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1.
Arch Virol ; 2021 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-34762150

RESUMO

Negeviruses are a group of insect-specific viruses that have a wide geographic distribution and broad host range. In recent years, nege-like viruses have been discovered in aphids of various genera of the family Aphididae, including Aphis, Rhopalosiphum, Sitobion, and Indomegoura. Here, we report the complete genome sequence of a nege-like virus isolated from Astegopteryx formosana aphids collected in Guangdong, China, which we have designated as "Astegopteryx formosana nege-like virus" (AFNLV). AFNLV has a genome length of 10,107 nt (excluding the polyA tail) and possesses the typical conserved domains of negeviruses. These include a viral methyltransferase, an S-adenosylmethionine-dependent methyltransferase, a viral helicase, and an RNA-dependent RNA polymerase (RdRP) domain in open reading frame 1 (ORF1), a DiSB-ORF2_chro domain in ORF2, and a SP24 domain in ORF3. The genome of AFNLV shares the highest nucleotide sequence identity (74.89%) with Wuhan house centipede virus, identified in a mixture of barley aphids. As clearly revealed by RdRP-based phylogenetic analysis, AFNLV, together with other negeviruses and nege-like viruses discovered in aphids, formed a distinct "unclassified clade" closely related to members of the proposed genus "Sandewavirus" and the family Kitaviridae. In addition, small interfering RNAs (siRNAs) derived from AFNLV did not exhibit typical characteristics of virus-derived siRNAs processed by the host RNAi-based antiviral pathway. However, the extremely high abundance of viral transcripts (average read coverage 73,403X) strongly suggested that AFNLV might actively replicate in the aphid host. AFNLV described in this study is the first nege-like virus discovered in aphids of the genus Astegopteryx, which will contribute to future study of the co-evolution of nege/nege-like viruses and their host aphids.

2.
Front Immunol ; 12: 710705, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34721379

RESUMO

Canine influenza virus (CIV) is an emerging virus that is associated with major hidden hazards to the canine population and public health. Until now, how canine uses its innate immunity to restrict CIV replication is seldomly investigated. Recently, studies on interferon-inducible transmembrane (IFITM) of several major hosts of influenza virus (human, chicken, duck, pig) indicated it can potently restrict the viral replication. Here, the gene locus of five previously annotated canine IFITM (caIFITM) genes was determined on chromosome 18 using multiple bioinformatics strategies, provisionally designated as caIFITM1, caIFITM2a, caIFITM2b, caIFITM3, and caIFITM5. An analysis on protein sequences between caIFITM and its homologs indicated they shared the same conserved amino acids important for the antiviral activity. Expression profile analysis showed that caIFITM was constitutively expressed in tissues and MDCK cell line. After treatment with interferon or infection with influenza virus, the expression level of caIFITM increased with different degrees in vitro. An animal challenge study demonstrated CIV infection resulted in upregulation of caIFITM in beagles. caIFITMs had a similar subcellular localization to their human homologs. caIFITM1 was present at the cell surface and caIFITM3 was present perinuclearly and colocalized with LAMP1-containing compartments. Finally, we generated A549 cell lines stably expressing caIFITM and challenged them with influenza virus. The result demonstrated caIFITM1, caIFITM2a, caIFITM2b, and caIFITM3 had a potent antiviral activity against influenza virus. Our study will help better understand the evolutional pattern of IFITM and its role in the host's defense against virus infection.

3.
Phys Chem Chem Phys ; 23(46): 26385-26391, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34792049

RESUMO

Effective charge separation is essential in plasmon-mediated photochemistry and is usually achieved by constructing plasmon-semiconductor interfaces, which is usually challenging. In this work, by monitoring the plasmon-mediated silver oxidation with in situ Raman spectroscopy, we demonstrate that the adsorbed thiophenol molecules could modulate the rate of photochemical reactions by tuning the charge separation at the plasmon-molecule interfaces. It is found that the thiophenol molecules with strong electron-withdrawing or donating functional groups could accelerate or decelerate the rate of plasmon-mediated silver oxidation, respectively. Owing to the easy tuning of the electronic structures of organic molecules via substitution, our method provides a versatile and convenient approach for the fine modulation of plasmon-mediated photochemical reactions.

4.
New Phytol ; 2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34812499

RESUMO

The development of viable pollen determines male fertility, and is crucial for reproduction in flowering plants. Phytochrome-Interacting Factor 3 (PIF3) acts as a central regulator of plant growth and development, but its relationship with pollen development has not been determined. Through genetic, histological and transcriptomic analyses, we identified an essential role for SlPIF3 in regulating tomato (Solanum lycopersicum) pollen development. Knocking out SlPIF3 using Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/Cas9 resulted in pollen mitosis I (PMI) arrest, and a failure to form viable pollen. We further demonstrated that both glutamate synthase 1 (SlGLT1) and cell wall invertase 9 (SlCWIN9), involved in auxin and sugar homeostasis, respectively, colocalized with SlPIF3 in the anthers and were directly regulated by SlPIF3. Knockout of either SlGLT1 or SlCWIN9 phenocopied the pollen phenotype of SlPIF3 knockout (Slpif3) lines. Slpif3 fertility was partially restored by exogenous auxin (IAA) in a dose-dependent manner. This study reveals a mechanism by which SlPIF3 regulates pollen development and highlights a new strategy for creating hormone-regulated genic male-sterile lines for tomato hybrid seed production.

5.
Chemistry ; 2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34812569

RESUMO

Surface plasmon can trigger or accelerate many photochemical reactions, especially useful in energy and environmental industries. Recently, molecular adsorption has been proved effective in modulating the plasmon-mediated photochemistry, however the realized chemical reactions are limited and the mechanism behind is still unclear. Herein, by using in situ dark-field optical microscopy, the plasmon-mediated oxidative etching of silver nanoparticles (Ag NPs), a typical hot-hole-driven reaction, is monitored continuously and quantitatively. The presence of thiol or thiophenol molecules is found essential in the silver oxidation. In addition, the rate of silver oxidation is modulated by the choice of different thiol or thiophenol molecules. Compared with the molecules having electron donating groups, the ones having electron accepting groups accelerate the silver oxidation dramatically. The thiol/thiophenol modulation is attributed to the modulation of the charge separation between the Ag NPs and the adsorbed thiol or thiophenol molecules. This work demonstrates the great potential of molecular adsorption in modulating the plasmon-mediated photochemistry, which will pave a new way for developing highly efficient plasmonic photocatalysts.

7.
Mol Ther Nucleic Acids ; 26: 1092-1106, 2021 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-34786213

RESUMO

The list of long non-coding RNAs (lncRNAs) that participate in the function of ovarian granulosa cells (GCs) is rapidly expanding, but the mechanisms through which lncRNAs regulate GC function are not yet fully understood. Here, we recognized a minimally expressed lncRNA RP4-545C24.1 (which we named DDGC) in GCs from patients with biochemical premature ovarian insufficiency (bPOI). We further explored the role of lncRNA DDGC in GC function and its contribution to the development of bPOI. Mechanistically, silencing DDGC downregulated RAD51 by competitively binding with miR-589-5p, and this resulted in significant inhibition of DNA damage repair capacity. In addition, decreased expression of DDGC promoted ubiquitin-mediated degradation of Wilms tumor 1 (WT1) protein through interactions with heat shock protein 90 (HSP90), which led to aberrant differentiation of GCs. Moreover, DDGC was able to ameliorate the etoposide-induced DNA damage and apoptosis in vivo. Taken together, these findings provide new insights into the contribution of lncRNAs in POI pathogenesis.

8.
J Am Coll Cardiol ; 78(14): e101, 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34593131
9.
Stroke Vasc Neurol ; 2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34645687

RESUMO

BACKGROUND AND PURPOSE: Signal transducer and activator of transcription 3 (STAT3) may contribute to the proinflammation in the central nervous system diseases by modulating the microglial responses. Thus, this study was intended to investigate the effect of STAT3 on microglia-dependent neuroinflammation and functional outcome after experimental subarachnoid haemorrhage (SAH). METHODS: The SAH model was established by endovascular perforation in the mouse. Real-time PCR (RtPCR) and western blot were used to examine the dynamic STAT3 signalling pathway responses after SAH. To clarify the role of the STAT3 signalling pathway in the microglia-dependent neuroinflammation after SAH, the microglia-specific STAT3 knockout (KO) mice were generated by the Cre-LoxP system. The neurological functions were assessed by Catwalk and Morris water maze tests. Neuronal loss after SAH was determined by immunohistochemistry staining. Microglial polarisation status after STAT3 KO was then examined by RtPCR and immunofluorescence. RESULTS: The STAT3 and Janus kinase-signal transducer 2 activated immediately with the upregulation and phosphorylation after SAH. Downstream factors and related mediators altered dynamically and accordingly. Microglial STAT3 deletion ameliorated the neurological impairment and alleviated the early neuronal loss after SAH. To investigate the underlying mechanism, we examined the microglial reaction after STAT3 KO. STAT3 deletion reversed the increase of microglia after SAH. Loss of STAT3 triggered the early morphological changes of microglia and primed microglia from M1 to M2 polarisation. Functionally, microglial STAT3 deletion suppressed the SAH-induced proinflammation and promoted the anti-inflammation in the early phase. CONCLUSIONS: STAT3 is closely related to the microglial polarisation transition and modulation of microglia-dependent neuroinflammation. Microglial STAT3 deletion improved neurological function and neuronal survival probably through promoting M2 polarisation and anti-inflammatory responses after SAH. STAT3 may serve as a promising therapeutic target to alleviate early brain injury after SAH.

10.
Front Vet Sci ; 8: 714249, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34660760

RESUMO

Enterocytozoon bieneusi is a microsporidian and zoonotic species. This study investigated the prevalence and distribution of E. bieneusi genotypes in farmed masked palm civets using nested PCR, as well as assessed their zoonotic potential by phylogenetic analysis of the ITS region of the rRNA region. Here, we collected 251 fecal specimens from farmed masked palm civets (Paguma larvata) from the Hainan Island, China. In total, 128 of 251 samples were positive for E. bieneusi, with an average infection rate of 51.0%. Seventeen genotypes were identified including 12 known genotypes-HNR-VI (n = 56), SHR1 (n = 45), SHW7 (n = 6), KIN-1 (n = 3), D (n = 3), New1 (n = 3), EbpC (n = 2), CHC5 (n = 1), CHG19 (n = 1), CHN4 (n = 1), EbpA (n = 1), and Henan-III (n = 1)-and five novel genotypes (HNPL-I to HNPL-II; one each). Phylogenetic analysis categorized these genotypes into two groups. Thirteen of them were members of the zoonotic group 1, and the remaining four genotypes were in group 12. This study has shown that the infection rates of E. bieneusi in masked palm civets from Hainan were relatively high and provide baseline data to control and prevent microsporidiosis in farm-related communities. Therefore, infections in masked palm civets with zoonotic genotypes D, EbpC, CHN4, EbpA, KIN-1, and Henan-III should be considered potential threats to public health.

11.
Comput Struct Biotechnol J ; 19: 5568-5577, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34712400

RESUMO

Severe fever with thrombocytopenia syndrome virus (SFTSV) is an emerging tick-borne virus that causes severe infection in humans characterized by an acute febrile illness with thrombocytopenia and hemorrhagic complications, and a mortality rate of up to 30%. Understanding on virus-host protein interactions may facilitate the identification of druggable antiviral targets. Herein, we utilized liquid chromatography-tandem mass spectrometry to characterize the SFTSV interactome in human embryonic kidney-derived permanent culture (HEK-293T) cells. We identified 445 host proteins that co-precipitated with the viral glycoprotein N, glycoprotein C, nucleoprotein, or nonstructural protein. A network of SFTSV-host protein interactions based on reduced viral fitness affected upon host factor down-regulation was then generated. Screening of the DrugBank database revealed numerous drug compounds that inhibited the prioritized host factors in this SFTSV interactome. Among these drug compounds, the clinically approved artenimol (an antimalarial) and omacetaxine mepesuccinate (a cephalotaxine) were found to exhibit anti-SFTSV activity in vitro. The higher selectivity of artenimol (71.83) than omacetaxine mepesuccinate (8.00) highlights artenimol's potential for further antiviral development. Mechanistic evaluation showed that artenimol interfered with the interaction between the SFTSV nucleoprotein and the host glucose-6-phosphate isomerase (GPI), and that omacetaxine mepesuccinate interfered with the interaction between the viral nucleoprotein with the host ribosomal protein L3 (RPL3). In summary, the novel interactomic data in this study revealed the virus-host protein interactions in SFTSV infection and facilitated the discovery of potential anti-SFTSV treatments.

12.
Adv Mater ; : e2106410, 2021 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-34715720

RESUMO

Humidity-based power generation that converts internal energy of water molecules into electricity is an emerging approach for harvesting clean energy from nature. Here we propose that intrinsic gradient within humidity field near sweating surfaces, such as river, soil or animal skins, is a promising power resource when integrated with liquid-infused nanofluidics. Specifically, we expose capillary-stabilized ionic liquid (IL, Omim+ Cl- ) film to above humidity field to create a sustained transmembrane water content difference, which enables asymmetric ion-diffusion across the nanoconfined fluidics, facilitating long-term electricity generation with the power density of ∼12.11 µW/cm2 . We attribute this high record to the nanoconfined IL that integrates van der Waals and electrostatic interactions to block movement of Omim+ clusters while allow for directional diffusion of moisture-liberated Cl- . This humidity gradient triggered large ion-diffusion flux for power generation indicates great potential of sweating surfaces considering that most of the earth is covered by water or soil. This article is protected by copyright. All rights reserved.

13.
Viruses ; 13(10)2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34696477

RESUMO

Severe fever with thrombocytopenia syndrome virus (SFTSV) is an emerging tick-borne bunyavirus in Asia that causes severe disease. Despite its clinical importance, treatment options for SFTSV infection remains limited. The SFTSV glycoprotein Gn plays a major role in mediating virus entry into host cells and is therefore a potential antiviral target. In this study, we employed an in silico structure-based strategy to design novel cyclic antiviral peptides that target the SFTSV glycoprotein Gn. Among the cyclic peptides, HKU-P1 potently neutralizes the SFTSV virion. Combinatorial treatment with HKU-P1 and the broad-spectrum viral RNA-dependent RNA polymerase inhibitor favipiravir exhibited synergistic antiviral effects in vitro. The in silico peptide design platform in this study may facilitate the generation of novel antiviral peptides for other emerging viruses.

14.
Viruses ; 13(10)2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34696478

RESUMO

RIG-I functions as a virus sensor that induces a cellular antiviral response. Although it has been investigated in other species, there have been no further studies to date on canine RIG-I against canine influenza virus (CIV). In the present study, we cloned the RIG-I gene of beagle dogs and characterized its expression, subcellular localization, antiviral response, and interactions with CIV proteins. RIG-I was highly expressed and mainly localized in the cytoplasm, with low levels detected in the nucleus. The results revealed that overexpression of the CARD domain of RIG-I and knockdown of RIG-I showed its ability to activate the RLR pathway and induced the expression of downstream interferon-stimulated genes. Moreover, overexpression of canine RIG-I suppressed the replication of CIV. The association between RIG-I and CIV was evaluated with the luciferase assay and by indirect immunofluorescence and bimolecular fluorescence complementation analyses. The results showed that CIV nonstructural protein 1 (NS1) can strongly suppress the RIG-I-mediated innate immune response, and the novel interactions between CIV matrix proteins (M1 and M2) and canine RIG-I were disclosed. These findings provide a basis for investigating the antiviral mechanism of canine RIG-I against CIV, which can lead to effective strategies for preventing CIV infection in dogs.

15.
Sci Rep ; 11(1): 21018, 2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-34697355

RESUMO

The discovery of new viruses is important for predicting their potential threats to the health of humans and other animals. A novel picornavirus was identified from oral, throat, and anal swab samples collected from belugas (Delphinapterus leucas), from Dalian Sun Asia Tourism Holding Co., China, between January and December 2018, using a metagenomics approach. The genome of this novel PicoV-HMU-1 strain was 8197 nucleotides (nt) in length, with a open reading frame (from 1091 to 8074 nt) that encoded a polyprotein precursor of 2328 amino acids. Moreover, the genomic length and GC content of PicoV-HMU-1 were within the ranges found in other picornaviruses, and the genome organization was also similar. Nevertheless, PicoV-HMU-1 had a lower amino acid identity and distinct host species compared with other members of the Picornaviridae family. Phylogenetic trees were constructed based on the P1 and 3D amino acid sequences of PicoV-HMU-1 along with representative members of the Picornaviridae family, which showed that PicoV-HMU-1 was related to unclassified bat picornaviruses groups. These findings suggest that the PicoV-HMU-1 strain represents a potentially novel genus of picornavirus. These data can enhance our understanding of the picornavirus genetic diversity and evolution.

16.
Neuroscience ; 480: 65-78, 2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34695538

RESUMO

Parkinson's disease (PD) is the second most frequently diagnosed neurodegenerative disease. The purpose of this study was to investigate the link between microbiota composition in important mucosal interfaces (oral, nasal, and intestinal) and PD. Sequencing was undertaken of the V4-V5 region of the 16S ribosomal RNA (rRNA) gene of the microbiome from the oral cavity, nasal cavity, and gut of 91 PD patients and 91 healthy controls. Significant differences were found in microbiota composition in the oral cavity and gut, but not the nasal cavity, between PD patients and healthy controls after adjusting for age, gender, and body mass index (BMI). More genera in the oral cavity were significantly positively correlated with clinical characteristics, such as the HAMA and HAMD rating scales. The taxa c_Clostridia, o_Clostridiales, and f_Ruminococcaceae in the gut microbiota were associated with weight and MMSE score. Furthermore, as a result of dysbiosis, there was an enrichment of ion channel-, oxidative phosphorylation-, and carbohydrate metabolism-related pathways in the oral cavity and glycolysis/gluconeogenesis- and propanoate metabolism-related pathways in the intestine. Changes in these pathways can influence metabolism and inflammation, thereby contributing to PD pathogenesis. In addition, several subnetworks containing differentially abundant microbiota in the oral cavity and gut samples from PD patients may regulate microbial composition and function in PD. Overall, our results indicate that oral and gut dysbiosis may affect PD progression and provide a basis for understanding the pathogenesis of PD and identifying potential therapeutic targets for the treatment of this disease.

17.
Nanoscale ; 13(36): 15151-15176, 2021 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-34486634

RESUMO

In the family of Janus nanomaterials, Janus nanosheets possess not only the advantages of Janus nanomaterials, but also the advantages of two-dimensional nanosheets, endowing them with many extraordinary properties. Therefore, Janus nanosheets have great potential in the fields of interfacial engineering, catalysis, and molecular recognition. This review summarizes and discusses the recent advances in both the preparation and applications of freestanding Janus nanosheets. After a short introduction to different types of Janus nanosheets, a variety of methods for preparing freestanding Janus nanosheets are introduced, including the surface reaction, interface reaction, emulsion reaction, self-assembly, and stripping of non-Janus nanosheets, as well as selective grafting of existing Janus nanosheets. Then, the wide applications of Janus nanosheets in the fields of emulsification, catalysis, polymer reinforcement, nanomotors, and molecular recognition are summarized in detail. Finally, a discussion on the remaining challenges and future perspectives in this field is included. This review will not only deepen the understanding of Janus nanosheets, but also benefit the designs and fabrications of extraordinary and multi-functional Janus nanosheets.

18.
Arch Virol ; 166(11): 3221-3224, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34515865

RESUMO

Equine hepacivirus (EqHV) is a newly discovered hepatitis C virus-like virus that can infect equines. EqHV strains circulating worldwide have been classified into subtypes 1-3. In previous studies, we detected the presence of EqHV strains of subtype 1 and 3 in China. To determine whether EqHV strains of subtype 2 are prevalent in China, serum samples were collected from 133 racehorses in Guangdong province in 2021 and were tested for EqHV RNA by RT-PCR, and the positive rate was 9% (12/133). Sequencing of the NS3 gene revealed that one field strain (GD2021) had a high degree of genetic similarity to EqHV strains of subtype 2. Subsequent genome sequencing and analysis demonstrated that strain GD2021 belongs to subtype 2. The present study enriches our knowledge about the genetic diversity of EqHV in China.


Assuntos
Hepacivirus/genética , Hepatite C/veterinária , Doenças dos Cavalos/virologia , Filogenia , Animais , China/epidemiologia , Genoma Viral , Hepacivirus/isolamento & purificação , Hepatite C/epidemiologia , Hepatite C/virologia , Doenças dos Cavalos/epidemiologia , Cavalos , Proteínas não Estruturais Virais/genética
19.
Adv Mater ; 33(43): e2105049, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34510587

RESUMO

Breaking the bottleneck of hydrogen oxidation/evolution reactions (HOR/HER) in alkaline media is of tremendous importance for the development of anion exchange membrane fuel cells/water electrolyzers. Atomically dispersed active sites are known to exhibit excellent activity and selectivity toward diverse catalytic reactions. Here, a class of unique Rh2 Sb nanocrystals with multiple nanobranches (denoted as Rh2 Sb NBs) and atomically dispersed Rh sites are reported as promising electrocatalysts for alkaline HOR/HER. Rh2 Sb NBs/C exhibits superior HER performance with a low overpotential and a small Tafel slope, outperforming both Rh NBs/C and commercial Pt/C. Significantly, Rh2 Sb NBs show outstanding HOR performance of which the HOR specific activity and mass activity are about 9.9 and 10.1 times to those of Rh NBs/C, and about 4.2 and 3.7 times to those of Pt/C, respectively. Strikingly, Rh2 Sb NBs can also exhibit excellent CO tolerance during HOR, whose activity can be largely maintained even at 100 ppm CO impurity. Density functional theory calculations reveal that the unsaturated Rh sites on Rh2 Sb NBs surface are crucial for the enhanced alkaline HER and HOR activities. This work provides a unique catalyst design for efficient hydrogen electrocatalysis, which is critical for the development of alkaline fuel cells and beyond.

20.
Chem Asian J ; 16(22): 3748-3753, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34549536

RESUMO

Bismuth-based compounds possess layered structures with a variety of stacking modes, endowing the compounds with diverse properties. As one type of bismuth oxysulfides, Bi9 O7.5 S6 nanocrystals has great applications in photodetection; however, the responsivity of bulky Bi9 O7.5 S6 is limited due to the poor charge separation. Herein, single-crystalline Bi9 O7.5 S6 thin nanosheets are successfully synthesized by using a solvothermal method. The thickness of the obtained Bi9 O7.5 S6 nanosheets is down to 15 nm and can be easily tuned by varying the reaction period. Moreover, the Bi9 O7.5 S6 nanosheets show strong light absorption in the visible and near infrared range, making it a promising candidate in optoelectronics. As a demonstration, the thin Bi9 O7.5 S6 nanosheets are used as active layer in an optoelectronic device, which exhibits sensitive photoelectric response to light in a wide range of 400-800 nm. The responsivity of the device reaches up to 1140 µA W-1 , and the performance of the device is stable after long-period illumination. This work demonstrates a great potential of the thin Bi9 O7.5 S6 nanosheets in optoelectronic devices, and these nanosheets may also be extended to various optoelectronic applications.

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