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1.
FASEB J ; 34(1): 1169-1181, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31914631

RESUMO

BHLHE40, a member of the basic helix-loop-helix transcription factor family, has been reported to play an important role in inflammatory diseases. However, the regulation and function of BHLHE40 in Helicobacter pylori (H pylori)-associated gastritis is unknown. We observed that gastric BHLHE40 was significantly elevated in patients and mice with H pylori infection. Then, we demonstrate that H pylori-infected GECs express BHLHE40 via cagA-ERK pathway. BHLHE40 translocates to cell nucleus, and then binds to cagA protein-activated p-STAT3 (Tyr705). The complex increases chemotactic factor CXCL12 expression (production). Release of CXCL12 from GECs fosters CD4+ T cell infiltration in the gastric mucosa. Our results identify the cagA-BHLHE40-CXCL12 axis that contributes to inflammatory response in gastric mucosa during H pylori infection.

2.
Org Lett ; 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31793306

RESUMO

A gold(I) complex is reported. Interestingly, crystals of the gold(I) complex exhibit an excellent excitation wavelength-dependent emission effect at room temperature. Notably, a nearly pure white emission with Commission Internationale de L'Eclairage (CIE) 1931 chromaticity coordinates of (0.32, 0.33) is obtained upon excitation with 406 nm light.

3.
Plant Biotechnol J ; 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31820843

RESUMO

Glucosinolates (GSLs), whose degradation products have been shown to be increasingly important for human health and plant defense, compose important secondary metabolites found in the order Brassicales. It is highly desired to enhance pest and disease resistance by increasing the leaf GSL content while keeping the content low in seeds of Brassica napus, one of the most important oil crops worldwide. Little is known about the regulation of GSL accumulation in the leaves. We quantified the levels of 9 different GSLs and 15 related traits in the leaves of 366 accessions, and found that the seed and leaf GSL content were highly correlated (r = 0.79). A total of 78 loci were associated with GSL traits, and five common and eleven tissue-specific associated loci were related to total leaf and seed GSL content. Thirty-six candidate genes were inferred to be involved in GSL biosynthesis. The candidate gene BnaA03g40190D (BnaA3.MYB28) was validated by DNA polymorphisms and gene expression analysis. This gene was responsible for high leaf/low seed GSL content, and could explain 30.62% of the total leaf GSL variation in the low-seed GSL panel and was not fixed during double-low rapeseed breeding. Our results provide new insights into the genetic basis of GSL variation in leaves and seeds and may facilitate the metabolic engineering of GSLs and the breeding of high leaf/low seed GSL content in B. napus.

4.
Cell Host Microbe ; 26(6): 836-843.e3, 2019 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-31787524

RESUMO

African swine fever virus (ASFV) is a large double-stranded DNA virus with an icosahedral multilayered structure. ASFV causes a lethal swine hemorrhagic disease and is currently responsible for widespread damage to the pork industry in Asia. Neither vaccines nor antivirals are available and the molecular characterization of the ASFV particle is outstanding. Here, we describe the cryogenic electron microscopy (cryo-EM) structure of the icosahedral capsid of ASFV at 4.6-Å. The ASFV particle consists of 8,280 copies of the major capsid protein p72, 60 copies of the penton protein, and at least 8,340 minor capsid proteins, of which there might be 3 different types. Like other nucleocytoplasmic large DNA viruses, the minor capsid proteins form a hexagonal network below the outer capsid shell, functioning as stabilizers by "gluing" neighboring capsomers together. Our findings provide a comprehensive molecular model of the ASFV capsid architecture that will contribute to the future development of countermeasures, including vaccines.

5.
Surg Endosc ; 2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31811454

RESUMO

BACKGROUND AND AIMS: Endoscopic resection (ER) is an effective and safe method for gastric submucosal tumors, mostly composed of gastrointestinal stromal tumors and leiomyomas. The role of ER in gastric schwannoma (GS) has rarely been described. Our aim was to evaluate the efficacy and safety of ER for GS. METHODS: This is a retrospective study in consecutive patients who underwent ER for GS from March 2013 to October 2018 at our center. Clinicopathological, endoscopic, and follow-up data were collected and analyzed. RESULTS: A total of 16 consecutive patients (9 females, 56.3%) were included, with a mean age of 50.4 years (range 25-75 years). The mean tumor size was 22.9 ± 15.1 mm (range 10-55 mm). Thirteen tumors (81.3%) were located in the middle third of the stomach and 12 tumors (75%) grew with intraluminal pattern. Endoscopic submucosal excavation (ESE) was performed in 7 patients while endoscopic full-thickness resection (EFTR) was done in 9 patients. R0 resection was achieved in 14 patients (87.5%). The mean operative time was 91.6 ± 52.8 min (range 36-203 min) and the mean postoperative length of hospital stays was 8.3 ± 2.7 days (range 6-13 days). No adverse events were encountered except for fevers in 2 patients. No patients required surgical resection or intervention. During long-term follow-up of mean 21.8 months (range 6-62 months), no residue, recurrence, or metastasis was observed. CONCLUSIONS: ER is effective and safe for patients with GS with favorable long-term outcomes.

6.
Mol Biol Rep ; 2019 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-31853767

RESUMO

Leucine aminopeptidase 3 (LAP3) is an important proteolytic enzyme that catalyzes the hydrolysis of leucine residues from the amino termini of protein or peptide substrates and plays a critical role in protein metabolism and growth. In the present study, we investigated the full-length cDNA sequence of the LAP3 gene in Sinonovacula constricta (ScLAP3) using expressed sequence tags and rapid amplification of cDNA ends. The full-length ScLAP3 cDNA was 2885 bp, with a 1560 bp open reading frame encoding 519 amino acids. Sequence analysis revealed that ScLAP3 shared 70.9% identity with LAP3 from the blood clam Tegillarca granosa and 62.0-68.0% with other species. ScLAP3 was expressed in all six tested tissues, with significantly higher expression levels in the foot compared with mantle, adductor muscle, liver, gills, and siphon tissues in adults (P < 0.01). In the eight developmental stages, ScLAP3 expression gradually increased, with significantly higher levels in D-shaped larvae compared with other developmental stages (P < 0.01), suggesting that it may be involved in the formation of certain organs during early development. Association analysis identified three shared single nucleotide polymorphisms (SNPs), c.1073A > G, c.1139C > T and c.1154A > G in exons of ScLAP3 gene from 177 individuals of two groups, one selective strain and one wild population, which had significant effects on growth traits of S. constricta. The results provided candidate genetic markers to assist selective breeding of razor clams toward improved growth.

7.
Huan Jing Ke Xue ; 40(6): 2869-2876, 2019 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854681

RESUMO

With the rapid urbanization in China, soil environments are facing high risks. Taking a typical urbanized area as a case study, a total of 106 surface soil samples (0-20 cm) and 96 subsurface soil samples (20-40 cm) were collected to determine the concentrations of heavy metals, and then, the Nemerow index and Hankson index methods were used to evaluate their degrees of ecological risk. The spatial distributions of ecological risks were also explored. Experimental results showed that the concentrations of Cr, Ni, Cu, Zn, As, Cd, Pb, and Hg in surface soil samples were 2.87-84.64, 1.40-56.00, 2.75-125.05, 15.05-201.39, 1.46-89.92, 0.001-0.92, 15.29-160.07, and 0.006-0.52 mg·kg-1, respectively, and those in subsurface soil samples were 3.56-75.14, 1.65-71.58, 3.28-290.04, 17.99-296.94, 3.07-65.67, 0.02-1.00, 11.10-97.59, and 0.01-0.41 mg·kg-1, respectively. According to the risk control standards for soil contamination of agricultural land, approximately 71.70%, 40.57%, 4.72%, 3.77%, and 0.94% of Cd, Cu, Pb, As, and Zn, respectively, in the surface soil samples exceeded the standards, while 72.92%, 39.58%, 6.25%, 3.13%, 3.13%, and 1.04% of Cd, Cu, As, Zn, Pb, and Ni, respectively, in the subsurface soil samples exceeded the standards. Obviously, the pollution by Cd and Cu was the most severe in the research area, and the main contaminated areas were distributed in the northern part of the land. The soil environmental quality pollution assessment illustrated that high risk areas were distributed in the northern part of the research area too. The risk assessment results indicated that the main pollution factor was Cd, which is accordance with the serious pollution findings for Cd. In response to these results, effective management and remediation methods should be taken to control the soil environment pollution in this typical urbanized area.

8.
Lasers Med Sci ; 2019 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-31845042

RESUMO

To review and assess the efficacy of laser photobiomodulation for cartilage defect in animal models of knee osteoarthritis (KOA). Medline, Web of Science, and EMBASE were searched. Studies were considered if the global quality score of cartilage were parallelly reported between laser and untreated control groups. The methodological quality of each study was assessed using a modified 10-item checklist. The effect size was estimated by standardized mean difference (SMD) and pooled based on the random-effects model. Stratified analysis and regression analysis were conducted to partition potential heterogeneity. An adjusted significant level of 0.01 was acceptable. Five hundred eight initial search recordings were identified, of which 14 studies (including 274 animals) were included for quantitative analysis. The global quality scores mostly weighted by the structural integrity and chondrocyte distribution were measured by different four scales including Histologic Histochemical Grading System (HHGS), Osteoarthritis Research Society International (OARSI), Pineda, and Huang. There were considerable variances on laser parameters and irradiation time among those included studies. Overall, a moderate level of methodological qualities was determined. The synthesis results indicated that the SMD effect size was significantly larger in HHGS (z = 2.61, P = 0.01) and Huang (z = 4.90, P < 0.01) groups. Stratified by irradiance, SMD of low (< 1 W/cm2) but not high (≥ 1 W/cm2) level estimated significant difference (z = 5.62, P < 0.01). Meta-regression identified a significant association for SMDs and irradiation time (P < 0.01). Yet, Egger's test detected small study effect (P < 0.01). No individual study with significant variance was found in homogeneity tests. The results demonstrated the positive effect of laser photobiomodulation for cartilage defect in animal models of KOA under proper irradiance and adequate irradiation time.

9.
iScience ; 23(1): 100750, 2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31884170

RESUMO

DNA double-strand break (DSB) repair is critical for cell survival and genome integrity. Upon recognition of DSBs, repair proteins are transiently upregulated to facilitate repair through homologous recombination (HR) or non-homologous end joining (NHEJ). We present evidence that PRMT5 cooperates with pICln to function as a master epigenetic activator of DNA damage response (DDR) genes involved in HR, NHEJ, and G2 arrest (including RAD51, BRCA1, and BRCA2) to upregulate gene expression upon DNA damage. Contrary to the predominant role of PRMT5 as an epigenetic repressor, our results demonstrate that PRMT5 and pICln can activate gene expression, potentially independent of PRMT5's obligate cofactor MEP50. Targeting PRMT5 or pICln hinders repair of DSBs in multiple cancer cell lines, and both PRMT5 and pICln expression positively correlates with DDR genes across 32 clinical cancer datasets. Thus, targeting PRMT5 or pICln may be explored in combination with radiation or chemotherapy for cancer treatment.

10.
Spectrochim Acta A Mol Biomol Spectrosc ; 229: 117941, 2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-31884400

RESUMO

Three diverse supramolecular compounds, {[3-pmpmd]}n(1), {H2[3-pmpmd]·2NO3-}n(2), {H2[3-pmpmd]·2tbb}n(3), (where 3-pmpmd was N,N'-bis(3-pyridylmethyl)pyromellitic diimide; tbb was tertiary butyl benzoic acid) were synthesized and characterized by elemental analyses, IR spectroscopy, thermogravimetric analyses, and X-ray single-crystal structure analysis. The co-crystal anions affect their structural diversity. Compound 1 is a 1D stairway chain structure by perpendicular π⋯π interactions of pyromellitic diimide and the neighboring pyridine rings. Compound 2 is a typical 1D ladder chain structure by hydrogen bond of nitrate arranged in a parallel array. Compound 3 is a 1D zigzag chain structure of one 3-pmpmd and two tbb by parallel π⋯π interactions and hydrogen bond interactions. Thermal stabilities and fluorescence properties of all compounds were investigated. The solution of compound 2 in DMF can fluorescence sense for iodide ions by remarkably quenching fluorescence intensity.

11.
Opt Express ; 27(24): 34626-34638, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31878650

RESUMO

Camera calibration is an important part of high-precision optical measurement, which is especially difficult in the micro-nano field. Based on the integrated correlation calculation and CCD moiré method, this paper describes the development of a lens calibration technique called the Integrated Colour CCD Moiré Method (ICCM). The CCD moiré fringes, formed by superimposing a periodic optical signal of a specimen grating with a CCD target array or a Bayer filter array, significantly enlarges the deformation modulated by lens distortion and the calibration plate attitude (i.e. the rotation angle relative to the camera coordinate system). To measure lens distortion using CCD moiré, the deformation pattern that is governed by the lens distortion, specimen grating attitude and carrier was used to construct a CCD fringe image. If the constructed CCD fringe image based on the trial lens distortion and rotation angles have a maximum similarity to the captured CCD moiré image, the lens distortion and rotation angles are correctly inversed. Particle swarm optimisation algorithm was selected to search for the true value so that the accuracy and robustness could be improved. Numerical experiments verified that the ICCM method developed in this work can simultaneously inverse the lens distortion, rotation angle and the grating pitch with high precision. The lens distortion of the metallographic microscope has been successfully characterised by the developed method with an 833 nm pitch grating. Simulations and experiments showed that ICCM is an intuitive, accurate, anti-noise and robust distortion calibration method.

12.
Plant Biotechnol J ; 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31693306

RESUMO

Sclerotinia stem rot (SSR) caused by Sclerotinia sclerotiorum is a devastating disease of rapeseed (Brassica napus L.). To date, the genetic mechanisms of rapeseed' interactions with S. sclerotiorum are not fully understood, and molecular-based breeding is still the most effective control strategy for this disease. Here, Arabidopsis thaliana GDSL1 was characterized as an extracellular GDSL lipase gene functioning in Sclerotinia resistance. Loss of AtGDSL1 function resulted in enhanced susceptibility to S. sclerotiorum. Conversely, overexpression of AtGDSL1 in B. napus enhanced resistance, which was associated with increased reactive oxygen species (ROS) and salicylic acid (SA) levels, and reduced jasmonic acid levels. In addition, AtGDSL1 can cause an increase in lipid precursor phosphatidic acid levels, which may lead to the activation of downstream ROS/SA defence-related pathways. However, the rapeseed BnGDSL1 with highest sequence similarity to AtGDSL1 had no effect on SSR resistance. A candidate gene association study revealed that only one AtGDSL1 homolog from rapeseed, BnaC07g35650D (BnGLIP1), significantly contributed to resistance traits in a natural B. napus population, and the resistance function was also confirmed by a transient expression assay in tobacco leaves. Moreover, genomic analyses revealed that BnGLIP1 locus was embedded in a selected region associated with SSR resistance during the breeding process, and its elite allele type belonged to a minor allele in the population. Thus, BnGLIP1 is the functional equivalent of AtGDSL1 and has a broad application in rapeseed S. sclerotiorum-resistance breeding.

13.
Plant Physiol Biochem ; 146: 294-302, 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31783205

RESUMO

Brassica napus (rapeseed) serves as a main source of edible oil, and the oil's quality is mainly determined by the relative proportions of fatty acids. A high oleic acid concentration in B. napus oil increases its shelf life and oxidative stability. Therefore, attaining a high oleic acid concentration is necessary to enhance the nutritional quality of rapeseed oil. Here, an association study of candidate genes was conducted using a population of 324 genetically diverse rapeseed accessions, and several loci related to oleic acid content were identified. Furthermore, these loci were functionally characterized in Saccharomyces cerevisiae to assess their functions, and the promising candidate loci were validated using single nucleotide polymorphic markers in an independent inbred population. The results increased our understanding of fatty acid metabolism in B. napus. Moreover, these findings may assist in marker-based breeding efforts to improve the fatty acid composition and quality of B. napus oil.

14.
J Asian Nat Prod Res ; : 1-10, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31773971

RESUMO

Gramine can be intelligently and efficiently supplied with N, N-dimethylamino group and then reacted with the corresponding sulfonyl chlorides to synthesize N, N-dimethylarylsulfonamides. We herein designed and controlled synthesis of N, N-dimethylarylsulfonamide derivatives, and first reported the results of the nematicidal activity of 15 title compounds 3a-o against Meloidogyne incongnita in vitro, respectively. Among all of the title derivatives, compounds 3a, 3c, 3k, and 3o exhibited potent nematicidal activity with median lethal concentration (LC50) values ranging from 0.22 to 0.26 mg/L. Most noteworthy, N, N-dimethyl-4-methoxyphenylsulfonamide (3c) and N, N-dimethyl-8-quinolinesulfonamide (3o) showed the best promising and pronounced nematicidal activity, with LC50 values of 0.2381 and 0.2259 mg/L, respectively.

15.
Nanotechnology ; 2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31778980

RESUMO

Carbon nanotubes are outstanding reinforcements owing to their unparallel strength, while their effects on the copper nanowire are still not fully understood, hampering their broad applications. Herein, we have investigated the tensile behaviors of the nanocomposite-wire of carbon nanotube-copper using molecular dynamic simulations. For the nanocomposite, both the coated and embedded carbon nanotubes increase the Young's modulus, fracture stress and toughness of the copper nanowire. A reinforcement of over fivefold in both yield strength (5.3 times) and toughness (5.1 times) has been achieved when the carbon nanotubes are coated on the copper nanowires, as well as 1.7 times in the Young's modulus. Higher temperatures and lower loading rates reduce the reinforcement.

16.
Cell Rep ; 29(8): 2217-2228.e5, 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31747596

RESUMO

Since 2013, H7N9 avian influenza viruses (AIVs) have caused more than 1,600 human infections, posing a threat to public health. An emerging concern is whether H7N9 AIVs will cause pandemics among humans. Molecular analysis of hemagglutinin (HA), which is a critical determinant of interspecies transmission, shows that the current H7N9 AIVs are still dual-receptor tropic, indicating limited human-to-human transmission potency. Mutagenesis and structural studies reveal that a G186V substitution is sufficient for H7N9 AIVs to acquire human receptor-binding capacity, and a Q226L substitution would favor binding to both avian and human receptors only when paired with A138/V186/P221 hydrophobic residues. These data suggest a different evolutionary route of H7N9 viruses compared to other AIV-subtype HAs.

17.
Opt Express ; 27(21): 30009-30019, 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31684255

RESUMO

Simultaneously controlling the spatial distribution of multiple parameters of a light field in a three-dimensional (3D) space is highly desirable because of its prominent applications in the areas of optical imaging, microscopy, and manipulation. Phase-only encoding techniques that use a phase-only computer-generated hologram (CGH) to reshape and efficiently reconstruct target fields have fostered substantial interests. In this paper, we propose a convenient encoding method to construct vector fields with spatially structured multiple parameters in a 3D space by integrating the Fourier phase-only encoding technique into a modified Sagnac polarization conversion system. Without spatial filtering, various vector fields are constructed instantly at the image plane. Furthermore, utilizing a macro-pixel encoding approach, we demonstrate the possibility of a simultaneous and an independent construction of multiple vector fields in a 3D space. This method can also benefit the design of a metasurface to implement a polarization hologram.

18.
Small ; 15(50): e1904248, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31724823

RESUMO

Switchable structured adhesion on rough surfaces is highly desired for a wide range of applications. Combing the advantages of gecko seta and creeper root, a switchable fibrillar adhesive composed of polyurethane (PU) as the backing layer and graphene/shape memory polymer (GSMP) as the pillar array is developed. The photothermal effect of graphene (under UV irradiation) changes GSMP micropillars into the viscoelastic state, allowing easy and intimate contact on surfaces with a wide range of roughness. By controlling the phase state of GSMP via UV irradiation during detachment, the GSMP micropillar array can be switched between the robust-adhesion state (UV off) and low-adhesion state (UV on). The state of GSMP micropillars determines the adhesion force capacity and the stress distribution at the detaching interface, and therefore the adhesion performance. The PU-GSMP adhesive achieves large adhesion strength (278 kPa), high switching ratio (29), and fast switching (10 s) at the same time. The results suggest a design principle for bioinspired structured adhesives, especially for reversible adhesion on surfaces with a wide range of roughness.

19.
Micromachines (Basel) ; 10(11)2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31739492

RESUMO

Droplet microfluidic technology achieves precise manipulation of droplet behaviors by designing and controlling the flow and interaction of various incompatible fluids. The electric field provides a non-contact, pollution-free, designable and promising method for droplet microfluidics. Since the droplet behaviors in many industrial and biological applications occur on the contact surface and the properties of droplets and the surrounding environment are not consistent, it is essential to understand fundamentally the sessile droplet motion and deformation under various conditions. This paper reports a technique using the pin-plate electrode to generate non-uniform dielectrophoresis (DEP) force to control sessile droplets on hydrophobic surfaces. The electrohydrodynamics phenomena of the droplet motion and deformation are simulated using the phase-field method. It is found that the droplet moves along the substrate surface to the direction of higher electric field strength, and is accompanied with a certain offset displacement. In addition, the effect of pin electric potentials, surface contact angles and droplet volumes on the droplet motion and deformation are also studied and compared. The results show that higher potentials, more hydrophobic surfaces and larger droplet volumes exhibit greater droplet horizontal displacement and offset displacement. But for the droplet vertical displacement, it is found that during the first revert process, the release of the surface tension can make the droplet with low potentials, small contact angles or small droplet volumes span from negative to positive. These results will be helpful for future operations encountered in sessile droplets under non-uniform electric fields towards the droplet microfluidics applications.

20.
Dalton Trans ; 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31761912

RESUMO

Reactions of metalloligands MIII(notpH3) (M = Fe, Co and notpH6 = 1,4,7-triazacyclononane-1,4,7-triyl-tris(methylenephosphonic acid)) with Zn(OAc)2 under hydrothermal conditions resulted in new metal phosphonates Zn2Fe(notp)Cl(H2O) (1) and ZnCo(notpH)(H2O)·2H2O (2). They crystallize in polar space groups P63 (for 1) and Pca21 (for 2), respectively, and exhibit layer structures in which the inorganic layers are separated by the organic groups of the notp ligands. However, the layer topologies of the two compounds are quite different. In 1, the layer contains 6-membered rings composed of one {FeN3O3} octahedron, one {Zn1O3Cl}, one {Zn2O4} and three {PO3C} tetrahedra via corner-sharing connections, while in 2, the layer contains 10-membered rings composed of two {CoO3N3} octahedra, three {ZnO4} and five {PO3C} tetrahedra via vertex-sharing connections. Dielectric measurements on single crystals of 2 confirmed the presence of high dielectric anisotropy. Proton conductivity measurements revealed that the proton conduction is more favourable in 2 due to the presence of a continuous hydrogen bond network in this compound.

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