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1.
Small ; : e2310340, 2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38456789

RESUMEN

Chondrosarcoma(CS), a prevalent primary malignant bone tumor, frequently exhibits chemotherapy resistance attributed to upregulated anti-apoptosis pathways such as the Bcl-2 family. In this manuscript, a new strategy is presented to augment chemosensitivity and mitigate systemic toxicity by harnessing a nano-enabled drug delivery hydrogel platform. The platform utilizes "PLGA-PEG-PLGA", an amphiphilic triblock copolymer combining hydrophilic polyethylene glycol (PEG) and hydrophobic polylactide glycolide (PLGA) blocks, renowned for its properties conducive to crafting a biodegradable, temperature-sensitive hydrogel. This platform is tailored to encapsulate a ratiometrically designed dual-loaded liposomes containing a first-line chemo option for CS, Doxorubicin (Dox), plus a calculated amount of small molecule inhibitor for anti-apoptotic Bcl-2 pathway, ABT-737. In vitro and in vivo evaluations demonstrate successful Bcl-2 suppression, resulting in the restoration of Dox sensitivity, evident through impeded tumor growth and amplified necrosis rates at the tumor site. This delivery system showcases remarkable thermal responsiveness, injectability, and biodegradability, all finely aligned with the clinical demands of CS treatment. Collectively, this study introduces a transformative avenue for tackling drug resistance in CS chemotherapy, offering significant clinical potential.

2.
Environ Sci Technol ; 58(26): 11812-11821, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38897924

RESUMEN

We developed a simple strategy for preparing IrSn bimetallic clusters encapsulated in pure silicon zeolites via a one-pot hydrothermal synthesis by using diethylamine as a stabilizing agent. A series of investigations verified that metal species have been confined successfully in the inner of MFI zeolites. IrSn bimetallic cluster catalysts were efficient for the CO selective catalytic reduction of NOx in the presence of excess O2. Furthermore, the 13CO temperature-programmed surface reaction results demonstrated that NO2 and N2O could form when most of the CO was transformed into CO2 and that Sn modification could passivate CO oxidation on the IrSn bimetallic clusters, leading to more reductants that could be used for NOx reduction at high temperatures. Furthermore, SO2 can also influence the NOx conversion by inhibiting the oxidation of CO. This study provides a new strategy for preparing efficient environmental catalysts with a high dispersion of metal species.


Asunto(s)
Oxidación-Reducción , Oxígeno , Zeolitas , Zeolitas/química , Catálisis , Oxígeno/química , Monóxido de Carbono/química , Estaño/química , Óxidos de Nitrógeno/química
3.
Environ Sci Technol ; 58(20): 8976-8987, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38653761

RESUMEN

Nitrous oxide (N2O) is a potent greenhouse gas with a high global warming potential, emphasizing the critical need to develop efficient elimination methods. Electrocatalytic N2O reduction reaction (N2ORR) stands out as a promising approach, offering room temperature conversion of N2O to N2 without the production of NOx byproducts. In this study, we present the synthesis of a copper-based single-atom catalyst featuring atomic Cu on nitrogen-doped carbon black (Cu1-NCB). Attributed to the highly dispersed single-atom Cu sites and the effective suppression of the hydrogen evolution reaction, Cu1-NCB demonstrated an optimal N2 faradaic efficiency (82.1%) and yield rate (3.53 mmol h-1 mgmetal-1) at -0.2 and -0.5 V vs RHE, respectively, outperforming previously reported N2ORR electrocatalysts. Further, a gas diffusion electrode cell was employed to improve mass transfer and achieved a 28.6% conversion rate of 30% N2O with only a 14 s residence time, demonstrating the potential for practical application. Density functional theory calculations identified Cu-N4 as the crucial active site for N2ORR, highlighting the significance of the unsaturated coordination and metal-support electronic structure. O-terminal adsorption of N2O was favored, and the dissociative adsorption (*ON2 → *O + N2) was the rate-determining step. These findings reveal the broad prospects of N2O decomposition via electrocatalysis.


Asunto(s)
Carbono , Cobre , Nitrógeno , Óxido Nitroso , Nitrógeno/química , Catálisis , Óxido Nitroso/química , Carbono/química , Cobre/química , Oxidación-Reducción
4.
J Nat Prod ; 87(4): 1036-1043, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38600636

RESUMEN

Triterpenoids are a type of specialized metabolites that exhibit a wide range of biological activities. However, the availability of some minor triterpenoids in nature is limited, which has hindered our understanding of their pharmacological potential. To overcome this limitation, heterologous biosynthesis of triterpenoids in yeast has emerged as a promising and time-efficient production platform for obtaining these minor compounds. In this study, we analyzed the transcriptomic data of Enkianthus chinensis to identify one oxidosqualene cyclase (EcOSC) gene and four CYP716s. Through heterologous expression of these genes in yeast, nine natural pentacyclic triterpenoids, including three skeleton products (1-3) produced by one multifunctional OSC and six minor oxidation products (4-9) catalyzed by CYP716s, were obtained. Of note, we discovered that CYP716E60 could oxidize ursane-type and oleanane-type triterpenoids to produce 6ß-OH derivatives, marking the first confirmed C-6ß hydroxylation in an ursuane-type triterpenoid. Compound 9 showed moderate inhibitory activity against NO production and dose-dependently reduced IL-1ß and IL-6 production at the transcriptional and protein levels. Compounds 1, 2, 8, and 9 exhibited moderate hepatoprotective activity with the survival rates of HepG2 cells from 61% to 68% at 10 µM.


Asunto(s)
Antiinflamatorios , Sistema Enzimático del Citocromo P-450 , Transferasas Intramoleculares , Triterpenos , Triterpenos/farmacología , Triterpenos/química , Humanos , Sistema Enzimático del Citocromo P-450/metabolismo , Antiinflamatorios/farmacología , Antiinflamatorios/química , Estructura Molecular , Saccharomyces cerevisiae , Hidroxilación , Células Hep G2 , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Sustancias Protectoras/farmacología , Sustancias Protectoras/química
5.
Environ Toxicol ; 39(5): 2855-2868, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38293814

RESUMEN

Numerous studies have elucidated the intricate relationship between bronchial asthma and small cell lung cancer (SCLC), as well as the role lipid metabolism genes play in transitioning from bronchial asthma to SCLC. Despite this, the predictive power of single gene biomarkers remains insufficient and necessitates the development of more accurate prognostic models. In our study, we downloaded and preprocessed scRNA-seq of SCLC from the GEO database GSE164404 and severe asthma scRNA-seq from GSE145013 using the Seurat package. Using the MSigDB database and geneCard database, we selected lipid metabolism-related genes and performed scRNA-seq data analysis from the gene expression GEO database, aiming to uncover potential links between immune signaling pathways in bronchial asthma and SCLC. Our investigations yielded differentially expressed genes based on the scRNA-seq dataset related to lipid metabolism. We executed differential gene analysis, gene ontology, and Kyoto Encyclopedia of Genes and Genomes analyses. In-depth GSEA pathway activation analysis, crucial target gene predictions via protein-protein interactions, and key cluster gene evaluations for differential and diagnostic ROC values correlation analysis confirmed that key cluster genes are significant predictors for the progression of bronchial asthma to SCLC. To validate our findings, we performed wet laboratory experiments using real-time quantitative PCR to assess the expression of these relevant genes in SCLC cell lines. In conclusion, this research proposes a novel lipid metabolism-related gene marker that can offer comprehensive insights into the pathogenesis of bronchial asthma leading to SCLC. Although this study does not directly focus on senescence-associated molecular alterations, our findings in the lipid metabolism genes associated with inflammation and cancer progression offer valuable insights for further research targeting senescence-related changes in treating inflammatory diseases.


Asunto(s)
Asma , Neoplasias Pulmonares , Carcinoma Pulmonar de Células Pequeñas , Humanos , Carcinoma Pulmonar de Células Pequeñas/genética , Metabolismo de los Lípidos/genética , Biomarcadores de Tumor/genética , Neoplasias Pulmonares/genética , Asma/genética
6.
J Asian Nat Prod Res ; 26(4): 452-464, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37655543

RESUMEN

Six previously undescribed prenylated C6-C3 derivatives (1-6) were isolated from the root of Illicium ternstroemioides A. C. Smith. Their structures were elucidated based on extensive spectroscopic analyses (UV, IR, 1D and 2D NMR, and HRESIMS). The absolute configurations of 1-3 were determined using electronic circular dichroism (ECD), and Mo2(OAc)4 induced circular dichroism (ICD). Compound 3 exhibited weak activity against Coxsackievirus B3 with an IC50 value of 33.3 µM, and compound 5 exhibited more potent activity against Coxsackievirus B3 with an IC50 value of 6.4 µM.


Asunto(s)
Illicium , Illicium/química , Estructura Molecular , Espectroscopía de Resonancia Magnética , Dicroismo Circular , Antivirales/farmacología
7.
J Asian Nat Prod Res ; 26(2): 204-213, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38213077

RESUMEN

Three new cadinane sesquiterpenes (1-3) and three known sesquiterpenes were isolated from the stems and branches of Illicium ternstroemioides A. C. Smith. The structures of the new compounds were elucidated by extensive analysis of spectroscopic and HRESIMS data. The structures of illiternins A-C (1-3) were confirmed by single crystal X-ray diffraction, allowing for the determination of their absolute configurations. Compounds 3 and 6 exhibited antiviral activity against Coxsackievirus B3 with IC50 values of 33.3 and 57.7 µM, respectively.


Asunto(s)
Illicium , Sesquiterpenos , Illicium/química , Estructura Molecular , Sesquiterpenos Policíclicos , Sesquiterpenos/química
8.
Angew Chem Int Ed Engl ; 63(13): e202315674, 2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38327006

RESUMEN

Sesquiterpene synthases (STPSs) catalyze carbocation-driven cyclization reactions that can generate structurally diverse hydrocarbons. The deprotonation-reprotonation process is widely used in STPSs to promote structural diversity, largely attributable to the distinct regio/stereoselective reprotonations. However, the molecular basis for reprotonation regioselectivity remains largely understudied. Herein, we analyzed two highly paralogous STPSs, Artabotrys hexapetalus (-)-cyperene synthase (AhCS) and ishwarane synthase (AhIS), which catalyze reactions that are distinct from the regioselective protonation of germacrene A (GA), resulting in distinct skeletons of 5/5/6 tricyclic (-)-cyperene and 6/6/5/3 tetracyclic ishwarane, respectively. Isotopic labeling experiments demonstrated that these protonations occur at C3 and C6 of GA in AhCS and AhIS, respectively. The cryo-electron microscopy-derived AhCS complex structure provided the structural basis for identifying different key active site residues that may govern their functional disparity. The structure-guided mutagenesis of these residues resulted in successful functional interconversion between AhCS and AhIS, thus targeting the three active site residues [L311-S419-C458]/[M311-V419-A458] that may act as a C3/C6 reprotonation switch for GA. These findings facilitate the rational design or directed evolution of STPSs with structurally diverse skeletons.


Asunto(s)
Transferasas Alquil y Aril , Sesquiterpenos , Microscopía por Crioelectrón , Sesquiterpenos/química , Catálisis , Dominio Catalítico , Transferasas Alquil y Aril/genética
9.
J Surg Res ; 285: 107-113, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36652769

RESUMEN

INTRODUCTION: This study aims to retrospectively compare the efficacy and safety of subxiphoid and subcostal arch thoracoscopic resection (SR) and the median sternotomy (MS) for thymoma with myasthenia gravis (MG) via propensity-matched analysis. METHODS: We retrospectively analyzed 502 patients with thymoma and MG in Tangdu Hospital of the Fourth Military Medical University from December 2012 to December 2017. The patients were allocated to SR group (n = 424) and MS group (n = 78). Perioperative outcomes were compared between SR group and MS group by using propensity-matched analysis. RESULTS: All SR and MS operations were accomplished successfully. Most postoperative outcomes between the two groups showed no significant difference such as remission of MG and postoperative complication (P > 0.05). There were statistically significant differences between MS group and SR group in operation time [(116.3 ± 33.7) min versus (52.2 ± 31.3) min], intraoperative blood loss [(145.2 ± 26.7) mL versus (51.2 ± 10.3) mL], chest drainage duration (3.4 d versus 0 d), days of hospital-stay (5.2 d versus 2.7 d), patient satisfaction score (5.9 ± 2.3 versus 8.7 ± 1.2), the incidence of complications and pain scores, with all P values < 0.05. CONCLUSIONS: This study suggests that subxiphoid and subcostal arch thoracoscopic resection is a less invasive procedure with good safety and feasibility as compared with median sternotomy for thymoma with myasthenia gravis.


Asunto(s)
Miastenia Gravis , Timoma , Neoplasias del Timo , Humanos , Pueblos del Este de Asia , Miastenia Gravis/cirugía , Estudios Retrospectivos , Esternotomía , Cirugía Torácica Asistida por Video , Timectomía , Timoma/complicaciones , Timoma/cirugía , Neoplasias del Timo/complicaciones , Neoplasias del Timo/cirugía , Resultado del Tratamiento
10.
Environ Sci Technol ; 57(24): 9105-9114, 2023 06 20.
Artículo en Inglés | MEDLINE | ID: mdl-37285468

RESUMEN

The development of efficient catalysts for the selective catalytic reduction of NO by CO (CO-SCR) in the presence of O2 is highly desirable for controlling the emission of toxic gases from tailpipes. Here, a bimetallic IrRu/ZSM-5 catalyst was prepared for the selective catalytic reduction of NO by CO in the presence of O2 (5%) for the low-temperature treatment of exhaust gas. IrRu/ZSM-5 afforded 90% NOx conversion in the range of 225-250 °C and maintained 90% NOx conversion after 12 h of reaction. Ru addition inhibited agglomeration of the Ir particles during the reduction process and provided more active sites for NO adsorption. Isotopic C13O tracing and in situ diffuse reflectance infrared Fourier-transform spectroscopy experiments were used to elucidate the CO-SCR mechanism in the absence or presence of O2. NCO could easily form on the surface of catalysts in the absence of O2, whereas NCO formation has been inhibited owing to the quick consumption of CO in the presence of O2. Moreover, some byproducts such as N2O and NO2 are generated in the presence of O2. Finally, a possible mechanism for CO-SCR under different conditions was proposed based on in situ experiments and physicochemical analyses.


Asunto(s)
Gases , Emisiones de Vehículos , Oxidación-Reducción , Catálisis , Amoníaco/química
11.
Bioorg Chem ; 131: 106324, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36563414

RESUMEN

Chemical investigation of an alcohol extract from the twigs and leaves of Illicium henryi Diels resulted in the isolation of two new acorane-related seco-sesquiterpenes (1 and 3), two new acorane-related seco-norsesquiterpenes (2 and 4), one new 2-epi-cedrane sesquiterpene (5), eight new acorane-type sesquiterpenes (6-13), and a known major constituent of acorenone B (14). Their structures were established by interpreting extensive spectroscopic data, including HRESIMS, NMR (1H and 13C NMR, 1H-1H COSY, HSQC, and HMBC), and NOE difference spectra analysis. The absolute configurations of 1, 2, 4-7, 9, 10, and 14 were determined by X-ray crystallography, while chemical transformation methods were performed with compound 14 as the starting material to elegantly solve the absolute configuration issue of compounds 8 and 11-13. Notably, 1 and 2 are seco-sesquiterpenes that are related to acorane and possess an unusual ketal-linked hemiacetal in a 6,8-dioxabicyclo[3.2.1]octan-7-ol scaffold ring system. Plausible biosynthetic pathways for compounds 1-14, which were derived from the acorane skeleton, were proposed. All the isolated compounds (1-14) were evaluated for their antiviral and cytotoxic activities.


Asunto(s)
Antivirales , Illicium , Sesquiterpenos , Antivirales/química , Antivirales/farmacología , Illicium/química , Espectroscopía de Resonancia Magnética , Estructura Molecular , Hojas de la Planta/química , Sesquiterpenos/química , Sesquiterpenos/farmacología
12.
Xenobiotica ; 53(12): 634-643, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38053346

RESUMEN

C. officinalis Kuan is the dry root of Cyathula officinalis Kuan. Clinically, it is used for fall and flutter injury, rheumatism and arthralgia. Phytoecdysteroids have significant anti-inflammatory effects, and the phytoecdysteroids present in C. officinalis Kuan exhibit potential for treating rheumatoid arthritis.This study first developed a selective, accurate and efficient LC-MS/MS method for 12-day pharmacokinetic studies regarding the simultaneous determination of cyasterone, 25-epi-28-epi-cyasterone, precyasterone and capitasterone from C. officinalis Kuan phytoecdysteroids extract in normal and adjuvant arthritis rats.An Agilent Eclipse Plus C18 RRHD column (1.8 µm, 50mm × 2.1 mm) with a gradient mobile phase consisting of water (A) and acetonitrile (B) was used for analysis. The mass analysis was performed in an Agilent 6430 QQQ-MS mass spectrometer with positive mode multiple reaction monitoring (MRM).The results indicated that the AUC0-t and AUC0-∞ values of the four phytoecdysteroids in adjuvant arthritis rats were different from those in normal rats on the first day, which could provide a helpful reference for pharmacological and toxicological studies, as well as clinical applications of C. officinalis Kuan in the treatment of rheumatoid arthritis.


1. C. officinalis Kuan is the dry root of Cyathula officinalis Kuan which has been used for the treatment of flapping injury, rheumatism arthralgia, foot flaccidity, and tendon contracture thousands of years in China, and has been officially included in the Chinese Pharmacopoeia.2. A highly accurate, stable, and sensitive ultra-performance liquid chromatography with tandem mass spectrometry (UHPLC-MS/MS) method was first established and validated for simultaneously determination four phytoecdysteroids: cyasterone, 25-epi-28-epi-cyasterone, precyasterone and capitasterone in normal and adjuvant arthritis rats plasma samples 12 days of continuous gavage of C. officinalis Kuan phytoecdysteroids extract.3. The phytoecdysteroids is the important component of C. officinalis Kuan, which is difficult to separated. And there is no report for the pharmacokinetic study of phytoecdysteroids from C. officinalis Kuan. And the method provides a good reference for the follow-up studies clinical medication of the phytoecdysteroids from C. officinalis Kuan.


Asunto(s)
Artritis Experimental , Artritis Reumatoide , Medicamentos Herbarios Chinos , Ratas , Animales , Cromatografía Liquida/métodos , Espectrometría de Masas en Tándem/métodos , Cromatografía Líquida de Alta Presión/métodos , Cromatografía Líquida con Espectrometría de Masas , Artritis Experimental/tratamiento farmacológico , Administración Oral , Artritis Reumatoide/tratamiento farmacológico , Reproducibilidad de los Resultados
13.
J Asian Nat Prod Res ; 25(7): 617-626, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36300525

RESUMEN

One new taraxastane-type triterpenoid, three new grayanane-type diterpenoids (2 - 4), and 12 known compounds (5 - 16) were isolated from the leaves of Craiobiodendron yunnanens W. W. Smith. The structures of these compounds were elucidated on the basis of their spectroscopic data and chemical evidence. Compounds 1 and 8 exhibited partly anti-inflammatory activity based on the inhibition of NF-κB activity in SW480 cells at 10 µM with inhibition ratios of 60.53 and 59.20%, respectively. Compounds 10 and 13 showed excellent cytotoxicity against human leukemia cell (MV4-11) at 10 µM with inhibition ratios of 43.02 and 49.11%, respectively.


Asunto(s)
Diterpenos , Ericaceae , Humanos , Terpenos/farmacología , Estructura Molecular , Ericaceae/química , Hojas de la Planta/química , Diterpenos/farmacología , Diterpenos/química
14.
Molecules ; 28(9)2023 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-37175275

RESUMEN

Recently, single-atom catalysts (SACs) have attracted wide attention in the field of environmental engineering. Compared with their nanoparticle counterparts, SACs possess high atomic efficiency, unique catalytic activity, and selectivity. This review summarizes recent studies on the environmental remediation applications of SACs in (1) gaseous: volatile organic compounds (VOCs) treatment, NOx reduction, CO2 reduction, and CO oxidation; (2) aqueous: Fenton-like advanced oxidation processes (AOPs), hydrodehalogenation, and nitrate/nitrite reduction. We present the treatment activities and reaction mechanisms of various SACs and propose challenges and future opportunities. We believe that this review will provide constructive inspiration and direction for future SAC research in environmental engineering.

15.
Zhongguo Zhong Yao Za Zhi ; 48(4): 978-984, 2023 Feb.
Artículo en Zh | MEDLINE | ID: mdl-36872268

RESUMEN

The present study investigated the chemical constituents from the leaves of Craibiodendron yunnanense. The compounds were isolated and purified from the leaves of C. yunnanense by a combination of various chromatographic techniques including column chromatography over polyamide, silica gel, Sephadex LH-20, and reversed-phase HPLC. Their structures were identified by extensive spectroscopic analyses including MS and NMR data. As a result, 10 compounds, including melionoside F(1), meliosmaionol D(2), naringenin(3), quercetin-3-O-α-L-arabinopyranoside(4), epicatechin(5), quercetin-3'-glucoside(6), corbulain Ib(7), loliolide(8), asiatic acid(9), and ursolic acid(10), were isolated. Compounds 1 and 2 were two new compounds, and compound 7 was isolated from this genus for the first time. All compounds showed no significant cytotoxic activity by MTT assay.


Asunto(s)
Catequina , Ericaceae , Quercetina , Hojas de la Planta , Cromatografía Líquida de Alta Presión
16.
BMC Cancer ; 22(1): 1238, 2022 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-36451138

RESUMEN

BACKGROUND: There is still uncertainty on whether ionizing radiation from CT scans can increase the risks of cancer. This study aimed to identify the association of cumulative ionizing radiation from CT scans with pertaining cancer risks in adults. METHODS: Five databases were searched from their inception to November 15, 2020. Observational studies reporting cancer risks from CT scans in adults were included. The main outcome included quantified cancer risks as cancer case numbers in exposed/unexposed adult participants with unified converted measures to odds ratio (OR) for relative risk, hazard ratio. Global background radiation (2.4 mSv per year) was used as control for lifetime attribution risk (LAR), with the same period from incubation after exposure until survival to 100 years. RESULTS: 25 studies were included with a sum of 111,649,943 participants (mean age: 45.37 years, 83.4% women), comprising 2,049,943 actual participants from 6 studies with an average follow-up period as 30.1 years (range, 5 to 80 years); 109,600,000 participants from 19 studies using LAR. The cancer risks for adults following CT scans were inordinately increased (LAR adults, OR, 10.00 [95% CI, 5.87 to 17.05]; actual adults, OR, 1.17 [95%CI, 0.89 to 1.55]; combined, OR, 5.89 [95%CI, 3.46 to 10.35]). Moreover, cancer risks elevated with increase of radiation dose (OR, 33.31 [95% CI, 21.33 to 52.02]), and multiple CT scan sites (OR, 14.08 [95% CI, 6.60 to 30.05]). The risk of solid malignancy was higher than leukemia. Notably, there were no significant differences for age, gender, country, continent, study quality and studying time phrases. CONCLUSIONS: Based on 111.6 million adult participants from 3 continents (Asia, Europe and America), this meta-analysis identifies an inordinately increase in cancer risks from CT scans for adults. Moreover, the cancer risks were positively correlated with radiation dose and CT sites. The meta-analysis highlights the awareness of potential cancer risks of CT scans as well as more reasonable methodology to quantify cancer risks in terms of life expectancy as 100 years for LAR. PROSPERO TRIAL REGISTRATION NUMBER: CRD42019133487.


Asunto(s)
Leucemia , Neoplasias , Adulto , Femenino , Humanos , Persona de Mediana Edad , Masculino , Tomografía Computarizada por Rayos X/efectos adversos , Neoplasias/diagnóstico por imagen , Neoplasias/epidemiología , Neoplasias/etiología , Radiación Ionizante , Oportunidad Relativa
17.
J Asian Nat Prod Res ; 24(10): 925-934, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35899696

RESUMEN

Four new germacrane-type sesquiterpenoids (1-4) and two new guaiane-type sesquiterpenoids (5-6) were isolated from the fruits of Xanthium italicum Moretti. The structures of the new compounds were elucidated on the basis of spectroscopic analysis and X-ray diffraction experiment. Compounds 1, 2 and 6 showed the anti-inflammatory effects against the activation of NF-κB induced by lipopolysaccharide (LPS) with IC50 values of 20.12, 22.89 and 68.66 µM, respectively.


Asunto(s)
Sesquiterpenos , Xanthium , Xanthium/química , Frutas/química , Estructura Molecular , Sesquiterpenos/farmacología , Sesquiterpenos/química , Lipopolisacáridos/farmacología
18.
J Asian Nat Prod Res ; 24(6): 518-527, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34212783

RESUMEN

A pair of new lignans [(+)- 1 and (-)- 1] and three new compounds (2-4), together with a known compound 5, were isolated from the fruits of Xanthium italicum Moretti. The structures of these compounds were determined on the basis of spectroscopic analysis, particularly HR-ESI-MS and 1 D and 2 D NMR. Compounds 2 and 3 showed antinociceptive effects in an acetic acid-induced writhing test in mice with the writhe inhibition rates of 80.50% and 67.89% at the dose of 20 mg/kg, respectively.


Asunto(s)
Diterpenos , Lignanos , Xanthium , Animales , Frutas/química , Glicósidos/química , Lignanos/análisis , Lignanos/farmacología , Ratones , Estructura Molecular , Xanthium/química
19.
J Asian Nat Prod Res ; 24(5): 445-456, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35038936

RESUMEN

Four minor undescribed terpenoids, including a monoterpenoid (1) and three triterpenoids (3, 6 and 7), together with 26 known terpenoids were isolated from the stems and twigs of Rhododendron Ovatum. Their structures were identified by extensive spectroscopic analyses and electronic circular dichroism (ECD) techniques. Compound 10 showed excellent cytotoxicity against human colon cancer cell (HCT-116) with IC50 value of 2.56 µM. Compounds 9 and 19 exhibited partly inhibitory effects on nitric oxide production stimulated by lipopolysaccharide-induced neuroinflammation in microglia cells at 10 µM with inhibition ratios of 39.70% and 28.08%, respectively.


Asunto(s)
Rhododendron , Triterpenos , Lipopolisacáridos/farmacología , Estructura Molecular , Óxido Nítrico , Rhododendron/química , Terpenos/química , Terpenos/farmacología , Triterpenos/química
20.
J Environ Sci (China) ; 111: 175-184, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34949347

RESUMEN

Herein, a series of niobium oxide supported cerium nanotubes (CeNTs) catalysts with different loading amount of Nb2O5 (0-10 wt.%) were prepared and used for selective catalytic reduction of NOx with NH3 (NH3-SCR) in the presence of CH2Cl2. Commercial V2O5-WO3-TiO2 catalyst was also prepared for comparison. The physcial properties and chemical properties of the Nb2O5 loaded cerium nanotubes catalysts were investigated by X-ray diffractometer, Transmission electron microscope, Brunauer-Emmett-Teller specific surface area, H2-temperature programmed reduction, NH3-temperature programmed desorption and X-ray photoelectron spectroscopy. The experiment results showed that the loading amount of Nb2O5 had a significant effect on the catalytic performance of the catalysts. 10 wt.% Nb-CeNTs catalyst presented the best NH3-SCR performance and degradation efficiency of CH2Cl2 among the prepared catalysts, due to its superior redox capability, abundant surface oxygen species and acid sites, the interaction between Nb and Ce, higher ratio of Nb4+/(Nb5++ Nb4+) and Ce3+/(Ce3+ + Ce4+), as well as the special tubular structure of cerium nanotube. This study may provide a practical approach for the design and synthesis of SCR catalysts for the simultaneously removal NOx and chlorinated volatile organic compounds (CVOCs) emitted from the stationary industrial sources.


Asunto(s)
Cerio , Nanotubos , Amoníaco , Catálisis , Cloruro de Metileno , Niobio , Oxidación-Reducción , Titanio
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