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1.
Zhongguo Zhong Yao Za Zhi ; 48(9): 2464-2470, 2023 May.
Artículo en Zh | MEDLINE | ID: mdl-37282875

RESUMEN

This paper explored the chemical constituents of Boswellia carterii by column chromatography on silica gel, Sephadex LH-20, ODS column chromatography, and semi-preparative HPLC. The structures of the compounds were identified by physicochemical properties and spectroscopic data such as infrared radiation(IR), ultra violet(UV), mass spectrometry(MS), and nuclear magnetic resonance(NMR). Seven diterpenoids were isolated and purified from n-hexane of B. carterii. The isolates were identified as(1S,3E,7E,11R,12R)-11-hydroxy-1-isopropyl-4,8,12-trimethyl-15-oxabicyclo[10.2.1]pentadeca-3,7-dien-5-one(1),(1R,3S,4R,7E,11E)-4,8,12,15,15-pentamethyl-14-oxabicyclo[11.2.1]hexadeca-7,11-dien-4-ol(2), incensole(3),(-)-(R)-nephthenol(4), euphraticanoid F(5), dilospirane B(6), and dictyotin C(7). Among them, compounds 1 and 2 were new and their absolute configurations were determined by comparison of the calculated and experimental electronic circular dichroisms(ECDs). Compounds 6 and 7 were obtained from B. carterii for the first time.


Asunto(s)
Boswellia , Diterpenos , Estructura Molecular , Boswellia/química , Diterpenos/química , Espectrometría de Masas
2.
Opt Express ; 29(5): 7654-7665, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33726262

RESUMEN

Sunlight/UV (ultraviolet)-induced degradation is still a critical issue for outdoor applications of organic light-emitting diode (OLED) displays. Therefore, effective UV-blocking structures that can prevent OLED displays from sunlight/UV degradation and still keep the OLED panels' display performance is necessary. In this report, modified distributed Bragg reflector (DBR) structures having UV-absorbing dielectric materials and adjusted layer/pair thicknesses were developed to realize effective UV blocking properties (nearly 0% transmittance below 400 nm), constantly high transmittance like glass in the visible range (∼92%) required for display applications, and sharp transition in transmission between the UV and the visible ranges. Furthermore, under the rigorous IEC 60068-2-5 solar test condition, it was verified that the developed modified, UV-blocking DBR can effectively enhance the OLED panel's resistance against UV/solar-induced degradation, effectively reducing voltage shifts of OLED devices after repeated solar test cycles.

3.
Biomed Microdevices ; 19(4): 84, 2017 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-28929244

RESUMEN

Traditional drug delivery systems, using invasive, transdermal, and oral routes, are limited by various factors, such as the digestive system environment, skin protection, and sensory nerve stimulation. To improve the drug delivery system, we fabricated a polysaccharide-based, dissolvable microneedle-based array, which combines the advantages of both invasive and transdermal delivery systems, and promises to be an innovative solution for minimally invasive drug delivery. In this study, we designed a reusable aluminum mold that greatly improved the efficiency and convenience of microneedle fabrication. Physical characterization of the polysaccharides, individual or mixed at different ratios, was performed to identify a suitable molecule to fabricate the dissolvable microneedle. We used a vacuum deposition-based micro-molding method at low temperature to fabricate the model. Using a series of checkpoints from material into product, a systematic feedback mechanism was built into the "all-in-one" fabrication step, which helped to improve production yields. The physical properties of the fabricated microneedle were assessed. The cytotoxicity analysis and animal testing of the microneedle demonstrated the safety and compatibility of the microneedle, and the successful penetration and effective release of a model protein.


Asunto(s)
Plásticos Biodegradables , Ensayo de Materiales , Agujas , Administración Cutánea , Animales , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Células 3T3 NIH
4.
Zhongguo Zhen Jiu ; 43(12): 1363-1369, 2023 Dec 12.
Artículo en Inglés, Zh | MEDLINE | ID: mdl-38092533

RESUMEN

Acupuncture-moxibustion is remarkably effective on encephalopathy, but its mechanism is unclear. With the continuous development of imaging technology, the in vivo brain imaging technology has been used increasingly in life science research and it also becomes a more effective tool for the basic research of acupuncture-moxibustion in treatment of encephalopathy. The paper summarizes the application of its technology in the basic research of acupuncture-moxibustion for encephalopathy and the characteristics of imaging, as well as the advantages and shortcomings. It is anticipated that the references may be provided for the basic research of acupuncture-moxibustion in treatment of encephalopathy and be conductive to the modernization of acupuncture-moxibustion.


Asunto(s)
Terapia por Acupuntura , Acupuntura , Encefalopatías , Moxibustión , Humanos , Encefalopatías/diagnóstico por imagen , Encefalopatías/terapia , Neuroimagen
5.
Sci Rep ; 12(1): 6628, 2022 04 22.
Artículo en Inglés | MEDLINE | ID: mdl-35459281

RESUMEN

Increasing studies have demonstrated the association between heavy metal pollution and micronutrients, especially folate. However, the relationship between cadmium and folate remains rarely discussed. In this study, we aim to explore the potential correlation between cadmium and folate in human population and highlight the possible mechanism of cadmium impacting human health. We utilized the National Health and Nutrition Examination Survey (NHANES) 2017-2018 data with 5690 participants in this study. Multivariable linear regression models were adopted to investigate the serum lead and cadmium levels and RBC folate concentration. A significant reverse relationship was found between serum lead and cadmium and RBC folate. A negative relationship between serum lead and cadmium levels and the levels of RBC folate in the U.S. adult population was found in this study. Nevertheless, due to the general limitations of the NHANES data, as a cross-sectional study, a further prospective investigation is needed to discover the causality of lead and cadmium in folate status and to determine whether the folate supplement has a beneficial influence against heavy metal toxicities.


Asunto(s)
Cadmio , Metales Pesados , Adulto , Cadmio/toxicidad , Estudios Transversales , Eritrocitos , Ácido Fólico , Humanos , Encuestas Nutricionales
6.
Chemosphere ; 278: 130334, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34126674

RESUMEN

Composite photocatalysts comprising graphitic carbon nitride (g-C3N4) and graphene materials were synthesized and evaluated in the photocatalysis of bisphenol A (BPA) with a focus on elucidating the reaction mechanism. Embedding reduced graphene oxide (rGO) to g-C3N4 significantly accelerated the photocatalysis rate of BPA by three folds under visible light irradiation at neutral pH. We showed that rGO synthesized in intimate contact with g-C3N4 increased the surface areas and electrical conductivity of the g-C3N4 composites and promoted the electron-hole pair separation. The BPA photodegradation mechanism involved selective oxidants as superoxide (O2•-) and singlet oxygen (1O2) that were formed through one-electron reduction of O2 and the unique oxidation of O2•- by photogenerated hole (h+), respectively. The synthesized photocatalyst exhibited superior visible light photoreactivity to that of N-doped P25 TiO2, good photo-stability and reuse potential, and was operative in complex wastewater. rGO embedded g-C3N4 achieved good photomineralization of BPA at 80% in 4 h compared to 40% of bare g-C3N4. This study sheds light on the photocatalysis mechanism of BPA with a metal-free, promising rGO/g-C3N4 photocatalyst.


Asunto(s)
Grafito , Compuestos de Bencidrilo , Catálisis , Compuestos de Nitrógeno , Fenoles , Oxígeno Singlete , Superóxidos
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