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1.
Molecules ; 24(1)2019 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-30609723

RESUMEN

Ultrasonic-microwave assisted extraction (UMAE) of Trametes orientalis polysaccharides was optimized by response surface methodology. Hepatoprotective effects of a purified T. orientalis polysaccharide (TOP-2) were evaluated by alcohol-induced liver injury model mice. The optimal UMAE parameters were indicated as below: ratio of water to raw material 28 mL/g, microwave power 114 W, extraction time 11 min. The polysaccharides yield was 7.52 ± 0.12%, which was well consistent with the predicted value of 7.54%. Pre-treatment with TOP-2 effectively increased the liver index and spleen index in alcohol-treated mice. The elevated serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels of mice after alcohol exposure were inhibited by TOP-2 administration. The liver tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß) levels have decreased significantly as a result of alcohol exposure, while pre-treatment with TOP-2 could mitigate these consequences. Furthermore, pre-treatment with TOP-2 could efficiently boost the superoxidase dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) activities, and observably constrain the malondialdehyde (MDA) level. The findings suggest that TOP-2 might be useful for alleviating the alcohol-induced hepatotoxicity via its antioxidant and anti-inflammatory potential.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas/prevención & control , Microondas , Polisacáridos/farmacología , Trametes/química , Ultrasonido/métodos , Alanina Transaminasa/sangre , Animales , Antioxidantes/aislamiento & purificación , Antioxidantes/farmacología , Aspartato Aminotransferasas/sangre , Descubrimiento de Drogas , Etanol/toxicidad , Interleucina-1beta/metabolismo , Hígado/efectos de los fármacos , Masculino , Malondialdehído/metabolismo , Ratones , Estrés Oxidativo/efectos de los fármacos , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Polisacáridos/aislamiento & purificación , Transducción de Señal , Factor de Necrosis Tumoral alfa/metabolismo
2.
Mass Spectrom Rev ; 36(4): 543-579, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-27074547

RESUMEN

Coal-derived liquids (CDLs) are primarily generated from pyrolysis, carbonization, gasification, direct liquefaction, low-temperature extraction, thermal dissolution, and mild oxidation. CDLs are important feedstocks for producing value-added chemicals and clean liquid fuels as well as high performance carbon materials. Accordingly, the compositional characterization of chemicals in CDLs at the molecular level with advanced analytical techniques is significant for the efficient utilization of CDLs. Although reviews on advancements have been rarely reported, great progress has been achieved in this area by using gas chromatography/mass spectrometry (GC/MS), two-dimensional GC-time of flight mass spectrometry (GC × GC-TOFMS), and Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). This review focuses on characterizing hydrocarbon, oxygen-containing, nitrogen-containing, sulfur-containing, and halogen-containing chemicals in various CDLs with these three mass spectrometry techniques. Small molecular (< 500 u), volatile and semi-volatile, and less polar chemicals in CDLs have been identified with GC/MS and GC × GC-TOFMS. By equipped with two-dimensional GC, GC × GC-TOFMS can achieve a clearly chromatographic separation of complex chemicals in CDLs without prior fractionation, and thus can overcome the disadvantages of co-elution and serious peak overlap in GC/MS analysis, providing much more compositional information. With ultrahigh resolving power and mass accuracy, FT-ICR MS reveals a huge number of compositionally distinct compounds assigned to various chemical classes in CDLs. It shows excellent performance in resolving and characterizing higher-molecular, less volatile, and polar chemicals that cannot be detected by GC/MS and GC × GC-TOFMS. The application of GC × GC-TOFMS and FT-ICR MS to chemical characterization of CDLs is not as prevalent as that of petroleum and largely remains to be developed in many respects. © 2016 Wiley Periodicals, Inc. Mass Spec Rev 36:543-579, 2017.

3.
Rapid Commun Mass Spectrom ; 32(17): 1521-1528, 2018 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-29729046

RESUMEN

RATIONALE: Coal oxidation produces carboxylic acids (CAs), including aliphatic acids, benzoic acids, and benzenepolycarboxylic acids, which are important fine chemicals which could be used to understand the structural features of coals. However, detecting CAs usually presents great challenges due to extremely troublesome pretreatments. Therefore, it is essential to develop an analytical method for the rapid detection of CAs from coal oxidation. METHODS: A series of model compounds (MCs) of oxidation products and two practical samples were investigated by direct analysis in real time time-of-flight mass spectrometry (DART-TOFMS) under three different analytical conditions (ionizing gas temperature, organic solvent, and MC concentration). RESULTS: Ionizing methyl benzoate, dimethyl phthalate, and dimethyl adipate produces typical ions of methyl esters, including [M - OCH3 ]+ , [M + H]+ , and [M + NH4 ]+ . In contrast, the characteristic ions generated from CAs are polymer ions, such as [2 M + NH4 ]+ , [3 M + NH4 ]+ , [4 M + NH4 ]+ , and [5 M + NH4 ]+ , indicating the strong intermolecular hydrogen-bond interaction among CAs. CONCLUSIONS: Results suggest that DART-TOFMS could rapidly analyze CAs or esters in coal oxidation products according to their typical ions to further gain deep insights into the coal structure.

4.
Water Sci Technol ; 74(1): 229-35, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27387001

RESUMEN

In this study, Zn/Al-layered double hydroxides (Zn/Al-LDHs) were synthesized by a co-precipitation method and characterized with X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy. Then the hexavalent chromium Cr(VI) adsorption experiments on calcined Zn/Al-LDHs were carried out to analyze the effects of pH, temperature, adsorption time, initial Cr(VI) concentration and adsorbent dosage on the removal of Cr(VI) from aqueous solutions. The maximum adsorption capacity for Cr(VI) on calcined Zn/Al-LDHs under optimal conditions was found to be over 120 mg/g. The kinetic and isotherm of Cr(VI) adsorption on calcined Zn/Al-LDHs can be described with the pseudo-second-order kinetic model and Langmuir isotherm, respectively.


Asunto(s)
Cromo/química , Hidróxidos/química , Polímeros/química , Contaminantes Químicos del Agua/química , Zinc/química , Adsorción , Cinética , Polímeros/síntesis química , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Difracción de Rayos X
5.
Org Lett ; 26(6): 1271-1276, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38323795

RESUMEN

A novel and highly selective electrochemical method for the synthesis of diverse quinazolinone oximes via direct electrooxidation of primary amines/C(sp2)-H functionalization of oximes has been developed. The reaction is conducted in an undivided cell under constant current conditions and is oxidant-free, open-air, and eco-friendly. Notably, the protocol shows good functional group tolerance, providing versatile quinazolinone oximes in good yields. Moreover, the mechanism is investigated through control experiments and cyclic voltammogram (CV) experiments.

6.
J Chromatogr A ; 1603: 160-164, 2019 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-31272732

RESUMEN

An environmentally benign and cost-effective method was designed for isolating and purifying condensed arenes from acetone-extractable portion (AEP) of a high-temperature coal tar through a high pressure preparative chromatograph (HPPC) with different packings, including silica gel, octadecyl silane, octyl bonded silica gel, and diol bonded silica gel. In total, 196 compounds were detected with a gas chromatograph/mass spectrometer from AEP and its eluates. From the eluates, naphthalene, anthracene, phenanthrene, fluoranthene, and pyrene were successfully isolated and purified, and their structures were confirmed by their 1H and 13C nuclear magnetic resonance spectra in addition to their mass spectra. Extraction-HPPC device and solvent recovery process were designed and developed, which can potentially be applied to industrial production because the process is easy-to-operate and ecofriendliness. In addition, the solvents used can be easily recovered and reused, and neither waste water nor other pollutions are emitted.


Asunto(s)
Alquitrán/química , Cromatografía de Gases y Espectrometría de Masas/métodos , Calor , Hidrocarburos Policíclicos Aromáticos/aislamiento & purificación , Presión , Antracenos/aislamiento & purificación , Fluorenos/aislamiento & purificación , Naftalenos/aislamiento & purificación , Fenantrenos/aislamiento & purificación , Pirenos/aislamiento & purificación
7.
Biomaterials ; 184: 20-30, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30195802

RESUMEN

Successful immunogene therapy depends not only on the therapeutic gene but also on the gene delivery vector. In this study, we synthesized a novel copolymer consisting of low-molecular-weight polyethylenimine (PEI) cross-linked by myo-inositol (INO) and conjugated with a galactose-grafted PEG chain, named LA-PegPI. We characterized the chemical structure and molecular weight of the copolymer and particle properties of LA-PegPI/pDNA. Furthermore, we showed that LA-PegPI/pDNA polyplexes possessed excellent stability in physiological salt solution, low cytotoxicity, and high transfection efficiency in the asialoglycoprotein receptor (ASGPR)-positive liver cells in vitro. Importantly, we also showed that through intraperitoneal injection of LA-PegPI/pDNA nanoparticles, the reporter gene was forcefully expressed in the liver hepatocytes of mice. Finally, we documented that intraperitoneal injection of LA-PegPI/pIL15 nanoparticles effectively suppressed tumor growth and prolonged survival time of tumor-bearing mice via activation of CD8+ T cells and NK cells and upregulation of the cytokines IFN-γ, TNF, and IL12 in an orthotopic hepatocellular carcinoma mouse model. Interestingly, LA-PegPI/pluc nanoparticles could effectively stimulate the proliferation of NK cells and inhibit tumor growth in this model. In summary, LA-PegPI is a useful gene vector for immunogene therapy of hepatocellular carcinoma, and its potential for clinical application warrants further study.


Asunto(s)
Receptor de Asialoglicoproteína/genética , Carcinoma Hepatocelular/terapia , Galactosa/química , Interleucina-15/metabolismo , Neoplasias Hepáticas/terapia , Polietilenglicoles/química , Animales , Carcinoma Hepatocelular/inmunología , Carcinoma Hepatocelular/metabolismo , Línea Celular Tumoral , Reactivos de Enlaces Cruzados/química , ADN/administración & dosificación , Portadores de Fármacos , Femenino , Genes Reporteros , Hepatocitos/patología , Humanos , Inmunoterapia , Inositol/química , Interleucina-15/genética , Neoplasias Hepáticas/inmunología , Neoplasias Hepáticas/metabolismo , Ratones Endogámicos BALB C , Peso Molecular , Nanopartículas/química , Plásmidos , Polietileneimina/química
8.
Int J Biol Macromol ; 95: 1216-1222, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27825995

RESUMEN

The present study evaluated the ameliorative effects of Trametes orientalis polysaccharide (TOP-2) against cyclophosphamide (CP) induced toxicity in mice. Intraperitoneal administration of TOP-2 not only effectively increased the thymus, spleen, heart, liver, and kidney indices, but also significantly enhanced the phagocytic activities of macrophages and splenocyte proliferation, dose-dependently. The lowered nitric oxide level of macrophages after CP treatment was elevated by TOP-2 administration. Impaired splenic natural killer cells and cytotoxic T lymphocytes activities were remarkably enhanced by TOP-2. Furthermore, the levels of interleukin-2, interferon-γ, Immunoglobulin A, immunoglobulin G, and immunoglobulin M were notably reduced by CP, while TOP-2 abolished these effects. TOP-2 could also effectively increase the total antioxidant capacity, superoxidase dismutase, catalase and glutathione peroxidase activities, and inhibit the increase in malondialdehyde level. These results indicate that TOP-2 may be of therapeutic value in ameliorating the immunosuppression and oxidative stress caused by CP treatment, through its immunomodulatory and antioxidant potential.


Asunto(s)
Antiinflamatorios/farmacología , Antioxidantes/farmacología , Ciclofosfamida/antagonistas & inhibidores , Polisacáridos Fúngicos/farmacología , Inmunosupresores/antagonistas & inhibidores , Trametes/química , Animales , Antiinflamatorios/química , Antiinflamatorios/aislamiento & purificación , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Catalasa/inmunología , Catalasa/metabolismo , Ciclofosfamida/efectos adversos , Femenino , Polisacáridos Fúngicos/química , Polisacáridos Fúngicos/aislamiento & purificación , Glutatión Peroxidasa/inmunología , Glutatión Peroxidasa/metabolismo , Corazón/efectos de los fármacos , Terapia de Inmunosupresión , Inmunosupresores/efectos adversos , Riñón/efectos de los fármacos , Riñón/inmunología , Células Asesinas Naturales/efectos de los fármacos , Células Asesinas Naturales/inmunología , Hígado/efectos de los fármacos , Hígado/inmunología , Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Masculino , Malondialdehído/inmunología , Malondialdehído/metabolismo , Ratones , Estrés Oxidativo/efectos de los fármacos , Fagocitosis/efectos de los fármacos , Bazo/efectos de los fármacos , Bazo/inmunología , Superóxido Dismutasa/inmunología , Superóxido Dismutasa/metabolismo , Linfocitos T Citotóxicos/efectos de los fármacos , Linfocitos T Citotóxicos/inmunología , Timo/efectos de los fármacos , Timo/inmunología
9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 23(1): 192-3, 2003 Feb.
Artículo en Zh | MEDLINE | ID: mdl-12940005

RESUMEN

The structure of 1, 1'-and 1, 2'-dinaphthyl methanone synthesized by the reaction of naphthalene with oxalyl chloride in the presence of AlCl3 were studied by using UV and FTIR in this paper. The analysis results showed that the difference of structures (symmetry) of 1,1'-and 1, 2'-dinaphthyl methanone were represented on the obvious difference of the spectra of UV and FTIR.


Asunto(s)
Naftalenos/química , Protectores Solares/química , Estructura Molecular , Espectrofotometría Infrarroja , Espectrofotometría Ultravioleta
10.
Nanoscale ; 6(11): 6075-83, 2014 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-24781354

RESUMEN

A facile bottom-up strategy was developed to fabricate nitrogen-doped graphene sheets (NGSs) from glucose using a sacrificial template synthesis method. Three main types of nitrogen dopants (pyridinic, pyrrolic and graphitic nitrogens) were introduced into the graphene lattice, and an inimitable microporous structure of NGS with a high specific surface area of 504 m(2) g(-1) was obtained. Particularly, with hybrid features of lithium ion batteries and Faradic capacitors at a low rate and features of Faradic capacitors at a high rate, the NGS presents a superior lithium storage performance. During electrochemical cycling, the NGS electrode afforded an enhanced reversible capacity of 832.4 mA h g(-1) at 100 mA g(-1) and an excellent cycling stability of 750.7 mA h g(-1) after 108 discharge-charge cycles. Furthermore, an astonishing rate capability of 333 mA h g(-1) at 10,000 mA g(-1) and a high rate cycle performance of 280.6 mA h g(-1) even after 1200 cycles were also achieved, highlighting the significance of nitrogen doping on the maximum utilization of graphene-based materials for advanced lithium storage.

11.
Microsc Res Tech ; 76(7): 744-50, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23650075

RESUMEN

Infrared light from a pulsed optical parametric oscillator laser system was used to irradiate succinic acid (SA), a usual solid matrix used in matrix-assisted laser desorption ionization, under vacuum. Ablated SA particles were trapped using a silica plate mounted 3.0 mm above and parallel to the sample surface. The morphology and particle size of ablated particles at different laser fluences were investigated using a scanning electron microscope (SEM). The dynamics of plume propagation for SA desorption process was studied with fast photography at atmospheric pressure. Plume expanding at 1.12 J/cm(2) laser fluence was recorded using a high-speed CMOS camera and corresponding propagation distance was measured. The solid matrix desorption was driven by phase explosion according to plume model fitting, which was consistent with the results of SEM.

12.
Bioresour Technol ; 142: 504-9, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23765001

RESUMEN

Pine liquefaction (PL) and re-liquefaction of its liquefaction residues in sub- and supercritical methanol, water or methanol/water mixed solvents (MWMSs) was investigated. The results show that isometric MWMS has the highest synergic effect on PL. Moreover, the total yield of bio-oil (BO) and conversion from pine and its residue both liquefied in the MWMS were obvious higher than those from PL in methanol (water) and re-liquefaction of its residue in water (methanol), suggesting that the interaction between the two solvents is responsible for synergic effect. This approach facilitates understanding the mechanism for biomass liquefaction in mixed solvents and developing efficient utilization process of biomass.


Asunto(s)
Metanol/química , Pinus , Agua/química , Biomasa , Cinética , Solventes/química , Temperatura
13.
Brain Res ; 1429: 1-8, 2012 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-22088822

RESUMEN

Although previous researches indicated that heme oxygenase-1 (HO-1) plays a conspicuous role in neuronal injury induced by reperfusion following the brain ischemia, reasonable mechanisms for the role of HO-1 are not clear. In this work, we investigated whether HO-1 was involved in the regulation of the c-Jun N-terminal kinase (JNK) signaling pathway and neuronal cell injury induced by the brain ischemia followed by reperfusion. Cobaltic protoporphyrin (CoPP), an activator of HO-1, was administrated to induce the overexpression of HO-1 by intracerebroventricular infusion 20 min before ischemia. The results showed that the combination of HO-1-mixed lineage kinase 3 (MLK3), MLK3-mitogen-activated kinase kinase 7 (MKK7) and MKK7-JNK3 increased to a peak at 6h of reperfusion following 15 min of ischemia induced by four-vessel occlusion in rats, and these effects were downregulated by CoPP. In addition, CoPP could inhibit the activation of JNK3, c-Jun and caspase-3. Furthermore, pretreatment with CoPP significantly increased the survival of neurons after 5 days of reperfusion. In contrast, all of the above effects of CoPP were reversed by zinc protoporphyrin (ZnPP), a selective inhibitor of HO-1. Our results suggested that HO-1 could protect neurons against brain ischemic injury by downregulating the JNK signaling pathway through the MLK3-MKK7-JNK3 signaling module.


Asunto(s)
Isquemia Encefálica/enzimología , Hemo Oxigenasa (Desciclizante)/metabolismo , Sistema de Señalización de MAP Quinasas/fisiología , Daño por Reperfusión/enzimología , Animales , Isquemia Encefálica/patología , Immunoblotting , Inmunoprecipitación , Etiquetado Corte-Fin in Situ , MAP Quinasa Quinasa 7/metabolismo , Quinasas Quinasa Quinasa PAM/metabolismo , Masculino , Proteína Quinasa 10 Activada por Mitógenos/metabolismo , Ratas , Ratas Sprague-Dawley , Daño por Reperfusión/patología , Proteina Quinasa Quinasa Quinasa 11 Activada por Mitógeno
14.
Bioresour Technol ; 116: 114-9, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22609664

RESUMEN

Detailed compositional analysis of a bio-oil (BO) from pyrolysis of rice husk was carried out. The BO was extracted sequentially with n-hexane, CCl(4), CS(2), benzene and CH(2)Cl(2). In total, 167 organic species were identified with GC/MS in the extracts and classified into alkanes, alcohols, hydroxybenzenes, alkoxybenzenes, dioxolanes, aldehydes, ketones, carboxylic acids, esters, nitrogen-containing organic compounds and other species. The benzene ring-containing species (BRCCs) were attributed to the degradation of lignin while most of the rests were derived from the degradation of cellulose and hemicellulose. Along with guaiacyl and p-hydroxyphenyl units as the main components, a new type of linkage was suggested, i.e., C(ar)-CH(2)-C(ar) in 4,4'-methylenebis(2,6-dimethoxyphenol). Based on the species identified, a possible macromolecular structure of the lignin and the mechanism for its pyrolysis are proposed. The BO was also extracted with petroleum ether in ca. 17.8% of the extract yield and about 82.1% of the extracted components are BRCCs.


Asunto(s)
Biocombustibles/análisis , Biotecnología/métodos , Lignina/química , Oryza/química , Aceites de Plantas/análisis , Temperatura , Residuos/análisis , Alcanos/química , Compuestos Orgánicos/análisis , Extractos Vegetales/química
15.
Acta Crystallogr C ; 61(Pt 12): m542-4, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16330843

RESUMEN

In the title one-dimensional complex, [[Mn(III)(C9H10NO2)2]Cl]n, the Schiff base ligand 2-[(2-hydroxyethyl)iminomethyl]phenolate (Hsae-) functions as both a bridging and a chelating ligand. The Mn(III) ion is six-coordinated by two N and four O atoms from four different Hsae- ligands, yielding a distorted MnO4N2 octahedral environment. Each [Mn(III)(Hsae)2]+ cationic unit has the Mn atom on an inversion centre and each [Mn(III)(Hsae)2]+ cation lies about another inversion centre. The chain-like complex is further extended into a three-dimensional network structure through Cl...H-O hydrogen bonds and C-H...pi contacts involving the Hsae- rings.

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