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1.
ACS Appl Mater Interfaces ; 13(36): 42861-42869, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34473469

RESUMO

Ni(OH)2-based materials are widely studied in oxygen evolution reaction (OER), but no related synthesis, electrocatalytic application, or theoretical analysis of Sn4+-doped Ni(OH)2 has been reported. In this work, Sn-Ni(OH)2 with a homogeneously distributed nanosheet array was synthesized through a one-step hydrothermal process. It displays a hugely enhanced catalytic activity compared to undoped Ni(OH)2 throughout the OER and hydrogen evolution reaction (HER) processes. The overpotentials at 100 mA cm-2 of Sn-Ni(OH)2 are 312 mV (OER) and 298 mV (HER), which are lower than the corresponding 396 and 427 mV of Ni(OH)2, respectively. In addition, Sn-Ni(OH)2 can deliver stable large current densities (at ≈500 and ≈1000 mA cm-2) for the long-term (>100 h) chronoamperometry testing. Moreover, Sn-Ni(OH)2 illustrates catalytic activity comparable to that of a commercial Pt/C||RuO2 electrode pair during the overall water splitting course. Both experimental phenomena and relevant computed theoretical data confirm that the enhanced water splitting activity is mainly due to the introduced Sn4+ site, which acts as the active center activates the nearby Ni sites during the OER, while acting as the most active reaction site that participates in the HER. Although the doped Sn4+ has two different effects on OER and HER proceedings, water splitting performance of Sn-Ni(OH)2 has been conspicuously improved.

2.
Mol Ther Nucleic Acids ; 26: 49-62, 2021 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-34513293

RESUMO

As a robust antagonist of myostatin (MSTN), follistatin (FST) is an important regulator of skeletal muscle development, and the delivery of FST to muscle tissue represents a potential therapeutic strategy for muscular dystrophies. The N terminus and FSI domain of FST are the functional domains for MSTN binding. Here, we aimed to achieve site-specific integration of FSI-I-I, including the signal peptide, N terminus, and three FSI domains, into the last codon of the porcine MSTN gene using a homology-mediated end joining (HMEJ)-based strategy mediated by CRISPR-Cas9. Based on somatic cell nuclear transfer (SCNT) technology, we successfully obtained FSI-I-I knockin pigs. H&E staining of longissimus dorsi and gastrocnemius cross-sections showed larger myofiber sizes in FSI-I-I knockin pigs than in controls. Moreover, the Smad and Erk pathways were inhibited, whereas the PI3k/Akt pathway was activated in FSI-I-I knockin pigs. In addition, the levels of MyoD, Myf5, and MyoG transcription were upregulated while that of MRF4 was downregulated in FSI-I-I knockin pigs. These results indicate that the FSI-I-I gene mediates skeletal muscle hypertrophy through an MSTN-related signaling pathway and the expression of myogenic regulatory factors. Overall, FSI-I-I knockin pigs with hypertrophic muscle tissue hold great promise as a therapeutic model for human muscular dystrophies.

3.
Sci Total Environ ; 771: 144883, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33736155

RESUMO

Understanding pollen transport pathways and dispersal mechanism from the land to sea is a prerequisite for marine palynological study. Palynological analysis of 164 surface sediment samples in Liaodong Bay, and 39 analogous surface alluvium samples from its five inflowing rivers, identifies the distribution patterns, pathways and possible sources of pollen and spores. The results show that pollen and spore assemblages in surface sediments are well correlated to regional vegetation distribution, and the variations of pollen assemblage in different parts of Liaodong Bay reflected local vegetation changes along the coast. High pollen concentrations are mainly distributed in the estuaries of inflowing rivers, coastal waters and sea muddy areas. The pollen assemblage characteristics of alluvial samples are similar to those from coastal waters with water depths <8.5 m. Samples from the alluvium and surface sediments of coastal waters were dominated by herbaceous pollen taxa including Artemisia, Amaranthaceae, Poaceae, Cyperaceae and Typha. Herbaceous pollen percentages and concentrations decreased as the water depth increased, indicating that pollen and spores in the coastal waters of Liaodong Bay are mainly carried by the inflowing rivers. However, pollen assemblages for samples with water depth >8.5 m are significantly different from those of the alluvium. In samples taken below a depth of 8.5 m, the arboreal pollen is dominated by airborne Pinus, and there is a high number of the waterborne Selaginella fern spores, both of which are sourced from a wider region. In the Liaodong Bay, both wind and ocean current transportation determines the pollen distribution patterns in deeper waters, while fluvial and longshore current transportation determines the pollen assemblages found in shallow waters. The dispersal characteristics of pollen assemblages between the land and the sea in Liaodong Bay provide a theoretical basis for the interpretation of fossil pollen assemblages and past sea level changes.


Assuntos
Baías , Poluentes Químicos da Água , China , Monitoramento Ambiental , Estuários , Sedimentos Geológicos , Pólen/química , Rios , Poluentes Químicos da Água/análise
4.
Dalton Trans ; 50(9): 3240-3246, 2021 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-33585853

RESUMO

A new three-dimensional (3-D) inorganic metal-oxygen network vanadoborate Na3H10[Ni(H2O)2(VO)6(B10O22)2]·NH4·19H2O (1) constructed from lantern-type {(VO)6(B10O22)2} clusters, NaO6 polyhedra and NiO6 octahedra, was successfully synthesized by a hydrothermal method. In the structure, the {V6B20} clusters are linked together through NiO6 octahedral bridges, resulting in 1-D chains along the c-axis. The 1-D chains are further connected by NaO6 polyhedra to give rise to a 3-D open-framework structure. Furthermore, lots of NH4+ and H2O molecules are accommodated in the void of the structure, and may interact with the [V6B20] system via N-HO, O-HO hydrogen bonds, constructing a complex hydrogen-bonding network system. Strikingly, compound 1 exhibited a high proton conductivity of 3.22 × 10-3 S cm-1 at 50 °C under 100% RH with an activation energy of 1.66 eV.

5.
Haematologica ; 106(3): 829-837, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31974191

RESUMO

Hemophilia B is an X-linked recessive bleeding disorder caused by abnormalities in the coagulation factor IX gene. Without prophylactic treatment, patients experience frequent spontaneous bleeding episodes. Well-characterized animal models are valuable for determining the pathobiology of the disease and testing novel therapeutic innovations. Here, we generated a porcine model of hemophilia B using a combination of CRISPR/Cas9 and somatic cell nuclear transfer. Moreover, we tested the possibility of hemophilia B therapy by gene insertion. Frequent spontaneous joint bleeding episodes that occurred in hemophilia B pigs allowed a thorough investigation of the pathological process of hemophilic arthropathy. In contrast to the hemophilia B pigs, which showed a severe bleeding tendency and joint damage, the transgenic pigs carrying human coagulation factor IX exhibited a partial improvement of bleeding. In summary, this study not only offers a translational hemophilia B model for exploring the pathological process of hemophilic arthropathy but also provides a possibility for the permanent correction of hemophilia in the future by genome editing in situ.


Assuntos
Hemofilia A , Hemofilia B , Animais , Sistemas CRISPR-Cas , Fator IX/genética , Hemofilia A/genética , Hemofilia B/genética , Hemofilia B/terapia , Hemorragia/genética , Humanos , Suínos
6.
Bone ; 137: 115450, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32450343

RESUMO

Loss-of-function mutations in the COL2A1 gene were previously described as a cause of type II collagenopathy (e.g., spondyloepiphyseal dysplasia, Stickler syndrome type I), a major subgroup of genetic skeletal diseases. However, the pathogenic mechanisms associated with COL2A1 mutations remain unclear, and there are few large-mammal models of these diseases. In this study, we established a swine model carrying COL2A1 mutations using CRISPR/Cas9 and somatic cell nuclear transfer technologies. Animals mutant for COL2A1 exhibited severe skeletal dysplasia characterized by shortened long bones, abnormal vertebrae, depressed nasal bridge, and cleft palate. Importantly, COL2A1 mutant piglets suffered tracheal collapse, which was almost certainly the cause of their death shortly after birth. In conclusion, we have demonstrated for the first time that overt and striking skeletal dysplasia occurring in human patients can be recapitulated in large transgenic mammals. This model underscores the importance of employing large animals as models to investigate the pathogenesis and potential therapeutics of skeletal diseases.


Assuntos
Doenças do Tecido Conjuntivo , Perda Auditiva Neurossensorial , Osteocondrodisplasias , Animais , Animais Geneticamente Modificados , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Colágeno Tipo II/genética , Doenças do Tecido Conjuntivo/genética , Modelos Animais de Doenças , Perda Auditiva Neurossensorial/genética , Humanos , Mutação/genética , Osteocondrodisplasias/genética , Suínos
7.
J Am Chem Soc ; 142(7): 3316-3320, 2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-32003216

RESUMO

The combination of ferroelectric-optical properties in halide perovskites has attracted tremendous interess because of its potential for optoelectronic and energy applications. However, very few reports focus on the ferroelectricity of all-inorganic halide perovskites quantum dots. Herein, we report a excellent ferroelectricity in CsPbBr3 quantum dots (QDs) with a saturation polarization of 0.25 µC/cm2. Differential scanning calorimetry, X-ray diffraction, and transmission electronic microscopy revealed that the mechanism of ferroelectric-paraelectric switching of CsPbBr3 QDs can be attributed to the phase transition from cubic phase (Pm3̅m) to the orthorhombic phase (Pna21). In the orthorhombic CsPbBr3, the distortion of octahedral [PbBr6]4- structural units and the off-center Cs+ generated the slightly separated centers of positive charge and negative charge, resulting in the ferroelectric properties. The variable-temperature emission spectrum from 328 to 78 K exhibits green luminescence and a gradual red shift due to the phase transition. This finding opens up an avenue to explore the ferroelectric-optical properties of inorganolead halide perovskites for high-performance multifunctional materials.

8.
Biosens Bioelectron ; 153: 112045, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31989940

RESUMO

Ionic liquid composite electrodes have been widely utilized for the fabrication of electrochemical biosensors. However, the biosensing electrode modified with ionic conducting solids remains unexplored. Herein, we prepared a superionic conducting potassium ferrite (K2Fe4O7) under hydrothermal conditions for modifying glassy carbon electrode (GCE). The modified electrode (K2Fe4O7/GCE) showed an excellent electrocatalytic activity towards the oxidation of dopamine (DA). The oxidation peak currents increased linearly with increasing DA concentrations in the range of 1 µM-140 µM, and the detection limit is 0.22 µM (S/N = 3). The developed DA sensor exhibited not only good selectivity for the determination of DA without interfering from ascorbic acid (AA), uric acid (UA), glucose and inorganic ions, but also good reproducibility and stability. Furthermore, the sensor was applied to determine DA concentration in bovine serum and obtained a satisfied result. This study provides a new approach for developing electrochemical biosensors based on ionic conducting solid materials.


Assuntos
Dopamina/sangue , Compostos Férricos/química , Potássio/química , Soroalbumina Bovina/química , Animais , Ácido Ascórbico/química , Técnicas Biossensoriais , Carbono/química , Bovinos , Condutividade Elétrica , Técnicas Eletroquímicas , Eletrodos , Glucose/química , Limite de Detecção , Oxirredução , Reprodutibilidade dos Testes , Propriedades de Superfície , Ácido Úrico/química
9.
J Nanosci Nanotechnol ; 20(4): 2104-2113, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-31492218

RESUMO

In this work, stable superparamagnetic core-shell Fe2B@SiO2 nanoparticles were prepared by "one pot" chemical reduction of ferric ion salts with NaBH4 and silica shell coating in the presence of citric acid stabilizer. The X-ray (XRD) and selection of electron diffraction (SAED) revealed that Fe2B@SiO2 nanoparticles were chiefly composed of silica shell and Fe2B with a small amount of α-Fe. Then, graphene oxide (GO) was assembled onto core-shell Fe2B@SiO2 nanoparticles for Epirubicin (EPI) loading and releasing, and the adsorption isotherm of EPI on Fe2B@SiO2@GO was analyzed. The results showed, the adsorption process includes two steps, due to the π-π stacking effect of EPI on the Fe2B@SiO2@GO. The EPI loading efficiency of the magnetic nanoparticles was as high as 90%, while the EPI-loaded core-shell Fe2B@SiO2 nanoparticles showed an obvious pH controlled drug release behavior, and showed lower cumulative release rate when pH is 7.4 than that when pH is 5.7. The prepared nanoparticles demonstrated potential application in killing tumor cells while minimizing the toxicity to normal tissues.


Assuntos
Grafite , Nanopartículas , Epirubicina , Dióxido de Silício
10.
Cell Mol Life Sci ; 77(4): 719-733, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31302752

RESUMO

Cytidine base editors (CBEs) have been demonstrated to be useful for precisely inducing C:G-to-T:A base mutations in various organisms. In this study, we showed that the BE4-Gam system induced the targeted C-to-T base conversion in porcine blastocysts at an efficiency of 66.7-71.4% via the injection of a single sgRNA targeting a xeno-antigen-related gene and BE4-Gam mRNA. Furthermore, the efficiency of simultaneous three gene base conversion via the injection of three targeting sgRNAs and BE4-Gam mRNA into porcine parthenogenetic embryos was 18.1%. We also obtained beta-1,4-N-acetyl-galactosaminyl transferase 2, alpha-1,3-galactosyltransferase, and cytidine monophosphate-N-acetylneuraminic acid hydroxylase deficient pig by somatic cell nuclear transfer, which exhibited significantly decreased activity. In addition, a new CBE version (termed AncBE4max) was used to edit genes in blastocysts and porcine fibroblasts (PFFs) for the first time. While this new version demonstrated a three genes base-editing rate of 71.4% at the porcine GGTA1, B4galNT2, and CMAH loci, it increased the frequency of bystander edits, which ranged from 17.8 to 71.4%. In this study, we efficiently and precisely mutated bases in porcine blastocysts and PFFs using CBEs and successfully generated C-to-T and C-to-G mutations in pigs. These results suggest that CBEs provide a more simple and efficient method for improving economic traits, reducing the breeding cycle, and increasing disease tolerance in pigs, thus aiding in the development of human disease models.


Assuntos
Citidina/genética , Edição de Genes/métodos , Suínos/genética , Animais , Blastocisto/metabolismo , Sistemas CRISPR-Cas , Galactosiltransferases/genética , Vetores Genéticos/genética , Oxigenases de Função Mista/genética , Mutagênese , N-Acetilgalactosaminiltransferases/genética , RNA Guia/genética , Suínos/embriologia
11.
Sci Rep ; 9(1): 18529, 2019 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-31811228

RESUMO

Coastal wetlands are terrestrial-marine transition zones harboring diverse active microbial communities. The origins of diverse glycerol ether lipids preserved in coastal wetlands are rarely investigated. 16 surface sediments were collected from the coastal wetland at Guangrao (GR), Changyi (CY) and Xiamen (XM), where both climate and sedimentary environment show significant differences. Ten groups of glycerol ether lipids, including isoprenoidal and branched glycerol dialkyl glycerol tetraethers (iGDGTs and bGDGTs), isoprenoidal and branched glycerol dialkanol diethers (iGDDs and bGDDs), hydroxylated isoprenoidal GDGTs and GDDs (OH-GDGTs and OH-GDDs), overly branched GDGTs (OB-GDGTs), sparsely branched GDGTs (SB-GDGTs), hybrid isoprenoid/branched GDGTs (IB-GDGTs) and a tentatively assigned H-shaped branched GDGTs (H-B-GDGTs) were detected and quantified. Sediments collected in the north (Guangrao and Changyi) contain, in general, a lower abundance of GDGT (3.7-55.9 ng/g sed) than samples from south (Xiamen; 251-1020 ng/g sed). iGDGTs and bGDGTs are the predominant components at all sites and account for 17.2-74.3% and 16.1-75.1% of total ether lipids, respectively. The relative abundance of iGDGTs decreases but that of bGDGTs increases with the distance from sea, suggesting a marine vs. terrestrial origin of iGDGT and bGDGTs, respectively. In addition, the methylation index (MIOB/B/SB) of branched GDGTs shows a significant inverse correlation with water content, suggesting that marine waters have a major influence on the microbial communities inhabiting wetland sediment. Such an assumption was confirmed by the distinct lipid pattern of three low water content (<5%) samples collected in an area isolated from tidal flushing. The other isoprenoidal ether lipids, such as iGDDs, OH-GDGTs and OH-GDGTs, have a similar distribution as iGDGTs, indicating a common biological source, so do the corresponding non-isoprenoidal ether lipid series with bGDGTs. The BIT value increases with increasing distance from the sea, which implies that the BIT index can be probably applied to trace past sea level change in costal wetland settings. The reconstructed temperature from TEX86 shows significant offset from observed data, but only little deviation for the MBT/CBT calculated temperature. This suggests that the MBT/CBT has the potential to reconstruct past temperatures in coastal wetland settings.

12.
Environ Sci Pollut Res Int ; 26(27): 28328-28340, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31372950

RESUMO

Chiral mesoporous silica (SiO2) with helical structure was synthesized by using anionic surfactants as template. Pre-prepared graphene oxide (GO) was then loaded onto SiO2 to synthesize composite carrier chial-meso-SiO2@GO for the immobilization of laccase. The enzyme activity, thermostability, acid stability, and repeatability of the immobilized enzyme were significantly improved after immobilization. The chial-meso-SiO2@GO-immobilized laccase was then used for the degradation of MXC in aqueous phase. The degradation conditions, including temperature, time, pH, MXC concentration, and the dose of immobilized enzyme for cellulosic hydrolysis, were optimized. The optimum conditions for degradation of methoxychlor were selected as pH 4.5, MXC concentration 30 mg/L, immobilized enzyme dose 0.1 g, the maximum MXC removal of over 85% and the maximum degradation rate of 50.75% were achieved after degradation time of six h at temperature of 45 °C. In addition, the immobilized cellulase was added into the immobilized laccase system to form chial-meso-SiO2@GO-immobilized compound enzyme with the maximum MXC degradation rate of 59.58%, higher than that of 50.75% by immobilized laccase. An assessment was made for the effect of chial-meso-SiO2@GO-immobilized compound enzyme on the degradation of MXC in soil phase. For three contaminated soils with MXC concentration of 25 mg/kg, 50 mg/kg, and 100 mg/kg, the MXC removals were 93.0%, 85.8%, and 65.1%, respectively. According to the GC-MS analyses, it was inferred that chial-meso-SiO2@GO-immobilized compound enzyme had a different degradation route with that of chial-meso-SiO2@GO-immobilized laccase. The hydrolysis by immobilized cellulase might attack at a weak location of the MXC molecule with its free radical OH and ultimately removed three chlorine atoms from MXC molecule, leading to generating small molecular amount of degradation product.


Assuntos
Enzimas Imobilizadas/metabolismo , Grafite/química , Lacase/metabolismo , Metoxicloro/química , Dióxido de Silício/química , Catálise , Poluição Ambiental , Solo , Temperatura , Água/química
13.
Mar Pollut Bull ; 149: 110497, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31430666

RESUMO

Three hundred five surface sediment samples from the Bohai Bay in northeastern China were examined for grain size, organic carbon (Corg) concentration, and concentrations of heavy metals (Pb, Zn, Cu, As, Cr, Cd, and Hg). Average metal concentrations were 33 mg/kg (Cu), 27 mg/kg (Pb), 95 mg/kg (Zn), 75 mg/kg (Cr), 0.3 mg/kg (Cd), 13 mg/kg (As), and 72 µg/kg (Hg). In most cases, these concentrations were lower than the China Marine Sediment Quality criteria. Enrichment factors, however, suggested moderate to strong Cd and Hg contamination of the Bohai Bay. The fact that 68.6% of Pollution Load Index (PLI) values exceeded 2 demonstrated strong pollution of the Bohai Bay, Hg contributed the most to the PLI.


Assuntos
Baías/química , Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Metais Pesados/análise , Poluentes Químicos da Água/análise , China , Medição de Risco
14.
Cell Mol Life Sci ; 76(20): 4155-4164, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31030226

RESUMO

Evolved xCas9(3.7) variant with broad PAM compatibility has been reported in cell lines, while its editing efficiency was site-specific. Here, we show that xCas9(3.7) can recognize a broad PAMs including NGG, NGA, and NGT, in both embryos and Founder (F0) rabbits. Furthermore, the codon-optimized xCas9-derived base editors, exBE4 and exABE, can dramatically improve the base editing efficiencies in rabbit embryos. Our results demonstrated that the optimized xCas9 with expanded PAM compatibility and enhanced base editing efficiency could be used for precise gene modifications in organisms.


Assuntos
Proteína 9 Associada à CRISPR/genética , Sistemas CRISPR-Cas , Efeito Fundador , Edição de Genes/métodos , Marcação de Genes/métodos , RNA Guia/genética , Animais , Animais Geneticamente Modificados , Proteína 9 Associada à CRISPR/metabolismo , Códon , Distrofina/genética , Distrofina/metabolismo , Embrião de Mamíferos , Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Microinjeções , Plasmídeos/química , Plasmídeos/metabolismo , Proteínas de Ligação a Poli(A)/genética , Proteínas de Ligação a Poli(A)/metabolismo , Presenilina-1/genética , Presenilina-1/metabolismo , RNA Guia/metabolismo , Coelhos , Repetições de Trinucleotídeos , Zigoto
15.
Inorg Chem ; 58(7): 4394-4398, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30869877

RESUMO

A new proton-conducting material (C6H14N2)[NiV2O6H8(P2O7)2]·2H2O (1) was hydrothermally synthesized by using 1,4-diazabicyclo[2,2,2]octane (DABCO) as the template. Its inorganic framework, determined by single crystal X-ray diffraction, is constructed by the connection of V/NiO6 octahedral to P2O7 pyrophosphate units through sharing oxygen atoms, giving rise to three-dimensional (3D) intersecting 6-, 8-, and 12-ring channels along the [100], [010], and [001] directions, respectively, in which there are ordered protonated DABCO cations balancing negative charge of the framework and disordered water molecules. Complex impedance measurements on polycrystalline samples gave proton conductivities of 4.9 × 10-3 and 2.0 × 10-2 S cm-1 at 25 and 60 °C under high humidity conditions, respectively. The activation energy is 0.38 eV.

16.
Molecules ; 24(3)2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30717129

RESUMO

A novel 3-D open-framework zinc borovanadate [Zn6(en)3][(VIVO)6(VVO)6O6(B18O36(OH)6)·(H2O)]2·14H2O (1, en = ethylenediamine) was hydrothermally obtained and structurally characterized. The framework was built from [V12B18O54(OH)6(H2O)]10- polyanion clusters bridged by Zn(en) complex fragments. The compound not only possessed a three-dimensional open-framework structure with unique plane-shaped channels, but also exhibited excellent catalytic activities for the oxidation of α-phenethyl alcohol.


Assuntos
Compostos de Boro/química , Álcool Feniletílico/química , Vanadatos/química , Zinco/química , Catálise , Cinética , Modelos Moleculares , Oxirredução
17.
Cells ; 8(2)2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30717310

RESUMO

Successful RNAi applications depend on strategies allowing stable and persistent expression of minimal gene silencing triggers without perturbing endogenous gene expression. In this study, we proposed an endogenous microRNA (miRNA) cluster as a novel integration site for small hairpin RNAs (shRNAs). We successfully integrated exogenous shRNAs at the porcine miRNA-17-92 (pmiR-17-92) cluster via a CRISPR/Cas9-mediated knock-in strategy. The anti-EGFP or anti-CSFV shRNAs could be stably and effectively expressed at the control of the endogenous promoter of the pmiR-17-92 cluster. Importantly, we confirmed that hitchhike expression of anti- classical swine fever (CSFV) shRNA had no effect on cell growth, blastocyst development and endogenous pmiR-17-92 expression in selected transgene (TG) porcine fetal fibroblasts (PFFs) clones. Moreover, these TG PFFs could inhibit the replication of CSFV by half and could be further used for generation of transgenic pigs. Taken together, these results show that our RNA interference (RNAi) expression strategy benefits numerous applications, from miRNA, genome and transgenic research, to gene therapy.


Assuntos
Proteína 9 Associada à CRISPR/metabolismo , Sistemas CRISPR-Cas/genética , MicroRNAs/genética , RNA Interferente Pequeno/metabolismo , Animais , Animais Geneticamente Modificados , Sequência de Bases , Blastocisto/metabolismo , Linhagem Celular , Feto/citologia , Fibroblastos/metabolismo , Genes Reporter , Genoma , Proteínas de Fluorescência Verde/metabolismo , MicroRNAs/metabolismo , RNA Guia/genética , Suínos , Transgenes
18.
PLoS Pathog ; 14(12): e1007193, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30543715

RESUMO

Classical swine fever (CSF) caused by classical swine fever virus (CSFV) is one of the most detrimental diseases, and leads to significant economic losses in the swine industry. Despite efforts by many government authorities to stamp out the disease from national pig populations, the disease remains widespread. Here, antiviral small hairpin RNAs (shRNAs) were selected and then inserted at the porcine Rosa26 (pRosa26) locus via a CRISPR/Cas9-mediated knock-in strategy. Finally, anti-CSFV transgenic (TG) pigs were produced by somatic nuclear transfer (SCNT). Notably, in vitro and in vivo viral challenge assays further demonstrated that these TG pigs could effectively limit the replication of CSFV and reduce CSFV-associated clinical signs and mortality, and disease resistance could be stably transmitted to the F1-generation. Altogether, our work demonstrated that RNA interference (RNAi) technology combining CRISPR/Cas9 technology offered the possibility to produce TG animal with improved resistance to viral infection. The use of these TG pigs can reduce CSF-related economic losses and this antiviral strategy may be useful for future antiviral research.


Assuntos
Antivirais , Peste Suína Clássica/prevenção & controle , Engenharia Genética/métodos , Animais , Animais Geneticamente Modificados , Vírus da Febre Suína Clássica , Suínos
19.
Mar Pollut Bull ; 136: 300-308, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30509811

RESUMO

Concentrations of arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), mercury (Hg), lead (Pb), and zinc (Zn), grain sizes, and concentrations of organic carbon (Corg) were measured in 323 river sediment samples from the Pearl River Delta (PRD). Results showed that the heavy metal concentrations in the sediments ranged from 1.6-93 mg/kg for As, 0.04-9.3 mg/kg for Cd, 2-315 mg/kg for Cr, 1.1-352 mg/kg for Cu, 0.01-0.67 mg/kg for Hg, 11-221 mg/kg for Pb, and 11-1234 mg/kg for Zn. The highest values of As, Cr, Cu, Hg, Pb, and Zn appeared in the Beijiang River, whereas Cd was high in the Xijiang River. The overall sediment quality in the area with respect to metal concentrations generally met the primary standard criteria of China (Marine Sediment Quality), except for Cd and Cu. The spatial distributions of the heavy metals were influenced by both grain sizes and Corg concentrations. The Igeo geo-accumulation index indicated that there was no significant Cr, Cu, Hg, or Zn pollution, slight to moderate pollution by As and Pb, and moderate Cd pollution in the study area. Spatial distributions of an eco-toxicological index based on probable effect levels indicated that there was a 21% probability that the combination of the seven metals was exerting a toxic stress in the PRD river sediments.


Assuntos
Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Metais Pesados/análise , Rios/química , Poluentes Químicos da Água/análise , China , Propriedades de Superfície
20.
ACS Appl Mater Interfaces ; 10(47): 40568-40576, 2018 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-30378420

RESUMO

Ni3S2 nanosheets doped with tin (Sn) grown on nickel foam (Sn-Ni3S2/NF) through a facile hydrothermal process were found to be superior water-splitting electrocatalysts. As for overall water splitting (OWS), when the current density is 10 mA cm-2, the required voltage is only 1.46 V. Meanwhile, it exhibits a large current density property and long-time stability (>60 h current-time tests) for both the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER). In order to reach the current densities of 100 and 1000 mA cm-2, Sn-Ni3S2/NF needs overpotentials of 0.17 and 0.57 V for HER, and 0.27 and 0.58 V for OER, respectively. The water-splitting property of Sn-Ni3S2/NF is much better than that of pure Ni3S2/NF or even 20 wt % Pt/C/NF and RuO2/NF. Furthermore, Sn-Ni3S2/NF showed a higher turnover frequency at different potentials, with ∼100% Faraday efficiency for both O2 and H2. The improved activity of Sn-Ni3S2/NF activity for water-splitting is attributed to the doping of Sn, which enhanced the intrinsic activity of Sn-Ni3S2/NF for OWS. This article not only provides a new efficient and stable catalyst for OWS, but also proposes an interface design principle for NF-based high-performance water-splitting materials.

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