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1.
Zhongguo Zhong Yao Za Zhi ; 46(12): 3150-3155, 2021 Jun.
Artículo en Zh | MEDLINE | ID: mdl-34467707

RESUMEN

In recent years, only a small number of new Chinese medicines have been approved for marketing, which has embodied the bottleneck in the development of the Chinese medicine industry. To tackle this problem, the National Medical Products Administration has issued a series of regulations and technical requirements. In the context of new regulations, this study deeply explored the research and development strategies of new Chinese medicines under the guidance of the new classification of drug registration, and discussed the key technical issues in the research and development.


Asunto(s)
Medicamentos Herbarios Chinos , Preparaciones Farmacéuticas , China , Medicina Tradicional China , Investigación
2.
Angew Chem Int Ed Engl ; 59(51): 23322-23328, 2020 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-32897617

RESUMEN

Porous molecular crystals sustained by hydrogen bonds and/or weaker connections are an intriguing type of adsorbents, but they rarely demonstrate efficient adsorptive separation because of poor structural robustness and tailorability. Herein, we report a porous molecular crystal based on hydrogen-bonded cyclic dinuclear AgI complex, which exhibits exceptional hydrophobicity with a water contact angle of 134°, and high chemical stability in water at pH 2-13. The seemingly rigid adsorbent shows a pore-opening or nonporous-to-porous type butane adsorption isotherm and complete exclusion of isobutane, indicating potential molecular sieving. Quantitative column breakthrough experiments show slight co-adsorption of isobutane with an experimental butane/isobutane selectivity of 23, and isobutane can be purified more efficiently than for butane. In situ powder/single-crystal X-ray diffraction and computational simulations reveal that a trivial guest-induced structural transformation plays a critical role.

3.
Angew Chem Int Ed Engl ; 58(1): 139-143, 2019 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-30320948

RESUMEN

Cobalt imidazolate frameworks are classical electrocatalysts for the oxygen evolution reaction (OER) but suffer from the relatively low activity. Here, a non-3d metal modulation strategy is presented for enhancing the OER activity of cobalt imidazolate frameworks. Two isomorphous frameworks [Co4 (MO4 )(eim)6 ] (M=Mo or W, Heim=2-ethylimidazole) having Co(eim)3 (MO4 ) units and high water stabilities were designed and synthesized. In different neutral media, the Mo-modulated framework coated on a glassy carbon electrode shows the best OER performances (1 mA cm-2 at an overpotential of 210 mV in CO2 -saturated 0.5 m KHCO3 electrolyte and 2/10/22 mA cm-2 at overpotential of 388/490/570 mV in phosphate buffer solution) among non-precious metal catalysts and even outperforms RuO2 . Spectroscopic measurements and computational simulations revealed that the non-3d metals modulate the electronic structure of Co for optimum reactant/product adsorption and tailor the energy of rate-determining step to a more moderate value.

4.
Bioorg Chem ; 81: 35-43, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30092385

RESUMEN

Four sesquiterpenoid-chalcone hybrids (nardochalaristolones A-D, 1-4), a pair of epimeric sesquiterpenoid-flavonone hybrids ((2'S)- and (2'R)-nardoflavaristolone A, 5 and 6), and a sesquiterpenoid dimer (dinardokanshone F, 7), all sharing a kanshone C-derived sesquiterpenoid unit, were isolated from the underground parts of Nardostachys jatamansi (D.Don) DC. Their structures were elucidated by analysis of the extensive spectroscopic data, and the absolute configurations were established by analysis of 2D NMR spectroscopic data including NOESY data, combined with comparisons of experimental and calculated electronic circular dichroism spectra. Further, the plausible biosynthetic pathways for these compounds were proposed. And the results of SERT activity assay revealed that nardochalaristolones C-D (3 and 4) and nardoflavaristolone A (5 and 6) significantly enhanced SERT activity, while other compounds didn't show any SERT regulatory activities.


Asunto(s)
Chalcona/aislamiento & purificación , Nardostachys/química , Sesquiterpenos/aislamiento & purificación , Chalcona/química , Estructura Molecular , Sesquiterpenos/química
5.
Planta Med ; 84(8): 536-543, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29202512

RESUMEN

Nardostachys jatamansi is a well-documented herbal agent used to treat digestive and neuropsychiatric disorders in oriental medicinal systems. However, few simple, rapid, and comprehensive methods were reported for quality assessment and control of N. jatamansi. Herein, a UPLC with photodiode array detection method was developed for both fingerprint investigation of N. jatamansi and simultaneous quantitative analysis of the six serotonin transporter modulatory constituents in N. jatamansi. For chromatographic fingerprinting, 24 common peaks were selected as characteristic peaks to assess the consistency of N. jatamansi samples from different retail sources. Six of the common peaks (5, 7, 12: , and 16:  - 18: ) were identified as desoxo-narchinol A, buddleoside, isonardosinone, nardosinone, kanshone H, and (-)-aristolone, respectively, by phytochemical investigation. Five of the six compounds significantly either enhanced or inhibited serotonin transporter activity, while (-)-aristolone (18: ) didn't show any serotonin transporter activity. In quantitative analysis, the six compounds showed good linearity (r > 0.999) within test ranges. The precision, expressed as relative standard deviation, was in the range of 0.25 - 2.77%, and the recovery of the method was in the range of 92 - 105%. The UPLC-photodiode array detection-based fingerprint analysis and quantitative methods reported here could be used for routine quality control of N. jatamansi.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Medicamentos Herbarios Chinos/química , Nardostachys/química , Control de Calidad
6.
Angew Chem Int Ed Engl ; 57(17): 4632-4636, 2018 04 16.
Artículo en Inglés | MEDLINE | ID: mdl-29457327

RESUMEN

Two-dimensional (2D) materials and ultrathin nanosheets are advantageous for elevating the catalysis performance and elucidating the catalysis mechanism of heterogeneous catalysts, but they are mostly restricted to inorganic or organic materials based on covalent bonds. We report an electrochemical/chemical exfoliation strategy for synthesizing metal-organic 2D materials based on coordination bonds. A catechol functionalized ligand is used as the redox active pillar to construct a pillared-layer framework. When the 3D pillared-layer MOF serves as an electrocatalyst for water oxidation (pH 13), the pillar ligands can be oxidized in situ and removed. The remaining ultrathin (2 nm) nanosheets of the metal-organic layers are an efficient catalyst with overpotentials as low as 211 mV at 10 mA cm-2 and a turnover frequency as high as 30 s-1 at an overpotential of 300 mV.

7.
J Am Chem Soc ; 139(15): 5285-5288, 2017 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-28376618

RESUMEN

The size-controlled synthesis of ultrasmall metal-based catalysts is of vital importance for chemical conversion technologies. Here, a cage-confinement pyrolysis strategy is presented for the synthesis of ultrasmall tungsten carbide nanoclusters/nanoparticles. An RHO type zeolitic metal azolate framework MAF-6, possessing large nanocages and small apertures, is selected to confine the metal source W(CO)6. High temperature pyrolysis gives tungsten carbide nanoclusters/nanoparticles with sizes ca. 2 nm, which can serve as an excellent electrocatalyst for the hydrogen evolution reaction. In 0.5 M H2SO4, it exhibits very low overpotential of 51 mV at 10 mA cm-2 and Tafel slope of 49 mV per decade, as well as the highest exchange current density of 2.4 mA cm-2 among all tungsten/molybdenum-based catalysts. Moreover, it also shows excellent stability and antiaggregation behavior after long-term electrolytic process.

8.
Bioorg Med Chem Lett ; 27(4): 875-879, 2017 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-28094186

RESUMEN

Nardonaphthalenones A and B (1-2), one new apo-α-carotenone (3) and four new monoterpenoids (4, 8-9 and 11), along with six known compounds (5-7, 10, 12-13) were isolated from the dried roots and rhizomes of Nardostachys chinensis Batal. Their structures were elucidated by analysis of the spectroscopic data including NMR, HRESIMS and circular dichroism data. Furthermore, the serotonin transporter (SERT)-regulating activities of these isolates were evaluated, among them compound 3 showed the strongest enhancement activity while compound 12 showed a moderate inhibition activity on SERT.


Asunto(s)
Monoterpenos/química , Naftalenos/química , Nardostachys/química , Expresión Génica/efectos de los fármacos , Células HEK293 , Humanos , Espectroscopía de Resonancia Magnética , Conformación Molecular , Monoterpenos/aislamiento & purificación , Monoterpenos/farmacología , Naftalenos/aislamiento & purificación , Naftalenos/farmacología , Nardostachys/metabolismo , Raíces de Plantas/química , Raíces de Plantas/metabolismo , Rizoma/química , Rizoma/metabolismo , Proteínas de Transporte de Serotonina en la Membrana Plasmática/química , Proteínas de Transporte de Serotonina en la Membrana Plasmática/genética , Proteínas de Transporte de Serotonina en la Membrana Plasmática/metabolismo
9.
Chem Biodivers ; 14(5)2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28130824

RESUMEN

Four new iridoids, 2'-O-(E)-coumaroylshanzhiside (1), 6'-O-(E)-coumaroylshanzhiside (2), 8α-butylgardenoside B (3), 6α-methoxygenipin (4), and one new phenylpropanoid glucoside, 5-(3-hydroxypropyl)-2-methoxyphenyl ß-d-glucopyranoside (5), together with sixteen known compounds, were isolated from the edible flowers of wild Gardenia jasminoides J.Ellis. Their chemical structures were characterized by extensive spectroscopic techniques, including 1D- and 2D-NMR, HR-ESI-MS, and CD experiments. The absolute configurations of the new isolates' sugar moiety were assigned by HPLC analysis of the acid hydrolysates. Furthermore, the antioxidant activities of those isolates were preliminarily evaluated by DPPH scavenging experiment. And comparison of 1 H-NMR spectra for the EtOH extract of G. jasminoides J.Ellis, gardenoside B and geniposide revealed that the flowers of this plant have a considerable content of gardenoside B instead of geniposide in the fruits, indicating different activities and applications in people's daily life.


Asunto(s)
Gardenia/química , Extractos Vegetales/análisis , Antioxidantes/aislamiento & purificación , Antioxidantes/farmacología , Flores/química , Frutas/química , Iridoides/aislamiento & purificación , Estructura Molecular , Extractos Vegetales/química , Análisis Espectral
10.
Zhongguo Zhong Yao Za Zhi ; 42(10): 2006-2016, 2017 May.
Artículo en Zh | MEDLINE | ID: mdl-29090565

RESUMEN

The existing antidepressants demonstrated delayed onset of clinical effects, so fast-onset antidepressants are required. Essential oil of herbs showed potentials fast-onset antidepressant potential. First, its aromatic odor can directly activate olfactory nerves; its high lipophilicity causes a high blood-brain barrier penetration rate; and its high volatility is suitable for nasal-brain targeting and inhalation delivery. Therefore, essential oils can rapidly regulate brain functions by multiple ways, suggesting a fast-onset antidepressant potential. Second, the advance of studies on chemistry and pharmacology of antidepressant essential oils demonstrated chemical substances, antidepressant effects and possible action mechanisms of antidepressant essential oils. Third, the effect of essential oils' antidepressant components on fast-onset antidepressant targets was investigated. It was found that chemical constituents of essential oils antagonized NMDA receptor activities, suggesting that essential oils have fast-onset antidepressant effect. Finally, characteristics of essential oils, fast-onset antidepressant targets and drug delivery methods are integrated to give full play to essential oils' fast-onset antidepressant advantage and provide a new direction for new drug discovery.


Asunto(s)
Antidepresivos/farmacología , Aceites Volátiles/farmacología , Aceites de Plantas/farmacología , Administración por Inhalación , Encéfalo/efectos de los fármacos , Humanos
11.
J Asian Nat Prod Res ; 18(7): 697-704, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26841079

RESUMEN

A new saponin, isonarthogenin 3-O-ß-d-glucopyranosyl-(1→4)-ß-d-galactopyranoside (1), together with twelve known compounds, were isolated from the rhizomes of Polygonatum sibiricum. The structures of these compounds were elucidated by analysis of their 1D/2D NMR and MS data. Among them, phenol compounds 4-7 and 9-10 showed significant inhibitions against the formation of advanced glycosylation end products, with IC50 values of 0.091 ± 0.0021, 0.10 ± 0.041, 0.014 ± 0.0027, 0.11 ± 0.011, 0.13 ± 0.045, and 0.055 ± 0.019 µM, respectively. The results will promote exploiting potential medicinal use of these compounds in the prevention of diabetic complications and supporting Polygonatum sibiricum as a functional food for healthy and medicinal diet.


Asunto(s)
Productos Finales de Glicación Avanzada/antagonistas & inhibidores , Polygonatum/química , Saponinas/aislamiento & purificación , Saponinas/farmacología , Medicamentos Herbarios Chinos/química , Humanos , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Rizoma/química , Saponinas/química
12.
Yao Xue Xue Bao ; 51(1): 100-4, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27405169

RESUMEN

A new caffeate compound, (E)-erythro-syringylglyceryl caffeate (1), was isolated from the roots and rhizomes of Nardostachys chinensis Batal., together with nine known phenolic compounds, including (+)-licarin A (2), naringenin 4', 7-dimethyl ether (3), pinoresinol-4-O-ß-D-glucoside (4), caraphenol A (5), Z-miyabenol C (6), protocatechuic acid (7), caffeic acid (8), gallic acid (9) and vanillic acid (10). Their chemical structures were elucidated on the basis of spectroscopic data and physicochemical properties. Furthermore, this is the first report of compounds 2, 5 and 6 from Nardostachys genus.


Asunto(s)
Ácidos Cafeicos/aislamiento & purificación , Nardostachys/química , Ácidos Cafeicos/química , Flavanonas/química , Flavanonas/aislamiento & purificación , Furanos/química , Furanos/aislamiento & purificación , Glucósidos/química , Glucósidos/aislamiento & purificación , Hidroxibenzoatos/química , Hidroxibenzoatos/aislamiento & purificación , Lignanos/química , Lignanos/aislamiento & purificación , Raíces de Plantas/química , Rizoma/química , Ácido Vanílico/química , Ácido Vanílico/aislamiento & purificación
13.
Zhongguo Zhong Yao Za Zhi ; 41(6): 1144-1151, 2016 Mar.
Artículo en Zh | MEDLINE | ID: mdl-28875685

RESUMEN

There have been many reports about the anti-aging effect of traditional Chinese medicine (TCM), but the material basis and mechanism of action have not been clearly elucidated. AMP-activated protein kinase (AMPK) is the receptor of energy metabolism and its life extending effect has been confirmed in different experiments. Over expression or activation with metform in of AAK-2/AMPK has been shown to extend life expectancy in nematodes and Drosophila. The possible downstream pathways of AMPK against aging include TOR/S6k pathway, FOXOs pathway and CRTC pathway. One of the core concepts of traditional Chinese medicine is disease prevention, for which one of manifestations is to improve the body with the same source of medicine and food to achieve longevity. It is possible to activate AMPK to achieve the goal of health preservation and prolonging the life by some of the "medicine-food harmony" treatments. Our survey finds that in "medicine-food harmony" compound TCM, "invigorating the kidney deficiency and promoting blood circulation" class dominates and Salviae Miltiorrhizae Radix Rhizoma, Astragali Radix, Coptidis Rhizoma, Poria, Atractylodes Macrocephalae Rhizoma, Radix et Rhizoma Rhei, and Ginseng Radix et Rhizoma are used in high frequency. Network pharmacology analysis using ingenuity pathway analysis (IPA) software revealed that TCM-derived drugs interacting with AMPK target proteins included berberine, emodin, curcumin, resveratrol, alcohol, cordyceps, arctiin, suggesting in a certain extent the feasibility of "medicine -food homology" drugs to extend the lifespan through the AMPK pathway. Our study combines a comprehensive database query and an IPA network pharmacology analysis to identify Chinese medicine monomer and components that may activate AMPK pathway to delay aging and to discuss the potential of these medicine by improving energy metabolism to delay the aging process, based on the concept of traditional Chinese medicine "medicine-food homology".


Asunto(s)
Envejecimiento/efectos de los fármacos , Envejecimiento/metabolismo , Medicamentos Herbarios Chinos/uso terapéutico , Proteínas Quinasas/metabolismo , Quinasas de la Proteína-Quinasa Activada por el AMP , Restricción Calórica , Metabolismo Energético/efectos de los fármacos , Humanos , Medicina Tradicional China , Fitoterapia , Proteínas Quinasas/genética , Transducción de Señal/efectos de los fármacos
14.
Zhongguo Zhong Yao Za Zhi ; 41(10): 1903-1909, 2016 May.
Artículo en Zh | MEDLINE | ID: mdl-28895341

RESUMEN

Anaphylactoid reaction (AR) is the most common adverse reaction of injection formulations, however, there are obvious drawbacks in available methods for AR detection. A novel in vitro detection method for AR was established based on fluorescent labeling and high content screen (HCS) system in present study. With the use of RBL-2H3 cells degranulation model, positive cell count was determined with specific cellular membrane fluorescent dye FM4-64 labeling vesicle recycle, and total cells count was determined with specific nucleus fluorescent dye Hochest 3334, and then the ratio of cells degranulation after drug stimulation was calculated. In order to verify the reliability of this HCS method, positive drug Compound 48/80 was first used to confirm the consistence of HCS method with the traditional ß-hexosaminidase release test and the Evans blue staining ears test in mice. The results showed high consistence between HCS method and traditional testing methods, and the HCS method showed higher sensitivity than the other two tests. Then 30 samples of Danhong injection (DHI) with clinical allergy symptoms further were used to confirm the reliability of this HCS method. The HCS results showed high consistence with the clinical report, and the HCS method had the advantage in reducing the interference by drug color. Therefore, this HCS method is reliable, sensitive, simple and high-throughput method in detection of AR, applicable for the AR evaluation of injection formulations, and can provide guidance for safety of clinical application in clinical practice.


Asunto(s)
Anafilaxia/inducido químicamente , Degranulación de la Célula/efectos de los fármacos , Pruebas de Toxicidad , Animales , Línea Celular , Medicamentos Herbarios Chinos/toxicidad , Ratones , Compuestos de Piridinio , Compuestos de Amonio Cuaternario , Reproducibilidad de los Resultados , beta-N-Acetilhexosaminidasas , p-Metoxi-N-metilfenetilamina/toxicidad
15.
Angew Chem Int Ed Engl ; 55(52): 16021-16025, 2016 12 23.
Artículo en Inglés | MEDLINE | ID: mdl-27891722

RESUMEN

Mixing molecular building blocks in the solid solution manner is a valuable strategy to obtain structures and properties in between the isostructural parent metal-organic frameworks (MOFs). We report nonlinear/synergistic solid-solution effects using highly related yet non-isostructural, phosphorescent CuI triazolate frameworks as parent phases. Near the phase boundaries associated with conformational diversity and ligand heterogeneity, the porosity (+150 %) and optical O2 sensitivity (410 times, limit of detection 0.07 ppm) can be drastically improved from the best-performing parent MOFs and even exceeds the records hold by precious-metal complexes (3 ppm) and C70 (0.2 ppm).

16.
Bioorg Med Chem Lett ; 25(19): 4214-8, 2015 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-26296476

RESUMEN

A novel sesquiterpene with an unprecedented epoxy lactone skeleton, named tatarinolactone, together with two new amides, a new biphenylpropanoid and two known lignans were isolated from the rhizomes of Acorus tatarinowii Schott. Their structures were identified as 6,7,8-trihydroxy-4α-isobutyl-4,7-dimethylhexahydro-6,8α-epoxychromen-2(3H)-one (1), (E)-methyl 4-[3-(4-hydroxy-3-methoxyphenyl)acrylamido]butanoate (2), (Z)-methyl 4-[3-(4-hydroxy-3-methoxyphenyl)acrylamido]butanoate enol isomer (3), (R)-4-hydroxy-3-[1-hydroxy-3-(4-hydroxy-3-methoxyphenyl)propan-2-yl]-5-methoxybenzoic acid (4), (2S,3R)-ceplignan (5), and (2R,3S)-ceplignan (6), respectively, based on extensive spectroscopic analysis and by comparison to the known compounds. To test their effects on serotonin transporters, a high content assay using hSERT-HEK293 cell line was adopted. Results indicated that compounds 1 and 4 significantly inhibited SERT activity, while compounds 2, 3, 5, and 6 significantly enhanced SERT activity, which partly explain the traditional uses of the rhizomes of Acorus tatarinowii Schott in treatments of neuropsychiatric and digestive disorders.


Asunto(s)
Acorus/química , Fenoles/farmacología , Rizoma/química , Proteínas de Transporte de Serotonina en la Membrana Plasmática/metabolismo , Sesquiterpenos/farmacología , Relación Dosis-Respuesta a Droga , Células HEK293 , Humanos , Estructura Molecular , Fenoles/química , Fenoles/aislamiento & purificación , Sesquiterpenos/química , Sesquiterpenos/aislamiento & purificación , Relación Estructura-Actividad
17.
Neuro Endocrinol Lett ; 34(2): 143-53, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23645312

RESUMEN

BACKGROUND: Photoperiodic changes mediate certain physiological or pathological alterations in organisms. Solstices represent either the longest or shortest photoperiod of a year. OBJECTIVES: Intact and pinealectomized rats were used to investigate the potential changes of reproductive hormones in the hypothalamus-pituitary-testis (HPT) axis including GnRH, FSH, LH, testosterone and melatonin, and their receptors at summer solstice (SS) and winter solstices (WS). METHODS: The levels of reproductive hormones in HPT axis and the binding characteristics of their receptors were examined using radioimmunoassay and radioreceptor assay techniques, respectively. RESULTS: The results indicate that in the intact male rat, GnRH, LH and testosterone are higher at the SS than at the WS. However, FSH exhibited no significant seasonal changes. In the testis, Bmax and Kd of LH receptors are higher at the WS than at the SS while those of FSH receptors are higher at the SS than at the WS. In addition, the melatonin in HPT axis appeared significant differences between WS and SS. Bmax and Kd of melatonin receptors in the hypothalamus and pituitary also showed higher at the WS than at the SS. Moreover, reproductive hormone production lost their seasonal rhythms after pinealectomy. CONCLUSION: The most important discovery in this study is that we first reported that pinealectomy had profound effects on the binding characteristics of melatonin with its subtype receptors. Especially at the hypothalamus, the dominated melatonin receptors shifted from MT1 to MT2 after pinealectomy at the two solstices.


Asunto(s)
Glándula Pineal/metabolismo , Glándula Pineal/cirugía , Estaciones del Año , Testículo/metabolismo , Testosterona/metabolismo , Animales , Ritmo Circadiano/fisiología , Masculino , Fotoperiodo , Hipófisis/metabolismo , Ratas , Ratas Sprague-Dawley
18.
ChemSusChem ; 15(6): e202102450, 2022 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-34978758

RESUMEN

The electrocatalytic nitrate-to-ammonia reduction reaction route (NARR) is one of the emerging routes toward green ammonia synthesis, and its conversion efficiency is controlled mainly by the hydrogenation selectivity. This study proposed a likely NARR route feasible and effective even in a neutral condition. Its high catalytic selectivity and efficiency were achieved by a switch of the sulfate solution to the phosphate buffer solution (PBS), while conditions of NO3 - concentration, pH, and applied potential were maintained unchanged. Specifically, the faradaic efficiencies toward NH3 (FE NH 3 ) in Na2 SO4 were as low as 9.8, 19.8, and 11.4 % versus remarkably jumping to 82.8, 90.5, and 89.5 % in PBS under -0.75, -1.0, and -1.25 V, respectively. The corresponding faradaic efficiencies toward NO2 - (FE NO 2 - ), 77.0, 69.2, and 73.7 % in Na2 SO4 , significantly dropped to10.8, 7.4, and 4.4 % in PBS, evidencing an unexpected selectivity reversal of the nitrate reduction from NO2 - to NH3 . This insight was further revealed by the visualization of the pH gradient near the electrode surface during NARR and confirmed by density functional theory calculations; PBS notably facilitated the proton transport and active mitigation over the proton transfer barrier. The use of PBS resulted in a maximal partial current density toward NH3 (J NH 3 ) and NH3 formation rate (r NH 3 ) up to 133.5 mA cm-2 and 1.74×10-7  mol s-1 cm-2 in 1.0 m KNO3 at -1.25 V.

19.
Front Pharmacol ; 12: 790072, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35002723

RESUMEN

Background: Acute lung injury (ALI) is characterized by dysfunction of the alveolar epithelial membrane caused by acute inflammation and tissue injury. Qingwenzhike (QWZK) prescription has been demonstrated to be effective against respiratory viral infections in clinical practices, including coronavirus disease 2019 (COVID-19) infection. So far, the chemical compositions, protective effects on ALI, and possible anti-inflammatory mechanisms remain unknown. Methods: In this study, the compositions of QWZK were determined via the linear ion trap/electrostatic field orbital trap tandem high-resolution mass spectrometry (UHPLC-LTQ-Orbitrap MS). To test the protective effects of QWZK on ALI, an ALI model induced by lipopolysaccharide (LPS) in rats was used. The effects of QWZK on the LPS-induced ALI were evaluated by pathological changes and the number and classification of white blood cell (WBC) in bronchoalveolar lavage fluid (BALF). To investigate the possible underlying mechanisms, the contents of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), monocyte chemoattractant protein (MCP-1), interleukin-1ß (IL-1ß), interleukin-18 (IL-18), and immunoregulatory-related factors interferon-γ (IFN-γ) were detected by ELISA. Furthermore, the expression of Toll-like receptor 4 (TLR4), p-IKKα/ß, IKKα, IKKß, p-IκBα, IκBα, p-NF-κB, nuclear factor-κB (NF-κB), NOD-like receptor family pyrin domain containing 3 (NLRP3), cleaved caspase-1, pro-caspase-1, apoptosis-associated speck-like protein containing CARD (ASC), and ß-actin were tested by Western blot. Results: A total of 99 compounds were identified in QWZK, including 33 flavonoids, 23 phenolic acids, 3 alkaloids, 3 coumarins, 20 triterpenoids, 5 anthraquinones, and 12 others. ALI rats induced by LPS exhibited significant increase in neutrophile, significant decrease in lymphocyte, and evidently thicker alveolar wall than control animals. QWZK reversed the changes in WBC count and alveolar wall to normal level on the model of ALI induced by LPS. ELISA results revealed that QWZK significantly reduced the overexpression of proinflammatory factors IL-6, TNF-α, MCP-1, IL-1ß, IL-18, and IFN-γ induced by LPS. Western blot results demonstrated that QWZK significantly downregulated the overexpression of TLR4, p-IKKα/ß, p-IκBα, p-NF-κB, NLRP3, cleaved caspase-1, and ASC induced by LPS, which suggested that QWZK inhibited TLR4/NF-κB signaling pathway and NLRP3 inflammasomes. Conclusions: The chemical compositions of QWZK were first identified. It was demonstrated that QWZK showed protective effects on ALI induced by LPS. The possible underlying mechanisms of QWZK on ALI induced by LPS was via inhibiting TLR4/NF-kB signaling pathway and NLRP3 inflammasome activation. This work suggested that QWZK is a potential therapeutic candidate for the treatments of ALI and pulmonary inflammation.

20.
Adv Mater ; 33(22): e2007368, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33893666

RESUMEN

Behaving as structural protectors and electronic modulators, catalyst supports such as graphene derivatives are generally constructed by covalent bonds. Here, hydrogen-bonded ultrathin nanosheets are reported as a new type of catalyst support. Melamine (M) and cyanuric acid (CA) molecules self-assemble to form the graphite-like hydrogen-bonded co-crystal M-CA, which can be easily exfoliated by ultrasonic treatment to yield ultrathin nanosheets with thickness of ≈1.6 nm and high stability at pH = 0. The dynamic nanosheets form adaptive defects/pores in the synthetic process of CoP nanoparticles, giving embedded composite with high hydrogen evolution activity (overpotential of 66 mV at 10 mA cm-2 ) and stability. Computational calculations, X-ray photoelectron spectroscopy, and X-ray absorption spectroscopy unveil the electron modulation effects of the nanosheets. This pseudo-porous catalyst support also can be applied to other metal phosphides.

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