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1.
Appl Opt ; 58(27): 7311-7318, 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31674375

RESUMO

Precision glass molding (PGM) has become a viable processing method for large-volume aspheric optical elements. The optimization of a PGM process is an obstacle to the realization of mass production. The current work is focused on optimizing the process parameters to gain satisfactory surface shape. But the machining cycle time is not optimized. When setting the process route in the machine interface, going to the next step after reaching the target temperature rather than reaching the target time is usually set for the heating and cooling phase. Thus, the time to complete the heating and cooling stages of the production cycle is known only in the actual production. As for chalcogenide glass, its physical and chemical properties are greatly dependent on temperature. So, it is necessary to effectively simulate these stages to obtain the cost in time for actual production. Due to the excellent availability of numerical simulation, the rapid development of computing technology, and the increase of task scale in data and information processing, the finite element method can be applied to simulate the whole molding process. In this paper, a heat transfer model is established with the partial differential equation toolbox in MATLAB software. MSC.Marc software is used to simulate the heating stage at the same time. The numerical results are consistent, indicating that the heat transfer model established in MATLAB is, at least to a certain extent, valid. The heat transfer model needs further improvement by considering temperature-dependent properties such as viscoelasticity to make it a more effective tool for process analysis and optimization.

2.
Biomolecules ; 9(11)2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31653005

RESUMO

Dermaseptins are an antimicrobial peptide family widely identified from the skin secretions of phyllomeudusinae frogs. Here, we identify Dermaseptin-PC (DM-PC), from the skin secretion of Phyllomedusa coelestis, and further investigate the properties of this peptide, and a number of rationally designed truncated derivatives. The truncated 19-mer derived from the N-terminus exhibited similar antimicrobial potency when compared to the parent peptide, but the haemolytic effect of this truncated peptide was significantly decreased. Based on previous studies, the charge and hydrophobicity of truncated derivatives can affect the bioactivity of these peptides and thus we designed a 10-mer derivative with an optimised positive charge and a cyclohexylalanine (Cha) at the C-terminus for enhancing the hydrophobicity, DMPC-10A, which retained the antimicrobial activity of the parent peptide. To further investigate the influence of Cha at the C-terminus on activity, it was substituted by alanine (Ala) to generate another derivative, DMPC-10, but this was found to be much less potent. In addition, DM-PC, DMPC-19 and DMPC-10A not only rapidly killed planktonic bacteria isolated from cystic fibrosis (CF) patient, but also effectively eradicated their biofilm matrices.

3.
Sci Rep ; 9(1): 14322, 2019 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-31586086

RESUMO

Simultaneous removal of NOx and SO2 during the wet absorption process has made it possible for nitrogen resource utilization. However, nitrites formation at high ratio in absorption solution would limit its application. In this study, the catalytic oxidation behaviors of aqueous nitrite ions assisted by ozone on HZSM-5 zeolites with different SiO2/Al2O3 ratios have been investigated. The experimental results revealed that the oxidation and disproportionation reactions of nitrite ions took place competitively, both of which were accelerated under acidic condition. Moreover, the introduction of HZSM-5 zeolites and ozone would significantly improve the nitrite oxidation rate, where the zeolites with high SiO2/Al2O3 ratios were found to be more effective owing to the enhanced adsorption of nitrite ions and ozone. Based on the results under different operating conditions (such as O3 concentration, HZSM-5 dosage, pH values and presence of radical scavengers etc.), the reaction mechanism was then proposed. The disproportionation reaction of nitrite ions mainly occurred in the bulk solution. And the catalytic oxidation of nitrite ions over zeolites proceeded via a non-radical surface reaction between the adsorbed nitrite ions and ozone/oxygen molecular.

4.
Opt Lett ; 44(19): 4817-4820, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31568450

RESUMO

We demonstrate an enhanced efficiency of all-inorganic perovskite light-emitting diodes (PeLEDs) by doping an electron acceptor of 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4-TCNQ) as a p-type dopant into the hole-transport layer (HTL) of poly-triarylamine (PTAA). The conductivity of the PTAA was improved by the formation of the CT complex through the electron transfer from the PTAA to F4TCNQ. Moreover, the hydrophobic surface of the PTAA leads to an improved surface morphology of the perovskite films compared to that on the conventionally used HTL of PEDOT:PSS. As a result, the maximum luminance and efficiency for the doped PTAA-based PeLEDs are 28020 cd/m2 and 13.5 cd/A, respectively, corresponding to 32.7% and 48% improvement in the efficiency compared to those of the pure PTAA or PEDOT:PSS-based PeLEDs.

5.
Phys Rev Lett ; 123(12): 122501, 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31633953

RESUMO

Fission product yields are key infrastructure data for nuclear applications in many aspects. It is a challenge both experimentally and theoretically to obtain accurate and complete energy-dependent fission yields. We apply the Bayesian neural network (BNN) approach to learn existing fission yields and predict unknowns with uncertainty quantification. We demonstrated that the BNN is particularly useful for evaluations of fission yields when incomplete experimental data are available. The BNN evaluation results are quite satisfactory on distribution positions and energy dependencies of fission yields.

6.
Artigo em Inglês | MEDLINE | ID: mdl-31634416

RESUMO

Acid-functionalization of carbon support allows enhancing the electrocatalytic activity of Pd to hydrogenate benzaldehyde to benzyl alcohol in proportion to the concentration of Brønsted acid sites. In contrast, the hydrogenation rate is not affected when H 2 is used as reduction equivalent. The different response to catalyst properties is shown to be caused by differences in the hydrogenation mechanism between the electrochemical and the H 2 induced hydrogenation pathways. The enhancement of the electrocatalytic reduction is realized by the participation of support generated hydronium ions at the perimeter of metal particles.

7.
Cancer Biol Ther ; : 1-9, 2019 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-31564196

RESUMO

CD16a (FcγRIIIa) mediates the antibody dependent cellular cytotoxicity (ADCC) and is important for anti-tumor activities of many therapeutic antibodies. Bispecific antibody targeting natural killer (NK) cells has been studied for cancer therapy. In this work, anti-CD16a single-domain antibodies were identified from hCD16a immunized camel. Bispecific antibodies are then constructed by fusing these single domain antibodies with an anti-CEA single domain antibody. These bispecific antibodies can recruite NK cells to kill CEA-positive tumor cells, and inhibit tumor growth in vivo, suggesting that these anti-CD16a single domain antibodies are powerful tools to engaging NK cells for cancer therapy.

9.
Inflammation ; 2019 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-31664694

RESUMO

Periodontitis is a chronic infectious disease, the course and progression of which are determined by the interaction between microorganisms and the host. Interleukin 1ß plays an important role in the destruction of periodontal tissues. Interleukin 1 receptor antagonist (IL-1ra) can inhibit the biological activity of IL-1ß without triggering any intracellular signaling. This study aimed to prepare IL-1ra-loaded dextran/PLGA microspheres and evaluate the physical and chemical characteristics and anti-inflammatory properties. Results suggested that the microspheres can be easily prepared into a drug carrier with good biocompatibility and can effectively inhibit the gene expression of pro-inflammatory factors induced by IL-1ß in human gingival fibroblasts. Hence, the microspheres are excellent candidate for periodontitis treatment.

10.
Mol Med Rep ; 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31661120

RESUMO

Bone cancer pain (BCP) is a severe complication of advanced bone cancer. Although cannabinoid receptor 2 (CB2) agonists may have an analgesic effect, the underlying mechanism remains unclear. CB2 serves a protective role in various pathological states through the activation of autophagy. Therefore, the present study aimed to determine whether the analgesic effects of the selective CB2 agonist JWH015 was mediated by the activation of autophagy in BCP. BCP was induced by the intra­femur implantation of NCTC2472 fibrosarcoma cells in C3H/HeN mice. The pain behaviors were assessed on the following postoperative days. The selective CB2 agonist JWH015 (1 and 2 µg) was intrathecally administered on day 14 following implantation. AM630 (1 µg), a CB2 antagonist, was injected 30 min before JWH015 administration. Lipopolysaccharide (LPS; 100 nM)­stimulated primary neurons were treated with JWH015 (1 µM) and AM630 (1 µM) to further verify the mechanism by which CB2 affects autophagy. The results demonstrated that autophagy flux was impaired in spinal neurons during BCP, as indicated by the increased ratio of microtubule­associated protein 1 light chain 3ß (LC3B)­II/LC3B­I and increased expression of p62. Intrathecal administration of JWH015 attenuated BCP, which was accompanied by the amelioration of impaired autophagy flux (decreased LC3B­II/LC3B­I ratio and decreased p62expression). In addition, the activation of glia cells and upregulation of the glia­derived inflammatory mediators, interleukin (IL)­1ß and IL­6 were suppressed by JWH015. In LPS­stimulated primary neurons, IL­1ß and IL­6 were increased, and autophagy flux was impaired; whereas treatment with JWH015 decreased the expression of IL­1ß and IL­6, LC3B­II/LC3B­I ratio and expression of p62. These effects were by pretreatment with the CB2­selective antagonist AM630. The results of the present study suggested that the impairment of autophagy flux was induced by glia­derived inflammatory mediators in spinal neurons. Intrathecal administration of the selective CB2 agonist JWH015 ameliorated autophagy flux through the downregulation of IL­1ß and IL­6 and attenuated BCP.

11.
Reprod Biol Endocrinol ; 17(1): 82, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31651332

RESUMO

BACKGROUND: Obesity is a worldwide crisis impairing human health. In this condition, declines in sperm quality stem from reductions in sperm concentration, motility and increase in sperm deformity. The mechanism underlying these alterations remains largely unknown. This study, determined if obesity-associated proteomic expression patterns in mice sperm parallel those in spermatozoa obtained from obese humans. METHODS: An obese mouse model was established via feeding a high-fat diet (HFD). Histological analysis identified testicular morphology and a computer assisted semen analyzer (CASA) evaluated sperm parameters. Proteome analysis was performed using a label-free quantitative LC-MS/MS system. Western blot, immunohistochemical and immunofluorescent analyses characterized protein expression levels and localization in testis, sperm and clinical samples. RESULTS: Bodyweight gains on the HFD induced hepatic steatosis. Declines in sperm motility accompanied sperm deformity development. Differential proteomic analysis identified reduced cytoskeletal proteins, centrosome and spindle pole associated protein 1 (CSPP1) and Centrin 1 (CETN1), in sperm from obese mice. In normal weight mice, both CSPP1 and CETN1 were localized in the spermatocytes and spermatids. Their expression was appreciable in the post-acrosomal region parallel to the microtubule tracks of the manchette structure in spermatids, which affects spermatid head shaping and morphological maintenance. Moreover, CSPP1 was localized in the head-tail coupling apparatus of the mature sperm, while CETN1 expression was delimited to the post-acrosomal region within the sperm head. Importantly, sperm CSPP1 and CETN1 abundance in both the overweight and obese males decreased in comparison with that in normal weight men. CONCLUSION: These findings show that regionally distinct expression and localization of CETN1 and CSPP1 is strongly related to spermiogenesis and sperm morphology maintaining. Obesity is associated with declines in the CETN1 and CSPP1 abundance and compromise of both sperm morphology in mice and relevant clinical samples. This parallelism between altered protein expression in mice and humans suggests that these effects may contribute to poor sperm quality including increased deformity.

12.
Artigo em Inglês | MEDLINE | ID: mdl-31630797

RESUMO

Osteogenic differentiation of human bone marrow-derived mesenchymal stem cells (BMSCs) has been regarded as a central issue in fracture healing. MicroRNAs (miRNAs, miRs) participate in diverse physiological processes such as osteoblastic differentiation of BMSCs. In this study, we found that miR-664a-5p was upregulated during osteogenic differentiation of human BMSCs, and this upregulation positively correlated with the expression of osteogenic genes Runt-related transcription factor 2 (RUNX2), alkaline phosphatase (ALP), and osteocalcin (OCN). Overexpression of miR-664a-5p promoted the osteogenic differentiation of BMSCs, whereas a knockdown of miR-664a-5p suppressed it. Additionally, high-mobility group A2 (HMGA2) mRNA was identified as a direct target of miR-664a-5p that mediates the function of this miRNA. Overexpression of HMGA2 obviously attenuated miR-664a-5p-induced osteogenic differentiation of BMSCs. Thus, the newly identified miR-664a-5p-HMGA2 pathway expands our understanding of the mechanisms underlying the osteogenic differentiation of human BMSCs, may provide deeper insights into the regulation of this differentiation, and can point to new effective methods for treating osteoporosis.

13.
Org Lett ; 21(18): 7478-7483, 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31539926

RESUMO

We report a highly chemo- and diastereoselective [3 + 2] cyclization of vinylethylene carbonates and 5-alkenyl thiazolones through palladium catalysis. The previously inert aza-thioester moiety on the thiazolone substrates is reacted selectively with the zwitterionic π-allylpalladium species. A variety of amide monothioacetals (AMTA) with two quaternary stereocenters are facilely synthesized. An additional spirocyclic quaternary stereocenter could be further installed by Rh-catalyzed metal-carbene insertion into the C-S bond on the AMTA moiety in a highly stereoselective manner.

14.
Mol Med Rep ; 20(5): 4391-4392, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31485640

RESUMO

Subsequently to the publication of this article, the authors have realized that Fig. 4 contained some incorrectly incorporated data panels; specifically, the A­d, B­b and B­c panels did not display the correct data. The revised version of Fig. 4 featuring the correct data for the A­d, B­b and B­c panels is shown on the next page. Note that these errors did not affect the overall conclusions reported in the paper. The authors apologize to the Editor of Molecular Medicine Reports and to readership for any inconvenience caused. [the original article was published in Molecular Medicine Reports 16: 703­709, 2017; DOI: 10.3892/mmr.2017.6679].

15.
Org Lett ; 21(19): 7851-7856, 2019 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-31524412

RESUMO

A novel strategy of cascade radical C(sp2/sp3)-S bond cleavage and group-transfer cyclization is disclosed. Triggered by alkyl radicals, varieties of 2-isocyanoaryl thioethers containing aliphatic, aryl, and heteroaromatic groups can be cleaved and precisely reinstalled to give benzothiazole derivatives. Mechanistic studies reveal that the cascade reaction undertakes an intermolecular pathway, and the inner radical sources (R radicals) exhibit high priority over those of methyl radical origin from di-tert-butyl peroxide.

16.
Brain Behav Immun ; 82: 264-278, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31476414

RESUMO

Isorhynchophylline (IRN) has been demonstrated to have distinct anti-Alzheimer's disease (AD) activity in several animal models of AD. In this study, we aimed at evaluating the preventive effect of IRN on the cognitive deficits and amyloid pathology in TgCRND8 mice. Male TgCRND8 mice were administered with IRN (20 or 40 mg/kg) by oral gavage daily for 4 months, followed by assessing the spatial learning and memory functions with the Radial Arm Maze (RAM) test. Brain tissues were determined immunohistochemically or biochemically for changes in amyloid pathology, tau hyperphosphorylation and neuroinflammation. Our results revealed that IRN (40 mg/kg) significantly ameliorated cognitive deficits in TgCRND8 mice. In addition, IRN (40 mg/kg) markedly reduced the levels of Aß40, Aß42 and tumor necrosis factor (TNF-α), interleukin 6 (IL-6) and IL-1ß, and modulated the amyloid precursor protein (APP) processing and phosphorylation by altering the protein expressions of ß-site APP cleaving enzyme-1 (BACE-1), phosphorylated APP (Thr668), presenilin-1 (PS-1) and anterior pharynx-defective-1 (APH-1), as well as insulin degrading enzyme (IDE), a major Aß-degrading enzyme. IRN was also found to inhibit the phosphorylation of tau at the sites of Thr205 and Ser396. Immunofluorescence showed that IRN reduced the Aß deposition, and suppressed the activation of microglia (Iba-1) and astrocytes (GFAP) in the cerebral cortex and hippocampus of TgCRND8 mice. Furthermore, IRN was able to attenuate the ratios of p-c-Jun/c-Jun and p-JNK/JNK in the brains of TgCRND8 mice. IRN also showed marked inhibitory effect on JNK signaling pathway in the Aß-treated rat primary hippocampus neurons. We conclude that IRN improves cognitive impairment in TgCRND8 transgenic mice via reducing Aß generation and deposition, tau hyperphosphorylation and neuroinflammation through inhibiting the activation of JNK signaling pathway, and has good potential for further development into pharmacological treatment for AD.

17.
Artigo em Inglês | MEDLINE | ID: mdl-31561331

RESUMO

The mechanical properties of electrospun fiber meshes typically are measured by tensile testing at the macro-scale without precisely addressing the spatial scale of living cells and their submicron architecture. Atomic force microscopy (AFM) enables the examination of the nano- and micro-mechanical properties of the fibers with potential to correlate the structural mechanical properties across length scales with composition and functional behavior. In this study, a polyesteretherurethane (PEEU) polymer containing poly(p-dioxanone) (PPDO) and poly(ɛ-caprolactone) (PCL) segments was electrospun into fiber meshes or suspended single fibers. We employed AFM three point bending testing and AFM force mapping to measure the elastic modulus and stiffness of individual micro/nanofiber and fiber mesh. The local stiffness of fiber mesh including the randomized, intersecting structure was also examined for each individual fiber. Force mapping results with a set point of 50nN demonstrated the dependence of the elasticity of a single fiber on the fiber mesh architecture. The non-homogeneous stiffness along the same fiber was attributed to the intersecting structure of the supporting mesh morphology. The same fiber measured at a point with and without axial fiber support showed a remarkable difference in stiffness, ranging from 0.2 to 10 nN/nm respectively. For the region, where supporting fibers densely intersected, the stiffness was found to be considerably higher. In the region where the degrees of freedom of the fibers was not restricted, allowing greater displacement, the stiffness were observed to be lower. This study elucidates the relationship between architecture and the mechanical properties of a micro/nanofiber mesh. By providing a greater understanding of the role of spatial arrangement and organization on the surface mechanical properties of such materials, we hope to provide insight into the design of microenvironments capable of regulating cell functionality.

18.
Nanoscale ; 11(37): 17216-17221, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31531444

RESUMO

In the last few years, all-inorganic cesium lead halide (CsPbX3) quantum dots have shown unprecedented radical progress for practical applications in the optoelectronic field, but they quickly decompose when exposed to air. The in situ growth of the CsPbX3 particles inside amorphous glass can significantly improve their stability. Unfortunately, it is formidably difficult to precipitate whole-family CsPbX3 from a glass matrix and their photoluminescence quantum yields require further improvement. Herein, fluoride additives were introduced into oxyhalide borosilicate glasses to break the tight glass network, which promoted the nucleation/growth of CsPbX3 (X = Cl, Cl/Br, Br, Br/I and I) inside the glass. Importantly, the quantum efficiencies of glass-stabilized CsPbBr3, CsPb(Br/I)3 and CsPbI3 reached 80%, 60% and 50%, respectively, which are the highest efficiencies reported so far. Benefiting from the effective protection of robust glass, CsPbX3 quantum dots exhibited superior water resistance with more than 90% luminescence remaining after immersing them in water for 30 days, and halogen anion exchange among different CsPbX3 materials was completely inhibited. Two prototype light-emitting diodes were constructed by coupling green/red and green/orange/red quantum dots with InGaN blue chips, yielding bright white light with optimal luminous efficiency of 93 lm W-1, tunable color temperature of 2000-5800 K and high color rendering index of 90.

19.
Ecotoxicol Environ Saf ; 184: 109616, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31493588

RESUMO

The application of biogas slurry as an organic fertilizer is a promising method for utilizing breeding manure wastewater. At present, the impact of biogas slurry on the properties of organic matter in soil is not clear. In this study, a pot experiment in which chemical fertilizers were replaced with biogas slurry from a swine farm was performed. The fluorescence spectra combined with parallel factor (PARAFAC) analysis and principal component analysis (PCA) were used to explore the influence of biogas slurry on the protein and humic substance contents in the dissolved organic matter (DOM) in soil. The results showed that there were two proteins (component 3 (C3) and component 4 (C4)) and two humic substances ( component 1 (C1) and component 2 (C2)) in the DOM of the experimental soil. The application of swine biogas slurry can significantly increase the content of DOM in soil, but the increase was weakened with extended time. Compared with the CKA, the biogas slurry significantly increased the C1, C2, C3 and C4 contents in the initial stage by 116.17%, 76.41%, 578.71% and 278.13%, respectively. Within 28 days of planting corn, proteins with simple molecular structure in the DOM in the soil began to be transformed into humic substances with high molecular weight and more complex molecular structures. On the 60th day, the contents of C1 and C2 in the DOM of the treated treatments soil increased by 13.72%-34.40% and 5.05%-17.78% respectively, and tyrosine content decreased by 90.11%-94.41%. This study provides a new perspective on the effects of biogas slurry application on soil properties and sustainable utilization of soil.

20.
New Phytol ; 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31529514

RESUMO

Histone 3 Lysine 4 (H3K4) demethylation is ubiquitous in organisms, however the roles of H3K4 demethylase JARID1(Jar1)/KDM5 in fungal development and pathogenesis remain largely unexplored. Here, we demonstrate that Jar1/KDM5 in Botrytis cinerea, the grey mould fungus, plays a crucial role in these processes. The BcJAR1 gene was deleted and its roles in fungal development and pathogenesis were investigated using approaches including genetics, molecular/cell biology, pathogenicity and transcriptomic profiling. BcJar1 regulates H3K4me3 and both H3K4me2 and H3K4me3 methylation levels during vegetative and pathogenic development, respectively. Loss of BcJAR1 impairs conidiation, appressorium formation and stress adaptation; abolishes infection cushion (IC) formation and virulence, but promotes sclerotium production in the ΔBcjar1 mutants. BcJar1 controls reactive oxygen species (ROS) production and proper assembly of Sep4, a core septin protein and virulence determinant, to initiate infection structure (IFS) formation and host penetration. Exogenous cAMP partially restored the mutant appressorium, but not IC, formation. BcJar1 orchestrates global expression of genes for ROS production, stress response, carbohydrate transmembrane transport, secondary metabolites, etc., which may be required for conidiation, IFS formation, host penetration and virulence of the pathogen. Our work systematically elucidates BcJar1 functions and provides novel insights into Jar1/KDM5-mediated H3K4 demethylation in regulating fungal development and pathogenesis.

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