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1.
Behav Brain Res ; 377: 112249, 2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31541673

RESUMO

Negative mood states are hypothesized to increase the risk for overeating among restrained eaters. However, neurophysiological features of inhibitory control during negative mood states among restrained eaters are poorly understood. To address this gap, we aimed to assess event related potentials (ERPs) associated with food-specific inhibitory control among successful restrained eaters (SREs, n = 17), unsuccessful restrained eaters (UREs, n = 18), and non-restrained eaters (NREs, n = 18) engaged in a food-related go/no-go task during negative versus neutral mood states. Compared to neutral mood states, negative mood states were related to comparatively greater no-go N2a amplitudes in the entire sample. Regarding group differences, no-go N2a amplitudes of SREs were greater than those of UREs across negative and neutral mood states. However, no-go P3 amplitudes of SREs decreased significantly during the negative mood state while no change was observed for other groups. Results suggest that negative mood states may interfere with conflict monitoring and behavioral inhibition in general, but inhibitory control over food may be enhanced among SREs during negative mood states relative to UREs. Results may provide psychophysiological bases for understanding why SREs succeed and UREs fail in controlling appetitive responses to external food cues.

2.
Appl Opt ; 58(30): 8295-8301, 2019 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-31674504

RESUMO

A grating projection shape measurement system has been a commonly used method in the field of three-dimensional (3D) reconstruction in recent years, and global point cloud registration is a key step in this method. However, in the registration process, a large amount of low-precision overlapping redundant data (ORD) is generated between adjacent camera stations, which will seriously affect the speed and accuracy of later modeling. Therefore, how to eliminate these low-precision ORD is a major problem to be solved at present. Determining all overlapping 3D point pairs between two adjacent stations and deleting the points with low precision in the point pairs is the key to solving this problem. Therefore, based on an omnidirectional rotation measurement system, combined with the constraint relationships between the projection space and the acquisition space in the global registration process and the stereo-matching method of space conversion, an elimination algorithm for ORD with a two-dimensional (2D) phase constraint and a 2D pixel constraint is proposed. The experimental results show that the proposed algorithm can faster locate overlapping 3D point pairs between adjacent stations, with a higher elimination rate, and the accuracy of the overall point cloud is higher after the redundancy elimination.

3.
Opt Express ; 27(19): 27046-27061, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31674573

RESUMO

We present an efficient and faithful hyperentanglement purification protocol (hyper-EPP) for three-photon system in mixed hyperentangled Greenberger-Horne-Zeilinger states with bit-flip errors in both spatial-mode and polarization degrees of freedom (DOFs), resorting to the fidelity-robust quantum gates and hyperentanglement link. Our high-efficiency hyper-EPP comes from two aspects. One is to pump the higher-fidelity hyperentanglement from different three-photon systems into the same three-photon system with fidelity-robust swap gates, the other is to reproduce some hyperentangled three-photon systems from hyperentangled two-photon subsystems based on hyperentanglement link. Moreover, as the infidelity originating from imperfect single-photon scattering can be heralded as a failure by triggering a detector, our hyper-EPP operates faithfully with the present quantum circuits. Furthermore, our hyper-EPP can be directly extended to purify multiple photon systems entangled in one DOF or hyperentangled in multiple DOFs.

4.
Opt Express ; 27(19): 27151-27158, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31674581

RESUMO

We demonstrate a tunable gain-switched Dy3+-doped ZBLAN fiber laser around 3 µm, for the first time, to the best of our knowledge. The pump source is a homemade actively Q-switched Yb3+-doped silica fiber laser at 1.1 µm, yielding a repetition rate of 80 kHz and a pulse width of 300 ns. A plane-ruled grating in a Littrow configuration functions as the tuning element. At the launched pump power of 2.78 W, stable gain-switched pulses tunable within a ~300 nm range of 2800~3095 nm are achieved. When tuning the wavelength to 2946.5 nm, a maximum output power of 218.6 mW with a repetition rate of 80 kHz is obtained. The corresponding pulse width and energy are 530 ns and 2.73 µJ, respectively. The results imply that gain-switching of Dy3+-doped ZBLAN fiber laser is an alternative way for mid-infrared nanosecond pulse generation around 3 µm.

5.
Endocr Relat Cancer ; 26(12): 829-841, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31671400

RESUMO

Thyroid cancer is the most frequent endocrine tumor with a growing incidence worldwide. However, common diagnostic strategy for thyroid cancer classification is hardly to make a proper diagnosis in some cases. To assist classical approach, this study used metabolomics to screen and validate biomarkers from serum and urinary for papillary thyroid cancer (PTC). Overall, 124 untreated PTC, 76 untreated benign thyroid nodule (BTN), and 116 healthy control (HC) were collected in this study. Thirty-six differential metabolites were screened from non-targeted metabolomics with a discovery sample set in comparison with HC and BTN. Serum ß-hydroxybutyrate (BHB), docosahexaenoic acid (DHA), 1-methyladenosine (1-MedA), pregnanediol-3-glucuronide (PdG), urinary nicotinic acid mononucleotide (NAM) and xanthosine (Xan) were validated to be significantly differential by targeted metabolomics in validation set. The logistic regression model incorporating six biomarkers had excellent discrimination from receiver-operating characteristics (ROC) analysis, with area under the receiver-operating characteristic curve (AUC) of 0.943 (95% CI 0.902 to 0.983) and 0.952 (95% CI 0.921 to 0.983) for female alone and female + male samples, respectively. The prediction accuracy and false-negative rate in the real setting of one PTC to ten suspicious nodules were 84.7 and 17.7% with the threshold at probablity of 0.5. Results of a double-blind study for PTC and BTN had true positive value of 100% and true negative value of 91.7%. To conclude, BHB, DHA, 1-MedA, PdG, NAM and Xan are suitable biomarkers for PTC, and logistic regression models with the six biomarkers can be potentially used as clinical diagnosis.

6.
Reproduction ; 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31671403

RESUMO

Microspherule protein 1 (MCRS1, also known as MSP58) is an evolutionarily conserved protein that has been implicated in various biological processes. Although a variety of functions have been attributed to MCRS1 in vitro, mammalian MCRS1 has not been studied in vivo. Here we report that MCRS1 is essential during early murine development. Mcrs1 mutant embryos exhibit normal morphology at the blastocyst stage but cannot be recovered at gastrulation, suggesting an implantation failure. Outgrowth (OG) assays reveal that mutant blastocysts do not form a typical inner cell mass (ICM) colony, the source of embryonic stem cells (ESCs). Surprisingly, cell death and histone H4 acetylation analysis reveal that apoptosis and global H4 acetylation are normal in mutant blastocysts. However, analysis of lineage specification reveals that while the trophoblast and primitive endoderm are properly specified, the epiblast lineage is compromised and exhibits a severe reduction in cell number. In summary, our study demonstrates the indispensable role of MCRS1 in epiblast development during early mammalian embryogenesis.

7.
J Biol Chem ; 2019 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-31666338

RESUMO

Inositol-requiring enzyme 1 (IRE1) is an endoplasmic reticulum (ER)-resident transmembrane protein that senses ER stress and is evolutionarily conserved from yeast to humans. IRE1 possesses both Ser/Thr protein kinase and endoribonuclease (RNase) activities within its cytoplasmic domain and is activated through autophosphorylation and dimerization/oligomerization. It mediates a critical arm of the unfolded protein response (UPR) to manage ER stress provoked by lumenal overload of unfolded/misfolded proteins. Emerging lines of evidence have revealed that in mammals, IRE1α functions as a multifunctional signal transducer that responds to metabolic cues and nutrient stress conditions, exerting profound and broad effects on metabolic homeostasis. In this review, we cover recent advances in our understanding of how IRE1α integrates a variety of metabolic and stress signals and highlight its tissue-specific or context-dependent metabolic activities. We also discuss how dysregulation of this metabolic stress sensor during handling of excessive nutrients in cells contributes to the progression of obesity and metabolic disorders.

8.
Artigo em Inglês | MEDLINE | ID: mdl-31670455

RESUMO

Photocatalytic overall water splitting has been recognized as a promising approach to convert solar energy into hydrogen. However, most of the photocatalysts suffer from low efficiencies mainly due to the poor charge separation property. Herein, taking a model semiconductor gallium nitride (GaN) as an example, we uncovered that photogenerated electrons and holes can be spatially separated to the nonpolar and polar surfaces of GaN nanorod arrays, which is presumably ascribed to the different surface band bending induced by the surface polarity. The photogenerated charge separation efficiency of GaN can be enhanced significantly from ~8% to more than 80% via co-exposing polar and nonpolar surfaces. Furthermore, spatially assembling of reduction and oxidation cocatalysts selectively on the nonpolar and polar surfaces remarkably boosts photocatalytic overall water splitting, with the quantum efficiency increased from 0.9% for the film photocatalyst to 6.9% for the nanorod arrays photocatalyst.

11.
Int J Mol Sci ; 20(20)2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31600869

RESUMO

Tomato chlorosis virus (ToCV) is widespread, seriously impacting tomato production throughout the world. ToCV is semi-persistently transmitted by Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae). Currently, insect olfaction is being studied to develop novel pest control technologies to effectively control B. tabaci and whitefly-borne virus diseases. Despite current research efforts, no report has been published on the role of odorant-binding proteins (OBPs) in insect preference under the influence of plant virus. Our previous research showed that viruliferous B. tabaci preferred healthy plants at 48 h after virus acquisition. In this study, we determined the effect of OBPs on the host preference interactions of ToCV and whiteflies. Our results show that with the increase in acquisition time, the OBP gene expressions changed differently, and the OBP3 gene expression showed a trend of first rising and then falling, and reached the maximum at 48 h. These results indicate that OBP3 may participate in the host preference of viruliferous whiteflies to healthy plants. When the expression of the OBP3 gene was knocked down by an RNA interference (RNAi) technique, viruliferous Mediterranean (MED) showed no preference and the ToCV transmission rate was reduced by 83.3%. We conclude that OBP3 is involved in the detection of plant volatiles by viruliferous MED. Our results provide a theoretical basis and technical support for clarifying the transmission mechanism of ToCV by B. tabaci and could provide new avenues for controlling this plant virus and its vectors.

12.
Mar Pollut Bull ; 145: 547-554, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31590822

RESUMO

Microplastics are becoming a global concern due to their potential to accumulate pollutants in aquatic environments. In this paper, sulfamethazine (SMT) sorption onto six types of microplastics, including polyamide (PA), polyethylene (PE), polyethylene terephthalate (PET), polypropylene (PP), polystyrene (PS), and polyvinyl chloride (PVC) was investigated by experimental and molecular dynamics simulation methods. The experimental results indicated that SMX sorption reached equilibrium within 16 h. The kinetics of SMT sorption by PA, PVC, PE, and PP could be fitted by pseudo first-order model, while SMT sorption by PA and PET could be described by pseudo second-order model. The partition coefficient Kd values were 38.7, 23.5, 21.0, 22.6, 18.6 and 15.1 L·kg-1 for PA, PE, PS, PET, PVC and PP, respectively. SMT sorption onto microplastics decreased when pH and salinity increased. The molecular dynamics simulation results indicated that the main mechanisms involved in sorption are electrostatic and Van der Waals interaction.

13.
Oncogene ; 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31591477

RESUMO

Bmi1 is overexpressed in one-third of hepatocellular carcinoma (HCC) patients and acts as an oncogene in hepatocarcinogenesis. However, the underlying mechanism is unclear. The role of TGFß signalling in HCC is not well defined as well. Here, we report that TGFß2 is a target of Bmi1 in HCC and has a tumour-suppressing role. In Bmi1-knockout mouse livers and HCC cell lines, TGFß2/SMAD cascade proteins were upregulated. TGFß2 expression was inversely correlated with Bmi1 expression in human and mouse HCC tissues. In vitro, Bmi1 knockdown activated TGFß2/SMAD signalling and led to cell apoptosis via upregulation of p15 and p21. TGFß2 inhibition rescued the inhibitory effect of Bmi1 knockdown on HCC cell survival, proliferation, and cell-cycle progression. In vivo, restoration of TGFß2 expression blocked Bmi1/Ras-driven hepatocarcinogenesis in mice. Chromatin immunoprecipitation and luciferase reporter assays revealed that Bmi1 repressed TGFß2 expression by binding to its promoter as a co-factor of polycomb repressor complex 1. Our findings elucidate the molecular mechanism underlying hepatic Bmi1-driven carcinogenesis and highlight the importance of TGFß2 as a tumour suppressor in HCC development.

14.
ACS Appl Mater Interfaces ; 11(42): 38654-38662, 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31566358

RESUMO

In virtue of their distinctive superiorities, lithium-sulfur (Li-S) batteries were deemed as novel and potential energy storage equipment. However, the low actual energy density and rapid capacity fading are still hindering their practical applications. Herein, MXene-based Co, N-codoped porous carbon nanosheets (MCoNPCNSs) are first developed as sulfur hosts by in situ self-assembly of the bimetallic zeolite imidazole framework on Ti3C2Tx MXene nanosheets followed by calcining and etching treatments. Co, N codoping on the one hand highly enhances the adsorptivity to polysulfides and on the other hand significantly promotes the kinetics of sulfur cathodes. Therefore, the MCoNPCNSs/S-M-PP electrode achieves a high capacity of 1340.2 mA h g-1 in the first-cycle discharge process at 0.2 C and an exceptional capacity retention of 914.7 mA h g-1 after 1000 cycles at 1 C. Moreover, the integrated structure of the cathode and separator imparts the MCoNPCNSs/S-M-PP electrode a significantly elevated gravimetric energy density of 1211.8 W h kg-1. Therefore, the integrated MCoNPCNSs/S-M-PP electrode provides a delighted direction for constructing the potentially practical Li-S batteries.

15.
Plant Sci ; 289: 110288, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31623791

RESUMO

Citric acid homeostasis patterns and its content are diversified among the fruits of citrus cultivars, but the cause remained unclear. In this study we showed that changes of citric acid content were highly associated with the expression profiles of a P-type proton pump gene (CsPH8) in the fruits of six citrus cultivars; moreover, analysis of 21 different fruit samples indicated that the correlation coefficient between titratable acid content and CsPH8 transcript level was 0.5837 with a significant level (P < 0.05). Overexpression of CsPH8 in acidless pumelo juice sacs, strawberry fruit, and tomato fruit significantly increased the titratable acid or citric acid content besides the gene transcript level. On another hand, RNA interference of CsPH8 in acidic pumelo juice sacs significantly decreased the CsPH8 transcript level and the titratable acid or citric acid content as well. In addition, severe drought significantly increased the CsPH8 transcript level besides the titratable acid content. Taken together, these findings address the function of CsPH8 in citrus vacuolar acidification, confirm that CsPH8 plays a key role in the variation of citric acid content, and supported that the acid fluctuation influenced by drought, is at least partly due to the change of CsPH8 transcript level.

16.
Hum Vaccin Immunother ; : 1-9, 2019 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-31625792

RESUMO

China has a shocking number of tetanus cases in the world, but little research has investigated doctors' knowledge of and practices in tetanus prophylaxis, especially tetanus vaccination. To this end, we conducted a pilot study on 197 emergency doctors using a mixed method of web-based (163; 82.8%) and paper-based (34; 17.2%) surveys. There was no difference between the two groups except for the percentage of doctors receiving a tetanus booster in the past 10 years and the responses to question 11. Surprisingly, only 28.9% of doctors had received formal training on tetanus immunization and only 21.3% had themselves received a tetanus vaccine booster in the past 10 years. Furthermore, only 14.2% of the respondents confirmed the availability of the tetanus vaccine in their respective institutions. Finally, the correct rates and Tetanus-immune-globulin (TIG)-only option rates for questions 11-15 were unsatisfactory. Our results showed that most emergency doctors' knowledge and practices strayed from the recommendations of Advisory Committee on Immunization Practices (ACIP): 1) TIG alone for most trauma patients instead of vaccine was an overused treatment approach. 2) Most of the emergency doctors lacked formal training on and knowledge of tetanus vaccination. 3) Even the emergency doctors themselves were not properly vaccinated. 4) The tetanus vaccine was only available in a small number of the respondents' institutions. The findings of this study suggest an urgent need to improve this dire situation.

17.
Plant Mol Biol ; 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31621003

RESUMO

KEY MESSAGE: At least eight MGT genes were identified in citrus and PtrMGT5 plays important role in maintaining Mg homeostasis in citrus by getting involved in the Mg absorption and transport. Magnesium (Mg) is an essential macronutrient for plant growth and development, and the magnesium transporter (MGT) genes participate in mediate Mg2+ uptake, translocation and sequestration into cellular storage compartments. Although several MGT genes have been characterized in various plant species, a comprehensive analysis of the MGT gene family in citrus is still uncharacterized. In this study, eight PtrMGT genes were identified through genome-wide analyses. Phylogenetic analyses revealed that PtrMGT genes were classified into five distinct subfamilies. A quantitative RT-PCR analysis showed that eight PtrMGT genes were expressed in all of the detected tissues and they mainly expressed in the vegetative organs. Expression analyses revealed the PtrMGT genes responded to various Mg deficiency stresses, including absolute Mg deficiency and antagonistic Mg deficiency which caused by low pH or Al toxicity. PtrMGT5, which localizes to the plasma membrane and was transcriptionally active, was functionally characterized. PtrMGT5 overexpression considerably enhanced absolute Mg deficiency and antagonistic Mg deficiency tolerance in transgenic Arabidopsis plants, which was accompanied by increased fresh weight and Mg content, whereas opposite changes were observed when PtrMGT5 homolog in Valencia Orange callus was knocked down. Taken together, PtrMGT5 plays important role in maintaining Mg homeostasis in citrus by getting involved in the Mg absorption and transport.

18.
J Phys Chem A ; 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31644288

RESUMO

Room-temperature ATR-FTIR spectra of the structurally characterized crystalline lithium salt Li2(H2O)4(B12F12), which contains a cyclic S4 symmetry (H2O)4 cluster, and several partially or completely deuterated isotopologs, suggest the following conclusions: (i) B and E normal modes gave rise to two distinguishable ν(OHbound) bands, separated by 42 cm-1, two distinguishable ν(OHfree) bands, separated by 13 cm-1, and two distinguishable δ(HOH) bands, separated by 19 cm-1 in the FTIR spectrum of Li2(H2O)4(B12F12); (ii) B and E normal modes gave rise to two distinguishable ν(ODbound) bands separated by 20 cm-1 in the FTIR spectrum of Li2(D2O)4(B12F12); (iii) coupling between ν(OHbound) and ν(OHfree) normal modes or between ν(ODbound) and ν(ODfree) normal modes is weak, but finite, and resulted in shifts of 4-10 cm-1 for the respective bands in spectra of Li2(H2O)4(B12F12) vs. Li2(HOD)(D2O)3(B12F12) or in spectra of Li2(D2O)4(B12F12) vs. Li2(HOD)(H2O)3(B12F12); and (iv) a δ(DOD) band for an S4 (D2O)4 cluster, at ca. 1202 cm-1, was observed for the first time. In addition, FTIR spectra of the lithium salt containing cyclic [(HOD)(H2O)3] or [(HOD)(D2O)3] clusters are the first examples in which bands that are unambiguously assigned to both HO-D···O and DO-H···O hydrogen bonds in the same sample have been observed for a water tetramer.

19.
Mol Cancer Ther ; 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31645443

RESUMO

Ceramide (Cer) is an active cellular sphingolipid that can induce apoptosis or proliferation-arrest of cancer cells. Nanoparticle-based delivery offers an effective approach for overcoming bioavailability and biopharmaceutics issues attributable to the pronounced hydrophobicity of Cer. Missense mutations of the protein p53, which have been detected in approximately 42% of cancer cases, not only lose the tumor suppression activity of wild-type p53, but also gain oncogenic functions promoting tumor progression and drug-resistance. Our previous works showed that cellular Cer can eradicate cancer cells that carry a p53 deletion-mutation by modulating alternative pre-mRNA splicing, restoring wild-type p53 protein expression. Here, we report that new Cer-RUB nanomicelles considerably enhance Cer in-vivo bioavailability and restore p53-dependent tumor suppression in cancer cells carrying a p53 missense mutation. Natural rubusoside (RUB) encapsulated short-chain C6-Cer so as to form Cer-RUB nanomicelles (~32 nm in diameter) that substantially enhanced Cer solubility and its levels in tissues and tumors of mice dosed intraperitoneally. Intriguingly, Cer-RUB nanomicelle treatments restored p53-dependent tumor suppression and sensitivity to cisplatin in OVCAR-3 ovarian cancer cells and xenograft tumors carrying p53 R248Q mutation. Moreover, Cer-RUB nanomicelles showed no signs of significant nonspecific toxicity to noncancerous cells or normal tissues, including bone marrow. Further, Cer-RUB nanomicelles restored p53 phosphorylated protein and downstream function to wild-type levels in p53 R172H/+ transgenic mice. Altogether, this study, for the first time, indicates that natural Cer-RUB nanomicelles offer a feasible approach for efficaciously and safely targeting cancers carrying p53 missense mutations.

20.
Sheng Li Xue Bao ; 71(5): 732-740, 2019 Oct 25.
Artigo em Chinês | MEDLINE | ID: mdl-31646327

RESUMO

Parkinson's disease (PD) is the second most common neurodegenerative disease, characterized by loss of dopaminergic (DA) neurons in the dense part of the substantia nigra (SNpc). Postmortem analysis of PD patients and experimental animal studies found that microglial cell activation and increased levels of pro-inflammatory factors were common features of PD brain tissue. At the same time, the invasion and accumulation of peripheric immune cells were detected in the brain of PD patients. In this paper, peripheral inflammation across the blood-brain barrier (BBB), the misfolded α-synuclein (α-syn)-induced microglial cell activation and intracerebral inflammation in PD are summarized, providing potential therapeutic measures for delaying the onset of PD.

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