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1.
Int J Biol Macromol ; 275(Pt 1): 133522, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38945325

RESUMO

A facile biphasic system composed of choline chloride (ChCl)-based deep eutectic solvent (DES) and methyl isobutyl ketone (MIBK) was developed to realize the furfural production, lignin separation and preparation of fermentable glucose from Eucalyptus in one-pot. Results showed that the ChCl/1,2-propanediol/MIBK system owned the best property to convert hemicelluloses into furfural. Under the optimal conditions (MRChCl:1,2-propanediol = 1:2, raw materials:DES:MIBK ratio = 1:4:8 g/g/mL, 0.075 mol/L AlCl3·6H2O, 140 °C, and 90 min), the furfural yield and glucose yield reached 65.0 and 92.2 %, respectively. Meanwhile, the lignin with low molecular weight (1250-1930 g/mol), low polydispersity (DM = 1.25-1.53) and high purity (only 0.08-2.59 % carbohydrate content) was regenerated from the biphasic system. With the increase of pretreatment temperature, the ß-O-4, ß-ß and ß-5 linkages in the regenerated lignin were gradually broken, and the content of phenolic hydroxyl groups increased, but the content of aliphatic hydroxyl groups decreased. This research provides a new strategy for the comprehensive utilization of lignocellulose in biorefinery process.

2.
Bioresour Technol ; 369: 128392, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36435421

RESUMO

The developing of pretreatment method to break the biomass barrier of lignocellulosic is a challenging task for achieve high value utilization. A fast microwave-assisted choline chloride/1,2-propanediol/methyl isobutyl ketone biphasic system was constructed for pretreating Eucalyptus to the production of furfural and cellulose-rich residues and the extraction of lignin. Results showed that the combination of AlCl3·6H2O and HCl had the best catalytic ability for furfural production among the examined catalysts. Under the optimal conditions (140 °C, 15 min, 0.075 M AlCl3·6H2O, 0.05 M HCl), the furfural yield of 55.4 %, the glucose yield of 90.3 % and the delignification rate of 92.4 % could be achieved. Moreover, the extracted lignin samples with a low polydispersity (1.55-1.73) and molecular weight (1380-2040 g/mol) are promising to act as precursor for the value-add products processing. These findings demonstrated an ultrafast pretreatment process with excellent results in biomass fractionation and comprehensive utilization of biomass components.


Assuntos
Eucalyptus , Lignina , Lignina/química , Propilenoglicol , Furaldeído , Biomassa , Colina/química , Micro-Ondas , Solventes/química , Hidrólise
3.
Carbohydr Polym ; 288: 119420, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35450662

RESUMO

The alkali-soluble hemicelluloses extracted with 10% KOH solution from corn bran were further isolated with different concentrations of aqueous ethanol solutions. Herein 92.2% of the original hemicelluloses can be obtained and the cellulase enzymatic hydrolysis rate of the alkali treated corn bran can reach to 97.2%. The corn bran hemicelluloses were mainly glucuronoarabinoxylan, in which xylose (48.4-53.8%) and arabinose (27.8-33.2%) were the main components. More linear hemicelluloses with high molecular weight tended to be precipitated in low concentration aqueous ethanol solutions. Furthermore, the relationship between the structural features of these alkali-soluble corn bran hemicelluloses and their furfural yield was investigated in MIBK (methyl isobutyl ketone)/H2O biphasic system. Results showed that the hemicelluloses with high xylose content are benefit to the furfural production, and the highest furfural yield of 67.7% was obtained.


Assuntos
Furaldeído , Xilose , Álcalis/química , Etanol/química , Furaldeído/química , Hidrólise , Água/química , Zea mays/química
4.
Bioresour Technol ; 352: 127074, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35346816

RESUMO

Developing a biorefinery process for a highly integrated valorization and fractionation of lignocellulose is crucial for its utilization. Herein, a biphasic system comprising choline chloride/lactic acid and 2-methyltetrahydrofuran with Al2(SO4)3 and H2SO4 as catalysts was applied to pretreat Eucalyptus. Results showed that under the optimized conditions (150 °C, 30 min, 0.2 M Al2(SO4)3, 0.075 M H2SO4), the furfural yield and enzymatic hydrolysis efficiency could reach 54.7% and 97.0%, respectively. The efficient cellulose conversion was attributed to remarkable removal of lignin (91.0%) and hemicelluloses (100.0%), thereby causing the disruption of cell wall structure and enhancement of cellulose accessibility. Meanwhile, confocal Raman microscope and atomic force microscope displayed that the pretreatment resulted in the decreasing intensities of carbohydrates and lignin different regions of cell walls, and exposing of the embedded microfibers from noncellulosic polymers. Overall, the deep eutectic solvent-based biphasic system displayed high performance for effective utilization of carbohydrate components in lignocellulose.


Assuntos
Furaldeído , Lignina , Biomassa , Carboidratos , Celulose , Solventes Eutéticos Profundos , Hidrólise , Lignina/química , Solventes
5.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1015683

RESUMO

Gut microbiome sequencing studies have great potential to translate microbial analysis outcomes into human health research. Sequencing strategies of 16S amplicon and whole-metagenome shotgun (WMS) are two main methods in microbiome research with respective advantages. However, how sample heterogeneity, sequencers and library preparation protocols affect the sequencing reproducibility of gut microbiome needs further investigation. This study aims to provide a reference for the selection of sequencing technologies by comparing differences in microbial composition from different sampling sites. The results of three widely adopted sequencers showed that the technical repetition correlation (r= 0. 94) was high in WMS method, while the biological repetition correlation (r = 0. 69) was low. Bray-Curtis distance identified that dissimilarity from biological replicates was larger than that of technical replicates (P<0. 001). In addition, dissimilarity and specific taxonomic profiles were observed between 16S and WMS datasets. Our results imply that homogenization is a necessary step before sample DNA extraction. The sequencers contributed less to taxonomic variation than the library preparation protocols. We developed an empirical Bayes approach that " borrowed information" in calculations and analyzed batch effect parameters using standardized data and prior distributions of (non-) parameters, which may improve population comparability between 16S and WMS and provide a basis for further application to fusion analysis of published 16S and microbial datasets.

6.
Acta Pharmaceutica Sinica ; (12): 2230-2240, 2021.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-887039

RESUMO

Excessive exercise makes the body consume more oxygen and produce excessive free radicals. The increased free radicals lead to oxidative stress injury and dysfunctions in liver tissue. Our previous study showed that Anwulignan, an active monomer in Schisandra sphenanthera Rehd. et Wils. (Schisandra), had anti-fatigue effects in mice. However, whether Anwulignan has a protective effect on liver damage in exhausted mice and the mechanism underlying remain elusive. An exhaustive swimming mice model was used to study the protective effects of Anwulignan on liver damage. The involvement of the nuclear factor (erythroid-derived 2)-like 2 (NRF2)/antioxidant responsive element (ARE) antioxidative pathway in Anwulignan-mediated anti-fatigue was analyzed using NRF2 inhibitor ML385 in HepG2 cells treated with H2O2. Animal welfare and experimental process follow the regulations of the Animal Ethics Committee of Beihua University. Anwulignan significantly lowered serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels, reduced liver tissue damages, increased superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT), and decreased malondialdehyde (MDA) and 8-hydroxy-2 deoxyguanosine (8-OHdG) contents in the livers of exhausted mice, demonstrating a strong antioxidant effect. Furthermore, Anwulignan up-regulated the NRF2/ARE antioxidant pathway in liver tissue, increased B-cell lymphoma 2 (Bcl-2) expression, and decreased Bcl-2-like protein 4 (Bax) and caspase3 expression. In HepG2 cells, Anwulignan improved the cell viability and SOD activity, reduced reactive oxygen species (ROS) and MDA contents, up-regulated the expression of the NRF2/ARE signaling pathway and Bcl-2, and decreased Bax and caspase3 expression in the cells. Furthermore, pretreated ML385 partly abolished all these effects of Anwulignan. Anwulignan protects the liver from damage in the exhausted mice by its antioxidant effects and related to its activation of the NRF2 pathway.

7.
Neurosci Lett ; 692: 225-230, 2019 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-30290247

RESUMO

Previous behavioral studies have shown that high-intensity cognitive tasks weaken balance control in elder adults. Moreover, age-related loss of plantar sensation is considered to be an important contributing factor to the occurrence of falls. Recently, we have realized that transcranial direct current stimulation (tDCS) can effectively improve the balance of the elderly under the dual-task, but its underlying regulatory mechanism is not clear. In this study, task functional Magnetic Resonance Imaging (fMRI) was used to study the brain's response to foot stimuli under foot stimuli or dual-task (foot stimuli and cognitive task) conditions to explain the effect of the addition of cognitive tasks during balance in 16 healthy elderly adults. To study whether tDCS would counteract the effect of the added cognitive task, we further compared the differences in activity of the cerebral cortices of dual-task and tDCS-dual-task conditions. The results suggested added cognitive tasks significantly attenuated the response of the brain to foot stimuli in elderly adults. Moreover, the cortex excitability weakened by cognitive tasks was significantly promoted after 20 min of tDCS. In conclusion, a portion of the resources originally used for plantar sensory processing may be assigned to the processing of the cognitive task when the cognitive tasks are added, which results in insufficient resources for plantar sensory processing. tDCS improves the ability of the brain to respond to foot stimuli by modulating the excitability of the cognitive cortex and reverses the effects of cognitive tasks.


Assuntos
Encéfalo/fisiologia , Cognição , Pé/fisiologia , Equilíbrio Postural , Desempenho Psicomotor , Idoso , Excitabilidade Cortical , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estimulação Física , Córtex Somatossensorial/fisiologia , Tato , Percepção do Tato/fisiologia , Estimulação Transcraniana por Corrente Contínua
8.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-692956

RESUMO

Objective To investigate the correlation betw een serum 25-hydroxyvitamin D (25(OH) D) level and enlarged perivascular spaces (EPVS) in patients w ith lacunar infarction. Methods Consecutive inpatients w ith acute lacunar infarction w ere enrolled. Chemiluminescence immunoassay w as used to measure the serum 25(OH)D. Head MRI w as used to assess the severity of EPVS in the centrum ovale and the basal ganglia region (grade 1, 0-10; grade 2, 11-25; grade 3, >25). Univariate analysis w as used to analyze the differences in baseline data among the three groups. Multivariate ordinal logistic regression analysis w as used to investigate the independent correlation betw een the 25(OH)D levels and the severity of EPVS. Results A total of 194 patients w ere enrolled,96 w ere males.Their mean age w as 63.4 ±9.3 years. The mean baseline National Institutes of Health Stroke Scale (NIHSS) score w as 2.0 ±1.7. The mean 25(OH)D level w as(50.25 ±15.50)nmol/L. There w ere 112 patients (57.7%), 45 (23.2%) and 37 (19.1%) w ith EPVS grade 1,grade 2 and grade 3 in the centrum ovale,and 109 (56.2%),53(27.3%) and 32 (16.5%) w ith EPVS grade 1, grade 2 and grade 3 in basal ganglia region, respectively. Multivariate ordinal logistic regression analysis show ed that serum 25(OH)D levels w ere independently associated w ith the severity of EPVS in the centrum ovale (odds ratio 2.898,95% confidence interval 1.345-9.612; P=0.028) and basal ganglia region (odds ratio 2.688, 95% confidence interval 1.182-10.281; P=0.039). Conclusion The low serum 25 (OH) D levels are independently associated w ith the severity of EPVS in patients w ith lacunar infarction.

9.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-271884

RESUMO

<p><b>OBJECTIVE</b>To investigate the effect of transcriptional regulation of aberrant transcription factor AML1-ETO on p14.</p><p><b>METHODS</b>P14expression both in AML1-ETO-expressing cells or U937 nonexpressing cells and in leukemia cells of AML patients with or without t(8;21) was assessed by quantitative PCR. Methylation-specific polymerase chain reaction (MSP) was used to analyze the methylation status of p14promoter. The chromatin immunoprecipitation (ChIP)-based PCR was used to investigate the direct interaction between the AML1-ETO and p14promoter in AML1-ETO positive leukemia cell line. And the p14mRNA expression level was detected by qRT-PCR after treatment with 5-Aza.</p><p><b>RESULTS</b>AML1-ETO-expressing cell subclone displayed low level of p14mRNA in comparison with the non-transfected U937. In primary bone marrow cells of acute myeloid leukemia containing AML1-ETO, level of p14mRNA was markedly lower when compared with other acute myeloid leukemias lacking this translocation. P14gene promoter was non-methylated in control group and primary leukemia cells of AML patients without t(8;21) and was hyper-methylated in U937-A/E1-4 and primary leukemia cells of AML patients with t(8;21). The enriched regions in transfected cells were located within p14promoter. 5-Aza could increase the expression of p14.</p><p><b>CONCLUSION</b>P14is a possible target gene of AML1-ETO. The p14silencing induced by hyper-methlylation may be an important factor for occurrence and development of the Msubtype of acute myeloid leukemia.</p>

10.
The Journal of Practical Medicine ; (24): 1864-1866, 2014.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-453035

RESUMO

Objective To investigate the effect of EGB on SOD, MDA of ventilator-induced lung injury in rats and its possible mechanisms. Methods Thirty male SD rats were randomly divided into 3 groups: control group (C group), high tidal ventilation group (H group) and EGB group (E group). The setting mechanical ventilation was VT=30 mL/kg, RR=40/min, I/E=1/3, PEEP=0 cmH2 O and FiO2=21%. The broncho-alveolar lavage fluid (BLAF) and serum were obtained for determination of the levels of SOD and MDA at the end of 4 h mechanical ventilation. The Lungs were removed, and the wet-to-dry weight ratio (W/D) and pulmonary pathologic changes were measured. Results As compared with C group, W/D and the levels of MDA were significantly increased in H group, but the levels of SOD were reduced in H group. As compared with H group, W/D and the levels of MDA were significantly decreased in E group, but the levels of SOD were increased in E group. Pulmonary pathologic changes were alleviated in E group comparing with H group. Conclusion EGB injection may have a protective role against hyperoxia and induced pulmonary damage in rats.

11.
Journal of Experimental Hematology ; (6): 1394-1398, 2013.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-265006

RESUMO

This study was aimed to investigate the effect of AML1-ETO fusion protein on the anti-apoptotic gene BCL-2 in leukemic cells and to explore its role in leukemogenesis. The apoptotic levels of U937-WT, U937-Mock and U937-A/E1-4 cells were examined by flow cytometry. And cleaved caspase-3 protein expression was detected by Western blot. BCL-2 gene expression both in AML1-ETO-expressing cells or U937 nonexpressing cells and in leukemia cells of AML patients with or without t(8;21) was assessed by quantitative PCR. The chromatin immunoprecipitation (ChIP)-based PCR was used to investigate the direct interaction between the AML1-ETO and BCL-2 promoter in AML1-ETO positive leukemia cell line. The results indicated that in U937-A/E cells but not in U937-WT or U937-Mock cells, apoptotic cells statistically significantly increased, and AML1-ETO expression also significantly enhanced activation of caspase-3. AML1-ETO-expressing cell subclones displayed significantly low levels of BCL-2 mRNA in comparison with the non-transfected U937. In primary bone marrow cells of acute myeloid leukemia containing AML1-ETO, levels of BCL-2 mRNA were markedly lower as compared with other acute myeloid leukemias lacking this translocation. The enriched regions in transfected cells were located within BCL-2 promoter. It is concluded that BCL-2 is the direct target gene of AML1-ETO. AML1-ETO can down-regulate the expression of BCL-2.


Assuntos
Humanos , Subunidade alfa 2 de Fator de Ligação ao Core , Genética , Metabolismo , Regulação Leucêmica da Expressão Gênica , Leucemia Mieloide Aguda , Genética , Metabolismo , Proteínas de Fusão Oncogênica , Genética , Metabolismo , Proteínas Proto-Oncogênicas c-bcl-2 , Metabolismo , Proteína 1 Parceira de Translocação de RUNX1 , Células U937
12.
Chinese Journal of Hematology ; (12): 373-377, 2011.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-251947

RESUMO

<p><b>OBJECTIVE</b>To construct a pcDNA3.1-AML1-ETO expression vector and investigate its effects on proliferation and differentiation of U937 leukemic cells.</p><p><b>METHODS</b>AML1-ETO gene was amplified by PCR from pCMV5-AML1-ETO and inserted into eukaryotic expression plasmid pcDNA3.1/V5-His-TOPO. The recombinant plasmid was transfected into U937 cells by Lipofectamin 2000. Individual clones selected with G418 were isolated. The integration and the expression levels of AML1-ETO in transfectants were determined by PCR, RT-PCR and Western blot analysis respectively. Trypan blue refusal staining method was used to detect the proliferation of U937 cells. Light microscope was applied to observe the morphologic changes of the cell. The expression of myeloid cell differentiation antigen was detected using flow cytometry.</p><p><b>RESULTS</b>The recombinant pcDNA3.1-AML1-ETO was confirmed by enzyme digestion and sequencing. The highly expressing AML1-ETO subclone was established. AML1-ETO was expressed in U937 cells transfected with pcDNA3.1-AML1-ETO. The growth of the monoclonal cells was inhibited evidently (P < 0.05). The expression of CD11b in transfected group \[(4.17 ± 0.31)%\] was lower than that in empty plasmid transfected group and non-transfected group \[(11.40 ± 0.17)% and (11.03 ± 0.15)%\] respectively (P < 0.001). Transfected cells displayed morphology of less differentiation. The expression level of CDl1b was unchanged in transfected cells treated with TPA (P > 0.05).</p><p><b>CONCLUSION</b>The eukaryotic expression vector for AML1-ETO gene was successfully constructed and expressed in U937. AML1-ETO inhibits the proliferation and differentiation of transfected cells. It provides the basis for further study of mechanisms of AML1-ETO in leukemogenesis.</p>


Assuntos
Humanos , Diferenciação Celular , Proliferação de Células , Subunidade alfa 2 de Fator de Ligação ao Core , Genética , Expressão Gênica , Vetores Genéticos , Leucemia , Genética , Patologia , Proteínas de Fusão Oncogênica , Genética , Plasmídeos , Proteína 1 Parceira de Translocação de RUNX1 , Células U937
13.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 1): m45-6, 2008 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-21581517

RESUMO

In the title compound, [Cu(C(6)H(3)BrNO(2))(2)(H(2)O)], the Cu atom adopts a distorted trigonal-bipyramidal coordination arising from two N,O-bidentate ligands and a water mol-ecule, with one N atom in an axial site and the other in an equatorial site. The dihedral angle between the pyridine ring planes is 67.6 (2)°. In the crystal, O-H⋯O hydrogen bonds result in chains propagating in [100].

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