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1.
Ying Yong Sheng Tai Xue Bao ; 32(3): 895-905, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33754555

RESUMO

To understand the growth responses of dryland wheat to different application rates of phosphorus fertilizer in different rainfall years, we examined root characteristics, spike number, yield and phosphate utilization. Results would help improve phosphate fertilizer use in dryland wheat production. We carried out a field experiment at the research station of Shanxi Agricultural University from 2012 to 2016. We examined the effects of four application rates of phosphorus (0, 75, 150 and 225 kg·hm-2 on root growth, phosphate utilization and yield formation of dryland wheat in different years with contrasting rainfall pattern. Compared with the treatment without phosphorus fertilization, phosphate application increased root surface area at all growth stages and root weight density in the 0-80 cm soil layer at jointing, anthesis, and maturity stages. Phosphate application significantly increased soil water consumption from jointing to anthesis, and total soil water consumption in the growing season. Phosphate application enhanced the amount of pre-anthesis phosphate translocation and phosphate accumulation of grain. Spike number, yield and water use efficiency were increased with 75, 150 and 225 kg P·hm-2 by 9.2% to 22.5%, 11.8% to 30.0%, and 2.1% to 12.1%, respectively. In the dry years, the application rates of 150 and 225 kg P·hm-2 in comparison to 75 kg P·hm-2 significantly increased root weight density and root surface area at all stages, soil water consumption from sowing to jointing and from jointing to anthesis, and total water consumption in the growing season. In comparison to the rate of 75 kg P·hm-2, 150 and 225 kg P·hm-2 increased soil water consumption from sowing to jointing by 7.3-8.7 mm, soil water consumption from jointing to anthesis by 15.6-18.1 mm, and total water consumption by 15.6-18.1 mm. Significant increase in the pre-anthesis phosphate translocation and phosphate accumulation in grain was higher under 150 and 225 kg P·hm-2 than that under 75 kg P·hm-2 in dry years. Furthermore, the two rates (150 and 225 kg P·hm-2) in dry years increased spike number by 9.3%-10.7% and yield by 11.9%-14.6%. The application rate of 150 kg P·hm-2 significantly improved phosphorus use efficiency by 20%-82% in comparison to other rates. In normal years, the rates of 150 and 225 kg P·hm-2 increased root surface area, root weight density at both anthesis and maturity compared with 75 kg P·hm-2. Soil water consumption from anthesis to maturity and total soil water consumption in the growing season were also increased by 1.2-15.0 and 3.8-23.1 mm, respectively. In addition, phosphorus accumulation in post-anthesis and phosphate accumulation in grain were increased in both 150 and 225 kg P·hm-2, which increased spike number by 1.4%-9.6% and yield by 3.5%-10.4%. The effects of phosphate application at the rate of 150 kg P·hm-2 were significantly different from 75 and 225 kg P·hm-2. In conclusion, phosphorus fertilizer application enhanced uptake of water and phosphate in dryland wheat at early and middle growth stages in dry years and at the late growth stage in normal years. Phosphorus application increased wheat yield mainly due to the increases of spike number. The application of 150 kg P·hm-2 is the best choice for high water and phosphorus fertilizer use efficiency and high yield in both dry and normal years.


Assuntos
Fertilizantes , Triticum , Irrigação Agrícola , Agricultura , Biomassa , Nitrogênio , Fósforo , Solo , Água
2.
Zhongguo Zhong Yao Za Zhi ; 46(2): 478-487, 2021 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-33645137

RESUMO

To systematically evaluate the efficacy and safety of Huaier Granules in the adjuvant treatment of primary liver cancer. The databases of CNKI, Wanfang, VIP, CBMdisc, PubMed, Cochrane Library and EMbase were searched by computer to screen out the randomized controlled trial on Huaier Granules combined with Western medicine in the treatment of primary liver cancer from the establishment of the databases to January 2020. Data extraction and quality evaluation were conducted for the included literature. Meta-analysis was conducted with RevMan 5.3 software, and evidence quality evaluation was conducted for the outcomes by GRADE profiler software. A total of 24 articles were included, with a total sample size of 2 664 cases. Meta-analysis showed that as compared with Western medicine alone, Huaier Granules combined with Western medicine could improve the objective remission rate(RR=1.38, 95%CI[1.26, 1.51], P<0.000 01), disease control rate(RR=1.29, 95%CI[1.10, 1.52], P=0.002) and 6-month survival rate(RR=1.20, 95%CI[1.10, 1.32], P<0.000 1), 1-year survival rate(RR=1.39, 95%CI[1.23, 1.58], P<0.000 01), 2-year survival rate(RR=1.95, 95%CI[1.28, 2.96], P=0.002), KPS score(MD=17.15, 95%CI[6.47, 27.83], P=0.002) and the improvement rate of KPS score(RR=2.02, 95%CI[1.47, 2.77], P<0.000 1), AFP decline rate(RR=1.40, 95%CI[1.20, 1.62], P<0.000 1), CD3~+(MD=17.34, 95%CI[9.28, 25.40], P<0.000 1), CD4~+(MD=8.62, 95%CI[1.59, 15.64], P=0.02), CD8~+(MD=1.95, 95%CI[-3.93, 7.82], P=0.52), CD4~+/CD8~+(MD=0.42, 95%CI[-0.33, 1.17], P=0.27); reduce the level of AFP(MD=-71.57, 95%CI[-80.42,-62.72], P<0.000 01), recurrence rate(RR=0.76, 95%CI[0.67, 0.85], P<0.000 01), and incidence of adverse reactions(RR=0.60, 95%CI[0.41, 0.89], P=0.01) in patients with primary liver cancer. According to the GRADE system, the evidence for outcome measures was low to very low. The results show that Huaier Granules have certain efficacy and high safety in adjuvant treatment of primary liver cancer, but its effect in reducing adverse reactions and improve immunity remains to be verified. Due to the poor quality of the included studies and evidences, the conclusions still need to be further verified by multi-center, large sample, and randomized double-blind controlled studies.


Assuntos
Medicamentos de Ervas Chinesas , Neoplasias Hepáticas , Adjuvantes Farmacêuticos , Misturas Complexas , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Trametes
3.
NPJ Vaccines ; 6(1): 20, 2021 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-33514743

RESUMO

The mosquito-borne Zika virus is an emerging pathogen from the Flavivirus genus for which there are no approved antivirals or vaccines. Using the clinically validated PDK-53 dengue virus vaccine strain as a backbone, we created a chimeric dengue/Zika virus, VacDZ, as a live attenuated vaccine candidate against Zika virus. VacDZ demonstrates key markers of attenuation: small plaque phenotype, temperature sensitivity, attenuation of neurovirulence in suckling mice, and attenuation of pathogenicity in interferon deficient adult AG129 mice. VacDZ may be administered as a traditional live virus vaccine, or as a DNA-launched vaccine that produces live VacDZ in vivo after delivery. Both vaccine formulations induce a protective immune response against Zika virus in AG129 mice, which includes neutralising antibodies and a strong Th1 response. This study demonstrates that VacDZ is a safe and effective vaccine candidate against Zika virus.

4.
Environ Pollut ; 271: 116362, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33387782

RESUMO

Atrazine (ATR) is one of the most commonly used herbicides that could directly impair the growth and health of organisms in mariculture areas and adversely affect human health through the food chain. This study investigated the contaminant occurrence, migration, and transformation of ATR and three of its chlorinated metabolites, namely deethylatrazine (DEA), deisopropylatrazine (DIA), and didealkylatrazine (DDA), in surface seawater, sediment, and aquatic organisms from the Xiangshan Harbor. ATR was detected in all samples, while DIA and DDA were only respectively detected in aquatic and seawater samples. The distribution of ATR and its metabolites presented different patterns depending on the geographic location and showed a higher level in the aquaculture area than that in the non-aquaculture area. The bioaccumulation of ATR in aquaculture organisms showed that benthic organisms, such as Ditrema, and Sinonovacula constricta (Sin), had increased levels. The ecological risks indicated that ATR posed medium or high risks to algae in the water phase of the study area. The microcosm experiment showed that the main fate of ATR in the simulated microenvironment was sedimentation, which followed the first-order kinetic equation. The ATR in the sediment could be enriched 3-5 times in Sin, and its major metabolites were DEA and DIA.


Assuntos
Atrazina , Herbicidas , Aquicultura , Baías , Herbicidas/análise , Humanos , Água do Mar
5.
Phytochemistry ; 182: 112597, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33341030

RESUMO

Seven pairs of undescribed enantiomeric bis-coumarins, (±)-dievodialetins A-G, were separated from the roots of Evodia lepta Merr. Two coumarin nuclei were linked via a 1,4-dimethyl4-vinylcyclohexene moiety in (±)-dievodialetins C-G. The structures of the undescribed compounds, including their absolute configurations were elucidated by spectroscopic analyses, X-ray diffraction, and computational calculations. In the biosynthetic pathways, these bis-coumarins were presumably derived from the precursors demethylsuberosin and 3-(3-methylbut-2-enyl)umbelliferone via a [4 + 2] Diels-Alder reaction. Besides, all compounds exhibited neuroprotective effects by inhibiting acetylcholinesterase (AChE) activity with IC50 values ranging from 7.3 to 12.1 nM and they also suppressed oxidative stress (MDA and SOD) and neuroinflammation (IL-1ß and IL-6).


Assuntos
Evodia , Rutaceae , Acetilcolinesterase/metabolismo , Inibidores da Colinesterase/farmacologia , Cumarínicos/farmacologia , Estrutura Molecular , Raízes de Plantas/metabolismo , Rutaceae/metabolismo
6.
J Chromatogr A ; 1636: 461794, 2021 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-33341433

RESUMO

A rapid, simple, and generic analytical method for the simultaneous determination of 140 undesirable low-weight pesticides and mycotoxins from different chemical classes in black tea was developed. The method involved swelling the sample in ammonium acetate buffer, extraction with acetonitrile-dimethyl sulfoxide, cleanup by dual dispersive solid-phase extraction (D-SPE) with the assistance of low-temperature centrifugation, and analysis by ultraperformance liquid chromatography coupled with electrospray ionization tandem mass spectrometry using multiple reaction monitoring mode. The interferences in the extract were eliminated by the combination of dual d-SPE using only C18 sorbent and anhydrous magnesium sulfate, which maintained the chromatographic column under the ideal condition for a long time and enabled satisfactory recoveries of hydrophobic and hydrophilic analytes simultaneously. Matrix-matched calibration curves were obtained for most target compounds with linear regression coefficients above 0.9900. The limits of quantification (LOQs) ranged within 0.5-10.0 µg/kg, which were usually sufficient to verify the compliance of products with legal tolerances. Satisfactory recoveries of 64.5%-138.1% were obtained in black ta samples with the relative standard deviation (RSD) values between 1.8 and 25.9%. The inter-day precision ranged within 2.2%-24.9%. For over 90% of the analytes, the recoveries were between 70% and 120%, with RSD values below 15.0%. The application of this method in routine monitoring programs can drastically reduce effort and time.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Micotoxinas/análise , Praguicidas/análise , Espectrometria de Massas em Tandem/métodos , Chá/química , Acetonitrilos/química , Tampões (Química) , Dimetil Sulfóxido/química , Reprodutibilidade dos Testes , Extração em Fase Sólida , Espectrometria de Massas por Ionização por Electrospray
7.
Plant Sci ; 302: 110699, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33288012

RESUMO

Abscisic acid-responsive element (ABRE)-binding factors (ABFs) are important transcription factors involved in various physiological processes in plants. Stomata are micro channels for water and gas exchange of plants. Previous researches have demonstrated that ABFs can modulate the stomatal development in some plants. However, little is known about stomata-related functions of ABFs in carrots. In our study, DcABF3, a gene encoding for ABF transcription factor, was isolated from carrot. The open reading frame of DcABF3 was 1329 bp, encoding 442 amino acids. Expression profiles of DcABF3 indicated that DcABF3 can respond to drought, salt or ABA treatment in carrots. Overexpressing DcABF3 in Arabidopsis led to the increase of stomatal density which caused severe water loss. Expression assay indicated that overexpression of DcABF3 caused high expression of stomatal development-related transcription factor genes, SPCH, FAMA, MUTE and SCRMs. Increased antioxidant enzyme activities and higher expression levels of stress-related genes were also found in transgenic lines after water deficit treatment. Changes in expression of ABA synthesis-related genes and AtABIs indicated the potential role of DcABF3 in ABA signaling pathway. Under the treatment of exogenous ABA, DcABF3-overexpression Arabidopsis seedlings exhibited increased root length and germination rate. Our findings demonstrated that heterologous overexpression of DcABF3 positively affected stomatal development and also reduced ABA sensitivity in transgenic Arabidopsis.

8.
Cell Res ; 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33262452

RESUMO

Structural principles underlying the composition and synergistic mechanisms of protective monoclonal antibody cocktails are poorly defined. Here, we exploited antibody cooperativity to develop a therapeutic antibody cocktail against SARS-CoV-2. On the basis of our previously identified humanized cross-neutralizing antibody H014, we systematically analyzed a fully human naive antibody library and rationally identified a potent neutralizing antibody partner, P17, which confers effective protection in animal model. Cryo-EM studies dissected the nature of the P17 epitope, which is SARS-CoV-2 specific and distinctly different from that of H014. High-resolution structure of the SARS-CoV-2 spike in complex with H014 and P17, together with functional investigations revealed that in a two-antibody cocktail, synergistic neutralization was achieved by S1 shielding and conformational locking, thereby blocking receptor attachment and viral membrane fusion, conferring high potency as well as robustness against viral mutation escape. Furthermore, cluster analysis identified a hypothetical 3rd antibody partner for further reinforcing the cocktail as pan-SARS-CoVs therapeutics.

9.
Cell Rep ; 33(5): 108342, 2020 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-33147462

RESUMO

Influenza A virus (IAV) infection stimulates a type I interferon (IFN-I) response in host cells that exerts antiviral effects by inducing the expression of hundreds of IFN-stimulated genes (ISGs). However, most ISGs are poorly studied for their roles in the infection of IAV. Herein, we demonstrate that SERTA domain containing 3 (SERTAD3) has a significant inhibitory effect on IAV replication in vitro. More importantly, Sertad3-/- mice develop more severe symptoms upon IAV infection. Mechanistically, we find SERTAD3 reduces IAV replication through interacting with viral polymerase basic protein 2 (PB2), polymerase basic protein 1 (PB1), and polymerase acidic protein (PA) to disrupt the formation of the RNA-dependent RNA polymerase (RdRp) complex. We further identify an 8-amino-acid peptide of SERTAD3 as a minimum interacting motif that can disrupt RdRp complex formation and inhibit IAV replication. Thus, our studies not only identify SERTAD3 as an antiviral ISG, but also provide the mechanism of potential application of SERTAD3-derived peptide in suppressing influenza replication.

10.
Protoplasma ; 2020 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-33111186

RESUMO

Carotenoids are liposoluble pigments found in plant chromoplasts that are responsible for the yellow, orange, and red colors of carrot taproots. Drought is one of the main stress factors affecting carrot growth. Carotenoids play important roles in drought resistance in higher plants. In the present work, the carotenoid contents in three different-colored carrot cultivars, 'Kurodagosun' (orange), 'Benhongjinshi' (red), and 'Qitouhuang' (yellow), were determined by ultra-high-performance liquid chromatography (UPLC) after 15% polyethylene glycol (PEG) 6000 treatment. Real-time fluorescence quantitative PCR (RT-qPCR) was then used to determine the expression levels of carotenoid synthesis- and degradation-related genes. Increases in ß-carotene content in 'Qitouhuang' taproots under drought stress were found to be related to the expression levels of DcPSY2 and DcLCYB. Increases in lutein and decreases in α-carotene content in 'Qitouhuang' and 'Kurodagosun' under PEG treatment may be related to the expression levels of DcCYP97A3, DcCHXE, and DcCHXB1. The expression levels of DcNCED1 and DcNCED2 in the three cultivars significantly increased, thus suggesting that NCED genes could respond to drought stress. Analysis of the growth status and carotenoid contents of carrots under PEG treatment indicated that the orange cultivar 'Kurodagosun' has better adaptability to drought stress than the other cultivars and that ß-carotene and lutein may be involved in the stress resistance process of carrot.

11.
Small ; 16(41): e2002435, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32954651

RESUMO

Infection with live-attenuated vaccines always inevitably induces side effects that reduce their safety. This study suggests a concept of magnetic virus produced by genetically modifying viral surfaces with Fe3 O4 nanoparticles (NPs) to control their tropisms. An iron-affinity peptide is designed to be displayed on the viral surface protein (VP1) of human enterovirus type 71 (EV71), a typical nonenveloped picornavirus, as the model. The modified EV71 can self-bind with Fe3 O4 NPs under physiological conditions, resulting in novel EV71-Fe3 O4 hybrid materials. This rationally engineered EV71 with Fe3 O4 retains its original biological infectivity, but its tropism can be precisely controlled by magnetism. Both in vitro and in vivo experiments demonstrate that EV71-Fe3 O4 can infect only a desired area within the limit of the applied magnetic field, which effectively reduces its pathological damage. More importantly, this characteristic of EV71 can be inherited due to the gene-induced coassembly of viruses and NPs. This achievement provides a proof of concept in virus vaccine improvement by a combination of gene modification and material incorporation, leading to great potential for biomedical developments.

12.
PeerJ ; 8: e9661, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32864209

RESUMO

Luffa is a kind of melon crop widely cultivated in temperate regions worldwide. Browning is one of the serious factors affecting the quality of Luffa. Therefore, the molecular mechanism of Luffa browning is of great significance to study. However, the molecular diversity of Luffa cultivars with different browning-resistant abilities has not been well elucidated. In our study, we used high-throughput sequencing to determine the transcriptome of two Luffa cylindrica cultivars '2D-2' and '35D-7'. A total of 115,099 unigenes were clustered, of which 22,607 were differentially expression genes (DEGs). Of these DEGs, 65 encoding polyphenol oxidase, peroxidase, or ascorbate peroxidase were further analyzed. The quantitative real-time PCR (RT-qPCR) data indicated that the expression levels of the LcPPO gene (Accession No.: Cluster-21832.13892) was significantly higher in '35D-7' compared with that in '2D-2'. Several POD genes (Accession No.: Cluster-21832.19847, Cluster-21832.30619 and Cluster-48491.2) were also upregulated. Analysis of the plantTFDB database indicated that some transcription factors such as WRKY gene family may also participate in the regulation of Luffa browning. The results indicated that the divergence of genes expression related to enzymatic reaction may lead to the different browning resistances of Luffa. Our study will provide a theoretical basis for breeding of browning-resistant Luffa.

13.
Cell ; 182(5): 1271-1283.e16, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32795413

RESUMO

There is an urgent need for vaccines against coronavirus disease 2019 (COVID-19) because of the ongoing SARS-CoV-2 pandemic. Among all approaches, a messenger RNA (mRNA)-based vaccine has emerged as a rapid and versatile platform to quickly respond to this challenge. Here, we developed a lipid nanoparticle-encapsulated mRNA (mRNA-LNP) encoding the receptor binding domain (RBD) of SARS-CoV-2 as a vaccine candidate (called ARCoV). Intramuscular immunization of ARCoV mRNA-LNP elicited robust neutralizing antibodies against SARS-CoV-2 as well as a Th1-biased cellular response in mice and non-human primates. Two doses of ARCoV immunization in mice conferred complete protection against the challenge of a SARS-CoV-2 mouse-adapted strain. Additionally, ARCoV is manufactured as a liquid formulation and can be stored at room temperature for at least 1 week. ARCoV is currently being evaluated in phase 1 clinical trials.


Assuntos
RNA Mensageiro/genética , RNA Viral/genética , Vacinas Sintéticas/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Sítios de Ligação , Chlorocebus aethiops , Infecções por Coronavirus/genética , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Feminino , Células HEK293 , Células HeLa , Humanos , Imunogenicidade da Vacina , Injeções Intramusculares , Macaca fascicularis , Masculino , Camundongos , Camundongos Endogâmicos ICR , Nanopartículas/química , RNA Mensageiro/metabolismo , RNA Viral/metabolismo , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo , Células Th1/imunologia , Potência de Vacina , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/genética , Células Vero , Vacinas Virais/administração & dosagem , Vacinas Virais/genética
14.
Eur J Pharm Sci ; 154: 105476, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32717430

RESUMO

Cooperation effect of 4-vinylbenzeneboronic acid (4-VPBA) and methacrylic acid (MAA) was first used to improve the affinity of molecularly imprinted polymer (MIP) for drug delivery. The MIP was prepared using capecitabine (CAP) as template, MAA as functional monomer, 4-VPBA as auxiliary monomer, and trimethylolpropane trimethacrylate as cross-linker. The preparation conditions of the MIPs were optimized by investigating the types of functional monomers, the types of cross-linkers, the ratio of MAA to 4-VPBA, and the ratio of crosslinker to monomer. The results showed that the as-prepared MIP had the maximum imprinting factor of 4.03, which revealed this material had a specific recognition effect on the template molecules. Experiments with in vitro release indicated that the imprinted material released CAP stably for more than 10 h, while the non-imprinted polymer (NIP) released CAP only 4 h. In addition, the pharmacokinetics results from rats showed that the MIP was significantly superior to the NIP and CAP commercial drugs, and the plasma concentration of CAP reached the plateau between 3.0 and 9.0 h. These findings may extend the applicability of noncovalent molecular imprinting, particularly to the cases where the target molecule containing a cis-dihydroxy structure.

15.
Cell Death Dis ; 11(7): 545, 2020 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-32683410

RESUMO

Skeletal muscle atrophy is one of the clinical symptoms of myotonic dystrophy type 1 (DM1). A decline in skeletal muscle regeneration is an important contributor to muscle atrophy. Skeletal muscle satellite cells (SSCs) drive skeletal muscle regeneration. Increased autophagy can reduce the proliferative capacity of SSCs, which plays an important role in the early regeneration of damaged skeletal muscle in DM1. Discovering new ways to restore SSC proliferation may aid in the identification of new therapeutic targets for the treatment of skeletal muscle atrophy in DM1. In the pathogenesis of DM1, muscleblind-like 1 (MBNL1) protein is generally considered to form nuclear RNA foci and disturb the RNA-splicing function. However, the role of MBNL1 in SSC proliferation in DM1 has not been reported. In this study, we obtained SSCs differentiated from normal DM1-04-induced pluripotent stem cells (iPSCs), DM1-03 iPSCs, and DM1-13-3 iPSCs edited by transcription activator-like (TAL) effector nucleases (TALENs) targeting CTG repeats, and primary SSCs to study the pathogenesis of DM1. DM1 SSC lines and primary SSCs showed decreased MBNL1 expression and elevated autophagy levels. However, DM1 SSCs edited by TALENs showed increased cytoplasmic distribution of MBNL1, reduced levels of autophagy, increased levels of phosphorylated mammalian target of rapamycin (mTOR), and improved proliferation rates. In addition, we confirmed that after MBNL1 overexpression, the proliferative capability of DM1 SSCs and the level of phosphorylated mTOR were enhanced, while the autophagy levels were decreased. Our data also demonstrated that the proliferative capability of DM1 SSCs was enhanced after autophagy was inhibited by overexpressing mTOR. Finally, treatment with rapamycin (an mTOR inhibitor) was shown to abolish the increased proliferation capability of DM1 SSCs due to MBNL1 overexpression. Taken together, these data suggest that MBNL1 reverses the proliferation defect of SSCs in DM1 by inhibiting autophagy via the mTOR pathway.

16.
Biomed Pharmacother ; 130: 110517, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32688141

RESUMO

The flower of Hibiscus syriacus Linn is a well-known traditional Chinese medicine (TCM) and health food in China, which has been used to treat dysentery, vaginal discharge, and hemorrhoids. In this study, five polyphenols (compounds 1-5) and five fatty acids (compounds 6-10) were isolated from the ethanol extract of the flower of H. syriacus. The isolated compounds were characterized by spectroscopic techniques. Polyphenols, an important type of natural product, have variety of biological activities. Here, we employed LPS or H2O2-treated SH-SY5Y cell models to test the neuroprotective effect of compounds 1-10. Results found compounds 1-5 (concentration range was around 20 µM on LPS model, concentration range was around 13 µM on H2O2 model), not compounds 6-10, exhibited neuroprotective effect in LPS or H2O2-treated SH-SY5Y cell. PCR analysis showed that compounds 1-5 can effectively improve the mRNA expression of synapse-related gene and neurotrophic factors (Syp, NGF and BDNF) in LPS-treated SH-SY5Y cell. In addition, compounds 1-5 decreased the levels of ROS and MDA and increased the activities of SOD, GSH-Px and CAT in LPS-treated SH-SY5Y cell. Furthermore, compounds 1-5 inhibited neuroinflammation (TNF-α, IL-1ß and IL-6) in LPS-treated SH-SY5Y cell. In conclusion, the polyphenols in the flower of H. syriacus could be a promising candidate for preventive effect of neuroinflammation.

17.
Protoplasma ; 257(6): 1507-1517, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32577829

RESUMO

Carrot is a root crop consumed worldwide and has great nutritional qualities. It is considered as one of the ten most important vegetable crops. Cytokinins are an essential class of the plant hormones that regulate many processes of plant growth. Till now, the effects of cytokinin, BAP, on lignin biosynthesis and related gene expression profiles in carrot taproot is unclear. In order to investigate the effect of applied BAP on lignin-related gene expression profiles, lignin accumulation, anatomical structures, and morphological characters in carrot taproots. Carrot roots were treated with different concentrations of BAP (0, 10, 20, and 30 mg L-1). The results showed that the application of BAP significantly increased plant length, shoot fresh weight, root fresh weight, and taproot diameter. In addition, BAP at 20 mg L-1 or 30 mg L-1 enhanced the average number of petioles. BAP treatment led to increased number and width of xylem vessels. The parenchyma cell numbers of pith were significantly induced in taproots treated with the BAP at a concentration of 30 mg L-1. BAP significantly upregulated most of the expression levels of lignin biosynthesis genes, caused elevated lignin accumulation in carrot taproots. Our results indicate that BAP may play important roles in growth development and lignification in carrot taproots. Our results provide a valuable database for more studies, which may focus on the regulation of root lignification via controlling cytokinin levels in carrot taproots.

19.
Sci Adv ; 6(6): eaax7989, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32076641

RESUMO

Mosquito-borne flaviviruses infect both mammals and mosquitoes. RNA interference (RNAi) has been demonstrated as an anti-flavivirus mechanism in mosquitoes; however, whether and how flaviviruses induce and antagonize RNAi-mediated antiviral immunity in mammals remains unknown. We show that the nonstructural protein NS2A of dengue virus-2 (DENV2) act as a viral suppressor of RNAi (VSR). When NS2A-mediated RNAi suppression was disabled, the resulting mutant DENV2 induced Dicer-dependent production of abundant DENV2-derived siRNAs in differentiated mammalian cells. VSR-disabled DENV2 showed severe replication defects in mosquito and mammalian cells and in mice that were rescued by RNAi deficiency. Moreover, NS2As of multiple flaviviruses act as VSRs in vitro and during viral infection in both organisms. Overall, our findings demonstrate that antiviral RNAi can be induced by flavivirus, while flavivirus uses NS2A as a bona fide VSR to evade RNAi in mammals and mosquitoes, highlighting the importance of RNAi in flaviviral vector-host life cycles.


Assuntos
Culicidae/virologia , Infecções por Flavivirus/genética , Infecções por Flavivirus/virologia , Flavivirus/fisiologia , Interações Hospedeiro-Patógeno/genética , Interferência de RNA , Animais , Infecções por Flavivirus/transmissão , Regulação da Expressão Gênica , Mosquitos Vetores/virologia , Ribonuclease III/metabolismo , Proteínas não Estruturais Virais/metabolismo
20.
Protoplasma ; 257(3): 949-963, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31982943

RESUMO

Carotenoids are a group of natural pigments that are widely distributed in various plants. Carrots are plants rich in carotenoids and have fleshy roots with different colors. Carotenoid accumulation is a complex regulatory process with important guiding significance for carrot production. In this work, three carrot cultivars with different taproot colors, Hongxinqicun (orange), Benhongjinshi (red), and Tianzi (purple) were chosen as experimental materials to explore the molecular mechanism of carotenoid accumulation in carrot. Results showed that the three carotenoids, namely, α-carotene, ß-carotene, and lutein, had accumulated in orange carrot cultivar Hongxinqicun. Lycopene was only detected in the taproots of Benhongjinshi. Lutein was the main carotenoid in Tianzi. Comparison of the carotenoid contents in different tissues of carrot showed that leaf blade was the tissue with the highest carotenoid accumulation. Expression analysis of carotenoid biosynthesis genes and its correlation with carotenoid accumulation confirmed the regulatory role of structural genes in carrots. The high expression of five lycopene synthesis-related genes, DcPSY2, DcPDS, DcZDS1, DcCRT1, DcCRT2, and low expression of DcLCYE may result in the lycopene accumulation in Benhongjinshi. However, the function of certain genes, such as DcPSY1 that was lowly expressed in red carrot, requires further investigation. Our results provided potential insights into the mechanism of carotenoid accumulation in three carrot cultivars with different taproot colors.

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