaction (HOR) in alkaline media is crucial for the commercial application of anion exchange membrane fuel cells (AEMFCs). Ruthenium, as an emerging HOR electrocatalyst with a price advantage over platinum, still needs to solve the problems of low intrinsic activity and easy oxidation. Herein, Ru nanoparticles are anchored on the oxygen-vacancy-rich metalloid WO2.9 by interfacial engineering to create abundant and efficient Ru and WO2.9 interfacial active sites for accelerated HOR in alkaline media. Ru/WO2.9/C displays excellent catalytic activity with mass activity (8.29 A mgNM -1) and specific activity (1.32 mA cmNM -2), which are 2.5/3.3 and 21.8/8.3 times that of PtRu/C and Pt/C, respectively. Moreover, Ru/WO2.9/C exhibits excellent CO tolerance and operational stability. Experimental and theoretical studies reveal that the improved charge transfer from Ru to WO2.9 in the metal/metalloid heterostructure significantly tune the electronic structure of Ru sites and optimize the hydrogen binding energy (HBE) of Ru. While, WO2.9 provides abundant hydroxyl adsorption sites. Therefore, the equilibrium adsorption of hydrogen and hydroxyl at the interface of Ru/WO2.9 will be realized, and the oxidation of metal Ru would be avoided, thereby achieving excellent HOR activity and durability.

3.
Small ; : e2401404, 2024 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-38644200

RESUMO

Developing low-loading platinum-group-metal (PGM) catalysts is one of the key challenges in commercializing anion-exchange-membrane-fuel-cells (AEMFCs), especially for hydrogen oxidation reaction (HOR). Here, ruthenium-iridium nanoparticles being deposited on a Zn-N species-doped carbon carrier (Ru6Ir/Zn-N-C) are synthesized and used as an anodic catalyst for AEMFCs. Ru6Ir/Zn-N-C shows extremely high mass activity (5.87 A mgPGM -1) and exchange current density (0.92 mA cm-2), which is 15.1 and 3.9 times that of commercial Pt/C, respectively. Based on the Ru6Ir/Zn-N-C AEMFCs achieve a peak power density of 1.50 W cm-2, surpassing the state-of-the-art commercial PtRu catalysts and the power ratio of the normalized loading is 14.01 W mgPGM anode -1 or 5.89 W mgPGM -1 after decreasing the anode loading (87.49 µg cm-2) or the total PGM loading (0.111 mg cm-2), satisfying the US Department of Energy's PGM loading target. Moreover, the solvent and solute isotope separation method is used for the first time to reveal the kinetic process of HOR, which shows the reaction is influenced by the adsorption of H2O and OH-. The improvement of the hydrogen bond network connectivity of the electric double layer by adjusting the interfacial H2O structure together with the optimized HBE and OHBE is proposed to be responsible for the high HOR activity of Ru6Ir/Zn-N-C.

4.
J Am Chem Soc ; 145(50): 27867-27876, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38079607

RESUMO

Efficient and CO-tolerant catalysts for alkaline hydrogen oxidation (HOR) are vital to the commercial application of anion exchange membrane fuel cells (AEMFCs). Herein, a robust Ru-based catalyst (Ru/VOC) with ultrasmall Ru nanoparticles supported on carbon frameworks with atomically dispersed V-O species is prepared elaborately. The catalyst exhibits a remarkable mass activity of 3.44 mA µgPGM, which is 31.3 times that of Ru/C and even 4.7 times higher than that of Pt/C. Moreover, the Ru/VOC anode can achieve a peak power density (PPD) of 1.194 W cm-2, much superior to that of Ru/C anode and even better than that of Pt/C anode. In addition, the catalyst also exhibits superior stability and exceptional CO tolerance. Experimental results and density functional theory (DFT) calculations demonstrate that V-O species are ideal OH- adsorption sites, which allow Ru to release more sites for hydrogen adsorption. Furthermore, the electron transfer from Ru nanoparticles to the carbon substrate regulates the electronic structure of Ru, reducing the hydrogen binding energy (HBE) and the CO adsorption energy on Ru, thus boosting the alkaline HOR performance and CO tolerance of the catalyst. This is the first report that oxophilic single atoms distributed on carbon frameworks serve as OH- adsorption sites for efficient hydrogen oxidation, opening up new guidance for the elaborate design of high-activity catalysts for the alkaline HOR.

5.
Angew Chem Int Ed Engl ; 57(15): 3949-3953, 2018 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-29437274

RESUMO

Membrane voltage is an important biophysical signal that underlies intercellular electrical communications. A fluorescent voltage indicator is presented that enables the investigation of electrical signaling at high spatial resolution. The method is built upon the site-specific modification of microbial rhodopsin proteins with organic fluorophores, resulting in a hybrid indicator scaffold that is one of the most sensitive and fastest orange-colored voltage indicators developed to date. We applied this technique to optically map electrical connectivity in cultured cells, which revealed gap junction-mediated long-range coupling that spanned over hundreds of micrometers.


Assuntos
Corantes Fluorescentes/química , Rodopsina/química , Acetabularia/metabolismo , Potenciais de Ação/fisiologia , Química Click , Condutividade Elétrica , Transferência Ressonante de Energia de Fluorescência , Junções Comunicantes/metabolismo , Células HEK293 , Humanos , Microscopia Confocal , Peptídeos/química
6.
PLoS Genet ; 8(7): e1002791, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22807686

RESUMO

Genome-wide association studies (GWAS) have recently identified KIF1B as susceptibility locus for hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC). To further identify novel susceptibility loci associated with HBV-related HCC and replicate the previously reported association, we performed a large three-stage GWAS in the Han Chinese population. 523,663 autosomal SNPs in 1,538 HBV-positive HCC patients and 1,465 chronic HBV carriers were genotyped for the discovery stage. Top candidate SNPs were genotyped in the initial validation samples of 2,112 HBV-positive HCC cases and 2,208 HBV carriers and then in the second validation samples of 1,021 cases and 1,491 HBV carriers. We discovered two novel associations at rs9272105 (HLA-DQA1/DRB1) on 6p21.32 (OR = 1.30, P = 1.13×10⁻¹9) and rs455804 (GRIK1) on 21q21.3 (OR = 0.84, P = 1.86×10⁻8), which were further replicated in the fourth independent sample of 1,298 cases and 1,026 controls (rs9272105: OR = 1.25, P = 1.71×10⁻4; rs455804: OR = 0.84, P = 6.92×10⁻³). We also revealed the associations of HLA-DRB1*0405 and 0901*0602, which could partially account for the association at rs9272105. The association at rs455804 implicates GRIK1 as a novel susceptibility gene for HBV-related HCC, suggesting the involvement of glutamate signaling in the development of HBV-related HCC.


Assuntos
Carcinoma Hepatocelular/genética , Cadeias alfa de HLA-DQ/genética , Neoplasias Hepáticas/genética , Receptores de Ácido Caínico/genética , Adulto , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/virologia , Feminino , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Vírus da Hepatite B/genética , Humanos , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/virologia , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único
8.
Transl Neurosci ; 15(1): 20220337, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38584670

RESUMO

Background: Forkhead box P3 (FOXP3) plays a critical role in the pathogenesis of autoimmune disorders. In the present study, we genotyped three single-nucleotide polymorphisms, namely, rs2232365, rs3761548, and rs3761549, to determine the relationship between FOXP3 polymorphisms and neuromyelitis optica spectrum disorder (NMOSD) susceptibility among the Northern Chinese Han population. Materials and methods: We genotyped single nucleotide polymorphisms at loci of the FOXP3 gene (rs2232365, rs3761548, and rs3761549136) in 136 NMOSD patients and 224 healthy subjects using the multiplex SNaPshot technique. Allele, genotype, and haplotype frequencies were compared. qPCR was used to analyze the mRNA expression levels of FOXP3 in the peripheral blood mononuclear cells of 63 NMOSD patients and 35 healthy subjects. Non-parametric tests were used to test the FOXP3 mRNA expression across the different groups. Results: The minor allele frequency (MAF) of G in rs2232365 was markedly lower in the NMOSD group than in the control group (odds ratio [OR] = 0.57, 95% confidence interval [95% CI]: 0.41-0.79, p = 0.001). Using genetic (codominant, dominant, and recessive) models and performing haplotype analyses, the MAF of G in rs2232365 was shown to be associated with protection against NMOSD in this population. Furthermore, haplotype analysis revealed that the haplotype GCT and the rs2232365, rs3761548, and rs3761549 alleles predicted protection against NMOSD (OR = 0.63, 95% CI = 0.41-0.97, p = 0.038). The proportions of the three genotypes of rs2232365 (p = 0.001) were not significantly different between the moderate-to-severe (Expanded Disability Status Scale (EDSS) ≥ 3 points) and mild (EDSS < 3 points) groups. Evidently, the proportion of patients with the AA genotype (64.3%) among the rs2232365 patients was significantly greater in the moderate-to-severe group than in the mild group (36.4%). However, the proportion of patients with the GG genotype (15.2%) among the rs2232365 patients was significantly greater in the mild group than in the moderate-to-severe group (2.9%). The mRNA expression of FOXP3 was markedly greater in the NMOSD group than in the control group (p = 0.001). Nevertheless, acute non-treatment patients exhibited lower FOXP3 mRNA expression than healthy controls and patients in the remission group (p = 0.004 and 0.007, respectively). Conclusion: FOXP3 polymorphisms and haplotypes are related to NMOSD susceptibility among the Han Chinese population. The minor allele G of FOXP3 rs2232365 and the haplotype GCT are associated with protection against NMOSD. The GG genotype may decrease the severity of NMOSD, whereas the AA genotype is related to moderate-to-severe NMOSD. FOXP3 mRNA expression is greater in patients with NMOSD than in healthy controls. However, it is decreased in acute non-treatment patients compared with healthy controls.

9.
J Hepatol ; 59(3): 518-27, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23665284

RESUMO

BACKGROUND & AIMS: The dysfunction of miRNAs has been demonstrated to participate in the development of various tumors. However, whether miRNAs are involved in metastasis and progression of gallbladder carcinoma (GBC) remains unknown. METHODS: A new designed gain-of-function miRNA screening technology was applied to filter out pro-metastatic miRNAs in GBC. Their expression in GBC tissues was validated by real-time PCR. The biological functions of miRNAs were intensively studied by transwell, immunoblot, immunohistochemical, and in situ hybridization assays. Tumorigenicity and liver metastasis were further examined in nude mice. RESULTS: Of 880 miRNAs, 17 were filtered out as the prominent metastatic inducers of GBCs. Among them, the upregulation of pro-metastatic miR-20a was closely associated with local invasion, distant metastasis, and poor prognosis of 67 followed-up GBC patients, clinically. Patients with higher miR-20a expression exhibited worse overall survival (OS and median OS time was 5 and 20 months, respectively) than the lower expression group. A dramatically increased TGF-ß1 level was found in GBC patients, which was responsible for the elevation of miR-20a. The ectopic expression of miR-20a could induce epithelial-mesenchymal transition and enhance metastasis of GBC cells in vitro and in vivo, by directly targeting the 3' UTR of Smad7, and subsequently promoting nuclear translocation of ß-catenin. Conversely, the blockage of miR-20a by specific antagomir effectively restored the expression of Smad7 and attenuated TGF-ß-induced cell metastasis. CONCLUSIONS: TGF-ß1-mediated activation of the miR-20a/Smad7/ß-catenin axis plays a pivotal role in the pathogenesis and worse prognosis of GBCs and may serve as a potential therapeutic target in the future.


Assuntos
Neoplasias da Vesícula Biliar/genética , Neoplasias da Vesícula Biliar/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Metástase Neoplásica/genética , Animais , Linhagem Celular Tumoral , Progressão da Doença , Transição Epitelial-Mesenquimal/genética , Feminino , Neoplasias da Vesícula Biliar/patologia , Xenoenxertos , Humanos , Neoplasias Hepáticas Experimentais/genética , Neoplasias Hepáticas Experimentais/metabolismo , Neoplasias Hepáticas Experimentais/secundário , Masculino , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Invasividade Neoplásica , Transplante de Neoplasias , Prognóstico , RNA Neoplásico/genética , RNA Neoplásico/metabolismo , Proteína Smad7/genética , Proteína Smad7/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , beta Catenina/genética , beta Catenina/metabolismo
10.
Hepatol Res ; 43(1): 72-83, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22971038

RESUMO

AIM: There is no clear consensus on the optimal timing of surgical resection for synchronous colorectal liver metastases (SCLM). This study is a meta-analysis of the available evidence. METHODS: Systematic review and meta-analysis of trials comparing outcomes following simultaneous resection with staged resection for SCLM published from 1990 to 2010 in PubMed, Embase, Ovid and Medline. Pooled odds ratios (OR) or weighted mean differences (WMD) with 95% confidence intervals (95% CI) were calculated using either the fixed effects or random effects model. RESULTS: Nineteen non-randomized controlled trials (NRCT) studies were included in this analysis. These studies included a total of 2724 patients: 1116 underwent simultaneous resection and 1608 underwent staged resection. Meta-analysis showed that shorter hospital stay (P < 0.001) and lower total complication rate (P < 0.001) were observed in patients undergoing simultaneous resection group. The overall survival rate in the simultaneous resection group did not statistically differ with that in the staged resection group at 1 year (P = 0.13), 3 years (P = 0.26), 5 years (P = 0.38), as well as the 1, 3 and 5 years disease-free survival rates (respectively, P = 0.55; P = 0.16; P = 0.12). No significant difference was noted between the two groups in terms of mortality (P = 0.16), intraoperative blood loss (P = 0.06) and recurrence (P = 0.47). CONCLUSION: Simultaneous resection is safe and efficient in the treatment of patients with SCLM while avoiding a second laparotomy. In selected patients, simultaneous resection might be considered as the preferred approach. However, the findings have to be carefully interpreted due to the lower level of evidence and the existence of heterogeneity.

11.
Hepatol Res ; 43(5): 516-25, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-22900980

RESUMO

AIM: The human sulfatase-1 (hSulf-1) gene regulates the sulfation of heparan sulfate proteoglycans (HSPG) and suppresses tumorigenesis and angiogenesis by inhibiting several growth factor signaling pathways. Because the serine-threonine protein kinase (AKT) and extracellular signal-regulated kinase (ERK) signaling pathways are critical in cell survival, proliferation, migration and angiogenesis, the possible correlation between hSulf-1 and AKT/ERK signaling in hepatocellular carcinoma (HCC) cells needs further exploration. METHODS: Adenovirus Ad5-hSulf1 carrying the hSulf-1 gene, and vectors carrying hSulf-1 shRNA, AKT shRNA and ERK shRNA were constructed and used to manipulate the expression of hSulf-1, AKT and ERK in SMMC-7721 cells. The scarification test, transwell and 3-(4 5-dimethylthiazol-2-yl)-2 5-diphenyltetrazolium bromide assays were used to examine the cellular migration and proliferation, and the expression of hSulf-1 and signaling factors, including the total and phosphorylated AKT and ERK, was analyzed by western blot in SMMC-7721 cells. RESULTS: After infection with Ad5-hSulf1, the expression of hSulf-1 was increased with viral multiplicity of infection in SMMC-7721 cells. Compared with the control adenovirus Ad5-EGFP and blank control groups, cells in the Ad5-hSulf1 group were showed that the phosphorylation of AKT and ERK was decreased. Meanwhile, the cell migration and cell viability were obviously suppressed. CONCLUSION: The expression of hSulf-1 mediated by adenovirus in HCC cells could downregulate the activity of AKT and ERK signaling pathways, and inhibit HCC cell migration and proliferation. The hSulf-1 gene may be considered as a candidate of antitumor factor for cancer gene therapy.

12.
Diagnostics (Basel) ; 13(5)2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36899959

RESUMO

Chordoid meningioma (CM) makes up only 1% of all meningiomas. Most cases of this variant are locally aggressive, have high growth potential, and are likely to recur. Although CMs are known to be invasive, they rarely extend into the retro-orbital space. Herein, we report a case of a central skull base CM in a 78-year-old woman whose only manifestation was unilateral proptosis with impaired vision resulting from the tumor extending into the retro-orbital space through the superior orbital fissure. The diagnosis was confirmed by analysis of specimens collected during endoscopic orbital surgery, which simultaneously relieved the protruding eye and restored the patient's visual acuity by decompressing the oppressed orbit. This rare presentation of CM reminds physicians there may be lesions outside the orbit that can cause unilateral orbitopathy and that endoscopic orbital surgery can be used to confirm its diagnosis as well as treat it.

13.
Biochim Biophys Acta Mol Cell Res ; 1870(8): 119568, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37597773

RESUMO

Hydrogen sulfide (H2S) is the third gas signaling molecule that has been shown to be involved in the regulating vital activities in the body, including inhibition of aging. However, it is unknown whether H2S alleviates aging in the kidney and glomerular mesangial cells (GMCs) by modulating their mitophagy. Here, results of experiments in vivo and in vitro showed that compared with control group, the renal function of mice and GMCs viability were decreased in D-gal (D-galactose) group, while the activity of SA-ß-gal and p21 expression were increased, Cyclin D1 and Klotho expressions were decreased; H2S content and CSE expression were lower; ROS and MDA contents and mitochondrial permeability transition pore (mPTP) opening were risedose; ATP production and mitochondrial membrane potential (Δψm) were reduced; Apoptotic rate, the expression of Cleaved caspase-9 and -3, Cyt c, p62 and Drp1 were enhanced and the expression of Bcl-2, Mfn2, Beclin-1, LC3 II/I, PINK1 and parkin were decreased. In addition, phospho-AMPK/AMPK and phospho-ULK1/ULK1 were also decreased significantly. Compared with the D-gal group, the changes of above indexes were reversed in the D-gal + NaHS (Sodium hydrosulfide, an exogenous H2S donor) group. The reverse effects of NaHS were similar to that of AICAR (an AMPK agonist) and kinetin (a PINK1 agonist), respectively. Taken together, these results suggest that exogenous H2S increases mitophagy and inhibits apoptosis as well as oxidative stress through up-regulation of AMPK-ULK1-PINK1-parkin pathway, which delays kidney senescence in mice.


Assuntos
Células Mesangiais , Mitofagia , Proteínas Quinases Ativadas por AMP , Rim , Estresse Oxidativo
14.
Tumour Biol ; 33(6): 2041-51, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22890827

RESUMO

A great number of studies regarding the association between MTHFR C677T polymorphism and risk of colorectal cancer (CRC) in East Asians were published, but the results were inconsistent. Thus, a meta-analysis was performed to investigate the association. PubMed, Embase, and CBM databases were searched for eligible publications. Pooled odds ratios (ORs) with 95 % confidence intervals (95 % CIs) were calculated using random or fixed effect models. Finally, 24 case-control studies with a total of 7,230 CRC cases and 9,285 controls were included. Meta-analyses of a total of 24 studies showed there was a statistically significant association between MTHFR C677T polymorphism and decreased CRC risk in East Asians under four genetic models (T versus C, OR = 0.92, 95 % CI 0.85-0.99; TT versus CC, OR = 0.80, 95 % CI 0.69-0.94; TT versus CT/CC, OR = 0.82, 95 % CI 0.71-0.95; TT/CT versus CC, OR = 0.92, 95 % CI 0.86-0.98). The cumulative meta-analyses for the allele contrast (T versus C), homozygote (TT versus CC), dominant (TT/CT versus CC), and recessive (TT versus CT/CC) models all showed a trend of more obvious association as information accumulated by year. Subgroup analyses by country further identified this association in Korea and Japan. This meta-analysis suggests that MTHFR C677T polymorphism is associated with decreased risk of colorectal cancer in East Asians, and MTHFR 677T variant has a protective effect on colorectal cancer.


Assuntos
Povo Asiático/genética , Neoplasias Colorretais/etiologia , Predisposição Genética para Doença , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Polimorfismo de Nucleotídeo Único/genética , Neoplasias Colorretais/epidemiologia , Ásia Oriental/epidemiologia , Humanos , Prognóstico , Fatores de Risco
15.
J Gastroenterol Hepatol ; 27(2): 231-7, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21916987

RESUMO

BACKGROUND AND AIM: Previous studies investigating the association between the glutathione S-transferase Tl (GSTT1) null genotype and colorectal cancer (CRC) risk in the Asian population have reported controversial results. Thus, a meta-analysis was performed to clarify the effect of the GSTT1 null genotype on CRC risk in the Asian population. METHODS: A comprehensive study was conducted, and 12 case-control studies were finally included, involving a total of 4517 CRC cases and 6607 controls. Subgroup analyses were performed by the sample size. RESULTS: A meta-analysis of all 12 studies showed that the GSTT1 null genotype was significantly associated with an increased CRC risk in the Asian population (odds ratio [OR] = 1.10, 95% confidence interval [CI] = 1.02-1.19, the P-value of the OR [P(OR)] = 0.02, the value of the heterogeneity analysis [I(2)] = 42%). A more obvious association was observed after the heterogeneity was eliminated by excluding one study (OR = 1.15, 95% CI: 1.06-1.25, P(OR) = 0.001, I(2) = 0%). This association was further identified by both subgroup analyses and a sensitivity analysis. CONCLUSIONS: This meta-analysis suggests that the GSTT1 null genotype contributes to an increased colorectal cancer risk in the Asian population.


Assuntos
Povo Asiático/genética , Neoplasias Colorretais/genética , Glutationa Transferase/genética , Ásia/epidemiologia , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Neoplasias Colorretais/enzimologia , Neoplasias Colorretais/etnologia , Feminino , Frequência do Gene , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Fenótipo , Medição de Risco , Fatores de Risco
16.
Commun Biol ; 5(1): 735, 2022 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-35869167

RESUMO

Mast cell products and high levels of type 2 cytokines are associated with severe dengue disease. Group 2 innate lymphoid cells (ILC2) are type-2 cytokine-producing cells that are activated by epithelial cytokines and mast cell-derived lipid mediators. Through ex vivo RNAseq analysis, we observed that ILC2 are activated during acute dengue viral infection, and show an impaired type I-IFN signature in severe disease. We observed that circulating ILC2 are permissive for dengue virus infection in vivo and in vitro, particularly when activated through prostaglandin D2 (PGD2). ILC2 underwent productive dengue virus infection, which was inhibited through CRTH2 antagonism. Furthermore, exogenous IFN-ß induced expression of type I-IFN responsive anti-viral genes by ILC2. PGD2 downregulated type I-IFN responsive gene and protein expression; and urinary prostaglandin D2 metabolite levels were elevated in severe dengue. Moreover, supernatants from activated ILC2 enhanced monocyte infection in a GM-CSF and mannan-dependent manner. Our results indicate that dengue virus co-opts an innate type 2 environment to escape early type I-IFN control and facilitate viral dissemination. PGD2 downregulates type I-IFN induced anti-viral responses in ILC2. CRTH2 antagonism may be a therapeutic strategy for dengue-associated disease.


Assuntos
Vírus da Dengue , Dengue Grave , Citocinas/metabolismo , Vírus da Dengue/metabolismo , Humanos , Imunidade Inata , Linfócitos/metabolismo , Prostaglandinas/metabolismo , Dengue Grave/metabolismo , Replicação Viral
17.
Aging (Albany NY) ; 13(4): 5585-5606, 2021 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-33591950

RESUMO

Transmembrane protein (TMEM) is a kind of integral membrane protein that spans biological membranes. The functions of most members of the TMEM family are unknown. Here, we conducted bioinformatic analysis and biological validation to investigate the role of TMEM106C in HCC. First, GEPIA and OncomineTM were used to analyze TMEM106C expression, which was verified by real-time PCR and western blot analyses. Then, the biological functions of TMEM106C were explored by CCK8 and transwell assays. The prognostic value of TMEM106C was analyzed by UALCAN. LinkedOmics was used to analyze TMEM106C pathways generated by Gene Ontology. A protein-protein interaction network (PPI) was constructed by GeneMANIA. We demonstrated that TMEM106C was overexpressed in HCC and that inhibition of TMEM106C significantly suppressed the proliferation and metastasis of HCC through targeting CENPM and DLC-1. Upregulation of TMEM106C was closely correlated with sex, tumor stage, tumor grade and prognosis. Overexpression of TMEM106C was linked to functional networks involving organelle fission and cell cycle signaling pathways through the regulation of CDK kinases, E2F1 transcription factors and miRNAs. Our data demonstrated that TMEM106C contributes to malignant characteristics and poor prognosis in HCC, which may serve as a prognostic biomarker and potential therapeutic target.


Assuntos
Carcinoma Hepatocelular/metabolismo , Proteínas de Ciclo Celular/metabolismo , Proteínas Ativadoras de GTPase/metabolismo , Neoplasias Hepáticas/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/mortalidade , Estudos de Casos e Controles , China/epidemiologia , Feminino , Células Hep G2 , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/mortalidade , Masculino , Prognóstico
18.
Front Mol Biosci ; 8: 743013, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34616773

RESUMO

Background: Exosomes, as natural intercellular information carriers, have great potential in the field of drug delivery. Many studies have focused on modifying exosome surface proteins to allow drugs to specifically target cancer cells. Methods: In this study, human cord blood mesenchymal stromal cell-derived exosomes were used in the delivery of anti-miRNA oligonucleotides so as to be specifically ingested by tumor cells to perform anti-tumor functions. Mesenchymal stem cells modified by the fusion gene iRGD-Lamp2b were constructed to separate and purify exosomes, and the anti-miRNA-221 oligonucleotide (AMO) was loaded into the exosomes by electroporation. Results: The AMO-loaded exosomes (AMO-Exos) effectively inhibited the proliferation and clonal formation of colon cancer cells in vitro, and it was further found that AMO-Exos was taken up by tumor cells through interaction with the NRP-1 protein. The results of a xenograft tumor model also showed that iRGD-modified exosomes were obviously enriched in tumor sites, exerting excellent anti-tumor efficacy. In vivo imaging showed that exosomes were mainly distributed in liver, spleen, and lung tissues. Conclusion: Our results suggest that genetically modified exosomes could be an ideal natural nanostructure for anti-miRNA oligonucleotide delivery.

19.
Mol Ther Nucleic Acids ; 26: 1215-1227, 2021 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-34853721

RESUMO

Dysregulated alternative splicing (AS) plays critical roles in driving cancer progression, and the underlying mechanisms remain largely unknown. Here, we demonstrated that PHF5A, a component of U2 small nuclear ribonucleoproteins, was frequently upregulated in colorectal cancer (CRC) samples and associated with poor prognosis. PHF5A promoted proliferation and metastasis of CRC cells in vitro and in vivo. Transcriptomic analysis identified PHF5A-regulated AS targets and pathways. Particularly, PHF5A induced TEAD2 exon 2 inclusion to activate YAP signaling, and interference of TEAD2-L partially reversed the PHF5A-mediated tumor progression. Pharmacological inhibition of PHF5A using pladienolide B had potent antitumor activity. Collectively, these data revealed the oncogenic role of PHF5A in CRC through regulating AS and established PHF5A as potential therapeutic target.

20.
J Gastroenterol ; 55(1): 51-66, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31562534

RESUMO

BACKGROUND: Gallbladder carcinoma (GBC) is one of the most aggressive and lethal tumors, with extremely high metastatic activity and poor prognosis. Previously we have studied miRNAs that promote metastasis and progression of GBC, the aim of present study was to systematically elucidate the metastasis suppressor miRNAs in GBC. METHODS: A novel designed high-throughput screening method that combined high content screening (HCS) and miRNA microarray analysis was conducted to filter out anti-metastatic miRNAs of GBC. Frozen samples were analyzed for the expression of goal miRNAs by real-time PCR. The biological functions of miRNAs were studied by transwell, immunoblot. Liver metastasis model via spleen injection was further examined in nude mice. Kaplan-Meier and Cox regression analyses were used to analyze the effect of goal miRNAs on overall survival. The target genes and interaction network of goal miRNAs were determined by whole transcriptome genome sequencing. RESULTS: Out of the miRNAs library, a series of prominent metastatic suppressor miRNA candidates were filtered out. Among them, miR-7-2-3p and miR-29c-3p were discovered downregulated in GBC, and upregulation of them could reverse epithelial-mesenchymal transition and decrease the metastasis ability of GBC cells in vitro and in vivo, which was dominated by the miRNA-mRNA-lncRNA co-expression network. And DCLK1 and SLC36A1 are the direct target genes of miR-7-2-3p and miR-29c-3p. Moreover, the deficiency of miR-7-2-3p and miR-29c-3p was closely associated with poor prognosis of GBC patients. CONCLUSIONS: Our findings indicate that miR-7-2-3p and miR-29c-3p play crucial roles in the pathogenesis and worse prognosis of GBCs, which may serve as prognosis biomarkers and promise potential therapeutic targets in the future.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias da Vesícula Biliar/genética , Neoplasias da Vesícula Biliar/patologia , MicroRNAs/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Biomarcadores Tumorais/genética , Western Blotting , Linhagem Celular Tumoral , Regulação para Baixo , Feminino , Seguimentos , Neoplasias da Vesícula Biliar/diagnóstico , Neoplasias da Vesícula Biliar/mortalidade , Ensaios de Triagem em Larga Escala , Humanos , Immunoblotting , Masculino , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Metástase Neoplásica , Análise de Sequência com Séries de Oligonucleotídeos , Prognóstico , Reação em Cadeia da Polimerase em Tempo Real , Estudos Retrospectivos , Análise de Sobrevida , Regulação para Cima , Sequenciamento do Exoma
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