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1.
Plant Physiol Biochem ; 146: 220-230, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31760343

RESUMO

Flowering time is regulated by biotic and abiotic stresses and affected by the ambient temperature. For chrysanthemum, a low ambient growth temperature can cause a flowering delay, which limits the annual commercial production. Therefore, it is important to improve the low-temperature flowering capability of chrysanthemum through genetic modifications. Here, we isolated a natural variation of a CRT/DRE-binding factor (CBF/DREB) 3 gene, CRAP2, from the Arabidopsis thaliana accession Condara (190AV) that encodes a stop codon at position 151 of the CBF3 protein. Unlike AtCBF3, the overexpression AtCRAP2 in Arabidopsis did not cause detectable growth retardation nor delayed flowering and it conferred cold tolerance. The cold-inducible expression of AtCRAP2 in chrysanthemum promoted flowering under short-day conditions with a low 15 °C nighttime temperature. RNA-sequencing of rd29A:AtCRAP2 and qRT-PCR assays of flowering time-related genes and AtCRAP2 expressed at an ambient temperature revealed that AtCRAP2 positively affected SOC1 and FTL3, thereby promoting flowering under low temperature stress and short-day conditions. These results indicate that DREB genes can be used in the genetic engineering of crop plants without accompanying negative effects by modifying the encoded proteins' C termini.

2.
Aging (Albany NY) ; 11(21): 9738-9766, 2019 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-31706255

RESUMO

BACKGROUND: Glioblastoma is the most common type of malignant brain tumor. Bioinformatics technology and structure biology were effectively and systematically used to identify specific targets in malignant tumors and screen potential drugs. RESULTS: GBM patients have higher AURKA and KDR mRNA expression compared with normal samples. Then, we identified a small molecular compound, ENMD-2076, could effectively inhibit Aurora kinase A and VEGFR-2 (encoded by KDR) activities. ENMD-2076 is predicted without toxic properties and also has absorption and gratifying brain/blood barrier penetration ability. Further results demonstrated that ENMD-2076 could significantly inhibit GBM cell lines proliferation and vitality, it also suppressed GBM cells migration and invasion. ENMD-2076 induced glioblastoma cell cycle arrest in G2-M phase and apoptosis by inhibiting PI3K/AKT/mTOR signaling pathways. Additionally, ENMD-2076 prolonged the median survival time of tumor-bearing rats and restrained growth rate of tumor volume in vivo. CONCLUSIONS: Our findings reveal that ENMD-2076 is a promising drug in dealing with glioblastoma and have a perspective application. METHODS: We show that AURKA and KDR genes are hub driver genes in glioblastoma with bioinformatics technology including WGCNA analysis, PPI network, GO, KEGG analysis and GSEA analysis. After identifying a compound via virtual screening analysis, further experiments were carried out to examine the anti-glioblastoma activities of the compound in vivo and in vitro.

3.
Anal Biochem ; 587: 113442, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31539524

RESUMO

To standardize the rice-specific quantification methods, the criteria of six genes of rice (gos9, PLD, SPS, RBE4, ppi-PPF and oriazain) were compared and evaluated by ddPCR. The results revealed that SPS, RBE4 and ppi-PPF were single copy genes per haploid genome and species specificity and stable among different rice cultivars, by employing Lectin gene of soybean as internal reference gene. The established ddPCR systems were precise and reliable with an absolute LOQ of 10-20 copies/reaction. Furthermore, the robustness of these three assays was verified by performing an intra-laboratory repeatability validation and the results showed that the three endogenous genes of rice could be quantitated repeatedly and precisely above the LOQ. These ddPCR methods can reliably quantified the GM content even if the content was low to 0.1%, which were much more reliable than the results from real-time PCR using the same primers and probes.

4.
PLoS One ; 14(6): e0218325, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31216306

RESUMO

Based on the high sensitivity and stable fluorescence of CdTe quantum dots (QDs) in conjunction with a specific DNA aptamer, the authors describe an aptamer-based fluorescence assay for the determination of Salmonella Typhimurium. The fluorescence detection and quantification of S. Typhimurium is based on a magnetic separation system, a combination of aptamer-coated Fe3O4 magnetic particles (Apt-MNPs) and QD-labeled ssDNA2 (complementary strand of the aptamer). Apt-MNPs are employed for the specific capture of S. Typhimurium. CdTe QD-labeled ssDNA2 was used as a signaling probe. Simply, the as-prepared CdTe QD-labeled ssDNA2 was first incubated with the Apt-MNPs to form the aptamer-ssDNA2 duplex. After the addition of S. Typhimurium, they could specifically bind the DNA aptamer, leading to cleavage of the aptamer-ssDNA2 duplex, accompanied by the release of CdTe QD-labeled DNA. Thus, an increased fluorescence signal can be achieved after magnetic removal of the Apt-MNPs. The fluorescence of CdTe QDs (λexc/em = 327/612 nm) increases linearly in the concentration range of 10 to 1010 cfu•mL-1, and the limit of detection is determined to be 1 cfu•mL-1. The detection process can be performed within 2 h and is successfully applied to the analysis of spiked food samples with good recoveries from 90% to 105%.


Assuntos
Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais , Infecções por Salmonella/diagnóstico , Salmonella typhimurium/isolamento & purificação , Compostos de Cádmio/química , Óxido Ferroso-Férrico/química , Fluorescência , Humanos , Pontos Quânticos/química , Infecções por Salmonella/microbiologia , Salmonella typhimurium/patogenicidade , Telúrio/química
5.
Anal Bioanal Chem ; 410(28): 7511-7521, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30317446

RESUMO

Alternariol monomethyl ether (AME) is one of the major Alternaria mycotoxins present in a wide range of fruits, vegetables, grains, and their products, and possesses the properties of mutagenicity and carcinogenicity. In this study, a simple, rapid, and highly sensitive colorimetric immunosensor based on magnetic nanoparticles (MNPs) was firstly developed for the detection of AME in fruit by nonaggregated gold nanoparticles (GNPs). AME-BSA-Fe3O4 MNP conjugates and free AME molecules in samples competitively bind with monoclonal antibody (mAb)-GNP conjugates. After magnetic separation, the UV absorbance of the nonaggregated GNP supernatant was measured directly. The absorption intensity was proportional to the concentration of AME in the sample. Carboxyl-group-modified AME, AME-bovine serum albumin (BSA) conjugates, anti-AME mAbs, AME-BSA-Fe3O4 MNP conjugates, and mAb-GNP conjugates were prepared and characterized. The effect of GNP sizes (16, 24, and 40 nm) on the colorimetric determination of AME was studied. Under optimized conditions, the limit of detection and the linear range for AME were 0.16 ng/mL and 0.08-0.48 ng/mL, respectively. Moreover, the colorimetric immunosensor developed has lower cross-reactivity with AME analogues. The recoveries of spiked fruits ranged from 80.6% to 90.7%. The colorimetric immunosensor developed provides a promising method for simple, rapid, highly sensitive, and highly specific detection of other mycotoxins in the field of food safety. Graphical abstract Competitive colorimetric immunosensor based on MNPs for the detection of AME by non-aggregated GNPs.


Assuntos
Citrus/química , Análise de Alimentos/métodos , Frutas/química , Lactonas/química , Prunus avium/química , Colorimetria , Imunoensaio , Estrutura Molecular
6.
PLoS One ; 12(3): e0173567, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28319152

RESUMO

Meat adulteration is a worldwide concern. In this paper, a new droplet digital PCR (ddPCR) method was developed for the quantitative determination of the presence of chicken in sheep and goat meat products. Meanwhile, a constant (multiplication factor) was introduced to transform the ratio of copy numbers to the proportion of meats. The presented ddPCR method was also proved to be more accurate (showing bias of less than 9% in the range from 5% to 80%) than real-time PCR, which has been widely used in this determination. The method exhibited good repeatability and stability in different thermal treatments and at ultra-high pressure. The relative standard deviation (RSD) values of 5% chicken content was less than 5.4% for ultra-high pressure or heat treatment. Moreover, we confirmed that different parts of meat had no effect on quantification accuracy of the ddPCR method. In contrast to real-time PCR, we examined the performance of ddPCR as a more precise, sensitive and stable analytical strategy to overcome potential problems of discrepancies in amplification efficiency discrepancy and to obtain the copy numbers directly without standard curves. The method and strategy developed in this study can be applied to quantify the presence and to confirm the absence of adulterants not only to sheep but also to other kinds of meat and meat products.


Assuntos
Contaminação de Alimentos/análise , Produtos da Carne/análise , Reação em Cadeia da Polimerase em Tempo Real/métodos , Animais , Aves/genética , Manipulação de Alimentos/métodos , Modelos Lineares , Mamíferos/genética , Proteína de Replicação A/genética , Reprodutibilidade dos Testes
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