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1.
Metab Eng ; 61: 33-46, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32371091

RESUMO

In metabolic engineering, unbalanced microbial carbon distribution has long blocked the further improvement in yield and productivity of high-volume natural metabolites. Current studies mostly focus on regulating desired biosynthetic pathways, whereas few strategies are available to maximize L-threonine efficiently. Here, we present a strategy to guarantee the supply of reduced cofactors and actualize L-threonine maximization by regulating cellular carbon distribution in central metabolic pathways. A thermal switch system was designed and applied to divide the whole fermentation process into two stages: growth and production. This system could rebalance carbon substrates between pyruvate and oxaloacetate by controlling the heterogenous expression of pyruvate carboxylase and oxaloacetate decarboxylation that responds to temperature. The system was tested in an L-threonine producer Escherichia coli TWF001, and the resulting strain TWF106/pFT24rp overproduced L-threonine from glucose with 111.78% molar yield. The thermal switch system was then employed to switch off the L-alanine synthesis pathway, resulting in the highest L-threonine yield of 124.03%, which exceeds the best reported yield (87.88%) and the maximum available theoretical value of L-threonine production (122.47%). This inducer-free genetic circuit design can be also developed for other biosynthetic pathways to increase product conversion rates and shorten production cycles.

2.
ACS Synth Biol ; 9(5): 1201-1215, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32302096

RESUMO

Poly-3-hydroxybutyrate is an environmentally friendly polymer with many promising applications and can be produced in Escherichia coli cells after overexpressing the heterologous gene cluster phaCAB. In this study, we found that truncating the structure of lipopolysaccharide in E. coli can effectively enhance poly-3-hydroxybutyrate production. E. coli mutant strains WJW00, WJD00, and WJJ00 were constructed by deleting rfaD from E. coli strain W3110, DH5α, and JM109, respectively. Compared to the controls W3110/pDXW-8-phaCAB, DH5a/pDXW-8-phaCAB, and JM109/pDXW-8-phaCAB, the yield of poly-3-hydroxybutyrate in WJW00/pDXW-8-phaCAB, WJD00/pDXW-8-phaCAB, and WJJ00/pDXW-8-phaCAB cells increased by 200%, 81.5%, and 75.6%, respectively, and the conversion rate of glucose to poly-3-hydroxybutyrate was increased by ∼250%. Further analysis revealed that LPS truncation in E. coli rebalanced carbon and nitrogen metabolism, increased the levels of acetyl-CoA, γ-aminobutyric acid, NADPH, NADH, and ATP, and decreased the levels of organic acids and flagella, resulting in the high ratio of carbon to nitrogen. These metabolic changes in these E. coli mutants led to the significant increase of poly-3-hydroxybutyrate production.

3.
Sci Total Environ ; 725: 138419, 2020 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-32298899

RESUMO

Biochar and hydrochar have been served as attractive adsorbents for remediation of polluted water and soil, but it is lack of the long-term ageing effects on competitive adsorption of co-existing heavy metals by these carbonized materials. By this, corn stalk was used as carbon precursor to prepare biochar (500 °C) and hydrochar (200 °C). The single-metal and binary-metal Cd(II)/Cu(II) sorption were conducted on biochar and hydrochar before and after ageing using artificial accelerated ageing of 5% H2O2 treatment. The elemental analysis, BET, SEM, FTIR, XRD and Zeta potential were used to characterize the physicochemical properties of carbonized material samples. The results showed that oxidative ageing could increase O content and O-containing functional groups but decrease C content, metal content and aromaticity degree. Ageing hardly affected the SSA and crystallographic structures of biochar and hydrochar. The reduction of metal content in Aged-BC caused a decline of sorption capacity, indicating that cation exchange would be the predominant factor involved in biochar sorption for Cd(II) and Cu(II). As for hydrochar with more O-containing functional groups than biochar, the dominated sorption mechanism would be surface complexation, due to higher sorption capacity of Aged-HC with richer O-containing functional groups. In binary-metal system, the competitive sorption of Cd(II) and Cu(II) on biochar was observed obviously but that on hydrochar was limited. Ageing could increase the sorption capacity of Cd(II) in binary-metal system, resulting in alleviating competitive adsorption. The total sorption amount of Cd(II) and Cu(II) by biochar was markedly greater than that of hydrochar before or after ageing, suggesting that biochar can be still more capable than hydrochar for handling Cd(II) and Cu(II) in single-metal or binary-metal. These findings suggest us to consider the long-term effect on immobilization of co-existing heavy metals and alleviating competitive adsorption of carbonized materials as alternative amendment for contaminated sites.

4.
Microb Cell Fact ; 19(1): 46, 2020 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-32093713

RESUMO

BACKGROUND: Escherichia coli is an important strain for L-threonine production. Genetic switch is a ubiquitous regulatory tool for gene expression in prokaryotic cells. To sense and regulate intracellular or extracellular chemicals, bacteria evolve a variety of transcription factors. The key enzymes required for L-threonine biosynthesis in E. coli are encoded by the thr operon. The thr operon could coordinate expression of these genes when L-threonine is in short supply in the cell. RESULTS: The thrL leader regulatory elements were applied to regulate the expression of genes iclR, arcA, cpxR, gadE, fadR and pykF, while the threonine-activating promoters PcysH, PcysJ and PcysD were applied to regulate the expression of gene aspC, resulting in the increase of L-threonine production in an L-threonine producing E. coli strain TWF001. Firstly, different parts of the regulator thrL were inserted in the iclR regulator region in TWF001, and the best resulting strain TWF063 produced 16.34 g L-threonine from 40 g glucose after 30 h cultivation. Secondly, the gene aspC following different threonine-activating promoters was inserted into the chromosome of TWF063, and the best resulting strain TWF066 produced 17.56 g L-threonine from 40 g glucose after 30 h cultivation. Thirdly, the effect of expression regulation of arcA, cpxR, gadE, pykF and fadR was individually investigated on L-threonine production in TWF001. Finally, using TWF066 as the starting strain, the expression of genes arcA, cpxR, gadE, pykF and fadR was regulated individually or in combination to obtain the best strain for L-threonine production. The resulting strain TWF083, in which the expression of seven genes (iclR, aspC, arcA, cpxR, gadE, pykF, fadR and aspC) was regulated, produced 18.76 g L-threonine from 30 g glucose, 26.50 g L-threonine from 40 g glucose, or 26.93 g L-threonine from 50 g glucose after 30 h cultivation. In 48 h fed-batch fermentation, TWF083 could produce 116.62 g/L L-threonine with a yield of 0.486 g/g glucose and productivity of 2.43 g/L/h. CONCLUSION: The genetic engineering through the expression regulation of key genes is a better strategy than simple deletion of these genes to improve L-threonine production in E. coli. This strategy has little effect on the intracellular metabolism in the early stage of the growth but could increase L-threonine biosynthesis in the late stage.

5.
World Neurosurg ; 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31917305

RESUMO

This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal.

6.
Artigo em Inglês | MEDLINE | ID: mdl-31976571

RESUMO

Wild-type Escherichia coli usually does not accumulate l-threonine, but E. coli strain TWF001 could produce 30.35 g/L l-threonine after 23-H fed-batch fermentation. To understand the mechanism for the high yield of l-threonine production in TWF001, transcriptomic analyses of the TWF001 cell samples collected at the logarithmic and stationary phases were performed, using the wild-type E. coli strain W3110 as the control. Compared with W3110, 1739 and 2361 genes were differentially transcribed in the logarithmic and stationary phases, respectively. Most genes related to the biosynthesis of l-threonine were significantly upregulated. Some key genes related to the NAD(P)H regeneration were upregulated. Many genes relevant to glycolysis and TCA cycle were downregulated. The key genes involved in the l-threonine degradation were downregulated. The gene rhtA encoding the l-threonine exporter was upregulated, whereas the genes sstT and tdcC encoding the l-threonine importer were downregulated. The upregulated genes in the glutamate pathway might form an amino-providing loop, which is beneficial for the high yield of l-threonine production. Many genes encoding the 30S and 50S subunits of ribosomes were also upregulated. The findings are useful for gene engineering to increase l-threonine production in E. coli.

7.
Chembiochem ; 21(5): 650-655, 2020 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-31483539

RESUMO

The vibration of a cell membrane plays a key role in the regulation of cell shape and the behavior of cells. However, most existing approaches for the measurement of cell vibration require either exogenous modification or sophisticated techniques, and the main challenge lies in developing methods that can monitor membrane vibration of living cells directly. Herein, a noninvasive strategy based on ultrasmall quartz nanopipettes is introduced. With a tip size of less than 100 nm, nanopipettes can be spatially controlled for precision targeting of a specific location on the membrane of single living cells. Surprisingly, by employing a constant voltage, stable cyclic oscillations are observed from the continuous current versus time traces. The time-domain current can be decomposed into two basic waves: the high-frequency one indicates the local membrane vibration driven by the electro-osmotic flow from the nanopipette, whereas the low-frequency one indicates the natural frequency of the whole cell. This provides a simple but reliable method to test local and global membrane vibration of single living cells simultaneously with little damage, which provides a tool for the quantification of drugs, disease, or mutations of the cell structure.

8.
Food Chem ; 309: 125753, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31734009

RESUMO

The dispersion solid-phase microextraction (DSPE) combined with dispersion liquid-liquid microextraction (DLLME) was developed as a rapid, simple and effective pretreatment method for the determination of flavor enhancers (maltol, ethyl maltol, vanillin, methyl vanillin, ethyl vanillin) of ready-to-eat seafood products (dried squid, baked squid, fried fish, steamed abalone). Under the optimized DSPE-DLLME method, the developed method exhibited low limits of quantitation (0.20-0.50 µg g-1) and excellent linearity (R2 ≥ 0.995). The recoveries of flavor enhancers in the actual samples were 83.7%-114.9%. Compared with traditional pretreatment methods, the developed DSPE-DLLME method was rapid (17 min) and easy to determine the flavor enhancers by high performance liquid chromatography with photodiode array detector (HPLC-PDA). In the actual samples, creamy compounds such as vanillin, methyl vanillin and ethyl vanillin were hardly found. However, the flavor compounds produced by thermal reactions such as maltol (except for dried squid 3) and ethyl maltol were present in all samples.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Aromatizantes/análise , Alimentos Marinhos/análise , Benzaldeídos/análise , Aromatizantes/isolamento & purificação , Limite de Detecção , Microextração em Fase Líquida , Pironas/análise , Reprodutibilidade dos Testes , Extração em Fase Sólida
9.
Front Microbiol ; 10: 2520, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31798540

RESUMO

MraW is a 16S rRNA methyltransferase and plays a role in the fine-tuning of the ribosomal decoding center. It was recently found to contribute to the virulence of Staphylococcus aureus. In this study, we examined the function of MraW in Escherichia coli O157:H7 and found that the deletion of mraW led to decreased motility, flagellar production and DNA methylation. Whole-genome bisulfite sequencing showed a genome wide decrease of methylation of 336 genes and 219 promoters in the mraW mutant including flagellar genes. The methylation level of flagellar genes was confirmed by bisulfite PCR sequencing. Quantitative reverse transcription PCR results indicated that the transcription of these genes was also affected. MraW was furtherly observed to directly bind to the four flagellar gene sequences by electrophoretic mobility shift assay (EMSA). A common flexible motif in differentially methylated regions (DMRs) of promoters and coding regions of the four flagellar genes was identified. Reduced methylation was correlated with altered expression of 21 of the 24 genes tested. DNA methylation activity of MraW was confirmed by DNA methyltransferase activity assay in vitro and repressed by DNA methylation inhibitor 5-aza-2'-deoxycytidine (5-aza). In addition, the mraW mutant colonized poorer than wild type in mice. We also found that the expression of mraZ in the mraW mutant was increased confirming the antagonistic effect of mraW on mraZ. In conclusion, mraW was found to be a DNA methylase and have a wide-ranging effect on E. coli O157:H7 including motility and virulence in vivo via genome wide methylation and mraZ antagonism.

10.
Mikrochim Acta ; 186(11): 736, 2019 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-31673784

RESUMO

Pyrophosphate-modified carbon quantum dots (PP-CDs) are demonstrated to be a viable fluorescent nanoprobe for mercury(II) (Hg2+) detection. Hg2+ reacts with the pyrophosphate groups on the surface of PP-CDs to form a non-fluorescent complex. This results in quenching of the green fluorescence which has excitation/emission peaks at 400/513 nm. Static quenching is shown to be the dominant mechanism. The probe works in 0.1 µM to 1.4 µM Hg2+ concentration range, and the limit of detection is 2 nM. The PP-CDs were also used to visualize Hg2+ inside human hepatocyte LO2 cells. Graphical abstract Schematic representation of pyrophosphate-modified carbon quantum dots (CDs) for selective and sensitive fluorometric determination of mercury(II). Hg(II) quenches the blue fluorescence of the CDs, and glutathione restores it. The method was used to detect Hg(II) in spiked tap water and inside cells.

11.
Can J Microbiol ; 65(12): 922-929, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31525298

RESUMO

Blue light (BL) exerts an antimicrobial effect on pathogenic bacteria. It has been hypothesized that its bactericidal activity depends upon the generation of reactive oxygen species (such as anion superoxides) and the resultant cellular damage. However, some aspects of this hypothesis needed to be tested and investigated. Thus, the work conducted herein examined the molecular impact of BL treatment on Cronobacter sakazakii, an emerging foodborne pathogen. The results showed that BL exhibited an efficient bactericidal effect against C. sakazakii. Under a sublethal BL dose, both intracellular anion superoxides and malondialdehyde (a marker of oxidative stress) contents were increased gradually. Moreover, permeability of the outer membrane was increased by approximately 50%, indicating membrane damage. Further investigation revealed alterations to cellular fatty acid profiles, with a decrease and disappearance of unsaturated fatty acids, including C18:2, C16:1, and C18:1. These data indicate that bacterial lipids, especially unsaturated fatty acids, are important molecular targets of BL photo-oxidation. The transcriptional response of bacteria to BL was also studied, and it was found that three genes were upregulated, including genes encoding antioxidants. The current study contributes towards an improved understanding of the bactericidal mechanisms of BL and highlights the importance of lipid and membrane damage.


Assuntos
Cronobacter sakazakii/efeitos da radiação , Ácidos Graxos/efeitos da radiação , Luz , Estresse Oxidativo/efeitos da radiação , /metabolismo , Cronobacter sakazakii/genética , Cronobacter sakazakii/metabolismo , Ácidos Graxos/química , Genes Bacterianos/genética , Viabilidade Microbiana/efeitos da radiação , Espécies Reativas de Oxigênio/metabolismo , Regulação para Cima/efeitos da radiação
12.
Biotechnol Appl Biochem ; 66(6): 962-976, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31486127

RESUMO

Wild-type Escherichia coli MG1655 usually does not accumulate l-threonine. In this study, the effects of 13 genes related to the glucose uptake, glycolysis, TCA cycle, l-threonine biosynthesis, or their regulation on l-threonine accumulation in E. coli MG1655 were investigated. Sixteen E. coli mutant strains were constructed by chromosomal deletion or overexpression of one or more genes of rsd, ptsG, ptsH, ptsI, crr, galP, glk, iclR, and gltA; the plasmid pFW01-thrA*BC-rhtC harboring the key genes for l-threonine biosynthesis and secretion was introduced into these mutants. The analyses on cell growth, glucose consumption, and l-threonine production of these recombinant strains showed that most of these strains could accumulate l-threonine, and the highest yield was obtained in WMZ016/pFW01-thrA*BC-rhtC. WMZ016 was derived from MG1655 by deleting crr and iclR and enhancing the expression of gltA. WMZ016/pFW01-thrA*BC-rhtC could produce 17.98 g/L l-threonine with a yield of 0.346 g/g glucose, whereas the control strain MG1655/pFW01-thrA*BC-rhtC could only produce 0.68 g/L l-threonine. In addition, WMZ016/pFW01-thrA*BC-rhtC could tolerate the high concentration of glucose and produced no detectable by-products; therefore, it should be an ideal platform strain for further development. The results indicate that manipulating the glucose uptake and TCA cycle could efficiently increase l-threonine production in E. coli.

13.
Int J Clin Pharmacol Ther ; 57(10): 500-505, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31426902

RESUMO

OBJECTIVE: To evaluate the efficacy and safety of low-dose rituximab in the treatment of hematologic abnormalities in patients with connective tissue disease. MATERIALS AND METHODS: A total of 13 patients with connective tissue disease who did not respond to prednisolone and multiple immunosuppressive agents, or their disease recurred after treatment, were given 100 mg of rituximab only combined with prednisolone once a week for 4 weeks. Then, the therapeutic effects and adverse reactions were respectively observed in the 13 patients. RESULTS: Rituximab showed good and rapid efficacy in the treatment of refractory thrombocytopenia and autoimmune hemolytic anemia caused by systemic lupus erythematosus, Sjögren's syndrome, and mixed connective tissue disease. Only 1 patient had urinary tract infection. During 24-month follow-up, disease recurred in 7 patients who still responded to azathioprine/Tripterygium wilfordii. CONCLUSION: Low-dose rituximab has good efficacy and safety in the treatment of hematologic abnormalities in patients with connective tissue disease.


Assuntos
Doenças do Tecido Conjuntivo/tratamento farmacológico , Rituximab/uso terapêutico , Anemia Hemolítica Autoimune/tratamento farmacológico , Anemia Hemolítica Autoimune/etiologia , Anticorpos Monoclonais Murinos , Humanos , Lúpus Eritematoso Sistêmico/complicações , Síndrome de Sjogren/complicações , Trombocitopenia/tratamento farmacológico , Trombocitopenia/etiologia , Resultado do Tratamento
14.
Enzyme Microb Technol ; 129: 109357, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31307581

RESUMO

Corynebacterium glutamicum acetohydroxyacid synthase (AHAS), composed of two subunits IlvB and IlvN, catalyzes the first reaction in the biosynthetic pathway of branched-chain amino acids. It either condenses two pyruvates to yield acetolactate, leading to the biosynthesis of L-valine and L-leucine, or condenses pyruvate with 2-ketobutyrate to yield acetohydroxybutyrate, leading to L-isoleucine biosynthesis. However, the mechanism for the substrate specificity of C. glutamicum AHAS remains unknown. In this study, AHASs from an L-valine-producing C. glutamicum VWB-1 and an L-isoleucine-producing C. glutamicum IWJ001 were analyzed. The amino acid sequence of IlvN from both strains are the same, but the 138th and 404th residues of IlvB from the two strains are different; they are alanine and valine in IWJ001 (IlvB138A404V), but valine and alanine in VWB-1 (IlvB138V404A). When IlvB138A404V and IlvB138V404A were overexpressed in wild type C. glutamicum ATCC14067 and its △alr△aceE△ilvA△leuA mutant YTW-104, the latter led to much more L-valine production than the former. AHAS activity studies also showed that the 138th valine was important for binding the 2nd substrate pyruvate but not the 404th alanine. YTW-104/pJYW4-ilvB138V404A-ilvNCE could produce 25.93 g/L L-valine. The results indicate that the 138th valine of IlvB in AHAS could play an important role, leading to the increased L-valine biosynthesis in C. glutamicum.


Assuntos
Acetolactato Sintase/química , Proteínas de Bactérias/química , Corynebacterium glutamicum/enzimologia , Acetolactato Sintase/genética , Acetolactato Sintase/metabolismo , Motivos de Aminoácidos , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Butiratos/metabolismo , Corynebacterium glutamicum/química , Corynebacterium glutamicum/genética , Isoleucina/metabolismo , Ácido Pirúvico/metabolismo , Especificidade por Substrato , Valina/metabolismo
15.
Appl Microbiol Biotechnol ; 103(17): 7177-7189, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31317228

RESUMO

The selective marker in the plasmid-based expression system is usually a gene that encodes an antibiotic-resistant protein; therefore, the antibiotic has to add to maintain the plasmid when growing the bacteria. This antibiotic addition would lead to increase of production cost and the environment contamination. In this study, a novel Escherichia coli expression system, the lpxA deletion mutant harboring an lpxA-carrying vector, was developed. To develop this system, three plasmids pCas9Cre, pTF-A-UD, and pRSFCmlpxA were constructed. The plasmid pCas9Cre produces enzymes Cas9, λ-Red, and Cre and can be cured by growing at 42 °C; pTF-A-UD contains several DNA fragments required for deleting the chromosomal lpxA and can be cured by adding isopropyl-D-thiogalactopyranoside; pRSFCmlpxA contains the lpxA mutant lpxA123 and CamR. When E. coli were transformed with these three plasmids, the chromosomal lpxA and the CamR in pRSFCmlpxA can be efficiently removed, resulting in an E. coli lpxA mutant harboring pRSFlpxA. The lpxA is essential for the growth of E. coli; its relocation from chromosome to a constitutive expression vector is an ideal strategy to maintain the vector without antibiotic addition. The lpxA123 in pRSFlpxA can complement the deletion of the chromosomal lpxA and provide a strong selective pressure to maintain the plasmid pRSFlpxA. This study provides an experimental evidence that this novel expression system is convenient and efficient to use and can be used to improve L-threonine biosynthesis in the wild type E. coli MG1655 and an L-threonine producing E. coli TWF006.


Assuntos
Aciltransferases/genética , Cromossomos Bacterianos/genética , Escherichia coli/genética , Vetores Genéticos/genética , Deleção de Genes , Expressão Gênica , Genes Essenciais/genética , Teste de Complementação Genética , Plasmídeos/genética , Treonina/biossíntese
16.
J Ind Microbiol Biotechnol ; 46(11): 1557-1568, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31312942

RESUMO

L-Threonine is an important branched-chain amino acid and could be applied in feed, drugs, and food. In this study, L-threonine production in an L-threonine-producing Escherichia coli strain TWF001 was significantly increased by overexpressing the gene cluster phaCAB from Ralstonia eutropha. TWF001/pFW01-phaCAB could produce 96.4-g/L L-threonine in 3-L fermenter and 133.5-g/L L-threonine in 10-L fermenter, respectively. In addition, TWF001/pFW01-phaCAB produced 216% more acetyl-CoA, 43% more malate, and much less acetate than the vector control TWF001/pFW01, and meanwhile, TWF001/pFW01-phaCAB produced poly-3-hydroxybutyrate, while TWF001/pFW01 did not. Transcription analysis showed that the key genes in the L-threonine biosynthetic pathway were up-regulated, the genes relevant to the acetate formation were down-regulated, and the gene acs encoding the enzyme which converts acetate to acetyl-CoA was up-regulated. The results suggested that overexpression of the gene cluster phaCAB in E. coli benefits the enhancement of L-threonine production.


Assuntos
Proteínas de Bactérias/metabolismo , Cupriavidus necator/metabolismo , Escherichia coli/metabolismo , Família Multigênica , Treonina/biossíntese , Proteínas de Bactérias/genética , Cupriavidus necator/genética , Escherichia coli/genética , Hidroxibutiratos/metabolismo , Poliésteres/metabolismo
17.
J Thorac Dis ; 11(5): 1772-1778, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31285869

RESUMO

Background: Non-small cell lung cancer (NSCLC) is the most common cancer and the pathogenesis remain unclear. According to the competing endogenous RNA (ceRNA) theory, long noncoding RNA (lncRNA) have a competition with mRNAs for the connecting with miRNAs that affecting the level of mRNA. In this work, the ceRNA network and the important genes to predict the survival prognosis were explored. Methods: In the study, we recognized differently expressed genes (mRNAs, lncRNAs and miRNAs) between NSCLC and normal tissues from The Cancer Genome Atlas database (fold change >2, P<0.01) using edgeR. Then, the interaction between lncRNA and miRNA or mRNA and miRNA was explored by miRcode, miRDB, TargetScan, and miRanda. Furthermore, the functions and KEGG pathway were analyzed with DAVID and KOBAS. The connections of these mRNAs were explored by STRING online database. The relation between genes in the network and survival time were further explored by survival package in R. Results: By bioinformatics tools, we explored 155 lncRNAs, 30 miRNAs and 68 mRNAs and constructed ceRNA network. The functions and KEGG pathway of 68 mRNAs were further analyzed. AQP2, EGF, SLC12A1, TRPV5 and AVPR2 was in the center of network and may play key roles in the development of NSCLC. And mRNA (CCNB1, COL1A1, E2F7, EGLN3, FOXG1 and PFKP), miRNA (miR-31, miR-144 and miR-192) and lncRNA (AC080129.1, AC100791.1, AL163952.1, AP000525.1, AP003064.2, C2orf48, C10orf91, FGF12-AS2, HOTAIR, LINC00518, LNX1-AS1, MED4-AS1, MIG31HG, MUC2, TTTY16 and UCA1) were closely related with overall survival (OS). Conclusions: In summary, the present study provides a deeper understanding of the lncRNA-related ceRNA network in NSCLC and some genes may be new target to treat for NSCLC patients.

18.
Chem Commun (Camb) ; 55(65): 9681-9684, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31347618

RESUMO

Here, we report a convenient, fast labeling strategy for the imaging of cell surface sialic acids (SAs, nine-carbon monosaccharides located at the terminals of cell surface sugar chains). This strategy is based on the synthesis of sticky, furry and fluorescent "wool-balls", which are wound into nanoclusters from p-benzoquinone/ethylenediamine polymer "wires". With abundant amino groups at the surface, the wool-balls can easily stick to the C-7 aldehyde group generated at the ends of periodate treated SAs in less than 30 min.


Assuntos
Benzoquinonas/química , Etilenodiaminas/química , Corantes Fluorescentes/química , Nanopartículas/química , Polímeros/química , Ácidos Siálicos/análise , Animais , Benzoquinonas/síntese química , Linhagem Celular Tumoral , Etilenodiaminas/síntese química , Fluorescência , Humanos , Camundongos , Microscopia de Fluorescência/métodos , Neuraminidase/química , Tamanho da Partícula , Polímeros/síntese química , Células RAW 264.7 , Bases de Schiff/síntese química , Bases de Schiff/química , Ácidos Siálicos/química
19.
J Sci Food Agric ; 99(13): 5994-6000, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31215047

RESUMO

BACKGROUND: Dynamic high-pressure microfluidization (DHPM) is an emerging and promising technique for continuous production of fluid foods. This study aimed to investigate the influence of DHPM and conventional homogenization (CH) on the quality of peach juice. Processing was performed by passing peach juice through CH at 20 MPa and DHPM at 20-160 MPa for one or three passes. The effect of DHPM pressure and passing number were also assessed. RESULTS: The results indicate that DHPM could maintain the antioxidant activity of peach juice much better than CH processing. Total phenolic compounds were decreased by 11.7% and 7.9%-15.8% through CH and DHPM processing in different conditions. Moreover, particle size, non-enzymatic browning index and turbidity decreased significantly under DHPM and CH processing, and decreased more and more with the increasing of DHPM pressure and treatment times. However, vitamin C content and zeta-potential did not reveal remarkable variation before and after these two types of processing. CONCLUSION: Taken together, DHPM is able to maintain the quality and stability of peach juice, which can be a reliable technological alternative to CH to produce fresh-like peach juices. © 2019 Society of Chemical Industry.


Assuntos
Manipulação de Alimentos/métodos , Sucos de Frutas e Vegetais/análise , Preparações de Plantas/química , Prunus persica/química , Manipulação de Alimentos/instrumentação , Fenóis/química , Pressão
20.
Biomed Res Int ; 2019: 5012648, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31179325

RESUMO

Circulating microRNAs (miRNAs) are potential biomarkers for cardiovascular diseases. Our study aimed to determine whether miR-22-5p, miR-132-5p, and miR-150-3p represent novel biomarkers for acute myocardial infarction (AMI). Plasma samples were isolated from 35 AMI patients and 55 matched controls. Total RNA was extracted, and quantitative real-time PCR and ELISA were performed to investigate the expressions of miRNAs and cardiac troponin I (cTnI), respectively. We found that plasma levels of miR-22-5p and miR-150-3p were significantly higher during the early stage of AMI and their expression levels peaked earlier than cTnI. Conversely, circulating miR-132-5p was sustained at a low level during the early phase of AMI. All three circulating miRNAs were correlated with plasma cTnI levels. A receiver operating characteristic (ROC) analysis suggested that each single miRNA had considerable diagnostic efficacy for AMI. Moreover, combining the three miRNAs improved their diagnostic efficacy. Furthermore, neither heparin nor medications for coronary heart disease (CHD) affected plasma levels of miR-22-5p and miR-132-5p, but circulating miR-150-3p was downregulated by medications for CHD. We concluded that plasma miR-22-5p, miR-132-5p, and miR-150-3p may serve as candidate diagnostic biomarkers for early diagnosis of AMI. Moreover, a panel consisting of these three miRNAs may achieve a higher diagnostic value.


Assuntos
Biomarcadores/sangue , MicroRNAs/sangue , Infarto do Miocárdio/sangue , Infarto do Miocárdio/diagnóstico , Adulto , MicroRNA Circulante/sangue , Estudos de Coortes , Diagnóstico Precoce , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Intervenção Coronária Percutânea , Plasma , Curva ROC , Troponina I/sangue
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