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1.
Inorg Chem ; 63(26): 12281-12289, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38902887

RESUMO

The synergistic effect between multicomponent electrode materials often makes them have better lithium storage performance than single-component electrode materials. Therefore, to enhance surface reaction kinetics and encourage electron transfer, using multicomponent anode materials is a useful tactic for achieving high lithium-ion battery performance. In this article, ZnS/ZnO composites were synthesized by solvothermal sulfidation and calcination, with the utilization of metal-organic frameworks acting as sacrificial templates. From the point of material design, both ZnS and ZnO have high theoretical specific capacities, and the synergistic effect of ZnS and ZnO can promote charge transport. From the perspective of electrode engineering, the loose porous carbon skeleton that results from the calcination of metal-organic frameworks can enhance composite material conductivity as well as full electrolyte penetration and the area of contact between the electrolyte and active material, all of which are beneficial to enhancing lithium storage performance. As expected, ZnS/ZnO anode materials displayed remarkably high specific capacities and outstanding performance at different rates. Combining material design and electrode engineering, this paper provides another idea for preparing anode materials with excellent lithium storage properties.

2.
Chemistry ; 23(15): 3542-3547, 2017 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-28094459

RESUMO

Two analogous M4 L4 -type tetrahedral cages (smaller: MOC-19; larger: MOC-22) were synthesized and investigated for their interactions with the anticancer drug 5-fluoracil (5-FU) by NMR spectroscopy, high-resolution electrospray-ionization mass spectrometry (HR-ESI-MS), and molecular simulation. The cage's size and window are of importance for the host-guest binding, and consequently the smaller MOC-19 with a more suitable size of cavity window was found to have much stronger hydrogen-bond interactions with 5-FU. The porous nanoparticles of MOC-19 exhibited outstanding behavior for the controlled release of 5-FU in a simulated human body with liquid phosphate-buffered saline solution.


Assuntos
Antineoplásicos/administração & dosagem , Preparações de Ação Retardada/química , Fluoruracila/administração & dosagem , Estruturas Metalorgânicas/química , Antineoplásicos/química , Fluoruracila/química , Ligação de Hidrogênio , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Nanopartículas/química , Tamanho da Partícula , Porosidade , Espectrometria de Massas por Ionização por Electrospray
3.
Anal Bioanal Chem ; 409(22): 5239-5247, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28685174

RESUMO

The fiber coating is the key part of the solid-phase microextraction (SPME) technique, and it determines the sensitivity, selectivity, and repeatability of the analytical method. In this work, amine (NH2)-functionalized material of Institute Lavoisier (MIL)-53(Al) nanoparticles were successfully synthesized, characterized, and applied as the SPME fiber coating for efficient sample pretreatment owing to their unique structures and excellent adsorption properties. Under optimized conditions, the NH2-MIL-53(Al)-coated fiber showed good precision, low limits of detection (LODs) [0.025-0.83 ng L-1 for synthetic musks (SMs) and 0.051-0.97 ng L-1 for organochlorine pesticides (OCPs)], and good linearity. Experimental results showed that the NH2-MIL-53(Al) SPME coating was solvent resistant and thermostable. In addition, the extraction efficiencies of the NH2-MIL-53(Al) coating for SMs and OCPs were higher than those of commercially available SPME fiber coatings such as polydimethylsiloxane, polydimethylsiloxane-divinylbenzene, and polyacrylate. The reasons may be that the analytes are adsorbed on NH2-MIL-53(Al) primarily through π-π interactions, electron donor-electron acceptor interactions, and hydrogen bonds between the analytes and organic linkers of the material. Direct immersion (DI) SPME-gas chromatography-mass spectrometry methods based on NH2-MIL-53(Al) were successfully applied for the analysis of tap and river water samples. The recoveries were 80.3-115% for SMs and 77.4-117% for OCPs. These results indicate that the NH2-MIL-53(Al) coating may be a promising alternative to SPME coatings for the enrichment of SMs and OCPs.

4.
J Nerv Ment Dis ; 204(6): 479-82, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26915018

RESUMO

This retrospective study recruited 150 patients with recurrent major depressive disorder (MDD) who received modified electroconvulsive therapy (MECT) and 150 cases treated with repetitive transcranial magnetic stimulation (rTMS), which aimed to compare the short- and long-term effectiveness, as well as economic outcomes, of MECT and rTMS with a large sample size in patients with recurrent MDD. The results showed that the response rate of patients in the rTMS group was lower than that in the MECT group (46.0% vs 58.7%, p < 0.05). Patients in the rTMS group had elevated rate of dizziness, but reduced rates of poor memory and headache, as well as lower costs compared with the MECT group (p < 0.05). Importantly, we found that the relapse-free survival of patients was similar between the rTMS and MECT groups in the long term. In conclusion, rTMS is an alternative method for MECT in the treatment of patients with recurrent MDD.


Assuntos
Transtorno Depressivo Maior/diagnóstico , Transtorno Depressivo Maior/terapia , Eletroconvulsoterapia/métodos , Estimulação Magnética Transcraniana/métodos , Adulto , Idoso , Transtorno Depressivo Maior/psicologia , Eletroconvulsoterapia/tendências , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Fatores de Tempo , Estimulação Magnética Transcraniana/tendências , Resultado do Tratamento , Adulto Jovem
5.
Food Funct ; 14(9): 4267-4279, 2023 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-37070224

RESUMO

In this study, two pectic polysaccharides from fresh and dried Dendrobium officinale, namely FDP and DDP, were obtained by sour-water extraction, ethanol precipitation and further purification with DEAE cellulose-52 and Sephadex G-100 column chromatography. FDP/DDP had eight similar glycosidic linkages including 1,4-linked-GlcAp, 1,4- and 1,3,4-linked-GalAp, 1,3,4- and T-linked-Glcp, 1,6- and T-linked-Galp, T-linked-Galp and T-linked-Xylp. Besides, FDP was marked by 1,6-, 1,2,6-linked-Manp and 1,2,4-, 1,2-linked-Rhap, and DDP consisted of unique 1,6-linked-GlcAp and 1,3,6-Manp. FDP with a molecular weight of 14.8 kDa generally showed stronger scavenging capacity against DPPH, ABTS and hydroxyl radicals than DDP (p < 0.05). Pretreatment with FDP/DDP alleviated the alcohol-induced liver injury in mice, and their serum aminotransferase and triglyceride levels were 10.3%-57.8% lower than those of the model group (MG). Meanwhile, the FDP/DDP-M and FDP/DDP-H groups (200 and 300 mg kg-1) displayed a remarkable increase in antioxidant enzyme activities and significant reduction in inflammatory cytokine levels in comparison with the MG. Further analysis revealed that FDP-treated mice generally exhibited lower transaminase levels and inflammatory cytokine expression as well as higher antioxidant enzyme activities than DDP-treated ones. The FDP-H group showed significant restoration, which was slightly less than or almost comparable to that of the bifendate-fed positive control. The above results indicate that D. officinale pectin can attenuate oxidative stress and inflammatory cytokine response, and ultimately ameliorate liver injury, and "fresh" pectin with specific structural characteristics is expected to be more promising as hepatoprotective food.


Assuntos
Dendrobium , Pectinas , Camundongos , Animais , Antioxidantes/química , Dendrobium/química , Polissacarídeos/química , Etanol , Fígado , Citocinas
7.
Psychol Res Behav Manag ; 15: 2683-2689, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36160273

RESUMO

Background/Objectives: Neurosyphilis is a disease caused by Treponema pallidum when it invades the central nervous system. Asymptomatic neurosyphilis (ANS) is one of the most common types of neurosyphilis, however it is often misdiagnosed. This study aimed to explore the impact of ANS on patient's quality of life and social stigma. Methods: A total of 159 ANS patients were diagnosed by their serology and cerebrospinal fluid. These patients' stigma and quality of life were assessed separately through the Social Impact Scale (SIS) and the Easy Response Questionnaire. Results: The average age was 36.25±8.36 years old, and 114 patients were males (71.69%). The serum syphilis test of 159 selected patients was positive, and the indicators of nucleus cells, protein quantification, and syphilis antibodies in the cerebrospinal fluid met the criteria for ANS. The total stigma score was (40.23 ±10.12), with the scores of the different entries being clearly differentiated, with the highest being the 15th entry (I feel I need to keep my illness a secret), with an average score of 3.15/4. Conclusion: Patients with asymptomatic neurosyphilis may feel social stigma and are more negative when facing their disease. Health-care workers should be aware of the particular aspects of their condition and pay special attention to the need for patient privacy.

8.
Chem Asian J ; 11(2): 216-20, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26541782

RESUMO

An M(4) L4 type metal-organic cage (MOC-19) has been synthesized from the one-pot reaction of tri(pyridinylmethylene)phenylbenzeneamine (TPBA) with hydrated Zn(ClO4 )2 under mild conditions and characterized by single-crystal X-Ray diffraction. Iodine capture studies show that the porous crystals of MOC-19 exhibit a versatile behavior to accumulate iodine species not only in vapor (for I2 ) but also in solution (for I2 and I3 (-) ), and anion-exchange experiments indicate the capacity to extract IO3 (-) anions from aqueous solution. Enrichment of iodine species from KI/I2 aqueous solution proceeds facilely, revealing a pseudo-second-order kinetics of I3 (-) adsorption. Furthermore, the electrical conductivity of MOC-19 single crystals could be significantly altered by I2 inclusion.

9.
Bioprocess Biosyst Eng ; 28(4): 211-5, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16284781

RESUMO

A novel L-ascorbyl fatty acid ester, L-ascorbyl linoleate was successfully prepared by enzymatic esterification and transesterification in a non-aqueous medium using immobilized lipase as biocatalyst. Changes in enzymatic activity and product yield were studied for the following variable: the nature of the fatty acid, the fatty acid concentration and water content. The yield of synthesis for the C18 unsaturated fatty acids were higher than for the C18 saturated fatty acid. Initial enzyme concentration does not affect the equilibrium of the reaction. And the product yield (33.5%) in the transesterification was higher than that of the esterification (21.8%) at a high-substrate concentration 0.3 M. The medium water content was found to have a distinct influence on the L-ascorbyl linoleate synthesis.


Assuntos
Ácido Ascórbico/análogos & derivados , Ácido Ascórbico/química , Ácido Linoleico/química , Ácidos Linoleicos/química , Ácidos Linoleicos/síntese química , Lipase/química , Compostos Orgânicos/química , Solventes/química , Ácido Ascórbico/síntese química , Enzimas Imobilizadas/química , Proteínas Fúngicas
10.
Biotechnol Lett ; 26(23): 1777-80, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15672213

RESUMO

L-Ascorbyl oleate and L-ascorbyl linoleate were synthesized by an immobilized lipase from Candida antarctica with yields of 38% and 44%, respectively. L-Ascorbyl oleate was stable in sterile culture medium over 12 h at 37 degrees C but L-ascorbyl linoleate degraded by 17%. Ascorbyl oleate had a better protective effect on human umbilical cord vein endothelial cells treated with H2O2 than of L-ascorbic acid-2-phosphate-6-palmitate (Asc2P6P).


Assuntos
Antioxidantes/farmacologia , Ácido Ascórbico/análogos & derivados , Ácido Ascórbico/química , Ácido Ascórbico/síntese química , Ácido Ascórbico/farmacologia , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Ácidos Linoleicos/síntese química , Ácidos Linoleicos/farmacologia , Lipase/química , Ácido Oleico/síntese química , Ácido Oleico/farmacologia , Ácidos Oleicos , Estresse Oxidativo/efeitos dos fármacos , Antioxidantes/química , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Estabilidade de Medicamentos , Células Endoteliais/metabolismo , Enzimas Imobilizadas/química , Esterificação , Proteínas Fúngicas , Humanos , Cinética , Espécies Reativas de Oxigênio/metabolismo
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