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1.
Food Res Int ; 138(Pt A): 109665, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33292955

RESUMO

Russian sturgeon is a high-quality cultured fish and traditional heating methods may lead to deterioration of its food quality. This study aimed to evaluate the food quality and microbial composition of sturgeon fillets by low temperature vacuum heating (LTVH) and storage at 4 °C. The treatments varied in temperature (50, 60, and 70 °C) and duration (15 and 30 min); samples treated by traditional heating (100 °C, 15 min) methods were included as controls. We found that LTVH could reduce the values of lightness (L*), yellowness (b*), and pH and increase the values of redness (a*), chewiness, and hardness, to promote food quality. The biogenic amine content declined with the increase in heating temperature and time, the histamine of most concern was low at the end of storage, the values of LTVH70-30 and TC was 33.12 ± 1.25 and 30.39 ± 0.86 mg/kg. The total viable count (TVC) and biogenic amines showed the same trend, and the finial TVC values of LTVH60-30, LTVH70-15, LTVH70-30 and TC were 6.72 ± 0.17, 6.33 ± 0.18, 6.18 ± 0.08 and 5.93 ± 0.16 log CFU/g, which did not exceed the limit value (7 log CFU/g), indicating that the biosafety risk was reduced. According to the high-throughput sequencing results, the microbial composition of LTVH samples showed a lesser abundance pseudomonads than that found in the control. Thus, LTVH technology could be used as an alternative to traditional heating treatment.

2.
Med Hypotheses ; : 110366, 2020 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-33208242

RESUMO

Alcohol is a well-recognized hepatic carcinogen. Alcohol is metabolized into genotoxic acetaldehyde in hepatocytes, which is catalyzed by aldehyde dehydrogenase 2 (ALDH2). The detailed underlying mechanisms of alcohol-related hepatocellular carcinoma (HCC) remains unclear, at least partially, due to the absence of appropriate experimental models. Current studies suggest that rodents are not good models of the most common liver diseases that trigger HCC including alcoholic liver injury. We hypothesize that ethanol could induce transformation of immortalized normal liver cells, which may serve as a versatile tool for studying alcoholic HCC. Besides, we believe that knockout of ALDH2 will help to shorten the time course of transformation, as ALDH2 deficiency will significantly increase the accumulation of acetaldehyde in hepatocytes. Using this model, the dynamic changes of carcinogenesis-related molecular events could be easily examined. Furthermore, the transformed cells isolated from soft agar could be inoculated to mice for studying invasion, metastasis, and also for screening prophylactics.

3.
Huan Jing Ke Xue ; 41(7): 3112-3120, 2020 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-32608883

RESUMO

In this study, 127 light-duty gasoline cars and 10 light-duty gasoline trucks with different emission standards were selected to explore the influences of different conditions and vehicle parameters on the emission characteristics of carbon dioxide (CO2), carbon monoxide (CO), nitrogen oxides (NOx), hydrocarbons (HC), and methane (CH4) using a portable emission measurement system based on a chassis dynamometer under acceleration simulation mode. The results showed that the gaseous pollutants of light-duty gasoline vehicles displayed a relatively lower emission rate under the idle condition, which accounted for only 22.9% and 25.8% of the emission rate at the accelerated condition and constant speed condition, respectively. The pollutant emission characteristics were closely related to the working conditions. The emission rates of CO2 and NOx in the accelerated condition were less than those at the constant speed condition, while the emission rates of CO, HC, and CH4 in the accelerated condition were higher than those at the constant speed condition. In the constant low-speed condition, the emission factors of CO2, CO, NOx, HC, and CH4 were 383.20, 2.98, 1.60, 0.14, and 0.03 g·km-1 for light-duty gasoline cars, respectively, and 360.66, 2.64, 1.61, 0.0055, and 0.0027 g·km-1 for light-duty gasoline trucks, respectively. Tighter emission standards have caused significant reductions in emissions. The emission factors of CO, NOx, HC, and CH4 could be decreased by 87.5%, 97.3%, 97.9%, and 86.4%, respectively, from China Ⅰ to China Ⅴ. A non-linear relationship was found between the age, odometer, vehicle weight, and vehicular emissions. In addition, the engine displacement was positively correlated with vehicular emissions.

4.
Chem Biol Interact ; 327: 109176, 2020 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-32534989

RESUMO

Alcoholic liver disease (ALD) is a progressively aggravated liver disease with high incidence in alcoholics. Ethanol-induced fat accumulation and the subsequent lipopolysaccharide (LPS)-driven inflammation bring liver from reversible steatosis, to irreversible hepatitis, fibrosis, cirrhosis, and even hepatocellular carcinoma. Peroxisome proliferator-activated receptor α (PPARα) is a member of the nuclear receptor superfamily of ligand-activated transcription factors and plays pivotal roles in the regulation of fatty acid homeostasis as well as the inflammation control in the liver. It has been well documented that PPARα activity and/or expression are downregulated in liver of mice exposed to ethanol, which is thought to be one of the prime contributors to ethanol-induced steatosis, hepatitis and fibrosis. This article summarizes the current evidences from in vitro and animal models for the critical roles of PPARα in the onset and progression of ALD. Importantly, it should be noted that the expression of PPARα in human liver is reported to be similar to that in mice, and PPARα expression is downregulated in the liver of patients with nonalcoholic fatty liver disease (NAFLD), a disease sharing many similarities with ALD. Therefore, clinical trials investigating the expression of PPARα in the liver of ALD patients and the efficacy of strong PPARα agonists for the prevention and treatment of ALD are warranted.


Assuntos
Fígado Gorduroso Alcoólico/etiologia , PPAR alfa/metabolismo , Adiponectina/metabolismo , Animais , Peptídeos e Proteínas de Sinalização do Ritmo Circadiano/metabolismo , Regulação para Baixo , Etanol , Fígado Gorduroso Alcoólico/metabolismo , Humanos , Inflamação/induzido quimicamente , Inflamação/etiologia , Inflamação/metabolismo , Fígado/metabolismo , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/etiologia , Cirrose Hepática/metabolismo , Neoplasias Hepáticas/induzido quimicamente , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/metabolismo , PPAR alfa/agonistas , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo
5.
Int J Syst Evol Microbiol ; 70(6): 3740-3748, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32441611

RESUMO

A Gram-stain-negative, aerobic, gliding, rod-shaped (0.2-0.5×1.0-13.0 µm) and yellow-pigmented bacterium, designated PLHSN227T, was isolated from seawater collected near the coast of Yantai, PR China. PLHSN227T was found to grow at 15-37 °C (optimum, 28-30 °C) and pH 6.0-8.5 (optimum, 6.5-7.5) in the presence of 2-14 % (w/v) NaCl (optimum, 5.0 %). Phylogenetic analysis of the 16S rRNA gene sequences revealed that PLHSN227T represented a member of the family Flavobacteriaceae and exhibited the highest sequence similarity (94.6 %) to the type strain Salegentibacter holothuriorum NBRC 100249T. The chemotaxonomic analysis revealed that the sole respiratory quinone was menaquinone 6 (MK-6) and the major fatty acids included C19 : 0ω8c cyclo, iso-C15 : 0, anteiso-C15 : 0, C18 : 0 and summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c). The major polar lipids included phosphatidylethanolamine, one unidentified aminolipid and two unidentified lipids. The DNA G+C content of PLHSN227T was 35.6 mol%. PLHSN227T showed the highest average amino acid identity value of 67.2 %, the average nucleotide identity value of 75.6 and 14.5 % digital DNA-DNA hybridization identity with Mesonia algae DSM 15361T. According to the phylogenetic data, PLHSN227T formed a distinct clade in the phylogenetic tree. On the basis of phenotypic, chemotaxonomic and phylogenetic data, it is considered that PLHSN227T represents a novel genus within the family Flavobacteriaceae, for which the name Haloflavibacter putidus gen. nov., sp. nov. is proposed. The type strain is PLHSN227T (=KCTC 72159T=MCCC 1H00371T).


Assuntos
Flavobacteriaceae/classificação , Filogenia , Água do Mar/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Flavobacteriaceae/isolamento & purificação , Hibridização de Ácido Nucleico , Fosfatidiletanolaminas/química , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
6.
Comput Biol Chem ; 85: 107229, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32058945

RESUMO

BACKGROUND: Biomarkers are important in the study of tumor processes for early detection and precise treatment. The biomarkers that have been previously detected are not useful for clinical application for primary colorectal carcinoma (PCRC). The aim of this study was to explore clinically valuable biomarkers of PCRC based on integrated bioinformatic analysis. MATERIAL AND METHODS: Gene expression data were acquired from the GSE41258 dataset, and the differentially expressed genes were determined between PCRC and normal colorectal samples. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses were implemented via Gene Set Enrichment Analysis. A protein-protein interaction (PPI) network was constructed. The significant modules and hub genes were screened and identified in the PPI network. RESULTS: A total of 202 DEGs were identified, including 58 upregulated and 144 downregulated genes in PCRC samples compared to those in normal colorectal samples. Enrichment analysis demonstrated that the gene sets enriched in PCRC were significantly related to bicarbonate transport, regulation of sodium ion transport, potassium ion homeostasis, regulation of telomere maintenance, and other processes. A total of 10 hub genes was identified by cytoHubba: PYY, CXCL3, CXCL11, CXCL8, CXCL12, CCL20, MMP3, P2RY14, NPY1R, and CXCL1. CONCLUSION: The hub genes, such as NPY1R, P2RY14, and CXCL12, and the electrolyte disequilibrium resulting from the differential expression of genes, especially bicarbonate imbalance, may provide novel insights and evidence for the future diagnosis and targeted therapy of PCRC.

7.
Nat Prod Res ; : 1-7, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31707857

RESUMO

A new indole alkaloid, namely naucleofficine H (1), was obtained from the aqueous extract of Nauclea officinalis, together with four known alkaloids, vincosamide (2), strictosamide (3), angustoline (4) and pumiloside (5). Their structures were characterized by analyzing their physicochemical data including NMR, and HRMS. In addition, five compounds were tested for their proliferation activities. The expression of vascular endothelial growth factor (VEGF), extra-cellular signal-regulated protein kinase 1 and 2 (ERK) and phosphorylation of ERK 1/2 (p-ERK) were also detected in HUVEC treated withbioactive compounds using western blotting. The result showed that these compounds could promote HUVEC cell proliferation. Compounds 3 and 5 could up-regulate VEGF and p-ERK in HUVEC.

8.
J Biol Chem ; 294(38): 13915-13927, 2019 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-31350334

RESUMO

Replication protein A (RPA) is the major eukaryotic ssDNA-binding protein and has essential roles in genome maintenance. RPA binds to ssDNA through multiple modes, and recent studies have suggested that the RPA-ssDNA interaction is dynamic. However, how RPA alternates between different binding modes and modifies ssDNA structures in this dynamic interaction remains unknown. Here, we used single-molecule FRET to systematically investigate the interaction between human RPA and ssDNA. We show that RPA can adopt different types of binding complexes with ssDNAs of different lengths, leading to the straightening or bending of the ssDNAs, depending on both the length and structure of the ssDNA substrate and the RPA concentration. Importantly, we noted that some of the complexes are highly dynamic, whereas others appear relatively static. On the basis of the above observations, we propose a model explaining how RPA dynamically engages with ssDNA. Of note, fluorescence anisotropy indicated that RPA can also associate with RNA but with a lower binding affinity than with ssDNA. At the single-molecule level, we observed that RPA is undergoing rapid and repetitive associations with and dissociation from the RNA. This study may provide new insights into the rich dynamics of RPA binding to ssDNA and RNA.


Assuntos
DNA de Cadeia Simples/metabolismo , RNA/química , Proteína de Replicação A/metabolismo , Cromatografia em Gel , DNA de Cadeia Simples/química , Polarização de Fluorescência/métodos , Transferência Ressonante de Energia de Fluorescência , Humanos , Ligação Proteica , RNA/metabolismo , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Proteína de Replicação A/química , Proteína de Replicação A/genética
9.
Environ Sci Technol ; 53(12): 6927-6936, 2019 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-31117534

RESUMO

Promotion of iron solubility using ligands is the preliminary step in the homogeneous electro-Fenton (EF) process at a mild pH, but the chelate efficiencies of most organic ligands are unsatisfactory, resulting in insufficient Fe(II) availability. In this study, atomic H* was, for the first time, introduced to the EF process to accelerate the regeneration of the Fe(II)-complex at a mild pH using a Ni-deposited carbon felt (Ni-CF) cathode. The introduction of atomic H* significantly elevated total organic carbon (TOC) abatement of ciprofloxacin (CIP) from 42% (CF) to 81% (Ni-CF) at a natural pH. In the presence of humic acids (HAs), atomic H* introduced via Ni-CF enhanced the CIP degradation rate to 10 times that of the CF at a mild pH. The electron spin resonance (ESR), density functional theory (DFT) calculations, electrochemical characterization, and in situ electrochemical Raman study clearly demonstrated that the atomic H* generated from the Ni-CF cathode was highly efficient at reducing Fe(III)-complexes at a natural pH. Additionally, the Ni-CF could generate atomic H* without significant nickel leaching. Thus, the atomic H* could continuously facilitate iron cycling and, consequently, enhance pollutant mineralization via the homogeneous EF process at a mild pH in an environmentally friendly manner.


Assuntos
Compostos Ferrosos , Poluentes Químicos da Água , Eletrodos , Compostos Férricos , Peróxido de Hidrogênio , Concentração de Íons de Hidrogênio , Oxirredução
10.
Environ Sci Technol ; 53(8): 4397-4405, 2019 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-30908036

RESUMO

Pyrogenic carbonaceous matter (PCM) catalyzes the transformation of a range of organic pollutants by sulfide in water; however, the mediation mechanisms are not fully understood. In this study, we observed for the first time that the degradation of azo dyes by sulfide initially underwent a lag phase followed by a fast degradation phase. Interestingly, the presence of PCM only reduced the lag phase length of the azo dye decolorization but did not significantly enhance the reaction rate in the fast degradation phase. An analysis of the azo dye reduction and polysulfide formation indicated that PCM facilitated the transformation of sulfide into polysulfides, including disulfide and trisulfide, resulting in fast azo dye reduction. Moreover, the oxygen functional groups of the PCM, especially the quinones, may play an important role in the transformation of sulfide into polysulfides by accelerating the electron transfer. The results of this study provide a better understanding of the PCM-mediated abiotic transformation of organic pollutants by sulfide in anaerobic aqueous environments.


Assuntos
Compostos Azo , Sulfetos , Corantes , Transporte de Elétrons , Oxirredução , Quinonas
11.
J Cell Biochem ; 120(4): 5151-5159, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30324678

RESUMO

More and more evidence indicate long noncoding RNAs (lncRNAs) as competing endogenous RNAs (ceRNAs) to indirectly regulate messenger RNAs (mRNAs) by acting as microRNA (miRNA) sponges, which represents a novel layer of gene regulation that plays a critical role in the development of cancers. However, functional roles and regulatory mechanisms of lncRNA-mediated ceRNAs network in osteosarcoma are still largely unknown. Here, we comprehensively compared the expression profiles of mRNAs, lncRNAs, and miRNAs between osteosarcoma and normal samples from the Gene Expression Omnibus (GEO) to elaborate related latent mechanisms. Two lncRNAs, ie, LINC01560 and MEG3, were identified to be aberrantly expressed. Importantly, MEG3 was considered as a promising diagnostic biomarker and therapeutic target for patients with osteosarcoma according to the Kaplan-Meier analysis of another independent osteosarcoma data set from the Cancer Genome Atlas (P = 0.05). Eventually, we successfully established a dysregulated lncRNA-related ceRNA network, including one osteosarcoma-specific lncRNA, three miRNAs and four mRNAs. In conclusion, this study should be beneficial for improving our understanding of the lncRNA-mediated ceRNA regulatory mechanisms in the pathogenesis of osteosarcoma and providing it with novel candidate diagnostic and therapeutic biomarkers.


Assuntos
Carcinogênese/patologia , MicroRNAs/metabolismo , Osteossarcoma/genética , Osteossarcoma/patologia , RNA Longo não Codificante/metabolismo , Carcinogênese/genética , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Humanos , MicroRNAs/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
12.
J Agric Food Chem ; 66(46): 12217-12226, 2018 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-30375865

RESUMO

The metabolism of widely used aryloxyphenoxypropionate herbicides has been extensively studied in microbes. However, the information on the degradation of diclofop-methyl (DCM) is limited, with no genetic and biochemical investigation reported. The consortium L1 of Rhodococcus sp. JT-3 and Brevundimonas sp. JT-9 was able to degrade DCM through a synergistic metabolism. To elaborate the molecular mechanism of DCM degradation, the metabolic pathway for DCM was first investigated. DCM was initially transformed by strain JT-3 to diclofop acid and then by strain JT-9 to 2-(4-hydroxyphenoxy) propionic acid as well as 2,4-dichlorophenol. Subsequently, the two dcm gene clusters, dcmAE and dcmB1B2CD, involved in further degradation of 2,4-dichlorophenol, were successfully cloned from strain JT-3, and the functions of each gene product were identified. DcmA, a glutathione-dependent dehalogenase, was responsible for catalyzing the reductive dehalogenation of 2,4-dichlorophenol to 4-chlorophenol, which was then converted by the two-component monooxygenase DcmB1B2 to 4-chlorocatechol as the ring cleavage substrate of the dioxygenase DcmC. In this study, the overall DCM degradation pathway of the consortium L1 was proposed and, particularly, the lower part on the DCP degradation was characterized at the genetic and biochemical levels.


Assuntos
Proteínas de Bactérias/metabolismo , Caulobacteraceae/metabolismo , Éteres Difenil Halogenados/metabolismo , Herbicidas/metabolismo , Consórcios Microbianos , Família Multigênica , Rhodococcus/metabolismo , Proteínas de Bactérias/genética , Biodegradação Ambiental , Caulobacteraceae/enzimologia , Caulobacteraceae/genética , Dioxigenases/genética , Dioxigenases/metabolismo , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/metabolismo , Rhodococcus/enzimologia , Rhodococcus/genética
13.
J Biol Chem ; 293(48): 18504-18513, 2018 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-30305390

RESUMO

G-quadruplexes (G4s) are four-stranded DNA structures formed by Hoogsteen base pairing between stacked sets of four guanines. Pif1 helicase plays critical roles in suppressing genomic instability in the yeast Saccharomyces cerevisiae by resolving G4s. However, the structural properties of G4s in S. cerevisiae and the substrate preference of Pif1 for different G4s remain unknown. Here, using CD spectroscopy and 83 G4 motifs from S. cerevisiae ranging in length from 30 to 60 nucleotides, we first show that G4 structures can be formed with a broad range of loop sizes in vitro and that a parallel conformation is favored. Using single-molecule FRET analysis, we then systematically addressed Pif1-mediated unwinding of various G4s and found that Pif1 is sensitive to G4 stability. Moreover, Pif1 preferentially unfolded antiparallel G4s rather than parallel G4s having similar stability. Furthermore, our results indicate that most G4 structures in S. cerevisiae sequences have long loops and can be efficiently unfolded by Pif1 because of their low stability. However, we also found that G4 structures with short loops can be barely unfolded. This study highlights the formidable capability of Pif1 to resolve the majority of G4s in S. cerevisiae sequences, narrows the fractions of G4s that may be challenging for genomic stability, and provides a framework for understanding the influence of different G4s on genomic stability via their processing by Pif1.


Assuntos
DNA Helicases/metabolismo , DNA Fúngico/química , DNA Fúngico/metabolismo , Quadruplex G , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Dicroísmo Circular , Transferência Ressonante de Energia de Fluorescência , Instabilidade Genômica , Ligação Proteica , Saccharomyces cerevisiae/genética , Temperatura
14.
Huan Jing Ke Xue ; 39(8): 3826-3834, 2018 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-29998692

RESUMO

To explore the sources of peak nitrous oxide (N2O) flushes in solar greenhouse vegetable field, an experiment was conducted with two conventional vegetable soils under different initial volume fractions of oxygen (O2) (0%, 1%, 3%, 5%, and 10%). A robotized incubation system was employed to analyze the gas kinetics[O2, N2O, nitric oxide (NO), nitrogen (N2), and carbon dioxide (CO2)] every 6 or 8 h and calculate the N2O/(NO+N2O+N2) index. Sodium chlorate (NaClO3) was used to inhibit the oxidation of NO2- to further explore the relationship between N2O and nitrite (NO2-). A parallel off-line incubation in triplicates was conducted under similar conditions to measure the dynamic changes in inorganic nitrogen content[ammonia (NH4+), nitrate (NO3-), and NO2-]. The results showed that N2O production under anaerobic condition was significantly higher than that under aerobic condition. The peak value of N2O in the soil collected from a straw-added plot (DIS) was significantly higher than that in the soil from non-straw added plot (DI) (P<0.01) when the volume fraction of oxygen was ≤ 1%. Oxygen can directly affect N2O production by delaying or inhibiting N2O reduction, with significant increase in N2O production rate under oxygen-depleted condition. However, the N2production rate decreased significantly with increase in initial oxygen volume fraction (P<0.01). When the initial volume fraction of oxygen was between 1% and 5%, a continuous accumulation of NO2- was observed during the incubation period, resulting in the significantly higher N2O/(NO+N2O+N2) index than that in either anaerobic or 10% of oxygen treatments. Furthermore, a linear correlation was observed between NO2- and N2O at 5% and 10% of oxygen with the addition of NaClO3 (R2 ≥ 0.85). Incomplete denitrification and nitrifier denitrification from NO2- induction co-occurred in the range of 1% and 5% volume fractions of oxygen, significantly increasing the soil N2O production and N2O/(NO+N2O+N2) index. In addition, N2O production under anaerobic condition was significantly higher than that under aerobic condition (P<0.01).


Assuntos
Óxido Nitroso/análise , Oxigênio/química , Solo/química , Desnitrificação , Verduras
15.
J Chromatogr B Analyt Technol Biomed Life Sci ; 1087-1088: 80-89, 2018 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-29723699

RESUMO

The compounds of N-Methylanhydrotetrahydroberberrubine A, dictamnine and eudesmin were the primary bioactive components in the roots of Zanthoxylum armatum DC (Z. armatum). To clarify the pharmacokinetics and distribution of these three compounds, an ultra-fast liquid chromatography-tandem mass spectrometry (UFLC-MS/MS) was employed to determine the contents of these three compounds in rat plasma and seven tissues. The separation was achieved on a Kinetex XB-C18 100A column (2.1 × 50 mm, 2.6 µm, Phenomenex). The optimized mobile phase system was set with 0.1‰ formic acid aqueous solution (A) and acetonitrile (containing 0.1‰ formic acid) (B) with a programmed elution of 0.00 to 0.50 min, 2% B; 0.51-4.00 min, 30%-60% B; and 4.01-5.00 min, 2% B. All analytes were measured with optimized multiple reaction monitoring (MRM) in the positive ion ESI mode. Berberine hydrochloride was selected as the internal standard (IS). The MS/MS transitions of N-Methylanhydrotetrahydroberberrubine A, dictamnine, eudesmin and IS were 339.9135.1, 200.1 → 129.1, 387.4 → 369.0 and 337.1 → 321.1, respectively. The lower limits quantification (LLOQ) of the three analytes was 0.5-20 ng/ml. The linear ranges were 0.5-400 ng/ml for N-Methylanhydrotetrahydroberberrubine A and dictamnine and 20-4000 ng/ml for eudesmin. The present analysis showed that the two alkaloids were quickly absorbed, with Tmax in 0.167-0.292 h, and eudesmin was absorbed in 2.5 h. Moreover, all compounds were found at high concentrations in the gastrointestinal track. These results are helpful for further investigation of the clinical application of Z. armatum.


Assuntos
Berberina , Furanos , Lignanas , Quinolinas , Zanthoxylum/química , Animais , Berberina/análogos & derivados , Berberina/análise , Berberina/química , Berberina/farmacocinética , Cromatografia Líquida de Alta Pressão , Feminino , Furanos/análise , Furanos/química , Furanos/farmacocinética , Lignanas/análise , Lignanas/química , Lignanas/farmacocinética , Limite de Detecção , Modelos Lineares , Masculino , Extratos Vegetais/administração & dosagem , Extratos Vegetais/farmacocinética , Quinolinas/análise , Quinolinas/química , Quinolinas/farmacocinética , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem , Distribuição Tecidual
16.
Biochem Biophys Res Commun ; 499(1): 8-16, 2018 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-29534962

RESUMO

Gastric cancer is the third leading cause of cancer-associated death worldwide. Although a decrease in its incidence is observed, gastric cancer still poses a major clinical challenge due to poor prognosis and limited treatments. Barbaloin (BBL) is a main medicinal composition of the Chinese traditional medicine aloe vera. BBL has various bioactivities, including anti-oxidant, anti-inflammatory and anti-tumor properties. Polydopamine (pD)-based surface modification is easy to functionalize polymeric nanoparticles (NPs) surfaces with ligands and/or additional polymeric layers. In the present study, BBL-loaded formulations was developed with pD-modified NPs, which was synthesized by polylactide-TPGS (PLA-TPGS) (pD-PLA-TPGS/NPs). And galactosamine (Gal) was conjugated on the prepared NPs (Gal-pD-PLA-TPGS/NPs) for targeting the gastric cancer cells. Here, we found that BBL-loaded Gal-pD-PLA-TPGS/NPs showed the highest cellular uptake efficacy in gastric cancer cells. Gal-pD-PLA-TPGS/NPs more significantly reduced the gastric cancer cell viability. Further, greater apoptosis, autophagy and ROS generation was induced by Gal-pD-PLA-TPGS/NPs in gastric cancer cells. Additionally, compared to the other two NPs, Gal-pD-PLA-TPGS/NPs most markedly decreased ATP levels in gastric cancer cells. In vivo, Gal-pD-PLA-TPGS/NPs were specifically targeted to tumor site. Moreover, Gal-pD-PLA-TPGS/NPs exhibited the most anti-tumor effects, as evidenced by the lowest tumor volume and tumor weight. Of note, there was no significant difference was observed in body and liver weight, as well as the histological changes in major organs isolated from each group of mice. Together, the findings indicated that BBL-loaded Gal-pD-PLA-TPGS/NPs could be targeted to gastric cancer cells to suppress tumor progression without toxicity.


Assuntos
Antracenos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Sistemas de Liberação de Medicamentos , Células Epiteliais/efeitos dos fármacos , Nanopartículas/química , Neoplasias Gástricas/tratamento farmacológico , Animais , Antracenos/química , Antineoplásicos Fitogênicos/química , Transporte Biológico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Composição de Medicamentos/métodos , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Galactosamina/química , Galactosamina/metabolismo , Humanos , Indóis/química , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanopartículas/administração & dosagem , Poliésteres/química , Polímeros/química , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Resultado do Tratamento , Carga Tumoral/efeitos dos fármacos , Vitamina E/química , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Bioelectrochemistry ; 119: 180-188, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29054074

RESUMO

This study evaluated the effect of temperature on methane production by CO2 reduction during microbial electrosynthesis (MES) with a mixed-culture biocathode. Reactor performance, in terms of the amount and rate of methane production, current density, and coulombic efficiency, was compared at different temperatures. The microbial properties of the biocathode at each temperature were also analyzed by 16S rRNA gene sequencing. The results showed that the optimum temperature for methane production from CO2 reduction in MES with a mixed-culture cathode was 50°C, with the highest amount and rate of methane production of 2.06±0.13mmol and 0.094±0.01mmolh-1, respectively. In the mixed-culture biocathode MES, the coulombic efficiency of methane formation was within a range of 19.15±2.31% to 73.94±2.18% due to by-product formation at the cathode, including volatile fatty acids and hydrogen. Microbial analysis demonstrated that temperature had an impact on the diversity of microbial communities in the biofilm that formed on the MES cathode. Specifically, the hydrogenotrophic methanogen Methanobacterium became the predominant archaea for methane production from CO2 reduction, while the abundance of the aceticlastic methanogen Methanosaeta decreased with increased temperature.


Assuntos
Dióxido de Carbono/metabolismo , Eletroquímica/instrumentação , Metano/metabolismo , Temperatura , Fontes de Energia Bioelétrica/microbiologia , Dióxido de Carbono/química , Eletrodos , RNA Ribossômico 16S/genética , Análise de Sequência de RNA
18.
Nanoscale ; 9(48): 19100-19107, 2017 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-29143038

RESUMO

Saturable absorbers (SAs) have interesting applications for the realization of pulsed lasers in various wavelengths of fiber and solid-state lasers. Topological insulators (TIs) have been recently discovered to feature saturable absorption due to their unique band structure. In this study, high-purity layers of Bi2Te3 thin film SA have been successfully prepared using the spin coating-coreduction approach (SCCA). Compared with the typical method of preparing SAs, the SCCA can be used to prepare topological insulator saturable absorbers (TISAs) with high optical quality, large area consistency, and controllable thickness, which is critical for pulsed lasers. To the best of our knowledge, this study is the first observation and discussion of clear thickness-dependent optical nonlinearity. In this study, a Q-switched bulk Nd:YAG laser is demonstrated and investigated using the prepared TISA as the absorber. The timing jitter and amplitude fluctuation of the stable pulse laser indicated that the SCCA is suitable for fabricating a Bi2Te3 SA. Furthermore, the SCCA enables the establishment of a pulsing laser through saturation intensity engineering.

19.
Appl Opt ; 55(20): 5341-4, 2016 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-27409308

RESUMO

A laser diode array (LDA) end-pumped continuous-wave single-frequency Innoslab amplifier has been demonstrated. The Gaussian ray bundle method was used to model the light propagation in the Innoslab amplifier for the first time to the best of our knowledge. With discrete reflectors, the maximum output of 60 W with a linewidth of 44 MHz was achieved under the pump power of 245 W, corresponding to the optical-optical efficiency of 24.5%. The beam quality factor M2 at the output power of 51 W in the horizontal and vertical direction was measured to be 1.4 and 1.3, respectively. The long-term power instability in 2 h was less than 0.25%.

20.
Appl Opt ; 54(23): 7120-3, 2015 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-26368385

RESUMO

In this study, we experimentally demonstrate the generation of 760 fs pulse duration from a diode-pumped Yb:LuAG mode-locked laser at 1032 nm. At the repetition rate of 58.6 MHz, the maximum average power of 1.07 W was obtained, corresponding to the peak power of 24 kW. To our knowledge, these results represent the shortest pulse duration and highest peak power ever obtained for a 1032 nm mode-locked laser with Yb:LuAG crystal.

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