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1.
J Phys Condens Matter ; 32(8): 085702, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-31689691

RESUMO

The analytical bond-order potential has been developed for simulating fission product (Ag, Pd, Ru, and I) behavior in SiC, especially for their diffusion. We have proposed adding experimentally available elastic constants and physical properties of the elements as well as important defect formation energies calculated from density functional theory simulation to the list of typical properties as the extensive fitting database. The results from molecular dynamics simulations are in a reasonable agreement with defect properties and energy barriers of their experimental/computational counterparts. The successful validation of the new potential has established a good reliability and transferability of the potentials, which enables the ability of simulation in extended scale. The kinetic behavior such as diffusion of different interstitials is then realized by applying the new interatomic potentials. The bulk diffusion is less likely to dominate the transport of the four fission products under pure thermal condition, when we refer to their extremely small values of the effective diffusion coefficients. The interstitial mechanism is hard for Pd, Ru, and I to access due to the high formation energy and high migration energy. However, it is found that the migration energy of silver is relatively low, which indicates Ag diffusion via an interstitial mechanism being feasible, especially under irradiation condition, where massive interstitials can be formed in high-temperature nuclear reactors.

2.
Artigo em Inglês | MEDLINE | ID: mdl-31711664

RESUMO

At present, although a large number of palladium-based nanowire electrocatalysts have been prepared, there are few reports on nanowires containing rich metal oxides. Herein, porous PdCu alloy nanowires and PdCu-SnO2 nanowires were prepared by using a galvanic displacement synthesis method. Due to their one-dimensional structure, rough surfaces with non-homogeneous edges, electronic effect, and the advanced PdCu/SnO2 interface of the as-synthesized PdCu-SnO2 nanowire catalysts, they exhibited a mass activity of 7770.0 mA mg-1 towards ethanol oxidation, which was 7.6-fold higher than that of Pd/C catalysts (1025.0 mA mg-1). In addition, they behaved strong durability upon chronoamperometry and continuous cyclic voltammetry tests. The electrochemical measurements demonstrated that SnO2 was introduced into the PdCu/SnO2 interface, which promoted the oxidation of ethanol at a lower potential and accelerated the oxidation of Pd-COads via SnO2-OHads to regenerate the active sites. This research highlights the significance of introducing metal oxides into the nanostructure interface, and the performance of Pd-containing catalysts towards ethanol oxidation reaction was greatly improved.

3.
Front Immunol ; 10: 2424, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31708914

RESUMO

Zika virus (ZIKV) specific neutralizing antibodies hold great promise for antibody-based interventions and vaccine design against ZIKV infection. However, their development in infected patients remains unclear. Here, we applied next-generation sequencing (NGS) to probe the dynamic development of a potent and protective ZIKV E DIII-specific antibody ZK2B10 isolated from a ZIKV convalescent individual. The unbiased repertoire analysis showed dramatic changes in the usage of antibody variable region germline genes. However, lineage tracing of ZK2B10 revealed limited somatic hypermutation and transient expansion during the 12 months following the onset of symptoms. The NGS-derived, germline-like ZK2B10 somatic variants neutralized ZIKV potently and protected mice from lethal challenge of ZIKV without detectable cross-reactivity with Dengue virus (DENV). Site-directed mutagenesis identified two residues within the λ chain, N31 and S91, that are essential to the functional maturation of ZK2B10. The repertoire and lineage features unveiled here will help elucidate the developmental process and protective potential of E DIII-directed antibodies against ZIKV infection.

4.
Artigo em Inglês | MEDLINE | ID: mdl-31753507

RESUMO

The development of high-performance catalysts is of great importance in direct alcohol fuel cells. One dimensional nanorods catalysts are hopeful candidates as efficient alcohol electrocatalysis. However, it is desirable to precisely modulate the surface morphology of one dimensional nanorods nanocrystals to acquire better catalytic property. We effectively integrate properties of robust one dimensional nanorods, core@shell structure, and ternary nanoalloy into a new PtNiPd@Pt core@shell nanorods with high density bumps on the surface for potential better catalytic behaviors. Notably, those unique structures make the PtNiPd@Pt nanocrystals display favorable electrocatalytic performance towards methanol oxidation reaction. Specifically, the composition-optimized PtNi0.20Pd0.52 nanorods exhibit the highest methanol oxidation reaction specific activity of 18.01 mA cm-2 among PtNiPd@Pt catalysts in alkaline condition. The specific activity is 8.5 times higher than that of Pt/C catalysts. Moreover, electrochemical stability measurements also confirm the better reaction endurance of PtNi0.20Pd0.52 nanorods. Our work provides a reference to well tune the fine surface structure on one dimensional nanorods catalysts in the direction of superior electrocatalytic behaviors.

5.
Urology ; 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31734348

RESUMO

OBJECTIVE: To assess and analyze the contemporary causes of inhospital deaths of spina bifida patients. METHODS: It was a cross-sectional observational study of the longitudinal national cohort of all patients hospitalized in French public and private hospitals. We analyzed the data from the French hospital discharge database (Programme de Médicalisation des Systemes d'Information, PMSI) from 2009 to 2014. The number of inhospital deaths was extracted using the combination of the ICD-10 codes "Q05" or "Q760" and a discharge code=9. RESULTS: There were 138 inhospital deaths of spina bifida patients over the 6-year study period. The median age at death was 41 years (IQR: 25-52). The median age at death was significantly lower in patients with vs. without hydrocephalus (26.6 vs. 45.5 years; p<0.0001). The leading cause of inhospital death was urological disorders (n=24; 17.3%). Other main causes of death were pulmonary disorders (n=23; 16.7%), neurological disorders (n=19; 13.8%) and bowel disorders (n=15; 10.9%). Upper urinary tract damage accounted for most of the urological causes of death: eight patients died from urinary tract infections (33.3%), seven patients died from renal failure (29.2%), four died from bladder cancer (16.7%) and five from other urological causes. The only variable significantly associated with a death from urological causes was the absence of hydrocephalus (OR=0.26; p=0.009). CONCLUSION: Urological disorders remain the leading cause of inhospital death in spina bifida patients in France. The present study highlights that efforts to improve the urological management of the spina bifida population are still greatly needed.

6.
J Nutr Biochem ; 74: 108246, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31671360

RESUMO

The risk of overweight or obesity in association with early exposure of antibiotics remains an important public issue for health-care of children. Low-dose antibiotics (LDA) have been widely used to enhance growth rate of pigs, providing a good animal model to study the underlying mechanism. In present study, 28 female piglets, weaned at 21 d, were randomly classified into two groups, receiving either a control diet or a diet supplemented with LDA for 4 weeks. The total bacterial load and intestinal microbiota were determined by qPCR and 16S rRNA amplicon sequencing. UPLC-QTRAP-MS/MS and RNA-seq were further used to determine the colonic SCFAs and transcriptomes. Results showed that LDA significantly increased growth rate and food intake. The F/B index, Methanosphaera species, and the pathway of "carbohydrate metabolism" were improved by LDA exposure, indicating the better carbohydrate degradation and energy utilization. Furthermore, correlation analysis indicated the microbial community contributing to SCFAs production was enriched upon LDA exposure, associating with increased concentrations of short-chain and branched-chain fatty acids (caproate, 2-methyl butyrate and 4-methyl valerate). A multivariate linear fitting model analysis highlighted that caproate was positively correlated with two genera (Faecalibacterium and Allisonella) and four differentially expressed genes (ZNF134, TBX5, NEU4 and SEMA6D), which were all significantly increased upon LDA exposure. Collectively, our study indicates that the growth-promoting effect of LDA exposure in early life is associated with the shifts of colonic microbiota to increase utilization of carbohydrates and energy, enhanced SCFAs production and colonic functions.

7.
Environ Pollut ; : 113540, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31708278

RESUMO

In plants, excess selenium (Se) causes toxicity, while the beneficial effects of nitric oxide (NO) have verified in plants under various abiotic conditions. In order to ensure safely Se-enriched rice production, the objective of the research was to clarify how exogenous NO alleviated high Se toxicity in rice. Under high Se (25 µM) stress, the effects of exogenous NO (by applying sodium nitroprusside, an exogenous NO donor) on growth parameters, Se content, Se speciation, photosynthesis, antioxidant system, expressions of Se transport and metabolism-related genes (phosphate transporter, OsPT2; S-adenosylmethionine synthase 1, OsSAMS1; cysteine synthase, OsCS; Se-binding protein gene, OsSBP1) in rice seedlings were investigated by a hydroponic experiment. The results showed that exogenous NO alleviated high Se-induced irreversible damage to root morphology, growth, photosynthesis, antioxidant capacity and decreased the contents of MDA, H2O2 and proline significantly in rice seedlings. Compared with high Se treatment, application of exogenous NO reduced root Se content (10%), and the Se(VI) decreased by 100% in root and shoot. Besides, exogenous NO decreased the accumulation of inorganic Se speciation in rice roots and shoots. Also, the qRT-PCR analysis showed that down-regulated gene expressions of OsPT2, OsSAMS1 and OsCS affected significantly via exogenous NO. So, the exogenous NO could effectively decrease the toxicity of high Se treatment in rice.

8.
Neuroscience ; 424: 1-11, 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31734415

RESUMO

The administration of glucocorticoids (GCs) for the treatment of traumatic brain injury (TBI) is controversial. Both protective and deleterious effects of GCs on the brain have been reported in previous studies, while the mechanisms are unclear. Most experimental studies have reported glucocorticoid receptor (GR)-mediated deleterious effects after TBI. Sufficient mineralocorticoid receptor (MR) activation was reported to be indispensable for normal function and survival of hippocampal neurons, but changes in MR expression and activation and the roles of MRs in the survival of neurons after TBI remain unclear. We hypothesized that inadequate MR expression and activation caused by TBI aggravates posttraumatic hippocampal apoptosis but that restoration by restoring MRs promotes the survival of neurons. Using a rat controlled cortical impact model, we examined plasma corticosterone, MR expression and activation, neuronal apoptosis in the hippocampus, and spatial memory on day 3 after injury with and without fludrocortisone (1 mg/kg) treatment. Plasma corticosterone levels were significantly reduced after TBI. In addition, both MR expression and activation were inhibited. Fludrocortisone treatment significantly increased both the expression and activation of MRs, reduced the number of apoptotic neurons and cell loss in the ipsilateral hippocampus, and subsequently improved spatial memory. Its protective effects were counteracted by the MR antagonist spironolactone. The results suggest that adequate expression and activation of MRs is crucial for the survival of neurons after TBI and that fludrocortisone protects hippocampal neurons via promoting MR expression and activation.

9.
Ocul Immunol Inflamm ; : 1-6, 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31743043

RESUMO

Purpose: To assess the characteristics of parafoveal microvascular abnormalities in Behcet's uveitis (BDU) using projection-resolved optical coherence tomographic angiography (PR-OCTA).Methods: A retrospective study of BDU patients who underwent PR-OCTA examination between April 1, 2017 and October 31, 2018.Results: Sixty consecutive BDU patients (102 eyes) were included. Sixty-two (124 eyes) healthy subjects served as normal controls (NCs). As compared with NCs, the vessel densities (VDs) of superficial and deep retinal capillary plexuses were decreased, and the fovea avascular zone area, perimeter and acircularity index were increased in BDU eyes (all p < .001). Macular edema (p < .001) and long uveitis course (p = .033) were identified as risk factors for capillary disruptions. Consistent VD reductions were observed in the quiescent fellow eyes of BDU patients during unilateral uveitis relapse.Conclusions: BDU patients had significant OCTA changes. Macular circulatory disturbances may exist in the quiescent fellow eyes during unilateral BDU attack.

10.
J Cell Biochem ; 2019 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-31680314

RESUMO

Circ-Foxo3 is a circRNA encoded by the human FOXO3 gene and works as a sponge for potential microRNAs (miRNAs) to regulate cancer progression. However, the role of circ-Foxo3 in esophageal squamous cell cancer (ESCC) is not clear. In this study, circ-Foxo3 was lowly expressed in cell lines and ESCC tissues. Meanwhile, overexpression of circ-Foxo3 inhibited cell growth, migration, and invasion, whether in vivo or in vitro. Mechanically, we found a potential miRNA target, miR-23a, which negatively correlated with circ-Foxo3 in ESCC. Then, a luciferase assay confirmed the relationship between the circ-Foxo3 and miRNA. Moreover, circ-Foxo3 upregulation of PTEN occurred through "sponging" miR-23a. Taken together, these results indicated that the circ-Foxo3/miR-23a/PTEN pathway was critical for inhibiting the ESCC progression. This may provide a promising target for treat ESCC.

11.
Appl Opt ; 58(27): 7643-7648, 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31674421

RESUMO

The feasibility of an overwater light-sheet Scheimpflug lidar system for underwater three-dimensional (3D) profiling is considered. Corrections for the refraction at the air-water interface are proposed. Applications for profiling marine ecosystems are explored in distance up to several meters, and millimeter precision is accomplished. The experimental results demonstrate that our system is suitable for underwater 3D profiling and has great potential in marine biological detection.

12.
Artigo em Inglês | MEDLINE | ID: mdl-31752060

RESUMO

Trichoderma reesei is the major filamentous fungus used to produce cellulase and there are huge interests in promoting its ability to produce higher titers of cellulase. Among the many factors affecting cellulase production in T. reesei, the mycelial phenotype is important but seldom studied. Herein, a close homolog of the Neurospora crassa COT1 kinase was discovered in T. reesei and designated TrCOT1, which is of 83.3% amino acid sequence identity. Functional disruption of Trcot1 in T. reesei by RNAi-mediated gene silencing resulted into retarded sporulation on PDA and dwarfed colonies on MM agar plates containing glucose, xylan, lactose, xylose, or glycerol as the sole carbon source. The representative mutant strain, SUS2/Trcot1i, also displayed reduced mycelia accumulation but hyperbranching in the MM glucose liquid medium, with Lhgu values decreased to 73.0 µm/tip compared to 239.8 µm/tip for the parent strain SUS2. The hyperbranching phenotype led to slightly but significantly increased cellulase secretion from 24 to 72 h in a batch culture. However, the cellulase production per unit of mycelial biomass was much more profoundly improved from 24 to 96 h.

14.
ACS Appl Mater Interfaces ; 11(47): 44333-44341, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31692328

RESUMO

Owing to their low cost and abundant reserves relative to conventional lithium-ion batteries (LIBs), potassium-ion batteries (PIBs), and aluminum-ion batteries (AIBs) have shown appealing potential for electrochemical energy storage, but progress so far has been limited by the lack of suitable electrode materials. In this work, we demonstrated a facile strategy to achieve highly reversible potassium and aluminum ions storage in strongly coupled nanosized MoSe2@carbon matrix, induced through an ion complexation strategy. We present a broad range of electrochemical characterization of the synthesized product that exhibits high specific capacities, good rate capability, and excellent cycling stability toward PIBs and AIBs. Through a series of systematic ex situ X-ray photoelectron spectroscopy (XPS) characterizations and density functional theory (DFT) calculations, the Al3+ intercalation mechanism of MoSe2-based AIBs are elucidated. Moreover, both the assembled PIBs and AIBs worked well when exposed to low and high temperatures within the range of -10 to 50 °C, showing promise for energy storage devices in harsh environment. The present study provides new insights into the exploration of MoSe2 as high-performance electrode materials for PIBs and AIBs.

15.
Antiviral Res ; 173: 104652, 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31751590

RESUMO

Both classical swine fever (CSF) and pseudorabies are highly contagious, economically significant diseases of swine in China. Although vaccination with the C-strain against classical swine fever virus (CSFV) is widely carried out and severe outbreaks of CSF seldom occur in China, CSF is sporadic in many pig herds and novel sub-subgenotypes of CSFV endlessly emerge. Thus, new measures are needed to eradicate CSFV from Chinese farms. The emergence of a pseudorabies virus (PRV) variant also posed a new challenge for the control of swine pseudorabies. Here, the recombinant PRV strain JS-2012-ΔgE/gI-E2 expressing E2 protein of CSFV was developed by inserting the E2 expression cassette into the intergenic region between the gG and gD genes of the gE/gI-deletion PRV variant strain JS-2012-ΔgE/gI. The recombinant virus was stable when passaged in vitro. A single vaccination of JS-2012-ΔgE/gI-E2 via intramuscular injection fully protected against lethal challenges of PRV and CSFV. Vaccination of piglets with the recombinant JS-2012-ΔgE/gI-E2 in the presence of high levels of maternally derived antibodies (Abs) to PRV can provide partial protection against lethal challenge of CSFV. Vaccination of the recombinant PRV JS-2012-ΔgE/gI-E2 strain did not induce the production of Abs to the gE protein of PRV or to the CSFV proteins other than E2. Thus, JS-2012-ΔgE/gI-E2 appears to be a promising recombinant marker vaccine candidate against PRV and CSFV for the control and eradication of the PRV variant and CSFV.

16.
Nat Commun ; 10(1): 5338, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31767845

RESUMO

Many platinum group metal-free inorganic catalysts have demonstrated high intrinsic activity for diverse important electrode reactions, but their practical use often suffers from undesirable structural degradation and hence poor stability, especially in acidic media. We report here an alkali-heating synthesis to achieve phase-mixed cobalt diselenide material with nearly homogeneous distribution of cubic and orthorhombic phases. Using water electroreduction as a model reaction, we observe that the phase-mixed cobalt diselenide reaches the current density of 10 milliamperes per square centimeter at overpotential of mere 124 millivolts in acidic electrolyte. The catalyst shows no sign of deactivation after more than 400 h of continuous operation and the polarization curve is well retained after 50,000 potential cycles. Experimental and computational investigations uncover a boosted covalency between Co and Se atoms resulting from the phase mixture, which substantially enhances the lattice robustness and thereby the material stability. The findings provide promising design strategy for long-lived catalysts in acid through crystal phase engineering.

17.
Plant Cell ; 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31776233

RESUMO

Iron (Fe) is an essential micronutrient for plant growth and development. Any defects in the maintenance of Fe homeostasis will alter plant productivity and the quality of their derived products. In Arabidopsis thaliana, the ILR3 transcription factor plays a central role in the control of Fe homeostasis. In this study, bHLH121 was identified as an ILR3 interacting transcription factor. Interaction studies showed that bHLH121 interacts also with the three closest homologues of ILR3 (i.e. bHLH34, bHLH104 and bHLH115). bhlh121 loss-of-function mutants display severe Fe homeostasis defects that could be reverted by exogenous Fe supply. bHLH121 acts as a direct transcriptional activator of key genes involved in the Fe regulatory network, including bHLH38, bHLH39, bHLH100, bHLH101, PYE, BTS, BTSL1 as well as IMA1 and IMA2. In addition, bHLH121 is necessary for the activation of FIT expression in response to Fe deficiency via an indirect mechanism. bHLH121 is expressed throughout the whole plant body and its expression is not affected by Fe availability. In contrast, Fe availability conditions the cellular localization of bHLH121 protein in roots. Altogether these data show that bHLH121 is a master regulator of Fe homeostasis that acts upstream from FIT in concert with ILR3 and its closest homologues.

18.
Sci China Life Sci ; 62(10): 1396-1399, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31573054
20.
Biol Reprod ; 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31621828

RESUMO

The placenta, which originates from the trophectoderm (TE), is the first organ to form during mammalian embryogenesis. Recent studies based on bioinformatics analysis have revealed that heterogeneous gene expressioninitiates cell-fate decisions and directs two distinct cell fates by modulating the balance of pluripotency and differentiation as early as the four-cell stage. However, direct developmental evidence to support this is still lacking. To address at which stage the cell fate of the TE and inner cell mass (ICM) is determined, in this study, we administered a microinjection of Cre mRNA into a single blastomere of the mTmG mouse at different cleavage stages before implantation to examine the distributions of the descendants of the single-labeled cell in the mouse fetus and the placenta at E12.5. We found that the descendants of the labeled cells at the two-cell stage contributed to both the placenta and the fetus. Notably, the derivatives of the labeled cells at the four-cell stage fell into three categories: (1) distributed in both embryonic and extraembryonic lineages; (2) distributed only in mouse placental trophoblast layers; or (3) distributed only in the lineage derived from the inner cell mass (ICM). In addition, these results fell in line with single-cell studies focusing on gene expression patterns that characterize particular lineages within the blastocyst. In conclusion, this study shows that the four-cell blastomeres differ in their individual developmental properties insofar as they contribute to either or both the ICM and trophoblast fate.

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