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1.
Angew Chem Int Ed Engl ; 59(1): 172-176, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31595640

RESUMO

Single-ligand-based electronically conductive porous coordination polymers/metal-organic frameworks (EC-PCPs/MOFs) fail to meet the requirements of numerous electronic applications owing to their limited tunability in terms of both conductivity and topology. In this study, a new 2D π-conjugated EC-MOF containing copper units with mixed trigonal ligands was developed: Cu3 (HHTP)(THQ) (HHTP=2,3,6,7,10,11-hexahydrotriphenylene, THQ=tetrahydroxy-1,4-quinone). The modulated conductivity (σ≈2.53×10-5  S cm-1 with an activation energy of 0.30 eV) and high porosity (ca. 441.2 m2 g-1 ) of the Cu3 (HHTP)(THQ) semiconductive nanowires provided an appropriate resistance baseline and highly accessible areas for the development of an excellent chemiresistive gas sensor.

2.
Accid Anal Prev ; 136: 105400, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31869694

RESUMO

Recent field data analyses have shown that lumbar spine fractures occurred more frequently in late model vehicles than the early ones in frontal crashes. Therefore, the objective of this study was to investigate risk factors associated with lumbar spine fractures in frontal crashes. Parametric simulations were conducted using a set of validated vehicle driver compartment model, restraint system model, and a HIII mid-size male crash test dummy model. Risk factors considered in the study included occupant seating posture, crash pulse, vehicle pitch angle, seat design, anchor pre-tensioner, dynamic locking tongue, and shoulder belt load limiter. ANOVA and ANCOVA were used to test the statistical significance (p < 0.05). Simulation results showed that all the factors that reduced the risk of submarining increased the lumbar spine forces, indicating a direct conflict between submarining and lumbar spine fractures. Among all the factors selected, seat structure is the most significant factor in determining the lumbar spine force (p < 0.001). Crash pulse severity, time at which the peak crash deceleration reached, and pitch angle are also crucial for lumbar spine force. Specifically, increase in vehicle pitch angle increased lumbar spine force, but reduced injury measures to other body regions; while a crash pulse with early peak produced greater lumbar spine force than that with a late peak. On average, more reclined posture increased the lumbar spine force compared to upright posture, and decreases in the coefficient of friction between the pelvis and the seat cushion reduced the lumbar spine force. However, they are not statistically significant. This study provided better understanding of effects from design countermeasures to reduce occupant lumbar spine injuries in new generation of vehicle models.

3.
Opt Express ; 27(26): 37900-37909, 2019 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-31878563

RESUMO

We investigate the microstructural characteristics and optical properties of PbS quantum dots-doped silica fiber (PQDF), prepared by atomic layer deposition (ALD) doping technique. The fiber exhibits ultra-wideband luminescence and flat-gain with 3 dB bandwidth of 300 nm. The on-off gain and net gain can reach to 7.1-15.0 dB and 6.0-9.2 dB at 1050-1350 nm, respectively. The results of high-resolution transmission electron microscopy (HRTEM) further reveal the effects of PbS QDs doping in PQDF. The broadband luminescence spectrum originating from three active centers (1086, 1179, and 1304 nm), can be attributed to the dimension effect of PbS QDs (3.7, 4.0, and 4.3 nm, respectively). Moreover, the calculation results indicate that the multi-sized PbS QDs concentrated at 3.65-4.45 nm make the 3 dB gain bandwidth increase, which is six times wider than that of traditional erbium-doped fiber (EDF). Therefore, this type of PQDF is a promising gain medium for optical amplifiers and broadband light sources.

4.
World J Clin Cases ; 7(20): 3175-3184, 2019 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-31667167

RESUMO

BACKGROUND: Antibiotic resistance has become a global threat for human health, calling for rational use of antibiotics. AIM: To analyze the distribution and drug resistance of the bacteria, providing the prerequisite for use of antibiotics in emergency patients. METHODS: A total of 2048 emergency patients from 2013 to 2017 were enrolled. Their clinical examination specimens were collected, followed by isolation of bacteria. The bacterial identification and drug susceptibility testing were carried out. RESULTS: A total of 3387 pathogens were isolated. The top six pathogens were Acinetobacter baumannii (660 strains), Staphylococcus aureus (436 strains), Klebsiella pneumoniae (347 strains), Pseudomonas aeruginosa (338 strains), Escherichia coli (237 strains), and Candida albicans (207 strains). The isolation rates of these pathogens decreased year by year except Klebsiella pneumoniae, which increased from 7.1% to 12.1%. Acinetobacter baumannii is a widely-resistant strain, with multiple resistances to imipenem, ciprofloxacin, minocycline and tigecycline. The Staphylococcus aureus had high resistance rates to levofloxacin, penicillin G, and tetracycline. But the susceptibility of it to vancomycin and tigecycline were 100%. Klebsiella pneumoniae had high resistance rates to imipenem, cefoperazone/sulbactam, amikacin, and ciprofloxacin, with the lowest resistance rate to tigecycline. The resistance rates of Pseudomonas aeruginosa to cefoperazone/sulbactam and imipenem were higher, with the resistance rate to amikacin below 10%. Besides, Escherichia coli had high resistance rates to ciprofloxacin and cefoperazone/sulbactam and low resistance rates to imipenem, amikacin, and tigecycline. CONCLUSION: The pathogenic bacteria isolated from the emergency patients were mainly Acinetobacter baumannii, Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa, Escherichia coli, and Candida albicans. The detection rates of drug-resistant bacteria were high, with different bacteria having multiple drug resistances to commonly used antimicrobial agents, guiding the rational use of drugs and reducing the production of multidrug-resistant bacteria.

5.
Drug Deliv ; 26(1): 1178-1190, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31738084

RESUMO

Poor initial stability at the first four weeks after surgery is becoming the major causes for metal implant failure. Previous attempts neglected the control release of insulin for the bone regeneration among nondiabetic subjects. The major reason may lie in the adverse effects, such as attenuated bone formation, hypoglycemia or hyperinsulinemia, that caused by the excessive insulin. Thus, spatiotemporal release of insulin may serve as the promising strategy. To address this, through solvent extraction (EMS), solvent evaporation (SMS) and cosolvent methods (CMS), we prepared three types of PLGA microspheres with various internal structures, but similar size distribution. The effects of the preparation methods on the properties of the microspheres, such as their release behavior, degradation of molecular weight, and structural evolution, were investigated. Human bone marrow mesenchymal stromal cells (BMSCs) and rabbit implant models were used to test the bioactivity of the microspheres in vitro and in vivo, respectively. The result demonstrated that these three preparation methods did not influence the polymer degradation but instead affected the internal structural evolution, which plays a crucial role in the release behavior, osteogenesis and peri-implant bone regeneration. Compared with EMS and CMS microspheres, SMS microspheres exhibited a relatively steady release rate in the first four weeks, which evidently stimulated the osteogenic differentiation of the stem cells and peri-implant bone regeneration. Meanwhile, SMS microspheres significantly enhanced the stability of the implant at Week 4, which is promising to reduce early failure rate of the implant without inducing adverse effects on the serum biochemical indices.

6.
Nat Commun ; 10(1): 4362, 2019 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-31554816

RESUMO

Direct structural information of confined CO2 in a micropore is important for elucidating its specific binding or activation mechanism. However, weak gas-binding ability and/or poor sample crystallinity after guest exchange hindered the development of efficient materials for CO2 incorporation, activation and conversion. Here, we present a dynamic porous coordination polymer (PCP) material with local flexibility, in which the propeller-like ligands rotate to permit CO2 trapping. This process can be characterized by X-ray structural analysis. Owing to its high affinity towards CO2 and the confinement effect, the PCP exhibits high catalytic activity, rapid transformation dynamics, even high size selectivity to different substrates. Together with an excellent stability with turnover numbers (TON) of up to 39,000 per Zn1.5 cluster of catalyst after 10 cycles for CO2 cycloaddition to form value-added cyclic carbonates, these results demonstrate that such distinctive structure is responsible for visual CO2 capture and size-selective conversion.

7.
Front Immunol ; 10: 1647, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31379845

RESUMO

Background: Antibody-dependent cellular cytotoxicity (ADCC), which mainly mediated by natural killer (NK) cells, may play a critical role in human immunodeficiency virus type-1 (HIV-1) disease progression. However, the potential mechanisms that affecting NK-mediated ADCC response are still not well-elucidated. Methods: Antigen-antibody complex model of Ab-opsonized P815 cells was adopted to induce a typical non-specific ADCC response. The capacities of HIV-1 specific NK-ADCC were measured by using the combination model of gp120 protein and plasma of HIV-1 elite controllers. The levels of plasma cytokine were measured by ELISA. Anti-IL-2 blocking antibody was used to analyze the impact of activated CD56+ T cells on NK-ADCC response. Results: IL-2, IL-15, IFN-α, and IFN-ß could effectively enhance the non-specific and HIV-1-specific NK-ADCC responses. Compared with healthy controls, HIV-1-infected patients showed decreased plasma IL-2 levels, while no differences of plasma IFN-α, IL-15, and IFN-ß were presented. IL-2 production was detected from CD56+ T cells activated through antibody-dependent manner. The capability of NK-ADCC could be weakened by blocking IL-2 secretion from activated CD56+ T cells. Although no difference of frequencies of CD56+ T cells was found between HIV-1-infected patients and healthy controls, deficient IL-2 secretion from activated CD56+ T were found in chronic HIV-1 infection. Conclusions: The impaired ability of activated CD56+ T cells to secreting IL-2 might contribute to the attenuated NK cell-mediated ADCC function in HIV-1 infection.

8.
Dalton Trans ; 48(31): 11855-11861, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31305832

RESUMO

A novel squaramide-containing metal-organic framework (MOF) material has been designed and synthesized. A detailed X-ray crystal structure analysis showed that four squaramides of this MOF adopted two orientations in each dependent nanopore, confirming that two carbonyl and two N-H groups pointed simultaneously to the inside of the one-dimensional nanometer channel. The MOF was applied as an efficient bifunctional hydrogen-bonding catalyst for Michael additions of 1,3-dicarbonyl compounds to nitroalkenes in pure water, boosting the catalytic efficiency by up to approximately five times the value afforded by the homogeneous control and exhibiting a highly size-selective catalytic performance and good renewability. The catalytic mechanism was also discussed in detail. The present study provides a highly promising approach to achieving dual-activation catalytic centers in a single system, which function as microscopic chemical reactors that allow the interaction and fast transport of substrate molecules in their cavities.

9.
ACS Appl Mater Interfaces ; 11(23): 21086-21093, 2019 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-31091075

RESUMO

Due to the extremely high number of accessible active sites and short diffusion path, porous coordination polymer (PCP) nanosheets have demonstrated a variety of promising applications, especially for energy conversion and mass transfer. However, the development of chemically stable PCP nanosheets with dense active sites and large lateral size is a great challenge in terms of feasible considerations. Herein, we first designed and prepared a kind of chemically stable PCP nanosheets via a bottom-up and a top-down integral strategy. Featuring densely exposed and periodic Cu2+ active sites (2.1 × 106 per µm2), as well as ultrathin nature (5 nm) and significant pores (18 Å), this nanosheet demonstrated remarkable performance of electrocatalytic hydrogen evolution. Furthermore, one plausible process and the effect of Cu2+ active sites were proposed and validated by density functional theory calculations.

11.
Oxid Med Cell Longev ; 2019: 3415682, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31007833

RESUMO

Aims: Vascular calcification (VC) is a primary risk factor for cardiovascular mortality in chronic renal failure (CRF) patients; thus, effective therapeutic targets are urgently needed to be explored. Here, we identified the role of intestinal bacterial translocation in CRF-related VC. Methods and Results: Antibiotic supplementation by oral gavage significantly suppressed intestinal bacterial translocation, CRF-related VC, and aortic osteogenic gene and Toll-like receptor (TLR) gene expression in CRF rats. Furthermore, TLR4 and TLR9 activation in vascular smooth muscle cells (VSMCs) aggravated inorganic phosphate- (Pi-) induced calcification. TLR9 inhibition, but not TLR4 inhibition, by both a pharmacological inhibitor and genetic methods could significantly reduce CRF rats' serum or CRF-induced VC. Interestingly, bone morphogenic protein-2 (BMP-2) levels were increased in the aorta and sera from CRF rats. Increased BMP-2 levels were also observed in VSMCs treated with TLR9 agonist, which was blocked by NF-κB inhibition. Both siRNA knockdown of BMP-2 and NF-κB inhibitor significantly blocked TLR9 agonist-induced VSMC calcification. Conclusions: Gut bacterial translocation inhibited by oral antibiotic significantly reduces CRF-related VC through inhibition of TLR9/NF-κB/BMP-2 signaling.


Assuntos
Translocação Bacteriana , Proteína Morfogenética Óssea 2/metabolismo , Microbioma Gastrointestinal , Receptor Toll-Like 9/metabolismo , Calcificação Vascular/metabolismo , Calcificação Vascular/microbiologia , Animais , Antibacterianos/administração & dosagem , Antibacterianos/farmacologia , Translocação Bacteriana/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , DNA Bacteriano/metabolismo , Microbioma Gastrointestinal/efeitos dos fármacos , Humanos , Inflamação/patologia , Lipopolissacarídeos/farmacologia , Masculino , Camundongos Endogâmicos C57BL , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/metabolismo , NF-kappa B/metabolismo , Osteoblastos/citologia , Ratos Wistar , Insuficiência Renal Crônica/microbiologia , Insuficiência Renal Crônica/patologia , Transdução de Sinais
12.
Inorg Chem ; 58(8): 4894-4906, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30946577

RESUMO

The unique Rh-Al bond in recently synthesized Rh(PAlP) 1 {PAlP = pincer-type diphosphino-aluminyl ligand Al[NCH2(P iPr2)]2(C6H4)2NMe} was investigated using the DFT method. Complex 1 has four doubly occupied nonbonding d orbitals on the Rh atom and one Rh d orbital largely participating in the Rh-Al bond which exhibits considerably large bonding overlap between Rh and Al atoms like in a covalent bond. Interestingly, Rhδ--Alδ+ polarization is observed in the bonding MO of 1, which is reverse to Rhδ+-Eδ- (E = coordinating atom) polarization found in a usual coordinate bond. This unusual polarization arises from the presence of the Al valence orbital at significantly higher energy than the Rh valence orbital energy. Characteristic features of 1 are further unveiled by comparing 1 with similar Rh complexes RhL(PMe3)2 (2 for L = AlMe2, 3 for L = Al(NMe2)2, 4 for L = BMe2, 5 for L = SiMe3, 6 for L = SiH3, 7 for L = CH3, 8 for L = OMe, and 9 for L = Cl). As expected, 7, 8, and 9 exhibit usual Rhδ+-Eδ- polarization (E = coordinating atom) in the Rh-E bonding MO. On the other hand, the reverse Rhδ--Eδ+ polarization is observed in the Rh-E bonding MOs of 2-5 like in 1, while the Rh-Si bond is polarized little in 6. These results are clearly understood in terms of the valence orbital energy of the ligand. Because the LUMO of 1 mainly consists of the Rh 4dσ, 5s, and 5p orbitals and the Al 3s and 3p orbitals, both Rh and Al atoms play the role of coordinating site for a substrate bearing a lone pair orbital. For instance, NH3 and pyridine coordinate to both Al and Rh atoms with considerably large binding energy. PAlP exhibits significantly strong trans influence, which is as strong as that of SiMe3 but moderately weaker than that of BMe2. The trans influence of these ligands is mainly determined by the valence orbital energy of the ligand and the covalent bond radius of the coordinating E atom.

13.
Science ; 363(6425): 387-391, 2019 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-30679369

RESUMO

Design of the gas-diffusion process in a porous material is challenging because a contracted pore aperture is a prerequisite, whereas the channel traffic of guest molecules is regulated by the flexible and dynamic motions of nanochannels. Here, we present the rational design of a diffusion-regulatory system in a porous coordination polymer (PCP) in which flip-flop molecular motions within the framework structure provide kinetic gate functions that enable efficient gas separation and storage. The PCP shows substantial temperature-responsive adsorption in which the adsorbate molecules are differentiated by each gate-admission temperature, facilitating kinetics-based gas separations of oxygen/argon and ethylene/ethane with high selectivities of ~350 and ~75, respectively. Additionally, we demonstrate the long-lasting physical encapsulation of ethylene at ambient conditions, owing to strongly impeded diffusion in distinctive nanochannels.

14.
J Am Chem Soc ; 140(42): 13958-13969, 2018 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-30264569

RESUMO

The gate-opening adsorption mechanism and sigmoidal adsorption isotherm were theoretically investigated taking CO2 adsorption into porous coordination polymers, [Fe(ppt)2] n (PCP-N, Hppt = 3-(2-pyrazinyl)-5-(4-pyridyl)-1,2,4-triazole) and [Fe(dpt)2] n (PCP-C, Hdpt = 3-(2-pyridinyl)-5-(4-pyridyl)-1,2,4-triazole) as examples, where the hybrid method consisting of dispersion-corrected DFT for infinite PCP and a post-Hartree-Fock (SCS-MP2 and CCSD(T)) method for the cluster model was employed. PCP-N has site I (one-dimensional channel), site II (small aperture to site I), and site III (small pore) useful for CO2 adsorption. CO2 adsorption at site I occurs in a one by one manner with a Langmuir adsorption isotherm. CO2 adsorption at sites II and III occurs through a gate-opening adsorption mechanism, because the crystal deformation energy ( EDEF) at these sites is induced largely by the first CO2 adsorption but induced much less by the subsequent CO2 adsorption. Interestingly, nine CO2 molecules are adsorbed simultaneously at these sites because a large EDEF cannot be overcome by adsorption of one CO2 molecule but can be by simultaneous adsorption of nine CO2 molecules. For such CO2 adsorption, the Langmuir-Freundlich sigmoidal adsorption isotherm was derived from the equilibrium equation for CO2 adsorption. A very complicated CO2 adsorption isotherm, experimentally observed, is reproduced by combination of the Langmuir and Langmuir-Freundlich adsorption isotherms. In PCP-C, CO2 adsorption occurs only at site I with the Langmuir adsorption isotherm. Sites II and III of PCP-C cannot be used for CO2 adsorption because a very large EDEF cannot be overcome by simultaneous adsorption of nine CO2 molecules. Factors necessary for gate-opening adsorption mechanism are discussed on the basis of differences between PCP-N and PCP-C.

15.
Front Plant Sci ; 9: 610, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29868067

RESUMO

Soybean was domesticated about 5,000 to 6,000 years ago in China. Although genotyping technologies such as genotyping by sequencing (GBS) and high-density array are available, it is convenient and economical to genotype cultivars or populations using medium-density SNP array in genetic study as well as in molecular breeding. In this study, 235 cultivars, collected from China, Japan, USA, Canada and some other countries, were genotyped using SoySNP8k iSelect BeadChip with 7,189 single nucleotide polymorphisms (SNPs). In total, 4,471 polymorphic SNP markers were used to analyze population structure and perform genome-wide association study (GWAS). The most likely K value was 7, indicating this population can be divided into 7 subpopulations, which is well in accordance with the geographic origins of cultivars or accession studied. The LD decay rate was estimated at 184 kb, where r2 dropped to half of its maximum value (0.205). GWAS using FarmCPU detected a stable quantitative trait nucleotide (QTN) for hilum color and seed color, which is consistent with the known loci or genes. Although no universal QTNs for flowering time and maturity were identified across all environments, a total of 30 consistent QTNs were detected for flowering time (R1) or maturity (R7 and R8) on 16 chromosomes, most of them were corresponding to known E1 to E4 genes or QTL region reported in SoyBase (soybase.org). Of 16 consistent QTNs for protein and oil contents, 11 QTNs were detected having antagonistic effects on protein and oil content, while 4 QTNs soly for oil content, and one QTN soly for protein content. The information gained in this study demonstrated that the usefulness of the medium-density SNP array in genotyping for genetic study and molecular breeding.

16.
Appl Bionics Biomech ; 2018: 8626102, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29849762

RESUMO

Recent field data showed that lumbar spine fractures occurred more frequently in late model vehicles than early ones in frontal crashes. However, the lumbar spine designs of the current crash test dummies are not accurate in human anatomy and have not been validated against any human/cadaver impact responses. In addition, the lumbar spines of finite element (FE) human models, including GHBMC and THUMS, have never been validated previously against cadaver tests. Therefore, this study developed a detailed FE lumbar spine model and validated it against cadaveric tests. To investigate the mechanism of lumbar spine injury in frontal crashes, effects of changing the coefficient of friction (COF), impact velocity, cushion thickness and stiffness, and cushion angle on the risk of lumbar spine injuries were analyzed based on a Taguchi array of design of experiments. The results showed that impact velocity is the most important factor in determining the risk of lumbar spine fracture (P = 0.009). After controlling the impact velocity, increases in the cushion thickness can effectively reduce the risk of lumbar spine fracture (P = 0.039).

17.
Phys Chem Chem Phys ; 20(21): 14671-14678, 2018 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-29770408

RESUMO

Recent reports pointed out that the formal La2C2n (2n = 92-106) series can exist stably as carbide cluster metallofullerenes (CCMFs) La2C2@C2n-2 with their successful crystallographic characterization. Herein, we suggest that the corresponding dimetallofullerenes (di-EMFs) La2@C2n possessing the lowest potential energies are also plausible candidates because of their favorability in statistical thermodynamics. This can be demonstrated in our present theoretical investigations on La2C94 and previously reported other La2C2n (2n = 92, 96-100) series by density functional theory calculations and statistical mechanics analyses. Nevertheless, it was noted that these thermodynamically favorable La2@C2n isomers turned out to be kinetically unstable radicals due to the presence of one unpaired electron on the carbon cage, making them missing fullerenes and difficult to be captured in their pristine forms, except for the experimentally obtained La2@D5(450)-C100 that has no unpaired electron. Such kinetic instability could be modified by electron reduction (the products were denoted as [La2@C2n]-) or other similar exterior functionalization with ˙CF3 and benzyl radicals, resulting in La-La bonded and paramagnetic species capable of being captured. On the basis of these approaches, carbon cages D3(85)-C92, Cs(120)-C94, D2(186)-C96, and C2(157)-C96 are predicted to be feasibly captured as both pristine CCMF species and electron reduced di-EMF derivatives.

18.
Gene ; 663: 1-8, 2018 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-29660520

RESUMO

Atherosclerosis is a vascular disease associated with ageing, and its occurrence and development are closely related to the vascular inflammatory response. Oxidized low-density lipoprotein (oxLDL) has distinct effects in atherosclerosis. We aimed to determine the mechanisms underlying these effects. microRNAs including miR-758 were differentially expressed in oxLDL-treated HUVECs or HAECs. Luciferase reporter assay results indicated that SUCNR1 is an important target of miR-758. Expression of SUCNR1 and its downstream components was decreased significantly in ApoE-/- mice. Overexpression of miR-758 could suppress HUVEC proliferation by cell cycle arrest at the G0/G1 phase. miR-758 was overexpressed on HUVECs with markedly reduced capillary tubule formation capacity. Overexpression of miR-758 on HUVECs or HAECs could significantly reduce SUCNR1 (GPR91), SATA3, phosphorylated STAT3 (p-STAT3), and EVGF levels. Thus, oxLDL likely damages vascular endothelial cells by modulating the DLK1-DIO3 genomic imprinted microRNA cluster component miR-758, thereby suppressing expression of SUCNR1/GPR91 and its downstream components.


Assuntos
Aterosclerose/genética , Endotélio Vascular/citologia , Lipoproteínas LDL/farmacologia , MicroRNAs/genética , Receptores Acoplados a Proteínas-G/genética , Animais , Apolipoproteínas E/genética , Aterosclerose/metabolismo , Pontos de Checagem do Ciclo Celular , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Células Endoteliais/metabolismo , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , Camundongos , Regiões Promotoras Genéticas , Receptores Acoplados a Proteínas-G/metabolismo , Fator de Transcrição STAT3/metabolismo
19.
Chemistry ; 24(24): 6412-6417, 2018 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-29419938

RESUMO

Two porous coordination polymers (PCPs) with different topologies (NTU-19: sql and NTU-20: dia) underwent finely controlled, stepwise crystal conversions to yield a common water-stable, flexible 2D framework (NTU-22: kgm). The crystal conversions occurred directly at higher temperature via the 3D intermediate (NTU-21: nbo), which could be observed at lower temperature. The successful isolation of the intermediate product of NTU-21, characterization with in situ PXRD and UV/Vis spectra were combined with DFT calculations to allow an understanding of the dynamic processes at the atomic level. Remarkably, breakthrough experiments demonstrate NTU-22 with integral structural properties allowed significant CO2 /CH4 mixture separation.

20.
J Cell Mol Med ; 22(4): 2299-2310, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29411538

RESUMO

In this study, a bioinformatics analysis and luciferase reporter assay revealed that microRNA-141 could silence the expression of lncRNA-HOTAIR by binding to specific sites on lncRNA-HOTAIR. We used superparamagnetic iron oxide nanoparticles (SPIONs) to mediate the high expression of microRNA-141 (SPIONs@miR-141) in human amniotic epithelial stem cells (HuAESCs), which was followed by the induction of the differentiation of HuAESCs into dopaminergic neuron-like cells (iDNLCs). qPCR, western blot, immunofluorescence staining and HPLC all suggested that SPION-mediated overexpression of miR-141 could promote an increased expression of brain-derived neurotrophic factor (BDNF), DAT and 5-TH in HuAESC-derived iDNLCs. The RIP and ChIP assay also showed that overexpression of miR-141 could significantly inhibit the recruitment and binding of lncRNA-HOTAIR to EZH2 on BDNF gene promoter. cDNA microarray analysis revealed that the expression levels of 190 genes were much higher in iDNLCs than in HuAESCs. Finally, a protein interaction network analysis and identification showed that in the iDNLC group with SPIONs@miR-141, factors that interact with BDNF, such as FGF8, SHH, NTRK3 and CREB1, all showed significantly higher expression levels compared with those in the SPIONs@miR-Mut. Therefore, this study confirmed that the highly efficient expression of microRNA-141 mediated by SPIONs could improve the efficiency of HuAESCs differentiation into dopaminergic neuron-like cells.


Assuntos
Diferenciação Celular/genética , Neurônios Dopaminérgicos/citologia , MicroRNAs/genética , Linhagem Celular , Proliferação de Células/genética , Biologia Computacional , Neurônios Dopaminérgicos/metabolismo , Células Epiteliais/efeitos dos fármacos , Compostos Férricos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Luciferases/química , Nanopartículas/administração & dosagem , Regiões Promotoras Genéticas
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