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1.
Inorg Chem ; 62(31): 12525-12533, 2023 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-37494604

RESUMEN

Switchable materials have gained significant attention due to their potential applications in data storage, sensors, and switching devices. Two-dimensional (2D) hybrid perovskites have demonstrated promising prospects for designing switchable materials, where the dynamic motion of the organic components coupled with the distortion of the inorganic framework provides the driving force for triggering multifunctional switchable properties. Herein, through the H/F substitution strategy, we report a polar 2D hybrid lead-based perovskite, (4,4-DCA)2PbBr4 (4,4-DCA = 4,4-difluorocyclohexylammonium) (1), which exhibits dual-stable behavior in a dielectric and second harmonic generation (SHG) response during the reversible phase transition process near the high Curie temperature Tc ∼ 409 K. The phase transition temperature is significantly increased by 41 K compared to the corresponding non-fluorinated (CHA)2PbBr4 (CHA = cyclohexylammonium). Remarkably, the material shows rare broad-band yellow emission under UV excitation, attributed to the induction of self-trapped exciton emission by the distortion of the [PbBr6]4- octahedra, as confirmed by the first-principles analysis. 1 also exhibited ferroelectricity with a saturation polarization value and a small coercive field. This study provides a new insight into the modification of multifunctional switchable materials through the H/F substitution strategy.

2.
Acta Pharmacol Sin ; 43(10): 2666-2677, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35228654

RESUMEN

Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer with high vascularity and frequent metastasis. Tumor-associated abnormal vasculature was reported to accelerate TNBC metastasis. Scutellarin (SC) is a natural flavonoid with a cardiovascular protective function. In this study, SC reduced TNBC metastasis and alleviated tumor-associated vascular endothelial barrier injury in vivo. SC rescued the tumor necrosis factor-α (TNFα)-induced diminishment of endothelial junctional proteins and dysfunction of the endothelial barrier in vitro. SC reduced the increased transendothelial migration of TNBC cells through a monolayer composed of TNFα-stimulated human mammary microvascular endothelial cells (HMMECs) or human umbilical vein endothelial cells (HUVECs). TNFα induced the nuclear translocation of enhancer of zeste homolog-2 (EZH2), and its chemical inhibitor GSK126 blocked TNFα-induced endothelial barrier disruption and subsequent TNBC transendothelial migration. TNF receptor 2 (TNFR2) is the main receptor by which TNFα regulates endothelial barrier breakdown. Extracellular signal-regulated protein kinase (ERK)1/2 was found to be downstream of TNFα/TNFR2 and upstream of EZH2. Additionally, SC abrogated the TNFR2-ERK1/2-EZH2 signaling axis both in vivo and in vitro. Our results suggest that SC reduced TNBC metastasis by suppressing TNFα-initiated vascular endothelial barrier breakdown through rescuing the reduced expression of junctional proteins by regulating the TNFR2-ERK1/2-EZH2 signaling pathway.


Asunto(s)
Neoplasias de la Mama Triple Negativas , Apigenina/farmacología , Línea Celular Tumoral , Glucuronatos , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Humanos , Proteínas Quinasas , Receptores Tipo II del Factor de Necrosis Tumoral , Neoplasias de la Mama Triple Negativas/patología , Factor de Necrosis Tumoral alfa/metabolismo
3.
J Asian Nat Prod Res ; 24(2): 163-169, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33844616

RESUMEN

A new amide, named rehmagluamide (1), and a new hydroxycinnamic acid derivative, named nepetoidin F (2), together with six known compounds, 2'-O-methyluridine (3), puroglutamic acid (4), biliverdic acid (5), peterolactam (6), nicotinic acid (7), nicotinamide (8), were isolated from the fresh roots of Rehmannia glutinosa. All the structures of compounds were identified by the interpretation of their spectroscopic data and comparison with those reported in the literatures. The protective effects of compounds 1-7 on normal rat kidney tubule epithelioid (NRK-52e) cells injury induced by LPS were investigated. The results indicated that compounds 1, 2, and 7 exhibited protective effects against LPS-induced NRK 52e cells injury.


Asunto(s)
Rehmannia , Amidas , Animales , Ácidos Cumáricos/farmacología , Estructura Molecular , Raíces de Plantas , Ratas
4.
Invest New Drugs ; 38(6): 1826-1835, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32535812

RESUMEN

We assessed the pharmacokinetics and safety of a single oral administration of selatinib to healthy Chinese subjects and evaluated the potential bioavailability advantage of selatinib relative to lapatinib. Healthy subjects aged 18-40 years were enrolled in this two-part study: Part 1, a single ascending dose (50-500 mg), randomized, double-blind, placebo-control study with 64 subjects; and Part 2, an open-label, positive control, randomized, three-treatment, three-period, three-sequence crossover design study, with 6 subjects administered a single 500-mg dose of selatinib tablets (A), selatinib suspension (B), or lapatinib tablets C) per cycle. In part 1, selatinib was well-tolerated up to the planned maximum dose of 500 mg; thus the maximum tolerated dose was not attained. Twenty-two adverse events were observed in 19 (36.5%) of the 52 subjects administered the test drug. The most common drug-related adverse event was diarrhea. The mean selatinib peak plasma concentration was 69.4-494 ng/mL, which was achieved in a median peak time of 3.5-4.5 h, with a mean elimination half-life between 13.8 and 15.8 h. In Part 2, A and B showed similar bioavailability. Plasma exposure to the active drug (selatinib plus the metabolite, lapatinib) after A intake was more than two-fold higher than that of the same dose of C. In the dose range of 50-500 mg, selatinib was safe and well-tolerated by healthy Chinese subjects, and it conformed with linear pharmacokinetics. Active exposure to selatinib was much greater than that to lapatinib, supporting its development as an adjuvant for anticancer treatment.


Asunto(s)
Compuestos de Anilina/administración & dosificación , Antineoplásicos/administración & dosificación , Quinazolinas/administración & dosificación , Receptor ErbB-2/antagonistas & inhibidores , Adolescente , Adulto , Compuestos de Anilina/efectos adversos , Compuestos de Anilina/sangre , Compuestos de Anilina/farmacocinética , Antineoplásicos/efectos adversos , Antineoplásicos/sangre , Antineoplásicos/farmacocinética , Disponibilidad Biológica , Estudios Cruzados , Método Doble Ciego , Receptores ErbB/antagonistas & inhibidores , Femenino , Voluntarios Sanos , Humanos , Lapatinib/metabolismo , Masculino , Quinazolinas/efectos adversos , Quinazolinas/sangre , Quinazolinas/farmacocinética , Equivalencia Terapéutica , Adulto Joven
5.
Dalton Trans ; 52(33): 11518-11525, 2023 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-37539870

RESUMEN

Organic-inorganic hybrid metal halides for high-temperature phase transition have become increasingly popular owing to their wide operating temperature range in practical applications, e.g., energy storage, permittivity switches and opto-electronic devices. This paper describes the subtle assembly of two new hybrid perovskite crystals, [Cl-C6H4-(CH2)2NH3]2CdX4 (X = Br 1; Cl 2), undergoing high-T reversible phase transformations around 335 K/356 K. Differential scanning calorimetry (DSC), differential thermal analysis (DTA) and VT PXRD tests uncover their reversible first-order phase transition behaviors. Furthermore, the compounds exhibit switchable dielectricity near T, making them potential dielectric switching materials. Hirshfeld surface analysis well discloses a distinct difference in hydrogen-bonding interaction between 1 and 2. UV spectra and computational analysis demonstrate that the compounds are a type of direct-band-gap semiconductor. This research will contribute an effective approach to the structure and development of multifunctional molecular hybrid crystals.

6.
Nat Prod Res ; 36(11): 2836-2842, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34100675

RESUMEN

A new quinic acid derivative (1) along with seven known compounds (2-8) were isolated from the fruit of Gardenia jasminoides J.Ellis. All the structures of the isolated compounds were elucidated on the basis of the analysis of multiple spectroscopic data. The α-glucosidase inhibitory effects of the isolated compounds were investigated. The results showed that compounds 1-3, 6, and 8 have moderate α-glucosidase inhibitory activities.


Asunto(s)
Gardenia , Frutas/química , Gardenia/química , Ácido Quínico/análisis , alfa-Glucosidasas
7.
Front Pharmacol ; 13: 871492, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35668951

RESUMEN

Background: The present study evaluated the safety, pharmacokinetics/pharmacodynamics (PK/PD), and absolute bioavailability (Fabs) of Dex nasal spray in healthy adult subjects, which serves as a bridge for the subsequent study in children. Methods: Part 1: a double-blind, placebo-controlled, single ascending dose study was performed on 48 subjects. For 20-/40-µg groups, every 6/2 subjects received either Dex/placebo nasal spray or Dex/placebo injection in two periods. In total, 12/4 subjects each received 100 µg Dex/placebo nasal spray. Part 2: a randomized, double-blind, placebo-controlled study; 12/4 subjects received 150 µg Dex/placebo nasal spray. Part 3: a randomized, open, self-crossover study; 12 subjects received 20 µg and 100 µg Dex nasal spray in two periods alternately. The method of administration was optimized in Part 2 and Part 3. Results: In part 1, Dex nasal spray was well tolerated up to the maximum dose of 100 µg, whereas the Fabs was tolerated to only 28.9%-32.3%. In Part 2 and Part 3, the optimized nasal spray method was adopted to promote the Fabs of Dex nasal spray to 74.1%-89.0%. A severe adverse event was found in Part 2. In Part 3 (100 µg), the Ramsay score increased the most and lasted the longest, whereas the BIS score decreased most significantly. Conclusion: Using the optimized nasal spray method, a single dose of 20/100 µg of the test drug was safe and tolerable, and 100 µg may have approached or reached the plateau of sedation. In addition, it is found that the optimized method can greatly improve the bioavailability of the test drug, leading to its higher reference value.

8.
Nat Prod Res ; 36(13): 3317-3323, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33432825

RESUMEN

A new flavonoid, saffloflavone , along with six known compounds, kaempferol-3-O-rutinoside, kaempferol-3-O-sophoroside, quercetin-3-O-ß-d-glucoside, quercetin-7-O-ß-d-glucoside, luteolin-7-O-ß-d-glucoside and kaempferol 3-O-ß-d-glucoside were isolated from the flowers of Carthamus tinctorius L. All the structures were determined by interpretation of their spectroscopic data. The cardioprotective effects of all the isolates against oxidative stress of H9c2 cells induced by H2O2 were investigated. The results showed that compounds 4-6 exhibited protective effects against of H9c2 cells injury induced by H2O2.


Asunto(s)
Carthamus tinctorius , Carthamus tinctorius/química , Flavonoides/química , Flavonoides/farmacología , Flores , Glucósidos/química , Glucósidos/farmacología , Peróxido de Hidrógeno/farmacología , Quempferoles/farmacología , Quercetina
9.
Drug Des Devel Ther ; 15: 185-193, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33469270

RESUMEN

OBJECTIVES: This study was conducted to evaluate the bioequivalence (BE) of a generic form of obeticholic acid (OCA) and OcalivaTM under fasting and fed conditions and to determine the effects of food on the pharmacokinetic (PK) profiles of OCA in healthy Chinese subjects. METHODS: A randomized, single-dose, three-sequence, three-period, partial replicated crossover study was conducted with a 21-day washout interval between periods under fasting (n=48) and fed (n=48) conditions. Blood samples for OCA and its metabolites Glyco-OCA and Tauro-OCA were collected up to 168 hours after administration in each period. PK parameters were calculated using the non-compartmental method. Geometric mean ratios for PK parameters of the test to reference drug under fasting and fed conditions and their 90% confidence intervals were estimated. Safety evaluations were carried out all through the study. RESULTS: A total of 91 subjects completed the study with 45 in a fasted state and 46 receiving a high-fat diet. There were no serious or unexpected drug-related adverse events occurring during the study. There was no significant difference in the main PK parameters of the two preparations, irrespective of the fasting or fed conditions. Under fasting and fed conditions, the SWR of lnCmax, lnAUC0-t and lnAUC0-∞ were 0.445, 0.370, 0.448, 0.340, 0.168, and 0.180, respectively. Thus, the average BE or the reference-scaled average BE was used to verify that the two preparations were bioequivalent under fasting and fed conditions. Compared with the fasting state, the AUC0-t of the test drug, the AUC0-t, and AUC0-∞ of the reference drug were higher in the fed state. CONCLUSION: The test drug and the reference drug were BE and well tolerated in Chinese healthy subjects under both fasting and fed conditions. Food-intake may cause a significant difference in the main PK parameters of the two preparations.


Asunto(s)
Ácido Quenodesoxicólico/análogos & derivados , Medicamentos Genéricos/farmacocinética , Ayuno/sangre , Adolescente , Adulto , Pueblo Asiatico , Ácido Quenodesoxicólico/sangre , Ácido Quenodesoxicólico/farmacocinética , Composición de Medicamentos , Medicamentos Genéricos/análisis , Femenino , Interacciones Alimento-Droga , Voluntarios Sanos , Humanos , Masculino , Equivalencia Terapéutica , Adulto Joven
10.
Nat Prod Res ; 35(18): 3018-3025, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31680553

RESUMEN

Two new norsesquiterpenoids, dioscopposin A (1) and dioscopposin B (2), as well as 21 known compounds (3-23) were isolated from the stems and leaves of Dioscorea oppositifolia L. Their structures were elucidated by detailed analysis of comprehensive spectroscopic data. The absolute configurations were deduced by the comparison of experimental and calculated electronic circular dichroism spectra. Estrogenic activity of all the isolated compounds were evaluated using MCF-7 cells proliferation assay and compounds 2, 3, 7, 13, 15, 16, 18 and 21 exhibited proliferation activity.


Asunto(s)
Dioscorea , Estrógenos/farmacología , Sesquiterpenos/farmacología , Dicroismo Circular , Dioscorea/química , Estrógenos/aislamiento & purificación , Humanos , Células MCF-7 , Estructura Molecular , Fitoquímicos/aislamiento & purificación , Fitoquímicos/farmacología , Hojas de la Planta/química , Tallos de la Planta/química , Sesquiterpenos/aislamiento & purificación
11.
Phytochemistry ; 190: 112893, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34332297

RESUMEN

Four previously undescribed iridoid glycosides, including two bis-iridoid glycosides, and three undescribed lignans, together with 16 known analogues, were isolated from the fruits of Gardenia jasminoides Eills. Their structures were elucidated on basis of spectroscopic methods, and the absolute configurations of three of the unknown compounds were determined by interpretation of their electronic circular dichroic (ECD) and [α] [Formula: see text] data. The α-glucosidase inhibitory effects of the isolated compounds were evaluated and all the compounds exhibited slightly inhibitory activity with the values of IC50 greater than 50 µM.


Asunto(s)
Gardenia , Lignanos , Frutas , Glicósidos/farmacología , Glicósidos Iridoides/farmacología , Lignanos/farmacología , Extractos Vegetales
12.
Int J Ophthalmol ; 13(10): 1538-1545, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33078102

RESUMEN

AIM: To investigate the alleviation of scutellarein (SN) against inner blood-retinal-barrier (iBRB) dysfunction in microglia cells stimulated by hyperglycemia and to elucidate the engaged mechanism. METHODS: Microglia BV2 cells were stimulated by using 25 mmol/L D-glucose. The same concentration of mannitol (25 mmol/L) was applied as an isotonic contrast. Real-time PCR, Western-blot assay and immunofluorescence staining assay was performed. The dysfunction of iBRB in vitro was detected by using transendothelial electrical resistance (TEER) assay. Additionally, the leakage of fluorescein isothiocyanate (FITC)-conjugated dextran (70 kDa) was detected. RESULTS: SN abrogated microglia BV2 cells activation and reduced the phosphorylated activation of extracellular signal-regulated protein kinase (ERK)1/2. SN also decreased the transcriptional activation of nuclear factor κB (NFκB) and the elevated expression of tumor necrosis factor α (TNFα), interleukin (IL)-6 and IL-1ß in BV2 cells treated with D-glucose (25 mmol/L). SN attenuated iBRB dysfunction in human retinal endothelial cells (HRECs) or choroid-retinal endothelial RF/6A cells when those cells were treated with TNFα, IL-1ß or IL-6, or co-cultured with microglia cells stimulated by D-glucose. Moreover, SN restored the decreased protein expression of tight junctions (TJs) in TNFα-treated HRECs and RF/6A cells. CONCLUSION: SN not only alleviate iBRB dysfunction via directly inhibiting retinal endothelial injury caused by TNFα, IL-1ß or IL-6, but also reduce the release of TNFα, IL-1ß and IL-6 from microglia cells by abrogating hyperglycemia-mediated the activation of microglia cells.

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