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1.
Curr Drug Deliv ; 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37818569

RESUMO

Immunomodulatory mechanisms are indispensable and key factors in maintaining the balance of the environment in humans. When the immune function of the immune system is impaired, autoimmune diseases occur. Excessive body fatigue, natural aging of the human body, malnutrition, genetic factors and other reasons cause low immune function, due to which the body is prone to being infected by bacteria or cancer. Clinically, the existing therapeutic drugs still have problems such as high toxicity, long treatment cycle, drug resistance and high price, so we still need to explore and develop a high efficiency and low toxicity drug. Poly(lactic-co-glycolic acid) (PLGA) refers to a non-toxic polymer compound that exhibits excellent biocompatibility. Traditional Chinese medicine (TCM) monomers come from natural plants, and have the characteristics of high efficiency and low toxicity. Applying PLGA to TCM monomers can make up for the defects of traditional dosage forms, improve bioavailability, reduce the frequency and dosage of drug use, and reduce toxicity and side effects, thus having the characteristics of sustained release and targeting. Accordingly, PLGA nanoparticles loaded with TCM monomers have been the focus of development. The previous research on drug loading advantages, preparation methods, and immune regulation of TCM PLGA nanoparticles is summarized in the following sections.

2.
J Chromatogr A ; 1496: 20-24, 2017 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-28365077

RESUMO

Breath analysis is a non-invasive approach which may be applied to disease diagnosis and pharmacokinetic study. In the case of offline analysis, the exhaled gas needs to be collected and the sampling bag is often used as the storage vessel. However, the sampling bag usually releases some extra compounds, which may interfere with the result of the breath test. In this study, a novel breath sampling glass bottle was developed with a syringe needle sampling port for solid phase microextraction (SPME). Such a glass bottle scarcely liberates compounds and can be used to collect exhaled gas for ensuing analysis by gas chromatography-mass spectrometry (GC-MS). The glass bottle sampling SPME-GC-MS analysis was carried out to investigate the breath metabolites of myrtol, a multicompound drug normally used in the treatment of bronchitis and sinusitis. Four compounds, α-pinene, 2,3-dehydro-1,8-cineole, d-limonene and 1,8-cineole were found in the exhaled breath of all eight volunteers who had taken the myrtol. While for other ten subjects who had not used the myrtol, these compounds were undetectable. In the SPME-GC-MS analysis of the headspace of myrtol, three compounds were detected including α-pinene, d-limonene and 1,8-cineole. Comparing the results of breath and headspace analysis, it indicates that 2,3-dehydro-1,8-cineole in the breath is the metabolite of 1,8-cineole. It is the first time that this metabolite was identified in human breath. The study demonstrates that the glass bottle sampling SPME-GC-MS method is applicable to exhaled gas analysis including breath metabolites investigation of drugs like myrtol.


Assuntos
Testes Respiratórios/métodos , Cromatografia Gasosa-Espectrometria de Massas , Vidro , Preparações Farmacêuticas/análise , Preparações Farmacêuticas/metabolismo , Microextração em Fase Sólida , Manejo de Espécimes/instrumentação , Adulto , Monoterpenos Bicíclicos , Cicloexanóis/análise , Cicloexanóis/metabolismo , Cicloexenos/análise , Cicloexenos/metabolismo , Combinação de Medicamentos , Eucaliptol , Feminino , Humanos , Limoneno , Masculino , Monoterpenos/administração & dosagem , Monoterpenos/análise , Monoterpenos/metabolismo , Terpenos/análise , Terpenos/metabolismo
3.
Chem Pharm Bull (Tokyo) ; 64(2): 179-88, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26833446

RESUMO

The practical syntheses of pachastrissamine (jaspine B), 2-epi-pachastrissamine, and the 2-epimer of the pyrrolidine analogue were accomplished via the stereoselective reduction of an allylketone derived from commercially available diethyl D-tartrate and the cross-metathesis of an allyltetrahydrofuran or allypyrrolidine with 1-tridecene as key steps.


Assuntos
Pirrolidinas/síntese química , Esfingosina/análogos & derivados , Conformação Molecular , Pirrolidinas/química , Esfingosina/síntese química , Esfingosina/química , Estereoisomerismo
4.
ChemSusChem ; 7(5): 1398-406, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24648252

RESUMO

Pt nanocatalysts loaded on reduced graphene oxide (Pt/RGO) were prepared by means of a convenient microwave-assisted reduction approach with ethylene glycol as reductant. The conversion of cellulose or cellobiose into sorbitol was used as an application reaction to investigate their catalytic performance. Various metal nanocatalysts loaded on RGO were compared and RGO-supported Pt exhibited the highest catalytic activity with 91.5 % of sorbitol yield from cellobiose. The catalytic performances of Pt nanocatalysts supported on different carbon materials or on silica support were also compared. The results showed that RGO was the best catalyst support, and the yield of sorbitol was as high as 91.5 % from cellobiose and 58.9 % from cellulose, respectively. The improvement of catalytic activity was attributed to the appropriate Pt particle size and hydrogen spillover effect of Pt/RGO catalyst. Interestingly, the size and dispersion of supported Pt particles could be easily regulated by convenient adjustment of the microwave heating temperature. The catalytic performance was found to initially increase and then decrease with increasing particle size. The optimum Pt particle size was 3.6 nm. These findings may offer useful guidelines for designing novel catalysts with beneficial catalytic performance for biomass conversion.


Assuntos
Biocombustíveis , Celulose/química , Grafite/química , Nanopartículas/química , Platina/química , Sorbitol/química , Catálise , Celobiose/química , Microscopia Eletrônica de Transmissão , Estrutura Molecular , Oxirredução , Óxidos , Tamanho da Partícula , Propriedades de Superfície
5.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(1): 29-32, 2012 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-22497120

RESUMO

The construction and performance study is reported for a newly developed ultraviolet photoionization ion mobility spectrometry (UV-IMS). In the present paper, an UV-IMS technique was firstly developed to detect eleven isomeric volatile organic compounds including the differences in the structure of carbon chain, the style of function group and the position of function group. Their reduced mobility values were determined and increased in this order: linears < branches < cycles, primary < secondary < tertiary, para- < meta- < ortho- and alcohols < acetones < aromas. The concentrations of analytes were obtained by means of exponential dilution method, and the experiments show that the limit of detection of the homemade UV-IMS was around ppb-ppm.


Assuntos
Espectrofotometria Ultravioleta/métodos , Compostos Orgânicos Voláteis/análise , Acetona , Álcoois
6.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(1): 46-9, 2012 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-22497124

RESUMO

In the manufacture of disposable PVC medical devices, cyclohexanone is frequently used as an adhesive reagent, which can be released into the tube airspace or stored solution and thus may cause some adverse effects on patients in therapy. In this paper, an ultraviolet photoionization ion mobility spectrometry (UV-IMS) technique has been developed to detect cyclohexanone through monitoring the gas composition within a package of infusion sets. The concentrations of cyclohexanone were prepared by means of exponential dilution method, and the experiments show that the UV-IMS has a limit of detection at 15 ppb and its measurable linear dynamics range is over three orders of magnitude. The concentrations of cyclohexanone in three brands of infusion sets packages were determined to be 16.78, 17.59 and 46.69 ppm respectively. The UV-IMS is proposed as a tool for the quality control of medical devices to monitor illegal uses of chemical solvents like cyclohexanone.


Assuntos
Cicloexanonas/análise , Equipamentos Descartáveis , Espectrofotometria Ultravioleta/métodos , Limite de Detecção , Solventes
7.
Zhonghua Yu Fang Yi Xue Za Zhi ; 39(6): 400-2, 2005 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-16329801

RESUMO

OBJECTIVE: To find out the prevalence of sleep disturbances for children aged 2 to 12 years old in Chengdu. METHODS: Totally 1 600 children aged 2-12 years old were selected from 5 districts in Chengdu and investigated by using questionnaire. RESULTS: All 1 526 survey papers were returned. The average time of every day sleep in each age group (infant group, pre-school age group and school age group) were 12.12 hours, 10.42 hours and 9.47 hours. The sleep time of the children in those three groups were much less than the standard one. The proportion of the prevalence of sleep disturbance was 37.88%. Among them, there were snoring in 5.57%, choke/gargling in 1.25%, sleep inquietude in 7.86%, mouth breathing in 4.59%, sweating in 21.36%, member spasm in 2.82%, molar teeth in 8.26%, night talking in 4.02%, somnambulate in 0.2%, bedwetting in 1.95%, and difficulty falling asleep in 10.75%. There were significant differences shown in different sexes and ages, and in incidence of symptoms of some sleep disturbances. The affecting factors were the co-sleeping, tonsillitis, bronchitis, pollen allergy and their parent's snore. CONCLUSION: The prevalence of sleep disturbances being higher and more severe than before might be due to the less sleeping time in Chengdu in children aged 2 to 12 years old. More attention should be paid by parents, the Ministry of Education and the children's doctors.


Assuntos
Transtornos do Sono-Vigília/epidemiologia , Criança , Pré-Escolar , China/epidemiologia , Feminino , Humanos , Masculino , Prevalência , Inquéritos e Questionários
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