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1.
J Med Virol ; 92(1): 34-44, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31429942

RESUMO

Mounting evidence indicates that serum soluble E-cadherin (sE-cadherin) serves as an important player in various physiological and pathological processes. However, the crosstalk between serum sE-cadherin and oxidative stress in chronic hepatitis B (CHB) remains to be illustrated. The main purpose of this study is to explore the molecular mechanisms underlying the function of sE-cadherin in CHB virus infection. Levels of serum sE-cadherin, total antioxidant capacity (TAC), glutathione (GSH), superoxide dismutase (SOD), total oxidant activity (TOA), NADPH oxidase 2 (NOX2), and malondialdehyde (MDA), from 51 patients with hepatitis B envelope antigen (HBeAg)-negative CHB, 54 patients with HBeAg-positive CHB, and 109 healthy individuals were detected by enzyme-linked immunosorbent assay. In our study, patients with CHB showed significantly higher serum sE-cadherin levels than healthy individuals (P < .01). Furthermore, we also found that the serum sE-cadherin levels were significantly negatively correlated with TAC, antioxidant enzymes (GSH and SOD) in patients with CHB, and that serum sE-cadherin concentrations were significantly positively correlated with liver enzyme markers (alanine transaminase and aspartate aminotransferase) and oxidative markers (TOA, NOX2, and MDA) in patients with CHB. Therefore, serum sE-cadherin may act as a new candidate biomarker for reflecting inflammation and oxidative stress status in the development and progression of hepatitis B virus infection.

2.
J Phys Condens Matter ; 32(6): 065002, 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-31648212

RESUMO

Electroluminescence devices based on all-inorganic halide perovskite material with excellent luminescence performance have been studied extensively in recent years. However, the important role for the electrodes of electroluminescence devices is payed few attention by theoretical and experimental studies. Appropriate electrodes can reduce the Schottky barrier height to decrease the energy loss, and prevent the metal impurities from diffusing into the perovskite material to generate deep traps levels, which improves the luminous efficiency and lifetime of devices. In this paper, not only the interface effects between CsPbBr3 and common metal electrode (Ag, Au, Ni, Cu and Pt) are studied by first-principle calculations, but also the diffusion effects of metal electrode atom into the CsPbBr3 layer are also explored by nudged elastic band calculations. The calculated results show the metal Ag is more suitable for the cathode for CsPbBr3 electroluminescence devices, while the metal Pt is more applicable for the anode. Based on the overall consideration about the interface effects and diffusion effects of the CsPbBr3-metal electrode junctions, the essential principle is analyzed. The work provides theoretical guidance for how to select the right electrode for the electroluminescence performance of all-inorganic halide perovskite. The critical factor of Schottky barrier height between the electrode and the light-emitting semiconductor, and transition level generated by metal impurities also provide a valuable reference how to select the suitable electrodes for other electroluminescence devices.

3.
J Phys Condens Matter ; 32(6): 065004, 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-31470426

RESUMO

Recently, the traditional infrared photodetectors (PDs) shows limited application in various areas, due to the narrow band-gap, high cost and even complex manufacturing process. In this situation, scientist have paid much attention to achieve the ultra broadband PDs from the deep ultraviolet to the near infrared. The energy band engineering for two-dimensional (2D) van der Waals heterojunction with free chemical dangling bonds is an effective method to fabricate High-performance Photodetectors. In this work, we employ density functional calculation to construct a type-II CdTe/MoS2 heterostructure and calculate its electronic properties. The results reveal that the CdTe/MoS2 has the narrow band gap of 0.64 eV and electrons transfer from the CdTe to MoS2 layer, which promotes the separation of photogenerated carriers and enhance the photoelectron conversion efficiency. Driven by the smaller band gap, it can respond to near infrared, visible and ultraviolet light, demonstrating it the promising application for solar cell. Furthermore, the analysis of molecules adsorption and band edge alignment indicates that the CdTe/MoS2 is prone to capture H2O and release the H2 molecules, which is conductive to the photocatalytic water splitting for hydrogen generation. Our work suggests that the CdTe/MoS2 heterostructure is a potential candidate as a solar cell and even photocatalyst, and also provides a new sight for experimental and theoretical research to design a highly efficient device.

4.
Opt Express ; 27(20): 28104-28113, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31684568

RESUMO

A compact and high sensitivity refractive index (RI) sensor has been theoretically and experimentally demonstrated based on dual-mode interferometer (DMI) in an eccentric core few-mode fiber (ECFMF). The DMI is fabricated by fusion splicing a piece of ECFMF etched by hydrofluoric acid (HF) and two single mode fibers (SMFs) with a lateral-offset. The interference is formed by LP01 and LP11 modes in the eccentric core of ECFMF. The etched ECFMF-DMI based on core-core mode interference exhibits a higher RI sensitivity than the DMI based on core-cladding mode interference. The sensitivity reaches up to 2565.2 nm/RIU around the RI of 1.4. Both of the etched and unetched ECFMF-DMIs have low temperature sensitivities of 9.6 pm/°C and 33.1 pm/°C, respectively. The etched ECFMF-DMI based on the core-core mode interference possesses tremendous superiority for RI measurement due to its high RI sensitivity and low temperature cross, therefore the proposed sensor has great potentials in chemical and biological fields.

5.
J Clin Immunol ; 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31686315

RESUMO

PURPOSE: Signal transducer and activator of transcription 1 (STAT1) is a transcription factor that mediates cellular responses to interferons (IFNs) and other cytokines and growth factors in diverse cell types. STAT1 gain-of-function (GOF) mutations result in an unexpectedly wide range of clinical features. It remains unclear why STAT1 GOF mutations result in such a broad spectrum of phenotypes. METHODS: We analyzed the clinical, molecular, and phenotypic characteristics of nine Chinese patients with STAT1 GOF mutations. RESULTS: This study enrolled nine patients with STAT1 GOF mutations including five novel mutations. We discuss the molecular and phenotypic characterization such as unique Penicillium marneffei lymphadenitis. Patients with STAT1 GOF mutations had defects in both innate and adaptive immunity, including impaired T cell receptor (TCR) diversity; reduced numbers of naïve and effector memory CD4+ T cells, memory B cells, and NK cells; and defects in the production of IL-17A and IFN-γ. In addition, experiments with primary immune cells revealed that enhanced STAT1 phosphorylation resulted from not only lower rates of STAT1 dephosphorylation but also increased total STAT1 expression. CONCLUSIONS: Our report provides the first comprehensive overview of the molecular genetics, clinical heterogeneity, and underlying immunological abnormalities of patients with STAT1 GOF mutations in China. In further study, to find the relationship between different STAT1 GOF mutations and clinical phenotype as well as the mechanism of increased total STAT1 expression will be needed.

6.
Artigo em Inglês | MEDLINE | ID: mdl-31713966

RESUMO

Lithium-sulfur (Li-S) batteries are well known as one of the most promising next-generation batteries owing to its ultra-high theoretical energy density and abundant sulfur resources. During the past 20 years, various sulfur materials have been reported. As the representative of molecular scale sulfur composite cathode, sulfurized pyrolyzed poly(acrylonitrile) (S@pPAN) exhibits several competitive advantages in terms of electrochemical behaviors. Currently, S@pPAN attracts increasing attentions although it was first reported in 2002. In this review, we firstly summarize its molecular model, which benefits to elucidate the correlation between structure property and exceptional electrochemical performance. Secondly, we classify the modification strategies into three parts, including material improvement, binder and electrolyte screening. In consideration of promising future of S@pPAN, several research and development directions are also suggested.

7.
Microb Pathog ; 138: 103794, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31672528

RESUMO

BACKGROUND: Necrotizing enterocolitis (NEC) is a major cause of morbidity and mortality in premature infants. In order to evaluate the efficacy of probiotics in the prevention of stage II-III NEC, we performed a meta-analysis of clinical studies. METHODS: We searched in PubMed, Medline and Embase from 1 January 1990 to 16 January 2018. Heterogeneity was examined by Q-test. Publication bias was evaluated by funnel plot and Egger's regression test. RESULTS: 30 articles were identified meeting the inclusion criteria. Data showed that probiotics supplement could significantly reduce the risk of stage II-III NEC (RR = 0.51, 95% CI, 0.38 to 0.67, P < 0.001) and death rate (RR = 0.69, 95% CI, 0.55 to 0.87, P = 0.002). The mixed probiotics and lactobacillus could reduce the risk of stage II-III NEC (for mixed probiotics, RR = 0.39, 95% CI, 0.26 to 0.57; for lactobacillus, RR = 0.53, 95% CI, 0.36 to 0.78), while bifidobacterium or saccharomyces did not have such effect. The results also indicated that only the mixed probiotics could reduce the risk of deaths (RR = 0.52, 95%CI, 0.34 to 0.80). Subgroup analysis for mortality revealed that probiotics had significant effect in Asian region (RR = 0.54, 95% CI, 0.37 to 0.80, P = 0.002) but not in non-Asian region (RR = 0.84, 95% CI, 0.66 to 1.08, P = 0.179). CONCLUSIONS: Probiotics could significantly decrease the risk of stage II-III NEC and death. Compared to using single probiotics species, the application of combining different probiotics has a better efficacy in the prevention of stage II-III NEC and death, especially in the Asian population.

8.
J Chemother ; : 1-11, 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31724495

RESUMO

We assessed the expression of Serpin Family E Member 1 (SERPINE1) and its prognostic values in gastric adenocarcinoma (GAC) by using the data from TCGA database. The biological functions of SERPINE1 in GAC cells were detected by cell counting Kit-8, colony-forming, Transwell, and wound-healing assays, appropriately. Relative mRNA and protein levels were detected by RT-qPCR and western blot. Bioinformatics analysis indicated that SERPINE1 was significantly up-regulated in GAC tissues compared to normal tissues. High SERPINE1 expression led to a short overall survival and could act as an independent prognosticator for GAC patients. Besides, down-regulation of SERPINE1 showed a suppressive effect on the phenotype of GAC cells and significantly inhibited the EMT process. Over-expression of SERPINE1 got the reverse outcomes. These data suggest that SERPINE1 contributes to the proliferation, invasion and migration of GAC cells, insinuating that SERPINE1 may be considered as a novel biomarker for GAC treatment.

9.
Lipids ; 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31691988

RESUMO

In the brain, approximately 90% of oxylipins are esterified to lipids. However, the significance of this esterification process is not known. In the present study, we (1) validated an aminopropyl solid phase extraction (SPE) method for separating esterified lipids using 100 and 500 mg columns and (2) applied the method to quantify the distribution of esterified oxylipins within phospholipids (PL) and neutral lipids (NL) (i.e. triacylglycerol and cholesteryl ester) in rats subjected to head-focused microwave fixation (controls) or CO2 -induced hypercapnia/ischemia. We hypothesized that oxylipin esterification into these lipid pools will be altered following CO2 -induced hypercapnia/ischemia. Lipids were extracted from control (n = 8) and CO2 -asphyxiated (n = 8) rat brains and separated on aminopropyl cartridges to yield PL and NL. The separated lipid fractions were hydrolyzed, purified with hydrophobic-lipophilic-balanced SPE columns, and analyzed with ultra-high-pressure liquid chromatography coupled to tandem mass spectrometry. Method validation showed that the 500 mg (vs 100 mg) aminopropyl columns yielded acceptable separation and recovery of esterified fatty acid epoxides but not other oxylipins. Two epoxides of arachidonic acid (ARA) were significantly increased, and three epoxides of docosahexaenoic acid (DHA) were significantly decreased in brain NL of CO2 -asphyxiated rats compared to controls subjected to head-focused microwave fixation. PL-bound fatty acid epoxides were highly variable and did not differ significantly between the groups. This study demonstrates that hypercapnia/ischemia alters the concentration of ARA and DHA epoxides within NL, reflecting an active turnover process regulating brain fatty acid epoxide concentrations.

10.
Blood ; 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31697823

RESUMO

To study the mechanisms of relapse in acute lymphoblastic leukemia (ALL), we performed whole-genome sequencing of 103 diagnosis-relapse-germline trios and ultra-deep sequencing of 208 serial samples in 16 patients. Relapse-specific somatic alterations were enriched in 12 genes (NR3C1, NR3C2, TP53, NT5C2, FPGS, CREBBP, MSH2, MSH6, PMS2, WHSC1, PRPS1, and PRPS2) involved in drug response. Their prevalence was 17% in very early relapse (<9 months from diagnosis), 65% in early relapse (9-36 months), and 32% in late relapse (>36 months) groups. Convergent evolution, where multiple subclones harbor mutations in the same drug resistance gene, was observed in six relapses and confirmed by single-cell sequencing in one case. Mathematical modeling and mutational signature analysis indicated that early relapse resistance acquisition was frequently two-step process where a persistent clone survived initial therapy, and later acquired bona fide resistance mutations during therapy. In contrast, very early relapses arose from pre-existing resistant clone(s). Two novel relapse-specific mutational signatures, one of which was caused by thiopurine treatment based on in vitro drug exposure experiments, were identified in early and late relapses but were absent from 2,540 pan-cancer diagnosis samples and 129 non-ALL relapses. The novel signatures were detected in 27% of relapsed ALLs and were responsible for 46% of acquired resistance mutations in NT5C2, PRPS1, NR3C1, and TP53. These results suggest that chemotherapy-induced drug resistance mutations facilitate a subset of pediatric ALL relapses.

11.
Math Biosci Eng ; 16(6): 7659-7670, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31698632

RESUMO

Objectives: The purpose of this meta-analysis was to evaluate the efficacy and toxicity profile of apatinib for the treatment of advanced non-small cell lung cancer (NSCLC). Methods: We systematically searched databases for randomized clinical trials published as of November 25, 2017, in which apatinib treatment was compared to placebo or chemotherapy in patients with advanced NSCLC. Two investigators independently assessed the articles and extracted their data. The hazard ratios (HRs) for progression-free survival (PFS), relative risks (RRs) for overall response rates (ORRs), disease control rates (DCRs), and odds ratios (ORs) for main toxicity were analyzed using the RevMan 5.3 software (Copenhagen: The Nordic Cochrane Centre, The Cochrane Collaboration, 2014). Results: Our analysis included 413 patients from 5 clinical studies. The pooled HR for PFS was 0.32 (95% confidence interval (CI) 0.21-0.48; P < 0.00001). The pooled RRs for ORR and DCR were 2.03 (95% CI 1.36-3.01; P = 0.0005) and 1.66 (95% CI 1.07-2.57; P = 0.02), respectively. The pooled OR for main toxicity was 1.34 (95% CI, 0.57-3.17; P = 0.5). Conclusions: Apatinib was a viable treatment alternative for advanced NSCLC, as it offered a clinically meaningful and statistically significant improvement in PFS, ORR, and DCR. Moreover, therapy with apatinib did not significantly increase toxicity.

12.
Int Immunopharmacol ; : 105980, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31699670

RESUMO

Over-activation of microglia disrupts the physiological homeostasis of the brain, and induces inflammatory response and other processes which are implicated in neurodegenerative diseases. Therefore, theoretically, suppression of neuroinflammation would slow the progression of neurodegenerative disease. In this study, we investigated the possible protective effects of Ferulic acid (FA) against benzo(a)pyrene (BaP)-induced microglial activation using BV2 cells as the model system. Exposure of BV2 cells to BaP (10 µM) significantly increased DNA damage and the production of pro-inflammatory mediators, including nitric oxide (NO), inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), reactive oxygen species (ROS), malondialdehyde (MDA), and cytokines (interleukins-1ß and -6). On the other hand, when BaP-treated BV2 cells were further incubated with FA (10, 20, 40, or 80 mg/mL) for another 24 h, a significant reduction in BaP-induced DNA damage and the release of multiple pro-inflammatory and cytotoxic factors (including interleukin-1ß, interleukin-6, NO, and ROS) was observed in a dose-dependent manner. Further study revealed that the microglial NOD-like receptor (NLR) family pyrin domain-containing 3 (NLRP3) signaling pathway was involved in the protective effect of FA. Taken together, these results suggested that FA suppressed BaP-induced toxicity in microglia, and thus may exert neuroprotective effects by inhibiting microglia-mediated pro-inflammatory response.

13.
J Cell Mol Med ; 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31755246

RESUMO

Emerging evidence illustrates the critical roles of long non-coding RNAs (lncRNAs) in the diabetes. However, the deepgoing regulation of lncRNA PVT1 in the diabetic cataract (DC) is still unclear. Here, present research investigates the pathologic roles and underlying mechanism by which lncRNA PVT1 regulates the DC pathogenesis. Human lens epithelial (HLE) B-3 cells were induced by the high glucose (HG) to simulate the DC microenvironment models. Results revealed that lncRNA PVT1 expression was up-regulated in the HG-induced HLE B-3 cells as compared to the normal glucose group. Transcription factor SP1 could bind with the promoter region of PVT1 and activate its transcription. Functionally, PVT1 knock-down could repress the proliferation and promote the apoptosis of HLE B-3 cells. Mechanistically, PVT1 acted as the 'miRNA sponge' to target miR-214-3p/MMP2 axis. This finding revealed a novel insight of lncRNA PVT1 for the DC pathogenesis, providing an inspiration for the DC mechanism.

14.
Eur J Pharmacol ; : 172787, 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31712061

RESUMO

Zinc finger E-box binding homeobox 1 (ZEB1) (previously known as TCF8), a transcriptional repressor, is a member of the zinc-finger family of proteins. Numerous studies have demonstrated that abnormal expression of ZEB1 in many types of liver disease including hepatocellular carcinoma (HCC). Liver fibrosis is the basis and central link in the progression of liver disease. Thereby, the function of ZEB1 in liver fibrosis has been investigated. The aim of the present study was to investigate the role of ZEB1 in liver fibrosis and to elucidate the mechanism. In this study, we explored the effect of ZEB1 in hepatic stellate cells (HSCs) activation and the regulatory mechanism of the Wnt/ß-catenin signaling pathway. Additionally, ZEB1 positively regulated the expression levels of α-SMA and Col.I in vivo and in vitro, which were correlated with the activated HSCs. Furthermore, overexpression of ZEB1 could inhibit HSCs apoptosis and promote IL-6 and TNF-α secretion in LX-2 cells. Conversely, ZEB1 silencing led to the promotion of cell proliferation and the reduction of IL-6 and TNF-α secretion in LX-2 cells. Mechanically, canonical Wnt/ß-catenin signaling pathway could be regulated by ZEB1. Collectively, the data suggested that ZEB1 might play a significant role in the activation of LX-2 cells, and Wnt/ß-catenin signaling pathway might participate in this progression.

15.
J Nat Prod ; 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31736307

RESUMO

Nine new alkaloids, (+)-1, (-)-1, 2, (+)-3, (-)-3, and 4-7, along with five known compounds (8-12), were obtained from the branches and leaves of Elaeocarpus angustifolius. The alkaloids were structurally characterized by NMR and MS data. The absolute configurations of (+)-1, (-)-1, (+)-3, and (-)-3 were determined by comparing their experimental and computed electronic circular dichroism spectra. (±)-8,9-Dehydroelaeocarpine (5), (±)-9-epielaeocarpine cis-N-oxide trifluoroacetate (6), and (±)-elaeocarpine trifluoroacetate (9) exerted weak inhibitory activities against butyrylcholinesterase with IC50 values of 39, 29, and 35 µM, respectively, while that of tacrine, the positive control, was 0.07 ± 0.01 µM. This is the first report of the cholinesterase inhibitory activities of Elaeocarpus alkaloids.

16.
BMC Med Genomics ; 12(1): 159, 2019 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-31703587

RESUMO

BACKGROUND: The microRNA-17-92 (miR-17-92) cluster is one of the most extensively studied miRNA clusters. Abnormal expression of the cluster has been found to play important role in different kinds of human diseases, including ischemic stroke (IS). The aim of our study was to investigate the association between three polymorphisms (rs1491034, rs9301654 and rs982873) in the promoter of the miR-17-92 cluster and risk of IS. METHODS: Three hundred and ninety-eight patients with IS and 397 control subjects were included. The genotypes of the three polymorphisms were determined by Snapshot SNP genotyping assay. Relative expression of the cluster in peripheral blood mononuclear cells (PBMCs) of cases and controls were examined by quantitative real-time PCR. RESULTS: Significant association between rs9301654 polymorphism and risk of IS were observed basing on genotype, model and allele analyses (GA vs. AA: adjusted OR = 0.63, 95% CI: 0.41~0.97, P = 0.037; GG vs. AA: adjusted OR = 0.23, 95% CI: 0.07~0.78, P = 0.018; GA + GG vs. AA: adjusted OR = 0.57, 95% CI: 0.38~0.87, P = 0.009; GA + AA vs. GG: adjusted OR = 0.27, 95% CI: 0.08~0.89, P = 0.032; G vs. A: adjusted OR = 0.58, 95% CI: 0.40~0.83). Haplotype analysis showed that TGC and TGT haplotypes were associated with decreased risk of IS (OR = 0.59, 95% CI: 0.40~0.87, P = 0.007 for TGC haplotype; OR = 0.21, 95% CI: 0.06~0.75, P = 0.009 for TGT haplotype). Importantly, we found the expression of miR-17-5p was significant higher while miR-19a-3p was significant lower in patient with IS compared with the control group (P < 0.01), and patients with rs9301654GG or GA genotype displayed lower level of miR-19a-3p compared with the AA genotype (P < 0.01). CONCLUSIONS: Our findings indicated that rs9301654 polymorphism in the promoter of miR-17-92 cluster may be associated with susceptibility of IS in the Chinese population. However, we found that rs9301654 polymorphism and its respective gene expression did not demonstrate consistent association with IS in the Chinese population. Further studies such as gene-gene interaction are warranted to reveal the role of miR-19a and its regulatory genes in the etiology of IS.

17.
Biochem Pharmacol ; 171: 113710, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31726046

RESUMO

Enteric viruses that inhabit the intestine have profound effects on innate and adaptive immunity of the gut and thus distant organs. Acute pancreatitis (AP) is a common abdominal inflammatory disease, in which gut bacteria play an indispensable part, particularly in the severe form with local and systemic complications. So far, little is known about the role of enteric viruses in the pathophysiology of AP. In this study, we evaluated the effect of enteric virus depletion by oral anti-viral cocktail (AVC) on caerulein (Cae)-hyperstimulation induced experimental AP and underlying mechanisms. We found that AVC treatment alleviated experimental AP, accompanied by suppressed innate immune cell infiltration and TLR9 expression and signaling in pancreas and intestine. Furthermore, AVC administration reduced AP-induced interleukin-6 (IL-6) production, IL-6-activated signal transducers and activators of transcription 3 (STAT3) signaling. Concordantly, expression of AP-induced STAT3-responsive chemokines, especially monocyte chemotactic protein-1 (MCP-1) and chemokine (C-X-C motif) ligand 1 (CXCL1) was reduced, thereby contributing to modulated pancreatic immune milieu. Treatment of mice with a toll-like receptor 9 (TLR9) agonist abolished the protective effect of AVC by activation of IL6/STAT3 signaling and downstream chemokine production. Conversely, treatment of mice with TLR9 antagonists, mimicking AVC, exerted protective effects against AP. Collectively, these results suggest that depletion of enteric viruses protects mice from experimental AP through inhibiting TLR9 signaling. Our study therefore implies a previously unrecognized role of enteric viruses in AP.

18.
Mol Plant ; 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31706032

RESUMO

Symbiotic microorganisms improve nutrient uptake by plants. To initiate mutualistic symbiosis with arbuscular mycorrhizal (AM) fungi, plants perceive Myc factors, including lipochitooligosaccharides (LCOs) and short-chain chitooligosaccharides (CO4/CO5), secreted by AM fungi. However, the molecular mechanism of Myc factors perception remains elusive. Here, we identified a heteromer of LysM receptor-like kinases, OsMYR1/OsLYK2 and OsCERK1, that mediates perception of AM fungi in rice. CO4 directly binds to OsMYR1, promoting the dimerization and phosphorylation of this receptor complex. Compared to control plants, Osmyr1 and Oscerk1 mutant rice plants are less sensitive to Myc factors and show decreased AM colonization. We engineered transgenic rice by expressing chimeric receptors that respectively replaced the ectodomains of OsMYR1 and OsCERK1 with those from the homologous Nod factor receptors MtNFP and MtLYK3 of Medicago truncatula. Transgenic plants displayed increased calcium oscillations in response to Nod factors compared to control rice. Our findings reveal a mechanism for mycorrhizal symbiotic signal perception in rice, and the ectopic expression of chimeric Nod/Myc receptors achieves a potentially important step towards generating cereals that host nitrogen-fixing bacteria.

19.
Theriogenology ; 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31708196

RESUMO

The objective was to determine the effects of pregnancy status on oxylipin profiles and eicosanoid metabolizing enzymes and in corpora lutea (CL) or endometrial (caruncle; CAR and intercaruncle; IC) tissues. Angus crossed cattle were synchronized with the CO-Synch protocol and artificially inseminated (AI). Sixteen days after AI, cattle were euthanized, and reproductive tracts collected from 6 non-pregnant and 6 pregnant cows. Oxylipin profiles and concentrations of progesterone (P4) were obtained from CL tissues. The activity of cytochrome P450 1A (CYP1A) and UDP-glucuronosyltransferase (UGT) enzymes were determined using specific luminogenic substrates. Data were analyzed using the MIXED procedure of SAS, and the model included pregnancy status. Corpora lutea of pregnant cattle contained greater (P < 0.05) concentrations of 9,10-DiHODE, 15,16-DiHODE, and 9,10-DiHOME. These oxylipins have been observed to increase cellular proliferation and vasodilation. Activity of CYP1A in the CL and UGT in CAR and IC was not different (P > 0.05) between pregnant and non-pregnant cattle. In the CL, activity of UGT was decreased (P < 0.05) in pregnant vs. non-pregnant cattle. The decrease in CL UGT activity during pregnancy indicates alterations in local hormone metabolism, while no differences in CL weight nor amount of P4 in CL were different between pregnant and non-pregnant cattle. Moreover, the increase in specific concentrations of oxylipins in the CL may indicate a novel pathway of steroid and eicosanoid metabolism during maternal recognition of pregnancy.

20.
Nanotechnology ; 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31751955

RESUMO

Since the first report on solid-state perovskite solar cell (PSC) with ~10% power conversion efficiency (PCE) and 500 h-stability in 2012, tremendous efforts have been being devoted to develop PSCs with higher PCE, longer stability and recycling hazardous lead waste. As a result, PCE over 23% was recorded in 2018 and stability over 10,000 h was reported. Beyond photovoltaics, lead halide perovskite materials demonstrated superb properties when they were applied to flat-panel X-ray detector and non-volatile resistive switching memory. In this review, progresses of lead halide perovskite in photovoltaics, X-ray imaging and memristor are investigated. Pb-based PSCs and non-Pb-based PSCs are compared, where technologies of non-Pb-based PSCs are not matured for commercialization. Pb-based PSCs were found to be highly suitable for both terrestrial and space photovoltaics. Higher sensitivity under low dose rate observed from lead halide perovskite suggests a bright future of perovskite X-ray imaging system. Moreover, high on/off ratio and low energy consumption observed in resistive switching enable perovskite to be promising candidate for high density memristor.

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