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1.
Clin Anat ; 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38651194

RESUMEN

As the cornerstone of medicine, the development of anatomy is related to many disciplines and fields and has received extensive attention from researchers. How to integrate and grasp the cutting-edge information in this field quickly is a challenge for researchers, so the aim of this study is to analyze research in anatomy using CiteSpace and VOSviewer in order to identify research hotspots and future directions. To offer a fresh viewpoint for assessing the academic influences of researchers, nations, or institutions on anatomy, and to examine the development of hotspots in anatomical study and to forecast future trends. A total of 4637 anatomy-related publications from 2013 to 2023 were collected from Web of Science Core Collection databases. Their temporal distribution, spatial distribution, cited authors, co-cited journals, keywords, and disciplinary connections in the literature were analyzed using CiteSpace and VOSviewer, and a knowledge graph was constructed. The temporal distribution shows a general fluctuation in the amount of literature published from 2013 to 2023. In spatial distribution, the total number of published articles was highest in the United States, the United Kingdom, and China, the United States leading. Tubbs, Rhoton, Iwanaga, and LaPrade are important authors in anatomy. Clinical Anatomy, Surgical and Radiologic Anatomy, and Journal of Anatomy were the most highly cited journals. Analysis of keywords and citation emergence showed that the research hotspots and trends in anatomy focused mainly on anatomy education, digital technology, and surgical management. At the same time, anatomy showed a trend toward multidisciplinary crossover, developing closer relationships with molecular biology, immunology, and clinical medicine. Current research in anatomy focuses on innovative reform of the educational model and the application and promotion of digital technology. Also, multidisciplinary cross-fertilization is an inevitable trend for the future development of anatomy.

2.
Langmuir ; 39(41): 14791-14799, 2023 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-37796482

RESUMEN

Two-dimensional ferroelectric monolayer materials with reversible spontaneous polarization provide more regulatory dimensions for their relevant van der Waals heterostructures. Using first-principles calculations, we construct the C2N/In2Se3 bilayer heterostructure and study its physical properties as well as the effects of E-field and strain. The results indicate that the intrinsic polarization of the component In2Se3 monoalyer can significantly adjust the electronic properties of the C2N/In2Se3 heterobilayer. When the polarization of the In2Se3 monolayer points to the interface (up-In2Se3), the C2N/In2Se3 bilayer behaves as the type-I indirect band gap heterostructure, while it transforms to the type-II direct band gap heterostructure after reversing the polarization of the In2Se3 monolayer (dp-In2Se3). Furthermore, the two C2N/In2Se3 heterostructures both have enhanced optical absorption in the visible region than the isolated In2Se3 and C2N monolayers. More importantly, the external electric field and strain can easily regulate the electronic properties of the C2N/In2Se3 heterostructures. The power conversion efficiency (PCE) of the type-II C2N/dp-In2Se3 heterostructure is 8.16%, and the electric field of 0.1 V/Å and the strain of -2% can transform the C2N/up-In2Se3 heterostructure into type-II one, conducive to the high PCE up to 24.03 and 24%, respectively. Our proposed C2N/In2Se3 heterostructure is promising in future luminescent and photovoltaic fields, and our findings also provide a strategy for functionalizing 2D monolayer materials by the intrinsic polarization property of ferroelectric materials.

3.
Langmuir ; 39(42): 15142-15151, 2023 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-37812576

RESUMEN

In this study, DFT calculations are used to analyze the adsorption of industrial waste gases (NO2, SO2, H2S, and NH3) on WSe2 monolayers. The adsorption energy, energy band, density of states, charge transfer, and recovery time of the adsorption structures between the target gas molecules and the Os-doped WSe2 are studied. Compared with pure WSe2 monolayer, Os surface bonding doping WSe2 (Os-modified WSe2) and Os doping with Se vacancy of WSe2 (Os-embedded WSe2) exhibit improved gas molecule adsorption ability. Among them, the adsorption energy of the Os-modified WSe2 monolayer on NO2, SO2, H2S, and NH3 is greater than that of the WSe2 monolayer. At the same time, it is proved that the Os-embedded WSe2 can be used as a gas sensor for H2S and NH3 gas molecules at a high temperature.

4.
Langmuir ; 39(31): 10769-10778, 2023 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-37491738

RESUMEN

Building two-dimensional (2D) vertical van der Waals heterostructures (vdWHs) is one of the effective methods to regulate the properties of single 2D materials. In this paper, we stack the hexagonal boron nitride (h-BN) monolayer (ML) on the SnSe2 ML to construct the stable h-BN/SnSe2 vdWH, of which the crystal and electronic structures, together with the optical properties, are also analyzed by the first-principles calculations. The results show that the h-BN/SnSe2 vdWH belongs to a type-I heterostructure with an indirect bandgap of 1.33 eV, in which the valence band maximum and conduction band minimum are both determined by the component SnSe2 ML. Interestingly, the h-BN/SnSe2 vdWH under the tensile strain or electric field undergoes the transitions both from type-I to type-II heterostructure and from the indirect to direct bandgap semiconductor. In addition, the carrier mobility of the h-BN/SnSe2 heterostructure has a significant enhancement relative to that of the SnSe2 ML, up to 104 cm2 V-1 s-1. Meanwhile, the h-BN/SnSe2 heterostructure presents the superb optical absorption and unique type-II hyperbolic property. Our findings will broaden the potential applications of SnSe2 ML and provide theoretical guidance for the related experimental studies.

5.
Phys Chem Chem Phys ; 25(43): 29594-29602, 2023 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-37877368

RESUMEN

Due to the asymmetrical structure in the vertical direction, Janus two-dimensional (2D) monolayer (ML) materials possess some unique physical properties, holding great promise for nanoscale devices. In this paper, based on the newly discovered MoA2Z4 (A = Si, Ge; Z = N, P, As) ML, we propose a class of 2D Janus MoAZ3H ML materials with good stability and excellent mechanical properties using first-principles calculations. We demonstrate that the novel Janus MoAZ3H ML materials are all semiconductors with bandgaps ranging from 0.69 to 2.44 eV, giving rise to good absorption in the visible light region. Especially, both MoSiN3H and MoGeN3H MLs can be used as catalysts for producing hydrogen through water splitting. This catalytic property is much more efficient than that of the MoA2Z4 ML, attributed to the intrinsic electric field induced by the vertical asymmetry effectively separating electrons and holes. More importantly, the carrier mobility of the MoAZ3H ML is up to 103-104 cm2 V-1 s-1 due to the large elastic modulus or small effective mass. Additionally, the electronic properties of the MoAZ3H ML can be easily tuned by strain. Our results suggest a new strategy for designing novel 2D Janus materials, which not only expands the members in the 2D MA2Z4-based Janus family, but also provide candidates with excellent performances in photovoltaic and catalytic fields.

6.
Plant Dis ; 107(11): 3506-3516, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37157097

RESUMEN

Xanthomonas fragariae (X. fragariae) is the causal agent of angular leaf spots (ALS) in strawberry plants. Recently, a study in China isolated X. fragariae strain YL19, which was observed to cause both typical ALS symptoms and dry cavity rot in strawberry crown tissue; this was the first X. fragariae strain to have both these effects in strawberry. In this study, from 2020 to 2022, we isolated 39 X. fragariae strains from diseased strawberries in different production areas in China. Multilocus sequence typing (MLST) and phylogenetic analysis showed that X. fragariae strain YLX21 was genetically different from YL19 and other strains. Tests indicated that YLX21 and YL19 had different pathogenicities toward strawberry leaves and stem crowns. YLX21 did not cause ALS symptoms, rarely caused dry cavity rot in strawberry crown after wound inoculation, and never caused dry cavity rot after spray inoculation, but it did cause severe ALS symptoms after spray inoculation. However, YL19 caused more severe symptoms in strawberry crowns under both conditions. Moreover, YL19 had a single polar flagellum, while YLX21 had no flagellum. Motility and chemotaxis assays showed that YLX21 had weaker motility than YL19, which may explain why YLX21 tended to multiply in situ within the strawberry leaf rather than migrate to other tissues, causing more severe ALS symptoms and mild crown rot symptoms. Taken together, the new strain YLX21 helped us reveal critical factors underlying the pathogenicity of X. fragariae and the mechanism by which dry cavity rot in strawberry crowns forms.


Asunto(s)
Fragaria , Xanthomonas , Fragaria/microbiología , Tipificación de Secuencias Multilocus , Filogenia , Virulencia , Xanthomonas/patogenicidad
7.
Plant Dis ; 107(11): 3542-3552, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37194211

RESUMEN

Xanthomonas fragariae usually causes angular leaf spot (ALS) of strawberry, a serious bacterial disease in many strawberry-producing regions worldwide. Recently, a new strain of X. fragariae (YL19) was isolated from strawberry in China and has been shown to cause dry cavity rot in strawberry crown. In this study, we constructed a green fluorescent protein (GFP)-labeled Xf YL19 (YL19-GFP) to visualize the infection process and pathogen colonization in strawberries. Foliar inoculation of YL19-GFP resulted in the pathogen migrating from the leaves to the crown, whereas dip inoculation of wounded crowns or roots resulted in the migration of bacteria from the crowns or roots to the leaves. These two invasion types both resulted in the systematic spread of YL19-GFP, but inoculation of a wounded crown was more harmful to the strawberry plant than foliar inoculation. Results increased our understanding of the systemic invasion of X. fragariae, and the resultant crown cavity caused by Xf YL19.


Asunto(s)
Fragaria , Xanthomonas , Fragaria/microbiología , China
8.
Mol Plant Microbe Interact ; 35(2): 170-173, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34645282

RESUMEN

Xanthomonas fragariae is a global quarantine pathogen, which typically inflicts angular leaf spots. In the present study, we report a new 4.11-Mb high-quality genome sequence of X. fragariae YL19. YL19 can cause the typical angular leaf spot symptoms on strawberry plants in China as well as crown infection pocket symptoms. This new symptom has not been reported in other X. fragariae. Compared with typical X. fragariae strains, including PD885, NBC2815, PD5205, Fap21, and Fap29, the genome and plasmid in YL19 were smaller in size, lacking 109 coding genes, and have more carbohydrate-active enzyme and secondary metabolism genes. The YL19 genome ought to clarify the molecular mechanisms of genome evolution, host adaptation, and pathological process of X. fragariae and help improve strawberry management strategies.[Formula: see text] Copyright © 2022 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.


Asunto(s)
Fragaria , Xanthomonas , Fragaria/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Análisis de Secuencia de ADN , Xanthomonas/genética
9.
Opt Express ; 30(13): 23102-23114, 2022 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-36224997

RESUMEN

The tunable angle-selective transparency of hyperbolic metamaterials consisting of various multilayers of Dirac semimetal and dielectric materials are theoretically and numerically studied in the terahertz range. Three stack configurations are considered: alternating, sandwiched, and disordered. It is found that the proposed structures exhibit strong optical angular selectivity induced by photonic topological transition for transverse magnetic waves. Interestingly, the topological transition frequency can be flexibly modulated by changing the Fermi energy, temperature, and the releasing time of the Dirac semimetal, as well as the thickness ratio of the dielectric and semimetal layers. It is also noticed that the angular optical transparency properties are independent of the order of the proposed structure even in alternating/disordered/random configurations if the total thickness ratio of the semimetal to dielectric are the same, which makes the properties particularly easy to realize experimentally. The proposed hyperbolic metamaterial structures present a promising opportunity for wavefront engineering, offering crucial properties for applications in private screens, optical detectors, and light manipulation.

10.
Cell Commun Signal ; 20(1): 125, 2022 08 18.
Artículo en Inglés | MEDLINE | ID: mdl-35982465

RESUMEN

BACKGROUND: Pyroptosis, especially microglial pyroptosis, may play an important role in central nervous system pathologies, including traumatic brain injury (TBI). Transplantation of mesenchymal stem cells (MSCs), such as human umbilical cord MSCs (hUMSCs), has been a focus of brain injury treatment. Recently, MSCs have been found to play a role in many diseases by regulating the pyroptosis pathway. However, the effect of MSC transplantation on pyroptosis following TBI remains unknown. Tumor necrosis factor α stimulated gene 6/protein (TSG-6), a potent anti-inflammatory factor expressed in many cell types including MSCs, plays an anti-inflammatory role in many diseases; however, the effect of TSG-6 secreted by MSCs on pyroptosis remains unclear. METHODS: Mice were subjected to controlled cortical impact injury in vivo. To assess the time course of pyroptosis after TBI, brains of TBI mice were collected at different time points. To study the effect of TSG-6 secreted by hUMSCs in regulating pyroptosis, normal hUMSCs, sh-TSG-6 hUMSCs, or different concentrations of rmTSG-6 were injected intracerebroventricularly into mice 4 h after TBI. Neurological deficits, double immunofluorescence staining, presence of inflammatory factors, cell apoptosis, and pyroptosis were assessed. In vitro, we investigated the anti-pyroptosis effects of hUMSCs and TSG-6 in a lipopolysaccharide/ATP-induced BV2 microglial pyroptosis model. RESULTS: In TBI mice, the co-localization of Iba-1 (marking microglia/macrophages) with NLRP3/Caspase-1 p20/GSDMD was distinctly observed at 48 h. In vivo, hUMSC transplantation or treatment with rmTSG-6 in TBI mice significantly improved neurological deficits, reduced inflammatory cytokine expression, and inhibited both NLRP3/Caspase-1 p20/GSDMD expression and microglial pyroptosis in the cerebral cortices of TBI mice. However, the therapeutic effect of hUMSCs on TBI mice was reduced by the inhibition of TSG-6 expression in hUMSCs. In vitro, lipopolysaccharide/ATP-induced BV2 microglial pyroptosis was inhibited by co-culture with hUMSCs or with rmTSG-6. However, the inhibitory effect of hUMSCs on BV2 microglial pyroptosis was significantly reduced by TSG-6-shRNA transfection. CONCLUSION: In TBI mice, microglial pyroptosis was observed. Both in vivo and in vitro, hUMSCs inhibited pyroptosis, particularly microglial pyroptosis, by regulating the NLRP3/Caspase-1/GSDMD signaling pathway via TSG-6. Video Abstract.


Asunto(s)
Lesiones Traumáticas del Encéfalo , Moléculas de Adhesión Celular/metabolismo , Células Madre Mesenquimatosas , Adenosina Trifosfato/metabolismo , Animales , Lesiones Traumáticas del Encéfalo/patología , Lesiones Traumáticas del Encéfalo/terapia , Caspasa 1/metabolismo , Humanos , Lipopolisacáridos/farmacología , Células Madre Mesenquimatosas/metabolismo , Ratones , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo
11.
Phys Chem Chem Phys ; 24(30): 18331-18339, 2022 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-35880664

RESUMEN

Graphene-based van der Waals (vdW) heterostructures have opened unprecedented opportunities for various device applications due to their rich functionalities and novel physical properties. Motivated by the successful synthesis of a MoSi2N4 monolayer (Science, 2020, 369, 670), in this work by means of first-principles calculations we construct and investigate the interfacial electronic properties of the graphene/MoSi2As4 vdW heterostructure, which is expected to be energetically favorable and stable. Our results show that the graphene/MoSi2As4 heterostructure forms an n-type Schottky contact with a low barrier of 0.12 eV, which is sensitive to the external electric field and the transformation from an n-type Schottky contact to a p-type one can be achieved at 0.2 V Å-1. The small effective masses and strong optical absorption intensity indicate that the graphene/MoSi2As4 heterostructure will have a high carrier mobility and can be applied to high-speed FET. Importantly, we also show that the opening band gap can be achieved in the graphene/BN/MoSi2As4 heterostructure and the type-I band alignment can transform into type-II under an external electric field of -0.2 V Å-1. These findings demonstrate that the graphene/MoSi2As4 heterostructure can be considered as a promising candidate for high-efficiency Schottky nanodevices.

12.
Phys Chem Chem Phys ; 24(36): 21674-21687, 2022 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-36069473

RESUMEN

The physical properties and potential applications of two-dimensional (2D) materials can be effectively modulated and enriched by constructing van der Waals heterostructures (VDWHs) with two or more 2D monolayer materials. In this work, by using first-principles calculations based on density functional theory (DFT), we have systematically investigated the structural, electronic and optical properties of four α-Se-based VDWHs, that is, α-Se/Ca(OH)2, α-Se/GaSe, α-Se/h-BN and α-Se/MoS2 VDWHs. The results show that both the band alignment and band gap of these four VDWHs can be effectively modulated by interlayer coupling, biaxial strain and an external electric field. Compared with interlayer coupling and biaxial strain, the external electric field can modulate the electronic properties of these VDWHs more significantly, which makes them exhibit more rich electronic properties. Interestingly, the optical property calculations revealed that both α-Se and the four α-Se-based VDWHs have intrinsic hyperbolic properties. In addition, compared with the individual components, the optical absorption of these four VDWHs in the visible and ultraviolet light regions is significantly enhanced. These results enrich the properties of selenene and selenene-based VDWHs and extend their potential applications in electronic and optoelectronic devices.

13.
Phys Chem Chem Phys ; 24(12): 7512-7520, 2022 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-35289820

RESUMEN

Elemental two-dimensional (2D) materials have attracted extraordinary interest compared with other 2D materials over the past few years. Fifteen elements from group IIIA to VIA have been discussed experimentally or theoretically for the formation of 2D monolayers, and the remaining few elements still need to be identified. Here, using first-principles calculations within density functional theory (DFT) and ab initio molecular dynamics simulations (AIMDs), we demonstrated that polonium can form stable 2D monolayers (MLs) with a 1T-MoS2-like structure. The band structure calculations revealed that polonium monolayers possess strong semiconducting properties with a band gap of ∼0.9 eV, and such semiconducting properties can well sustain up to a thickness of 4 MLs with a bandgap of ∼0.1 eV. We also found that polonium monolayers can be achieved through a spontaneous phase transition of ultrathin films with magic thicknesses, resulting in a weaker van der Waals interaction of ∼32 meV Å-2 between each three atomic layers. Also, the underlying physics comes from layered Peierls-like distortion driven by strong quantum size effects. Based on these intriguing findings, a suitable substrate on which the polonium monolayer can be grown through an epitaxial growth technique is proposed for further experiments. Our work not only extends completely the puzzle of elemental 2D monolayer materials from group IIIA to VIA, but also presents a new formation mechanism of 2D materials beyond the database of bulk materials with layered van der Waals interactions.

14.
Exp Cell Res ; 405(2): 112680, 2021 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-34090862

RESUMEN

Ferredoxin reductase (FDXR), a mitochondrial membrane-associated flavoprotein, is essential for electron transfer and modulates p53-dependent apoptosis in cancer cells.FDXR may be implicated in epidermal and sebocytic differentiation, but its explicit function in sebocytes remains to be elucidated. In the present study, immunohistochemistry revealed that FDXR expression was increased in sebaceous cells of acne lesions. FDXR, PPARγ, LXRα/ß, SREBP1 and Sox9 expression was incremental during sebocyte differentiation. FDXR overexpression induced by Ad-GFP-FDXR infection enhanced differentiation, reactive oxygen species (ROS), lipogenesis and PPARγ expression, and consequnently inhibited proliferation in SZ95 sebocytes. Flow cytometry showed that FDXR overexpression induced significant blockade of G2/M phase but had no effect on sub-G1 (apoptotic) sebocytes. Insulin-like growth factor-1 (IGF-1)-induced FDXR and PPARγ expression and lipogenesis were abolished by pretreatment with PI3K inhibitor LY294002. These results suggest that FDXR overexpression might promote differentiation and lipogenesis via ROS production and suppress proliferation via G2/S blockade in SZ95 sebocytes. IGF-1 could facilitate differentiation and lipogenesis through PI3K/Akt/FDXR pathway. FDXR could serve as a potential marker of advanced sebaceous differentiation, and its overexpression may be involved in the development of acne lesions.


Asunto(s)
Apoptosis/efectos de los fármacos , Ciclo Celular/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Ferredoxinas/farmacología , Lipogénesis/efectos de los fármacos , Respiración de la Célula/efectos de los fármacos , Células Epiteliales/efectos de los fármacos , Humanos
15.
Ecotoxicol Environ Saf ; 243: 113968, 2022 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-35981483

RESUMEN

Effects of vitamin C supplementation on the oral bioaccessibility of lead (Pb) present in contaminated soils were examined using a number of in vitro assays (PBET, SBRC, UBM and IVG). In the presence of vitamin C, an increase in Pb bioaccessibility was observed in the gastric phase by 1.3-fold (30.5%-85.5%) and in the intestinal phase by 3.1-fold (0.9%-58.9%). Lead mobilization was regulated by reductive dissolution of Fe(III) and sequestration of Pb on secondary Fe minerals. Sequential extraction by the Bureau Community of Reference (BCR) provided more evidence that reducible fraction and residual fraction were major contributor of gastric Pb bioaccessibility, as well as reduced fractions in intestinal Pb bioaccessibility. In addition, higher non-carcinogenic risks may occur based on target hazard quotient (THQ ≥ 1). For people exposed to Pb present in soil, the management of vitamin C supplements is of serious concern.


Asunto(s)
Contaminantes del Suelo , Ácido Ascórbico , Disponibilidad Biológica , Suplementos Dietéticos , Compuestos Férricos , Humanos , Plomo/toxicidad , Suelo , Contaminantes del Suelo/análisis
16.
Environ Sci Technol ; 55(2): 1319-1328, 2021 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-33377766

RESUMEN

Under anoxic conditions, the interactions between As-bearing ferrihydrite (Fh) and As(V)-reducing bacteria are known to cause Fh transformations and As mobilization. However, the impact of different types of organic matter (OM) on microbial As/Fe transformation in As-bearing Fh-organic associations remains unclear. In our study, we therefore exposed arsenate-adsorbed ferrihydrite, ferrihydrite-PGA (polygalacturonic acid), and ferrihydrite-HA (humic acid) complexes to two typical Fe(III)- and As(V)-reducing bacteria, and followed the fate of Fe and As in the solid and aqueous phases. Results show that PGA and HA promoted the reductive dissolution of Fh, resulting in 0.7-1.6 and 0.8-1.9 times more As release than in the OM-free Fh, respectively. This was achieved by higher cell numbers in the presence of PGA, and through Fe-reduction via electron-shuttling facilitated by HA. Arsenic-XAS results showed that the solid-phase arsenite fraction in Fh-PGA and Fh-HA was 15-19% and 27-28% higher than in pure Fh, respectively. The solid-associated arsenite fraction likely increased because PGA promoted cell growth and As(V) reduction, while HA provided electron shuttling compounds for direct microbial As(V)-reduction. Collectively, our findings demonstrate that As speciation and partitioning during microbial reduction of Fh-organic associations are strongly influenced by PGA and HA, as well as the strains' abilities to utilize electron-shuttling compounds.


Asunto(s)
Arsénico , Compuestos Férricos , Hierro , Oxidación-Reducción
17.
Plant Dis ; 2021 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-33622057

RESUMEN

Strawberry (Fragaria × ananassa Duch.) is an important fruit crop in China. Typical crown infection pockets symptoms were observed on the infected strawberry in Liaoning province, China (121°60'E, 38°90'N) in the autumn of 2017. The disease incidence was estimated to be around 5 to 10 %, but could reach 30 to 40 % in some heavily affected plastic tunnels. The infected plants early displayed water-soaked symptoms on the abaxial leaf surface and subsequently developed reddish-brown shaped stripes and coalesced lesions on the adaxial leaf surface around the main veins (Fig. 1-A, 1-B). Several variable-size (0.3-0.8 mm in diameter) pockets were observed inside the crown tissues after dissection (Fig. 1-C). The diseased plants rarely reached fruiting and were easily broken between the crown tissue and the stem, and would eventually die. To identify the causal agent of this disease, the several surface-disinfested infected main veins and crown tissues were individually ground in sterile water and plated on sucrose peptone agar(SPA) medium (Hayward 1960) with 10-fold serial dilutions and incubated at 25℃. A number of yellow colonies grew on the medium at the 10-4 dilution 7 days after plating (Fig. 1-D) in all specimens. The colonies were aerobic, yellow, viscous, smooth, and gram-negative, which is a typical characteristic of Xanthomonas. To confirm identity of the causal bacteria, 18 colonies selected randomly were subjected to polymerase chain reactions (PCR) for the amplification of the cpn60 (Sahin et al. 2010), gyrB, rpoD, and fyuA (C Manceau et al. 2011), respectively. The results showed that the 18 colonies are identical. The cpn60, gyrB, rpoD, and fyuA sequences of this isolate were deposited in GenBank with accession numbers MT513132.1, MW233896, MW233897, and MW233895, respectively. BLAST searches with sequences of this isolate cpn60, gyrB, rpoD, and fyuA revealed 97.7%, 96.4%, 97.8%, and 97.3% similarity with the corresponding sequences of X. fragariae strain NBC2815 (LT853880.1), respectively. The resulting concatenated data set of cpn60-gyrB-rpoD-fyuA was used to build a Multilocus Sequence Analysis (MLSA) by maximum likelihood criteria (Fig. 2). The cpn60-gyrB-rpoD-fyuA sequences of the isolate from Liaoning clustered in the clade containing the type strain of X. fragariae NBC2815, indicating that it belongs to X. fragariae. Thus, the bacterial strain from Liaoning was designated as X. fragariae strain YL19. To fulfill Koch's postulates, the base of leaf petioles of disease-free strawberry plants were syringe-infiltrated inoculated with bacterial suspension (2×108 CFU) prepared from colonies of X. fragariae YL19 washed from SPA plates. The inoculated and control (treated with sterile water) were placed in a chamber (25/20℃day/night,≥90% relative humidity(RH), 12/12 h photoperiod) for three months. After one month, water-soaked symptoms were observed in the crown tissues of all X. fragariae YL19-inoculated plants. Two months after inoculation, a significant crown pocket similarly to initial symptoms observed in the field was developed on all inoculated plants. No symptoms were observed in the control plants. The bacteria were re-isolated from the symptomatic leaves, petioles and crowns, and confirmed as X. fragariae YL19 by the above mentioned morphological and molecular analyses. Pathogenicity tests were conducted three times and the same results were obtained. It was reported that X. fragariae usually causes angular leaf spot, a serious bacterial disease in many strawberry production regions worldwide. The typical symptoms of angular leaf spot caused by X. fragariae include reddish-brown, irregular spots on the upper leaf surface, water-soaked lesions developed along leaf veins. Although angular leaf spot caused by X. fragariae has been reported in Tianjin and Taiwan province, China (Wang et al. 2017; Wu et al. 2020), there is no report about the symptoms that infection pockets on crowns caused by X. fragariae strain YL19 as described above. This result indicated that YL19 is different from the other two X. fragariae strains reported in China or the disease caused by YL19 could be a severe case of angular leaf spot and vascular decline or collapse in strawberry (Bradbury, 1977). . To the best of our knowledge, these results showed a previously unreported new strain YL19 of X. fragariae is the causal agent of crown infecton pocket in strawberry in China, it may lead to serious losses to the local strawberry industry. This report will assist in developing management measures for this disease promptly.

18.
BMC Gastroenterol ; 20(1): 66, 2020 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-32164541

RESUMEN

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is currently the most common cause of chronic liver disease nowadays. Changes in diet and lifestyle have led to a dramatic increase in the prevalence of NAFLD around the world. This meta-analysis is to investigate the efficacy of physical activity intervention on liver-specific endpoints in the population with NAFLD, including hepatic enzyme, serum lipid, glucose metabolism and intra-hepatic lipid. METHODS: PubMed and China National Knowledge Infrastructure (CNKI) databases were searched for randomized clinical trials of physical activity intervention on NAFLD patients through April 20th, 2019. Effect sizes were reported as standardized mean difference (SMD) and 95% confidence intervals (CI). Quality of included studies was assessed according to the Cochrane risk of bias tool. Meta-analyses were conducted using random-effect or fixed-effect models depending on the significance of heterogeneity. Subgroup analyses according to types and duration of physical activity were conducted to investigate clinical variability. RESULTS: Nine studies with a cumulative total of 951 participants met selection criteria. Physical activity was found associated with small reductions in hepatic enzyme parameters: ALT (SMD -0.17, 95% CI:-0.30 to - 0.05), AST (SMD -0.25, 95% CI: - 0.38, - 0.13) and GGT (SMD -0.22, 95% CI: - 0.36, - 0.08). Significant small improvements were also found in serum lipid parameters including TC (SMD = - 0.22, 95% CI: - 0.34, - 0.09), TG (SMD = - 0.18, 95% CI: - 0.31 to - 0.06) and LDL-C (SMD = - 0.26, 95% CI: - 0.39 to - 0.13). Significant improvement was also found in intra-hepatic lipid content (SMD = - 0.21, 95% CI: - 0.36 to - 0.06) There was no difference between physical intervention group and control group in HDL and three glucose metabolism parameters. Subgroup analysis suggested both aerobic exercise alone and resistance exercise alone can improve most liver function and longer period of exercise generally had better improvement effect. CONCLUSIONS: Our findings suggest that physical activity alone can only slightly improve hepatic enzyme levels, most serum lipid levels and intra-hepatic lipid content in non-diabetic patients with NAFLD.


Asunto(s)
Terapia por Ejercicio/métodos , Enfermedad del Hígado Graso no Alcohólico/terapia , Glucemia/metabolismo , HDL-Colesterol/sangre , Ejercicio Físico , Humanos , Metabolismo de los Lípidos , Lípidos/sangre , Hígado/enzimología , Hígado/metabolismo , Enfermedad del Hígado Graso no Alcohólico/sangre , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Ensayos Clínicos Controlados Aleatorios como Asunto , Entrenamiento de Fuerza
19.
Environ Sci Technol ; 54(7): 4432-4442, 2020 04 07.
Artículo en Inglés | MEDLINE | ID: mdl-32176848

RESUMEN

The importance of arsenic metabolism by gut microbiota has been evidenced in risk characterization from As exposures. In this study, we evaluated the metabolic potency of human gut microbiota toward As(V)-sorbed goethite and jarosite, presenting different behaviors of As release, and the solid-liquid transformation and partitioning. The release of As occurred mainly in the small intestinal phase for jarosite and in the colon phase for goethite, respectively. We found higher degree of As(V) and Fe(III) reduction by human gut microbiota in the colon digests of goethite than jarosite. Speciation analysis using high-performance liquid chromatography coupled with inductively coupled plasma mass spectrometry and X-ray absorption near-edge spectroscopy, revealed that 43.2% and 8.5% of total As was present as As(III) in the liquid and solid phase, respectively, after goethite incubation, whereas almost all generated As(III) was in the colon digests of jarosite. Therefore, As bioaccessibility in human gastrointestinal tract was predominantly contributed to Fe(III) dissolution in jarosite, and to microbial reduction of Fe(III) and As(V) in goethite. It expanded our knowledge on the role of Fe minerals in human health risk assessment associated with soil As exposures.


Asunto(s)
Arsénico , Microbioma Gastrointestinal , Compuestos de Hierro , Compuestos Férricos , Humanos , Minerales , Sulfatos
20.
Phys Chem Chem Phys ; 22(44): 25930-25935, 2020 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-33164002

RESUMEN

The physicochemical properties of TiO2 are largely dependent on the defects. Here, using first-principles calculations, we report a systematic investigation of the magnetic properties of Ti-defected rutile TiO2 systems. The results of our calculations show that the VTi concentration can significantly affect the size of the magnetism, and that the magnetism weakens with decreasing VTi concentration. Studies of phonon dispersion curves show that systems with lower VTi concentrations of 8.33% and 6.25% are kinetically stable. Further detailed calculations on the Ti11O24 system indicate that the magnetism mainly originates from four of the six nearest-neighbor O atoms to the Ti vacancy, but much less from the other two. The magnetic ground states are discussed, and the results show that for the Ti11O24 system, the ferromagnetic (FM) state of the four nearest-neighbor O atoms to the Ti vacancy is the magnetic ground state, and for the Ti22O48 system, the FM state of the two vacancies is the magnetic ground state. In addition, our calculations also indicate that the magnetic properties of Ti-defected TiO2 can be tuned via strain engineering. In general, this metal-defected TiO2 represents a novel kind of semiconductor. Research into the magnetic properties reported in this paper can enrich theoretical knowledge in this area and provide more potential candidates for TiO2-based materials.

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